app/vlogscli: add interactive command-line tool for querying VictoriaLogs

Makefile

@@ -27,6 +27,7 @@ include package/release/Makefile
 all: \
 	victoria-metrics-prod \
 	victoria-logs-prod \
+	vlogscli-prod \
 	vmagent-prod \
 	vmalert-prod \
 	vmalert-tool-prod \
@@ -51,6 +52,7 @@ publish: \
 package: \
 	package-victoria-metrics \
 	package-victoria-logs \
+	package-vlogscli \
 	package-vmagent \
 	package-vmalert \
 	package-vmalert-tool \
@@ -320,6 +322,63 @@ release-victoria-logs-windows-goarch: victoria-logs-windows-$(GOARCH)-prod
 	cd bin && rm -rf \
 		victoria-logs-windows-$(GOARCH)-prod.exe
 
+release-vlogscli:
+	$(MAKE_PARALLEL) release-vlogscli-linux-386 \
+		release-vlogscli-linux-amd64 \
+		release-vlogscli-linux-arm \
+		release-vlogscli-linux-arm64 \
+		release-vlogscli-darwin-amd64 \
+		release-vlogscli-darwin-arm64 \
+		release-vlogscli-freebsd-amd64 \
+		release-vlogscli-openbsd-amd64 \
+		release-vlogscli-windows-amd64
+
+release-vlogscli-linux-386:
+	GOOS=linux GOARCH=386 $(MAKE) release-vlogscli-goos-goarch
+
+release-vlogscli-linux-amd64:
+	GOOS=linux GOARCH=amd64 $(MAKE) release-vlogscli-goos-goarch
+
+release-vlogscli-linux-arm:
+	GOOS=linux GOARCH=arm $(MAKE) release-vlogscli-goos-goarch
+
+release-vlogscli-linux-arm64:
+	GOOS=linux GOARCH=arm64 $(MAKE) release-vlogscli-goos-goarch
+
+release-vlogscli-darwin-amd64:
+	GOOS=darwin GOARCH=amd64 $(MAKE) release-vlogscli-goos-goarch
+
+release-vlogscli-darwin-arm64:
+	GOOS=darwin GOARCH=arm64 $(MAKE) release-vlogscli-goos-goarch
+
+release-vlogscli-freebsd-amd64:
+	GOOS=freebsd GOARCH=amd64 $(MAKE) release-vlogscli-goos-goarch
+
+release-vlogscli-openbsd-amd64:
+	GOOS=openbsd GOARCH=amd64 $(MAKE) release-vlogscli-goos-goarch
+
+release-vlogscli-windows-amd64:
+	GOARCH=amd64 $(MAKE) release-vlogscli-windows-goarch
+
+release-vlogscli-goos-goarch: vlogscli-$(GOOS)-$(GOARCH)-prod
+	cd bin && \
+		tar $(TAR_OWNERSHIP) --transform="flags=r;s|-$(GOOS)-$(GOARCH)||" -czf vlogscli-$(GOOS)-$(GOARCH)-$(PKG_TAG).tar.gz \
+			vlogscli-$(GOOS)-$(GOARCH)-prod \
+		&& sha256sum vlogscli-$(GOOS)-$(GOARCH)-$(PKG_TAG).tar.gz \
+			vlogscli-$(GOOS)-$(GOARCH)-prod \
+			| sed s/-$(GOOS)-$(GOARCH)-prod/-prod/ > vlogscli-$(GOOS)-$(GOARCH)-$(PKG_TAG)_checksums.txt
+	cd bin && rm -rf vlogscli-$(GOOS)-$(GOARCH)-prod
+
+release-vlogscli-windows-goarch: vlogscli-windows-$(GOARCH)-prod
+	cd bin && \
+		zip vlogscli-windows-$(GOARCH)-$(PKG_TAG).zip \
+			vlogscli-windows-$(GOARCH)-prod.exe \
+		&& sha256sum vlogscli-windows-$(GOARCH)-$(PKG_TAG).zip \
+			vlogscli-windows-$(GOARCH)-prod.exe \
+			> vlogscli-windows-$(GOARCH)-$(PKG_TAG)_checksums.txt
+	cd bin && rm -rf \
+		vlogscli-windows-$(GOARCH)-prod.exe
+
 release-vmutils: \
 	release-vmutils-linux-386 \
 	release-vmutils-linux-amd64 \

app/vlogscli/Makefile

@@ -0,0 +1,109 @@
+# All these commands must run from repository root.
+
+vlogscli:
+	APP_NAME=vlogscli $(MAKE) app-local
+
+vlogscli-race:
+	APP_NAME=vlogscli RACE=-race $(MAKE) app-local
+
+vlogscli-prod:
+	APP_NAME=vlogscli $(MAKE) app-via-docker
+
+vlogscli-pure-prod:
+	APP_NAME=vlogscli $(MAKE) app-via-docker-pure
+
+vlogscli-linux-amd64-prod:
+	APP_NAME=vlogscli $(MAKE) app-via-docker-linux-amd64
+
+vlogscli-linux-arm-prod:
+	APP_NAME=vlogscli $(MAKE) app-via-docker-linux-arm
+
+vlogscli-linux-arm64-prod:
+	APP_NAME=vlogscli $(MAKE) app-via-docker-linux-arm64
+
+vlogscli-linux-ppc64le-prod:
+	APP_NAME=vlogscli $(MAKE) app-via-docker-linux-ppc64le
+
+vlogscli-linux-386-prod:
+	APP_NAME=vlogscli $(MAKE) app-via-docker-linux-386
+
+vlogscli-darwin-amd64-prod:
+	APP_NAME=vlogscli $(MAKE) app-via-docker-darwin-amd64
+
+vlogscli-darwin-arm64-prod:
+	APP_NAME=vlogscli $(MAKE) app-via-docker-darwin-arm64
+
+vlogscli-freebsd-amd64-prod:
+	APP_NAME=vlogscli $(MAKE) app-via-docker-freebsd-amd64
+
+vlogscli-openbsd-amd64-prod:
+	APP_NAME=vlogscli $(MAKE) app-via-docker-openbsd-amd64
+
+vlogscli-windows-amd64-prod:
+	APP_NAME=vlogscli $(MAKE) app-via-docker-windows-amd64
+
+package-vlogscli:
+	APP_NAME=vlogscli $(MAKE) package-via-docker
+
+package-vlogscli-pure:
+	APP_NAME=vlogscli $(MAKE) package-via-docker-pure
+
+package-vlogscli-amd64:
+	APP_NAME=vlogscli $(MAKE) package-via-docker-amd64
+
+package-vlogscli-arm:
+	APP_NAME=vlogscli $(MAKE) package-via-docker-arm
+
+package-vlogscli-arm64:
+	APP_NAME=vlogscli $(MAKE) package-via-docker-arm64
+
+package-vlogscli-ppc64le:
+	APP_NAME=vlogscli $(MAKE) package-via-docker-ppc64le
+
+package-vlogscli-386:
+	APP_NAME=vlogscli $(MAKE) package-via-docker-386
+
+publish-vlogscli:
+	APP_NAME=vlogscli $(MAKE) publish-via-docker
+
+vlogscli-linux-amd64:
+	APP_NAME=vlogscli CGO_ENABLED=1 GOOS=linux GOARCH=amd64 $(MAKE) app-local-goos-goarch
+
+vlogscli-linux-arm:
+	APP_NAME=vlogscli CGO_ENABLED=0 GOOS=linux GOARCH=arm $(MAKE) app-local-goos-goarch
+
+vlogscli-linux-arm64:
+	APP_NAME=vlogscli CGO_ENABLED=0 GOOS=linux GOARCH=arm64 $(MAKE) app-local-goos-goarch
+
+vlogscli-linux-ppc64le:
+	APP_NAME=vlogscli CGO_ENABLED=0 GOOS=linux GOARCH=ppc64le $(MAKE) app-local-goos-goarch
+
+vlogscli-linux-s390x:
+	APP_NAME=vlogscli CGO_ENABLED=0 GOOS=linux GOARCH=s390x $(MAKE) app-local-goos-goarch
+
+vlogscli-linux-loong64:
+	APP_NAME=vlogscli CGO_ENABLED=0 GOOS=linux GOARCH=loong64 $(MAKE) app-local-goos-goarch
+
+vlogscli-linux-386:
+	APP_NAME=vlogscli CGO_ENABLED=0 GOOS=linux GOARCH=386 $(MAKE) app-local-goos-goarch
+
+vlogscli-darwin-amd64:
+	APP_NAME=vlogscli CGO_ENABLED=0 GOOS=darwin GOARCH=amd64 $(MAKE) app-local-goos-goarch
+
+vlogscli-darwin-arm64:
+	APP_NAME=vlogscli CGO_ENABLED=0 GOOS=darwin GOARCH=arm64 $(MAKE) app-local-goos-goarch
+
+vlogscli-freebsd-amd64:
+	APP_NAME=vlogscli CGO_ENABLED=0 GOOS=freebsd GOARCH=amd64 $(MAKE) app-local-goos-goarch
+
+vlogscli-openbsd-amd64:
+	APP_NAME=vlogscli CGO_ENABLED=0 GOOS=openbsd GOARCH=amd64 $(MAKE) app-local-goos-goarch
+
+vlogscli-windows-amd64:
+	GOARCH=amd64 APP_NAME=vlogscli $(MAKE) app-local-windows-goarch
+
+vlogscli-pure:
+	APP_NAME=vlogscli $(MAKE) app-local-pure
+
+run-vlogscli:
+	APP_NAME=vlogscli $(MAKE) run-via-docker

app/vlogscli/README.md

@@ -0,0 +1,5 @@
+# vlogscli
+
+Command-line utility for querying [VictoriaLogs](https://docs.victoriametrics.com/victorialogs/).
+
+See [these docs](https://docs.victoriametrics.com/victorialogs/querying/vlogscli/).

app/vlogscli/deployment/Dockerfile

@@ -0,0 +1,6 @@
+ARG base_image=non-existing
+FROM $base_image
+
+ENTRYPOINT ["/vlogscli-prod"]
+ARG src_binary=non-existing
+COPY $src_binary ./vlogscli-prod

app/vlogscli/json_prettifier.go

@@ -0,0 +1,73 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"sync"
+)
+
+type jsonPrettifier struct {
+	rOriginal io.ReadCloser
+
+	d *json.Decoder
+
+	pr *io.PipeReader
+	pw *io.PipeWriter
+
+	wg sync.WaitGroup
+}
+
+func newJSONPrettifier(r io.ReadCloser) *jsonPrettifier {
+	d := json.NewDecoder(r)
+	pr, pw := io.Pipe()
+
+	jp := &jsonPrettifier{
+		rOriginal: r,
+		d:         d,
+		pr:        pr,
+		pw:        pw,
+	}
+
+	jp.wg.Add(1)
+	go func() {
+		defer jp.wg.Done()
+		err := jp.prettifyJSONLines()
+		jp.closePipesWithError(err)
+	}()
+
+	return jp
+}
+
+func (jp *jsonPrettifier) closePipesWithError(err error) {
+	_ = jp.pr.CloseWithError(err)
+	_ = jp.pw.CloseWithError(err)
+}
+
+func (jp *jsonPrettifier) prettifyJSONLines() error {
+	for jp.d.More() {
+		var v any
+		if err := jp.d.Decode(&v); err != nil {
+			return err
+		}
+		line, err := json.MarshalIndent(v, "", "  ")
+		if err != nil {
+			panic(fmt.Errorf("BUG: cannot marshal %v to JSON: %w", v, err))
+		}
+		if _, err := fmt.Fprintf(jp.pw, "%s\n", line); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (jp *jsonPrettifier) Close() error {
+	jp.closePipesWithError(io.ErrUnexpectedEOF)
+	err := jp.rOriginal.Close()
+	jp.wg.Wait()
+	return err
+}
+
+func (jp *jsonPrettifier) Read(p []byte) (int, error) {
+	return jp.pr.Read(p)
+}

app/vlogscli/less_wrapper.go

@@ -0,0 +1,116 @@
+package main
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"os/exec"
+	"os/signal"
+	"sync"
+	"syscall"
+
+	"github.com/mattn/go-isatty"
+)
+
+func isTerminal() bool {
+	return isatty.IsTerminal(os.Stdout.Fd()) && isatty.IsTerminal(os.Stderr.Fd())
+}
+
+func readWithLess(r io.Reader) error {
+	if !isTerminal() {
+		// Just write everything to stdout if no terminal is available.
+		_, err := io.Copy(os.Stdout, r)
+		if err != nil && !isErrPipe(err) {
+			return fmt.Errorf("error when forwarding data to stdout: %w", err)
+		}
+		if err := os.Stdout.Sync(); err != nil {
+			return fmt.Errorf("cannot sync data to stdout: %w", err)
+		}
+		return nil
+	}
+
+	pr, pw, err := os.Pipe()
+	if err != nil {
+		return fmt.Errorf("cannot create pipe: %w", err)
+	}
+	defer func() {
+		_ = pr.Close()
+		_ = pw.Close()
+	}()
+
+	// Ignore Ctrl+C in the current process, so 'less' could handle it properly
+	cancel := ignoreSignals(os.Interrupt)
+	defer cancel()
+
+	// Start 'less' process
+	path, err := exec.LookPath("less")
+	if err != nil {
+		return fmt.Errorf("cannot find 'less' command: %w", err)
+	}
+	p, err := os.StartProcess(path, []string{"less", "-F"}, &os.ProcAttr{
+		Env:   append(os.Environ(), "LESSCHARSET=utf-8"),
+		Files: []*os.File{pr, os.Stdout, os.Stderr},
+	})
+	if err != nil {
+		return fmt.Errorf("cannot start 'less' process: %w", err)
+	}
+
+	// Close pr after 'less' finishes in a parallel goroutine
+	// in order to unblock forwarding data to stopped 'less' below.
+	waitch := make(chan *os.ProcessState)
+	go func() {
+		// Wait for 'less' process to finish.
+		ps, err := p.Wait()
+		if err != nil {
+			fatalf("unexpected error when waiting for 'less' process: %w", err)
+		}
+		_ = pr.Close()
+		waitch <- ps
+	}()
+
+	// Forward data from r to 'less'
+	_, err = io.Copy(pw, r)
+	_ = pw.Sync()
+	_ = pw.Close()
+
+	// Wait until 'less' finished
+	ps := <-waitch
+
+	// Verify 'less' status.
+	if !ps.Success() {
+		return fmt.Errorf("'less' finished with unexpected code %d", ps.ExitCode())
+	}
+
+	if err != nil && !isErrPipe(err) {
+		return fmt.Errorf("error when forwarding data to 'less': %w", err)
+	}
+
+	return nil
+}
+
+func isErrPipe(err error) bool {
+	return errors.Is(err, syscall.EPIPE) || errors.Is(err, io.ErrClosedPipe)
+}
+
+func ignoreSignals(sigs ...os.Signal) func() {
+	ch := make(chan os.Signal, 1)
+	signal.Notify(ch, sigs...)
+
+	var wg sync.WaitGroup
+	wg.Add(1)
+	go func() {
+		defer wg.Done()
+		for {
+			_, ok := <-ch
+			if !ok {
+				return
+			}
+		}
+	}()
+	return func() {
+		signal.Stop(ch)
+		close(ch)
+		wg.Wait()
+	}
+}

app/vlogscli/main.go

@@ -0,0 +1,301 @@
+package main
+
+import (
+	"context"
+	"errors"
+	"flag"
+	"fmt"
+	"io"
+	"io/fs"
+	"net/http"
+	"net/url"
+	"os"
+	"os/signal"
+	"strconv"
+	"strings"
+	"syscall"
+	"time"
+
+	"github.com/ergochat/readline"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/buildinfo"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/envflag"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/flagutil"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logstorage"
+)
+
+var (
+	datasourceURL = flag.String("datasource.url", "http://localhost:9428/select/logsql/query", "URL for querying VictoriaLogs; "+
+		"see https://docs.victoriametrics.com/victorialogs/querying/#querying-logs")
+	historyFile = flag.String("historyFile", "vlogscli-history", "Path to file with command history")
+	header      = flagutil.NewArrayString("header", "Optional header to pass in request -datasource.url in the form 'HeaderName: value'")
+)
+
+const (
+	firstLinePrompt = ";> "
+	nextLinePrompt  = ""
+)
+
+func main() {
+	// Write flags and help message to stdout, since it is easier to grep or pipe.
+	flag.CommandLine.SetOutput(os.Stdout)
+	flag.Usage = usage
+	envflag.Parse()
+	buildinfo.Init()
+	logger.InitNoLogFlags()
+
+	hes, err := parseHeaders(*header)
+	if err != nil {
+		fatalf("cannot parse -header command-line flag: %s", err)
+	}
+	headers = hes
+
+	isEmptyLine := true
+	cfg := &readline.Config{
+		Prompt:                 firstLinePrompt,
+		DisableAutoSaveHistory: true,
+		Listener: func(line []rune, pos int, _ rune) ([]rune, int, bool) {
+			isEmptyLine = len(line) == 0
+			return line, pos, false
+		},
+	}
+	rl, err := readline.NewFromConfig(cfg)
+	if err != nil {
+		fatalf("cannot initialize readline: %s", err)
+	}
+
+	fmt.Fprintf(rl, "sending queries to %s\n", *datasourceURL)
+
+	runReadlineLoop(rl, &isEmptyLine)
+
+	if err := rl.Close(); err != nil {
+		fatalf("cannot close readline: %s", err)
+	}
+
+}
+
+func runReadlineLoop(rl *readline.Instance, isEmptyLine *bool) {
+	historyLines, err := loadFromHistory(*historyFile)
+	if err != nil {
+		fatalf("cannot load query history: %s", err)
+	}
+	for _, line := range historyLines {
+		if err := rl.SaveToHistory(line); err != nil {
+			fatalf("cannot initialize query history: %s", err)
+		}
+	}
+
+	s := ""
+	for {
+		line, err := rl.ReadLine()
+		if err != nil {
+			switch err {
+			case io.EOF:
+				if s != "" {
+					// This is non-interactive query execution.
+					if err := executeQuery(context.Background(), rl, s); err != nil {
+						fmt.Fprintf(rl, "%s\n", err)
+					}
+				}
+				return
+			case readline.ErrInterrupt:
+				if s == "" && *isEmptyLine {
+					fmt.Fprintf(rl, "interrupted\n")
+					os.Exit(128 + int(syscall.SIGINT))
+				}
+				// Default value for Ctrl+C - clear the prompt
+				s = ""
+				rl.SetPrompt(firstLinePrompt)
+				continue
+			default:
+				fatalf("unexpected error in readline: %s", err)
+			}
+		}
+
+		s += line
+		if isQuitCommand(s) {
+			fmt.Fprintf(rl, "bye!\n")
+			return
+		}
+		if s == "" {
+			// Skip empty lines
+			continue
+		}
+		if line != "" && !strings.HasSuffix(line, ";") {
+			// Assume the query is incomplete and allow the user finishing the query on the next line
+			s += "\n"
+			rl.SetPrompt(nextLinePrompt)
+			continue
+		}
+
+		// Execute the query
+		ctx, cancel := signal.NotifyContext(context.Background(), os.Interrupt)
+		err = executeQuery(ctx, rl, s)
+		cancel()
+
+		if err != nil {
+			if errors.Is(err, context.Canceled) {
+				fmt.Fprintf(rl, "\n")
+			} else {
+				fmt.Fprintf(rl, "%s\n", err)
+			}
+			// Save queries in the history even if they weren't finished successfully
+		}
+
+		s = strings.TrimSpace(s)
+		if len(historyLines) == 0 || historyLines[len(historyLines)-1] != s {
+			historyLines = append(historyLines, s)
+			if len(historyLines) > 500 {
+				historyLines = historyLines[len(historyLines)-500:]
+			}
+			if err := saveToHistory(*historyFile, historyLines); err != nil {
+				fatalf("cannot save query history: %s", err)
+			}
+		}
+		if err := rl.SaveToHistory(s); err != nil {
+			fatalf("cannot update query history: %s", err)
+		}
+		s = ""
+		rl.SetPrompt(firstLinePrompt)
+	}
+}
+
+func loadFromHistory(filePath string) ([]string, error) {
+	data, err := os.ReadFile(filePath)
+	if err != nil {
+		if errors.Is(err, fs.ErrNotExist) {
+			return nil, nil
+		}
+		return nil, err
+	}
+	linesQuoted := strings.Split(string(data), "\n")
+	lines := make([]string, 0, len(linesQuoted))
+	i := 0
+	for _, lineQuoted := range linesQuoted {
+		i++
+		if lineQuoted == "" {
+			continue
+		}
+		line, err := strconv.Unquote(lineQuoted)
+		if err != nil {
+			return nil, fmt.Errorf("cannot parse line #%d at %s: %w; line: [%s]", i, filePath, err, line)
+		}
+		lines = append(lines, line)
+	}
+	return lines, nil
+}
+
+func saveToHistory(filePath string, lines []string) error {
+	linesQuoted := make([]string, len(lines))
+	for i, line := range lines {
+		lineQuoted := strconv.Quote(line)
+		linesQuoted[i] = lineQuoted
+	}
+	data := strings.Join(linesQuoted, "\n")
+	return os.WriteFile(filePath, []byte(data), 0600)
+}
+
+func isQuitCommand(s string) bool {
+	switch s {
+	case "q", "quit", "exit":
+		return true
+	default:
+		return false
+	}
+}
+
+func executeQuery(ctx context.Context, output io.Writer, s string) error {
+	// Parse the query and convert it to canonical view.
+	s = strings.TrimSuffix(s, ";")
+	q, err := logstorage.ParseQuery(s)
+	if err != nil {
+		return fmt.Errorf("cannot parse query: %w", err)
+	}
+	qStr := q.String()
+	fmt.Fprintf(output, "executing [%s]...", qStr)
+
+	// Prepare HTTP request for VictoriaLogs
+	args := make(url.Values)
+	args.Set("query", qStr)
+	data := strings.NewReader(args.Encode())
+
+	req, err := http.NewRequestWithContext(ctx, "POST", *datasourceURL, data)
+	if err != nil {
+		panic(fmt.Errorf("BUG: cannot prepare request to server: %w", err))
+	}
+	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
+	for _, h := range headers {
+		req.Header.Set(h.Name, h.Value)
+	}
+
+	// Execute HTTP request at VictoriaLogs
+	startTime := time.Now()
+	resp, err := httpClient.Do(req)
+	queryDuration := time.Since(startTime)
+	fmt.Fprintf(output, "; duration: %.3fs\n", queryDuration.Seconds())
+	if err != nil {
+		return fmt.Errorf("cannot execute query: %w", err)
+	}
+	defer func() {
+		_ = resp.Body.Close()
+	}()
+
+	if resp.StatusCode != http.StatusOK {
+		body, err := io.ReadAll(resp.Body)
+		if err != nil {
+			body = []byte(fmt.Sprintf("cannot read response body: %s", err))
+		}
+		return fmt.Errorf("unexpected status code: %d; response body:\n%s", resp.StatusCode, body)
+	}
+
+	// Prettify the response and stream it to 'less'.
+	jp := newJSONPrettifier(resp.Body)
+	defer func() {
+		_ = jp.Close()
+	}()
+
+	if err := readWithLess(jp); err != nil {
+		return fmt.Errorf("error when reading query response: %w", err)
+	}
+
+	return nil
+}
+
+var httpClient = &http.Client{}
+
+var headers []headerEntry
+
+type headerEntry struct {
+	Name  string
+	Value string
+}
+
+func parseHeaders(a []string) ([]headerEntry, error) {
+	hes := make([]headerEntry, len(a))
+	for i, s := range a {
+		a := strings.SplitN(s, ":", 2)
+		if len(a) != 2 {
+			return nil, fmt.Errorf("cannot parse header=%q; it must contain at least one ':'; for example, 'Cookie: foo'", s)
+		}
+		hes[i] = headerEntry{
+			Name:  strings.TrimSpace(a[0]),
+			Value: strings.TrimSpace(a[1]),
+		}
+	}
+	return hes, nil
+}
+
+func fatalf(format string, args ...any) {
+	fmt.Fprintf(os.Stderr, format+"\n", args...)
+	os.Exit(1)
+}
+
+func usage() {
+	const s = `
+vlogscli is a command-line tool for querying VictoriaLogs.
+
+See the docs at https://docs.victoriametrics.com/victorialogs/querying/vlogscli/
+`
+	flagutil.Usage(s)
+}

app/vlogscli/multiarch/Dockerfile

@@ -0,0 +1,11 @@
+# See https://medium.com/on-docker/use-multi-stage-builds-to-inject-ca-certs-ad1e8f01de1b
+ARG certs_image=non-existing
+ARG root_image=non-existing
+FROM $certs_image AS certs
+RUN apk update && apk upgrade && apk --update --no-cache add ca-certificates
+
+FROM $root_image
+COPY --from=certs /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/ca-certificates.crt
+ENTRYPOINT ["/vlogscli-prod"]
+ARG TARGETARCH
+COPY vlogscli-linux-${TARGETARCH}-prod ./vlogscli-prod

docs/VictoriaLogs/CHANGELOG.md

@@ -15,6 +15,8 @@ according to [these docs](https://docs.victoriametrics.com/victorialogs/quicksta
 
 ## tip
 
+* FEATURE: add interactive command-line tool for querying VictoriaLogs - [`vlogscli`](https://docs.victoriametrics.com/victorialogs/querying/vlogscli/).
+
 ## [v0.32.1](https://github.com/VictoriaMetrics/VictoriaMetrics/releases/tag/v0.32.1-victorialogs)
 
 Released at 2024-09-30

docs/VictoriaLogs/README.md

@@ -3,25 +3,27 @@ from [VictoriaMetrics](https://github.com/VictoriaMetrics/VictoriaMetrics/).
 
 VictoriaLogs provides the following features:
 
-- VictoriaLogs can accept logs from popular log collectors. See [these docs](https://docs.victoriametrics.com/victorialogs/data-ingestion/).
-- VictoriaLogs is much easier to set up and operate compared to Elasticsearch and Grafana Loki.
+- It can accept logs from popular log collectors. See [these docs](https://docs.victoriametrics.com/victorialogs/data-ingestion/).
+- It is much easier to set up and operate compared to Elasticsearch and Grafana Loki.
   See [these docs](https://docs.victoriametrics.com/victorialogs/quickstart/).
-- VictoriaLogs provides easy yet powerful query language with full-text search across
+- It provides easy yet powerful query language with full-text search across
   all the [log fields](https://docs.victoriametrics.com/victorialogs/keyconcepts/#data-model).
   See [LogsQL docs](https://docs.victoriametrics.com/victorialogs/logsql/).
-- VictoriaLogs can be seamlessly combined with good old Unix tools for log analysis such as `grep`, `less`, `sort`, `jq`, etc.
+- It provides interactive command-line tool for querying VictoriaLogs - [vlogscli](https://docs.victoriametrics.com/victorialogs/querying/vlogscli/).
+- It can be seamlessly combined with good old Unix tools for log analysis such as `grep`, `less`, `sort`, `jq`, etc.
   See [these docs](https://docs.victoriametrics.com/victorialogs/querying/#command-line) for details.
-- VictoriaLogs capacity and performance scales linearly with the available resources (CPU, RAM, disk IO, disk space).
-  It runs smoothly on both Raspberry PI and a server with hundreds of CPU cores and terabytes of RAM.
-- VictoriaLogs can handle up to 30x bigger data volumes than Elasticsearch and Grafana Loki when running on the same hardware.
+- VictoriaLogs' capacity and performance scales linearly with the available resources (CPU, RAM, disk IO, disk space).
+  It runs smoothly on Raspberry PI and on servers with hundreds of CPU cores and terabytes of RAM.
+- It can handle up to 30x bigger data volumes than Elasticsearch and Grafana Loki when running on the same hardware.
   See [these docs](#benchmarks).
-- VictoriaLogs supports fast full-text search over high-cardinality [log fields](https://docs.victoriametrics.com/victorialogs/keyconcepts/#data-model)
-  such as `trace_id`, `user_id` and `ip`.
-- VictoriaLogs supports multitenancy - see [these docs](#multitenancy).
-- VictoriaLogs supports out-of-order logs' ingestion aka backfilling.
-- VictoriaLogs supports live tailing for newly ingested logs. See [these docs](https://docs.victoriametrics.com/victorialogs/querying/#live-tailing).
-- VictoriaLogs supports selecting surrounding logs in front and after the selected logs. See [these docs](https://docs.victoriametrics.com/victorialogs/logsql/#stream_context-pipe).
-- VictoriaLogs provides web UI for querying logs - see [these docs](https://docs.victoriametrics.com/victorialogs/querying/#web-ui).
+- It provides fast full-text search out of the box for [log fields](https://docs.victoriametrics.com/victorialogs/keyconcepts/#data-model)
+  with high cardinality (e.g. high number of unique values) such as `trace_id`, `user_id` and `ip`.
+- It supports multitenancy - see [these docs](#multitenancy).
+- It supports out-of-order logs' ingestion aka backfilling.
+- It supports live tailing for newly ingested logs. See [these docs](https://docs.victoriametrics.com/victorialogs/querying/#live-tailing).
+- It supports selecting surrounding logs in front and after the selected logs. See [these docs](https://docs.victoriametrics.com/victorialogs/logsql/#stream_context-pipe).
+- It provides web UI for querying logs - see [these docs](https://docs.victoriametrics.com/victorialogs/querying/#web-ui).
+- It provides [Grafana plugin for querying logs](https://docs.victoriametrics.com/victorialogs/victorialogs-datasource/).
 
 If you have questions about VictoriaLogs, then read [this FAQ](https://docs.victoriametrics.com/victorialogs/faq/).
 Also feel free asking any questions at [VictoriaMetrics community Slack chat](https://victoriametrics.slack.com/), 

docs/VictoriaLogs/querying/README.md

@@ -2,7 +2,7 @@
 via the following ways:
 
 - [Web UI](#web-ui) - a web-based UI for querying logs
-- [Visualization in Grafana](#visualization-in-grafana)
+- [Grafana plugin](#visualization-in-grafana)
 - [HTTP API](#http-api)
 - [Command-line interface](#command-line)
 
@@ -800,7 +800,10 @@ See also [command line interface](#command-line).
 
 ## Command-line
 
-VictoriaLogs integrates well with `curl` and other command-line tools during querying because of the following features:
+VictoriaLogs provides `vlogsqcli` interactive command-line tool for querying logs. See [these docs](https://docs.victoriametrics.com/victorialogs/querying/vlogscli/).
+
+VictoriaLogs [querying API](https://docs.victoriametrics.com/victorialogs/querying/#querying-logs) integrates well with `curl`
+and other Unix command-line tools because of the following features:
 
 - Matching log entries are sent to the response stream as soon as they are found.
   This allows forwarding the response stream to arbitrary [Unix pipes](https://en.wikipedia.org/wiki/Pipeline_(Unix))

docs/VictoriaLogs/querying/vlogscli.md

@@ -0,0 +1,76 @@
+---
+weight:
+title: vlogscli
+disableToc: true
+menu:
+  docs:
+    parent: "victorialogs-querying"
+    weight: 1
+---
+
+`vlogsqcli` is an interactive command-line tool for querying [VictoriaLogs](https://docs.victoriametrics.com/victorialogs/).
+This tool can be obtained from the linked release pages at the [changelog](https://docs.victoriametrics.com/victorialogs/changelog/)
+or from [docker images](https://hub.docker.com/r/victoriametrics/vlogscli/tags).
+
+By default `vlogscli` sends queries to [`http://localhost:8429/select/logsql/query`](https://docs.victoriametrics.com/victorialogs/querying/#querying-logs).
+The url to query can be changed via `-datasource.url` command-line flag. For example, the following command instructs
+`vlogsql` sending queries to `https://victoria-logs.some-domain.com/select/logsql/query`:
+
+```sh
+./vlogsql -datasource.url='https://victoria-logs.some-domain.com/select/logsql/query'
+```
+
+If some HTTP request headers must be passed to the querying API, then set `-header` command-line flag.
+For example, the following command starts `vlogsql`,
+which queries `(AccountID=123, ProjectID=456)` [tenant](https://docs.victoriametrics.com/victorialogs/#multitenancy):
+
+```sh
+./vlogsql -header='AccountID: 123' -header='ProjectID: 456'
+```
+
+After the start `vlogsql` provides a prompt for writing [LogsQL](https://docs.victoriametrics.com/victorialogs/logsql/) queries.
+The query can be multi-line. The is sent to VictoriaLogs as soon as it contains `;` at the end or if a blank line follows the query.
+For example:
+
+```sh
+;> _time:1y | count();
+executing [_time:1y | stats count(*) as "count(*)"]...
+{
+  "count(*)": "1923019991"
+}
+duration: 0.688s
+```
+
+Query execution can be interrupted at any time by pressing `Ctrl+C`.
+
+Type `q`, `quit` or `exit` and the press `Enter` for exit from `vlogsql`.
+
+If the query response exceeds vertical screen space, the `vlogsql` pipes query response to `less` utility,
+so you can scroll the response as needed. This allows executing queries, which potentially
+may return billions of rows, without any problems at both VictoriaMetrics and `vlogsql` sides,
+thanks to the way how `less` interacts with [`/select/logsql/query`](https://docs.victoriametrics.com/victorialogs/querying/#querying-logs):
+
+- `less` reads the response when needed, e.g. when you scroll it down.
+  `less` pauses reading the response when you stop scrolling. VictoriaLogs pauses processing the query
+  when `less` stops reading the response, and automatically resumes processing the response
+  when `less` continues reading it.
+- `less` closes the response stream after exit from scroll mode (e.g. by typing `q`).
+  VictoriaLogs stops query processing and frees up all the associated resources
+  after the response stream is closed.
+
+See also [`less` docs](https://man7.org/linux/man-pages/man1/less.1.html) and
+[command-line integration docs for VictoriaMetrics](https://docs.victoriametrics.com/victorialogs/querying/#command-line).
+
+
+## Query history
+
+`vlogsql` supports query history - press `up` and `down` keys for navigating the history.
+By default the history is stored in the `vlogsql-history` file at the directory where `vlogsql` runs,
+so the history is available between `vlogsql` runs.
+The path to the file can be changed via `-historyFile` command-line flag.
+
+Quick tip: type some text and then press `Ctrl+R` for searching queries with the given text in the history.
+Press `Ctrl+R` multiple times for searching other matching queries in the history.
+Press `Enter` when the needed query is found in order to execute it.
+Press `Ctrl+C` for exit from the `search history` mode.
+See also [other available shortcuts](https://github.com/chzyer/readline/blob/f533ef1caae91a1fcc90875ff9a5a030f0237c6a/doc/shortcut.md).

go.mod

@@ -18,11 +18,13 @@ require (
 	github.com/bmatcuk/doublestar/v4 v4.6.1
 	github.com/cespare/xxhash/v2 v2.3.0
 	github.com/cheggaaa/pb/v3 v3.1.5
+	github.com/ergochat/readline v0.1.3
 	github.com/gogo/protobuf v1.3.2
 	github.com/golang/snappy v0.0.4
 	github.com/googleapis/gax-go/v2 v2.13.0
 	github.com/influxdata/influxdb v1.11.6
 	github.com/klauspost/compress v1.17.10
+	github.com/mattn/go-isatty v0.0.20
 	github.com/prometheus/prometheus v0.54.1
 	github.com/urfave/cli/v2 v2.27.4
 	github.com/valyala/fastjson v1.6.4
@@ -87,7 +89,6 @@ require (
 	github.com/json-iterator/go v1.1.12 // indirect
 	github.com/kylelemons/godebug v1.1.0 // indirect
 	github.com/mattn/go-colorable v0.1.13 // indirect
-	github.com/mattn/go-isatty v0.0.20 // indirect
 	github.com/mattn/go-runewidth v0.0.16 // indirect
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/modern-go/reflect2 v1.0.2 // indirect

go.sum

@@ -182,6 +182,8 @@ github.com/envoyproxy/go-control-plane v0.13.0/go.mod h1:GRaKG3dwvFoTg4nj7aXdZnv
 github.com/envoyproxy/protoc-gen-validate v0.1.0/go.mod h1:iSmxcyjqTsJpI2R4NaDN7+kN2VEUnK/pcBlmesArF7c=
 github.com/envoyproxy/protoc-gen-validate v1.1.0 h1:tntQDh69XqOCOZsDz0lVJQez/2L6Uu2PdjCQwWCJ3bM=
 github.com/envoyproxy/protoc-gen-validate v1.1.0/go.mod h1:sXRDRVmzEbkM7CVcM06s9shE/m23dg3wzjl0UWqJ2q4=
+github.com/ergochat/readline v0.1.3 h1:/DytGTmwdUJcLAe3k3VJgowh5vNnsdifYT6uVaf4pSo=
+github.com/ergochat/readline v0.1.3/go.mod h1:o3ux9QLHLm77bq7hDB21UTm6HlV2++IPDMfIfKDuOgY=
 github.com/facette/natsort v0.0.0-20181210072756-2cd4dd1e2dcb h1:IT4JYU7k4ikYg1SCxNI1/Tieq/NFvh6dzLdgi7eu0tM=
 github.com/facette/natsort v0.0.0-20181210072756-2cd4dd1e2dcb/go.mod h1:bH6Xx7IW64qjjJq8M2u4dxNaBiDfKK+z/3eGDpXEQhc=
 github.com/fatih/color v1.17.0 h1:GlRw1BRJxkpqUCBKzKOw098ed57fEsKeNjpTe3cSjK4=

lib/logger/logger.go

@@ -37,13 +37,27 @@ var (
 //
 // There is no need in calling Init from tests.
 func Init() {
+	initInternal(true)
+}
+
+// InitNoLogFlags initializes the logger without writing flags to stdout
+//
+// InitNoLogFlags must be called after flag.Parse()
+func InitNoLogFlags() {
+	initInternal(false)
+}
+
+func initInternal(logFlags bool) {
 	setLoggerJSONFields()
 	setLoggerOutput()
 	validateLoggerLevel()
 	validateLoggerFormat()
 	initTimezone()
 	go logLimiterCleaner()
-	logAllFlags()
+
+	if logFlags {
+		logAllFlags()
+	}
 }
 
 func initTimezone() {

lib/logstorage/parser.go

@@ -841,7 +841,7 @@ func parseGenericFilter(lex *lexer, fieldName string) (filter, error) {
 		return f, nil
 	case lex.isKeyword("("):
 		if !lex.isSkippedSpace && !lex.isPrevToken("", ":", "(", "!", "-", "not") {
-			return nil, fmt.Errorf("missing whitespace before the search word %q", lex.prevToken)
+			return nil, fmt.Errorf("missing whitespace after the search word %q", lex.prevToken)
 		}
 		return parseParensFilter(lex, fieldName)
 	case lex.isKeyword(">"):

vendor/github.com/ergochat/readline/.check-gofmt.sh

@@ -0,0 +1,14 @@
+#!/bin/bash
+
+# exclude vendor/
+SOURCES="*.go internal/ example/"
+
+if [ "$1" = "--fix" ]; then
+	exec gofmt -s -w $SOURCES
+fi
+
+if [ -n "$(gofmt -s -l $SOURCES)" ]; then
+	echo "Go code is not formatted correctly with \`gofmt -s\`:"
+	gofmt -s -d $SOURCES
+	exit 1
+fi

vendor/github.com/ergochat/readline/.gitignore

@@ -0,0 +1,2 @@
+.vscode/*
+*.swp

vendor/github.com/ergochat/readline/LICENSE

@@ -0,0 +1,22 @@
+The MIT License (MIT)
+
+Copyright (c) 2015 Chzyer
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+

vendor/github.com/ergochat/readline/Makefile

@@ -0,0 +1,18 @@
+.PHONY: all test examples ci gofmt
+
+all: ci
+
+ci: test examples
+
+test:
+	go test -race ./...
+	go vet ./...
+	./.check-gofmt.sh
+
+examples:
+	GOOS=linux go build -o /dev/null example/readline-demo/readline-demo.go
+	GOOS=windows go build -o /dev/null example/readline-demo/readline-demo.go
+	GOOS=darwin go build -o /dev/null example/readline-demo/readline-demo.go
+
+gofmt:
+	./.check-gofmt.sh --fix

vendor/github.com/ergochat/readline/README.md

@@ -0,0 +1,47 @@
+readline
+========
+
+[![Godoc](https://godoc.org/github.com/ergochat/readline?status.svg)](https://godoc.org/github.com/ergochat/readline)
+
+This is a pure Go implementation of functionality comparable to [GNU Readline](https://en.wikipedia.org/wiki/GNU_Readline), i.e. line editing and command history for simple TUI programs.
+
+It is a fork of [chzyer/readline](https://github.com/chzyer/readline).
+
+* Relative to the upstream repository, it is actively maintained and has numerous bug fixes
+   - See our [changelog](docs/CHANGELOG.md) for details on fixes and improvements
+   - See our [migration guide](docs/MIGRATING.md) for advice on how to migrate from upstream
+* Relative to [x/term](https://pkg.go.dev/golang.org/x/term), it has more features (e.g. tab-completion)
+* In use by multiple projects: [gopass](https://github.com/gopasspw/gopass), [fq](https://github.com/wader/fq), and [ircdog](https://github.com/ergochat/ircdog)
+
+
+```go
+package main
+
+import (
+	"fmt"
+	"log"
+
+	"github.com/ergochat/readline"
+)
+
+func main() {
+	// see readline.NewFromConfig for advanced options:
+	rl, err := readline.New("> ")
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer rl.Close()
+	log.SetOutput(rl.Stderr()) // redraw the prompt correctly after log output
+
+	for {
+		line, err := rl.ReadLine()
+		// `err` is either nil, io.EOF, readline.ErrInterrupt, or an unexpected
+		// condition in stdin:
+		if err != nil {
+			return
+		}
+		// `line` is returned without the terminating \n or CRLF:
+		fmt.Fprintf(rl, "you wrote: %s\n", line)
+	}
+}
+```

vendor/github.com/ergochat/readline/complete.go

@@ -0,0 +1,499 @@
+package readline
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"sync/atomic"
+
+	"github.com/ergochat/readline/internal/platform"
+	"github.com/ergochat/readline/internal/runes"
+)
+
+type AutoCompleter interface {
+	// Readline will pass the whole line and current offset to it
+	// Completer need to pass all the candidates, and how long they shared the same characters in line
+	// Example:
+	//   [go, git, git-shell, grep]
+	//   Do("g", 1) => ["o", "it", "it-shell", "rep"], 1
+	//   Do("gi", 2) => ["t", "t-shell"], 2
+	//   Do("git", 3) => ["", "-shell"], 3
+	Do(line []rune, pos int) (newLine [][]rune, length int)
+}
+
+type opCompleter struct {
+	w  *terminal
+	op *operation
+
+	inCompleteMode atomic.Uint32 // this is read asynchronously from wrapWriter
+	inSelectMode   bool
+
+	candidate         [][]rune // list of candidates
+	candidateSource   []rune   // buffer string when tab was pressed
+	candidateOff      int      // num runes in common from buf where candidate start
+	candidateChoice   int      // absolute index of the chosen candidate (indexing the candidate array which might not all display in current page)
+	candidateColNum   int      // num columns candidates take 0..wraps, 1 col, 2 cols etc.
+	candidateColWidth int      // width of candidate columns
+	linesAvail        int      // number of lines available below the user's prompt which could be used for rendering the completion
+	pageStartIdx      []int    // start index in the candidate array on each page (candidatePageStart[i] = absolute idx of the first candidate on page i)
+	curPage           int      // index of the current page
+}
+
+func newOpCompleter(w *terminal, op *operation) *opCompleter {
+	return &opCompleter{
+		w:  w,
+		op: op,
+	}
+}
+
+func (o *opCompleter) doSelect() {
+	if len(o.candidate) == 1 {
+		o.op.buf.WriteRunes(o.candidate[0])
+		o.ExitCompleteMode(false)
+		return
+	}
+	o.nextCandidate()
+	o.CompleteRefresh()
+}
+
+// Convert absolute index of the chosen candidate to a page-relative index
+func (o *opCompleter) candidateChoiceWithinPage() int {
+	return o.candidateChoice - o.pageStartIdx[o.curPage]
+}
+
+// Given a page relative index of the chosen candidate, update the absolute index
+func (o *opCompleter) updateAbsolutechoice(choiceWithinPage int) {
+	o.candidateChoice = choiceWithinPage + o.pageStartIdx[o.curPage]
+}
+
+// Move selection to the next candidate, updating page if necessary
+// Note: we don't allow passing arbitrary offset to this function because, e.g.,
+// we don't have the 3rd page offset initialized when the user is just seeing the first page,
+// so we only allow users to navigate into the 2nd page but not to an arbirary page as a result
+// of calling this method
+func (o *opCompleter) nextCandidate() {
+	o.candidateChoice = (o.candidateChoice + 1) % len(o.candidate)
+	// Wrapping around
+	if o.candidateChoice == 0 {
+		o.curPage = 0
+		return
+	}
+	// Going to next page
+	if o.candidateChoice == o.pageStartIdx[o.curPage+1] {
+		o.curPage += 1
+	}
+}
+
+// Move selection to the next ith col in the current line, wrapping to the line start/end if needed
+func (o *opCompleter) nextCol(i int) {
+	// If o.candidateColNum == 1 or 0, there is only one col per line and this is a noop
+	if o.candidateColNum > 1 {
+		idxWithinPage := o.candidateChoiceWithinPage()
+		curLine := idxWithinPage / o.candidateColNum
+		offsetInLine := idxWithinPage % o.candidateColNum
+		nextOffset := offsetInLine + i
+		nextOffset %= o.candidateColNum
+		if nextOffset < 0 {
+			nextOffset += o.candidateColNum
+		}
+
+		nextIdxWithinPage := curLine*o.candidateColNum + nextOffset
+		o.updateAbsolutechoice(nextIdxWithinPage)
+	}
+}
+
+// Move selection to the line below
+func (o *opCompleter) nextLine() {
+	colNum := 1
+	if o.candidateColNum > 1 {
+		colNum = o.candidateColNum
+	}
+
+	idxWithinPage := o.candidateChoiceWithinPage()
+
+	idxWithinPage += colNum
+	if idxWithinPage >= o.getMatrixSize() {
+		idxWithinPage -= o.getMatrixSize()
+	} else if idxWithinPage >= o.numCandidateCurPage() {
+		idxWithinPage += colNum
+		idxWithinPage -= o.getMatrixSize()
+	}
+
+	o.updateAbsolutechoice(idxWithinPage)
+}
+
+// Move selection to the line above
+func (o *opCompleter) prevLine() {
+	colNum := 1
+	if o.candidateColNum > 1 {
+		colNum = o.candidateColNum
+	}
+
+	idxWithinPage := o.candidateChoiceWithinPage()
+
+	idxWithinPage -= colNum
+	if idxWithinPage < 0 {
+		idxWithinPage += o.getMatrixSize()
+		if idxWithinPage >= o.numCandidateCurPage() {
+			idxWithinPage -= colNum
+		}
+	}
+
+	o.updateAbsolutechoice(idxWithinPage)
+}
+
+// Move selection to the start of the current line
+func (o *opCompleter) lineStart() {
+	if o.candidateColNum > 1 {
+		idxWithinPage := o.candidateChoiceWithinPage()
+		lineOffset := idxWithinPage % o.candidateColNum
+		idxWithinPage -= lineOffset
+		o.updateAbsolutechoice(idxWithinPage)
+	}
+}
+
+// Move selection to the end of the current line
+func (o *opCompleter) lineEnd() {
+	if o.candidateColNum > 1 {
+		idxWithinPage := o.candidateChoiceWithinPage()
+		offsetToLineEnd := o.candidateColNum - idxWithinPage%o.candidateColNum - 1
+		idxWithinPage += offsetToLineEnd
+		o.updateAbsolutechoice(idxWithinPage)
+		if o.candidateChoice >= len(o.candidate) {
+			o.candidateChoice = len(o.candidate) - 1
+		}
+	}
+}
+
+// Move to the next page if possible, returning selection to the first item in the page
+func (o *opCompleter) nextPage() {
+	// Check that this is not the last page already
+	nextPageStart := o.pageStartIdx[o.curPage+1]
+	if nextPageStart < len(o.candidate) {
+		o.curPage += 1
+		o.candidateChoice = o.pageStartIdx[o.curPage]
+	}
+}
+
+// Move to the previous page if possible, returning selection to the first item in the page
+func (o *opCompleter) prevPage() {
+	if o.curPage > 0 {
+		o.curPage -= 1
+		o.candidateChoice = o.pageStartIdx[o.curPage]
+	}
+}
+
+// OnComplete returns true if complete mode is available. Used to ring bell
+// when tab pressed if cannot do complete for reason such as width unknown
+// or no candidates available.
+func (o *opCompleter) OnComplete() (ringBell bool) {
+	tWidth, tHeight := o.w.GetWidthHeight()
+	if tWidth == 0 || tHeight < 3 {
+		return false
+	}
+	if o.IsInCompleteSelectMode() {
+		o.doSelect()
+		return true
+	}
+
+	buf := o.op.buf
+	rs := buf.Runes()
+
+	// If in complete mode and nothing else typed then we must be entering select mode
+	if o.IsInCompleteMode() && o.candidateSource != nil && runes.Equal(rs, o.candidateSource) {
+		if len(o.candidate) > 1 {
+			same, size := runes.Aggregate(o.candidate)
+			if size > 0 {
+				buf.WriteRunes(same)
+				o.ExitCompleteMode(false)
+				return false // partial completion so ring the bell
+			}
+		}
+		o.EnterCompleteSelectMode()
+		o.doSelect()
+		return true
+	}
+
+	newLines, offset := o.op.GetConfig().AutoComplete.Do(rs, buf.idx)
+	if len(newLines) == 0 || (len(newLines) == 1 && len(newLines[0]) == 0) {
+		o.ExitCompleteMode(false)
+		return false // will ring bell on initial tab press
+	}
+	if o.candidateOff > offset {
+		// part of buffer we are completing has changed. Example might be that we were completing "ls" and
+		// user typed space so we are no longer completing "ls" but now we are completing an argument of
+		// the ls command. Instead of continuing in complete mode, we exit.
+		o.ExitCompleteMode(false)
+		return true
+	}
+	o.candidateSource = rs
+
+	// only Aggregate candidates in non-complete mode
+	if !o.IsInCompleteMode() {
+		if len(newLines) == 1 {
+			// not yet in complete mode but only 1 candidate so complete it
+			buf.WriteRunes(newLines[0])
+			o.ExitCompleteMode(false)
+			return true
+		}
+
+		// check if all candidates have common prefix and return it and its size
+		same, size := runes.Aggregate(newLines)
+		if size > 0 {
+			buf.WriteRunes(same)
+			o.ExitCompleteMode(false)
+			return false // partial completion so ring the bell
+		}
+	}
+
+	// otherwise, we just enter complete mode (which does a refresh)
+	o.EnterCompleteMode(offset, newLines)
+	return true
+}
+
+func (o *opCompleter) IsInCompleteSelectMode() bool {
+	return o.inSelectMode
+}
+
+func (o *opCompleter) IsInCompleteMode() bool {
+	return o.inCompleteMode.Load() == 1
+}
+
+func (o *opCompleter) HandleCompleteSelect(r rune) (stayInMode bool) {
+	next := true
+	switch r {
+	case CharEnter, CharCtrlJ:
+		next = false
+		o.op.buf.WriteRunes(o.candidate[o.candidateChoice])
+		o.ExitCompleteMode(false)
+	case CharLineStart:
+		o.lineStart()
+	case CharLineEnd:
+		o.lineEnd()
+	case CharBackspace:
+		o.ExitCompleteSelectMode()
+		next = false
+	case CharTab:
+		o.nextCandidate()
+	case CharForward:
+		o.nextCol(1)
+	case CharBell, CharInterrupt:
+		o.ExitCompleteMode(true)
+		next = false
+	case CharNext:
+		o.nextLine()
+	case CharBackward, MetaShiftTab:
+		o.nextCol(-1)
+	case CharPrev:
+		o.prevLine()
+	case 'j', 'J':
+		o.prevPage()
+	case 'k', 'K':
+		o.nextPage()
+	default:
+		next = false
+		o.ExitCompleteSelectMode()
+	}
+	if next {
+		o.CompleteRefresh()
+		return true
+	}
+	return false
+}
+
+func (o *opCompleter) getMatrixSize() int {
+	colNum := 1
+	if o.candidateColNum > 1 {
+		colNum = o.candidateColNum
+	}
+	line := o.getMatrixNumRows()
+	return line * colNum
+}
+
+// Number of candidate that could fit on current page
+func (o *opCompleter) numCandidateCurPage() int {
+	// Safety: we will always render the first page, and whenever we finished rendering page i,
+	// we always populate o.candidatePageStart through at least i + 1, so when this is called, we
+	// always know the start of the next page
+	return o.pageStartIdx[o.curPage+1] - o.pageStartIdx[o.curPage]
+}
+
+// Get number of rows of current page viewed as a matrix of candidates
+func (o *opCompleter) getMatrixNumRows() int {
+	candidateCurPage := o.numCandidateCurPage()
+	// Normal case where there is no wrap
+	if o.candidateColNum > 1 {
+		numLine := candidateCurPage / o.candidateColNum
+		if candidateCurPage%o.candidateColNum != 0 {
+			numLine++
+		}
+		return numLine
+	}
+
+	// Now since there are wraps, each candidate will be put on its own line, so the number of lines is just the number of candidate
+	return candidateCurPage
+}
+
+// setColumnInfo calculates column width and number of columns required
+// to present the list of candidates on the terminal.
+func (o *opCompleter) setColumnInfo() {
+	same := o.op.buf.RuneSlice(-o.candidateOff)
+	sameWidth := runes.WidthAll(same)
+
+	colWidth := 0
+	for _, c := range o.candidate {
+		w := sameWidth + runes.WidthAll(c)
+		if w > colWidth {
+			colWidth = w
+		}
+	}
+	colWidth++ // whitespace between cols
+
+	tWidth, _ := o.w.GetWidthHeight()
+
+	// -1 to avoid end of line issues
+	width := tWidth - 1
+	colNum := width / colWidth
+	if colNum != 0 {
+		colWidth += (width - (colWidth * colNum)) / colNum
+	}
+
+	o.candidateColNum = colNum
+	o.candidateColWidth = colWidth
+}
+
+// CompleteRefresh is used for completemode and selectmode
+func (o *opCompleter) CompleteRefresh() {
+	if !o.IsInCompleteMode() {
+		return
+	}
+
+	buf := bufio.NewWriter(o.w)
+	// calculate num lines from cursor pos to where choices should be written
+	lineCnt := o.op.buf.CursorLineCount()
+	buf.Write(bytes.Repeat([]byte("\n"), lineCnt)) // move down from cursor to start of candidates
+	buf.WriteString("\033[J")
+
+	same := o.op.buf.RuneSlice(-o.candidateOff)
+	tWidth, _ := o.w.GetWidthHeight()
+
+	colIdx := 0
+	lines := 0
+	sameWidth := runes.WidthAll(same)
+
+	// Show completions for the current page
+	idx := o.pageStartIdx[o.curPage]
+	for ; idx < len(o.candidate); idx++ {
+		// If writing the current candidate would overflow the page,
+		// we know that it is the start of the next page.
+		if colIdx == 0 && lines == o.linesAvail {
+			if o.curPage == len(o.pageStartIdx)-1 {
+				o.pageStartIdx = append(o.pageStartIdx, idx)
+			}
+			break
+		}
+
+		c := o.candidate[idx]
+		inSelect := idx == o.candidateChoice && o.IsInCompleteSelectMode()
+		cWidth := sameWidth + runes.WidthAll(c)
+		cLines := 1
+		if tWidth > 0 {
+			sWidth := 0
+			if platform.IsWindows && inSelect {
+				sWidth = 1 // adjust for hightlighting on Windows
+			}
+			cLines = (cWidth + sWidth) / tWidth
+			if (cWidth+sWidth)%tWidth > 0 {
+				cLines++
+			}
+		}
+
+		if lines > 0 && colIdx == 0 {
+			// After line 1, if we're printing to the first column
+			// goto a new line. We do it here, instead of at the end
+			// of the loop, to avoid the last \n taking up a blank
+			// line at the end and stealing realestate.
+			buf.WriteString("\n")
+		}
+
+		if inSelect {
+			buf.WriteString("\033[30;47m")
+		}
+
+		buf.WriteString(string(same))
+		buf.WriteString(string(c))
+		if o.candidateColNum >= 1 {
+			// only output spaces between columns if everything fits
+			buf.Write(bytes.Repeat([]byte(" "), o.candidateColWidth-cWidth))
+		}
+
+		if inSelect {
+			buf.WriteString("\033[0m")
+		}
+
+		colIdx++
+		if colIdx >= o.candidateColNum {
+			lines += cLines
+			colIdx = 0
+			if platform.IsWindows {
+				// Windows EOL edge-case.
+				buf.WriteString("\b")
+			}
+		}
+	}
+
+	if idx == len(o.candidate) {
+		// Book-keeping for the last page.
+		o.pageStartIdx = append(o.pageStartIdx, len(o.candidate))
+	}
+
+	if colIdx > 0 {
+		lines++ // mid-line so count it.
+	}
+
+	// Show the guidance if there are more pages
+	if idx != len(o.candidate) || o.curPage > 0 {
+		buf.WriteString("\n-- (j: prev page) (k: next page) --")
+		lines++
+	}
+
+	// wrote out choices over "lines", move back to cursor (positioned at index)
+	fmt.Fprintf(buf, "\033[%dA", lines)
+	buf.Write(o.op.buf.getBackspaceSequence())
+	buf.Flush()
+}
+
+func (o *opCompleter) EnterCompleteSelectMode() {
+	o.inSelectMode = true
+	o.candidateChoice = -1
+}
+
+func (o *opCompleter) EnterCompleteMode(offset int, candidate [][]rune) {
+	o.inCompleteMode.Store(1)
+	o.candidate = candidate
+	o.candidateOff = offset
+	o.setColumnInfo()
+	o.initPage()
+	o.CompleteRefresh()
+}
+
+func (o *opCompleter) initPage() {
+	_, tHeight := o.w.GetWidthHeight()
+	buflineCnt := o.op.buf.LineCount()      // lines taken by buffer content
+	o.linesAvail = tHeight - buflineCnt - 1 // lines available without scrolling buffer off screen, reserve one line for the guidance message
+	o.pageStartIdx = []int{0}               // first page always start at 0
+	o.curPage = 0
+}
+
+func (o *opCompleter) ExitCompleteSelectMode() {
+	o.inSelectMode = false
+	o.candidateChoice = -1
+}
+
+func (o *opCompleter) ExitCompleteMode(revent bool) {
+	o.inCompleteMode.Store(0)
+	o.candidate = nil
+	o.candidateOff = -1
+	o.candidateSource = nil
+	o.ExitCompleteSelectMode()
+}

vendor/github.com/ergochat/readline/complete_helper.go

@@ -0,0 +1,156 @@
+package readline
+
+import (
+	"bytes"
+	"strings"
+
+	"github.com/ergochat/readline/internal/runes"
+)
+
+// PrefixCompleter implements AutoCompleter via a recursive tree.
+type PrefixCompleter struct {
+	// Name is the name of a command, subcommand, or argument eligible for completion.
+	Name string
+	// Callback is optional; if defined, it takes the current line and returns
+	// a list of possible completions associated with the current node (i.e.
+	// in place of Name).
+	Callback func(string) []string
+	// Children is a list of possible completions that can follow the current node.
+	Children []*PrefixCompleter
+
+	nameRunes []rune // just a cache
+}
+
+var _ AutoCompleter = (*PrefixCompleter)(nil)
+
+func (p *PrefixCompleter) Tree(prefix string) string {
+	buf := bytes.NewBuffer(nil)
+	p.print(prefix, 0, buf)
+	return buf.String()
+}
+
+func prefixPrint(p *PrefixCompleter, prefix string, level int, buf *bytes.Buffer) {
+	if strings.TrimSpace(p.Name) != "" {
+		buf.WriteString(prefix)
+		if level > 0 {
+			buf.WriteString("├")
+			buf.WriteString(strings.Repeat("─", (level*4)-2))
+			buf.WriteString(" ")
+		}
+		buf.WriteString(p.Name)
+		buf.WriteByte('\n')
+		level++
+	}
+	for _, ch := range p.Children {
+		ch.print(prefix, level, buf)
+	}
+}
+
+func (p *PrefixCompleter) print(prefix string, level int, buf *bytes.Buffer) {
+	prefixPrint(p, prefix, level, buf)
+}
+
+func (p *PrefixCompleter) getName() []rune {
+	if p.nameRunes == nil {
+		if p.Name != "" {
+			p.nameRunes = []rune(p.Name)
+		} else {
+			p.nameRunes = make([]rune, 0)
+		}
+	}
+	return p.nameRunes
+}
+
+func (p *PrefixCompleter) getDynamicNames(line []rune) [][]rune {
+	var result [][]rune
+	for _, name := range p.Callback(string(line)) {
+		nameRunes := []rune(name)
+		nameRunes = append(nameRunes, ' ')
+		result = append(result, nameRunes)
+	}
+	return result
+}
+
+func (p *PrefixCompleter) SetChildren(children []*PrefixCompleter) {
+	p.Children = children
+}
+
+func NewPrefixCompleter(pc ...*PrefixCompleter) *PrefixCompleter {
+	return PcItem("", pc...)
+}
+
+func PcItem(name string, pc ...*PrefixCompleter) *PrefixCompleter {
+	name += " "
+	result := &PrefixCompleter{
+		Name:     name,
+		Children: pc,
+	}
+	result.getName() // initialize nameRunes member
+	return result
+}
+
+func PcItemDynamic(callback func(string) []string, pc ...*PrefixCompleter) *PrefixCompleter {
+	return &PrefixCompleter{
+		Callback: callback,
+		Children: pc,
+	}
+}
+
+func (p *PrefixCompleter) Do(line []rune, pos int) (newLine [][]rune, offset int) {
+	return doInternal(p, line, pos, line)
+}
+
+func doInternal(p *PrefixCompleter, line []rune, pos int, origLine []rune) (newLine [][]rune, offset int) {
+	line = runes.TrimSpaceLeft(line[:pos])
+	goNext := false
+	var lineCompleter *PrefixCompleter
+	for _, child := range p.Children {
+		var childNames [][]rune
+		if child.Callback != nil {
+			childNames = child.getDynamicNames(origLine)
+		} else {
+			childNames = make([][]rune, 1)
+			childNames[0] = child.getName()
+		}
+
+		for _, childName := range childNames {
+			if len(line) >= len(childName) {
+				if runes.HasPrefix(line, childName) {
+					if len(line) == len(childName) {
+						newLine = append(newLine, []rune{' '})
+					} else {
+						newLine = append(newLine, childName)
+					}
+					offset = len(childName)
+					lineCompleter = child
+					goNext = true
+				}
+			} else {
+				if runes.HasPrefix(childName, line) {
+					newLine = append(newLine, childName[len(line):])
+					offset = len(line)
+					lineCompleter = child
+				}
+			}
+		}
+	}
+
+	if len(newLine) != 1 {
+		return
+	}
+
+	tmpLine := make([]rune, 0, len(line))
+	for i := offset; i < len(line); i++ {
+		if line[i] == ' ' {
+			continue
+		}
+
+		tmpLine = append(tmpLine, line[i:]...)
+		return doInternal(lineCompleter, tmpLine, len(tmpLine), origLine)
+	}
+
+	if goNext {
+		return doInternal(lineCompleter, nil, 0, origLine)
+	}
+	return
+}

vendor/github.com/ergochat/readline/history.go

@@ -0,0 +1,330 @@
+package readline
+
+import (
+	"bufio"
+	"container/list"
+	"fmt"
+	"os"
+	"strings"
+	"sync"
+
+	"github.com/ergochat/readline/internal/runes"
+)
+
+type hisItem struct {
+	Source  []rune
+	Version int64
+	Tmp     []rune
+}
+
+func (h *hisItem) Clean() {
+	h.Source = nil
+	h.Tmp = nil
+}
+
+type opHistory struct {
+	operation  *operation
+	history    *list.List
+	historyVer int64
+	current    *list.Element
+	fd         *os.File
+	fdLock     sync.Mutex
+	enable     bool
+}
+
+func newOpHistory(operation *operation) (o *opHistory) {
+	o = &opHistory{
+		operation: operation,
+		history:   list.New(),
+		enable:    true,
+	}
+	o.initHistory()
+	return o
+}
+
+func (o *opHistory) isEnabled() bool {
+	return o.enable && o.operation.GetConfig().HistoryLimit > 0
+}
+
+func (o *opHistory) Reset() {
+	o.history = list.New()
+	o.current = nil
+}
+
+func (o *opHistory) initHistory() {
+	cfg := o.operation.GetConfig()
+	if cfg.HistoryFile != "" {
+		o.historyUpdatePath(cfg)
+	}
+}
+
+// only called by newOpHistory
+func (o *opHistory) historyUpdatePath(cfg *Config) {
+	o.fdLock.Lock()
+	defer o.fdLock.Unlock()
+	f, err := os.OpenFile(cfg.HistoryFile, os.O_APPEND|os.O_CREATE|os.O_RDWR, 0666)
+	if err != nil {
+		return
+	}
+	o.fd = f
+	r := bufio.NewReader(o.fd)
+	total := 0
+	for ; ; total++ {
+		line, err := r.ReadString('\n')
+		if err != nil {
+			break
+		}
+		// ignore the empty line
+		line = strings.TrimSpace(line)
+		if len(line) == 0 {
+			continue
+		}
+		o.Push([]rune(line))
+		o.Compact()
+	}
+	if total > cfg.HistoryLimit {
+		o.rewriteLocked()
+	}
+	o.historyVer++
+	o.Push(nil)
+	return
+}
+
+func (o *opHistory) Compact() {
+	cfg := o.operation.GetConfig()
+	for o.history.Len() > cfg.HistoryLimit && o.history.Len() > 0 {
+		o.history.Remove(o.history.Front())
+	}
+}
+
+func (o *opHistory) Rewrite() {
+	o.fdLock.Lock()
+	defer o.fdLock.Unlock()
+	o.rewriteLocked()
+}
+
+func (o *opHistory) rewriteLocked() {
+	cfg := o.operation.GetConfig()
+	if cfg.HistoryFile == "" {
+		return
+	}
+
+	tmpFile := cfg.HistoryFile + ".tmp"
+	fd, err := os.OpenFile(tmpFile, os.O_CREATE|os.O_WRONLY|os.O_TRUNC|os.O_APPEND, 0666)
+	if err != nil {
+		return
+	}
+
+	buf := bufio.NewWriter(fd)
+	for elem := o.history.Front(); elem != nil; elem = elem.Next() {
+		buf.WriteString(string(elem.Value.(*hisItem).Source) + "\n")
+	}
+	buf.Flush()
+
+	// replace history file
+	if err = os.Rename(tmpFile, cfg.HistoryFile); err != nil {
+		fd.Close()
+		return
+	}
+
+	if o.fd != nil {
+		o.fd.Close()
+	}
+	// fd is write only, just satisfy what we need.
+	o.fd = fd
+}
+
+func (o *opHistory) Close() {
+	o.fdLock.Lock()
+	defer o.fdLock.Unlock()
+	if o.fd != nil {
+		o.fd.Close()
+	}
+}
+
+func (o *opHistory) FindBck(isNewSearch bool, rs []rune, start int) (int, *list.Element) {
+	for elem := o.current; elem != nil; elem = elem.Prev() {
+		item := o.showItem(elem.Value)
+		if isNewSearch {
+			start += len(rs)
+		}
+		if elem == o.current {
+			if len(item) >= start {
+				item = item[:start]
+			}
+		}
+		idx := runes.IndexAllBckEx(item, rs, o.operation.GetConfig().HistorySearchFold)
+		if idx < 0 {
+			continue
+		}
+		return idx, elem
+	}
+	return -1, nil
+}
+
+func (o *opHistory) FindFwd(isNewSearch bool, rs []rune, start int) (int, *list.Element) {
+	for elem := o.current; elem != nil; elem = elem.Next() {
+		item := o.showItem(elem.Value)
+		if isNewSearch {
+			start -= len(rs)
+			if start < 0 {
+				start = 0
+			}
+		}
+		if elem == o.current {
+			if len(item)-1 >= start {
+				item = item[start:]
+			} else {
+				continue
+			}
+		}
+		idx := runes.IndexAllEx(item, rs, o.operation.GetConfig().HistorySearchFold)
+		if idx < 0 {
+			continue
+		}
+		if elem == o.current {
+			idx += start
+		}
+		return idx, elem
+	}
+	return -1, nil
+}
+
+func (o *opHistory) showItem(obj interface{}) []rune {
+	item := obj.(*hisItem)
+	if item.Version == o.historyVer {
+		return item.Tmp
+	}
+	return item.Source
+}
+
+func (o *opHistory) Prev() []rune {
+	if o.current == nil {
+		return nil
+	}
+	current := o.current.Prev()
+	if current == nil {
+		return nil
+	}
+	o.current = current
+	return runes.Copy(o.showItem(current.Value))
+}
+
+func (o *opHistory) Next() ([]rune, bool) {
+	if o.current == nil {
+		return nil, false
+	}
+	current := o.current.Next()
+	if current == nil {
+		return nil, false
+	}
+
+	o.current = current
+	return runes.Copy(o.showItem(current.Value)), true
+}
+
+// Disable the current history
+func (o *opHistory) Disable() {
+	o.enable = false
+}
+
+// Enable the current history
+func (o *opHistory) Enable() {
+	o.enable = true
+}
+
+func (o *opHistory) debug() {
+	debugPrint("-------")
+	for item := o.history.Front(); item != nil; item = item.Next() {
+		debugPrint(fmt.Sprintf("%+v", item.Value))
+	}
+}
+
+// save history
+func (o *opHistory) New(current []rune) (err error) {
+	if !o.isEnabled() {
+		return nil
+	}
+
+	current = runes.Copy(current)
+
+	// if just use last command without modify
+	// just clean lastest history
+	if back := o.history.Back(); back != nil {
+		prev := back.Prev()
+		if prev != nil {
+			if runes.Equal(current, prev.Value.(*hisItem).Source) {
+				o.current = o.history.Back()
+				o.current.Value.(*hisItem).Clean()
+				o.historyVer++
+				return nil
+			}
+		}
+	}
+
+	if len(current) == 0 {
+		o.current = o.history.Back()
+		if o.current != nil {
+			o.current.Value.(*hisItem).Clean()
+			o.historyVer++
+			return nil
+		}
+	}
+
+	if o.current != o.history.Back() {
+		// move history item to current command
+		currentItem := o.current.Value.(*hisItem)
+		// set current to last item
+		o.current = o.history.Back()
+
+		current = runes.Copy(currentItem.Tmp)
+	}
+
+	// err only can be a IO error, just report
+	err = o.Update(current, true)
+
+	// push a new one to commit current command
+	o.historyVer++
+	o.Push(nil)
+	return
+}
+
+func (o *opHistory) Revert() {
+	o.historyVer++
+	o.current = o.history.Back()
+}
+
+func (o *opHistory) Update(s []rune, commit bool) (err error) {
+	if !o.isEnabled() {
+		return nil
+	}
+
+	o.fdLock.Lock()
+	defer o.fdLock.Unlock()
+	s = runes.Copy(s)
+	if o.current == nil {
+		o.Push(s)
+		o.Compact()
+		return
+	}
+	r := o.current.Value.(*hisItem)
+	r.Version = o.historyVer
+	if commit {
+		r.Source = s
+		if o.fd != nil {
+			// just report the error
+			_, err = o.fd.Write([]byte(string(r.Source) + "\n"))
+		}
+	} else {
+		r.Tmp = append(r.Tmp[:0], s...)
+	}
+	o.current.Value = r
+	o.Compact()
+	return
+}
+
+func (o *opHistory) Push(s []rune) {
+	s = runes.Copy(s)
+	elem := o.history.PushBack(&hisItem{Source: s})
+	o.current = elem
+}

vendor/github.com/ergochat/readline/internal/ansi/ansi.go

@@ -0,0 +1,7 @@
+//go:build !windows
+
+package ansi
+
+func EnableANSI() error {
+	return nil
+}

vendor/github.com/ergochat/readline/internal/ansi/ansi_windows.go

@@ -0,0 +1,85 @@
+//go:build windows
+
+/*
+Copyright (c) Jason Walton <dev@lucid.thedremaing.org> (https://www.thedreaming.org)
+Copyright (c) Sindre Sorhus <sindresorhus@gmail.com> (https://sindresorhus.com)
+
+Released under the MIT License:
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+*/
+
+package ansi
+
+import (
+	"sync"
+
+	"golang.org/x/sys/windows"
+)
+
+var (
+	ansiErr  error
+	ansiOnce sync.Once
+)
+
+func EnableANSI() error {
+	ansiOnce.Do(func() {
+		ansiErr = realEnableANSI()
+	})
+	return ansiErr
+}
+
+func realEnableANSI() error {
+	// We want to enable the following modes, if they are not already set:
+	// ENABLE_VIRTUAL_TERMINAL_PROCESSING on stdout (color support)
+	// ENABLE_VIRTUAL_TERMINAL_INPUT on stdin (ansi input sequences)
+	// See https://docs.microsoft.com/en-us/windows/console/console-virtual-terminal-sequences
+	if err := windowsSetMode(windows.STD_OUTPUT_HANDLE, windows.ENABLE_VIRTUAL_TERMINAL_PROCESSING); err != nil {
+		return err
+	}
+	if err := windowsSetMode(windows.STD_INPUT_HANDLE, windows.ENABLE_VIRTUAL_TERMINAL_INPUT); err != nil {
+		return err
+	}
+	return nil
+}
+
+func windowsSetMode(stdhandle uint32, modeFlag uint32) (err error) {
+	handle, err := windows.GetStdHandle(stdhandle)
+	if err != nil {
+		return err
+	}
+
+	// Get the existing console mode.
+	var mode uint32
+	err = windows.GetConsoleMode(handle, &mode)
+	if err != nil {
+		return err
+	}
+
+	// Enable the mode if it is not currently set
+	if mode&modeFlag != modeFlag {
+		mode = mode | modeFlag
+		err = windows.SetConsoleMode(handle, mode)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}

vendor/github.com/ergochat/readline/internal/platform/utils_unix.go

@@ -0,0 +1,83 @@
+//go:build aix || darwin || dragonfly || freebsd || (linux && !appengine) || netbsd || openbsd || os400 || solaris || zos
+
+package platform
+
+import (
+	"context"
+	"os"
+	"os/signal"
+	"sync"
+	"syscall"
+
+	"github.com/ergochat/readline/internal/term"
+)
+
+const (
+	IsWindows = false
+)
+
+// SuspendProcess suspends the process with SIGTSTP,
+// then blocks until it is resumed.
+func SuspendProcess() {
+	ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGCONT)
+	defer stop()
+
+	p, err := os.FindProcess(os.Getpid())
+	if err != nil {
+		panic(err)
+	}
+	p.Signal(syscall.SIGTSTP)
+	// wait for SIGCONT
+	<-ctx.Done()
+}
+
+// getWidthHeight of the terminal using given file descriptor
+func getWidthHeight(stdoutFd int) (width int, height int) {
+	width, height, err := term.GetSize(stdoutFd)
+	if err != nil {
+		return -1, -1
+	}
+	return
+}
+
+// GetScreenSize returns the width/height of the terminal or -1,-1 or error
+func GetScreenSize() (width int, height int) {
+	width, height = getWidthHeight(syscall.Stdout)
+	if width < 0 {
+		width, height = getWidthHeight(syscall.Stderr)
+	}
+	return
+}
+
+func DefaultIsTerminal() bool {
+	return term.IsTerminal(syscall.Stdin) && (term.IsTerminal(syscall.Stdout) || term.IsTerminal(syscall.Stderr))
+}
+
+// -----------------------------------------------------------------------------
+
+var (
+	sizeChange         sync.Once
+	sizeChangeCallback func()
+)
+
+func DefaultOnWidthChanged(f func()) {
+	DefaultOnSizeChanged(f)
+}
+
+func DefaultOnSizeChanged(f func()) {
+	sizeChangeCallback = f
+	sizeChange.Do(func() {
+		ch := make(chan os.Signal, 1)
+		signal.Notify(ch, syscall.SIGWINCH)
+
+		go func() {
+			for {
+				_, ok := <-ch
+				if !ok {
+					break
+				}
+				sizeChangeCallback()
+			}
+		}()
+	})
+}

vendor/github.com/ergochat/readline/internal/platform/utils_windows.go

@@ -0,0 +1,38 @@
+//go:build windows
+
+package platform
+
+import (
+	"syscall"
+
+	"github.com/ergochat/readline/internal/term"
+)
+
+const (
+	IsWindows = true
+)
+
+func SuspendProcess() {
+}
+
+// GetScreenSize returns the width, height of the terminal or -1,-1
+func GetScreenSize() (width int, height int) {
+	width, height, err := term.GetSize(int(syscall.Stdout))
+	if err == nil {
+		return width, height
+	} else {
+		return 0, 0
+	}
+}
+
+func DefaultIsTerminal() bool {
+	return term.IsTerminal(int(syscall.Stdin)) && term.IsTerminal(int(syscall.Stdout))
+}
+
+func DefaultOnWidthChanged(f func()) {
+	DefaultOnSizeChanged(f)
+}
+
+func DefaultOnSizeChanged(f func()) {
+	// TODO: does Windows have a SIGWINCH analogue?
+}

vendor/github.com/ergochat/readline/internal/ringbuf/ringbuf.go

@@ -0,0 +1,222 @@
+// Copyright (c) 2023 Shivaram Lingamneni <slingamn@cs.stanford.edu>
+// released under the MIT license
+
+package ringbuf
+
+type Buffer[T any] struct {
+	// three possible states:
+	// empty: start == end == -1
+	// partially full: start != end
+	// full: start == end > 0
+	// if entries exist, they go from `start` to `(end - 1) % length`
+	buffer      []T
+	start       int
+	end         int
+	maximumSize int
+}
+
+func NewExpandableBuffer[T any](initialSize, maximumSize int) (result *Buffer[T]) {
+	result = new(Buffer[T])
+	result.Initialize(initialSize, maximumSize)
+	return
+}
+
+func (hist *Buffer[T]) Initialize(initialSize, maximumSize int) {
+	if maximumSize == 0 {
+		panic("maximum size cannot be 0")
+	}
+	hist.buffer = make([]T, initialSize)
+	hist.start = -1
+	hist.end = -1
+	hist.maximumSize = maximumSize
+}
+
+// Add adds an item to the buffer
+func (list *Buffer[T]) Add(item T) {
+	list.maybeExpand()
+
+	var pos int
+	if list.start == -1 { // empty
+		pos = 0
+		list.start = 0
+		list.end = 1 % len(list.buffer)
+	} else if list.start != list.end { // partially full
+		pos = list.end
+		list.end = (list.end + 1) % len(list.buffer)
+	} else if list.start == list.end { // full
+		pos = list.end
+		list.end = (list.end + 1) % len(list.buffer)
+		list.start = list.end // advance start as well, overwriting first entry
+	}
+
+	list.buffer[pos] = item
+}
+
+func (list *Buffer[T]) Pop() (item T, success bool) {
+	length := list.Length()
+	if length == 0 {
+		return item, false
+	} else {
+		pos := list.prev(list.end)
+		item = list.buffer[pos]
+		list.buffer[pos] = *new(T) // TODO verify that this doesn't allocate
+		if length > 1 {
+			list.end = pos
+		} else {
+			// reset to empty buffer
+			list.start = -1
+			list.end = -1
+		}
+		return item, true
+	}
+}
+
+func (list *Buffer[T]) Range(ascending bool, rangeFunction func(item *T) (stopIteration bool)) {
+	if list.start == -1 || len(list.buffer) == 0 {
+		return
+	}
+
+	var pos, stop int
+	if ascending {
+		pos = list.start
+		stop = list.prev(list.end)
+	} else {
+		pos = list.prev(list.end)
+		stop = list.start
+	}
+
+	for {
+		if shouldStop := rangeFunction(&list.buffer[pos]); shouldStop {
+			return
+		}
+
+		if pos == stop {
+			return
+		}
+
+		if ascending {
+			pos = list.next(pos)
+		} else {
+			pos = list.prev(pos)
+		}
+	}
+}
+
+type Predicate[T any] func(item *T) (matches bool)
+
+func (list *Buffer[T]) Match(ascending bool, predicate Predicate[T], limit int) []T {
+	var results []T
+	rangeFunc := func(item *T) (stopIteration bool) {
+		if predicate(item) {
+			results = append(results, *item)
+			return limit > 0 && len(results) >= limit
+		} else {
+			return false
+		}
+	}
+	list.Range(ascending, rangeFunc)
+	return results
+}
+
+func (list *Buffer[T]) prev(index int) int {
+	switch index {
+	case 0:
+		return len(list.buffer) - 1
+	default:
+		return index - 1
+	}
+}
+
+func (list *Buffer[T]) next(index int) int {
+	switch index {
+	case len(list.buffer) - 1:
+		return 0
+	default:
+		return index + 1
+	}
+}
+
+func (list *Buffer[T]) maybeExpand() {
+	length := list.Length()
+	if length < len(list.buffer) {
+		return // we have spare capacity already
+	}
+
+	if len(list.buffer) == list.maximumSize {
+		return // cannot expand any further
+	}
+
+	newSize := roundUpToPowerOfTwo(length + 1)
+	if list.maximumSize < newSize {
+		newSize = list.maximumSize
+	}
+	list.resize(newSize)
+}
+
+// return n such that v <= n and n == 2**i for some i
+func roundUpToPowerOfTwo(v int) int {
+	// http://graphics.stanford.edu/~seander/bithacks.html
+	v -= 1
+	v |= v >> 1
+	v |= v >> 2
+	v |= v >> 4
+	v |= v >> 8
+	v |= v >> 16
+	return v + 1
+}
+
+func (hist *Buffer[T]) Length() int {
+	if hist.start == -1 {
+		return 0
+	} else if hist.start < hist.end {
+		return hist.end - hist.start
+	} else {
+		return len(hist.buffer) - (hist.start - hist.end)
+	}
+}
+
+func (list *Buffer[T]) resize(size int) {
+	newbuffer := make([]T, size)
+
+	if list.start == -1 {
+		// indices are already correct and nothing needs to be copied
+	} else if size == 0 {
+		// this is now the empty list
+		list.start = -1
+		list.end = -1
+	} else {
+		currentLength := list.Length()
+		start := list.start
+		end := list.end
+		// if we're truncating, keep the latest entries, not the earliest
+		if size < currentLength {
+			start = list.end - size
+			if start < 0 {
+				start += len(list.buffer)
+			}
+		}
+		if start < end {
+			copied := copy(newbuffer, list.buffer[start:end])
+			list.start = 0
+			list.end = copied % size
+		} else {
+			lenInitial := len(list.buffer) - start
+			copied := copy(newbuffer, list.buffer[start:])
+			copied += copy(newbuffer[lenInitial:], list.buffer[:end])
+			list.start = 0
+			list.end = copied % size
+		}
+	}
+
+	list.buffer = newbuffer
+}
+
+func (hist *Buffer[T]) Clear() {
+	hist.Range(true, func(item *T) bool {
+		var zero T
+		*item = zero
+		return false
+	})
+	hist.start = -1
+	hist.end = -1
+}

vendor/github.com/ergochat/readline/internal/runes/runes.go

@@ -0,0 +1,264 @@
+package runes
+
+import (
+	"bytes"
+	"golang.org/x/text/width"
+	"unicode"
+	"unicode/utf8"
+)
+
+var TabWidth = 4
+
+func EqualRune(a, b rune, fold bool) bool {
+	if a == b {
+		return true
+	}
+	if !fold {
+		return false
+	}
+	if a > b {
+		a, b = b, a
+	}
+	if b < utf8.RuneSelf && 'A' <= a && a <= 'Z' {
+		if b == a+'a'-'A' {
+			return true
+		}
+	}
+	return false
+}
+
+func EqualRuneFold(a, b rune) bool {
+	return EqualRune(a, b, true)
+}
+
+func EqualFold(a, b []rune) bool {
+	if len(a) != len(b) {
+		return false
+	}
+	for i := 0; i < len(a); i++ {
+		if EqualRuneFold(a[i], b[i]) {
+			continue
+		}
+		return false
+	}
+
+	return true
+}
+
+func Equal(a, b []rune) bool {
+	if len(a) != len(b) {
+		return false
+	}
+	for i := 0; i < len(a); i++ {
+		if a[i] != b[i] {
+			return false
+		}
+	}
+	return true
+}
+
+func IndexAllBckEx(r, sub []rune, fold bool) int {
+	for i := len(r) - len(sub); i >= 0; i-- {
+		found := true
+		for j := 0; j < len(sub); j++ {
+			if !EqualRune(r[i+j], sub[j], fold) {
+				found = false
+				break
+			}
+		}
+		if found {
+			return i
+		}
+	}
+	return -1
+}
+
+// Search in runes from end to front
+func IndexAllBck(r, sub []rune) int {
+	return IndexAllBckEx(r, sub, false)
+}
+
+// Search in runes from front to end
+func IndexAll(r, sub []rune) int {
+	return IndexAllEx(r, sub, false)
+}
+
+func IndexAllEx(r, sub []rune, fold bool) int {
+	for i := 0; i < len(r); i++ {
+		found := true
+		if len(r[i:]) < len(sub) {
+			return -1
+		}
+		for j := 0; j < len(sub); j++ {
+			if !EqualRune(r[i+j], sub[j], fold) {
+				found = false
+				break
+			}
+		}
+		if found {
+			return i
+		}
+	}
+	return -1
+}
+
+func Index(r rune, rs []rune) int {
+	for i := 0; i < len(rs); i++ {
+		if rs[i] == r {
+			return i
+		}
+	}
+	return -1
+}
+
+func ColorFilter(r []rune) []rune {
+	newr := make([]rune, 0, len(r))
+	for pos := 0; pos < len(r); pos++ {
+		if r[pos] == '\033' && r[pos+1] == '[' {
+			idx := Index('m', r[pos+2:])
+			if idx == -1 {
+				continue
+			}
+			pos += idx + 2
+			continue
+		}
+		newr = append(newr, r[pos])
+	}
+	return newr
+}
+
+var zeroWidth = []*unicode.RangeTable{
+	unicode.Mn,
+	unicode.Me,
+	unicode.Cc,
+	unicode.Cf,
+}
+
+var doubleWidth = []*unicode.RangeTable{
+	unicode.Han,
+	unicode.Hangul,
+	unicode.Hiragana,
+	unicode.Katakana,
+}
+
+func Width(r rune) int {
+	if r == '\t' {
+		return TabWidth
+	}
+	if unicode.IsOneOf(zeroWidth, r) {
+		return 0
+	}
+	switch width.LookupRune(r).Kind() {
+	case width.EastAsianWide, width.EastAsianFullwidth:
+		return 2
+	default:
+		return 1
+	}
+}
+
+func WidthAll(r []rune) (length int) {
+	for i := 0; i < len(r); i++ {
+		length += Width(r[i])
+	}
+	return
+}
+
+func Backspace(r []rune) []byte {
+	return bytes.Repeat([]byte{'\b'}, WidthAll(r))
+}
+
+func Copy(r []rune) []rune {
+	n := make([]rune, len(r))
+	copy(n, r)
+	return n
+}
+
+func HasPrefixFold(r, prefix []rune) bool {
+	if len(r) < len(prefix) {
+		return false
+	}
+	return EqualFold(r[:len(prefix)], prefix)
+}
+
+func HasPrefix(r, prefix []rune) bool {
+	if len(r) < len(prefix) {
+		return false
+	}
+	return Equal(r[:len(prefix)], prefix)
+}
+
+func Aggregate(candicate [][]rune) (same []rune, size int) {
+	for i := 0; i < len(candicate[0]); i++ {
+		for j := 0; j < len(candicate)-1; j++ {
+			if i >= len(candicate[j]) || i >= len(candicate[j+1]) {
+				goto aggregate
+			}
+			if candicate[j][i] != candicate[j+1][i] {
+				goto aggregate
+			}
+		}
+		size = i + 1
+	}
+aggregate:
+	if size > 0 {
+		same = Copy(candicate[0][:size])
+		for i := 0; i < len(candicate); i++ {
+			n := Copy(candicate[i])
+			copy(n, n[size:])
+			candicate[i] = n[:len(n)-size]
+		}
+	}
+	return
+}
+
+func TrimSpaceLeft(in []rune) []rune {
+	firstIndex := len(in)
+	for i, r := range in {
+		if unicode.IsSpace(r) == false {
+			firstIndex = i
+			break
+		}
+	}
+	return in[firstIndex:]
+}
+
+func IsWordBreak(i rune) bool {
+	switch {
+	case i >= 'a' && i <= 'z':
+	case i >= 'A' && i <= 'Z':
+	case i >= '0' && i <= '9':
+	default:
+		return true
+	}
+	return false
+}
+
+// split prompt + runes into lines by screenwidth starting from an offset.
+// the prompt should be filtered before passing to only its display runes.
+// if you know the width of the next character, pass it in as it is used
+// to decide if we generate an extra empty rune array to show next is new
+// line.
+func SplitByLine(prompt, rs []rune, offset, screenWidth, nextWidth int) [][]rune {
+	ret := make([][]rune, 0)
+	prs := append(prompt, rs...)
+	si := 0
+	currentWidth := offset
+	for i, r := range prs {
+		w := Width(r)
+		if r == '\n' {
+			ret = append(ret, prs[si:i+1])
+			si = i + 1
+			currentWidth = 0
+		} else if currentWidth+w > screenWidth {
+			ret = append(ret, prs[si:i])
+			si = i
+			currentWidth = 0
+		}
+		currentWidth += w
+	}
+	ret = append(ret, prs[si:])
+	if currentWidth+nextWidth > screenWidth {
+		ret = append(ret, []rune{})
+	}
+	return ret
+}

vendor/github.com/ergochat/readline/internal/term/term.go

@@ -0,0 +1,60 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package term provides support functions for dealing with terminals, as
+// commonly found on UNIX systems.
+//
+// Putting a terminal into raw mode is the most common requirement:
+//
+//	oldState, err := term.MakeRaw(int(os.Stdin.Fd()))
+//	if err != nil {
+//	        panic(err)
+//	}
+//	defer term.Restore(int(os.Stdin.Fd()), oldState)
+//
+// Note that on non-Unix systems os.Stdin.Fd() may not be 0.
+package term
+
+// State contains the state of a terminal.
+type State struct {
+	state
+}
+
+// IsTerminal returns whether the given file descriptor is a terminal.
+func IsTerminal(fd int) bool {
+	return isTerminal(fd)
+}
+
+// MakeRaw puts the terminal connected to the given file descriptor into raw
+// mode and returns the previous state of the terminal so that it can be
+// restored.
+func MakeRaw(fd int) (*State, error) {
+	return makeRaw(fd)
+}
+
+// GetState returns the current state of a terminal which may be useful to
+// restore the terminal after a signal.
+func GetState(fd int) (*State, error) {
+	return getState(fd)
+}
+
+// Restore restores the terminal connected to the given file descriptor to a
+// previous state.
+func Restore(fd int, oldState *State) error {
+	return restore(fd, oldState)
+}
+
+// GetSize returns the visible dimensions of the given terminal.
+//
+// These dimensions don't include any scrollback buffer height.
+func GetSize(fd int) (width, height int, err error) {
+	return getSize(fd)
+}
+
+// ReadPassword reads a line of input from a terminal without local echo.  This
+// is commonly used for inputting passwords and other sensitive data. The slice
+// returned does not include the \n.
+func ReadPassword(fd int) ([]byte, error) {
+	return readPassword(fd)
+}

vendor/github.com/ergochat/readline/internal/term/term_plan9.go

@@ -0,0 +1,42 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package term
+
+import (
+	"fmt"
+	"runtime"
+
+	"golang.org/x/sys/plan9"
+)
+
+type state struct{}
+
+func isTerminal(fd int) bool {
+	path, err := plan9.Fd2path(fd)
+	if err != nil {
+		return false
+	}
+	return path == "/dev/cons" || path == "/mnt/term/dev/cons"
+}
+
+func makeRaw(fd int) (*State, error) {
+	return nil, fmt.Errorf("terminal: MakeRaw not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
+
+func getState(fd int) (*State, error) {
+	return nil, fmt.Errorf("terminal: GetState not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
+
+func restore(fd int, state *State) error {
+	return fmt.Errorf("terminal: Restore not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
+
+func getSize(fd int) (width, height int, err error) {
+	return 0, 0, fmt.Errorf("terminal: GetSize not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
+
+func readPassword(fd int) ([]byte, error) {
+	return nil, fmt.Errorf("terminal: ReadPassword not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}

vendor/github.com/ergochat/readline/internal/term/term_unix.go

@@ -0,0 +1,91 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris || zos
+
+package term
+
+import (
+	"golang.org/x/sys/unix"
+)
+
+type state struct {
+	termios unix.Termios
+}
+
+func isTerminal(fd int) bool {
+	_, err := unix.IoctlGetTermios(fd, ioctlReadTermios)
+	return err == nil
+}
+
+func makeRaw(fd int) (*State, error) {
+	termios, err := unix.IoctlGetTermios(fd, ioctlReadTermios)
+	if err != nil {
+		return nil, err
+	}
+
+	oldState := State{state{termios: *termios}}
+
+	// This attempts to replicate the behaviour documented for cfmakeraw in
+	// the termios(3) manpage.
+	termios.Iflag &^= unix.IGNBRK | unix.BRKINT | unix.PARMRK | unix.ISTRIP | unix.INLCR | unix.IGNCR | unix.ICRNL | unix.IXON
+	//termios.Oflag &^= unix.OPOST
+	termios.Lflag &^= unix.ECHO | unix.ECHONL | unix.ICANON | unix.ISIG | unix.IEXTEN
+	termios.Cflag &^= unix.CSIZE | unix.PARENB
+	termios.Cflag |= unix.CS8
+	termios.Cc[unix.VMIN] = 1
+	termios.Cc[unix.VTIME] = 0
+	if err := unix.IoctlSetTermios(fd, ioctlWriteTermios, termios); err != nil {
+		return nil, err
+	}
+
+	return &oldState, nil
+}
+
+func getState(fd int) (*State, error) {
+	termios, err := unix.IoctlGetTermios(fd, ioctlReadTermios)
+	if err != nil {
+		return nil, err
+	}
+
+	return &State{state{termios: *termios}}, nil
+}
+
+func restore(fd int, state *State) error {
+	return unix.IoctlSetTermios(fd, ioctlWriteTermios, &state.termios)
+}
+
+func getSize(fd int) (width, height int, err error) {
+	ws, err := unix.IoctlGetWinsize(fd, unix.TIOCGWINSZ)
+	if err != nil {
+		return 0, 0, err
+	}
+	return int(ws.Col), int(ws.Row), nil
+}
+
+// passwordReader is an io.Reader that reads from a specific file descriptor.
+type passwordReader int
+
+func (r passwordReader) Read(buf []byte) (int, error) {
+	return unix.Read(int(r), buf)
+}
+
+func readPassword(fd int) ([]byte, error) {
+	termios, err := unix.IoctlGetTermios(fd, ioctlReadTermios)
+	if err != nil {
+		return nil, err
+	}
+
+	newState := *termios
+	newState.Lflag &^= unix.ECHO
+	newState.Lflag |= unix.ICANON | unix.ISIG
+	newState.Iflag |= unix.ICRNL
+	if err := unix.IoctlSetTermios(fd, ioctlWriteTermios, &newState); err != nil {
+		return nil, err
+	}
+
+	defer unix.IoctlSetTermios(fd, ioctlWriteTermios, termios)
+
+	return readPasswordLine(passwordReader(fd))
+}

vendor/github.com/ergochat/readline/internal/term/term_unix_bsd.go

@@ -0,0 +1,12 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build darwin || dragonfly || freebsd || netbsd || openbsd
+
+package term
+
+import "golang.org/x/sys/unix"
+
+const ioctlReadTermios = unix.TIOCGETA
+const ioctlWriteTermios = unix.TIOCSETA

vendor/github.com/ergochat/readline/internal/term/term_unix_other.go

@@ -0,0 +1,12 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build aix || linux || solaris || zos
+
+package term
+
+import "golang.org/x/sys/unix"
+
+const ioctlReadTermios = unix.TCGETS
+const ioctlWriteTermios = unix.TCSETS

vendor/github.com/ergochat/readline/internal/term/term_unsupported.go

@@ -0,0 +1,38 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !aix && !darwin && !dragonfly && !freebsd && !linux && !netbsd && !openbsd && !zos && !windows && !solaris && !plan9
+
+package term
+
+import (
+	"fmt"
+	"runtime"
+)
+
+type state struct{}
+
+func isTerminal(fd int) bool {
+	return false
+}
+
+func makeRaw(fd int) (*State, error) {
+	return nil, fmt.Errorf("terminal: MakeRaw not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
+
+func getState(fd int) (*State, error) {
+	return nil, fmt.Errorf("terminal: GetState not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
+
+func restore(fd int, state *State) error {
+	return fmt.Errorf("terminal: Restore not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
+
+func getSize(fd int) (width, height int, err error) {
+	return 0, 0, fmt.Errorf("terminal: GetSize not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
+
+func readPassword(fd int) ([]byte, error) {
+	return nil, fmt.Errorf("terminal: ReadPassword not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}

vendor/github.com/ergochat/readline/internal/term/term_windows.go

@@ -0,0 +1,79 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package term
+
+import (
+	"os"
+
+	"golang.org/x/sys/windows"
+)
+
+type state struct {
+	mode uint32
+}
+
+func isTerminal(fd int) bool {
+	var st uint32
+	err := windows.GetConsoleMode(windows.Handle(fd), &st)
+	return err == nil
+}
+
+func makeRaw(fd int) (*State, error) {
+	var st uint32
+	if err := windows.GetConsoleMode(windows.Handle(fd), &st); err != nil {
+		return nil, err
+	}
+	raw := st &^ (windows.ENABLE_ECHO_INPUT | windows.ENABLE_PROCESSED_INPUT | windows.ENABLE_LINE_INPUT | windows.ENABLE_PROCESSED_OUTPUT)
+	if err := windows.SetConsoleMode(windows.Handle(fd), raw); err != nil {
+		return nil, err
+	}
+	return &State{state{st}}, nil
+}
+
+func getState(fd int) (*State, error) {
+	var st uint32
+	if err := windows.GetConsoleMode(windows.Handle(fd), &st); err != nil {
+		return nil, err
+	}
+	return &State{state{st}}, nil
+}
+
+func restore(fd int, state *State) error {
+	return windows.SetConsoleMode(windows.Handle(fd), state.mode)
+}
+
+func getSize(fd int) (width, height int, err error) {
+	var info windows.ConsoleScreenBufferInfo
+	if err := windows.GetConsoleScreenBufferInfo(windows.Handle(fd), &info); err != nil {
+		return 0, 0, err
+	}
+	return int(info.Window.Right - info.Window.Left + 1), int(info.Window.Bottom - info.Window.Top + 1), nil
+}
+
+func readPassword(fd int) ([]byte, error) {
+	var st uint32
+	if err := windows.GetConsoleMode(windows.Handle(fd), &st); err != nil {
+		return nil, err
+	}
+	old := st
+
+	st &^= (windows.ENABLE_ECHO_INPUT | windows.ENABLE_LINE_INPUT)
+	st |= (windows.ENABLE_PROCESSED_OUTPUT | windows.ENABLE_PROCESSED_INPUT)
+	if err := windows.SetConsoleMode(windows.Handle(fd), st); err != nil {
+		return nil, err
+	}
+
+	defer windows.SetConsoleMode(windows.Handle(fd), old)
+
+	var h windows.Handle
+	p, _ := windows.GetCurrentProcess()
+	if err := windows.DuplicateHandle(p, windows.Handle(fd), p, &h, 0, false, windows.DUPLICATE_SAME_ACCESS); err != nil {
+		return nil, err
+	}
+
+	f := os.NewFile(uintptr(h), "stdin")
+	defer f.Close()
+	return readPasswordLine(f)
+}

vendor/github.com/ergochat/readline/internal/term/terminal.go

@@ -0,0 +1,986 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package term
+
+import (
+	"bytes"
+	"io"
+	"runtime"
+	"strconv"
+	"sync"
+	"unicode/utf8"
+)
+
+// EscapeCodes contains escape sequences that can be written to the terminal in
+// order to achieve different styles of text.
+type EscapeCodes struct {
+	// Foreground colors
+	Black, Red, Green, Yellow, Blue, Magenta, Cyan, White []byte
+
+	// Reset all attributes
+	Reset []byte
+}
+
+var vt100EscapeCodes = EscapeCodes{
+	Black:   []byte{keyEscape, '[', '3', '0', 'm'},
+	Red:     []byte{keyEscape, '[', '3', '1', 'm'},
+	Green:   []byte{keyEscape, '[', '3', '2', 'm'},
+	Yellow:  []byte{keyEscape, '[', '3', '3', 'm'},
+	Blue:    []byte{keyEscape, '[', '3', '4', 'm'},
+	Magenta: []byte{keyEscape, '[', '3', '5', 'm'},
+	Cyan:    []byte{keyEscape, '[', '3', '6', 'm'},
+	White:   []byte{keyEscape, '[', '3', '7', 'm'},
+
+	Reset: []byte{keyEscape, '[', '0', 'm'},
+}
+
+// Terminal contains the state for running a VT100 terminal that is capable of
+// reading lines of input.
+type Terminal struct {
+	// AutoCompleteCallback, if non-null, is called for each keypress with
+	// the full input line and the current position of the cursor (in
+	// bytes, as an index into |line|). If it returns ok=false, the key
+	// press is processed normally. Otherwise it returns a replacement line
+	// and the new cursor position.
+	AutoCompleteCallback func(line string, pos int, key rune) (newLine string, newPos int, ok bool)
+
+	// Escape contains a pointer to the escape codes for this terminal.
+	// It's always a valid pointer, although the escape codes themselves
+	// may be empty if the terminal doesn't support them.
+	Escape *EscapeCodes
+
+	// lock protects the terminal and the state in this object from
+	// concurrent processing of a key press and a Write() call.
+	lock sync.Mutex
+
+	c      io.ReadWriter
+	prompt []rune
+
+	// line is the current line being entered.
+	line []rune
+	// pos is the logical position of the cursor in line
+	pos int
+	// echo is true if local echo is enabled
+	echo bool
+	// pasteActive is true iff there is a bracketed paste operation in
+	// progress.
+	pasteActive bool
+
+	// cursorX contains the current X value of the cursor where the left
+	// edge is 0. cursorY contains the row number where the first row of
+	// the current line is 0.
+	cursorX, cursorY int
+	// maxLine is the greatest value of cursorY so far.
+	maxLine int
+
+	termWidth, termHeight int
+
+	// outBuf contains the terminal data to be sent.
+	outBuf []byte
+	// remainder contains the remainder of any partial key sequences after
+	// a read. It aliases into inBuf.
+	remainder []byte
+	inBuf     [256]byte
+
+	// history contains previously entered commands so that they can be
+	// accessed with the up and down keys.
+	history stRingBuffer
+	// historyIndex stores the currently accessed history entry, where zero
+	// means the immediately previous entry.
+	historyIndex int
+	// When navigating up and down the history it's possible to return to
+	// the incomplete, initial line. That value is stored in
+	// historyPending.
+	historyPending string
+}
+
+// NewTerminal runs a VT100 terminal on the given ReadWriter. If the ReadWriter is
+// a local terminal, that terminal must first have been put into raw mode.
+// prompt is a string that is written at the start of each input line (i.e.
+// "> ").
+func NewTerminal(c io.ReadWriter, prompt string) *Terminal {
+	return &Terminal{
+		Escape:       &vt100EscapeCodes,
+		c:            c,
+		prompt:       []rune(prompt),
+		termWidth:    80,
+		termHeight:   24,
+		echo:         true,
+		historyIndex: -1,
+	}
+}
+
+const (
+	keyCtrlC     = 3
+	keyCtrlD     = 4
+	keyCtrlU     = 21
+	keyEnter     = '\r'
+	keyEscape    = 27
+	keyBackspace = 127
+	keyUnknown   = 0xd800 /* UTF-16 surrogate area */ + iota
+	keyUp
+	keyDown
+	keyLeft
+	keyRight
+	keyAltLeft
+	keyAltRight
+	keyHome
+	keyEnd
+	keyDeleteWord
+	keyDeleteLine
+	keyClearScreen
+	keyPasteStart
+	keyPasteEnd
+)
+
+var (
+	crlf       = []byte{'\r', '\n'}
+	pasteStart = []byte{keyEscape, '[', '2', '0', '0', '~'}
+	pasteEnd   = []byte{keyEscape, '[', '2', '0', '1', '~'}
+)
+
+// bytesToKey tries to parse a key sequence from b. If successful, it returns
+// the key and the remainder of the input. Otherwise it returns utf8.RuneError.
+func bytesToKey(b []byte, pasteActive bool) (rune, []byte) {
+	if len(b) == 0 {
+		return utf8.RuneError, nil
+	}
+
+	if !pasteActive {
+		switch b[0] {
+		case 1: // ^A
+			return keyHome, b[1:]
+		case 2: // ^B
+			return keyLeft, b[1:]
+		case 5: // ^E
+			return keyEnd, b[1:]
+		case 6: // ^F
+			return keyRight, b[1:]
+		case 8: // ^H
+			return keyBackspace, b[1:]
+		case 11: // ^K
+			return keyDeleteLine, b[1:]
+		case 12: // ^L
+			return keyClearScreen, b[1:]
+		case 23: // ^W
+			return keyDeleteWord, b[1:]
+		case 14: // ^N
+			return keyDown, b[1:]
+		case 16: // ^P
+			return keyUp, b[1:]
+		}
+	}
+
+	if b[0] != keyEscape {
+		if !utf8.FullRune(b) {
+			return utf8.RuneError, b
+		}
+		r, l := utf8.DecodeRune(b)
+		return r, b[l:]
+	}
+
+	if !pasteActive && len(b) >= 3 && b[0] == keyEscape && b[1] == '[' {
+		switch b[2] {
+		case 'A':
+			return keyUp, b[3:]
+		case 'B':
+			return keyDown, b[3:]
+		case 'C':
+			return keyRight, b[3:]
+		case 'D':
+			return keyLeft, b[3:]
+		case 'H':
+			return keyHome, b[3:]
+		case 'F':
+			return keyEnd, b[3:]
+		}
+	}
+
+	if !pasteActive && len(b) >= 6 && b[0] == keyEscape && b[1] == '[' && b[2] == '1' && b[3] == ';' && b[4] == '3' {
+		switch b[5] {
+		case 'C':
+			return keyAltRight, b[6:]
+		case 'D':
+			return keyAltLeft, b[6:]
+		}
+	}
+
+	if !pasteActive && len(b) >= 6 && bytes.Equal(b[:6], pasteStart) {
+		return keyPasteStart, b[6:]
+	}
+
+	if pasteActive && len(b) >= 6 && bytes.Equal(b[:6], pasteEnd) {
+		return keyPasteEnd, b[6:]
+	}
+
+	// If we get here then we have a key that we don't recognise, or a
+	// partial sequence. It's not clear how one should find the end of a
+	// sequence without knowing them all, but it seems that [a-zA-Z~] only
+	// appears at the end of a sequence.
+	for i, c := range b[0:] {
+		if c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z' || c == '~' {
+			return keyUnknown, b[i+1:]
+		}
+	}
+
+	return utf8.RuneError, b
+}
+
+// queue appends data to the end of t.outBuf
+func (t *Terminal) queue(data []rune) {
+	t.outBuf = append(t.outBuf, []byte(string(data))...)
+}
+
+var space = []rune{' '}
+
+func isPrintable(key rune) bool {
+	isInSurrogateArea := key >= 0xd800 && key <= 0xdbff
+	return key >= 32 && !isInSurrogateArea
+}
+
+// moveCursorToPos appends data to t.outBuf which will move the cursor to the
+// given, logical position in the text.
+func (t *Terminal) moveCursorToPos(pos int) {
+	if !t.echo {
+		return
+	}
+
+	x := visualLength(t.prompt) + pos
+	y := x / t.termWidth
+	x = x % t.termWidth
+
+	up := 0
+	if y < t.cursorY {
+		up = t.cursorY - y
+	}
+
+	down := 0
+	if y > t.cursorY {
+		down = y - t.cursorY
+	}
+
+	left := 0
+	if x < t.cursorX {
+		left = t.cursorX - x
+	}
+
+	right := 0
+	if x > t.cursorX {
+		right = x - t.cursorX
+	}
+
+	t.cursorX = x
+	t.cursorY = y
+	t.move(up, down, left, right)
+}
+
+func (t *Terminal) move(up, down, left, right int) {
+	m := []rune{}
+
+	// 1 unit up can be expressed as ^[[A or ^[A
+	// 5 units up can be expressed as ^[[5A
+
+	if up == 1 {
+		m = append(m, keyEscape, '[', 'A')
+	} else if up > 1 {
+		m = append(m, keyEscape, '[')
+		m = append(m, []rune(strconv.Itoa(up))...)
+		m = append(m, 'A')
+	}
+
+	if down == 1 {
+		m = append(m, keyEscape, '[', 'B')
+	} else if down > 1 {
+		m = append(m, keyEscape, '[')
+		m = append(m, []rune(strconv.Itoa(down))...)
+		m = append(m, 'B')
+	}
+
+	if right == 1 {
+		m = append(m, keyEscape, '[', 'C')
+	} else if right > 1 {
+		m = append(m, keyEscape, '[')
+		m = append(m, []rune(strconv.Itoa(right))...)
+		m = append(m, 'C')
+	}
+
+	if left == 1 {
+		m = append(m, keyEscape, '[', 'D')
+	} else if left > 1 {
+		m = append(m, keyEscape, '[')
+		m = append(m, []rune(strconv.Itoa(left))...)
+		m = append(m, 'D')
+	}
+
+	t.queue(m)
+}
+
+func (t *Terminal) clearLineToRight() {
+	op := []rune{keyEscape, '[', 'K'}
+	t.queue(op)
+}
+
+const maxLineLength = 4096
+
+func (t *Terminal) setLine(newLine []rune, newPos int) {
+	if t.echo {
+		t.moveCursorToPos(0)
+		t.writeLine(newLine)
+		for i := len(newLine); i < len(t.line); i++ {
+			t.writeLine(space)
+		}
+		t.moveCursorToPos(newPos)
+	}
+	t.line = newLine
+	t.pos = newPos
+}
+
+func (t *Terminal) advanceCursor(places int) {
+	t.cursorX += places
+	t.cursorY += t.cursorX / t.termWidth
+	if t.cursorY > t.maxLine {
+		t.maxLine = t.cursorY
+	}
+	t.cursorX = t.cursorX % t.termWidth
+
+	if places > 0 && t.cursorX == 0 {
+		// Normally terminals will advance the current position
+		// when writing a character. But that doesn't happen
+		// for the last character in a line. However, when
+		// writing a character (except a new line) that causes
+		// a line wrap, the position will be advanced two
+		// places.
+		//
+		// So, if we are stopping at the end of a line, we
+		// need to write a newline so that our cursor can be
+		// advanced to the next line.
+		t.outBuf = append(t.outBuf, '\r', '\n')
+	}
+}
+
+func (t *Terminal) eraseNPreviousChars(n int) {
+	if n == 0 {
+		return
+	}
+
+	if t.pos < n {
+		n = t.pos
+	}
+	t.pos -= n
+	t.moveCursorToPos(t.pos)
+
+	copy(t.line[t.pos:], t.line[n+t.pos:])
+	t.line = t.line[:len(t.line)-n]
+	if t.echo {
+		t.writeLine(t.line[t.pos:])
+		for i := 0; i < n; i++ {
+			t.queue(space)
+		}
+		t.advanceCursor(n)
+		t.moveCursorToPos(t.pos)
+	}
+}
+
+// countToLeftWord returns then number of characters from the cursor to the
+// start of the previous word.
+func (t *Terminal) countToLeftWord() int {
+	if t.pos == 0 {
+		return 0
+	}
+
+	pos := t.pos - 1
+	for pos > 0 {
+		if t.line[pos] != ' ' {
+			break
+		}
+		pos--
+	}
+	for pos > 0 {
+		if t.line[pos] == ' ' {
+			pos++
+			break
+		}
+		pos--
+	}
+
+	return t.pos - pos
+}
+
+// countToRightWord returns then number of characters from the cursor to the
+// start of the next word.
+func (t *Terminal) countToRightWord() int {
+	pos := t.pos
+	for pos < len(t.line) {
+		if t.line[pos] == ' ' {
+			break
+		}
+		pos++
+	}
+	for pos < len(t.line) {
+		if t.line[pos] != ' ' {
+			break
+		}
+		pos++
+	}
+	return pos - t.pos
+}
+
+// visualLength returns the number of visible glyphs in s.
+func visualLength(runes []rune) int {
+	inEscapeSeq := false
+	length := 0
+
+	for _, r := range runes {
+		switch {
+		case inEscapeSeq:
+			if (r >= 'a' && r <= 'z') || (r >= 'A' && r <= 'Z') {
+				inEscapeSeq = false
+			}
+		case r == '\x1b':
+			inEscapeSeq = true
+		default:
+			length++
+		}
+	}
+
+	return length
+}
+
+// handleKey processes the given key and, optionally, returns a line of text
+// that the user has entered.
+func (t *Terminal) handleKey(key rune) (line string, ok bool) {
+	if t.pasteActive && key != keyEnter {
+		t.addKeyToLine(key)
+		return
+	}
+
+	switch key {
+	case keyBackspace:
+		if t.pos == 0 {
+			return
+		}
+		t.eraseNPreviousChars(1)
+	case keyAltLeft:
+		// move left by a word.
+		t.pos -= t.countToLeftWord()
+		t.moveCursorToPos(t.pos)
+	case keyAltRight:
+		// move right by a word.
+		t.pos += t.countToRightWord()
+		t.moveCursorToPos(t.pos)
+	case keyLeft:
+		if t.pos == 0 {
+			return
+		}
+		t.pos--
+		t.moveCursorToPos(t.pos)
+	case keyRight:
+		if t.pos == len(t.line) {
+			return
+		}
+		t.pos++
+		t.moveCursorToPos(t.pos)
+	case keyHome:
+		if t.pos == 0 {
+			return
+		}
+		t.pos = 0
+		t.moveCursorToPos(t.pos)
+	case keyEnd:
+		if t.pos == len(t.line) {
+			return
+		}
+		t.pos = len(t.line)
+		t.moveCursorToPos(t.pos)
+	case keyUp:
+		entry, ok := t.history.NthPreviousEntry(t.historyIndex + 1)
+		if !ok {
+			return "", false
+		}
+		if t.historyIndex == -1 {
+			t.historyPending = string(t.line)
+		}
+		t.historyIndex++
+		runes := []rune(entry)
+		t.setLine(runes, len(runes))
+	case keyDown:
+		switch t.historyIndex {
+		case -1:
+			return
+		case 0:
+			runes := []rune(t.historyPending)
+			t.setLine(runes, len(runes))
+			t.historyIndex--
+		default:
+			entry, ok := t.history.NthPreviousEntry(t.historyIndex - 1)
+			if ok {
+				t.historyIndex--
+				runes := []rune(entry)
+				t.setLine(runes, len(runes))
+			}
+		}
+	case keyEnter:
+		t.moveCursorToPos(len(t.line))
+		t.queue([]rune("\r\n"))
+		line = string(t.line)
+		ok = true
+		t.line = t.line[:0]
+		t.pos = 0
+		t.cursorX = 0
+		t.cursorY = 0
+		t.maxLine = 0
+	case keyDeleteWord:
+		// Delete zero or more spaces and then one or more characters.
+		t.eraseNPreviousChars(t.countToLeftWord())
+	case keyDeleteLine:
+		// Delete everything from the current cursor position to the
+		// end of line.
+		for i := t.pos; i < len(t.line); i++ {
+			t.queue(space)
+			t.advanceCursor(1)
+		}
+		t.line = t.line[:t.pos]
+		t.moveCursorToPos(t.pos)
+	case keyCtrlD:
+		// Erase the character under the current position.
+		// The EOF case when the line is empty is handled in
+		// readLine().
+		if t.pos < len(t.line) {
+			t.pos++
+			t.eraseNPreviousChars(1)
+		}
+	case keyCtrlU:
+		t.eraseNPreviousChars(t.pos)
+	case keyClearScreen:
+		// Erases the screen and moves the cursor to the home position.
+		t.queue([]rune("\x1b[2J\x1b[H"))
+		t.queue(t.prompt)
+		t.cursorX, t.cursorY = 0, 0
+		t.advanceCursor(visualLength(t.prompt))
+		t.setLine(t.line, t.pos)
+	default:
+		if t.AutoCompleteCallback != nil {
+			prefix := string(t.line[:t.pos])
+			suffix := string(t.line[t.pos:])
+
+			t.lock.Unlock()
+			newLine, newPos, completeOk := t.AutoCompleteCallback(prefix+suffix, len(prefix), key)
+			t.lock.Lock()
+
+			if completeOk {
+				t.setLine([]rune(newLine), utf8.RuneCount([]byte(newLine)[:newPos]))
+				return
+			}
+		}
+		if !isPrintable(key) {
+			return
+		}
+		if len(t.line) == maxLineLength {
+			return
+		}
+		t.addKeyToLine(key)
+	}
+	return
+}
+
+// addKeyToLine inserts the given key at the current position in the current
+// line.
+func (t *Terminal) addKeyToLine(key rune) {
+	if len(t.line) == cap(t.line) {
+		newLine := make([]rune, len(t.line), 2*(1+len(t.line)))
+		copy(newLine, t.line)
+		t.line = newLine
+	}
+	t.line = t.line[:len(t.line)+1]
+	copy(t.line[t.pos+1:], t.line[t.pos:])
+	t.line[t.pos] = key
+	if t.echo {
+		t.writeLine(t.line[t.pos:])
+	}
+	t.pos++
+	t.moveCursorToPos(t.pos)
+}
+
+func (t *Terminal) writeLine(line []rune) {
+	for len(line) != 0 {
+		remainingOnLine := t.termWidth - t.cursorX
+		todo := len(line)
+		if todo > remainingOnLine {
+			todo = remainingOnLine
+		}
+		t.queue(line[:todo])
+		t.advanceCursor(visualLength(line[:todo]))
+		line = line[todo:]
+	}
+}
+
+// writeWithCRLF writes buf to w but replaces all occurrences of \n with \r\n.
+func writeWithCRLF(w io.Writer, buf []byte) (n int, err error) {
+	for len(buf) > 0 {
+		i := bytes.IndexByte(buf, '\n')
+		todo := len(buf)
+		if i >= 0 {
+			todo = i
+		}
+
+		var nn int
+		nn, err = w.Write(buf[:todo])
+		n += nn
+		if err != nil {
+			return n, err
+		}
+		buf = buf[todo:]
+
+		if i >= 0 {
+			if _, err = w.Write(crlf); err != nil {
+				return n, err
+			}
+			n++
+			buf = buf[1:]
+		}
+	}
+
+	return n, nil
+}
+
+func (t *Terminal) Write(buf []byte) (n int, err error) {
+	t.lock.Lock()
+	defer t.lock.Unlock()
+
+	if t.cursorX == 0 && t.cursorY == 0 {
+		// This is the easy case: there's nothing on the screen that we
+		// have to move out of the way.
+		return writeWithCRLF(t.c, buf)
+	}
+
+	// We have a prompt and possibly user input on the screen. We
+	// have to clear it first.
+	t.move(0 /* up */, 0 /* down */, t.cursorX /* left */, 0 /* right */)
+	t.cursorX = 0
+	t.clearLineToRight()
+
+	for t.cursorY > 0 {
+		t.move(1 /* up */, 0, 0, 0)
+		t.cursorY--
+		t.clearLineToRight()
+	}
+
+	if _, err = t.c.Write(t.outBuf); err != nil {
+		return
+	}
+	t.outBuf = t.outBuf[:0]
+
+	if n, err = writeWithCRLF(t.c, buf); err != nil {
+		return
+	}
+
+	t.writeLine(t.prompt)
+	if t.echo {
+		t.writeLine(t.line)
+	}
+
+	t.moveCursorToPos(t.pos)
+
+	if _, err = t.c.Write(t.outBuf); err != nil {
+		return
+	}
+	t.outBuf = t.outBuf[:0]
+	return
+}
+
+// ReadPassword temporarily changes the prompt and reads a password, without
+// echo, from the terminal.
+func (t *Terminal) ReadPassword(prompt string) (line string, err error) {
+	t.lock.Lock()
+	defer t.lock.Unlock()
+
+	oldPrompt := t.prompt
+	t.prompt = []rune(prompt)
+	t.echo = false
+
+	line, err = t.readLine()
+
+	t.prompt = oldPrompt
+	t.echo = true
+
+	return
+}
+
+// ReadLine returns a line of input from the terminal.
+func (t *Terminal) ReadLine() (line string, err error) {
+	t.lock.Lock()
+	defer t.lock.Unlock()
+
+	return t.readLine()
+}
+
+func (t *Terminal) readLine() (line string, err error) {
+	// t.lock must be held at this point
+
+	if t.cursorX == 0 && t.cursorY == 0 {
+		t.writeLine(t.prompt)
+		t.c.Write(t.outBuf)
+		t.outBuf = t.outBuf[:0]
+	}
+
+	lineIsPasted := t.pasteActive
+
+	for {
+		rest := t.remainder
+		lineOk := false
+		for !lineOk {
+			var key rune
+			key, rest = bytesToKey(rest, t.pasteActive)
+			if key == utf8.RuneError {
+				break
+			}
+			if !t.pasteActive {
+				if key == keyCtrlD {
+					if len(t.line) == 0 {
+						return "", io.EOF
+					}
+				}
+				if key == keyCtrlC {
+					return "", io.EOF
+				}
+				if key == keyPasteStart {
+					t.pasteActive = true
+					if len(t.line) == 0 {
+						lineIsPasted = true
+					}
+					continue
+				}
+			} else if key == keyPasteEnd {
+				t.pasteActive = false
+				continue
+			}
+			if !t.pasteActive {
+				lineIsPasted = false
+			}
+			line, lineOk = t.handleKey(key)
+		}
+		if len(rest) > 0 {
+			n := copy(t.inBuf[:], rest)
+			t.remainder = t.inBuf[:n]
+		} else {
+			t.remainder = nil
+		}
+		t.c.Write(t.outBuf)
+		t.outBuf = t.outBuf[:0]
+		if lineOk {
+			if t.echo {
+				t.historyIndex = -1
+				t.history.Add(line)
+			}
+			if lineIsPasted {
+				err = ErrPasteIndicator
+			}
+			return
+		}
+
+		// t.remainder is a slice at the beginning of t.inBuf
+		// containing a partial key sequence
+		readBuf := t.inBuf[len(t.remainder):]
+		var n int
+
+		t.lock.Unlock()
+		n, err = t.c.Read(readBuf)
+		t.lock.Lock()
+
+		if err != nil {
+			return
+		}
+
+		t.remainder = t.inBuf[:n+len(t.remainder)]
+	}
+}
+
+// SetPrompt sets the prompt to be used when reading subsequent lines.
+func (t *Terminal) SetPrompt(prompt string) {
+	t.lock.Lock()
+	defer t.lock.Unlock()
+
+	t.prompt = []rune(prompt)
+}
+
+func (t *Terminal) clearAndRepaintLinePlusNPrevious(numPrevLines int) {
+	// Move cursor to column zero at the start of the line.
+	t.move(t.cursorY, 0, t.cursorX, 0)
+	t.cursorX, t.cursorY = 0, 0
+	t.clearLineToRight()
+	for t.cursorY < numPrevLines {
+		// Move down a line
+		t.move(0, 1, 0, 0)
+		t.cursorY++
+		t.clearLineToRight()
+	}
+	// Move back to beginning.
+	t.move(t.cursorY, 0, 0, 0)
+	t.cursorX, t.cursorY = 0, 0
+
+	t.queue(t.prompt)
+	t.advanceCursor(visualLength(t.prompt))
+	t.writeLine(t.line)
+	t.moveCursorToPos(t.pos)
+}
+
+func (t *Terminal) SetSize(width, height int) error {
+	t.lock.Lock()
+	defer t.lock.Unlock()
+
+	if width == 0 {
+		width = 1
+	}
+
+	oldWidth := t.termWidth
+	t.termWidth, t.termHeight = width, height
+
+	switch {
+	case width == oldWidth:
+		// If the width didn't change then nothing else needs to be
+		// done.
+		return nil
+	case len(t.line) == 0 && t.cursorX == 0 && t.cursorY == 0:
+		// If there is nothing on current line and no prompt printed,
+		// just do nothing
+		return nil
+	case width < oldWidth:
+		// Some terminals (e.g. xterm) will truncate lines that were
+		// too long when shinking. Others, (e.g. gnome-terminal) will
+		// attempt to wrap them. For the former, repainting t.maxLine
+		// works great, but that behaviour goes badly wrong in the case
+		// of the latter because they have doubled every full line.
+
+		// We assume that we are working on a terminal that wraps lines
+		// and adjust the cursor position based on every previous line
+		// wrapping and turning into two. This causes the prompt on
+		// xterms to move upwards, which isn't great, but it avoids a
+		// huge mess with gnome-terminal.
+		if t.cursorX >= t.termWidth {
+			t.cursorX = t.termWidth - 1
+		}
+		t.cursorY *= 2
+		t.clearAndRepaintLinePlusNPrevious(t.maxLine * 2)
+	case width > oldWidth:
+		// If the terminal expands then our position calculations will
+		// be wrong in the future because we think the cursor is
+		// |t.pos| chars into the string, but there will be a gap at
+		// the end of any wrapped line.
+		//
+		// But the position will actually be correct until we move, so
+		// we can move back to the beginning and repaint everything.
+		t.clearAndRepaintLinePlusNPrevious(t.maxLine)
+	}
+
+	_, err := t.c.Write(t.outBuf)
+	t.outBuf = t.outBuf[:0]
+	return err
+}
+
+type pasteIndicatorError struct{}
+
+func (pasteIndicatorError) Error() string {
+	return "terminal: ErrPasteIndicator not correctly handled"
+}
+
+// ErrPasteIndicator may be returned from ReadLine as the error, in addition
+// to valid line data. It indicates that bracketed paste mode is enabled and
+// that the returned line consists only of pasted data. Programs may wish to
+// interpret pasted data more literally than typed data.
+var ErrPasteIndicator = pasteIndicatorError{}
+
+// SetBracketedPasteMode requests that the terminal bracket paste operations
+// with markers. Not all terminals support this but, if it is supported, then
+// enabling this mode will stop any autocomplete callback from running due to
+// pastes. Additionally, any lines that are completely pasted will be returned
+// from ReadLine with the error set to ErrPasteIndicator.
+func (t *Terminal) SetBracketedPasteMode(on bool) {
+	if on {
+		io.WriteString(t.c, "\x1b[?2004h")
+	} else {
+		io.WriteString(t.c, "\x1b[?2004l")
+	}
+}
+
+// stRingBuffer is a ring buffer of strings.
+type stRingBuffer struct {
+	// entries contains max elements.
+	entries []string
+	max     int
+	// head contains the index of the element most recently added to the ring.
+	head int
+	// size contains the number of elements in the ring.
+	size int
+}
+
+func (s *stRingBuffer) Add(a string) {
+	if s.entries == nil {
+		const defaultNumEntries = 100
+		s.entries = make([]string, defaultNumEntries)
+		s.max = defaultNumEntries
+	}
+
+	s.head = (s.head + 1) % s.max
+	s.entries[s.head] = a
+	if s.size < s.max {
+		s.size++
+	}
+}
+
+// NthPreviousEntry returns the value passed to the nth previous call to Add.
+// If n is zero then the immediately prior value is returned, if one, then the
+// next most recent, and so on. If such an element doesn't exist then ok is
+// false.
+func (s *stRingBuffer) NthPreviousEntry(n int) (value string, ok bool) {
+	if n < 0 || n >= s.size {
+		return "", false
+	}
+	index := s.head - n
+	if index < 0 {
+		index += s.max
+	}
+	return s.entries[index], true
+}
+
+// readPasswordLine reads from reader until it finds \n or io.EOF.
+// The slice returned does not include the \n.
+// readPasswordLine also ignores any \r it finds.
+// Windows uses \r as end of line. So, on Windows, readPasswordLine
+// reads until it finds \r and ignores any \n it finds during processing.
+func readPasswordLine(reader io.Reader) ([]byte, error) {
+	var buf [1]byte
+	var ret []byte
+
+	for {
+		n, err := reader.Read(buf[:])
+		if n > 0 {
+			switch buf[0] {
+			case '\b':
+				if len(ret) > 0 {
+					ret = ret[:len(ret)-1]
+				}
+			case '\n':
+				if runtime.GOOS != "windows" {
+					return ret, nil
+				}
+				// otherwise ignore \n
+			case '\r':
+				if runtime.GOOS == "windows" {
+					return ret, nil
+				}
+				// otherwise ignore \r
+			default:
+				ret = append(ret, buf[0])
+			}
+			continue
+		}
+		if err != nil {
+			if err == io.EOF && len(ret) > 0 {
+				return ret, nil
+			}
+			return ret, err
+		}
+	}
+}

vendor/github.com/ergochat/readline/operation.go

@@ -0,0 +1,555 @@
+package readline
+
+import (
+	"errors"
+	"io"
+	"sync"
+	"sync/atomic"
+
+	"github.com/ergochat/readline/internal/platform"
+	"github.com/ergochat/readline/internal/runes"
+)
+
+var (
+	ErrInterrupt = errors.New("Interrupt")
+)
+
+type operation struct {
+	m       sync.Mutex
+	t       *terminal
+	buf     *runeBuffer
+	wrapOut atomic.Pointer[wrapWriter]
+	wrapErr atomic.Pointer[wrapWriter]
+
+	isPrompting bool // true when prompt written and waiting for input
+
+	history   *opHistory
+	search    *opSearch
+	completer *opCompleter
+	vim       *opVim
+	undo      *opUndo
+}
+
+func (o *operation) SetBuffer(what string) {
+	o.buf.SetNoRefresh([]rune(what))
+}
+
+type wrapWriter struct {
+	o      *operation
+	target io.Writer
+}
+
+func (w *wrapWriter) Write(b []byte) (int, error) {
+	return w.o.write(w.target, b)
+}
+
+func (o *operation) write(target io.Writer, b []byte) (int, error) {
+	o.m.Lock()
+	defer o.m.Unlock()
+
+	if !o.isPrompting {
+		return target.Write(b)
+	}
+
+	var (
+		n   int
+		err error
+	)
+	o.buf.Refresh(func() {
+		n, err = target.Write(b)
+		// Adjust the prompt start position by b
+		rout := runes.ColorFilter([]rune(string(b[:])))
+		tWidth, _ := o.t.GetWidthHeight()
+		sp := runes.SplitByLine(rout, []rune{}, o.buf.ppos, tWidth, 1)
+		if len(sp) > 1 {
+			o.buf.ppos = len(sp[len(sp)-1])
+		} else {
+			o.buf.ppos += len(rout)
+		}
+	})
+
+	o.search.RefreshIfNeeded()
+	if o.completer.IsInCompleteMode() {
+		o.completer.CompleteRefresh()
+	}
+	return n, err
+}
+
+func newOperation(t *terminal) *operation {
+	cfg := t.GetConfig()
+	op := &operation{
+		t:   t,
+		buf: newRuneBuffer(t),
+	}
+	op.SetConfig(cfg)
+	op.vim = newVimMode(op)
+	op.completer = newOpCompleter(op.buf.w, op)
+	cfg.FuncOnWidthChanged(t.OnSizeChange)
+	return op
+}
+
+func (o *operation) GetConfig() *Config {
+	return o.t.GetConfig()
+}
+
+func (o *operation) readline(deadline chan struct{}) ([]rune, error) {
+	isTyping := false // don't add new undo entries during normal typing
+
+	for {
+		keepInSearchMode := false
+		keepInCompleteMode := false
+		r, err := o.t.GetRune(deadline)
+
+		if cfg := o.GetConfig(); cfg.FuncFilterInputRune != nil && err == nil {
+			var process bool
+			r, process = cfg.FuncFilterInputRune(r)
+			if !process {
+				o.buf.Refresh(nil) // to refresh the line
+				continue           // ignore this rune
+			}
+		}
+
+		if err == io.EOF {
+			if o.buf.Len() == 0 {
+				o.buf.Clean()
+				return nil, io.EOF
+			} else {
+				// if stdin got io.EOF and there is something left in buffer,
+				// let's flush them by sending CharEnter.
+				// And we will got io.EOF int next loop.
+				r = CharEnter
+			}
+		} else if err != nil {
+			return nil, err
+		}
+		isUpdateHistory := true
+
+		if o.completer.IsInCompleteSelectMode() {
+			keepInCompleteMode = o.completer.HandleCompleteSelect(r)
+			if keepInCompleteMode {
+				continue
+			}
+
+			o.buf.Refresh(nil)
+			switch r {
+			case CharEnter, CharCtrlJ:
+				o.history.Update(o.buf.Runes(), false)
+				fallthrough
+			case CharInterrupt:
+				fallthrough
+			case CharBell:
+				continue
+			}
+		}
+
+		if o.vim.IsEnableVimMode() {
+			r = o.vim.HandleVim(r, func() rune {
+				r, err := o.t.GetRune(deadline)
+				if err == nil {
+					return r
+				} else {
+					return 0
+				}
+			})
+			if r == 0 {
+				continue
+			}
+		}
+
+		var result []rune
+
+		isTypingRune := false
+
+		switch r {
+		case CharBell:
+			if o.search.IsSearchMode() {
+				o.search.ExitSearchMode(true)
+				o.buf.Refresh(nil)
+			}
+			if o.completer.IsInCompleteMode() {
+				o.completer.ExitCompleteMode(true)
+				o.buf.Refresh(nil)
+			}
+		case CharBckSearch:
+			if !o.search.SearchMode(searchDirectionBackward) {
+				o.t.Bell()
+				break
+			}
+			keepInSearchMode = true
+		case CharCtrlU:
+			o.undo.add()
+			o.buf.KillFront()
+		case CharFwdSearch:
+			if !o.search.SearchMode(searchDirectionForward) {
+				o.t.Bell()
+				break
+			}
+			keepInSearchMode = true
+		case CharKill:
+			o.undo.add()
+			o.buf.Kill()
+			keepInCompleteMode = true
+		case MetaForward:
+			o.buf.MoveToNextWord()
+		case CharTranspose:
+			o.undo.add()
+			o.buf.Transpose()
+		case MetaBackward:
+			o.buf.MoveToPrevWord()
+		case MetaDelete:
+			o.undo.add()
+			o.buf.DeleteWord()
+		case CharLineStart:
+			o.buf.MoveToLineStart()
+		case CharLineEnd:
+			o.buf.MoveToLineEnd()
+		case CharBackspace, CharCtrlH:
+			o.undo.add()
+			if o.search.IsSearchMode() {
+				o.search.SearchBackspace()
+				keepInSearchMode = true
+				break
+			}
+
+			if o.buf.Len() == 0 {
+				o.t.Bell()
+				break
+			}
+			o.buf.Backspace()
+		case CharCtrlZ:
+			if !platform.IsWindows {
+				o.buf.Clean()
+				o.t.SleepToResume()
+				o.Refresh()
+			}
+		case CharCtrlL:
+			clearScreen(o.t)
+			o.buf.SetOffset(cursorPosition{1, 1})
+			o.Refresh()
+		case MetaBackspace, CharCtrlW:
+			o.undo.add()
+			o.buf.BackEscapeWord()
+		case MetaShiftTab:
+			// no-op
+		case CharCtrlY:
+			o.buf.Yank()
+		case CharCtrl_:
+			o.undo.undo()
+		case CharEnter, CharCtrlJ:
+			if o.search.IsSearchMode() {
+				o.search.ExitSearchMode(false)
+			}
+			if o.completer.IsInCompleteMode() {
+				o.completer.ExitCompleteMode(true)
+				o.buf.Refresh(nil)
+			}
+			o.buf.MoveToLineEnd()
+			var data []rune
+			o.buf.WriteRune('\n')
+			data = o.buf.Reset()
+			data = data[:len(data)-1] // trim \n
+			result = data
+			if !o.GetConfig().DisableAutoSaveHistory {
+				// ignore IO error
+				_ = o.history.New(data)
+			} else {
+				isUpdateHistory = false
+			}
+			o.undo.init()
+		case CharBackward:
+			o.buf.MoveBackward()
+		case CharForward:
+			o.buf.MoveForward()
+		case CharPrev:
+			buf := o.history.Prev()
+			if buf != nil {
+				o.buf.Set(buf)
+				o.undo.init()
+			} else {
+				o.t.Bell()
+			}
+		case CharNext:
+			buf, ok := o.history.Next()
+			if ok {
+				o.buf.Set(buf)
+				o.undo.init()
+			} else {
+				o.t.Bell()
+			}
+		case MetaDeleteKey, CharEOT:
+			o.undo.add()
+			// on Delete key or Ctrl-D, attempt to delete a character:
+			if o.buf.Len() > 0 || !o.IsNormalMode() {
+				if !o.buf.Delete() {
+					o.t.Bell()
+				}
+				break
+			}
+			if r != CharEOT {
+				break
+			}
+			// Ctrl-D on an empty buffer: treated as EOF
+			o.buf.WriteString(o.GetConfig().EOFPrompt + "\n")
+			o.buf.Reset()
+			isUpdateHistory = false
+			o.history.Revert()
+			o.buf.Clean()
+			return nil, io.EOF
+		case CharInterrupt:
+			if o.search.IsSearchMode() {
+				o.search.ExitSearchMode(true)
+				break
+			}
+			if o.completer.IsInCompleteMode() {
+				o.completer.ExitCompleteMode(true)
+				o.buf.Refresh(nil)
+				break
+			}
+			o.buf.MoveToLineEnd()
+			o.buf.Refresh(nil)
+			hint := o.GetConfig().InterruptPrompt + "\n"
+			o.buf.WriteString(hint)
+			remain := o.buf.Reset()
+			remain = remain[:len(remain)-len([]rune(hint))]
+			isUpdateHistory = false
+			o.history.Revert()
+			return nil, ErrInterrupt
+		case CharTab:
+			if o.GetConfig().AutoComplete != nil {
+				if o.completer.OnComplete() {
+					if o.completer.IsInCompleteMode() {
+						keepInCompleteMode = true
+						continue // redraw is done, loop
+					}
+				} else {
+					o.t.Bell()
+				}
+				o.buf.Refresh(nil)
+				break
+			} // else: process as a normal input character
+			fallthrough
+		default:
+			isTypingRune = true
+			if !isTyping {
+				o.undo.add()
+			}
+			if o.search.IsSearchMode() {
+				o.search.SearchChar(r)
+				keepInSearchMode = true
+				break
+			}
+			o.buf.WriteRune(r)
+			if o.completer.IsInCompleteMode() {
+				o.completer.OnComplete()
+				if o.completer.IsInCompleteMode() {
+					keepInCompleteMode = true
+				} else {
+					o.buf.Refresh(nil)
+				}
+			}
+		}
+
+		isTyping = isTypingRune
+
+		// suppress the Listener callback if we received Enter or similar and are
+		// submitting the result, since the buffer has already been cleared:
+		if result == nil {
+			if listener := o.GetConfig().Listener; listener != nil {
+				newLine, newPos, ok := listener(o.buf.Runes(), o.buf.Pos(), r)
+				if ok {
+					o.buf.SetWithIdx(newPos, newLine)
+				}
+			}
+		}
+
+		o.m.Lock()
+		if !keepInSearchMode && o.search.IsSearchMode() {
+			o.search.ExitSearchMode(false)
+			o.buf.Refresh(nil)
+			o.undo.init()
+		} else if o.completer.IsInCompleteMode() {
+			if !keepInCompleteMode {
+				o.completer.ExitCompleteMode(false)
+				o.refresh()
+				o.undo.init()
+			} else {
+				o.buf.Refresh(nil)
+				o.completer.CompleteRefresh()
+			}
+		}
+		if isUpdateHistory && !o.search.IsSearchMode() {
+			// it will cause null history
+			o.history.Update(o.buf.Runes(), false)
+		}
+		o.m.Unlock()
+
+		if result != nil {
+			return result, nil
+		}
+	}
+}
+
+func (o *operation) Stderr() io.Writer {
+	return o.wrapErr.Load()
+}
+
+func (o *operation) Stdout() io.Writer {
+	return o.wrapOut.Load()
+}
+
+func (o *operation) String() (string, error) {
+	r, err := o.Runes()
+	return string(r), err
+}
+
+func (o *operation) Runes() ([]rune, error) {
+	o.t.EnterRawMode()
+	defer o.t.ExitRawMode()
+
+	cfg := o.GetConfig()
+	listener := cfg.Listener
+	if listener != nil {
+		listener(nil, 0, 0)
+	}
+
+	// Before writing the prompt and starting to read, get a lock
+	// so we don't race with wrapWriter trying to write and refresh.
+	o.m.Lock()
+	o.isPrompting = true
+	// Query cursor position before printing the prompt as there
+	// may be existing text on the same line that ideally we don't
+	// want to overwrite and cause prompt to jump left.
+	o.getAndSetOffset(nil)
+	o.buf.Print() // print prompt & buffer contents
+	// Prompt written safely, unlock until read completes and then
+	// lock again to unset.
+	o.m.Unlock()
+
+	if cfg.Undo {
+		o.undo = newOpUndo(o)
+	}
+
+	defer func() {
+		o.m.Lock()
+		o.isPrompting = false
+		o.buf.SetOffset(cursorPosition{1, 1})
+		o.m.Unlock()
+	}()
+
+	return o.readline(nil)
+}
+
+func (o *operation) getAndSetOffset(deadline chan struct{}) {
+	if !o.GetConfig().isInteractive {
+		return
+	}
+
+	// Handle lineedge cases where existing text before before
+	// the prompt is printed would leave us at the right edge of
+	// the screen but the next character would actually be printed
+	// at the beginning of the next line.
+	// TODO ???
+	o.t.Write([]byte(" \b"))
+
+	if offset, err := o.t.GetCursorPosition(deadline); err == nil {
+		o.buf.SetOffset(offset)
+	}
+}
+
+func (o *operation) GenPasswordConfig() *Config {
+	baseConfig := o.GetConfig()
+	return &Config{
+		EnableMask:      true,
+		InterruptPrompt: "\n",
+		EOFPrompt:       "\n",
+		HistoryLimit:    -1,
+
+		Stdin:  baseConfig.Stdin,
+		Stdout: baseConfig.Stdout,
+		Stderr: baseConfig.Stderr,
+
+		FuncIsTerminal:     baseConfig.FuncIsTerminal,
+		FuncMakeRaw:        baseConfig.FuncMakeRaw,
+		FuncExitRaw:        baseConfig.FuncExitRaw,
+		FuncOnWidthChanged: baseConfig.FuncOnWidthChanged,
+	}
+}
+
+func (o *operation) ReadLineWithConfig(cfg *Config) (string, error) {
+	backupCfg, err := o.SetConfig(cfg)
+	if err != nil {
+		return "", err
+	}
+	defer func() {
+		o.SetConfig(backupCfg)
+	}()
+	return o.String()
+}
+
+func (o *operation) SetTitle(t string) {
+	o.t.Write([]byte("\033[2;" + t + "\007"))
+}
+
+func (o *operation) Slice() ([]byte, error) {
+	r, err := o.Runes()
+	if err != nil {
+		return nil, err
+	}
+	return []byte(string(r)), nil
+}
+
+func (o *operation) Close() {
+	o.history.Close()
+}
+
+func (o *operation) IsNormalMode() bool {
+	return !o.completer.IsInCompleteMode() && !o.search.IsSearchMode()
+}
+
+func (op *operation) SetConfig(cfg *Config) (*Config, error) {
+	op.m.Lock()
+	defer op.m.Unlock()
+	old := op.t.GetConfig()
+	if err := cfg.init(); err != nil {
+		return old, err
+	}
+
+	// install the config in its canonical location (inside terminal):
+	op.t.SetConfig(cfg)
+
+	op.wrapOut.Store(&wrapWriter{target: cfg.Stdout, o: op})
+	op.wrapErr.Store(&wrapWriter{target: cfg.Stderr, o: op})
+
+	if op.history == nil {
+		op.history = newOpHistory(op)
+	}
+	if op.search == nil {
+		op.search = newOpSearch(op.buf.w, op.buf, op.history)
+	}
+
+	if cfg.AutoComplete != nil && op.completer == nil {
+		op.completer = newOpCompleter(op.buf.w, op)
+	}
+
+	return old, nil
+}
+
+func (o *operation) ResetHistory() {
+	o.history.Reset()
+}
+
+func (o *operation) SaveToHistory(content string) error {
+	return o.history.New([]rune(content))
+}
+
+func (o *operation) Refresh() {
+	o.m.Lock()
+	defer o.m.Unlock()
+	o.refresh()
+}
+
+func (o *operation) refresh() {
+	if o.isPrompting {
+		o.buf.Refresh(nil)
+	}
+}

vendor/github.com/ergochat/readline/readline.go

@@ -0,0 +1,319 @@
+package readline
+
+import (
+	"io"
+	"os"
+	"os/signal"
+	"sync"
+	"syscall"
+
+	"github.com/ergochat/readline/internal/platform"
+)
+
+type Instance struct {
+	terminal  *terminal
+	operation *operation
+
+	closeOnce sync.Once
+	closeErr  error
+}
+
+type Config struct {
+	// Prompt is the input prompt (ANSI escape sequences are supported on all platforms)
+	Prompt string
+
+	// HistoryFile is the path to the file where persistent history will be stored
+	// (empty string disables).
+	HistoryFile string
+	// HistoryLimit is the maximum number of history entries to store. If it is 0
+	// or unset, the default value is 500; set to -1 to disable.
+	HistoryLimit           int
+	DisableAutoSaveHistory bool
+	// HistorySearchFold enables case-insensitive history searching.
+	HistorySearchFold bool
+
+	// AutoComplete defines the tab-completion behavior. See the documentation for
+	// the AutoCompleter interface for details.
+	AutoComplete AutoCompleter
+
+	// Listener is an optional callback to intercept keypresses.
+	Listener Listener
+
+	// Painter is an optional callback to rewrite the buffer for display.
+	Painter Painter
+
+	// FuncFilterInputRune is an optional callback to translate keyboard inputs;
+	// it takes in the input rune and returns (translation, ok). If ok is false,
+	// the rune is skipped.
+	FuncFilterInputRune func(rune) (rune, bool)
+
+	// VimMode enables Vim-style insert mode by default.
+	VimMode bool
+
+	InterruptPrompt string
+	EOFPrompt       string
+
+	EnableMask bool
+	MaskRune   rune
+
+	// Undo controls whether to maintain an undo buffer (if enabled,
+	// Ctrl+_ will undo the previous action).
+	Undo bool
+
+	// These fields allow customizing terminal handling. Most clients should ignore them.
+	Stdin              io.Reader
+	Stdout             io.Writer
+	Stderr             io.Writer
+	FuncIsTerminal     func() bool
+	FuncMakeRaw        func() error
+	FuncExitRaw        func() error
+	FuncGetSize        func() (width int, height int)
+	FuncOnWidthChanged func(func())
+
+	// private fields
+	inited        bool
+	isInteractive bool
+}
+
+func (c *Config) init() error {
+	if c.inited {
+		return nil
+	}
+	c.inited = true
+	if c.Stdin == nil {
+		c.Stdin = os.Stdin
+	}
+
+	if c.Stdout == nil {
+		c.Stdout = os.Stdout
+	}
+	if c.Stderr == nil {
+		c.Stderr = os.Stderr
+	}
+	if c.HistoryLimit == 0 {
+		c.HistoryLimit = 500
+	}
+
+	if c.InterruptPrompt == "" {
+		c.InterruptPrompt = "^C"
+	} else if c.InterruptPrompt == "\n" {
+		c.InterruptPrompt = ""
+	}
+	if c.EOFPrompt == "" {
+		c.EOFPrompt = "^D"
+	} else if c.EOFPrompt == "\n" {
+		c.EOFPrompt = ""
+	}
+
+	if c.FuncGetSize == nil {
+		c.FuncGetSize = platform.GetScreenSize
+	}
+	if c.FuncIsTerminal == nil {
+		c.FuncIsTerminal = platform.DefaultIsTerminal
+	}
+	rm := new(rawModeHandler)
+	if c.FuncMakeRaw == nil {
+		c.FuncMakeRaw = rm.Enter
+	}
+	if c.FuncExitRaw == nil {
+		c.FuncExitRaw = rm.Exit
+	}
+	if c.FuncOnWidthChanged == nil {
+		c.FuncOnWidthChanged = platform.DefaultOnSizeChanged
+	}
+	if c.Painter == nil {
+		c.Painter = defaultPainter
+	}
+
+	c.isInteractive = c.FuncIsTerminal()
+
+	return nil
+}
+
+// NewFromConfig creates a readline instance from the specified configuration.
+func NewFromConfig(cfg *Config) (*Instance, error) {
+	if err := cfg.init(); err != nil {
+		return nil, err
+	}
+	t, err := newTerminal(cfg)
+	if err != nil {
+		return nil, err
+	}
+	o := newOperation(t)
+	return &Instance{
+		terminal:  t,
+		operation: o,
+	}, nil
+}
+
+// NewEx is an alias for NewFromConfig, for compatibility.
+var NewEx = NewFromConfig
+
+// New creates a readline instance with default configuration.
+func New(prompt string) (*Instance, error) {
+	return NewFromConfig(&Config{Prompt: prompt})
+}
+
+func (i *Instance) ResetHistory() {
+	i.operation.ResetHistory()
+}
+
+func (i *Instance) SetPrompt(s string) {
+	cfg := i.GetConfig()
+	cfg.Prompt = s
+	i.SetConfig(cfg)
+}
+
+// readline will refresh automatic when write through Stdout()
+func (i *Instance) Stdout() io.Writer {
+	return i.operation.Stdout()
+}
+
+// readline will refresh automatic when write through Stdout()
+func (i *Instance) Stderr() io.Writer {
+	return i.operation.Stderr()
+}
+
+// switch VimMode in runtime
+func (i *Instance) SetVimMode(on bool) {
+	cfg := i.GetConfig()
+	cfg.VimMode = on
+	i.SetConfig(cfg)
+}
+
+func (i *Instance) IsVimMode() bool {
+	return i.operation.vim.IsEnableVimMode()
+}
+
+// GeneratePasswordConfig generates a suitable Config for reading passwords;
+// this config can be modified and then used with ReadLineWithConfig, or
+// SetConfig.
+func (i *Instance) GeneratePasswordConfig() *Config {
+	return i.operation.GenPasswordConfig()
+}
+
+func (i *Instance) ReadLineWithConfig(cfg *Config) (string, error) {
+	return i.operation.ReadLineWithConfig(cfg)
+}
+
+func (i *Instance) ReadPassword(prompt string) ([]byte, error) {
+	if result, err := i.ReadLineWithConfig(i.GeneratePasswordConfig()); err == nil {
+		return []byte(result), nil
+	} else {
+		return nil, err
+	}
+}
+
+// ReadLine reads a line from the configured input source, allowing inline editing.
+// The returned error is either nil, io.EOF, or readline.ErrInterrupt.
+func (i *Instance) ReadLine() (string, error) {
+	return i.operation.String()
+}
+
+// Readline is an alias for ReadLine, for compatibility.
+func (i *Instance) Readline() (string, error) {
+	return i.ReadLine()
+}
+
+// SetDefault prefills a default value for the next call to Readline()
+// or related methods. The value will appear after the prompt for the user
+// to edit, with the cursor at the end of the line.
+func (i *Instance) SetDefault(defaultValue string) {
+	i.operation.SetBuffer(defaultValue)
+}
+
+func (i *Instance) ReadLineWithDefault(defaultValue string) (string, error) {
+	i.SetDefault(defaultValue)
+	return i.operation.String()
+}
+
+// SaveToHistory adds a string to the instance's stored history. This is particularly
+// relevant when DisableAutoSaveHistory is configured.
+func (i *Instance) SaveToHistory(content string) error {
+	return i.operation.SaveToHistory(content)
+}
+
+// same as readline
+func (i *Instance) ReadSlice() ([]byte, error) {
+	return i.operation.Slice()
+}
+
+// Close() closes the readline instance, cleaning up state changes to the
+// terminal. It interrupts any concurrent Readline() operation, so it can be
+// asynchronously or from a signal handler. It is concurrency-safe and
+// idempotent, so it can be called multiple times.
+func (i *Instance) Close() error {
+	i.closeOnce.Do(func() {
+		// TODO reorder these?
+		i.operation.Close()
+		i.closeErr = i.terminal.Close()
+	})
+	return i.closeErr
+}
+
+// CaptureExitSignal registers handlers for common exit signals that will
+// close the readline instance.
+func (i *Instance) CaptureExitSignal() {
+	cSignal := make(chan os.Signal, 1)
+	// TODO handle other signals in a portable way?
+	signal.Notify(cSignal, os.Interrupt, syscall.SIGTERM)
+	go func() {
+		for range cSignal {
+			i.Close()
+		}
+	}()
+}
+
+// Write writes output to the screen, redrawing the prompt and buffer
+// as needed.
+func (i *Instance) Write(b []byte) (int, error) {
+	return i.Stdout().Write(b)
+}
+
+// GetConfig returns a copy of the current config.
+func (i *Instance) GetConfig() *Config {
+	cfg := i.operation.GetConfig()
+	result := new(Config)
+	*result = *cfg
+	return result
+}
+
+// SetConfig modifies the current instance's config.
+func (i *Instance) SetConfig(cfg *Config) error {
+	_, err := i.operation.SetConfig(cfg)
+	return err
+}
+
+// Refresh redraws the input buffer on screen.
+func (i *Instance) Refresh() {
+	i.operation.Refresh()
+}
+
+// DisableHistory disables the saving of input lines in history.
+func (i *Instance) DisableHistory() {
+	i.operation.history.Disable()
+}
+
+// EnableHistory enables the saving of input lines in history.
+func (i *Instance) EnableHistory() {
+	i.operation.history.Enable()
+}
+
+// ClearScreen clears the screen.
+func (i *Instance) ClearScreen() {
+	clearScreen(i.operation.Stdout())
+}
+
+// Painter is a callback type to allow modifying the buffer before it is rendered
+// on screen, for example, to implement real-time syntax highlighting.
+type Painter func(line []rune, pos int) []rune
+
+func defaultPainter(line []rune, _ int) []rune {
+	return line
+}
+
+// Listener is a callback type to listen for keypresses while the line is being
+// edited. It is invoked initially with (nil, 0, 0), and then subsequently for
+// any keypress until (but not including) the newline/enter keypress that completes
+// the input.
+type Listener func(line []rune, pos int, key rune) (newLine []rune, newPos int, ok bool)

vendor/github.com/ergochat/readline/runebuf.go

@@ -0,0 +1,684 @@
+package readline
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"io"
+	"strings"
+	"sync"
+
+	"github.com/ergochat/readline/internal/runes"
+)
+
+type runeBuffer struct {
+	buf []rune
+	idx int
+	w   *terminal
+
+	cpos cursorPosition
+	ppos int // prompt start position (0 == column 1)
+
+	lastKill []rune
+
+	sync.Mutex
+}
+
+func (r *runeBuffer) pushKill(text []rune) {
+	r.lastKill = append([]rune{}, text...)
+}
+
+func newRuneBuffer(w *terminal) *runeBuffer {
+	rb := &runeBuffer{
+		w: w,
+	}
+	return rb
+}
+
+func (r *runeBuffer) CurrentWidth(x int) int {
+	r.Lock()
+	defer r.Unlock()
+	return runes.WidthAll(r.buf[:x])
+}
+
+func (r *runeBuffer) PromptLen() int {
+	r.Lock()
+	defer r.Unlock()
+	return r.promptLen()
+}
+
+func (r *runeBuffer) promptLen() int {
+	return runes.WidthAll(runes.ColorFilter([]rune(r.prompt())))
+}
+
+func (r *runeBuffer) RuneSlice(i int) []rune {
+	r.Lock()
+	defer r.Unlock()
+
+	if i > 0 {
+		rs := make([]rune, i)
+		copy(rs, r.buf[r.idx:r.idx+i])
+		return rs
+	}
+	rs := make([]rune, -i)
+	copy(rs, r.buf[r.idx+i:r.idx])
+	return rs
+}
+
+func (r *runeBuffer) Runes() []rune {
+	r.Lock()
+	newr := make([]rune, len(r.buf))
+	copy(newr, r.buf)
+	r.Unlock()
+	return newr
+}
+
+func (r *runeBuffer) Pos() int {
+	r.Lock()
+	defer r.Unlock()
+	return r.idx
+}
+
+func (r *runeBuffer) Len() int {
+	r.Lock()
+	defer r.Unlock()
+	return len(r.buf)
+}
+
+func (r *runeBuffer) MoveToLineStart() {
+	r.Refresh(func() {
+		r.idx = 0
+	})
+}
+
+func (r *runeBuffer) MoveBackward() {
+	r.Refresh(func() {
+		if r.idx == 0 {
+			return
+		}
+		r.idx--
+	})
+}
+
+func (r *runeBuffer) WriteString(s string) {
+	r.WriteRunes([]rune(s))
+}
+
+func (r *runeBuffer) WriteRune(s rune) {
+	r.WriteRunes([]rune{s})
+}
+
+func (r *runeBuffer) getConfig() *Config {
+	return r.w.GetConfig()
+}
+
+func (r *runeBuffer) isInteractive() bool {
+	return r.getConfig().isInteractive
+}
+
+func (r *runeBuffer) prompt() string {
+	return r.getConfig().Prompt
+}
+
+func (r *runeBuffer) WriteRunes(s []rune) {
+	r.Lock()
+	defer r.Unlock()
+
+	if r.idx == len(r.buf) {
+		// cursor is already at end of buf data so just call
+		// append instead of refesh to save redrawing.
+		r.buf = append(r.buf, s...)
+		r.idx += len(s)
+		if r.isInteractive() {
+			r.append(s)
+		}
+	} else {
+		// writing into the data somewhere so do a refresh
+		r.refresh(func() {
+			tail := append(s, r.buf[r.idx:]...)
+			r.buf = append(r.buf[:r.idx], tail...)
+			r.idx += len(s)
+		})
+	}
+}
+
+func (r *runeBuffer) MoveForward() {
+	r.Refresh(func() {
+		if r.idx == len(r.buf) {
+			return
+		}
+		r.idx++
+	})
+}
+
+func (r *runeBuffer) IsCursorInEnd() bool {
+	r.Lock()
+	defer r.Unlock()
+	return r.idx == len(r.buf)
+}
+
+func (r *runeBuffer) Replace(ch rune) {
+	r.Refresh(func() {
+		r.buf[r.idx] = ch
+	})
+}
+
+func (r *runeBuffer) Erase() {
+	r.Refresh(func() {
+		r.idx = 0
+		r.pushKill(r.buf[:])
+		r.buf = r.buf[:0]
+	})
+}
+
+func (r *runeBuffer) Delete() (success bool) {
+	r.Refresh(func() {
+		if r.idx == len(r.buf) {
+			return
+		}
+		r.pushKill(r.buf[r.idx : r.idx+1])
+		r.buf = append(r.buf[:r.idx], r.buf[r.idx+1:]...)
+		success = true
+	})
+	return
+}
+
+func (r *runeBuffer) DeleteWord() {
+	if r.idx == len(r.buf) {
+		return
+	}
+	init := r.idx
+	for init < len(r.buf) && runes.IsWordBreak(r.buf[init]) {
+		init++
+	}
+	for i := init + 1; i < len(r.buf); i++ {
+		if !runes.IsWordBreak(r.buf[i]) && runes.IsWordBreak(r.buf[i-1]) {
+			r.pushKill(r.buf[r.idx : i-1])
+			r.Refresh(func() {
+				r.buf = append(r.buf[:r.idx], r.buf[i-1:]...)
+			})
+			return
+		}
+	}
+	r.Kill()
+}
+
+func (r *runeBuffer) MoveToPrevWord() (success bool) {
+	r.Refresh(func() {
+		if r.idx == 0 {
+			return
+		}
+
+		for i := r.idx - 1; i > 0; i-- {
+			if !runes.IsWordBreak(r.buf[i]) && runes.IsWordBreak(r.buf[i-1]) {
+				r.idx = i
+				success = true
+				return
+			}
+		}
+		r.idx = 0
+		success = true
+	})
+	return
+}
+
+func (r *runeBuffer) KillFront() {
+	r.Refresh(func() {
+		if r.idx == 0 {
+			return
+		}
+
+		length := len(r.buf) - r.idx
+		r.pushKill(r.buf[:r.idx])
+		copy(r.buf[:length], r.buf[r.idx:])
+		r.idx = 0
+		r.buf = r.buf[:length]
+	})
+}
+
+func (r *runeBuffer) Kill() {
+	r.Refresh(func() {
+		r.pushKill(r.buf[r.idx:])
+		r.buf = r.buf[:r.idx]
+	})
+}
+
+func (r *runeBuffer) Transpose() {
+	r.Refresh(func() {
+		if r.idx == 0 {
+			// match the GNU Readline behavior, Ctrl-T at the start of the line
+			// is a no-op:
+			return
+		}
+
+		// OK, we have at least one character behind us:
+		if r.idx < len(r.buf) {
+			// swap the character in front of us with the one behind us
+			r.buf[r.idx], r.buf[r.idx-1] = r.buf[r.idx-1], r.buf[r.idx]
+			// advance the cursor
+			r.idx++
+		} else if r.idx == len(r.buf) && len(r.buf) >= 2 {
+			// swap the two characters behind us
+			r.buf[r.idx-2], r.buf[r.idx-1] = r.buf[r.idx-1], r.buf[r.idx-2]
+			// leave the cursor in place since there's nowhere to go
+		}
+	})
+}
+
+func (r *runeBuffer) MoveToNextWord() {
+	r.Refresh(func() {
+		for i := r.idx + 1; i < len(r.buf); i++ {
+			if !runes.IsWordBreak(r.buf[i]) && runes.IsWordBreak(r.buf[i-1]) {
+				r.idx = i
+				return
+			}
+		}
+
+		r.idx = len(r.buf)
+	})
+}
+
+func (r *runeBuffer) MoveToEndWord() {
+	r.Refresh(func() {
+		// already at the end, so do nothing
+		if r.idx == len(r.buf) {
+			return
+		}
+		// if we are at the end of a word already, go to next
+		if !runes.IsWordBreak(r.buf[r.idx]) && runes.IsWordBreak(r.buf[r.idx+1]) {
+			r.idx++
+		}
+
+		// keep going until at the end of a word
+		for i := r.idx + 1; i < len(r.buf); i++ {
+			if runes.IsWordBreak(r.buf[i]) && !runes.IsWordBreak(r.buf[i-1]) {
+				r.idx = i - 1
+				return
+			}
+		}
+		r.idx = len(r.buf)
+	})
+}
+
+func (r *runeBuffer) BackEscapeWord() {
+	r.Refresh(func() {
+		if r.idx == 0 {
+			return
+		}
+		for i := r.idx - 1; i >= 0; i-- {
+			if i == 0 || (runes.IsWordBreak(r.buf[i-1])) && !runes.IsWordBreak(r.buf[i]) {
+				r.pushKill(r.buf[i:r.idx])
+				r.buf = append(r.buf[:i], r.buf[r.idx:]...)
+				r.idx = i
+				return
+			}
+		}
+
+		r.buf = r.buf[:0]
+		r.idx = 0
+	})
+}
+
+func (r *runeBuffer) Yank() {
+	if len(r.lastKill) == 0 {
+		return
+	}
+	r.Refresh(func() {
+		buf := make([]rune, 0, len(r.buf)+len(r.lastKill))
+		buf = append(buf, r.buf[:r.idx]...)
+		buf = append(buf, r.lastKill...)
+		buf = append(buf, r.buf[r.idx:]...)
+		r.buf = buf
+		r.idx += len(r.lastKill)
+	})
+}
+
+func (r *runeBuffer) Backspace() {
+	r.Refresh(func() {
+		if r.idx == 0 {
+			return
+		}
+
+		r.idx--
+		r.buf = append(r.buf[:r.idx], r.buf[r.idx+1:]...)
+	})
+}
+
+func (r *runeBuffer) MoveToLineEnd() {
+	r.Lock()
+	defer r.Unlock()
+	if r.idx == len(r.buf) {
+		return
+	}
+	r.refresh(func() {
+		r.idx = len(r.buf)
+	})
+}
+
+// LineCount returns number of lines the buffer takes as it appears in the terminal.
+func (r *runeBuffer) LineCount() int {
+	sp := r.getSplitByLine(r.buf, 1)
+	return len(sp)
+}
+
+func (r *runeBuffer) MoveTo(ch rune, prevChar, reverse bool) (success bool) {
+	r.Refresh(func() {
+		if reverse {
+			for i := r.idx - 1; i >= 0; i-- {
+				if r.buf[i] == ch {
+					r.idx = i
+					if prevChar {
+						r.idx++
+					}
+					success = true
+					return
+				}
+			}
+			return
+		}
+		for i := r.idx + 1; i < len(r.buf); i++ {
+			if r.buf[i] == ch {
+				r.idx = i
+				if prevChar {
+					r.idx--
+				}
+				success = true
+				return
+			}
+		}
+	})
+	return
+}
+
+func (r *runeBuffer) isInLineEdge() bool {
+	sp := r.getSplitByLine(r.buf, 1)
+	return len(sp[len(sp)-1]) == 0 // last line is 0 len
+}
+
+func (r *runeBuffer) getSplitByLine(rs []rune, nextWidth int) [][]rune {
+	tWidth, _ := r.w.GetWidthHeight()
+	cfg := r.getConfig()
+	if cfg.EnableMask {
+		w := runes.Width(cfg.MaskRune)
+		masked := []rune(strings.Repeat(string(cfg.MaskRune), len(rs)))
+		return runes.SplitByLine(runes.ColorFilter([]rune(r.prompt())), masked, r.ppos, tWidth, w)
+	} else {
+		return runes.SplitByLine(runes.ColorFilter([]rune(r.prompt())), rs, r.ppos, tWidth, nextWidth)
+	}
+}
+
+func (r *runeBuffer) IdxLine(width int) int {
+	r.Lock()
+	defer r.Unlock()
+	return r.idxLine(width)
+}
+
+func (r *runeBuffer) idxLine(width int) int {
+	if width == 0 {
+		return 0
+	}
+	nextWidth := 1
+	if r.idx < len(r.buf) {
+		nextWidth = runes.Width(r.buf[r.idx])
+	}
+	sp := r.getSplitByLine(r.buf[:r.idx], nextWidth)
+	return len(sp) - 1
+}
+
+func (r *runeBuffer) CursorLineCount() int {
+	tWidth, _ := r.w.GetWidthHeight()
+	return r.LineCount() - r.IdxLine(tWidth)
+}
+
+func (r *runeBuffer) Refresh(f func()) {
+	r.Lock()
+	defer r.Unlock()
+	r.refresh(f)
+}
+
+func (r *runeBuffer) refresh(f func()) {
+	if !r.isInteractive() {
+		if f != nil {
+			f()
+		}
+		return
+	}
+
+	r.clean()
+	if f != nil {
+		f()
+	}
+	r.print()
+}
+
+func (r *runeBuffer) SetOffset(position cursorPosition) {
+	r.Lock()
+	defer r.Unlock()
+	r.setOffset(position)
+}
+
+func (r *runeBuffer) setOffset(cpos cursorPosition) {
+	r.cpos = cpos
+	tWidth, _ := r.w.GetWidthHeight()
+	if cpos.col > 0 && cpos.col < tWidth {
+		r.ppos = cpos.col - 1 // c should be 1..tWidth
+	} else {
+		r.ppos = 0
+	}
+}
+
+// append s to the end of the current output. append is called in
+// place of print() when clean() was avoided. As output is appended on
+// the end, the cursor also needs no extra adjustment.
+// NOTE: assumes len(s) >= 1 which should always be true for append.
+func (r *runeBuffer) append(s []rune) {
+	buf := bytes.NewBuffer(nil)
+	slen := len(s)
+	cfg := r.getConfig()
+	if cfg.EnableMask {
+		if slen > 1 && cfg.MaskRune != 0 {
+			// write a mask character for all runes except the last rune
+			buf.WriteString(strings.Repeat(string(cfg.MaskRune), slen-1))
+		}
+		// for the last rune, write \n or mask it otherwise.
+		if s[slen-1] == '\n' {
+			buf.WriteRune('\n')
+		} else if cfg.MaskRune != 0 {
+			buf.WriteRune(cfg.MaskRune)
+		}
+	} else {
+		for _, e := range cfg.Painter(s, slen) {
+			if e == '\t' {
+				buf.WriteString(strings.Repeat(" ", runes.TabWidth))
+			} else {
+				buf.WriteRune(e)
+			}
+		}
+	}
+	if r.isInLineEdge() {
+		buf.WriteString(" \b")
+	}
+	r.w.Write(buf.Bytes())
+}
+
+// Print writes out the prompt and buffer contents at the current cursor position
+func (r *runeBuffer) Print() {
+	r.Lock()
+	defer r.Unlock()
+	if !r.isInteractive() {
+		return
+	}
+	r.print()
+}
+
+func (r *runeBuffer) print() {
+	r.w.Write(r.output())
+}
+
+func (r *runeBuffer) output() []byte {
+	buf := bytes.NewBuffer(nil)
+	buf.WriteString(r.prompt())
+	buf.WriteString("\x1b[0K") // VT100 "Clear line from cursor right", see #38
+	cfg := r.getConfig()
+	if cfg.EnableMask && len(r.buf) > 0 {
+		if cfg.MaskRune != 0 {
+			buf.WriteString(strings.Repeat(string(cfg.MaskRune), len(r.buf)-1))
+		}
+		if r.buf[len(r.buf)-1] == '\n' {
+			buf.WriteRune('\n')
+		} else if cfg.MaskRune != 0 {
+			buf.WriteRune(cfg.MaskRune)
+		}
+	} else {
+		for _, e := range cfg.Painter(r.buf, r.idx) {
+			if e == '\t' {
+				buf.WriteString(strings.Repeat(" ", runes.TabWidth))
+			} else {
+				buf.WriteRune(e)
+			}
+		}
+	}
+	if r.isInLineEdge() {
+		buf.WriteString(" \b")
+	}
+	// cursor position
+	if len(r.buf) > r.idx {
+		buf.Write(r.getBackspaceSequence())
+	}
+	return buf.Bytes()
+}
+
+func (r *runeBuffer) getBackspaceSequence() []byte {
+	bcnt := len(r.buf) - r.idx // backwards count to index
+	sp := r.getSplitByLine(r.buf, 1)
+
+	// Calculate how many lines up to the index line
+	up := 0
+	spi := len(sp) - 1
+	for spi >= 0 {
+		bcnt -= len(sp[spi])
+		if bcnt <= 0 {
+			break
+		}
+		up++
+		spi--
+	}
+
+	// Calculate what column the index should be set to
+	column := 1
+	if spi == 0 {
+		column += r.ppos
+	}
+	for _, rune := range sp[spi] {
+		if bcnt >= 0 {
+			break
+		}
+		column += runes.Width(rune)
+		bcnt++
+	}
+
+	buf := bytes.NewBuffer(nil)
+	if up > 0 {
+		fmt.Fprintf(buf, "\033[%dA", up) // move cursor up to index line
+	}
+	fmt.Fprintf(buf, "\033[%dG", column) // move cursor to column
+
+	return buf.Bytes()
+}
+
+func (r *runeBuffer) CopyForUndo(prev []rune) (cur []rune, idx int, changed bool) {
+	if runes.Equal(r.buf, prev) {
+		return prev, r.idx, false
+	} else {
+		return runes.Copy(r.buf), r.idx, true
+	}
+}
+
+func (r *runeBuffer) Restore(buf []rune, idx int) {
+	r.buf = buf
+	r.idx = idx
+}
+
+func (r *runeBuffer) Reset() []rune {
+	ret := runes.Copy(r.buf)
+	r.buf = r.buf[:0]
+	r.idx = 0
+	return ret
+}
+
+func (r *runeBuffer) calWidth(m int) int {
+	if m > 0 {
+		return runes.WidthAll(r.buf[r.idx : r.idx+m])
+	}
+	return runes.WidthAll(r.buf[r.idx+m : r.idx])
+}
+
+func (r *runeBuffer) SetStyle(start, end int, style string) {
+	if end < start {
+		panic("end < start")
+	}
+
+	// goto start
+	move := start - r.idx
+	if move > 0 {
+		r.w.Write([]byte(string(r.buf[r.idx : r.idx+move])))
+	} else {
+		r.w.Write(bytes.Repeat([]byte("\b"), r.calWidth(move)))
+	}
+	r.w.Write([]byte("\033[" + style + "m"))
+	r.w.Write([]byte(string(r.buf[start:end])))
+	r.w.Write([]byte("\033[0m"))
+	// TODO: move back
+}
+
+func (r *runeBuffer) SetWithIdx(idx int, buf []rune) {
+	r.Refresh(func() {
+		r.buf = buf
+		r.idx = idx
+	})
+}
+
+func (r *runeBuffer) Set(buf []rune) {
+	r.SetWithIdx(len(buf), buf)
+}
+
+func (r *runeBuffer) SetNoRefresh(buf []rune) {
+	r.buf = buf
+	r.idx = len(buf)
+}
+
+func (r *runeBuffer) cleanOutput(w io.Writer, idxLine int) {
+	buf := bufio.NewWriter(w)
+
+	tWidth, _ := r.w.GetWidthHeight()
+	if tWidth == 0 {
+		buf.WriteString(strings.Repeat("\r\b", len(r.buf)+r.promptLen()))
+		buf.Write([]byte("\033[J"))
+	} else {
+		if idxLine > 0 {
+			fmt.Fprintf(buf, "\033[%dA", idxLine) // move cursor up by idxLine
+		}
+		fmt.Fprintf(buf, "\033[%dG", r.ppos+1) // move cursor back to initial ppos position
+		buf.Write([]byte("\033[J"))            // clear from cursor to end of screen
+	}
+	buf.Flush()
+	return
+}
+
+func (r *runeBuffer) Clean() {
+	r.Lock()
+	r.clean()
+	r.Unlock()
+}
+
+func (r *runeBuffer) clean() {
+	tWidth, _ := r.w.GetWidthHeight()
+	r.cleanWithIdxLine(r.idxLine(tWidth))
+}
+
+func (r *runeBuffer) cleanWithIdxLine(idxLine int) {
+	if !r.isInteractive() {
+		return
+	}
+	r.cleanOutput(r.w, idxLine)
+}

vendor/github.com/ergochat/readline/search.go

@@ -0,0 +1,189 @@
+package readline
+
+import (
+	"bytes"
+	"container/list"
+	"fmt"
+	"sync"
+)
+
+type searchState uint
+
+const (
+	searchStateFound searchState = iota
+	searchStateFailing
+)
+
+type searchDirection uint
+
+const (
+	searchDirectionForward searchDirection = iota
+	searchDirectionBackward
+)
+
+type opSearch struct {
+	mutex     sync.Mutex
+	inMode    bool
+	state     searchState
+	dir       searchDirection
+	source    *list.Element
+	w         *terminal
+	buf       *runeBuffer
+	data      []rune
+	history   *opHistory
+	markStart int
+	markEnd   int
+}
+
+func newOpSearch(w *terminal, buf *runeBuffer, history *opHistory) *opSearch {
+	return &opSearch{
+		w:       w,
+		buf:     buf,
+		history: history,
+	}
+}
+
+func (o *opSearch) IsSearchMode() bool {
+	o.mutex.Lock()
+	defer o.mutex.Unlock()
+	return o.inMode
+}
+
+func (o *opSearch) SearchBackspace() {
+	o.mutex.Lock()
+	defer o.mutex.Unlock()
+	if len(o.data) > 0 {
+		o.data = o.data[:len(o.data)-1]
+		o.search(true)
+	}
+}
+
+func (o *opSearch) findHistoryBy(isNewSearch bool) (int, *list.Element) {
+	if o.dir == searchDirectionBackward {
+		return o.history.FindBck(isNewSearch, o.data, o.buf.idx)
+	}
+	return o.history.FindFwd(isNewSearch, o.data, o.buf.idx)
+}
+
+func (o *opSearch) search(isChange bool) bool {
+	if len(o.data) == 0 {
+		o.state = searchStateFound
+		o.searchRefresh(-1)
+		return true
+	}
+	idx, elem := o.findHistoryBy(isChange)
+	if elem == nil {
+		o.searchRefresh(-2)
+		return false
+	}
+	o.history.current = elem
+
+	item := o.history.showItem(o.history.current.Value)
+	start, end := 0, 0
+	if o.dir == searchDirectionBackward {
+		start, end = idx, idx+len(o.data)
+	} else {
+		start, end = idx, idx+len(o.data)
+		idx += len(o.data)
+	}
+	o.buf.SetWithIdx(idx, item)
+	o.markStart, o.markEnd = start, end
+	o.searchRefresh(idx)
+	return true
+}
+
+func (o *opSearch) SearchChar(r rune) {
+	o.mutex.Lock()
+	defer o.mutex.Unlock()
+
+	o.data = append(o.data, r)
+	o.search(true)
+}
+
+func (o *opSearch) SearchMode(dir searchDirection) bool {
+	o.mutex.Lock()
+	defer o.mutex.Unlock()
+
+	tWidth, _ := o.w.GetWidthHeight()
+	if tWidth == 0 {
+		return false
+	}
+	alreadyInMode := o.inMode
+	o.inMode = true
+	o.dir = dir
+	o.source = o.history.current
+	if alreadyInMode {
+		o.search(false)
+	} else {
+		o.searchRefresh(-1)
+	}
+	return true
+}
+
+func (o *opSearch) ExitSearchMode(revert bool) {
+	o.mutex.Lock()
+	defer o.mutex.Unlock()
+
+	if revert {
+		o.history.current = o.source
+		var redrawValue []rune
+		if o.history.current != nil {
+			redrawValue = o.history.showItem(o.history.current.Value)
+		}
+		o.buf.Set(redrawValue)
+	}
+	o.markStart, o.markEnd = 0, 0
+	o.state = searchStateFound
+	o.inMode = false
+	o.source = nil
+	o.data = nil
+}
+
+func (o *opSearch) searchRefresh(x int) {
+	tWidth, _ := o.w.GetWidthHeight()
+	if x == -2 {
+		o.state = searchStateFailing
+	} else if x >= 0 {
+		o.state = searchStateFound
+	}
+	if x < 0 {
+		x = o.buf.idx
+	}
+	x = o.buf.CurrentWidth(x)
+	x += o.buf.PromptLen()
+	x = x % tWidth
+
+	if o.markStart > 0 {
+		o.buf.SetStyle(o.markStart, o.markEnd, "4")
+	}
+
+	lineCnt := o.buf.CursorLineCount()
+	buf := bytes.NewBuffer(nil)
+	buf.Write(bytes.Repeat([]byte("\n"), lineCnt))
+	buf.WriteString("\033[J")
+	if o.state == searchStateFailing {
+		buf.WriteString("failing ")
+	}
+	if o.dir == searchDirectionBackward {
+		buf.WriteString("bck")
+	} else if o.dir == searchDirectionForward {
+		buf.WriteString("fwd")
+	}
+	buf.WriteString("-i-search: ")
+	buf.WriteString(string(o.data))         // keyword
+	buf.WriteString("\033[4m \033[0m")      // _
+	fmt.Fprintf(buf, "\r\033[%dA", lineCnt) // move prev
+	if x > 0 {
+		fmt.Fprintf(buf, "\033[%dC", x) // move forward
+	}
+	o.w.Write(buf.Bytes())
+}
+
+func (o *opSearch) RefreshIfNeeded() {
+	o.mutex.Lock()
+	defer o.mutex.Unlock()
+
+	if o.inMode {
+		o.searchRefresh(-1)
+	}
+}

vendor/github.com/ergochat/readline/terminal.go

@@ -0,0 +1,490 @@
+package readline
+
+import (
+	"bufio"
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+	"strconv"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"github.com/ergochat/readline/internal/ansi"
+	"github.com/ergochat/readline/internal/platform"
+)
+
+const (
+	// see waitForDSR
+	dsrTimeout = 250 * time.Millisecond
+
+	maxAnsiLen = 32
+
+	// how many non-CPR reads to buffer while waiting for a CPR response
+	maxCPRBufferLen = 128 * 1024
+)
+
+var (
+	deadlineExceeded = errors.New("deadline exceeded")
+	concurrentReads  = errors.New("concurrent read operations detected")
+	invalidCPR       = errors.New("invalid CPR response")
+)
+
+/*
+terminal manages terminal input. The design constraints here are somewhat complex:
+
+1. Calls to (*Instance).Readline() must always be preemptible by (*Instance).Close.
+   This could be handled at the Operation layer instead; however, it's cleaner
+   to provide an API in terminal itself that can interrupt attempts to read.
+2. In between calls to Readline(), or *after* a call to (*Instance).Close(),
+   stdin must be available for code outside of this library to read from. The
+   problem is that reads from stdin in Go are not preemptible (see, for example,
+   https://github.com/golang/go/issues/24842 ). In the worst case, an
+   interrupted read will leave (*terminal).ioloop() running, and it will
+   consume one more user keystroke before it exits. However, it is a design goal
+   to read as little as possible at a time.
+3. We have to handle the DSR ("device status report") query and the
+   CPR ("cursor position report") response:
+   https://vt100.net/docs/vt510-rm/DSR-CPR.html
+   This involves writing an ANSI escape sequence to stdout, then waiting
+   for the terminal to asynchronously write an ANSI escape sequence to stdin.
+   We have to pick this value out of the stream and process it without
+   disrupting the handling of actual user input. Moreover, concurrent Close()
+   while a CPR query is in flight should ensure (if possible) that the
+   response is actually read; otherwise the response may be printed to the
+   screen, disrupting the user experience.
+
+Accordingly, the concurrency design is as follows:
+
+1. ioloop() runs asynchronously. It operates in lockstep with the read methods:
+   each synchronous receive from kickChan is matched with a synchronous send to
+   outChan. It does blocking reads from stdin, reading as little as possible at
+   a time, and passing the results back over outChan.
+2. The read methods ("internal public API") GetRune() and GetCursorPosition()
+   are not concurrency-safe and must be called in serial. They are backed by
+   readFromStdin, which wakes ioloop() if necessary and waits for a response.
+   If GetCursorPosition() reads non-CPR data, it will buffer it for GetRune()
+   to read later.
+3. Close() can be called asynchronously. It interrupts ioloop() (unless ioloop()
+   is actually reading from stdin, in which case it interrupts it after the next
+   keystroke), and also interrupts any in-progress GetRune() call. If
+   GetCursorPosition() is in progress, it tries to wait until the CPR response
+   has been received. It is idempotent and can be called multiple times.
+*/
+
+type terminal struct {
+	cfg        atomic.Pointer[Config]
+	dimensions atomic.Pointer[termDimensions]
+	closeOnce  sync.Once
+	closeErr   error
+	outChan    chan readResult
+	kickChan   chan struct{}
+	stopChan   chan struct{}
+	buffer     []rune // actual input that we saw while waiting for the CPR
+	inFlight   bool   // tracks whether we initiated a read and then gave up waiting
+	sleeping   int32
+
+	// asynchronously receive DSR messages from the terminal,
+	// ensuring at most one query is in flight at a time
+	dsrLock sync.Mutex
+	dsrDone chan struct{} // nil if there is no DSR query in flight
+}
+
+// termDimensions stores the terminal width and height (-1 means unknown)
+type termDimensions struct {
+	width  int
+	height int
+}
+
+type cursorPosition struct {
+	row int
+	col int
+}
+
+// readResult represents the result of a single "read operation" from the
+// perspective of terminal. it may be a pure no-op. the consumer needs to
+// read again if it didn't get what it wanted
+type readResult struct {
+	r  rune
+	ok bool // is `r` valid user input? if not, we may need to read again
+	// other data that can be conveyed in a single read operation;
+	// currently only the CPR:
+	pos *cursorPosition
+}
+
+func newTerminal(cfg *Config) (*terminal, error) {
+	if cfg.isInteractive {
+		if ansiErr := ansi.EnableANSI(); ansiErr != nil {
+			return nil, fmt.Errorf("Could not enable ANSI escapes: %w", ansiErr)
+		}
+	}
+	t := &terminal{
+		kickChan: make(chan struct{}),
+		outChan:  make(chan readResult),
+		stopChan: make(chan struct{}),
+	}
+	t.SetConfig(cfg)
+	// Get and cache the current terminal size.
+	t.OnSizeChange()
+
+	go t.ioloop()
+	return t, nil
+}
+
+// SleepToResume will sleep myself, and return only if I'm resumed.
+func (t *terminal) SleepToResume() {
+	if !atomic.CompareAndSwapInt32(&t.sleeping, 0, 1) {
+		return
+	}
+	defer atomic.StoreInt32(&t.sleeping, 0)
+
+	t.ExitRawMode()
+	platform.SuspendProcess()
+	t.EnterRawMode()
+}
+
+func (t *terminal) EnterRawMode() (err error) {
+	return t.GetConfig().FuncMakeRaw()
+}
+
+func (t *terminal) ExitRawMode() (err error) {
+	return t.GetConfig().FuncExitRaw()
+}
+
+func (t *terminal) Write(b []byte) (int, error) {
+	return t.GetConfig().Stdout.Write(b)
+}
+
+// getOffset sends a DSR query to get the current offset, then blocks
+// until the query returns.
+func (t *terminal) GetCursorPosition(deadline chan struct{}) (cursorPosition, error) {
+	// ensure there is no in-flight query, set up a waiter
+	ok := func() (ok bool) {
+		t.dsrLock.Lock()
+		defer t.dsrLock.Unlock()
+		if t.dsrDone == nil {
+			t.dsrDone = make(chan struct{})
+			ok = true
+		}
+		return
+	}()
+
+	if !ok {
+		return cursorPosition{-1, -1}, concurrentReads
+	}
+
+	defer func() {
+		t.dsrLock.Lock()
+		defer t.dsrLock.Unlock()
+		close(t.dsrDone)
+		t.dsrDone = nil
+	}()
+
+	// send the DSR Cursor Position Report request to terminal stdout:
+	// https://vt100.net/docs/vt510-rm/DSR-CPR.html
+	_, err := t.Write([]byte("\x1b[6n"))
+	if err != nil {
+		return cursorPosition{-1, -1}, err
+	}
+
+	for {
+		result, err := t.readFromStdin(deadline)
+		if err != nil {
+			return cursorPosition{-1, -1}, err
+		}
+		if result.ok {
+			// non-CPR input, save it to be read later:
+			t.buffer = append(t.buffer, result.r)
+			if len(t.buffer) > maxCPRBufferLen {
+				panic("did not receive DSR CPR response")
+			}
+		}
+		if result.pos != nil {
+			return *result.pos, nil
+		}
+	}
+}
+
+// waitForDSR waits for any in-flight DSR query to complete. this prevents
+// garbage from being written to the terminal when Close() interrupts an
+// in-flight query.
+func (t *terminal) waitForDSR() {
+	t.dsrLock.Lock()
+	dsrDone := t.dsrDone
+	t.dsrLock.Unlock()
+	if dsrDone != nil {
+		// tradeoffs: if the timeout is too high, we risk slowing down Close();
+		// if it's too low, we risk writing the CPR to the terminal, which is bad UX,
+		// but neither of these outcomes is catastrophic
+		timer := time.NewTimer(dsrTimeout)
+		select {
+		case <-dsrDone:
+		case <-timer.C:
+		}
+		timer.Stop()
+	}
+}
+
+func (t *terminal) GetRune(deadline chan struct{}) (rune, error) {
+	if len(t.buffer) > 0 {
+		result := t.buffer[0]
+		t.buffer = t.buffer[1:]
+		return result, nil
+	}
+	return t.getRuneFromStdin(deadline)
+}
+
+func (t *terminal) getRuneFromStdin(deadline chan struct{}) (rune, error) {
+	for {
+		result, err := t.readFromStdin(deadline)
+		if err != nil {
+			return 0, err
+		} else if result.ok {
+			return result.r, nil
+		} // else: CPR or something else we didn't understand, read again
+	}
+}
+
+func (t *terminal) readFromStdin(deadline chan struct{}) (result readResult, err error) {
+	// we may have sent a kick previously and given up on the response;
+	// if so, don't kick again (we will try again to read the pending response)
+	if !t.inFlight {
+		select {
+		case t.kickChan <- struct{}{}:
+			t.inFlight = true
+		case <-t.stopChan:
+			return result, io.EOF
+		case <-deadline:
+			return result, deadlineExceeded
+		}
+	}
+
+	select {
+	case result = <-t.outChan:
+		t.inFlight = false
+		return result, nil
+	case <-t.stopChan:
+		return result, io.EOF
+	case <-deadline:
+		return result, deadlineExceeded
+	}
+}
+
+func (t *terminal) ioloop() {
+	// ensure close if we get an error from stdio
+	defer t.Close()
+
+	buf := bufio.NewReader(t.GetConfig().Stdin)
+	var ansiBuf bytes.Buffer
+
+	for {
+		select {
+		case <-t.kickChan:
+		case <-t.stopChan:
+			return
+		}
+
+		r, _, err := buf.ReadRune()
+		if err != nil {
+			return
+		}
+
+		var result readResult
+		if r == '\x1b' {
+			// we're starting an ANSI escape sequence:
+			// keep reading until we reach the end of the sequence
+			result, err = t.consumeANSIEscape(buf, &ansiBuf)
+			if err != nil {
+				return
+			}
+		} else {
+			result = readResult{r: r, ok: true}
+		}
+
+		select {
+		case t.outChan <- result:
+		case <-t.stopChan:
+			return
+		}
+	}
+}
+
+func (t *terminal) consumeANSIEscape(buf *bufio.Reader, ansiBuf *bytes.Buffer) (result readResult, err error) {
+	ansiBuf.Reset()
+	initial, _, err := buf.ReadRune()
+	if err != nil {
+		return
+	}
+	// we already read one \x1b. this can indicate either the start of an ANSI
+	// escape sequence, or a keychord with Alt (e.g. Alt+f produces `\x1bf` in
+	// a typical xterm).
+	switch initial {
+	case 'f':
+		// Alt-f in xterm, or Option+RightArrow in iTerm2 with "Natural text editing"
+		return readResult{r: MetaForward, ok: true}, nil // Alt-f
+	case 'b':
+		// Alt-b in xterm, or Option+LeftArrow in iTerm2 with "Natural text editing"
+		return readResult{r: MetaBackward, ok: true}, nil // Alt-b
+	case '[', 'O':
+		// this is a real ANSI escape sequence, read the rest of the sequence below:
+	case '\x1b':
+		// Alt plus a real ANSI escape sequence. Handle this specially since
+		// right now the only cases we want to handle are the arrow keys:
+		return consumeAltSequence(buf)
+	default:
+		return // invalid, ignore
+	}
+
+	// data consists of ; and 0-9 , anything else terminates the sequence
+	var type_ rune
+	for {
+		r, _, err := buf.ReadRune()
+		if err != nil {
+			return result, err
+		}
+		if r == ';' || ('0' <= r && r <= '9') {
+			ansiBuf.WriteRune(r)
+		} else {
+			type_ = r
+			break
+		}
+	}
+
+	var r rune
+	switch type_ {
+	case 'R':
+		if initial == '[' {
+			// DSR CPR response; if we can't parse it, just ignore it
+			// (do not return an error here because that would stop ioloop())
+			if cpos, err := parseCPRResponse(ansiBuf.Bytes()); err == nil {
+				return readResult{r: 0, ok: false, pos: &cpos}, nil
+			}
+		}
+	case 'D':
+		if altModifierEnabled(ansiBuf.Bytes()) {
+			r = MetaBackward
+		} else {
+			r = CharBackward
+		}
+	case 'C':
+		if altModifierEnabled(ansiBuf.Bytes()) {
+			r = MetaForward
+		} else {
+			r = CharForward
+		}
+	case 'A':
+		r = CharPrev
+	case 'B':
+		r = CharNext
+	case 'H':
+		r = CharLineStart
+	case 'F':
+		r = CharLineEnd
+	case '~':
+		if initial == '[' {
+			switch string(ansiBuf.Bytes()) {
+			case "3":
+				r = MetaDeleteKey // this is the key typically labeled "Delete"
+			case "1", "7":
+				r = CharLineStart // "Home" key
+			case "4", "8":
+				r = CharLineEnd // "End" key
+			}
+		}
+	case 'Z':
+		if initial == '[' {
+			r = MetaShiftTab
+		}
+	}
+
+	if r != 0 {
+		return readResult{r: r, ok: true}, nil
+	}
+	return // default: no interpretable rune value
+}
+
+func consumeAltSequence(buf *bufio.Reader) (result readResult, err error) {
+	initial, _, err := buf.ReadRune()
+	if err != nil {
+		return
+	}
+	if initial != '[' {
+		return
+	}
+	second, _, err := buf.ReadRune()
+	if err != nil {
+		return
+	}
+	switch second {
+	case 'D':
+		return readResult{r: MetaBackward, ok: true}, nil
+	case 'C':
+		return readResult{r: MetaForward, ok: true}, nil
+	default:
+		return
+	}
+}
+
+func altModifierEnabled(payload []byte) bool {
+	// https://www.xfree86.org/current/ctlseqs.html ; modifier keycodes
+	// go after the semicolon, e.g. Alt-LeftArrow is `\x1b[1;3D` in VTE
+	// terminals, where 3 indicates Alt
+	if semicolonIdx := bytes.IndexByte(payload, ';'); semicolonIdx != -1 {
+		if string(payload[semicolonIdx+1:]) == "3" {
+			return true
+		}
+	}
+	return false
+}
+
+func parseCPRResponse(payload []byte) (cursorPosition, error) {
+	if semicolonIdx := bytes.IndexByte(payload, ';'); semicolonIdx != -1 {
+		if row, err := strconv.Atoi(string(payload[:semicolonIdx])); err == nil {
+			if col, err := strconv.Atoi(string(payload[semicolonIdx+1:])); err == nil {
+				return cursorPosition{row: row, col: col}, nil
+			}
+		}
+	}
+	return cursorPosition{-1, -1}, invalidCPR
+}
+
+func (t *terminal) Bell() {
+	t.Write([]byte{CharBell})
+}
+
+func (t *terminal) Close() error {
+	t.closeOnce.Do(func() {
+		t.waitForDSR()
+		close(t.stopChan)
+		// don't close outChan; outChan results should always be valid.
+		// instead we always select on both outChan and stopChan
+		t.closeErr = t.ExitRawMode()
+	})
+	return t.closeErr
+}
+
+func (t *terminal) SetConfig(c *Config) error {
+	t.cfg.Store(c)
+	return nil
+}
+
+func (t *terminal) GetConfig() *Config {
+	return t.cfg.Load()
+}
+
+// OnSizeChange gets the current terminal size and caches it
+func (t *terminal) OnSizeChange() {
+	cfg := t.GetConfig()
+	width, height := cfg.FuncGetSize()
+	t.dimensions.Store(&termDimensions{
+		width:  width,
+		height: height,
+	})
+}
+
+// GetWidthHeight returns the cached width, height values from the terminal
+func (t *terminal) GetWidthHeight() (width, height int) {
+	dimensions := t.dimensions.Load()
+	return dimensions.width, dimensions.height
+}

vendor/github.com/ergochat/readline/undo.go

@@ -0,0 +1,68 @@
+package readline
+
+import (
+	"github.com/ergochat/readline/internal/ringbuf"
+)
+
+type undoEntry struct {
+	pos int
+	buf []rune
+}
+
+// nil receiver is a valid no-op object
+type opUndo struct {
+	op    *operation
+	stack ringbuf.Buffer[undoEntry]
+}
+
+func newOpUndo(op *operation) *opUndo {
+	o := &opUndo{op: op}
+	o.stack.Initialize(32, 64)
+	o.init()
+	return o
+}
+
+func (o *opUndo) add() {
+	if o == nil {
+		return
+	}
+
+	top, success := o.stack.Pop()
+	buf, pos, changed := o.op.buf.CopyForUndo(top.buf) // if !success, top.buf is nil
+	newEntry := undoEntry{pos: pos, buf: buf}
+	if !success {
+		o.stack.Add(newEntry)
+	} else if !changed {
+		o.stack.Add(newEntry) // update cursor position
+	} else {
+		o.stack.Add(top)
+		o.stack.Add(newEntry)
+	}
+}
+
+func (o *opUndo) undo() {
+	if o == nil {
+		return
+	}
+
+	top, success := o.stack.Pop()
+	if !success {
+		return
+	}
+	o.op.buf.Restore(top.buf, top.pos)
+	o.op.buf.Refresh(nil)
+}
+
+func (o *opUndo) init() {
+	if o == nil {
+		return
+	}
+
+	buf, pos, _ := o.op.buf.CopyForUndo(nil)
+	initialEntry := undoEntry{
+		pos: pos,
+		buf: buf,
+	}
+	o.stack.Clear()
+	o.stack.Add(initialEntry)
+}

vendor/github.com/ergochat/readline/utils.go

@@ -0,0 +1,101 @@
+package readline
+
+import (
+	"container/list"
+	"fmt"
+	"io"
+	"os"
+	"sync"
+	"syscall"
+
+	"github.com/ergochat/readline/internal/term"
+)
+
+const (
+	CharLineStart = 1
+	CharBackward  = 2
+	CharInterrupt = 3
+	CharEOT       = 4
+	CharLineEnd   = 5
+	CharForward   = 6
+	CharBell      = 7
+	CharCtrlH     = 8
+	CharTab       = 9
+	CharCtrlJ     = 10
+	CharKill      = 11
+	CharCtrlL     = 12
+	CharEnter     = 13
+	CharNext      = 14
+	CharPrev      = 16
+	CharBckSearch = 18
+	CharFwdSearch = 19
+	CharTranspose = 20
+	CharCtrlU     = 21
+	CharCtrlW     = 23
+	CharCtrlY     = 25
+	CharCtrlZ     = 26
+	CharEsc       = 27
+	CharCtrl_     = 31
+	CharO         = 79
+	CharEscapeEx  = 91
+	CharBackspace = 127
+)
+
+const (
+	MetaBackward rune = -iota - 1
+	MetaForward
+	MetaDelete
+	MetaBackspace
+	MetaTranspose
+	MetaShiftTab
+	MetaDeleteKey
+)
+
+type rawModeHandler struct {
+	sync.Mutex
+	state *term.State
+}
+
+func (r *rawModeHandler) Enter() (err error) {
+	r.Lock()
+	defer r.Unlock()
+	r.state, err = term.MakeRaw(int(syscall.Stdin))
+	return err
+}
+
+func (r *rawModeHandler) Exit() error {
+	r.Lock()
+	defer r.Unlock()
+	if r.state == nil {
+		return nil
+	}
+	err := term.Restore(int(syscall.Stdin), r.state)
+	if err == nil {
+		r.state = nil
+	}
+	return err
+}
+
+func clearScreen(w io.Writer) error {
+	_, err := w.Write([]byte("\x1b[H\x1b[J"))
+	return err
+}
+
+// -----------------------------------------------------------------------------
+
+// print a linked list to Debug()
+func debugList(l *list.List) {
+	idx := 0
+	for e := l.Front(); e != nil; e = e.Next() {
+		debugPrint("%d %+v", idx, e.Value)
+		idx++
+	}
+}
+
+// append log info to another file
+func debugPrint(fmtStr string, o ...interface{}) {
+	f, _ := os.OpenFile("debug.tmp", os.O_RDWR|os.O_CREATE|os.O_APPEND, 0644)
+	fmt.Fprintf(f, fmtStr, o...)
+	fmt.Fprintln(f)
+	f.Close()
+}

vendor/github.com/ergochat/readline/vim.go

@@ -0,0 +1,162 @@
+package readline
+
+const (
+	vim_NORMAL = iota
+	vim_INSERT
+	vim_VISUAL
+)
+
+type opVim struct {
+	op      *operation
+	vimMode int
+}
+
+func newVimMode(op *operation) *opVim {
+	ov := &opVim{
+		op:      op,
+		vimMode: vim_INSERT,
+	}
+	return ov
+}
+
+func (o *opVim) IsEnableVimMode() bool {
+	return o.op.GetConfig().VimMode
+}
+
+func (o *opVim) handleVimNormalMovement(r rune, readNext func() rune) (t rune, handled bool) {
+	rb := o.op.buf
+	handled = true
+	switch r {
+	case 'h':
+		t = CharBackward
+	case 'j':
+		t = CharNext
+	case 'k':
+		t = CharPrev
+	case 'l':
+		t = CharForward
+	case '0', '^':
+		rb.MoveToLineStart()
+	case '$':
+		rb.MoveToLineEnd()
+	case 'x':
+		rb.Delete()
+		if rb.IsCursorInEnd() {
+			rb.MoveBackward()
+		}
+	case 'r':
+		rb.Replace(readNext())
+	case 'd':
+		next := readNext()
+		switch next {
+		case 'd':
+			rb.Erase()
+		case 'w':
+			rb.DeleteWord()
+		case 'h':
+			rb.Backspace()
+		case 'l':
+			rb.Delete()
+		}
+	case 'p':
+		rb.Yank()
+	case 'b', 'B':
+		rb.MoveToPrevWord()
+	case 'w', 'W':
+		rb.MoveToNextWord()
+	case 'e', 'E':
+		rb.MoveToEndWord()
+	case 'f', 'F', 't', 'T':
+		next := readNext()
+		prevChar := r == 't' || r == 'T'
+		reverse := r == 'F' || r == 'T'
+		switch next {
+		case CharEsc:
+		default:
+			rb.MoveTo(next, prevChar, reverse)
+		}
+	default:
+		return r, false
+	}
+	return t, true
+}
+
+func (o *opVim) handleVimNormalEnterInsert(r rune, readNext func() rune) (t rune, handled bool) {
+	rb := o.op.buf
+	handled = true
+	switch r {
+	case 'i':
+	case 'I':
+		rb.MoveToLineStart()
+	case 'a':
+		rb.MoveForward()
+	case 'A':
+		rb.MoveToLineEnd()
+	case 's':
+		rb.Delete()
+	case 'S':
+		rb.Erase()
+	case 'c':
+		next := readNext()
+		switch next {
+		case 'c':
+			rb.Erase()
+		case 'w':
+			rb.DeleteWord()
+		case 'h':
+			rb.Backspace()
+		case 'l':
+			rb.Delete()
+		}
+	default:
+		return r, false
+	}
+
+	o.EnterVimInsertMode()
+	return
+}
+
+func (o *opVim) HandleVimNormal(r rune, readNext func() rune) (t rune) {
+	switch r {
+	case CharEnter, CharInterrupt:
+		o.vimMode = vim_INSERT // ???
+		return r
+	}
+
+	if r, handled := o.handleVimNormalMovement(r, readNext); handled {
+		return r
+	}
+
+	if r, handled := o.handleVimNormalEnterInsert(r, readNext); handled {
+		return r
+	}
+
+	// invalid operation
+	o.op.t.Bell()
+	return 0
+}
+
+func (o *opVim) EnterVimInsertMode() {
+	o.vimMode = vim_INSERT
+}
+
+func (o *opVim) ExitVimInsertMode() {
+	o.vimMode = vim_NORMAL
+}
+
+func (o *opVim) HandleVim(r rune, readNext func() rune) rune {
+	if o.vimMode == vim_NORMAL {
+		return o.HandleVimNormal(r, readNext)
+	}
+	if r == CharEsc {
+		o.ExitVimInsertMode()
+		return 0
+	}
+
+	switch o.vimMode {
+	case vim_INSERT:
+		return r
+	case vim_VISUAL:
+	}
+	return r
+}

vendor/golang.org/x/sys/plan9/asm.s

@@ -0,0 +1,8 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+TEXT ·use(SB),NOSPLIT,$0
+	RET

vendor/golang.org/x/sys/plan9/asm_plan9_386.s

@@ -0,0 +1,30 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+//
+// System call support for 386, Plan 9
+//
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT	·Syscall(SB),NOSPLIT,$0-32
+	JMP	syscall·Syscall(SB)
+
+TEXT	·Syscall6(SB),NOSPLIT,$0-44
+	JMP	syscall·Syscall6(SB)
+
+TEXT ·RawSyscall(SB),NOSPLIT,$0-28
+	JMP	syscall·RawSyscall(SB)
+
+TEXT ·RawSyscall6(SB),NOSPLIT,$0-40
+	JMP	syscall·RawSyscall6(SB)
+
+TEXT ·seek(SB),NOSPLIT,$0-36
+	JMP	syscall·seek(SB)
+
+TEXT ·exit(SB),NOSPLIT,$4-4
+	JMP	syscall·exit(SB)

vendor/golang.org/x/sys/plan9/asm_plan9_amd64.s

@@ -0,0 +1,30 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+//
+// System call support for amd64, Plan 9
+//
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT	·Syscall(SB),NOSPLIT,$0-64
+	JMP	syscall·Syscall(SB)
+
+TEXT	·Syscall6(SB),NOSPLIT,$0-88
+	JMP	syscall·Syscall6(SB)
+
+TEXT ·RawSyscall(SB),NOSPLIT,$0-56
+	JMP	syscall·RawSyscall(SB)
+
+TEXT	·RawSyscall6(SB),NOSPLIT,$0-80
+	JMP	syscall·RawSyscall6(SB)
+
+TEXT ·seek(SB),NOSPLIT,$0-56
+	JMP	syscall·seek(SB)
+
+TEXT ·exit(SB),NOSPLIT,$8-8
+	JMP	syscall·exit(SB)

vendor/golang.org/x/sys/plan9/asm_plan9_arm.s

@@ -0,0 +1,25 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// System call support for plan9 on arm
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT ·Syscall(SB),NOSPLIT,$0-32
+	JMP	syscall·Syscall(SB)
+
+TEXT ·Syscall6(SB),NOSPLIT,$0-44
+	JMP	syscall·Syscall6(SB)
+
+TEXT ·RawSyscall(SB),NOSPLIT,$0-28
+	JMP	syscall·RawSyscall(SB)
+
+TEXT ·RawSyscall6(SB),NOSPLIT,$0-40
+	JMP	syscall·RawSyscall6(SB)
+
+TEXT ·seek(SB),NOSPLIT,$0-36
+	JMP	syscall·exit(SB)

vendor/golang.org/x/sys/plan9/const_plan9.go

@@ -0,0 +1,70 @@
+package plan9
+
+// Plan 9 Constants
+
+// Open modes
+const (
+	O_RDONLY  = 0
+	O_WRONLY  = 1
+	O_RDWR    = 2
+	O_TRUNC   = 16
+	O_CLOEXEC = 32
+	O_EXCL    = 0x1000
+)
+
+// Rfork flags
+const (
+	RFNAMEG  = 1 << 0
+	RFENVG   = 1 << 1
+	RFFDG    = 1 << 2
+	RFNOTEG  = 1 << 3
+	RFPROC   = 1 << 4
+	RFMEM    = 1 << 5
+	RFNOWAIT = 1 << 6
+	RFCNAMEG = 1 << 10
+	RFCENVG  = 1 << 11
+	RFCFDG   = 1 << 12
+	RFREND   = 1 << 13
+	RFNOMNT  = 1 << 14
+)
+
+// Qid.Type bits
+const (
+	QTDIR    = 0x80
+	QTAPPEND = 0x40
+	QTEXCL   = 0x20
+	QTMOUNT  = 0x10
+	QTAUTH   = 0x08
+	QTTMP    = 0x04
+	QTFILE   = 0x00
+)
+
+// Dir.Mode bits
+const (
+	DMDIR    = 0x80000000
+	DMAPPEND = 0x40000000
+	DMEXCL   = 0x20000000
+	DMMOUNT  = 0x10000000
+	DMAUTH   = 0x08000000
+	DMTMP    = 0x04000000
+	DMREAD   = 0x4
+	DMWRITE  = 0x2
+	DMEXEC   = 0x1
+)
+
+const (
+	STATMAX    = 65535
+	ERRMAX     = 128
+	STATFIXLEN = 49
+)
+
+// Mount and bind flags
+const (
+	MREPL   = 0x0000
+	MBEFORE = 0x0001
+	MAFTER  = 0x0002
+	MORDER  = 0x0003
+	MCREATE = 0x0004
+	MCACHE  = 0x0010
+	MMASK   = 0x0017
+)

vendor/golang.org/x/sys/plan9/dir_plan9.go

@@ -0,0 +1,212 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Plan 9 directory marshalling. See intro(5).
+
+package plan9
+
+import "errors"
+
+var (
+	ErrShortStat = errors.New("stat buffer too short")
+	ErrBadStat   = errors.New("malformed stat buffer")
+	ErrBadName   = errors.New("bad character in file name")
+)
+
+// A Qid represents a 9P server's unique identification for a file.
+type Qid struct {
+	Path uint64 // the file server's unique identification for the file
+	Vers uint32 // version number for given Path
+	Type uint8  // the type of the file (plan9.QTDIR for example)
+}
+
+// A Dir contains the metadata for a file.
+type Dir struct {
+	// system-modified data
+	Type uint16 // server type
+	Dev  uint32 // server subtype
+
+	// file data
+	Qid    Qid    // unique id from server
+	Mode   uint32 // permissions
+	Atime  uint32 // last read time
+	Mtime  uint32 // last write time
+	Length int64  // file length
+	Name   string // last element of path
+	Uid    string // owner name
+	Gid    string // group name
+	Muid   string // last modifier name
+}
+
+var nullDir = Dir{
+	Type: ^uint16(0),
+	Dev:  ^uint32(0),
+	Qid: Qid{
+		Path: ^uint64(0),
+		Vers: ^uint32(0),
+		Type: ^uint8(0),
+	},
+	Mode:   ^uint32(0),
+	Atime:  ^uint32(0),
+	Mtime:  ^uint32(0),
+	Length: ^int64(0),
+}
+
+// Null assigns special "don't touch" values to members of d to
+// avoid modifying them during plan9.Wstat.
+func (d *Dir) Null() { *d = nullDir }
+
+// Marshal encodes a 9P stat message corresponding to d into b
+//
+// If there isn't enough space in b for a stat message, ErrShortStat is returned.
+func (d *Dir) Marshal(b []byte) (n int, err error) {
+	n = STATFIXLEN + len(d.Name) + len(d.Uid) + len(d.Gid) + len(d.Muid)
+	if n > len(b) {
+		return n, ErrShortStat
+	}
+
+	for _, c := range d.Name {
+		if c == '/' {
+			return n, ErrBadName
+		}
+	}
+
+	b = pbit16(b, uint16(n)-2)
+	b = pbit16(b, d.Type)
+	b = pbit32(b, d.Dev)
+	b = pbit8(b, d.Qid.Type)
+	b = pbit32(b, d.Qid.Vers)
+	b = pbit64(b, d.Qid.Path)
+	b = pbit32(b, d.Mode)
+	b = pbit32(b, d.Atime)
+	b = pbit32(b, d.Mtime)
+	b = pbit64(b, uint64(d.Length))
+	b = pstring(b, d.Name)
+	b = pstring(b, d.Uid)
+	b = pstring(b, d.Gid)
+	b = pstring(b, d.Muid)
+
+	return n, nil
+}
+
+// UnmarshalDir decodes a single 9P stat message from b and returns the resulting Dir.
+//
+// If b is too small to hold a valid stat message, ErrShortStat is returned.
+//
+// If the stat message itself is invalid, ErrBadStat is returned.
+func UnmarshalDir(b []byte) (*Dir, error) {
+	if len(b) < STATFIXLEN {
+		return nil, ErrShortStat
+	}
+	size, buf := gbit16(b)
+	if len(b) != int(size)+2 {
+		return nil, ErrBadStat
+	}
+	b = buf
+
+	var d Dir
+	d.Type, b = gbit16(b)
+	d.Dev, b = gbit32(b)
+	d.Qid.Type, b = gbit8(b)
+	d.Qid.Vers, b = gbit32(b)
+	d.Qid.Path, b = gbit64(b)
+	d.Mode, b = gbit32(b)
+	d.Atime, b = gbit32(b)
+	d.Mtime, b = gbit32(b)
+
+	n, b := gbit64(b)
+	d.Length = int64(n)
+
+	var ok bool
+	if d.Name, b, ok = gstring(b); !ok {
+		return nil, ErrBadStat
+	}
+	if d.Uid, b, ok = gstring(b); !ok {
+		return nil, ErrBadStat
+	}
+	if d.Gid, b, ok = gstring(b); !ok {
+		return nil, ErrBadStat
+	}
+	if d.Muid, b, ok = gstring(b); !ok {
+		return nil, ErrBadStat
+	}
+
+	return &d, nil
+}
+
+// pbit8 copies the 8-bit number v to b and returns the remaining slice of b.
+func pbit8(b []byte, v uint8) []byte {
+	b[0] = byte(v)
+	return b[1:]
+}
+
+// pbit16 copies the 16-bit number v to b in little-endian order and returns the remaining slice of b.
+func pbit16(b []byte, v uint16) []byte {
+	b[0] = byte(v)
+	b[1] = byte(v >> 8)
+	return b[2:]
+}
+
+// pbit32 copies the 32-bit number v to b in little-endian order and returns the remaining slice of b.
+func pbit32(b []byte, v uint32) []byte {
+	b[0] = byte(v)
+	b[1] = byte(v >> 8)
+	b[2] = byte(v >> 16)
+	b[3] = byte(v >> 24)
+	return b[4:]
+}
+
+// pbit64 copies the 64-bit number v to b in little-endian order and returns the remaining slice of b.
+func pbit64(b []byte, v uint64) []byte {
+	b[0] = byte(v)
+	b[1] = byte(v >> 8)
+	b[2] = byte(v >> 16)
+	b[3] = byte(v >> 24)
+	b[4] = byte(v >> 32)
+	b[5] = byte(v >> 40)
+	b[6] = byte(v >> 48)
+	b[7] = byte(v >> 56)
+	return b[8:]
+}
+
+// pstring copies the string s to b, prepending it with a 16-bit length in little-endian order, and
+// returning the remaining slice of b..
+func pstring(b []byte, s string) []byte {
+	b = pbit16(b, uint16(len(s)))
+	n := copy(b, s)
+	return b[n:]
+}
+
+// gbit8 reads an 8-bit number from b and returns it with the remaining slice of b.
+func gbit8(b []byte) (uint8, []byte) {
+	return uint8(b[0]), b[1:]
+}
+
+// gbit16 reads a 16-bit number in little-endian order from b and returns it with the remaining slice of b.
+func gbit16(b []byte) (uint16, []byte) {
+	return uint16(b[0]) | uint16(b[1])<<8, b[2:]
+}
+
+// gbit32 reads a 32-bit number in little-endian order from b and returns it with the remaining slice of b.
+func gbit32(b []byte) (uint32, []byte) {
+	return uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24, b[4:]
+}
+
+// gbit64 reads a 64-bit number in little-endian order from b and returns it with the remaining slice of b.
+func gbit64(b []byte) (uint64, []byte) {
+	lo := uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24
+	hi := uint32(b[4]) | uint32(b[5])<<8 | uint32(b[6])<<16 | uint32(b[7])<<24
+	return uint64(lo) | uint64(hi)<<32, b[8:]
+}
+
+// gstring reads a string from b, prefixed with a 16-bit length in little-endian order.
+// It returns the string with the remaining slice of b and a boolean. If the length is
+// greater than the number of bytes in b, the boolean will be false.
+func gstring(b []byte) (string, []byte, bool) {
+	n, b := gbit16(b)
+	if int(n) > len(b) {
+		return "", b, false
+	}
+	return string(b[:n]), b[n:], true
+}

vendor/golang.org/x/sys/plan9/env_plan9.go

@@ -0,0 +1,31 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Plan 9 environment variables.
+
+package plan9
+
+import (
+	"syscall"
+)
+
+func Getenv(key string) (value string, found bool) {
+	return syscall.Getenv(key)
+}
+
+func Setenv(key, value string) error {
+	return syscall.Setenv(key, value)
+}
+
+func Clearenv() {
+	syscall.Clearenv()
+}
+
+func Environ() []string {
+	return syscall.Environ()
+}
+
+func Unsetenv(key string) error {
+	return syscall.Unsetenv(key)
+}

vendor/golang.org/x/sys/plan9/errors_plan9.go

@@ -0,0 +1,50 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package plan9
+
+import "syscall"
+
+// Constants
+const (
+	// Invented values to support what package os expects.
+	O_CREAT    = 0x02000
+	O_APPEND   = 0x00400
+	O_NOCTTY   = 0x00000
+	O_NONBLOCK = 0x00000
+	O_SYNC     = 0x00000
+	O_ASYNC    = 0x00000
+
+	S_IFMT   = 0x1f000
+	S_IFIFO  = 0x1000
+	S_IFCHR  = 0x2000
+	S_IFDIR  = 0x4000
+	S_IFBLK  = 0x6000
+	S_IFREG  = 0x8000
+	S_IFLNK  = 0xa000
+	S_IFSOCK = 0xc000
+)
+
+// Errors
+var (
+	EINVAL       = syscall.NewError("bad arg in system call")
+	ENOTDIR      = syscall.NewError("not a directory")
+	EISDIR       = syscall.NewError("file is a directory")
+	ENOENT       = syscall.NewError("file does not exist")
+	EEXIST       = syscall.NewError("file already exists")
+	EMFILE       = syscall.NewError("no free file descriptors")
+	EIO          = syscall.NewError("i/o error")
+	ENAMETOOLONG = syscall.NewError("file name too long")
+	EINTR        = syscall.NewError("interrupted")
+	EPERM        = syscall.NewError("permission denied")
+	EBUSY        = syscall.NewError("no free devices")
+	ETIMEDOUT    = syscall.NewError("connection timed out")
+	EPLAN9       = syscall.NewError("not supported by plan 9")
+
+	// The following errors do not correspond to any
+	// Plan 9 system messages. Invented to support
+	// what package os and others expect.
+	EACCES       = syscall.NewError("access permission denied")
+	EAFNOSUPPORT = syscall.NewError("address family not supported by protocol")
+)

vendor/golang.org/x/sys/plan9/mkall.sh

@@ -0,0 +1,150 @@
+#!/usr/bin/env bash
+# Copyright 2009 The Go Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file.
+
+# The plan9 package provides access to the raw system call
+# interface of the underlying operating system.  Porting Go to
+# a new architecture/operating system combination requires
+# some manual effort, though there are tools that automate
+# much of the process.  The auto-generated files have names
+# beginning with z.
+#
+# This script runs or (given -n) prints suggested commands to generate z files
+# for the current system.  Running those commands is not automatic.
+# This script is documentation more than anything else.
+#
+# * asm_${GOOS}_${GOARCH}.s
+#
+# This hand-written assembly file implements system call dispatch.
+# There are three entry points:
+#
+# 	func Syscall(trap, a1, a2, a3 uintptr) (r1, r2, err uintptr);
+# 	func Syscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr);
+# 	func RawSyscall(trap, a1, a2, a3 uintptr) (r1, r2, err uintptr);
+#
+# The first and second are the standard ones; they differ only in
+# how many arguments can be passed to the kernel.
+# The third is for low-level use by the ForkExec wrapper;
+# unlike the first two, it does not call into the scheduler to
+# let it know that a system call is running.
+#
+# * syscall_${GOOS}.go
+#
+# This hand-written Go file implements system calls that need
+# special handling and lists "//sys" comments giving prototypes
+# for ones that can be auto-generated.  Mksyscall reads those
+# comments to generate the stubs.
+#
+# * syscall_${GOOS}_${GOARCH}.go
+#
+# Same as syscall_${GOOS}.go except that it contains code specific
+# to ${GOOS} on one particular architecture.
+#
+# * types_${GOOS}.c
+#
+# This hand-written C file includes standard C headers and then
+# creates typedef or enum names beginning with a dollar sign
+# (use of $ in variable names is a gcc extension).  The hardest
+# part about preparing this file is figuring out which headers to
+# include and which symbols need to be #defined to get the
+# actual data structures that pass through to the kernel system calls.
+# Some C libraries present alternate versions for binary compatibility
+# and translate them on the way in and out of system calls, but
+# there is almost always a #define that can get the real ones.
+# See types_darwin.c and types_linux.c for examples.
+#
+# * zerror_${GOOS}_${GOARCH}.go
+#
+# This machine-generated file defines the system's error numbers,
+# error strings, and signal numbers.  The generator is "mkerrors.sh".
+# Usually no arguments are needed, but mkerrors.sh will pass its
+# arguments on to godefs.
+#
+# * zsyscall_${GOOS}_${GOARCH}.go
+#
+# Generated by mksyscall.pl; see syscall_${GOOS}.go above.
+#
+# * zsysnum_${GOOS}_${GOARCH}.go
+#
+# Generated by mksysnum_${GOOS}.
+#
+# * ztypes_${GOOS}_${GOARCH}.go
+#
+# Generated by godefs; see types_${GOOS}.c above.
+
+GOOSARCH="${GOOS}_${GOARCH}"
+
+# defaults
+mksyscall="go run mksyscall.go"
+mkerrors="./mkerrors.sh"
+zerrors="zerrors_$GOOSARCH.go"
+mksysctl=""
+zsysctl="zsysctl_$GOOSARCH.go"
+mksysnum=
+mktypes=
+run="sh"
+
+case "$1" in
+-syscalls)
+	for i in zsyscall*go
+	do
+		sed 1q $i | sed 's;^// ;;' | sh > _$i && gofmt < _$i > $i
+		rm _$i
+	done
+	exit 0
+	;;
+-n)
+	run="cat"
+	shift
+esac
+
+case "$#" in
+0)
+	;;
+*)
+	echo 'usage: mkall.sh [-n]' 1>&2
+	exit 2
+esac
+
+case "$GOOSARCH" in
+_* | *_ | _)
+	echo 'undefined $GOOS_$GOARCH:' "$GOOSARCH" 1>&2
+	exit 1
+	;;
+plan9_386)
+	mkerrors=
+	mksyscall="go run mksyscall.go -l32 -plan9 -tags plan9,386"
+	mksysnum="./mksysnum_plan9.sh /n/sources/plan9/sys/src/libc/9syscall/sys.h"
+	mktypes="XXX"
+	;;
+plan9_amd64)
+	mkerrors=
+	mksyscall="go run mksyscall.go -l32 -plan9 -tags plan9,amd64"
+	mksysnum="./mksysnum_plan9.sh /n/sources/plan9/sys/src/libc/9syscall/sys.h"
+	mktypes="XXX"
+	;;
+plan9_arm)
+	mkerrors=
+	mksyscall="go run mksyscall.go -l32 -plan9 -tags plan9,arm"
+	mksysnum="./mksysnum_plan9.sh /n/sources/plan9/sys/src/libc/9syscall/sys.h"
+	mktypes="XXX"
+	;;
+*)
+	echo 'unrecognized $GOOS_$GOARCH: ' "$GOOSARCH" 1>&2
+	exit 1
+	;;
+esac
+
+(
+	if [ -n "$mkerrors" ]; then echo "$mkerrors |gofmt >$zerrors"; fi
+	case "$GOOS" in
+	plan9)
+		syscall_goos="syscall_$GOOS.go"
+		if [ -n "$mksyscall" ]; then echo "$mksyscall $syscall_goos |gofmt >zsyscall_$GOOSARCH.go"; fi
+		;;
+	esac
+	if [ -n "$mksysctl" ]; then echo "$mksysctl |gofmt >$zsysctl"; fi
+	if [ -n "$mksysnum" ]; then echo "$mksysnum |gofmt >zsysnum_$GOOSARCH.go"; fi
+	if [ -n "$mktypes" ]; then echo "$mktypes types_$GOOS.go |gofmt >ztypes_$GOOSARCH.go"; fi
+) | $run

vendor/golang.org/x/sys/plan9/mkerrors.sh

@@ -0,0 +1,246 @@
+#!/usr/bin/env bash
+# Copyright 2009 The Go Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file.
+
+# Generate Go code listing errors and other #defined constant
+# values (ENAMETOOLONG etc.), by asking the preprocessor
+# about the definitions.
+
+unset LANG
+export LC_ALL=C
+export LC_CTYPE=C
+
+CC=${CC:-gcc}
+
+uname=$(uname)
+
+includes='
+#include <sys/types.h>
+#include <sys/file.h>
+#include <fcntl.h>
+#include <dirent.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netinet/ip.h>
+#include <netinet/ip6.h>
+#include <netinet/tcp.h>
+#include <errno.h>
+#include <sys/signal.h>
+#include <signal.h>
+#include <sys/resource.h>
+'
+
+ccflags="$@"
+
+# Write go tool cgo -godefs input.
+(
+	echo package plan9
+	echo
+	echo '/*'
+	indirect="includes_$(uname)"
+	echo "${!indirect} $includes"
+	echo '*/'
+	echo 'import "C"'
+	echo
+	echo 'const ('
+
+	# The gcc command line prints all the #defines
+	# it encounters while processing the input
+	echo "${!indirect} $includes" | $CC -x c - -E -dM $ccflags |
+	awk '
+		$1 != "#define" || $2 ~ /\(/ || $3 == "" {next}
+
+		$2 ~ /^E([ABCD]X|[BIS]P|[SD]I|S|FL)$/ {next}  # 386 registers
+		$2 ~ /^(SIGEV_|SIGSTKSZ|SIGRT(MIN|MAX))/ {next}
+		$2 ~ /^(SCM_SRCRT)$/ {next}
+		$2 ~ /^(MAP_FAILED)$/ {next}
+
+		$2 !~ /^ETH_/ &&
+		$2 !~ /^EPROC_/ &&
+		$2 !~ /^EQUIV_/ &&
+		$2 !~ /^EXPR_/ &&
+		$2 ~ /^E[A-Z0-9_]+$/ ||
+		$2 ~ /^B[0-9_]+$/ ||
+		$2 ~ /^V[A-Z0-9]+$/ ||
+		$2 ~ /^CS[A-Z0-9]/ ||
+		$2 ~ /^I(SIG|CANON|CRNL|EXTEN|MAXBEL|STRIP|UTF8)$/ ||
+		$2 ~ /^IGN/ ||
+		$2 ~ /^IX(ON|ANY|OFF)$/ ||
+		$2 ~ /^IN(LCR|PCK)$/ ||
+		$2 ~ /(^FLU?SH)|(FLU?SH$)/ ||
+		$2 ~ /^C(LOCAL|READ)$/ ||
+		$2 == "BRKINT" ||
+		$2 == "HUPCL" ||
+		$2 == "PENDIN" ||
+		$2 == "TOSTOP" ||
+		$2 ~ /^PAR/ ||
+		$2 ~ /^SIG[^_]/ ||
+		$2 ~ /^O[CNPFP][A-Z]+[^_][A-Z]+$/ ||
+		$2 ~ /^IN_/ ||
+		$2 ~ /^LOCK_(SH|EX|NB|UN)$/ ||
+		$2 ~ /^(AF|SOCK|SO|SOL|IPPROTO|IP|IPV6|ICMP6|TCP|EVFILT|NOTE|EV|SHUT|PROT|MAP|PACKET|MSG|SCM|MCL|DT|MADV|PR)_/ ||
+		$2 == "ICMPV6_FILTER" ||
+		$2 == "SOMAXCONN" ||
+		$2 == "NAME_MAX" ||
+		$2 == "IFNAMSIZ" ||
+		$2 ~ /^CTL_(MAXNAME|NET|QUERY)$/ ||
+		$2 ~ /^SYSCTL_VERS/ ||
+		$2 ~ /^(MS|MNT)_/ ||
+		$2 ~ /^TUN(SET|GET|ATTACH|DETACH)/ ||
+		$2 ~ /^(O|F|FD|NAME|S|PTRACE|PT)_/ ||
+		$2 ~ /^LINUX_REBOOT_CMD_/ ||
+		$2 ~ /^LINUX_REBOOT_MAGIC[12]$/ ||
+		$2 !~ "NLA_TYPE_MASK" &&
+		$2 ~ /^(NETLINK|NLM|NLMSG|NLA|IFA|IFAN|RT|RTCF|RTN|RTPROT|RTNH|ARPHRD|ETH_P)_/ ||
+		$2 ~ /^SIOC/ ||
+		$2 ~ /^TIOC/ ||
+		$2 !~ "RTF_BITS" &&
+		$2 ~ /^(IFF|IFT|NET_RT|RTM|RTF|RTV|RTA|RTAX)_/ ||
+		$2 ~ /^BIOC/ ||
+		$2 ~ /^RUSAGE_(SELF|CHILDREN|THREAD)/ ||
+		$2 ~ /^RLIMIT_(AS|CORE|CPU|DATA|FSIZE|NOFILE|STACK)|RLIM_INFINITY/ ||
+		$2 ~ /^PRIO_(PROCESS|PGRP|USER)/ ||
+		$2 ~ /^CLONE_[A-Z_]+/ ||
+		$2 !~ /^(BPF_TIMEVAL)$/ &&
+		$2 ~ /^(BPF|DLT)_/ ||
+		$2 !~ "WMESGLEN" &&
+		$2 ~ /^W[A-Z0-9]+$/ {printf("\t%s = C.%s\n", $2, $2)}
+		$2 ~ /^__WCOREFLAG$/ {next}
+		$2 ~ /^__W[A-Z0-9]+$/ {printf("\t%s = C.%s\n", substr($2,3), $2)}
+
+		{next}
+	' | sort
+
+	echo ')'
+) >_const.go
+
+# Pull out the error names for later.
+errors=$(
+	echo '#include <errno.h>' | $CC -x c - -E -dM $ccflags |
+	awk '$1=="#define" && $2 ~ /^E[A-Z0-9_]+$/ { print $2 }' |
+	sort
+)
+
+# Pull out the signal names for later.
+signals=$(
+	echo '#include <signal.h>' | $CC -x c - -E -dM $ccflags |
+	awk '$1=="#define" && $2 ~ /^SIG[A-Z0-9]+$/ { print $2 }' |
+	grep -v 'SIGSTKSIZE\|SIGSTKSZ\|SIGRT' |
+	sort
+)
+
+# Again, writing regexps to a file.
+echo '#include <errno.h>' | $CC -x c - -E -dM $ccflags |
+	awk '$1=="#define" && $2 ~ /^E[A-Z0-9_]+$/ { print "^\t" $2 "[ \t]*=" }' |
+	sort >_error.grep
+echo '#include <signal.h>' | $CC -x c - -E -dM $ccflags |
+	awk '$1=="#define" && $2 ~ /^SIG[A-Z0-9]+$/ { print "^\t" $2 "[ \t]*=" }' |
+	grep -v 'SIGSTKSIZE\|SIGSTKSZ\|SIGRT' |
+	sort >_signal.grep
+
+echo '// mkerrors.sh' "$@"
+echo '// Code generated by the command above; DO NOT EDIT.'
+echo
+go tool cgo -godefs -- "$@" _const.go >_error.out
+cat _error.out | grep -vf _error.grep | grep -vf _signal.grep
+echo
+echo '// Errors'
+echo 'const ('
+cat _error.out | grep -f _error.grep | sed 's/=\(.*\)/= Errno(\1)/'
+echo ')'
+
+echo
+echo '// Signals'
+echo 'const ('
+cat _error.out | grep -f _signal.grep | sed 's/=\(.*\)/= Signal(\1)/'
+echo ')'
+
+# Run C program to print error and syscall strings.
+(
+	echo -E "
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <ctype.h>
+#include <string.h>
+#include <signal.h>
+
+#define nelem(x) (sizeof(x)/sizeof((x)[0]))
+
+enum { A = 'A', Z = 'Z', a = 'a', z = 'z' }; // avoid need for single quotes below
+
+int errors[] = {
+"
+	for i in $errors
+	do
+		echo -E '	'$i,
+	done
+
+	echo -E "
+};
+
+int signals[] = {
+"
+	for i in $signals
+	do
+		echo -E '	'$i,
+	done
+
+	# Use -E because on some systems bash builtin interprets \n itself.
+	echo -E '
+};
+
+static int
+intcmp(const void *a, const void *b)
+{
+	return *(int*)a - *(int*)b;
+}
+
+int
+main(void)
+{
+	int i, j, e;
+	char buf[1024], *p;
+
+	printf("\n\n// Error table\n");
+	printf("var errors = [...]string {\n");
+	qsort(errors, nelem(errors), sizeof errors[0], intcmp);
+	for(i=0; i<nelem(errors); i++) {
+		e = errors[i];
+		if(i > 0 && errors[i-1] == e)
+			continue;
+		strcpy(buf, strerror(e));
+		// lowercase first letter: Bad -> bad, but STREAM -> STREAM.
+		if(A <= buf[0] && buf[0] <= Z && a <= buf[1] && buf[1] <= z)
+			buf[0] += a - A;
+		printf("\t%d: \"%s\",\n", e, buf);
+	}
+	printf("}\n\n");
+	
+	printf("\n\n// Signal table\n");
+	printf("var signals = [...]string {\n");
+	qsort(signals, nelem(signals), sizeof signals[0], intcmp);
+	for(i=0; i<nelem(signals); i++) {
+		e = signals[i];
+		if(i > 0 && signals[i-1] == e)
+			continue;
+		strcpy(buf, strsignal(e));
+		// lowercase first letter: Bad -> bad, but STREAM -> STREAM.
+		if(A <= buf[0] && buf[0] <= Z && a <= buf[1] && buf[1] <= z)
+			buf[0] += a - A;
+		// cut trailing : number.
+		p = strrchr(buf, ":"[0]);
+		if(p)
+			*p = '\0';
+		printf("\t%d: \"%s\",\n", e, buf);
+	}
+	printf("}\n\n");
+
+	return 0;
+}
+
+'
+) >_errors.c
+
+$CC $ccflags -o _errors _errors.c && $GORUN ./_errors && rm -f _errors.c _errors _const.go _error.grep _signal.grep _error.out

vendor/golang.org/x/sys/plan9/mksysnum_plan9.sh

@@ -0,0 +1,23 @@
+#!/bin/sh
+# Copyright 2009 The Go Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file.
+
+COMMAND="mksysnum_plan9.sh $@"
+
+cat <<EOF
+// $COMMAND
+// MACHINE GENERATED BY THE ABOVE COMMAND; DO NOT EDIT
+
+package plan9
+
+const(
+EOF
+
+SP='[ 	]' # space or tab
+sed "s/^#define${SP}\\([A-Z0-9_][A-Z0-9_]*\\)${SP}${SP}*\\([0-9][0-9]*\\)/SYS_\\1=\\2/g" \
+	< $1 | grep -v SYS__
+
+cat <<EOF
+)
+EOF

vendor/golang.org/x/sys/plan9/pwd_go15_plan9.go

@@ -0,0 +1,21 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build go1.5
+
+package plan9
+
+import "syscall"
+
+func fixwd() {
+	syscall.Fixwd()
+}
+
+func Getwd() (wd string, err error) {
+	return syscall.Getwd()
+}
+
+func Chdir(path string) error {
+	return syscall.Chdir(path)
+}

vendor/golang.org/x/sys/plan9/pwd_plan9.go

@@ -0,0 +1,23 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !go1.5
+
+package plan9
+
+func fixwd() {
+}
+
+func Getwd() (wd string, err error) {
+	fd, err := open(".", O_RDONLY)
+	if err != nil {
+		return "", err
+	}
+	defer Close(fd)
+	return Fd2path(fd)
+}
+
+func Chdir(path string) error {
+	return chdir(path)
+}

vendor/golang.org/x/sys/plan9/race.go

@@ -0,0 +1,30 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build plan9 && race
+
+package plan9
+
+import (
+	"runtime"
+	"unsafe"
+)
+
+const raceenabled = true
+
+func raceAcquire(addr unsafe.Pointer) {
+	runtime.RaceAcquire(addr)
+}
+
+func raceReleaseMerge(addr unsafe.Pointer) {
+	runtime.RaceReleaseMerge(addr)
+}
+
+func raceReadRange(addr unsafe.Pointer, len int) {
+	runtime.RaceReadRange(addr, len)
+}
+
+func raceWriteRange(addr unsafe.Pointer, len int) {
+	runtime.RaceWriteRange(addr, len)
+}

vendor/golang.org/x/sys/plan9/race0.go

@@ -0,0 +1,25 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build plan9 && !race
+
+package plan9
+
+import (
+	"unsafe"
+)
+
+const raceenabled = false
+
+func raceAcquire(addr unsafe.Pointer) {
+}
+
+func raceReleaseMerge(addr unsafe.Pointer) {
+}
+
+func raceReadRange(addr unsafe.Pointer, len int) {
+}
+
+func raceWriteRange(addr unsafe.Pointer, len int) {
+}

vendor/golang.org/x/sys/plan9/str.go

@@ -0,0 +1,22 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build plan9
+
+package plan9
+
+func itoa(val int) string { // do it here rather than with fmt to avoid dependency
+	if val < 0 {
+		return "-" + itoa(-val)
+	}
+	var buf [32]byte // big enough for int64
+	i := len(buf) - 1
+	for val >= 10 {
+		buf[i] = byte(val%10 + '0')
+		i--
+		val /= 10
+	}
+	buf[i] = byte(val + '0')
+	return string(buf[i:])
+}

vendor/golang.org/x/sys/plan9/syscall.go

@@ -0,0 +1,109 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build plan9
+
+// Package plan9 contains an interface to the low-level operating system
+// primitives. OS details vary depending on the underlying system, and
+// by default, godoc will display the OS-specific documentation for the current
+// system. If you want godoc to display documentation for another
+// system, set $GOOS and $GOARCH to the desired system. For example, if
+// you want to view documentation for freebsd/arm on linux/amd64, set $GOOS
+// to freebsd and $GOARCH to arm.
+//
+// The primary use of this package is inside other packages that provide a more
+// portable interface to the system, such as "os", "time" and "net".  Use
+// those packages rather than this one if you can.
+//
+// For details of the functions and data types in this package consult
+// the manuals for the appropriate operating system.
+//
+// These calls return err == nil to indicate success; otherwise
+// err represents an operating system error describing the failure and
+// holds a value of type syscall.ErrorString.
+package plan9 // import "golang.org/x/sys/plan9"
+
+import (
+	"bytes"
+	"strings"
+	"unsafe"
+)
+
+// ByteSliceFromString returns a NUL-terminated slice of bytes
+// containing the text of s. If s contains a NUL byte at any
+// location, it returns (nil, EINVAL).
+func ByteSliceFromString(s string) ([]byte, error) {
+	if strings.IndexByte(s, 0) != -1 {
+		return nil, EINVAL
+	}
+	a := make([]byte, len(s)+1)
+	copy(a, s)
+	return a, nil
+}
+
+// BytePtrFromString returns a pointer to a NUL-terminated array of
+// bytes containing the text of s. If s contains a NUL byte at any
+// location, it returns (nil, EINVAL).
+func BytePtrFromString(s string) (*byte, error) {
+	a, err := ByteSliceFromString(s)
+	if err != nil {
+		return nil, err
+	}
+	return &a[0], nil
+}
+
+// ByteSliceToString returns a string form of the text represented by the slice s, with a terminating NUL and any
+// bytes after the NUL removed.
+func ByteSliceToString(s []byte) string {
+	if i := bytes.IndexByte(s, 0); i != -1 {
+		s = s[:i]
+	}
+	return string(s)
+}
+
+// BytePtrToString takes a pointer to a sequence of text and returns the corresponding string.
+// If the pointer is nil, it returns the empty string. It assumes that the text sequence is terminated
+// at a zero byte; if the zero byte is not present, the program may crash.
+func BytePtrToString(p *byte) string {
+	if p == nil {
+		return ""
+	}
+	if *p == 0 {
+		return ""
+	}
+
+	// Find NUL terminator.
+	n := 0
+	for ptr := unsafe.Pointer(p); *(*byte)(ptr) != 0; n++ {
+		ptr = unsafe.Pointer(uintptr(ptr) + 1)
+	}
+
+	return string(unsafe.Slice(p, n))
+}
+
+// Single-word zero for use when we need a valid pointer to 0 bytes.
+// See mksyscall.pl.
+var _zero uintptr
+
+func (ts *Timespec) Unix() (sec int64, nsec int64) {
+	return int64(ts.Sec), int64(ts.Nsec)
+}
+
+func (tv *Timeval) Unix() (sec int64, nsec int64) {
+	return int64(tv.Sec), int64(tv.Usec) * 1000
+}
+
+func (ts *Timespec) Nano() int64 {
+	return int64(ts.Sec)*1e9 + int64(ts.Nsec)
+}
+
+func (tv *Timeval) Nano() int64 {
+	return int64(tv.Sec)*1e9 + int64(tv.Usec)*1000
+}
+
+// use is a no-op, but the compiler cannot see that it is.
+// Calling use(p) ensures that p is kept live until that point.
+//
+//go:noescape
+func use(p unsafe.Pointer)

vendor/golang.org/x/sys/plan9/syscall_plan9.go

@@ -0,0 +1,361 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Plan 9 system calls.
+// This file is compiled as ordinary Go code,
+// but it is also input to mksyscall,
+// which parses the //sys lines and generates system call stubs.
+// Note that sometimes we use a lowercase //sys name and
+// wrap it in our own nicer implementation.
+
+package plan9
+
+import (
+	"bytes"
+	"syscall"
+	"unsafe"
+)
+
+// A Note is a string describing a process note.
+// It implements the os.Signal interface.
+type Note string
+
+func (n Note) Signal() {}
+
+func (n Note) String() string {
+	return string(n)
+}
+
+var (
+	Stdin  = 0
+	Stdout = 1
+	Stderr = 2
+)
+
+// For testing: clients can set this flag to force
+// creation of IPv6 sockets to return EAFNOSUPPORT.
+var SocketDisableIPv6 bool
+
+func Syscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err syscall.ErrorString)
+func Syscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err syscall.ErrorString)
+func RawSyscall(trap, a1, a2, a3 uintptr) (r1, r2, err uintptr)
+func RawSyscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr)
+
+func atoi(b []byte) (n uint) {
+	n = 0
+	for i := 0; i < len(b); i++ {
+		n = n*10 + uint(b[i]-'0')
+	}
+	return
+}
+
+func cstring(s []byte) string {
+	i := bytes.IndexByte(s, 0)
+	if i == -1 {
+		i = len(s)
+	}
+	return string(s[:i])
+}
+
+func errstr() string {
+	var buf [ERRMAX]byte
+
+	RawSyscall(SYS_ERRSTR, uintptr(unsafe.Pointer(&buf[0])), uintptr(len(buf)), 0)
+
+	buf[len(buf)-1] = 0
+	return cstring(buf[:])
+}
+
+// Implemented in assembly to import from runtime.
+func exit(code int)
+
+func Exit(code int) { exit(code) }
+
+func readnum(path string) (uint, error) {
+	var b [12]byte
+
+	fd, e := Open(path, O_RDONLY)
+	if e != nil {
+		return 0, e
+	}
+	defer Close(fd)
+
+	n, e := Pread(fd, b[:], 0)
+
+	if e != nil {
+		return 0, e
+	}
+
+	m := 0
+	for ; m < n && b[m] == ' '; m++ {
+	}
+
+	return atoi(b[m : n-1]), nil
+}
+
+func Getpid() (pid int) {
+	n, _ := readnum("#c/pid")
+	return int(n)
+}
+
+func Getppid() (ppid int) {
+	n, _ := readnum("#c/ppid")
+	return int(n)
+}
+
+func Read(fd int, p []byte) (n int, err error) {
+	return Pread(fd, p, -1)
+}
+
+func Write(fd int, p []byte) (n int, err error) {
+	return Pwrite(fd, p, -1)
+}
+
+var ioSync int64
+
+//sys	fd2path(fd int, buf []byte) (err error)
+
+func Fd2path(fd int) (path string, err error) {
+	var buf [512]byte
+
+	e := fd2path(fd, buf[:])
+	if e != nil {
+		return "", e
+	}
+	return cstring(buf[:]), nil
+}
+
+//sys	pipe(p *[2]int32) (err error)
+
+func Pipe(p []int) (err error) {
+	if len(p) != 2 {
+		return syscall.ErrorString("bad arg in system call")
+	}
+	var pp [2]int32
+	err = pipe(&pp)
+	if err == nil {
+		p[0] = int(pp[0])
+		p[1] = int(pp[1])
+	}
+	return
+}
+
+// Underlying system call writes to newoffset via pointer.
+// Implemented in assembly to avoid allocation.
+func seek(placeholder uintptr, fd int, offset int64, whence int) (newoffset int64, err string)
+
+func Seek(fd int, offset int64, whence int) (newoffset int64, err error) {
+	newoffset, e := seek(0, fd, offset, whence)
+
+	if newoffset == -1 {
+		err = syscall.ErrorString(e)
+	}
+	return
+}
+
+func Mkdir(path string, mode uint32) (err error) {
+	fd, err := Create(path, O_RDONLY, DMDIR|mode)
+
+	if fd != -1 {
+		Close(fd)
+	}
+
+	return
+}
+
+type Waitmsg struct {
+	Pid  int
+	Time [3]uint32
+	Msg  string
+}
+
+func (w Waitmsg) Exited() bool   { return true }
+func (w Waitmsg) Signaled() bool { return false }
+
+func (w Waitmsg) ExitStatus() int {
+	if len(w.Msg) == 0 {
+		// a normal exit returns no message
+		return 0
+	}
+	return 1
+}
+
+//sys	await(s []byte) (n int, err error)
+
+func Await(w *Waitmsg) (err error) {
+	var buf [512]byte
+	var f [5][]byte
+
+	n, err := await(buf[:])
+
+	if err != nil || w == nil {
+		return
+	}
+
+	nf := 0
+	p := 0
+	for i := 0; i < n && nf < len(f)-1; i++ {
+		if buf[i] == ' ' {
+			f[nf] = buf[p:i]
+			p = i + 1
+			nf++
+		}
+	}
+	f[nf] = buf[p:]
+	nf++
+
+	if nf != len(f) {
+		return syscall.ErrorString("invalid wait message")
+	}
+	w.Pid = int(atoi(f[0]))
+	w.Time[0] = uint32(atoi(f[1]))
+	w.Time[1] = uint32(atoi(f[2]))
+	w.Time[2] = uint32(atoi(f[3]))
+	w.Msg = cstring(f[4])
+	if w.Msg == "''" {
+		// await() returns '' for no error
+		w.Msg = ""
+	}
+	return
+}
+
+func Unmount(name, old string) (err error) {
+	fixwd()
+	oldp, err := BytePtrFromString(old)
+	if err != nil {
+		return err
+	}
+	oldptr := uintptr(unsafe.Pointer(oldp))
+
+	var r0 uintptr
+	var e syscall.ErrorString
+
+	// bind(2) man page: If name is zero, everything bound or mounted upon old is unbound or unmounted.
+	if name == "" {
+		r0, _, e = Syscall(SYS_UNMOUNT, _zero, oldptr, 0)
+	} else {
+		namep, err := BytePtrFromString(name)
+		if err != nil {
+			return err
+		}
+		r0, _, e = Syscall(SYS_UNMOUNT, uintptr(unsafe.Pointer(namep)), oldptr, 0)
+	}
+
+	if int32(r0) == -1 {
+		err = e
+	}
+	return
+}
+
+func Fchdir(fd int) (err error) {
+	path, err := Fd2path(fd)
+
+	if err != nil {
+		return
+	}
+
+	return Chdir(path)
+}
+
+type Timespec struct {
+	Sec  int32
+	Nsec int32
+}
+
+type Timeval struct {
+	Sec  int32
+	Usec int32
+}
+
+func NsecToTimeval(nsec int64) (tv Timeval) {
+	nsec += 999 // round up to microsecond
+	tv.Usec = int32(nsec % 1e9 / 1e3)
+	tv.Sec = int32(nsec / 1e9)
+	return
+}
+
+func nsec() int64 {
+	var scratch int64
+
+	r0, _, _ := Syscall(SYS_NSEC, uintptr(unsafe.Pointer(&scratch)), 0, 0)
+	// TODO(aram): remove hack after I fix _nsec in the pc64 kernel.
+	if r0 == 0 {
+		return scratch
+	}
+	return int64(r0)
+}
+
+func Gettimeofday(tv *Timeval) error {
+	nsec := nsec()
+	*tv = NsecToTimeval(nsec)
+	return nil
+}
+
+func Getpagesize() int { return 0x1000 }
+
+func Getegid() (egid int) { return -1 }
+func Geteuid() (euid int) { return -1 }
+func Getgid() (gid int)   { return -1 }
+func Getuid() (uid int)   { return -1 }
+
+func Getgroups() (gids []int, err error) {
+	return make([]int, 0), nil
+}
+
+//sys	open(path string, mode int) (fd int, err error)
+
+func Open(path string, mode int) (fd int, err error) {
+	fixwd()
+	return open(path, mode)
+}
+
+//sys	create(path string, mode int, perm uint32) (fd int, err error)
+
+func Create(path string, mode int, perm uint32) (fd int, err error) {
+	fixwd()
+	return create(path, mode, perm)
+}
+
+//sys	remove(path string) (err error)
+
+func Remove(path string) error {
+	fixwd()
+	return remove(path)
+}
+
+//sys	stat(path string, edir []byte) (n int, err error)
+
+func Stat(path string, edir []byte) (n int, err error) {
+	fixwd()
+	return stat(path, edir)
+}
+
+//sys	bind(name string, old string, flag int) (err error)
+
+func Bind(name string, old string, flag int) (err error) {
+	fixwd()
+	return bind(name, old, flag)
+}
+
+//sys	mount(fd int, afd int, old string, flag int, aname string) (err error)
+
+func Mount(fd int, afd int, old string, flag int, aname string) (err error) {
+	fixwd()
+	return mount(fd, afd, old, flag, aname)
+}
+
+//sys	wstat(path string, edir []byte) (err error)
+
+func Wstat(path string, edir []byte) (err error) {
+	fixwd()
+	return wstat(path, edir)
+}
+
+//sys	chdir(path string) (err error)
+//sys	Dup(oldfd int, newfd int) (fd int, err error)
+//sys	Pread(fd int, p []byte, offset int64) (n int, err error)
+//sys	Pwrite(fd int, p []byte, offset int64) (n int, err error)
+//sys	Close(fd int) (err error)
+//sys	Fstat(fd int, edir []byte) (n int, err error)
+//sys	Fwstat(fd int, edir []byte) (err error)

vendor/golang.org/x/sys/plan9/zsyscall_plan9_386.go

@@ -0,0 +1,284 @@
+// go run mksyscall.go -l32 -plan9 -tags plan9,386 syscall_plan9.go
+// Code generated by the command above; see README.md. DO NOT EDIT.
+
+//go:build plan9 && 386
+
+package plan9
+
+import "unsafe"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func fd2path(fd int, buf []byte) (err error) {
+	var _p0 unsafe.Pointer
+	if len(buf) > 0 {
+		_p0 = unsafe.Pointer(&buf[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_FD2PATH, uintptr(fd), uintptr(_p0), uintptr(len(buf)))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func pipe(p *[2]int32) (err error) {
+	r0, _, e1 := Syscall(SYS_PIPE, uintptr(unsafe.Pointer(p)), 0, 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func await(s []byte) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(s) > 0 {
+		_p0 = unsafe.Pointer(&s[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_AWAIT, uintptr(_p0), uintptr(len(s)), 0)
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func open(path string, mode int) (fd int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_OPEN, uintptr(unsafe.Pointer(_p0)), uintptr(mode), 0)
+	fd = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func create(path string, mode int, perm uint32) (fd int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_CREATE, uintptr(unsafe.Pointer(_p0)), uintptr(mode), uintptr(perm))
+	fd = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func remove(path string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_REMOVE, uintptr(unsafe.Pointer(_p0)), 0, 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func stat(path string, edir []byte) (n int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	var _p1 unsafe.Pointer
+	if len(edir) > 0 {
+		_p1 = unsafe.Pointer(&edir[0])
+	} else {
+		_p1 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_STAT, uintptr(unsafe.Pointer(_p0)), uintptr(_p1), uintptr(len(edir)))
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func bind(name string, old string, flag int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(name)
+	if err != nil {
+		return
+	}
+	var _p1 *byte
+	_p1, err = BytePtrFromString(old)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_BIND, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(_p1)), uintptr(flag))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func mount(fd int, afd int, old string, flag int, aname string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(old)
+	if err != nil {
+		return
+	}
+	var _p1 *byte
+	_p1, err = BytePtrFromString(aname)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall6(SYS_MOUNT, uintptr(fd), uintptr(afd), uintptr(unsafe.Pointer(_p0)), uintptr(flag), uintptr(unsafe.Pointer(_p1)), 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func wstat(path string, edir []byte) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	var _p1 unsafe.Pointer
+	if len(edir) > 0 {
+		_p1 = unsafe.Pointer(&edir[0])
+	} else {
+		_p1 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_WSTAT, uintptr(unsafe.Pointer(_p0)), uintptr(_p1), uintptr(len(edir)))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func chdir(path string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_CHDIR, uintptr(unsafe.Pointer(_p0)), 0, 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Dup(oldfd int, newfd int) (fd int, err error) {
+	r0, _, e1 := Syscall(SYS_DUP, uintptr(oldfd), uintptr(newfd), 0)
+	fd = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Pread(fd int, p []byte, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(p) > 0 {
+		_p0 = unsafe.Pointer(&p[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall6(SYS_PREAD, uintptr(fd), uintptr(_p0), uintptr(len(p)), uintptr(offset), uintptr(offset>>32), 0)
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Pwrite(fd int, p []byte, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(p) > 0 {
+		_p0 = unsafe.Pointer(&p[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall6(SYS_PWRITE, uintptr(fd), uintptr(_p0), uintptr(len(p)), uintptr(offset), uintptr(offset>>32), 0)
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Close(fd int) (err error) {
+	r0, _, e1 := Syscall(SYS_CLOSE, uintptr(fd), 0, 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fstat(fd int, edir []byte) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(edir) > 0 {
+		_p0 = unsafe.Pointer(&edir[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_FSTAT, uintptr(fd), uintptr(_p0), uintptr(len(edir)))
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fwstat(fd int, edir []byte) (err error) {
+	var _p0 unsafe.Pointer
+	if len(edir) > 0 {
+		_p0 = unsafe.Pointer(&edir[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_FWSTAT, uintptr(fd), uintptr(_p0), uintptr(len(edir)))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}

vendor/golang.org/x/sys/plan9/zsyscall_plan9_amd64.go

@@ -0,0 +1,284 @@
+// go run mksyscall.go -l32 -plan9 -tags plan9,amd64 syscall_plan9.go
+// Code generated by the command above; see README.md. DO NOT EDIT.
+
+//go:build plan9 && amd64
+
+package plan9
+
+import "unsafe"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func fd2path(fd int, buf []byte) (err error) {
+	var _p0 unsafe.Pointer
+	if len(buf) > 0 {
+		_p0 = unsafe.Pointer(&buf[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_FD2PATH, uintptr(fd), uintptr(_p0), uintptr(len(buf)))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func pipe(p *[2]int32) (err error) {
+	r0, _, e1 := Syscall(SYS_PIPE, uintptr(unsafe.Pointer(p)), 0, 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func await(s []byte) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(s) > 0 {
+		_p0 = unsafe.Pointer(&s[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_AWAIT, uintptr(_p0), uintptr(len(s)), 0)
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func open(path string, mode int) (fd int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_OPEN, uintptr(unsafe.Pointer(_p0)), uintptr(mode), 0)
+	fd = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func create(path string, mode int, perm uint32) (fd int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_CREATE, uintptr(unsafe.Pointer(_p0)), uintptr(mode), uintptr(perm))
+	fd = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func remove(path string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_REMOVE, uintptr(unsafe.Pointer(_p0)), 0, 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func stat(path string, edir []byte) (n int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	var _p1 unsafe.Pointer
+	if len(edir) > 0 {
+		_p1 = unsafe.Pointer(&edir[0])
+	} else {
+		_p1 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_STAT, uintptr(unsafe.Pointer(_p0)), uintptr(_p1), uintptr(len(edir)))
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func bind(name string, old string, flag int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(name)
+	if err != nil {
+		return
+	}
+	var _p1 *byte
+	_p1, err = BytePtrFromString(old)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_BIND, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(_p1)), uintptr(flag))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func mount(fd int, afd int, old string, flag int, aname string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(old)
+	if err != nil {
+		return
+	}
+	var _p1 *byte
+	_p1, err = BytePtrFromString(aname)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall6(SYS_MOUNT, uintptr(fd), uintptr(afd), uintptr(unsafe.Pointer(_p0)), uintptr(flag), uintptr(unsafe.Pointer(_p1)), 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func wstat(path string, edir []byte) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	var _p1 unsafe.Pointer
+	if len(edir) > 0 {
+		_p1 = unsafe.Pointer(&edir[0])
+	} else {
+		_p1 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_WSTAT, uintptr(unsafe.Pointer(_p0)), uintptr(_p1), uintptr(len(edir)))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func chdir(path string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_CHDIR, uintptr(unsafe.Pointer(_p0)), 0, 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Dup(oldfd int, newfd int) (fd int, err error) {
+	r0, _, e1 := Syscall(SYS_DUP, uintptr(oldfd), uintptr(newfd), 0)
+	fd = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Pread(fd int, p []byte, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(p) > 0 {
+		_p0 = unsafe.Pointer(&p[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall6(SYS_PREAD, uintptr(fd), uintptr(_p0), uintptr(len(p)), uintptr(offset), uintptr(offset>>32), 0)
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Pwrite(fd int, p []byte, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(p) > 0 {
+		_p0 = unsafe.Pointer(&p[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall6(SYS_PWRITE, uintptr(fd), uintptr(_p0), uintptr(len(p)), uintptr(offset), uintptr(offset>>32), 0)
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Close(fd int) (err error) {
+	r0, _, e1 := Syscall(SYS_CLOSE, uintptr(fd), 0, 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fstat(fd int, edir []byte) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(edir) > 0 {
+		_p0 = unsafe.Pointer(&edir[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_FSTAT, uintptr(fd), uintptr(_p0), uintptr(len(edir)))
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fwstat(fd int, edir []byte) (err error) {
+	var _p0 unsafe.Pointer
+	if len(edir) > 0 {
+		_p0 = unsafe.Pointer(&edir[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_FWSTAT, uintptr(fd), uintptr(_p0), uintptr(len(edir)))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}

vendor/golang.org/x/sys/plan9/zsyscall_plan9_arm.go

@@ -0,0 +1,284 @@
+// go run mksyscall.go -l32 -plan9 -tags plan9,arm syscall_plan9.go
+// Code generated by the command above; see README.md. DO NOT EDIT.
+
+//go:build plan9 && arm
+
+package plan9
+
+import "unsafe"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func fd2path(fd int, buf []byte) (err error) {
+	var _p0 unsafe.Pointer
+	if len(buf) > 0 {
+		_p0 = unsafe.Pointer(&buf[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_FD2PATH, uintptr(fd), uintptr(_p0), uintptr(len(buf)))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func pipe(p *[2]int32) (err error) {
+	r0, _, e1 := Syscall(SYS_PIPE, uintptr(unsafe.Pointer(p)), 0, 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func await(s []byte) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(s) > 0 {
+		_p0 = unsafe.Pointer(&s[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_AWAIT, uintptr(_p0), uintptr(len(s)), 0)
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func open(path string, mode int) (fd int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_OPEN, uintptr(unsafe.Pointer(_p0)), uintptr(mode), 0)
+	fd = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func create(path string, mode int, perm uint32) (fd int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_CREATE, uintptr(unsafe.Pointer(_p0)), uintptr(mode), uintptr(perm))
+	fd = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func remove(path string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_REMOVE, uintptr(unsafe.Pointer(_p0)), 0, 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func stat(path string, edir []byte) (n int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	var _p1 unsafe.Pointer
+	if len(edir) > 0 {
+		_p1 = unsafe.Pointer(&edir[0])
+	} else {
+		_p1 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_STAT, uintptr(unsafe.Pointer(_p0)), uintptr(_p1), uintptr(len(edir)))
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func bind(name string, old string, flag int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(name)
+	if err != nil {
+		return
+	}
+	var _p1 *byte
+	_p1, err = BytePtrFromString(old)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_BIND, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(_p1)), uintptr(flag))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func mount(fd int, afd int, old string, flag int, aname string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(old)
+	if err != nil {
+		return
+	}
+	var _p1 *byte
+	_p1, err = BytePtrFromString(aname)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall6(SYS_MOUNT, uintptr(fd), uintptr(afd), uintptr(unsafe.Pointer(_p0)), uintptr(flag), uintptr(unsafe.Pointer(_p1)), 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func wstat(path string, edir []byte) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	var _p1 unsafe.Pointer
+	if len(edir) > 0 {
+		_p1 = unsafe.Pointer(&edir[0])
+	} else {
+		_p1 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_WSTAT, uintptr(unsafe.Pointer(_p0)), uintptr(_p1), uintptr(len(edir)))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func chdir(path string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_CHDIR, uintptr(unsafe.Pointer(_p0)), 0, 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Dup(oldfd int, newfd int) (fd int, err error) {
+	r0, _, e1 := Syscall(SYS_DUP, uintptr(oldfd), uintptr(newfd), 0)
+	fd = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Pread(fd int, p []byte, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(p) > 0 {
+		_p0 = unsafe.Pointer(&p[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall6(SYS_PREAD, uintptr(fd), uintptr(_p0), uintptr(len(p)), uintptr(offset), uintptr(offset>>32), 0)
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Pwrite(fd int, p []byte, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(p) > 0 {
+		_p0 = unsafe.Pointer(&p[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall6(SYS_PWRITE, uintptr(fd), uintptr(_p0), uintptr(len(p)), uintptr(offset), uintptr(offset>>32), 0)
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Close(fd int) (err error) {
+	r0, _, e1 := Syscall(SYS_CLOSE, uintptr(fd), 0, 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fstat(fd int, edir []byte) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(edir) > 0 {
+		_p0 = unsafe.Pointer(&edir[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_FSTAT, uintptr(fd), uintptr(_p0), uintptr(len(edir)))
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fwstat(fd int, edir []byte) (err error) {
+	var _p0 unsafe.Pointer
+	if len(edir) > 0 {
+		_p0 = unsafe.Pointer(&edir[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_FWSTAT, uintptr(fd), uintptr(_p0), uintptr(len(edir)))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}

vendor/golang.org/x/sys/plan9/zsysnum_plan9.go

@@ -0,0 +1,49 @@
+// mksysnum_plan9.sh /opt/plan9/sys/src/libc/9syscall/sys.h
+// MACHINE GENERATED BY THE ABOVE COMMAND; DO NOT EDIT
+
+package plan9
+
+const (
+	SYS_SYSR1       = 0
+	SYS_BIND        = 2
+	SYS_CHDIR       = 3
+	SYS_CLOSE       = 4
+	SYS_DUP         = 5
+	SYS_ALARM       = 6
+	SYS_EXEC        = 7
+	SYS_EXITS       = 8
+	SYS_FAUTH       = 10
+	SYS_SEGBRK      = 12
+	SYS_OPEN        = 14
+	SYS_OSEEK       = 16
+	SYS_SLEEP       = 17
+	SYS_RFORK       = 19
+	SYS_PIPE        = 21
+	SYS_CREATE      = 22
+	SYS_FD2PATH     = 23
+	SYS_BRK_        = 24
+	SYS_REMOVE      = 25
+	SYS_NOTIFY      = 28
+	SYS_NOTED       = 29
+	SYS_SEGATTACH   = 30
+	SYS_SEGDETACH   = 31
+	SYS_SEGFREE     = 32
+	SYS_SEGFLUSH    = 33
+	SYS_RENDEZVOUS  = 34
+	SYS_UNMOUNT     = 35
+	SYS_SEMACQUIRE  = 37
+	SYS_SEMRELEASE  = 38
+	SYS_SEEK        = 39
+	SYS_FVERSION    = 40
+	SYS_ERRSTR      = 41
+	SYS_STAT        = 42
+	SYS_FSTAT       = 43
+	SYS_WSTAT       = 44
+	SYS_FWSTAT      = 45
+	SYS_MOUNT       = 46
+	SYS_AWAIT       = 47
+	SYS_PREAD       = 50
+	SYS_PWRITE      = 51
+	SYS_TSEMACQUIRE = 52
+	SYS_NSEC        = 53
+)

vendor/golang.org/x/text/width/kind_string.go

@@ -0,0 +1,28 @@
+// Code generated by "stringer -type=Kind"; DO NOT EDIT.
+
+package width
+
+import "strconv"
+
+func _() {
+	// An "invalid array index" compiler error signifies that the constant values have changed.
+	// Re-run the stringer command to generate them again.
+	var x [1]struct{}
+	_ = x[Neutral-0]
+	_ = x[EastAsianAmbiguous-1]
+	_ = x[EastAsianWide-2]
+	_ = x[EastAsianNarrow-3]
+	_ = x[EastAsianFullwidth-4]
+	_ = x[EastAsianHalfwidth-5]
+}
+
+const _Kind_name = "NeutralEastAsianAmbiguousEastAsianWideEastAsianNarrowEastAsianFullwidthEastAsianHalfwidth"
+
+var _Kind_index = [...]uint8{0, 7, 25, 38, 53, 71, 89}
+
+func (i Kind) String() string {
+	if i < 0 || i >= Kind(len(_Kind_index)-1) {
+		return "Kind(" + strconv.FormatInt(int64(i), 10) + ")"
+	}
+	return _Kind_name[_Kind_index[i]:_Kind_index[i+1]]
+}

vendor/golang.org/x/text/width/transform.go

@@ -0,0 +1,239 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package width
+
+import (
+	"unicode/utf8"
+
+	"golang.org/x/text/transform"
+)
+
+type foldTransform struct {
+	transform.NopResetter
+}
+
+func (foldTransform) Span(src []byte, atEOF bool) (n int, err error) {
+	for n < len(src) {
+		if src[n] < utf8.RuneSelf {
+			// ASCII fast path.
+			for n++; n < len(src) && src[n] < utf8.RuneSelf; n++ {
+			}
+			continue
+		}
+		v, size := trie.lookup(src[n:])
+		if size == 0 { // incomplete UTF-8 encoding
+			if !atEOF {
+				err = transform.ErrShortSrc
+			} else {
+				n = len(src)
+			}
+			break
+		}
+		if elem(v)&tagNeedsFold != 0 {
+			err = transform.ErrEndOfSpan
+			break
+		}
+		n += size
+	}
+	return n, err
+}
+
+func (foldTransform) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
+	for nSrc < len(src) {
+		if src[nSrc] < utf8.RuneSelf {
+			// ASCII fast path.
+			start, end := nSrc, len(src)
+			if d := len(dst) - nDst; d < end-start {
+				end = nSrc + d
+			}
+			for nSrc++; nSrc < end && src[nSrc] < utf8.RuneSelf; nSrc++ {
+			}
+			n := copy(dst[nDst:], src[start:nSrc])
+			if nDst += n; nDst == len(dst) {
+				nSrc = start + n
+				if nSrc == len(src) {
+					return nDst, nSrc, nil
+				}
+				if src[nSrc] < utf8.RuneSelf {
+					return nDst, nSrc, transform.ErrShortDst
+				}
+			}
+			continue
+		}
+		v, size := trie.lookup(src[nSrc:])
+		if size == 0 { // incomplete UTF-8 encoding
+			if !atEOF {
+				return nDst, nSrc, transform.ErrShortSrc
+			}
+			size = 1 // gobble 1 byte
+		}
+		if elem(v)&tagNeedsFold == 0 {
+			if size != copy(dst[nDst:], src[nSrc:nSrc+size]) {
+				return nDst, nSrc, transform.ErrShortDst
+			}
+			nDst += size
+		} else {
+			data := inverseData[byte(v)]
+			if len(dst)-nDst < int(data[0]) {
+				return nDst, nSrc, transform.ErrShortDst
+			}
+			i := 1
+			for end := int(data[0]); i < end; i++ {
+				dst[nDst] = data[i]
+				nDst++
+			}
+			dst[nDst] = data[i] ^ src[nSrc+size-1]
+			nDst++
+		}
+		nSrc += size
+	}
+	return nDst, nSrc, nil
+}
+
+type narrowTransform struct {
+	transform.NopResetter
+}
+
+func (narrowTransform) Span(src []byte, atEOF bool) (n int, err error) {
+	for n < len(src) {
+		if src[n] < utf8.RuneSelf {
+			// ASCII fast path.
+			for n++; n < len(src) && src[n] < utf8.RuneSelf; n++ {
+			}
+			continue
+		}
+		v, size := trie.lookup(src[n:])
+		if size == 0 { // incomplete UTF-8 encoding
+			if !atEOF {
+				err = transform.ErrShortSrc
+			} else {
+				n = len(src)
+			}
+			break
+		}
+		if k := elem(v).kind(); byte(v) == 0 || k != EastAsianFullwidth && k != EastAsianWide && k != EastAsianAmbiguous {
+		} else {
+			err = transform.ErrEndOfSpan
+			break
+		}
+		n += size
+	}
+	return n, err
+}
+
+func (narrowTransform) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
+	for nSrc < len(src) {
+		if src[nSrc] < utf8.RuneSelf {
+			// ASCII fast path.
+			start, end := nSrc, len(src)
+			if d := len(dst) - nDst; d < end-start {
+				end = nSrc + d
+			}
+			for nSrc++; nSrc < end && src[nSrc] < utf8.RuneSelf; nSrc++ {
+			}
+			n := copy(dst[nDst:], src[start:nSrc])
+			if nDst += n; nDst == len(dst) {
+				nSrc = start + n
+				if nSrc == len(src) {
+					return nDst, nSrc, nil
+				}
+				if src[nSrc] < utf8.RuneSelf {
+					return nDst, nSrc, transform.ErrShortDst
+				}
+			}
+			continue
+		}
+		v, size := trie.lookup(src[nSrc:])
+		if size == 0 { // incomplete UTF-8 encoding
+			if !atEOF {
+				return nDst, nSrc, transform.ErrShortSrc
+			}
+			size = 1 // gobble 1 byte
+		}
+		if k := elem(v).kind(); byte(v) == 0 || k != EastAsianFullwidth && k != EastAsianWide && k != EastAsianAmbiguous {
+			if size != copy(dst[nDst:], src[nSrc:nSrc+size]) {
+				return nDst, nSrc, transform.ErrShortDst
+			}
+			nDst += size
+		} else {
+			data := inverseData[byte(v)]
+			if len(dst)-nDst < int(data[0]) {
+				return nDst, nSrc, transform.ErrShortDst
+			}
+			i := 1
+			for end := int(data[0]); i < end; i++ {
+				dst[nDst] = data[i]
+				nDst++
+			}
+			dst[nDst] = data[i] ^ src[nSrc+size-1]
+			nDst++
+		}
+		nSrc += size
+	}
+	return nDst, nSrc, nil
+}
+
+type wideTransform struct {
+	transform.NopResetter
+}
+
+func (wideTransform) Span(src []byte, atEOF bool) (n int, err error) {
+	for n < len(src) {
+		// TODO: Consider ASCII fast path. Special-casing ASCII handling can
+		// reduce the ns/op of BenchmarkWideASCII by about 30%. This is probably
+		// not enough to warrant the extra code and complexity.
+		v, size := trie.lookup(src[n:])
+		if size == 0 { // incomplete UTF-8 encoding
+			if !atEOF {
+				err = transform.ErrShortSrc
+			} else {
+				n = len(src)
+			}
+			break
+		}
+		if k := elem(v).kind(); byte(v) == 0 || k != EastAsianHalfwidth && k != EastAsianNarrow {
+		} else {
+			err = transform.ErrEndOfSpan
+			break
+		}
+		n += size
+	}
+	return n, err
+}
+
+func (wideTransform) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
+	for nSrc < len(src) {
+		// TODO: Consider ASCII fast path. Special-casing ASCII handling can
+		// reduce the ns/op of BenchmarkWideASCII by about 30%. This is probably
+		// not enough to warrant the extra code and complexity.
+		v, size := trie.lookup(src[nSrc:])
+		if size == 0 { // incomplete UTF-8 encoding
+			if !atEOF {
+				return nDst, nSrc, transform.ErrShortSrc
+			}
+			size = 1 // gobble 1 byte
+		}
+		if k := elem(v).kind(); byte(v) == 0 || k != EastAsianHalfwidth && k != EastAsianNarrow {
+			if size != copy(dst[nDst:], src[nSrc:nSrc+size]) {
+				return nDst, nSrc, transform.ErrShortDst
+			}
+			nDst += size
+		} else {
+			data := inverseData[byte(v)]
+			if len(dst)-nDst < int(data[0]) {
+				return nDst, nSrc, transform.ErrShortDst
+			}
+			i := 1
+			for end := int(data[0]); i < end; i++ {
+				dst[nDst] = data[i]
+				nDst++
+			}
+			dst[nDst] = data[i] ^ src[nSrc+size-1]
+			nDst++
+		}
+		nSrc += size
+	}
+	return nDst, nSrc, nil
+}

vendor/golang.org/x/text/width/trieval.go

@@ -0,0 +1,30 @@
+// Code generated by running "go generate" in golang.org/x/text. DO NOT EDIT.
+
+package width
+
+// elem is an entry of the width trie. The high byte is used to encode the type
+// of the rune. The low byte is used to store the index to a mapping entry in
+// the inverseData array.
+type elem uint16
+
+const (
+	tagNeutral elem = iota << typeShift
+	tagAmbiguous
+	tagWide
+	tagNarrow
+	tagFullwidth
+	tagHalfwidth
+)
+
+const (
+	numTypeBits = 3
+	typeShift   = 16 - numTypeBits
+
+	// tagNeedsFold is true for all fullwidth and halfwidth runes except for
+	// the Won sign U+20A9.
+	tagNeedsFold = 0x1000
+
+	// The Korean Won sign is halfwidth, but SHOULD NOT be mapped to a wide
+	// variant.
+	wonSign rune = 0x20A9
+)

vendor/golang.org/x/text/width/width.go

@@ -0,0 +1,206 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:generate stringer -type=Kind
+//go:generate go run gen.go gen_common.go gen_trieval.go
+
+// Package width provides functionality for handling different widths in text.
+//
+// Wide characters behave like ideographs; they tend to allow line breaks after
+// each character and remain upright in vertical text layout. Narrow characters
+// are kept together in words or runs that are rotated sideways in vertical text
+// layout.
+//
+// For more information, see https://unicode.org/reports/tr11/.
+package width // import "golang.org/x/text/width"
+
+import (
+	"unicode/utf8"
+
+	"golang.org/x/text/transform"
+)
+
+// TODO
+// 1) Reduce table size by compressing blocks.
+// 2) API proposition for computing display length
+//    (approximation, fixed pitch only).
+// 3) Implement display length.
+
+// Kind indicates the type of width property as defined in https://unicode.org/reports/tr11/.
+type Kind int
+
+const (
+	// Neutral characters do not occur in legacy East Asian character sets.
+	Neutral Kind = iota
+
+	// EastAsianAmbiguous characters that can be sometimes wide and sometimes
+	// narrow and require additional information not contained in the character
+	// code to further resolve their width.
+	EastAsianAmbiguous
+
+	// EastAsianWide characters are wide in its usual form. They occur only in
+	// the context of East Asian typography. These runes may have explicit
+	// halfwidth counterparts.
+	EastAsianWide
+
+	// EastAsianNarrow characters are narrow in its usual form. They often have
+	// fullwidth counterparts.
+	EastAsianNarrow
+
+	// Note: there exist Narrow runes that do not have fullwidth or wide
+	// counterparts, despite what the definition says (e.g. U+27E6).
+
+	// EastAsianFullwidth characters have a compatibility decompositions of type
+	// wide that map to a narrow counterpart.
+	EastAsianFullwidth
+
+	// EastAsianHalfwidth characters have a compatibility decomposition of type
+	// narrow that map to a wide or ambiguous counterpart, plus U+20A9 ₩ WON
+	// SIGN.
+	EastAsianHalfwidth
+
+	// Note: there exist runes that have a halfwidth counterparts but that are
+	// classified as Ambiguous, rather than wide (e.g. U+2190).
+)
+
+// TODO: the generated tries need to return size 1 for invalid runes for the
+// width to be computed correctly (each byte should render width 1)
+
+var trie = newWidthTrie(0)
+
+// Lookup reports the Properties of the first rune in b and the number of bytes
+// of its UTF-8 encoding.
+func Lookup(b []byte) (p Properties, size int) {
+	v, sz := trie.lookup(b)
+	return Properties{elem(v), b[sz-1]}, sz
+}
+
+// LookupString reports the Properties of the first rune in s and the number of
+// bytes of its UTF-8 encoding.
+func LookupString(s string) (p Properties, size int) {
+	v, sz := trie.lookupString(s)
+	return Properties{elem(v), s[sz-1]}, sz
+}
+
+// LookupRune reports the Properties of rune r.
+func LookupRune(r rune) Properties {
+	var buf [4]byte
+	n := utf8.EncodeRune(buf[:], r)
+	v, _ := trie.lookup(buf[:n])
+	last := byte(r)
+	if r >= utf8.RuneSelf {
+		last = 0x80 + byte(r&0x3f)
+	}
+	return Properties{elem(v), last}
+}
+
+// Properties provides access to width properties of a rune.
+type Properties struct {
+	elem elem
+	last byte
+}
+
+func (e elem) kind() Kind {
+	return Kind(e >> typeShift)
+}
+
+// Kind returns the Kind of a rune as defined in Unicode TR #11.
+// See https://unicode.org/reports/tr11/ for more details.
+func (p Properties) Kind() Kind {
+	return p.elem.kind()
+}
+
+// Folded returns the folded variant of a rune or 0 if the rune is canonical.
+func (p Properties) Folded() rune {
+	if p.elem&tagNeedsFold != 0 {
+		buf := inverseData[byte(p.elem)]
+		buf[buf[0]] ^= p.last
+		r, _ := utf8.DecodeRune(buf[1 : 1+buf[0]])
+		return r
+	}
+	return 0
+}
+
+// Narrow returns the narrow variant of a rune or 0 if the rune is already
+// narrow or doesn't have a narrow variant.
+func (p Properties) Narrow() rune {
+	if k := p.elem.kind(); byte(p.elem) != 0 && (k == EastAsianFullwidth || k == EastAsianWide || k == EastAsianAmbiguous) {
+		buf := inverseData[byte(p.elem)]
+		buf[buf[0]] ^= p.last
+		r, _ := utf8.DecodeRune(buf[1 : 1+buf[0]])
+		return r
+	}
+	return 0
+}
+
+// Wide returns the wide variant of a rune or 0 if the rune is already
+// wide or doesn't have a wide variant.
+func (p Properties) Wide() rune {
+	if k := p.elem.kind(); byte(p.elem) != 0 && (k == EastAsianHalfwidth || k == EastAsianNarrow) {
+		buf := inverseData[byte(p.elem)]
+		buf[buf[0]] ^= p.last
+		r, _ := utf8.DecodeRune(buf[1 : 1+buf[0]])
+		return r
+	}
+	return 0
+}
+
+// TODO for Properties:
+// - Add Fullwidth/Halfwidth or Inverted methods for computing variants
+// mapping.
+// - Add width information (including information on non-spacing runes).
+
+// Transformer implements the transform.Transformer interface.
+type Transformer struct {
+	t transform.SpanningTransformer
+}
+
+// Reset implements the transform.Transformer interface.
+func (t Transformer) Reset() { t.t.Reset() }
+
+// Transform implements the transform.Transformer interface.
+func (t Transformer) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error) {
+	return t.t.Transform(dst, src, atEOF)
+}
+
+// Span implements the transform.SpanningTransformer interface.
+func (t Transformer) Span(src []byte, atEOF bool) (n int, err error) {
+	return t.t.Span(src, atEOF)
+}
+
+// Bytes returns a new byte slice with the result of applying t to b.
+func (t Transformer) Bytes(b []byte) []byte {
+	b, _, _ = transform.Bytes(t, b)
+	return b
+}
+
+// String returns a string with the result of applying t to s.
+func (t Transformer) String(s string) string {
+	s, _, _ = transform.String(t, s)
+	return s
+}
+
+var (
+	// Fold is a transform that maps all runes to their canonical width.
+	//
+	// Note that the NFKC and NFKD transforms in golang.org/x/text/unicode/norm
+	// provide a more generic folding mechanism.
+	Fold Transformer = Transformer{foldTransform{}}
+
+	// Widen is a transform that maps runes to their wide variant, if
+	// available.
+	Widen Transformer = Transformer{wideTransform{}}
+
+	// Narrow is a transform that maps runes to their narrow variant, if
+	// available.
+	Narrow Transformer = Transformer{narrowTransform{}}
+)
+
+// TODO: Consider the following options:
+// - Treat Ambiguous runes that have a halfwidth counterpart as wide, or some
+//   generalized variant of this.
+// - Consider a wide Won character to be the default width (or some generalized
+//   variant of this).
+// - Filter the set of characters that gets converted (the preferred approach is
+//   to allow applying filters to transforms).

vendor/modules.txt

@@ -329,6 +329,14 @@ github.com/davecgh/go-spew/spew
 # github.com/dennwc/varint v1.0.0
 ## explicit; go 1.12
 github.com/dennwc/varint
+# github.com/ergochat/readline v0.1.3
+## explicit; go 1.19
+github.com/ergochat/readline
+github.com/ergochat/readline/internal/ansi
+github.com/ergochat/readline/internal/platform
+github.com/ergochat/readline/internal/ringbuf
+github.com/ergochat/readline/internal/runes
+github.com/ergochat/readline/internal/term
 # github.com/fatih/color v1.17.0
 ## explicit; go 1.17
 github.com/fatih/color
@@ -714,6 +722,7 @@ golang.org/x/sync/semaphore
 # golang.org/x/sys v0.25.0
 ## explicit; go 1.18
 golang.org/x/sys/cpu
+golang.org/x/sys/plan9
 golang.org/x/sys/unix
 golang.org/x/sys/windows
 golang.org/x/sys/windows/registry
@@ -723,6 +732,7 @@ golang.org/x/text/secure/bidirule
 golang.org/x/text/transform
 golang.org/x/text/unicode/bidi
 golang.org/x/text/unicode/norm
+golang.org/x/text/width
 # golang.org/x/time v0.6.0
 ## explicit; go 1.18
 golang.org/x/time/rate