VictoriaMetrics/vendor/github.com/prometheus/procfs/ttar
Aliaksandr Valialkin 7f4fb34182 app/vmctl: move vmctl code from github.com/VictoriaMetrics/vmctl
It is better developing vmctl tool in VictoriaMetrics repository, so it could be released
together with the rest of vmutils tools such as vmalert, vmagent, vmbackup, vmrestore and vmauth.
2021-02-01 01:18:39 +02:00

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#!/usr/bin/env bash
# Purpose: plain text tar format
# Limitations: - only suitable for text files, directories, and symlinks
# - stores only filename, content, and mode
# - not designed for untrusted input
#
# Note: must work with bash version 3.2 (macOS)
# Copyright 2017 Roger Luethi
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
set -o errexit -o nounset
# Sanitize environment (for instance, standard sorting of glob matches)
export LC_ALL=C
path=""
CMD=""
ARG_STRING="$*"
#------------------------------------------------------------------------------
# Not all sed implementations can work on null bytes. In order to make ttar
# work out of the box on macOS, use Python as a stream editor.
USE_PYTHON=0
PYTHON_CREATE_FILTER=$(cat << 'PCF'
#!/usr/bin/env python
import re
import sys
for line in sys.stdin:
line = re.sub(r'EOF', r'\EOF', line)
line = re.sub(r'NULLBYTE', r'\NULLBYTE', line)
line = re.sub('\x00', r'NULLBYTE', line)
sys.stdout.write(line)
PCF
)
PYTHON_EXTRACT_FILTER=$(cat << 'PEF'
#!/usr/bin/env python
import re
import sys
for line in sys.stdin:
line = re.sub(r'(?<!\\)NULLBYTE', '\x00', line)
line = re.sub(r'\\NULLBYTE', 'NULLBYTE', line)
line = re.sub(r'([^\\])EOF', r'\1', line)
line = re.sub(r'\\EOF', 'EOF', line)
sys.stdout.write(line)
PEF
)
function test_environment {
if [[ "$(echo "a" | sed 's/a/\x0/' | wc -c)" -ne 2 ]]; then
echo "WARNING sed unable to handle null bytes, using Python (slow)."
if ! which python >/dev/null; then
echo "ERROR Python not found. Aborting."
exit 2
fi
USE_PYTHON=1
fi
}
#------------------------------------------------------------------------------
function usage {
bname=$(basename "$0")
cat << USAGE
Usage: $bname [-C <DIR>] -c -f <ARCHIVE> <FILE...> (create archive)
$bname -t -f <ARCHIVE> (list archive contents)
$bname [-C <DIR>] -x -f <ARCHIVE> (extract archive)
Options:
-C <DIR> (change directory)
-v (verbose)
--recursive-unlink (recursively delete existing directory if path
collides with file or directory to extract)
Example: Change to sysfs directory, create ttar file from fixtures directory
$bname -C sysfs -c -f sysfs/fixtures.ttar fixtures/
USAGE
exit "$1"
}
function vecho {
if [ "${VERBOSE:-}" == "yes" ]; then
echo >&7 "$@"
fi
}
function set_cmd {
if [ -n "$CMD" ]; then
echo "ERROR: more than one command given"
echo
usage 2
fi
CMD=$1
}
unset VERBOSE
unset RECURSIVE_UNLINK
while getopts :cf:-:htxvC: opt; do
case $opt in
c)
set_cmd "create"
;;
f)
ARCHIVE=$OPTARG
;;
h)
usage 0
;;
t)
set_cmd "list"
;;
x)
set_cmd "extract"
;;
v)
VERBOSE=yes
exec 7>&1
;;
C)
CDIR=$OPTARG
;;
-)
case $OPTARG in
recursive-unlink)
RECURSIVE_UNLINK="yes"
;;
*)
echo -e "Error: invalid option -$OPTARG"
echo
usage 1
;;
esac
;;
*)
echo >&2 "ERROR: invalid option -$OPTARG"
echo
usage 1
;;
esac
done
# Remove processed options from arguments
shift $(( OPTIND - 1 ));
if [ "${CMD:-}" == "" ]; then
echo >&2 "ERROR: no command given"
echo
usage 1
elif [ "${ARCHIVE:-}" == "" ]; then
echo >&2 "ERROR: no archive name given"
echo
usage 1
fi
function list {
local path=""
local size=0
local line_no=0
local ttar_file=$1
if [ -n "${2:-}" ]; then
echo >&2 "ERROR: too many arguments."
echo
usage 1
fi
if [ ! -e "$ttar_file" ]; then
echo >&2 "ERROR: file not found ($ttar_file)"
echo
usage 1
fi
while read -r line; do
line_no=$(( line_no + 1 ))
if [ $size -gt 0 ]; then
size=$(( size - 1 ))
continue
fi
if [[ $line =~ ^Path:\ (.*)$ ]]; then
path=${BASH_REMATCH[1]}
elif [[ $line =~ ^Lines:\ (.*)$ ]]; then
size=${BASH_REMATCH[1]}
echo "$path"
elif [[ $line =~ ^Directory:\ (.*)$ ]]; then
path=${BASH_REMATCH[1]}
echo "$path/"
elif [[ $line =~ ^SymlinkTo:\ (.*)$ ]]; then
echo "$path -> ${BASH_REMATCH[1]}"
fi
done < "$ttar_file"
}
function extract {
local path=""
local size=0
local line_no=0
local ttar_file=$1
if [ -n "${2:-}" ]; then
echo >&2 "ERROR: too many arguments."
echo
usage 1
fi
if [ ! -e "$ttar_file" ]; then
echo >&2 "ERROR: file not found ($ttar_file)"
echo
usage 1
fi
while IFS= read -r line; do
line_no=$(( line_no + 1 ))
local eof_without_newline
if [ "$size" -gt 0 ]; then
if [[ "$line" =~ [^\\]EOF ]]; then
# An EOF not preceded by a backslash indicates that the line
# does not end with a newline
eof_without_newline=1
else
eof_without_newline=0
fi
# Replace NULLBYTE with null byte if at beginning of line
# Replace NULLBYTE with null byte unless preceded by backslash
# Remove one backslash in front of NULLBYTE (if any)
# Remove EOF unless preceded by backslash
# Remove one backslash in front of EOF
if [ $USE_PYTHON -eq 1 ]; then
echo -n "$line" | python -c "$PYTHON_EXTRACT_FILTER" >> "$path"
else
# The repeated pattern makes up for sed's lack of negative
# lookbehind assertions (for consecutive null bytes).
echo -n "$line" | \
sed -e 's/^NULLBYTE/\x0/g;
s/\([^\\]\)NULLBYTE/\1\x0/g;
s/\([^\\]\)NULLBYTE/\1\x0/g;
s/\\NULLBYTE/NULLBYTE/g;
s/\([^\\]\)EOF/\1/g;
s/\\EOF/EOF/g;
' >> "$path"
fi
if [[ "$eof_without_newline" -eq 0 ]]; then
echo >> "$path"
fi
size=$(( size - 1 ))
continue
fi
if [[ $line =~ ^Path:\ (.*)$ ]]; then
path=${BASH_REMATCH[1]}
if [ -L "$path" ]; then
rm "$path"
elif [ -d "$path" ]; then
if [ "${RECURSIVE_UNLINK:-}" == "yes" ]; then
rm -r "$path"
else
# Safe because symlinks to directories are dealt with above
rmdir "$path"
fi
elif [ -e "$path" ]; then
rm "$path"
fi
elif [[ $line =~ ^Lines:\ (.*)$ ]]; then
size=${BASH_REMATCH[1]}
# Create file even if it is zero-length.
touch "$path"
vecho " $path"
elif [[ $line =~ ^Mode:\ (.*)$ ]]; then
mode=${BASH_REMATCH[1]}
chmod "$mode" "$path"
vecho "$mode"
elif [[ $line =~ ^Directory:\ (.*)$ ]]; then
path=${BASH_REMATCH[1]}
mkdir -p "$path"
vecho " $path/"
elif [[ $line =~ ^SymlinkTo:\ (.*)$ ]]; then
ln -s "${BASH_REMATCH[1]}" "$path"
vecho " $path -> ${BASH_REMATCH[1]}"
elif [[ $line =~ ^# ]]; then
# Ignore comments between files
continue
else
echo >&2 "ERROR: Unknown keyword on line $line_no: $line"
exit 1
fi
done < "$ttar_file"
}
function div {
echo "# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -" \
"- - - - - -"
}
function get_mode {
local mfile=$1
if [ -z "${STAT_OPTION:-}" ]; then
if stat -c '%a' "$mfile" >/dev/null 2>&1; then
# GNU stat
STAT_OPTION='-c'
STAT_FORMAT='%a'
else
# BSD stat
STAT_OPTION='-f'
# Octal output, user/group/other (omit file type, sticky bit)
STAT_FORMAT='%OLp'
fi
fi
stat "${STAT_OPTION}" "${STAT_FORMAT}" "$mfile"
}
function _create {
shopt -s nullglob
local mode
local eof_without_newline
while (( "$#" )); do
file=$1
if [ -L "$file" ]; then
echo "Path: $file"
symlinkTo=$(readlink "$file")
echo "SymlinkTo: $symlinkTo"
vecho " $file -> $symlinkTo"
div
elif [ -d "$file" ]; then
# Strip trailing slash (if there is one)
file=${file%/}
echo "Directory: $file"
mode=$(get_mode "$file")
echo "Mode: $mode"
vecho "$mode $file/"
div
# Find all files and dirs, including hidden/dot files
for x in "$file/"{*,.[^.]*}; do
_create "$x"
done
elif [ -f "$file" ]; then
echo "Path: $file"
lines=$(wc -l "$file"|awk '{print $1}')
eof_without_newline=0
if [[ "$(wc -c "$file"|awk '{print $1}')" -gt 0 ]] && \
[[ "$(tail -c 1 "$file" | wc -l)" -eq 0 ]]; then
eof_without_newline=1
lines=$((lines+1))
fi
echo "Lines: $lines"
# Add backslash in front of EOF
# Add backslash in front of NULLBYTE
# Replace null byte with NULLBYTE
if [ $USE_PYTHON -eq 1 ]; then
< "$file" python -c "$PYTHON_CREATE_FILTER"
else
< "$file" \
sed 's/EOF/\\EOF/g;
s/NULLBYTE/\\NULLBYTE/g;
s/\x0/NULLBYTE/g;
'
fi
if [[ "$eof_without_newline" -eq 1 ]]; then
# Finish line with EOF to indicate that the original line did
# not end with a linefeed
echo "EOF"
fi
mode=$(get_mode "$file")
echo "Mode: $mode"
vecho "$mode $file"
div
else
echo >&2 "ERROR: file not found ($file in $(pwd))"
exit 2
fi
shift
done
}
function create {
ttar_file=$1
shift
if [ -z "${1:-}" ]; then
echo >&2 "ERROR: missing arguments."
echo
usage 1
fi
if [ -e "$ttar_file" ]; then
rm "$ttar_file"
fi
exec > "$ttar_file"
echo "# Archive created by ttar $ARG_STRING"
_create "$@"
}
test_environment
if [ -n "${CDIR:-}" ]; then
if [[ "$ARCHIVE" != /* ]]; then
# Relative path: preserve the archive's location before changing
# directory
ARCHIVE="$(pwd)/$ARCHIVE"
fi
cd "$CDIR"
fi
"$CMD" "$ARCHIVE" "$@"