implement xz support

selfupdate/detect.go

@@ -25,7 +25,7 @@ func findSuitableReleaseAndAsset(rels []*github.RepositoryRelease) (*github.Repo
 	// Generate candidates
 	cs := make([]string, 0, 8)
 	for _, sep := range []rune{'_', '-'} {
-		for _, ext := range []string{".zip", ".tar.gz", ".gzip", ".gz", ""} {
+		for _, ext := range []string{".zip", ".tar.gz", ".gzip", ".gz", ".tar.xz", ".xz", ""} {
 			suffix := fmt.Sprintf("%s%c%s%s", runtime.GOOS, sep, runtime.GOARCH, ext)
 			cs = append(cs, suffix)
 			if runtime.GOOS == "windows" {

selfupdate/uncompress.go

@@ -6,12 +6,32 @@ import (
 	"bytes"
 	"compress/gzip"
 	"fmt"
+	"github.com/ulikunitz/xz"
 	"io"
 	"io/ioutil"
 	"path/filepath"
 	"strings"
 )
 
+func unarchiveTar(src io.Reader, url, cmd string) (io.Reader, error) {
+	t := tar.NewReader(src)
+	for {
+		h, err := t.Next()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return nil, fmt.Errorf("Failed to unarchive .tar file: %s", err)
+		}
+		_, name := filepath.Split(h.Name)
+		if name == cmd {
+			return t, nil
+		}
+	}
+
+	return nil, fmt.Errorf("File '%s' for the command is not found in %s", cmd, url)
+}
+
 // UncompressCommand uncompresses the given source. Archive and compression format is automatically detected from 'url' parameter, which represents the URL of asset. This returns a reader for the uncompressed command given by 'cmd'.
 func UncompressCommand(src io.Reader, url, cmd string) (io.Reader, error) {
 	if strings.HasSuffix(url, ".zip") {
@@ -46,22 +66,7 @@ func UncompressCommand(src io.Reader, url, cmd string) (io.Reader, error) {
 			return nil, fmt.Errorf("Failed to uncompress .tar.gz file: %s", err)
 		}
 
-		t := tar.NewReader(gz)
-		for {
-			h, err := t.Next()
-			if err == io.EOF {
-				break
-			}
-			if err != nil {
-				return nil, fmt.Errorf("Failed to unarchive .tar file: %s", err)
-			}
-			_, name := filepath.Split(h.Name)
-			if name == cmd {
-				return t, nil
-			}
-		}
-
-		return nil, fmt.Errorf("File '%s' for the command is not found in %s", cmd, url)
+		return unarchiveTar(gz, url, cmd)
 	} else if strings.HasSuffix(url, ".gzip") || strings.HasSuffix(url, ".gz") {
 		log.Println("Uncompressing gzip file", url)
 
@@ -76,6 +81,23 @@ func UncompressCommand(src io.Reader, url, cmd string) (io.Reader, error) {
 		}
 
 		return r, nil
+	} else if strings.HasSuffix(url, ".tar.xz") {
+		log.Println("Uncompressing tar.xz file", url)
+
+		xzip, err := xz.NewReader(src)
+		if err != nil {
+			return nil, fmt.Errorf("Failed to uncompress .tar.xz file: %s", err)
+		}
+
+		return unarchiveTar(xzip, url, cmd)
+	} else if strings.HasSuffix(url, ".xz") {
+		log.Println("Uncompressing xzip file", url)
+
+		xzip, err := xz.NewReader(src)
+		if err != nil {
+			return nil, fmt.Errorf("Failed to uncompress xzip file downloaded from %s: %s", url, err)
+		}
+		return xzip, nil
 	}
 
 	log.Println("Uncompression is not needed", url)