Replace extract-srcjars.sh with zipsync tool

extract_srcjars.sh uses zipinfo and unzip, which fail with an
error on an empty zip file.  Instead of trying to hack around
this (which is hard to make guarantees for since they are
non-hermetic host tools), replace them with a go tool to unzip
a set of zip files into a directory.

Bug: 73885582
Test: m checkbuild
Change-Id: I151fed347ed5196726e36866ffc27bc831799afb
Merged-In: I151fed347ed5196726e36866ffc27bc831799afb
(cherry picked from commit 436b76564d83586c68025985bc5d9fc7774109bf)
diff --git a/cmd/zipsync/Android.bp b/cmd/zipsync/Android.bp
new file mode 100644
index 0000000..22feadc
--- /dev/null
+++ b/cmd/zipsync/Android.bp
@@ -0,0 +1,25 @@
+// 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.
+
+blueprint_go_binary {
+    name: "zipsync",
+    deps: [
+        "android-archive-zip",
+        "blueprint-pathtools",
+    ],
+    srcs: [
+        "zipsync.go",
+    ],
+}
+
diff --git a/cmd/zipsync/zipsync.go b/cmd/zipsync/zipsync.go
new file mode 100644
index 0000000..035a145
--- /dev/null
+++ b/cmd/zipsync/zipsync.go
@@ -0,0 +1,124 @@
+// Copyright 2018 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 (
+	"archive/zip"
+	"flag"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"log"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+var (
+	outputDir  = flag.String("d", "", "output dir")
+	outputFile = flag.String("l", "", "output list file")
+	filter     = flag.String("f", "", "optional filter pattern")
+)
+
+func must(err error) {
+	if err != nil {
+		log.Fatal(err)
+	}
+}
+
+func writeFile(filename string, in io.Reader, perm os.FileMode) error {
+	out, err := os.OpenFile(filename, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, perm)
+	if err != nil {
+		return err
+	}
+	_, err = io.Copy(out, in)
+	if err != nil {
+		out.Close()
+		return err
+	}
+
+	return out.Close()
+}
+
+func main() {
+	flag.Usage = func() {
+		fmt.Fprintln(os.Stderr, "usage: zipsync -d <output dir> [-l <output file>] [-f <pattern>] [zip]...")
+		flag.PrintDefaults()
+	}
+
+	flag.Parse()
+
+	if *outputDir == "" {
+		flag.Usage()
+		os.Exit(1)
+	}
+
+	inputs := flag.Args()
+
+	// For now, just wipe the output directory and replace its contents with the zip files
+	// Eventually this could only modify the directory contents as necessary to bring it up
+	// to date with the zip files.
+	must(os.RemoveAll(*outputDir))
+
+	must(os.MkdirAll(*outputDir, 0777))
+
+	var files []string
+	seen := make(map[string]string)
+
+	for _, input := range inputs {
+		reader, err := zip.OpenReader(input)
+		if err != nil {
+			log.Fatal(err)
+		}
+		defer reader.Close()
+
+		for _, f := range reader.File {
+			if *filter != "" {
+				if match, err := filepath.Match(*filter, filepath.Base(f.Name)); err != nil {
+					log.Fatal(err)
+				} else if !match {
+					continue
+				}
+			}
+			if filepath.IsAbs(f.Name) {
+				log.Fatal("%q in %q is an absolute path", f.Name, input)
+			}
+
+			if prev, exists := seen[f.Name]; exists {
+				log.Fatal("%q found in both %q and %q", f.Name, prev, input)
+			}
+			seen[f.Name] = input
+
+			filename := filepath.Join(*outputDir, f.Name)
+			if f.FileInfo().IsDir() {
+				must(os.MkdirAll(filename, f.FileInfo().Mode()))
+			} else {
+				must(os.MkdirAll(filepath.Dir(filename), 0777))
+				in, err := f.Open()
+				if err != nil {
+					log.Fatal(err)
+				}
+				must(writeFile(filename, in, f.FileInfo().Mode()))
+				in.Close()
+				files = append(files, filename)
+			}
+		}
+	}
+
+	if *outputFile != "" {
+		data := strings.Join(files, "\n") + "\n"
+		must(ioutil.WriteFile(*outputFile, []byte(data), 0666))
+	}
+}
diff --git a/java/builder.go b/java/builder.go
index 6d894a3..bc95599 100644
--- a/java/builder.go
+++ b/java/builder.go
@@ -41,7 +41,7 @@
 	javac = pctx.AndroidGomaStaticRule("javac",
 		blueprint.RuleParams{
 			Command: `rm -rf "$outDir" "$annoDir" "$srcJarDir" && mkdir -p "$outDir" "$annoDir" "$srcJarDir" && ` +
-				`${config.ExtractSrcJarsCmd} $srcJarDir $srcJarDir/list $srcJars && ` +
+				`${config.ZipSyncCmd} -d $srcJarDir -l $srcJarDir/list -f "*.java" $srcJars && ` +
 				`${config.SoongJavacWrapper} ${config.JavacWrapper}${config.JavacCmd} ${config.JavacHeapFlags} ${config.CommonJdkFlags} ` +
 				`$javacFlags $bootClasspath $classpath ` +
 				`-source $javaVersion -target $javaVersion ` +
@@ -50,7 +50,7 @@
 			CommandDeps: []string{
 				"${config.JavacCmd}",
 				"${config.SoongZipCmd}",
-				"${config.ExtractSrcJarsCmd}",
+				"${config.ZipSyncCmd}",
 			},
 			CommandOrderOnly: []string{"${config.SoongJavacWrapper}"},
 			Rspfile:          "$out.rsp",
@@ -62,7 +62,7 @@
 	kotlinc = pctx.AndroidGomaStaticRule("kotlinc",
 		blueprint.RuleParams{
 			Command: `rm -rf "$outDir" "$srcJarDir" && mkdir -p "$outDir" "$srcJarDir" && ` +
-				`${config.ExtractSrcJarsCmd} $srcJarDir $srcJarDir/list $srcJars && ` +
+				`${config.ZipSyncCmd} -d $srcJarDir -l $srcJarDir/list -f "*.java" $srcJars && ` +
 				`${config.GenKotlinBuildFileCmd} $classpath $outDir $out.rsp $srcJarDir/list > $outDir/kotlinc-build.xml &&` +
 				`${config.KotlincCmd} $kotlincFlags ` +
 				`-jvm-target $kotlinJvmTarget -Xbuild-file=$outDir/kotlinc-build.xml && ` +
@@ -72,7 +72,7 @@
 				"${config.KotlinCompilerJar}",
 				"${config.GenKotlinBuildFileCmd}",
 				"${config.SoongZipCmd}",
-				"${config.ExtractSrcJarsCmd}",
+				"${config.ZipSyncCmd}",
 			},
 			Rspfile:        "$out.rsp",
 			RspfileContent: `$in`,
@@ -82,7 +82,7 @@
 	errorprone = pctx.AndroidStaticRule("errorprone",
 		blueprint.RuleParams{
 			Command: `rm -rf "$outDir" "$annoDir" "$srcJarDir" && mkdir -p "$outDir" "$annoDir" "$srcJarDir" && ` +
-				`${config.ExtractSrcJarsCmd} $srcJarDir $srcJarDir/list $srcJars && ` +
+				`${config.ZipSyncCmd} -d $srcJarDir -l $srcJarDir/list -f "*.java" $srcJars && ` +
 				`${config.SoongJavacWrapper} ${config.ErrorProneCmd} ` +
 				`$javacFlags $bootClasspath $classpath ` +
 				`-source $javaVersion -target $javaVersion ` +
@@ -93,7 +93,7 @@
 				"${config.ErrorProneJavacJar}",
 				"${config.ErrorProneJar}",
 				"${config.SoongZipCmd}",
-				"${config.ExtractSrcJarsCmd}",
+				"${config.ZipSyncCmd}",
 			},
 			CommandOrderOnly: []string{"${config.SoongJavacWrapper}"},
 			Rspfile:          "$out.rsp",
diff --git a/java/config/config.go b/java/config/config.go
index e985e69..37f6528 100644
--- a/java/config/config.go
+++ b/java/config/config.go
@@ -84,13 +84,13 @@
 	pctx.SourcePathVariable("JrtFsJar", "${JavaHome}/lib/jrt-fs.jar")
 	pctx.SourcePathVariable("Ziptime", "prebuilts/build-tools/${hostPrebuiltTag}/bin/ziptime")
 
-	pctx.SourcePathVariable("ExtractSrcJarsCmd", "build/soong/scripts/extract-srcjars.sh")
 	pctx.SourcePathVariable("GenKotlinBuildFileCmd", "build/soong/scripts/gen-kotlin-build-file.sh")
 
 	pctx.SourcePathVariable("JarArgsCmd", "build/soong/scripts/jar-args.sh")
 	pctx.HostBinToolVariable("SoongZipCmd", "soong_zip")
 	pctx.HostBinToolVariable("MergeZipsCmd", "merge_zips")
 	pctx.HostBinToolVariable("Zip2ZipCmd", "zip2zip")
+	pctx.HostBinToolVariable("ZipSyncCmd", "zipsync")
 	pctx.VariableFunc("DxCmd", func(config android.Config) (string, error) {
 		if config.IsEnvFalse("USE_D8") {
 			if config.UnbundledBuild() || config.IsPdkBuild() {
diff --git a/java/config/makevars.go b/java/config/makevars.go
index 7e125d5..5210f20 100644
--- a/java/config/makevars.go
+++ b/java/config/makevars.go
@@ -73,7 +73,7 @@
 	}
 
 	ctx.Strict("SOONG_JAVAC_WRAPPER", "${SoongJavacWrapper}")
-	ctx.Strict("EXTRACT_SRCJARS", "${ExtractSrcJarsCmd}")
+	ctx.Strict("ZIPSYNC", "${ZipSyncCmd}")
 
 	ctx.Strict("JACOCO_CLI_JAR", "${JacocoCLIJar}")
 	ctx.Strict("DEFAULT_JACOCO_EXCLUDE_FILTER", strings.Join(DefaultJacocoExcludeFilter, ","))
diff --git a/java/droiddoc.go b/java/droiddoc.go
index 9d6f58e..7171c91 100644
--- a/java/droiddoc.go
+++ b/java/droiddoc.go
@@ -27,14 +27,14 @@
 	javadoc = pctx.AndroidStaticRule("javadoc",
 		blueprint.RuleParams{
 			Command: `rm -rf "$outDir" "$srcJarDir" "$stubsDir" && mkdir -p "$outDir" "$srcJarDir" "$stubsDir" && ` +
-				`${config.ExtractSrcJarsCmd} $srcJarDir $srcJarDir/list $srcJars && ` +
+				`${config.ZipSyncCmd} -d $srcJarDir -l $srcJarDir/list -f "*.java" $srcJars && ` +
 				`${config.JavadocCmd} -encoding UTF-8 @$out.rsp @$srcJarDir/list ` +
 				`$opts $bootclasspathArgs $classpathArgs -sourcepath $sourcepath ` +
 				`-d $outDir -quiet  && ` +
 				`${config.SoongZipCmd} -write_if_changed -d -o $docZip -C $outDir -D $outDir && ` +
 				`${config.SoongZipCmd} -write_if_changed -jar -o $out -C $stubsDir -D $stubsDir`,
 			CommandDeps: []string{
-				"${config.ExtractSrcJarsCmd}",
+				"${config.ZipSyncCmd}",
 				"${config.JavadocCmd}",
 				"${config.SoongZipCmd}",
 				"$JsilverJar",
diff --git a/scripts/extract-srcjars.sh b/scripts/extract-srcjars.sh
deleted file mode 100755
index f81032b..0000000
--- a/scripts/extract-srcjars.sh
+++ /dev/null
@@ -1,44 +0,0 @@
-#!/bin/bash -e
-
-# Copyright 2017 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.
-
-# Extracts .java files from source jars in a specified directory and writes out a list of the files
-
-if [ -z "$1" -o -z "$2" ]; then
-  echo "usage: $0 <output dir> <output file> [<jar> ...]" >&2
-  exit 1
-fi
-
-output_dir=$1
-shift
-output_file=$1
-shift
-
-rm -f $output_file
-touch $output_file
-
-for j in "$@"; do
-  for f in $(zipinfo -1 $j '*.java'); do
-    echo $output_dir/$f >> $output_file
-  done
-  unzip -qn -d $output_dir $j '*.java'
-done
-
-duplicates=$(cat $output_file | sort | uniq -d | uniq)
-if [ -n "$duplicates" ]; then
-  echo Duplicate source files:
-  echo $duplicates
-  exit 1
-fi