tar是用于文件归档，gzip用于压缩。仅仅用tar的话，达不到压缩的目的。我们常见的tar.gz就是用gzip压缩生成的tar归档文件。
go实现tar压缩与解压与zip类似，区别在于tar需要使用gzip进行处理。tar与zip的Header不同。代码如下
package tartest
import (
"archive/tar"
"compress/gzip"
"io"
"os"
"strings"
)
//压缩 使用gzip压缩成tar.gz
func Compress(files []*os.File, dest string) error {
d, _ := os.Create(dest)
defer d.Close()
gw := gzip.NewWriter(d)
defer gw.Close()
tw := tar.NewWriter(gw)
defer tw.Close()
for _, file := range files {
err := compress(file, "", tw)
if err != nil {
return err
}
}
return nil
}
func compress(file *os.File, prefix string, tw *tar.Writer) error {
info, err := file.Stat()
if err != nil {
return err
}
if info.IsDir() {
prefix = prefix + "/" + info.Name()
fileInfos, err := file.Readdir(-1)
if err != nil {
return err
}
for _, fi := range fileInfos {
f, err := os.Open(file.Name() + "/" + fi.Name())
if err != nil {
return err
}
err = compress(f, prefix, tw)
if err != nil {
return err
}
}
} else {
header, err := tar.FileInfoHeader(info, "")
header.Name = prefix + "/" + header.Name
if err != nil {
return err
}
err = tw.WriteHeader(header)
if err != nil {
return err
}
_, err = io.Copy(tw, file)
file.Close()
if err != nil {
return err
}
}
return nil
}
//解压 tar.gz
func DeCompress(tarFile, dest string) error {
srcFile, err := os.Open(tarFile)
if err != nil {
return err
}
defer srcFile.Close()
gr, err := gzip.NewReader(srcFile)
if err != nil {
return err
}
defer gr.Close()
tr := tar.NewReader(gr)
for {
hdr, err := tr.Next()
if err != nil {
if err == io.EOF {
break
} else {
return err
}
}
filename := dest + hdr.Name
file, err := createFile(filename)
if err != nil {
return err
}
io.Copy(file, tr)
}
return nil
}
func createFile(name string) (*os.File, error) {
err := os.MkdirAll(string([]rune(name)[0:strings.LastIndex(name, "/")]), 0755)
if err != nil {
return nil, err
}
return os.Create(name)
}
