more tools

tools/md5.go

@@ -0,0 +1,121 @@
+// Copyright 2013 <chaishushan{AT}gmail.com>. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build ingore
+
+//
+// Cacl dir or file MD5Sum, support regexp.
+//
+// Example:
+//	md5 file
+//	md5 dir "\.go$"
+//	md5 dir "\.tiff?$"
+//	md5 dir "\.tiff?|jpg|jpeg$"
+//
+// Help:
+//	cpdir -h
+//
+package main
+
+import (
+	"crypto/md5"
+	"fmt"
+	"io/ioutil"
+	"log"
+	"os"
+	"path/filepath"
+	"regexp"
+	"sort"
+)
+
+const usage = `
+Usage: md5 [dir|file [filter]]
+       md5 -h
+
+Example:
+  md5 file
+  md5 dir "\.go$"
+  md5 dir "\.go$"
+  md5 dir "\.tiff?$"
+  md5 dir "\.tiff?|jpg|jpeg$"
+    
+Report bugs to <chaishushan{AT}gmail.com>.
+`
+
+func main() {
+	if len(os.Args) < 2 {
+		fmt.Fprintln(os.Stderr, usage[1:len(usage)-1])
+		os.Exit(0)
+	}
+	filter := ".*"
+	if len(os.Args) > 2 {
+		filter = os.Args[2]
+	}
+
+	if name := os.Args[1]; IsDir(name) {
+		m, err := MD5Dir(name, filter)
+		if err != nil {
+			log.Fatalf("%s: %v", name, err)
+		}
+		var paths []string
+		for path := range m {
+			paths = append(paths, path)
+		}
+		sort.Strings(paths)
+		for _, path := range paths {
+			fmt.Printf("%x *%s\n", m[path], path)
+		}
+	} else {
+		sum, err := MD5File(name)
+		if err != nil {
+			log.Fatalf("%s: %v", name, err)
+		}
+		fmt.Printf("%x *%s\n", sum, name)
+	}
+}
+
+func IsDir(name string) bool {
+	fi, err := os.Lstat(name)
+	if err != nil {
+		log.Fatal(err)
+	}
+	return fi.IsDir()
+}
+
+func MD5Dir(root string, filter string) (map[string][md5.Size]byte, error) {
+	m := make(map[string][md5.Size]byte)
+	err := filepath.Walk(root, func(path string, info os.FileInfo, err error) error {
+		if err != nil {
+			return err
+		}
+		if info.IsDir() {
+			return nil
+		}
+		mathed, err := regexp.MatchString(filter, path)
+		if err != nil {
+			log.Fatal("regexp.MatchString: ", err)
+		}
+		if mathed {
+			data, err := ioutil.ReadFile(path)
+			if err != nil {
+				return err
+			}
+			m[path] = md5.Sum(data)
+		}
+		return nil
+	})
+	if err != nil {
+		return nil, err
+	}
+	return m, nil
+}
+
+func MD5File(filename string) (sum [md5.Size]byte, err error) {
+	data, err := ioutil.ReadFile(filename)
+	if err != nil {
+		return
+	}
+	sum = md5.Sum(data)
+	return
+}