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

1 files changed, 128 insertions, 0 deletions

diff --git a/cmd/zip2zip/zip2zip.go b/cmd/zip2zip/zip2zip.go
new file mode 100644
index 00000000..8e7523ff
--- /dev/null
+++ b/cmd/zip2zip/zip2zip.go
@@ -0,0 +1,128 @@
+// 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 main
+
+import (
+	"flag"
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"android/soong/third_party/zip"
+)
+
+var (
+	input  = flag.String("i", "", "zip file to read from")
+	output = flag.String("o", "", "output file")
+)
+
+func usage() {
+	fmt.Fprintln(os.Stderr, "usage: zip2zip -i zipfile -o zipfile [filespec]...")
+	flag.PrintDefaults()
+	fmt.Fprintln(os.Stderr, "  filespec:")
+	fmt.Fprintln(os.Stderr, "    <name>")
+	fmt.Fprintln(os.Stderr, "    <in_name>:<out_name>")
+	fmt.Fprintln(os.Stderr, "    <glob>:<out_dir>/")
+	fmt.Fprintln(os.Stderr, "")
+	fmt.Fprintln(os.Stderr, "Files will be copied with their existing compression from the input zipfile to")
+	fmt.Fprintln(os.Stderr, "the output zipfile, in the order of filespec arguments")
+	os.Exit(2)
+}
+
+func main() {
+	flag.Parse()
+
+	if flag.NArg() == 0 || *input == "" || *output == "" {
+		usage()
+	}
+
+	reader, err := zip.OpenReader(*input)
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(3)
+	}
+	defer reader.Close()
+
+	output, err := os.Create(*output)
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(4)
+	}
+	defer output.Close()
+
+	writer := zip.NewWriter(output)
+	defer func() {
+		err := writer.Close()
+		if err != nil {
+			fmt.Fprintln(os.Stderr, err)
+			os.Exit(5)
+		}
+	}()
+
+	for _, arg := range flag.Args() {
+		var input string
+		var output string
+
+		// Reserve escaping for future implementation, so make sure no
+		// one is using \ and expecting a certain behavior.
+		if strings.Contains(arg, "\\") {
+			fmt.Fprintln(os.Stderr, "\\ characters are not currently supported")
+			os.Exit(6)
+		}
+
+		args := strings.SplitN(arg, ":", 2)
+		input = args[0]
+		if len(args) == 2 {
+			output = args[1]
+		}
+
+		if strings.IndexAny(input, "*?[") >= 0 {
+			for _, file := range reader.File {
+				if match, err := filepath.Match(input, file.Name); err != nil {
+					fmt.Fprintln(os.Stderr, err)
+					os.Exit(7)
+				} else if match {
+					var newFileName string
+					if output == "" {
+						newFileName = file.Name
+					} else {
+						_, name := filepath.Split(file.Name)
+						newFileName = filepath.Join(output, name)
+					}
+					err = writer.CopyFrom(file, newFileName)
+					if err != nil {
+						fmt.Fprintln(os.Stderr, err)
+						os.Exit(8)
+					}
+				}
+			}
+		} else {
+			if output == "" {
+				output = input
+			}
+			for _, file := range reader.File {
+				if input == file.Name {
+					err = writer.CopyFrom(file, output)
+					if err != nil {
+						fmt.Fprintln(os.Stderr, err)
+						os.Exit(8)
+					}
+					break
+				}
+			}
+		}
+	}
+}