all: initial stubs for Windows support; see https://github.com/VictoriaMetrics/VictoriaMetrics/issues/70

lib/filestream/filestream_windows.go

@@ -0,0 +1,9 @@
+package filestream
+
+func (st *streamTracker) adviseDontNeed(n int, fdatasync bool) error {
+	return nil
+}
+
+func (st *streamTracker) close() error {
+	return nil
+}

lib/memory/memory_windows.go

@@ -0,0 +1,40 @@
+package memory
+
+import (
+	"syscall"
+	"unsafe"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
+)
+
+// This has been adapted from https://github.com/pbnjay/memory.
+
+type memStatusEx struct {
+	dwLength     uint32
+	dwMemoryLoad uint32
+	ullTotalPhys uint64
+	unused       [6]uint64
+}
+
+func sysTotalMemory() int {
+	kernel32, err := syscall.LoadDLL("kernel32.dll")
+	if err != nil {
+		logger.Panicf("FATAL: cannot load kernel32.dll: %s", err)
+	}
+	globalMemoryStatusEx, err := kernel32.FindProc("GlobalMemoryStatusEx")
+	if err != nil {
+		logger.Panicf("FATAL: cannot find GlobalMemoryStatusEx: %s", err)
+	}
+	msx := &memStatusEx{
+		dwLength: uint32(unsafe.Sizeof(memStatusEx{})),
+	}
+	r, _, err := globalMemoryStatusEx.Call(uintptr(unsafe.Pointer(msx)))
+	if r == 0 {
+		logger.Panicf("FATAL: error in GlobalMemoryStatusEx: %s", err)
+	}
+	n := int(msx.ullTotalPhys)
+	if uint64(n) != msx.ullTotalPhys {
+		logger.Panicf("FATAL: int overflow for msx.ullTotalPhys=%d", msx.ullTotalPhys)
+	}
+	return n
+}