Add zip2zip tool to copy zip entries from one file to another
This doesn't do any decompression / recompression, but just copies over
the already compressed contents. So it's similar to zip -U, but allows
rewriting of the paths.
The first expected usecase is to replace img_from_target_files during
the build, since it does the equivalent of this:
zip2zip -i <target-files.zip> -o <img.zip> OTA/android-info.txt:android-info.txt IMAGES/*:.
Except it decompresses and recompresses the images, which takes over a
minute instead of a few seconds.
Change-Id: I88d0df188635088783223873f78e193272dbdf1c
diff --git a/third_party/zip/android.go b/third_party/zip/android.go
new file mode 100644
index 0000000..7a3a221
--- /dev/null
+++ b/third_party/zip/android.go
@@ -0,0 +1,70 @@
+// Copyright 2016 Google Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package zip
+
+import (
+ "io"
+)
+
+func (w *Writer) CopyFrom(orig *File, newName string) error {
+ if w.last != nil && !w.last.closed {
+ if err := w.last.close(); err != nil {
+ return err
+ }
+ w.last = nil
+ }
+
+ fileHeader := orig.FileHeader
+ fileHeader.Name = newName
+ fh := &fileHeader
+ fh.Flags |= 0x8
+
+ h := &header{
+ FileHeader: fh,
+ offset: uint64(w.cw.count),
+ }
+ w.dir = append(w.dir, h)
+
+ if err := writeHeader(w.cw, fh); err != nil {
+ return err
+ }
+
+ // Copy data
+ dataOffset, err := orig.DataOffset()
+ if err != nil {
+ return err
+ }
+ io.Copy(w.cw, io.NewSectionReader(orig.zipr, dataOffset, int64(orig.CompressedSize64)))
+
+ // Write data descriptor.
+ var buf []byte
+ if fh.isZip64() {
+ buf = make([]byte, dataDescriptor64Len)
+ } else {
+ buf = make([]byte, dataDescriptorLen)
+ }
+ b := writeBuf(buf)
+ b.uint32(dataDescriptorSignature)
+ b.uint32(fh.CRC32)
+ if fh.isZip64() {
+ b.uint64(fh.CompressedSize64)
+ b.uint64(fh.UncompressedSize64)
+ } else {
+ b.uint32(fh.CompressedSize)
+ b.uint32(fh.UncompressedSize)
+ }
+ _, err = w.cw.Write(buf)
+ return err
+}