java/aapt2.go - SHIFTPHONES/android_build_soong - Gitiles

 // 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.

 package java

 import (
 	"path/filepath"
 	"sort"
 	"strconv"
 	"strings"

 	"github.com/google/blueprint"

 	"android/soong/android"
 )

 func isPathValueResource(res android.Path) bool {
 	subDir := filepath.Dir(res.String())
 	subDir, lastDir := filepath.Split(subDir)
 	return strings.HasPrefix(lastDir, "values")
 }

 // Convert input resource file path to output file path.
 // values-[config]/<file>.xml -> values-[config]_<file>.arsc.flat;
 // For other resource file, just replace the last "/" with "_" and add .flat extension.
 func pathToAapt2Path(ctx android.ModuleContext, res android.Path) android.WritablePath {

 	name := res.Base()
 	if isPathValueResource(res) {
 		name = strings.TrimSuffix(name, ".xml") + ".arsc"
 	}
 	subDir := filepath.Dir(res.String())
 	subDir, lastDir := filepath.Split(subDir)
 	name = lastDir + "_" + name + ".flat"
 	return android.PathForModuleOut(ctx, "aapt2", subDir, name)
 }

 // pathsToAapt2Paths Calls pathToAapt2Path on each entry of the given Paths, i.e. []Path.
 func pathsToAapt2Paths(ctx android.ModuleContext, resPaths android.Paths) android.WritablePaths {
 	outPaths := make(android.WritablePaths, len(resPaths))

 	for i, res := range resPaths {
 		outPaths[i] = pathToAapt2Path(ctx, res)
 	}

 	return outPaths
 }

 // Shard resource files for efficiency. See aapt2Compile for details.
 const AAPT2_SHARD_SIZE = 100

 var aapt2CompileRule = pctx.AndroidStaticRule("aapt2Compile",
 	blueprint.RuleParams{
 		Command:     `${config.Aapt2Cmd} compile -o $outDir $cFlags $in`,
 		CommandDeps: []string{"${config.Aapt2Cmd}"},
 	},
 	"outDir", "cFlags")

 // aapt2Compile compiles resources and puts the results in the requested directory.
 func aapt2Compile(ctx android.ModuleContext, dir android.Path, paths android.Paths,
 	flags []string, productToFilter string) android.WritablePaths {
 	if productToFilter != "" && productToFilter != "default" {
 		// --filter-product leaves only product-specific resources. Product-specific resources only exist
 		// in value resources (values/*.xml), so filter value resource files only. Ignore other types of
 		// resources as they don't need to be in product characteristics RRO (and they will cause aapt2
 		// compile errors)
 		filteredPaths := android.Paths{}
 		for _, path := range paths {
 			if isPathValueResource(path) {
 				filteredPaths = append(filteredPaths, path)
 			}
 		}
 		paths = filteredPaths
 		flags = append([]string{"--filter-product " + productToFilter}, flags...)
 	}

 	// Shard the input paths so that they can be processed in parallel. If we shard them into too
 	// small chunks, the additional cost of spinning up aapt2 outweighs the performance gain. The
 	// current shard size, 100, seems to be a good balance between the added cost and the gain.
 	// The aapt2 compile actions are trivially short, but each action in ninja takes on the order of
 	// ~10 ms to run. frameworks/base/core/res/res has >10k resource files, so compiling each one
 	// with an individual action could take 100 CPU seconds. Sharding them reduces the overhead of
 	// starting actions by a factor of 100, at the expense of recompiling more files when one
 	// changes.  Since the individual compiles are trivial it's a good tradeoff.
 	shards := android.ShardPaths(paths, AAPT2_SHARD_SIZE)

 	ret := make(android.WritablePaths, 0, len(paths))

 	for i, shard := range shards {
 		// This should be kept in sync with pathToAapt2Path. The aapt2 compile command takes an
 		// output directory path, but not output file paths. So, outPaths is just where we expect
 		// the output files will be located.
 		outPaths := pathsToAapt2Paths(ctx, shard)
 		ret = append(ret, outPaths...)

 		shardDesc := ""
 		if i != 0 {
 			shardDesc = " " + strconv.Itoa(i+1)
 		}

 		ctx.Build(pctx, android.BuildParams{
 			Rule:        aapt2CompileRule,
 			Description: "aapt2 compile " + dir.String() + shardDesc,
 			Inputs:      shard,
 			Outputs:     outPaths,
 			Args: map[string]string{
 				// The aapt2 compile command takes an output directory path, but not output file paths.
 				// outPaths specified above is only used for dependency management purposes. In order for
 				// the outPaths values to match the actual outputs from aapt2, the dir parameter value
 				// must be a common prefix path of the paths values, and the top-level path segment used
 				// below, "aapt2", must always be kept in sync with the one in pathToAapt2Path.
 				// TODO(b/174505750): Make this easier and robust to use.
 				"outDir": android.PathForModuleOut(ctx, "aapt2", dir.String()).String(),
 				"cFlags": strings.Join(flags, " "),
 			},
 		})
 	}

 	sort.Slice(ret, func(i, j int) bool {
 		return ret[i].String() < ret[j].String()
 	})
 	return ret
 }

 var aapt2CompileZipRule = pctx.AndroidStaticRule("aapt2CompileZip",
 	blueprint.RuleParams{
 		Command: `${config.ZipSyncCmd} -d $resZipDir $zipSyncFlags $in && ` +
 			`${config.Aapt2Cmd} compile -o $out $cFlags --dir $resZipDir`,
 		CommandDeps: []string{
 			"${config.Aapt2Cmd}",
 			"${config.ZipSyncCmd}",
 		},
 	}, "cFlags", "resZipDir", "zipSyncFlags")

 // Unzips the given compressed file and compiles the resource source files in it. The zipPrefix
 // parameter points to the subdirectory in the zip file where the resource files are located.
 func aapt2CompileZip(ctx android.ModuleContext, flata android.WritablePath, zip android.Path, zipPrefix string,
 	flags []string) {

 	if zipPrefix != "" {
 		zipPrefix = "--zip-prefix " + zipPrefix
 	}
 	ctx.Build(pctx, android.BuildParams{
 		Rule:        aapt2CompileZipRule,
 		Description: "aapt2 compile zip",
 		Input:       zip,
 		Output:      flata,
 		Args: map[string]string{
 			"cFlags":       strings.Join(flags, " "),
 			"resZipDir":    android.PathForModuleOut(ctx, "aapt2", "reszip", flata.Base()).String(),
 			"zipSyncFlags": zipPrefix,
 		},
 	})
 }

 var aapt2LinkRule = pctx.AndroidStaticRule("aapt2Link",
 	blueprint.RuleParams{
 		Command: `$preamble` +
 			`${config.Aapt2Cmd} link -o $out $flags --proguard $proguardOptions ` +
 			`--output-text-symbols ${rTxt} $inFlags` +
 			`$postamble`,

 		CommandDeps: []string{
 			"${config.Aapt2Cmd}",
 			"${config.SoongZipCmd}",
 		},
 		Restat: true,
 	},
 	"flags", "inFlags", "proguardOptions", "rTxt", "extraPackages", "preamble", "postamble")

 var aapt2ExtractExtraPackagesRule = pctx.AndroidStaticRule("aapt2ExtractExtraPackages",
 	blueprint.RuleParams{
 		Command:     `${config.ExtractJarPackagesCmd} -i $in -o $out --prefix '--extra-packages '`,
 		CommandDeps: []string{"${config.ExtractJarPackagesCmd}"},
 		Restat:      true,
 	})

 var fileListToFileRule = pctx.AndroidStaticRule("fileListToFile",
 	blueprint.RuleParams{
 		Command:        `cp $out.rsp $out`,
 		Rspfile:        "$out.rsp",
 		RspfileContent: "$in",
 	})

 var mergeAssetsRule = pctx.AndroidStaticRule("mergeAssets",
 	blueprint.RuleParams{
 		Command:     `${config.MergeZipsCmd} ${out} ${in}`,
 		CommandDeps: []string{"${config.MergeZipsCmd}"},
 	})

 func aapt2Link(ctx android.ModuleContext,
 	packageRes, genJar, proguardOptions, rTxt android.WritablePath,
 	flags []string, deps android.Paths,
 	compiledRes, compiledOverlay, assetPackages android.Paths, splitPackages android.WritablePaths,
 	featureFlagsPaths android.Paths) {

 	var inFlags []string

 	if len(compiledRes) > 0 {
 		// Create a file that contains the list of all compiled resource file paths.
 		resFileList := android.PathForModuleOut(ctx, "aapt2", "res.list")
 		// Write out file lists to files
 		ctx.Build(pctx, android.BuildParams{
 			Rule:        fileListToFileRule,
 			Description: "resource file list",
 			Inputs:      compiledRes,
 			Output:      resFileList,
 		})

 		deps = append(deps, compiledRes...)
 		deps = append(deps, resFileList)
 		// aapt2 filepath arguments that start with "@" mean file-list files.
 		inFlags = append(inFlags, "@"+resFileList.String())
 	}

 	if len(compiledOverlay) > 0 {
 		// Compiled overlay files are processed the same way as compiled resources.
 		overlayFileList := android.PathForModuleOut(ctx, "aapt2", "overlay.list")
 		ctx.Build(pctx, android.BuildParams{
 			Rule:        fileListToFileRule,
 			Description: "overlay resource file list",
 			Inputs:      compiledOverlay,
 			Output:      overlayFileList,
 		})

 		deps = append(deps, compiledOverlay...)
 		deps = append(deps, overlayFileList)
 		// Compiled overlay files are passed over to aapt2 using -R option.
 		inFlags = append(inFlags, "-R", "@"+overlayFileList.String())
 	}

 	// Set auxiliary outputs as implicit outputs to establish correct dependency chains.
 	implicitOutputs := append(splitPackages, proguardOptions, rTxt)
 	linkOutput := packageRes

 	// AAPT2 ignores assets in overlays. Merge them after linking.
 	if len(assetPackages) > 0 {
 		linkOutput = android.PathForModuleOut(ctx, "aapt2", "package-res.apk")
 		inputZips := append(android.Paths{linkOutput}, assetPackages...)
 		ctx.Build(pctx, android.BuildParams{
 			Rule:        mergeAssetsRule,
 			Inputs:      inputZips,
 			Output:      packageRes,
 			Description: "merge assets from dependencies",
 		})
 	}

 	for _, featureFlagsPath := range featureFlagsPaths {
 		deps = append(deps, featureFlagsPath)
 		inFlags = append(inFlags, "--feature-flags", "@"+featureFlagsPath.String())
 	}

 	// Note the absence of splitPackages. The caller is supposed to compose and provide --split flag
 	// values via the flags parameter when it wants to split outputs.
 	// TODO(b/174509108): Perhaps we can process it in this func while keeping the code reasonably
 	// tidy.
 	args := map[string]string{
 		"flags":           strings.Join(flags, " "),
 		"inFlags":         strings.Join(inFlags, " "),
 		"proguardOptions": proguardOptions.String(),
 		"rTxt":            rTxt.String(),
 	}

 	if genJar != nil {
 		// Generating java source files from aapt2 was requested, use aapt2LinkAndGenRule and pass it
 		// genJar and genDir args.
 		genDir := android.PathForModuleGen(ctx, "aapt2", "R")
 		ctx.Variable(pctx, "aapt2GenDir", genDir.String())
 		ctx.Variable(pctx, "aapt2GenJar", genJar.String())
 		implicitOutputs = append(implicitOutputs, genJar)
 		args["preamble"] = `rm -rf $aapt2GenDir && `
 		args["postamble"] = `&& ${config.SoongZipCmd} -write_if_changed -jar -o $aapt2GenJar -C $aapt2GenDir -D $aapt2GenDir && ` +
 			`rm -rf $aapt2GenDir`
 		args["flags"] += " --java $aapt2GenDir"
 	}

 	ctx.Build(pctx, android.BuildParams{
 		Rule:            aapt2LinkRule,
 		Description:     "aapt2 link",
 		Implicits:       deps,
 		Output:          linkOutput,
 		ImplicitOutputs: implicitOutputs,
 		Args:            args,
 	})
 }

 // aapt2ExtractExtraPackages takes a srcjar generated by aapt2 or a classes jar generated by ResourceProcessorBusyBox
 // and converts it to a text file containing a list of --extra_package arguments for passing to Make modules so they
 // correctly generate R.java entries for packages provided by transitive dependencies.
 func aapt2ExtractExtraPackages(ctx android.ModuleContext, out android.WritablePath, in android.Path) {
 	ctx.Build(pctx, android.BuildParams{
 		Rule:        aapt2ExtractExtraPackagesRule,
 		Description: "aapt2 extract extra packages",
 		Input:       in,
 		Output:      out,
 	})
 }

 var aapt2ConvertRule = pctx.AndroidStaticRule("aapt2Convert",
 	blueprint.RuleParams{
 		Command: `${config.Aapt2Cmd} convert --enable-compact-entries ` +
 			`--output-format $format $in -o $out`,
 		CommandDeps: []string{"${config.Aapt2Cmd}"},
 	}, "format",
 )

 // Converts xml files and resource tables (resources.arsc) in the given jar/apk file to a proto
 // format. The proto definition is available at frameworks/base/tools/aapt2/Resources.proto.
 func aapt2Convert(ctx android.ModuleContext, out android.WritablePath, in android.Path, format string) {
 	ctx.Build(pctx, android.BuildParams{
 		Rule:        aapt2ConvertRule,
 		Input:       in,
 		Output:      out,
 		Description: "convert to " + format,
 		Args: map[string]string{
 			"format": format,
 		},
 	})
 }
	// 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.

	package java

	import (
	"path/filepath"
	"sort"
	"strconv"
	"strings"

	"github.com/google/blueprint"

	"android/soong/android"
	)

	func isPathValueResource(res android.Path) bool {
	subDir := filepath.Dir(res.String())
	subDir, lastDir := filepath.Split(subDir)
	return strings.HasPrefix(lastDir, "values")
	}

	// Convert input resource file path to output file path.
	// values-[config]/<file>.xml -> values-[config]_<file>.arsc.flat;
	// For other resource file, just replace the last "/" with "_" and add .flat extension.
	func pathToAapt2Path(ctx android.ModuleContext, res android.Path) android.WritablePath {

	name := res.Base()
	if isPathValueResource(res) {
	name = strings.TrimSuffix(name, ".xml") + ".arsc"
	}
	subDir := filepath.Dir(res.String())
	subDir, lastDir := filepath.Split(subDir)
	name = lastDir + "_" + name + ".flat"
	return android.PathForModuleOut(ctx, "aapt2", subDir, name)
	}

	// pathsToAapt2Paths Calls pathToAapt2Path on each entry of the given Paths, i.e. []Path.
	func pathsToAapt2Paths(ctx android.ModuleContext, resPaths android.Paths) android.WritablePaths {
	outPaths := make(android.WritablePaths, len(resPaths))

	for i, res := range resPaths {
	outPaths[i] = pathToAapt2Path(ctx, res)
	}

	return outPaths
	}

	// Shard resource files for efficiency. See aapt2Compile for details.
	const AAPT2_SHARD_SIZE = 100

	var aapt2CompileRule = pctx.AndroidStaticRule("aapt2Compile",
	blueprint.RuleParams{
	Command: `${config.Aapt2Cmd} compile -o $outDir $cFlags $in`,
	CommandDeps: []string{"${config.Aapt2Cmd}"},
	},
	"outDir", "cFlags")

	// aapt2Compile compiles resources and puts the results in the requested directory.
	func aapt2Compile(ctx android.ModuleContext, dir android.Path, paths android.Paths,
	flags []string, productToFilter string) android.WritablePaths {
	if productToFilter != "" && productToFilter != "default" {
	// --filter-product leaves only product-specific resources. Product-specific resources only exist
	// in value resources (values/*.xml), so filter value resource files only. Ignore other types of
	// resources as they don't need to be in product characteristics RRO (and they will cause aapt2
	// compile errors)
	filteredPaths := android.Paths{}
	for _, path := range paths {
	if isPathValueResource(path) {
	filteredPaths = append(filteredPaths, path)
	}
	}
	paths = filteredPaths
	flags = append([]string{"--filter-product " + productToFilter}, flags...)
	}

	// Shard the input paths so that they can be processed in parallel. If we shard them into too
	// small chunks, the additional cost of spinning up aapt2 outweighs the performance gain. The
	// current shard size, 100, seems to be a good balance between the added cost and the gain.
	// The aapt2 compile actions are trivially short, but each action in ninja takes on the order of
	// ~10 ms to run. frameworks/base/core/res/res has >10k resource files, so compiling each one
	// with an individual action could take 100 CPU seconds. Sharding them reduces the overhead of
	// starting actions by a factor of 100, at the expense of recompiling more files when one
	// changes. Since the individual compiles are trivial it's a good tradeoff.
	shards := android.ShardPaths(paths, AAPT2_SHARD_SIZE)

	ret := make(android.WritablePaths, 0, len(paths))

	for i, shard := range shards {
	// This should be kept in sync with pathToAapt2Path. The aapt2 compile command takes an
	// output directory path, but not output file paths. So, outPaths is just where we expect
	// the output files will be located.
	outPaths := pathsToAapt2Paths(ctx, shard)
	ret = append(ret, outPaths...)

	shardDesc := ""
	if i != 0 {
	shardDesc = " " + strconv.Itoa(i+1)
	}

	ctx.Build(pctx, android.BuildParams{
	Rule: aapt2CompileRule,
	Description: "aapt2 compile " + dir.String() + shardDesc,
	Inputs: shard,
	Outputs: outPaths,
	Args: map[string]string{
	// The aapt2 compile command takes an output directory path, but not output file paths.
	// outPaths specified above is only used for dependency management purposes. In order for
	// the outPaths values to match the actual outputs from aapt2, the dir parameter value
	// must be a common prefix path of the paths values, and the top-level path segment used
	// below, "aapt2", must always be kept in sync with the one in pathToAapt2Path.
	// TODO(b/174505750): Make this easier and robust to use.
	"outDir": android.PathForModuleOut(ctx, "aapt2", dir.String()).String(),
	"cFlags": strings.Join(flags, " "),
	},
	})
	}

	sort.Slice(ret, func(i, j int) bool {
	return ret[i].String() < ret[j].String()
	})
	return ret
	}

	var aapt2CompileZipRule = pctx.AndroidStaticRule("aapt2CompileZip",
	blueprint.RuleParams{
	Command: `${config.ZipSyncCmd} -d $resZipDir $zipSyncFlags $in && ` +
	`${config.Aapt2Cmd} compile -o $out $cFlags --dir $resZipDir`,
	CommandDeps: []string{
	"${config.Aapt2Cmd}",
	"${config.ZipSyncCmd}",
	},
	}, "cFlags", "resZipDir", "zipSyncFlags")

	// Unzips the given compressed file and compiles the resource source files in it. The zipPrefix
	// parameter points to the subdirectory in the zip file where the resource files are located.
	func aapt2CompileZip(ctx android.ModuleContext, flata android.WritablePath, zip android.Path, zipPrefix string,
	flags []string) {

	if zipPrefix != "" {
	zipPrefix = "--zip-prefix " + zipPrefix
	}
	ctx.Build(pctx, android.BuildParams{
	Rule: aapt2CompileZipRule,
	Description: "aapt2 compile zip",
	Input: zip,
	Output: flata,
	Args: map[string]string{
	"cFlags": strings.Join(flags, " "),
	"resZipDir": android.PathForModuleOut(ctx, "aapt2", "reszip", flata.Base()).String(),
	"zipSyncFlags": zipPrefix,
	},
	})
	}

	var aapt2LinkRule = pctx.AndroidStaticRule("aapt2Link",
	blueprint.RuleParams{
	Command: `$preamble` +
	`${config.Aapt2Cmd} link -o $out $flags --proguard $proguardOptions ` +
	`--output-text-symbols ${rTxt} $inFlags` +
	`$postamble`,

	CommandDeps: []string{
	"${config.Aapt2Cmd}",
	"${config.SoongZipCmd}",
	},
	Restat: true,
	},
	"flags", "inFlags", "proguardOptions", "rTxt", "extraPackages", "preamble", "postamble")

	var aapt2ExtractExtraPackagesRule = pctx.AndroidStaticRule("aapt2ExtractExtraPackages",
	blueprint.RuleParams{
	Command: `${config.ExtractJarPackagesCmd} -i $in -o $out --prefix '--extra-packages '`,
	CommandDeps: []string{"${config.ExtractJarPackagesCmd}"},
	Restat: true,
	})

	var fileListToFileRule = pctx.AndroidStaticRule("fileListToFile",
	blueprint.RuleParams{
	Command: `cp $out.rsp $out`,
	Rspfile: "$out.rsp",
	RspfileContent: "$in",
	})

	var mergeAssetsRule = pctx.AndroidStaticRule("mergeAssets",
	blueprint.RuleParams{
	Command: `${config.MergeZipsCmd} ${out} ${in}`,
	CommandDeps: []string{"${config.MergeZipsCmd}"},
	})

	func aapt2Link(ctx android.ModuleContext,
	packageRes, genJar, proguardOptions, rTxt android.WritablePath,
	flags []string, deps android.Paths,
	compiledRes, compiledOverlay, assetPackages android.Paths, splitPackages android.WritablePaths,
	featureFlagsPaths android.Paths) {

	var inFlags []string

	if len(compiledRes) > 0 {
	// Create a file that contains the list of all compiled resource file paths.
	resFileList := android.PathForModuleOut(ctx, "aapt2", "res.list")
	// Write out file lists to files
	ctx.Build(pctx, android.BuildParams{
	Rule: fileListToFileRule,
	Description: "resource file list",
	Inputs: compiledRes,
	Output: resFileList,
	})

	deps = append(deps, compiledRes...)
	deps = append(deps, resFileList)
	// aapt2 filepath arguments that start with "@" mean file-list files.
	inFlags = append(inFlags, "@"+resFileList.String())
	}

	if len(compiledOverlay) > 0 {
	// Compiled overlay files are processed the same way as compiled resources.
	overlayFileList := android.PathForModuleOut(ctx, "aapt2", "overlay.list")
	ctx.Build(pctx, android.BuildParams{
	Rule: fileListToFileRule,
	Description: "overlay resource file list",
	Inputs: compiledOverlay,
	Output: overlayFileList,
	})

	deps = append(deps, compiledOverlay...)
	deps = append(deps, overlayFileList)
	// Compiled overlay files are passed over to aapt2 using -R option.
	inFlags = append(inFlags, "-R", "@"+overlayFileList.String())
	}

	// Set auxiliary outputs as implicit outputs to establish correct dependency chains.
	implicitOutputs := append(splitPackages, proguardOptions, rTxt)
	linkOutput := packageRes

	// AAPT2 ignores assets in overlays. Merge them after linking.
	if len(assetPackages) > 0 {
	linkOutput = android.PathForModuleOut(ctx, "aapt2", "package-res.apk")
	inputZips := append(android.Paths{linkOutput}, assetPackages...)
	ctx.Build(pctx, android.BuildParams{
	Rule: mergeAssetsRule,
	Inputs: inputZips,
	Output: packageRes,
	Description: "merge assets from dependencies",
	})
	}

	for _, featureFlagsPath := range featureFlagsPaths {
	deps = append(deps, featureFlagsPath)
	inFlags = append(inFlags, "--feature-flags", "@"+featureFlagsPath.String())
	}

	// Note the absence of splitPackages. The caller is supposed to compose and provide --split flag
	// values via the flags parameter when it wants to split outputs.
	// TODO(b/174509108): Perhaps we can process it in this func while keeping the code reasonably
	// tidy.
	args := map[string]string{
	"flags": strings.Join(flags, " "),
	"inFlags": strings.Join(inFlags, " "),
	"proguardOptions": proguardOptions.String(),
	"rTxt": rTxt.String(),
	}

	if genJar != nil {
	// Generating java source files from aapt2 was requested, use aapt2LinkAndGenRule and pass it
	// genJar and genDir args.
	genDir := android.PathForModuleGen(ctx, "aapt2", "R")
	ctx.Variable(pctx, "aapt2GenDir", genDir.String())
	ctx.Variable(pctx, "aapt2GenJar", genJar.String())
	implicitOutputs = append(implicitOutputs, genJar)
	args["preamble"] = `rm -rf $aapt2GenDir && `
	args["postamble"] = `&& ${config.SoongZipCmd} -write_if_changed -jar -o $aapt2GenJar -C $aapt2GenDir -D $aapt2GenDir && ` +
	`rm -rf $aapt2GenDir`
	args["flags"] += " --java $aapt2GenDir"
	}

	ctx.Build(pctx, android.BuildParams{
	Rule: aapt2LinkRule,
	Description: "aapt2 link",
	Implicits: deps,
	Output: linkOutput,
	ImplicitOutputs: implicitOutputs,
	Args: args,
	})
	}

	// aapt2ExtractExtraPackages takes a srcjar generated by aapt2 or a classes jar generated by ResourceProcessorBusyBox
	// and converts it to a text file containing a list of --extra_package arguments for passing to Make modules so they
	// correctly generate R.java entries for packages provided by transitive dependencies.
	func aapt2ExtractExtraPackages(ctx android.ModuleContext, out android.WritablePath, in android.Path) {
	ctx.Build(pctx, android.BuildParams{
	Rule: aapt2ExtractExtraPackagesRule,
	Description: "aapt2 extract extra packages",
	Input: in,
	Output: out,
	})
	}

	var aapt2ConvertRule = pctx.AndroidStaticRule("aapt2Convert",
	blueprint.RuleParams{
	Command: `${config.Aapt2Cmd} convert --enable-compact-entries ` +
	`--output-format $format $in -o $out`,
	CommandDeps: []string{"${config.Aapt2Cmd}"},
	}, "format",
	)

	// Converts xml files and resource tables (resources.arsc) in the given jar/apk file to a proto
	// format. The proto definition is available at frameworks/base/tools/aapt2/Resources.proto.
	func aapt2Convert(ctx android.ModuleContext, out android.WritablePath, in android.Path, format string) {
	ctx.Build(pctx, android.BuildParams{
	Rule: aapt2ConvertRule,
	Input: in,
	Output: out,
	Description: "convert to " + format,
	Args: map[string]string{
	"format": format,
	},
	})
	}