syncthing/cmd/stwatchfile/main.go

99 lines
1.8 KiB
Go

// Copyright (C) 2015 The Syncthing Authors.
//
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this file,
// You can obtain one at https://mozilla.org/MPL/2.0/.
package main
import (
"flag"
"fmt"
"io"
"os"
"time"
_ "github.com/syncthing/syncthing/lib/automaxprocs"
"github.com/syncthing/syncthing/lib/sha256"
)
func main() {
period := flag.Duration("period", 200*time.Millisecond, "Sleep period between checks")
flag.Parse()
file := flag.Arg(0)
if file == "" {
fmt.Println("Expects a path as an argument")
return
}
exists := true
size := int64(0)
mtime := time.Time{}
var hash [sha256.Size]byte
for {
time.Sleep(*period)
newExists := true
fi, err := os.Stat(file)
if err != nil && os.IsNotExist(err) {
newExists = false
} else if err != nil {
fmt.Println("stat:", err)
return
}
if newExists != exists {
exists = newExists
if !newExists {
fmt.Println(file, "does not exist")
} else {
fmt.Println(file, "appeared")
}
}
if !exists {
size = 0
mtime = time.Time{}
hash = [sha256.Size]byte{}
continue
}
if fi.IsDir() {
fmt.Println(file, "is directory")
return
}
newSize := fi.Size()
newMtime := fi.ModTime()
newHash, err := sha256file(file)
if err != nil {
fmt.Println("sha256file:", err)
}
if newSize != size || newMtime != mtime || newHash != hash {
fmt.Println(file, "Size:", newSize, "Mtime:", newMtime, "Hash:", fmt.Sprintf("%x", newHash))
hash = newHash
size = newSize
mtime = newMtime
}
}
}
func sha256file(fname string) (hash [sha256.Size]byte, err error) {
f, err := os.Open(fname)
if err != nil {
return
}
defer f.Close()
h := sha256.New()
io.Copy(h, f)
hb := h.Sum(nil)
copy(hash[:], hb)
return
}