Merge pull request #481 from smira/data-tar-gz-as-tar

Add workaround for reading data.tar.gz as data.tar

Gomfile

@@ -5,6 +5,7 @@ gom 'github.com/cheggaaa/pb', :commit => '2c1b74620cc58a81ac152ee2d322e28c806d81
 gom 'github.com/DisposaBoy/JsonConfigReader', :commit => '33a99fdf1d5ee1f79b5077e9c06f955ad356d5f4'
 gom 'github.com/gin-gonic/gin', :commit => 'b1758d3bfa09e61ddbc1c9a627e936eec6a170de'
 gom 'github.com/go-ini/ini', :commit => 'afbd495e5aaea13597b5e14fe514ddeaa4d76fc3'
+gom 'github.com/h2non/filetype/matchers', :commit => '259d9d2c52bc90dbd7e1999f9da86ee0d104d0ff'
 gom 'github.com/jlaffaye/ftp', :commit => 'fec71e62e457557fbe85cefc847a048d57815d76'
 gom 'github.com/jmespath/go-jmespath', :commit => '0b12d6b521d83fc7f755e7cfc1b1fbdd35a01a74'
 gom 'github.com/julienschmidt/httprouter', :commit => '46807412fe50aaceb73bb57061c2230fd26a1640'

deb/deb.go

@@ -2,16 +2,20 @@ package deb
 
 import (
 	"archive/tar"
+	"bufio"
 	"compress/bzip2"
 	"compress/gzip"
 	"fmt"
-	"github.com/mkrautz/goar"
-	"github.com/smira/aptly/utils"
-	"github.com/smira/go-xz"
-	"github.com/smira/lzma"
 	"io"
 	"os"
 	"strings"
+
+	"github.com/h2non/filetype/matchers"
+	"github.com/mkrautz/goar"
+
+	"github.com/smira/aptly/utils"
+	"github.com/smira/go-xz"
+	"github.com/smira/lzma"
 )
 
 // GetControlFileFromDeb reads control file from deb package
@@ -119,29 +123,41 @@ func GetContentsFromDeb(packageFile string) ([]string, error) {
 		}
 
 		if strings.HasPrefix(header.Name, "data.tar") {
+			bufReader := bufio.NewReader(library)
+			signature, err := bufReader.Peek(270)
+
+			var isTar bool
+			if err == nil {
+				isTar = matchers.Tar(signature)
+			}
+
 			var tarInput io.Reader
 
 			switch header.Name {
 			case "data.tar":
-				tarInput = library
+				tarInput = bufReader
 			case "data.tar.gz":
-				ungzip, err := gzip.NewReader(library)
+				if isTar {
+					tarInput = bufReader
+				} else {
+					ungzip, err := gzip.NewReader(bufReader)
 					if err != nil {
 						return nil, fmt.Errorf("unable to ungzip data.tar.gz from %s: %s", packageFile, err)
 					}
 					defer ungzip.Close()
 					tarInput = ungzip
+				}
 			case "data.tar.bz2":
-				tarInput = bzip2.NewReader(library)
+				tarInput = bzip2.NewReader(bufReader)
 			case "data.tar.xz":
-				unxz, err := xz.NewReader(library)
+				unxz, err := xz.NewReader(bufReader)
 				if err != nil {
 					return nil, fmt.Errorf("unable to unxz data.tar.xz from %s: %s", packageFile, err)
 				}
 				defer unxz.Close()
 				tarInput = unxz
 			case "data.tar.lzma":
-				unlzma := lzma.NewReader(library)
+				unlzma := lzma.NewReader(bufReader)
 				defer unlzma.Close()
 				tarInput = unlzma
 			default: