feat(archive): add rar archive support

archive/archive.go

@@ -64,7 +64,9 @@ func NewArchive(path string, pageCache *pagecache.PageCache, httpReferer string)
 	switch ext {
 	case "zip", "cbz":
 		return NewZip(path)
-	case "7z", "rar", "tar", "tgz", "gz", "tbz2", "cb7", "cbr", "cbt", "lha":
+	case "rar":
+		return NewRar(path)
+	case "7z", "tar", "tgz", "gz", "tbz2", "cb7", "cbr", "cbt", "lha":
 		return nil, errors.New("Archive type not supported, please unpack it first")
 	}
 

archive/rar.go

@@ -0,0 +1,162 @@
+/*
+ * Copyright (c) 2013-2021 Utkan Güngördü <utkan@freeconsole.org>
+ * Copyright (c) 2021-2023 Piotr Grabowski
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package archive
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"log"
+	"path/filepath"
+	"sort"
+
+	"github.com/fauu/gomicsv/pixbuf"
+	"github.com/gotk3/gotk3/gdk"
+	"github.com/nwaples/rardecode/v2"
+)
+
+type Rar struct {
+	files  RarMembers // Sorted by name
+	reader *rardecode.ReadCloser
+	name   string
+}
+
+type RarMember struct {
+	Header *rardecode.FileHeader
+	Offset int // in terms of files
+}
+
+type RarMembers []RarMember
+
+func (p RarMembers) Len() int           { return len(p) }
+func (p RarMembers) Less(i, j int) bool { return strcmp(p[i].Header.Name, p[j].Header.Name, true) }
+func (p RarMembers) Swap(i, j int)      { p[i], p[j] = p[j], p[i] }
+
+// NewRar reads supported image filenames from a given rar archive and sorts them
+func NewRar(name string) (*Rar, error) {
+	var err error
+
+	ar := new(Rar)
+
+	ar.name = filepath.Base(name)
+	ar.files = make([]RarMember, 0, MaxArchiveEntries)
+	ar.reader, err = rardecode.OpenReader(name)
+	if err != nil {
+		return nil, err
+	}
+
+	offsetAcc := -1
+	for {
+		offsetAcc += 1
+
+		header, err := ar.reader.Next()
+		if err != nil {
+			if err == io.EOF {
+				break
+			}
+			log.Printf("error reading a file inside the rar archive: %v", err)
+		}
+		if header.IsDir {
+			continue
+		}
+		if !extensionMatches(header.Name, imageExtensions) {
+			continue
+		}
+		ar.files = append(ar.files, RarMember{
+			Header: header,
+			Offset: offsetAcc,
+		})
+	}
+
+	if len(ar.files) == 0 {
+		return nil, errors.New(ar.name + ": no supported images in the rar file")
+	}
+
+	sort.Sort(RarMembers(ar.files))
+
+	ar.Close()
+
+	return ar, nil
+}
+
+func (ar *Rar) checkbounds(i int) error {
+	if i < 0 || i >= len(ar.files) {
+		return ErrBounds
+	}
+	return nil
+}
+
+func (ar *Rar) Load(i int, autorotate bool, _nPreload int) (*gdk.Pixbuf, error) {
+	var err error
+	if err = ar.checkbounds(i); err != nil {
+		return nil, err
+	}
+
+	ar.reader, err = rardecode.OpenReader(ar.name)
+	if err != nil {
+		return nil, err
+	}
+
+	targetOffset := ar.files[i].Offset
+	offsetAcc := -1
+	for {
+		offsetAcc += 1
+
+		header, err := ar.reader.Next()
+		if err != nil {
+			if err == io.EOF {
+				break
+			}
+			log.Printf("error reading a file inside the rar archive: %v", err)
+		}
+		if header.IsDir {
+			continue
+		}
+		if offsetAcc == targetOffset {
+			defer ar.Close()
+			return pixbuf.Load(ar.reader, autorotate)
+		}
+	}
+
+	return nil, fmt.Errorf(ar.name + ": could not find a file inside the rar archive")
+}
+
+func (ar *Rar) Kind() Kind {
+	return Packed
+}
+
+func (ar *Rar) ArchiveName() string {
+	return ar.name
+}
+
+func (ar *Rar) Name(i int) (string, error) {
+	if err := ar.checkbounds(i); err != nil {
+		return "", err
+	}
+	return ar.files[i].Header.Name, nil
+}
+
+func (ar *Rar) Len() *int {
+	l := len(ar.files)
+	return &l
+}
+
+func (ar *Rar) Close() error {
+	return ar.reader.Close()
+}

archive/util.go

@@ -37,7 +37,7 @@ type Loader interface {
 	Len() int
 }
 
-var archiveExtensions = []string{".zip", ".cbz"}
+var archiveExtensions = []string{".zip", ".cbz", ".rar"}
 var imageExtensions []string
 
 func init() {

go.mod

@@ -7,6 +7,7 @@ go 1.20
 require (
 	github.com/flytam/filenamify v1.2.0
 	github.com/gotk3/gotk3 v0.6.2
+	github.com/nwaples/rardecode/v2 v2.0.0-beta.2
 	github.com/spf13/pflag v1.0.5
 	golang.org/x/sys v0.14.0
 )

go.sum

@@ -6,6 +6,8 @@ github.com/gotk3/gotk3 v0.6.1 h1:GJ400a0ecEEWrzjBvzBzH+pB/esEMIGdB9zPSmBdoeo=
 github.com/gotk3/gotk3 v0.6.1/go.mod h1:/hqFpkNa9T3JgNAE2fLvCdov7c5bw//FHNZrZ3Uv9/Q=
 github.com/gotk3/gotk3 v0.6.2 h1:sx/PjaKfKULJPTPq8p2kn2ZbcNFxpOJqi4VLzMbEOO8=
 github.com/gotk3/gotk3 v0.6.2/go.mod h1:/hqFpkNa9T3JgNAE2fLvCdov7c5bw//FHNZrZ3Uv9/Q=
+github.com/nwaples/rardecode/v2 v2.0.0-beta.2 h1:e3mzJFJs4k83GXBEiTaQ5HgSc/kOK8q0rDaRO0MPaOk=
+github.com/nwaples/rardecode/v2 v2.0.0-beta.2/go.mod h1:yntwv/HfMc/Hbvtq9I19D1n58te3h6KsqCf3GxyfBGY=
 github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
 github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
 golang.org/x/sys v0.4.0 h1:Zr2JFtRQNX3BCZ8YtxRE9hNJYC8J6I1MVbMg6owUp18=

gomicsv.ui

@@ -23,6 +23,7 @@
     <mime-types>
       <mime-type>application/zip</mime-type>
       <mime-type>application/x-cbz</mime-type>
+      <mime-type>application/vnd.rar</mime-type>
     </mime-types>
   </object>
   <object class="GtkRecentFilter" id="RecentFilter">