android/packaging.go - SHIFTPHONES/android_build_soong - Gitiles

 // Copyright 2020 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 android

 import (
 	"fmt"
 	"path/filepath"
 	"strings"

 	"github.com/google/blueprint"
 	"github.com/google/blueprint/proptools"
 )

 // PackagingSpec abstracts a request to place a built artifact at a certain path in a package. A
 // package can be the traditional <partition>.img, but isn't limited to those. Other examples could
 // be a new filesystem image that is a subset of system.img (e.g. for an Android-like mini OS
 // running on a VM), or a zip archive for some of the host tools.
 type PackagingSpec struct {
 	// Path relative to the root of the package
 	relPathInPackage string

 	// The path to the built artifact
 	srcPath Path

 	// If this is not empty, then relPathInPackage should be a symlink to this target. (Then
 	// srcPath is of course ignored.)
 	symlinkTarget string

 	// Whether relPathInPackage should be marked as executable or not
 	executable bool

 	effectiveLicenseFiles *Paths

 	partition string

 	// Whether this packaging spec represents an installation of the srcPath (i.e. this struct
 	// is created via InstallFile or InstallSymlink) or a simple packaging (i.e. created via
 	// PackageFile).
 	skipInstall bool

 	// Paths of aconfig files for the built artifact
 	aconfigPaths *Paths

 	// ArchType of the module which produced this packaging spec
 	archType ArchType
 }

 func (p *PackagingSpec) Equals(other *PackagingSpec) bool {
 	if other == nil {
 		return false
 	}
 	if p.relPathInPackage != other.relPathInPackage {
 		return false
 	}
 	if p.srcPath != other.srcPath || p.symlinkTarget != other.symlinkTarget {
 		return false
 	}
 	if p.executable != other.executable {
 		return false
 	}
 	if p.partition != other.partition {
 		return false
 	}
 	return true
 }

 // Get file name of installed package
 func (p *PackagingSpec) FileName() string {
 	if p.relPathInPackage != "" {
 		return filepath.Base(p.relPathInPackage)
 	}

 	return ""
 }

 // Path relative to the root of the package
 func (p *PackagingSpec) RelPathInPackage() string {
 	return p.relPathInPackage
 }

 func (p *PackagingSpec) SetRelPathInPackage(relPathInPackage string) {
 	p.relPathInPackage = relPathInPackage
 }

 func (p *PackagingSpec) EffectiveLicenseFiles() Paths {
 	if p.effectiveLicenseFiles == nil {
 		return Paths{}
 	}
 	return *p.effectiveLicenseFiles
 }

 func (p *PackagingSpec) Partition() string {
 	return p.partition
 }

 func (p *PackagingSpec) SkipInstall() bool {
 	return p.skipInstall
 }

 // Paths of aconfig files for the built artifact
 func (p *PackagingSpec) GetAconfigPaths() Paths {
 	return *p.aconfigPaths
 }

 type PackageModule interface {
 	Module
 	packagingBase() *PackagingBase

 	// AddDeps adds dependencies to the `deps` modules. This should be called in DepsMutator.
 	// When adding the dependencies, depTag is used as the tag. If `deps` modules are meant to
 	// be copied to a zip in CopyDepsToZip, `depTag` should implement PackagingItem marker interface.
 	AddDeps(ctx BottomUpMutatorContext, depTag blueprint.DependencyTag)

 	// GatherPackagingSpecs gathers PackagingSpecs of transitive dependencies.
 	GatherPackagingSpecs(ctx ModuleContext) map[string]PackagingSpec
 	GatherPackagingSpecsWithFilter(ctx ModuleContext, filter func(PackagingSpec) bool) map[string]PackagingSpec

 	// CopyDepsToZip zips the built artifacts of the dependencies into the given zip file and
 	// returns zip entries in it. This is expected to be called in GenerateAndroidBuildActions,
 	// followed by a build rule that unzips it and creates the final output (img, zip, tar.gz,
 	// etc.) from the extracted files
 	CopyDepsToZip(ctx ModuleContext, specs map[string]PackagingSpec, zipOut WritablePath) []string
 }

 // PackagingBase provides basic functionality for packaging dependencies. A module is expected to
 // include this struct and call InitPackageModule.
 type PackagingBase struct {
 	properties PackagingProperties

 	// Allows this module to skip missing dependencies. In most cases, this is not required, but
 	// for rare cases like when there's a dependency to a module which exists in certain repo
 	// checkouts, this is needed.
 	IgnoreMissingDependencies bool

 	// If this is set to true by a module type inheriting PackagingBase, the deps property
 	// collects the first target only even with compile_multilib: true.
 	DepsCollectFirstTargetOnly bool
 }

 type depsProperty struct {
 	// Modules to include in this package
 	Deps proptools.Configurable[[]string] `android:"arch_variant"`
 }

 type packagingMultilibProperties struct {
 	First    depsProperty `android:"arch_variant"`
 	Common   depsProperty `android:"arch_variant"`
 	Lib32    depsProperty `android:"arch_variant"`
 	Lib64    depsProperty `android:"arch_variant"`
 	Both     depsProperty `android:"arch_variant"`
 	Prefer32 depsProperty `android:"arch_variant"`
 }

 type packagingArchProperties struct {
 	Arm64  depsProperty
 	Arm    depsProperty
 	X86_64 depsProperty
 	X86    depsProperty
 }

 type PackagingProperties struct {
 	Deps     proptools.Configurable[[]string] `android:"arch_variant"`
 	Multilib packagingMultilibProperties      `android:"arch_variant"`
 	Arch     packagingArchProperties
 }

 func InitPackageModule(p PackageModule) {
 	base := p.packagingBase()
 	p.AddProperties(&base.properties)
 }

 func (p *PackagingBase) packagingBase() *PackagingBase {
 	return p
 }

 // From deps and multilib.*.deps, select the dependencies that are for the given arch deps is for
 // the current archicture when this module is not configured for multi target. When configured for
 // multi target, deps is selected for each of the targets and is NOT selected for the current
 // architecture which would be Common.
 func (p *PackagingBase) getDepsForArch(ctx BaseModuleContext, arch ArchType) []string {
 	get := func(prop proptools.Configurable[[]string]) []string {
 		return prop.GetOrDefault(ctx, nil)
 	}

 	var ret []string
 	if arch == ctx.Target().Arch.ArchType && len(ctx.MultiTargets()) == 0 {
 		ret = append(ret, get(p.properties.Deps)...)
 	} else if arch.Multilib == "lib32" {
 		ret = append(ret, get(p.properties.Multilib.Lib32.Deps)...)
 		// multilib.prefer32.deps are added for lib32 only when they support 32-bit arch
 		for _, dep := range get(p.properties.Multilib.Prefer32.Deps) {
 			if checkIfOtherModuleSupportsLib32(ctx, dep) {
 				ret = append(ret, dep)
 			}
 		}
 	} else if arch.Multilib == "lib64" {
 		ret = append(ret, get(p.properties.Multilib.Lib64.Deps)...)
 		// multilib.prefer32.deps are added for lib64 only when they don't support 32-bit arch
 		for _, dep := range get(p.properties.Multilib.Prefer32.Deps) {
 			if !checkIfOtherModuleSupportsLib32(ctx, dep) {
 				ret = append(ret, dep)
 			}
 		}
 	} else if arch == Common {
 		ret = append(ret, get(p.properties.Multilib.Common.Deps)...)
 	}

 	if p.DepsCollectFirstTargetOnly {
 		if len(get(p.properties.Multilib.First.Deps)) > 0 {
 			ctx.PropertyErrorf("multilib.first.deps", "not supported. use \"deps\" instead")
 		}
 		for i, t := range ctx.MultiTargets() {
 			if t.Arch.ArchType == arch {
 				ret = append(ret, get(p.properties.Multilib.Both.Deps)...)
 				if i == 0 {
 					ret = append(ret, get(p.properties.Deps)...)
 				}
 			}
 		}
 	} else {
 		if len(get(p.properties.Multilib.Both.Deps)) > 0 {
 			ctx.PropertyErrorf("multilib.both.deps", "not supported. use \"deps\" instead")
 		}
 		for i, t := range ctx.MultiTargets() {
 			if t.Arch.ArchType == arch {
 				ret = append(ret, get(p.properties.Deps)...)
 				if i == 0 {
 					ret = append(ret, get(p.properties.Multilib.First.Deps)...)
 				}
 			}
 		}
 	}

 	if ctx.Arch().ArchType == Common {
 		switch arch {
 		case Arm64:
 			ret = append(ret, get(p.properties.Arch.Arm64.Deps)...)
 		case Arm:
 			ret = append(ret, get(p.properties.Arch.Arm.Deps)...)
 		case X86_64:
 			ret = append(ret, get(p.properties.Arch.X86_64.Deps)...)
 		case X86:
 			ret = append(ret, get(p.properties.Arch.X86.Deps)...)
 		}
 	}

 	return FirstUniqueStrings(ret)
 }

 func getSupportedTargets(ctx BaseModuleContext) []Target {
 	var ret []Target
 	// The current and the common OS targets are always supported
 	ret = append(ret, ctx.Target())
 	if ctx.Arch().ArchType != Common {
 		ret = append(ret, Target{Os: ctx.Os(), Arch: Arch{ArchType: Common}})
 	}
 	// If this module is configured for multi targets, those should be supported as well
 	ret = append(ret, ctx.MultiTargets()...)
 	return ret
 }

 // getLib32Target returns the 32-bit target from the list of targets this module supports. If this
 // module doesn't support 32-bit target, nil is returned.
 func getLib32Target(ctx BaseModuleContext) *Target {
 	for _, t := range getSupportedTargets(ctx) {
 		if t.Arch.ArchType.Multilib == "lib32" {
 			return &t
 		}
 	}
 	return nil
 }

 // checkIfOtherModuleSUpportsLib32 returns true if 32-bit variant of dep exists.
 func checkIfOtherModuleSupportsLib32(ctx BaseModuleContext, dep string) bool {
 	t := getLib32Target(ctx)
 	if t == nil {
 		// This packaging module doesn't support 32bit. No point of checking if dep supports 32-bit
 		// or not.
 		return false
 	}
 	return ctx.OtherModuleFarDependencyVariantExists(t.Variations(), dep)
 }

 // PackagingItem is a marker interface for dependency tags.
 // Direct dependencies with a tag implementing PackagingItem are packaged in CopyDepsToZip().
 type PackagingItem interface {
 	// IsPackagingItem returns true if the dep is to be packaged
 	IsPackagingItem() bool
 }

 // DepTag provides default implementation of PackagingItem interface.
 // PackagingBase-derived modules can define their own dependency tag by embedding this, which
 // can be passed to AddDeps() or AddDependencies().
 type PackagingItemAlwaysDepTag struct {
 }

 // IsPackagingItem returns true if the dep is to be packaged
 func (PackagingItemAlwaysDepTag) IsPackagingItem() bool {
 	return true
 }

 // See PackageModule.AddDeps
 func (p *PackagingBase) AddDeps(ctx BottomUpMutatorContext, depTag blueprint.DependencyTag) {
 	for _, t := range getSupportedTargets(ctx) {
 		for _, dep := range p.getDepsForArch(ctx, t.Arch.ArchType) {
 			if p.IgnoreMissingDependencies && !ctx.OtherModuleExists(dep) {
 				continue
 			}
 			ctx.AddFarVariationDependencies(t.Variations(), depTag, dep)
 		}
 	}
 }

 func (p *PackagingBase) GatherPackagingSpecsWithFilter(ctx ModuleContext, filter func(PackagingSpec) bool) map[string]PackagingSpec {
 	m := make(map[string]PackagingSpec)

 	var arches []ArchType
 	for _, target := range getSupportedTargets(ctx) {
 		arches = append(arches, target.Arch.ArchType)
 	}

 	// filter out packaging specs for unsupported architecture
 	filterArch := func(ps PackagingSpec) bool {
 		for _, arch := range arches {
 			if arch == ps.archType {
 				return true
 			}
 		}
 		return false
 	}

 	ctx.VisitDirectDeps(func(child Module) {
 		if pi, ok := ctx.OtherModuleDependencyTag(child).(PackagingItem); !ok || !pi.IsPackagingItem() {
 			return
 		}
 		for _, ps := range child.TransitivePackagingSpecs() {
 			if !filterArch(ps) {
 				continue
 			}

 			if filter != nil {
 				if !filter(ps) {
 					continue
 				}
 			}
 			dstPath := ps.relPathInPackage
 			if existingPs, ok := m[dstPath]; ok {
 				if !existingPs.Equals(&ps) {
 					ctx.ModuleErrorf("packaging conflict at %v:\n%v\n%v", dstPath, existingPs, ps)
 				}
 				continue
 			}

 			m[dstPath] = ps
 		}
 	})
 	return m
 }

 // See PackageModule.GatherPackagingSpecs
 func (p *PackagingBase) GatherPackagingSpecs(ctx ModuleContext) map[string]PackagingSpec {
 	return p.GatherPackagingSpecsWithFilter(ctx, nil)
 }

 // CopySpecsToDir is a helper that will add commands to the rule builder to copy the PackagingSpec
 // entries into the specified directory.
 func (p *PackagingBase) CopySpecsToDir(ctx ModuleContext, builder *RuleBuilder, specs map[string]PackagingSpec, dir WritablePath) (entries []string) {
 	if len(specs) == 0 {
 		return entries
 	}
 	seenDir := make(map[string]bool)
 	preparerPath := PathForModuleOut(ctx, "preparer.sh")
 	cmd := builder.Command().Tool(preparerPath)
 	var sb strings.Builder
 	sb.WriteString("set -e\n")
 	for _, k := range SortedKeys(specs) {
 		ps := specs[k]
 		destPath := filepath.Join(dir.String(), ps.relPathInPackage)
 		destDir := filepath.Dir(destPath)
 		entries = append(entries, ps.relPathInPackage)
 		if _, ok := seenDir[destDir]; !ok {
 			seenDir[destDir] = true
 			sb.WriteString(fmt.Sprintf("mkdir -p %s\n", destDir))
 		}
 		if ps.symlinkTarget == "" {
 			cmd.Implicit(ps.srcPath)
 			sb.WriteString(fmt.Sprintf("cp %s %s\n", ps.srcPath, destPath))
 		} else {
 			sb.WriteString(fmt.Sprintf("ln -sf %s %s\n", ps.symlinkTarget, destPath))
 		}
 		if ps.executable {
 			sb.WriteString(fmt.Sprintf("chmod a+x %s\n", destPath))
 		}
 	}

 	WriteExecutableFileRuleVerbatim(ctx, preparerPath, sb.String())

 	return entries
 }

 // See PackageModule.CopyDepsToZip
 func (p *PackagingBase) CopyDepsToZip(ctx ModuleContext, specs map[string]PackagingSpec, zipOut WritablePath) (entries []string) {
 	builder := NewRuleBuilder(pctx, ctx)

 	dir := PathForModuleOut(ctx, ".zip")
 	builder.Command().Text("rm").Flag("-rf").Text(dir.String())
 	builder.Command().Text("mkdir").Flag("-p").Text(dir.String())
 	entries = p.CopySpecsToDir(ctx, builder, specs, dir)

 	builder.Command().
 		BuiltTool("soong_zip").
 		FlagWithOutput("-o ", zipOut).
 		FlagWithArg("-C ", dir.String()).
 		Flag("-L 0"). // no compression because this will be unzipped soon
 		FlagWithArg("-D ", dir.String())
 	builder.Command().Text("rm").Flag("-rf").Text(dir.String())

 	builder.Build("zip_deps", fmt.Sprintf("Zipping deps for %s", ctx.ModuleName()))
 	return entries
 }
	// Copyright 2020 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 android

	import (
	"fmt"
	"path/filepath"
	"strings"

	"github.com/google/blueprint"
	"github.com/google/blueprint/proptools"
	)

	// PackagingSpec abstracts a request to place a built artifact at a certain path in a package. A
	// package can be the traditional <partition>.img, but isn't limited to those. Other examples could
	// be a new filesystem image that is a subset of system.img (e.g. for an Android-like mini OS
	// running on a VM), or a zip archive for some of the host tools.
	type PackagingSpec struct {
	// Path relative to the root of the package
	relPathInPackage string

	// The path to the built artifact
	srcPath Path

	// If this is not empty, then relPathInPackage should be a symlink to this target. (Then
	// srcPath is of course ignored.)
	symlinkTarget string

	// Whether relPathInPackage should be marked as executable or not
	executable bool

	effectiveLicenseFiles *Paths

	partition string

	// Whether this packaging spec represents an installation of the srcPath (i.e. this struct
	// is created via InstallFile or InstallSymlink) or a simple packaging (i.e. created via
	// PackageFile).
	skipInstall bool

	// Paths of aconfig files for the built artifact
	aconfigPaths *Paths

	// ArchType of the module which produced this packaging spec
	archType ArchType
	}

	func (p PackagingSpec) Equals(other PackagingSpec) bool {
	if other == nil {
	return false
	}
	if p.relPathInPackage != other.relPathInPackage {
	return false
	}
	if p.srcPath != other.srcPath \|\| p.symlinkTarget != other.symlinkTarget {
	return false
	}
	if p.executable != other.executable {
	return false
	}
	if p.partition != other.partition {
	return false
	}
	return true
	}

	// Get file name of installed package
	func (p *PackagingSpec) FileName() string {
	if p.relPathInPackage != "" {
	return filepath.Base(p.relPathInPackage)
	}

	return ""
	}

	// Path relative to the root of the package
	func (p *PackagingSpec) RelPathInPackage() string {
	return p.relPathInPackage
	}

	func (p *PackagingSpec) SetRelPathInPackage(relPathInPackage string) {
	p.relPathInPackage = relPathInPackage
	}

	func (p *PackagingSpec) EffectiveLicenseFiles() Paths {
	if p.effectiveLicenseFiles == nil {
	return Paths{}
	}
	return *p.effectiveLicenseFiles
	}

	func (p *PackagingSpec) Partition() string {
	return p.partition
	}

	func (p *PackagingSpec) SkipInstall() bool {
	return p.skipInstall
	}

	// Paths of aconfig files for the built artifact
	func (p *PackagingSpec) GetAconfigPaths() Paths {
	return *p.aconfigPaths
	}

	type PackageModule interface {
	Module
	packagingBase() *PackagingBase

	// AddDeps adds dependencies to the `deps` modules. This should be called in DepsMutator.
	// When adding the dependencies, depTag is used as the tag. If `deps` modules are meant to
	// be copied to a zip in CopyDepsToZip, `depTag` should implement PackagingItem marker interface.
	AddDeps(ctx BottomUpMutatorContext, depTag blueprint.DependencyTag)

	// GatherPackagingSpecs gathers PackagingSpecs of transitive dependencies.
	GatherPackagingSpecs(ctx ModuleContext) map[string]PackagingSpec
	GatherPackagingSpecsWithFilter(ctx ModuleContext, filter func(PackagingSpec) bool) map[string]PackagingSpec

	// CopyDepsToZip zips the built artifacts of the dependencies into the given zip file and
	// returns zip entries in it. This is expected to be called in GenerateAndroidBuildActions,
	// followed by a build rule that unzips it and creates the final output (img, zip, tar.gz,
	// etc.) from the extracted files
	CopyDepsToZip(ctx ModuleContext, specs map[string]PackagingSpec, zipOut WritablePath) []string
	}

	// PackagingBase provides basic functionality for packaging dependencies. A module is expected to
	// include this struct and call InitPackageModule.
	type PackagingBase struct {
	properties PackagingProperties

	// Allows this module to skip missing dependencies. In most cases, this is not required, but
	// for rare cases like when there's a dependency to a module which exists in certain repo
	// checkouts, this is needed.
	IgnoreMissingDependencies bool

	// If this is set to true by a module type inheriting PackagingBase, the deps property
	// collects the first target only even with compile_multilib: true.
	DepsCollectFirstTargetOnly bool
	}

	type depsProperty struct {
	// Modules to include in this package
	Deps proptools.Configurable[[]string] `android:"arch_variant"`
	}

	type packagingMultilibProperties struct {
	First depsProperty `android:"arch_variant"`
	Common depsProperty `android:"arch_variant"`
	Lib32 depsProperty `android:"arch_variant"`
	Lib64 depsProperty `android:"arch_variant"`
	Both depsProperty `android:"arch_variant"`
	Prefer32 depsProperty `android:"arch_variant"`
	}

	type packagingArchProperties struct {
	Arm64 depsProperty
	Arm depsProperty
	X86_64 depsProperty
	X86 depsProperty
	}

	type PackagingProperties struct {
	Deps proptools.Configurable[[]string] `android:"arch_variant"`
	Multilib packagingMultilibProperties `android:"arch_variant"`
	Arch packagingArchProperties
	}

	func InitPackageModule(p PackageModule) {
	base := p.packagingBase()
	p.AddProperties(&base.properties)
	}

	func (p PackagingBase) packagingBase() PackagingBase {
	return p
	}

	// From deps and multilib.*.deps, select the dependencies that are for the given arch deps is for
	// the current archicture when this module is not configured for multi target. When configured for
	// multi target, deps is selected for each of the targets and is NOT selected for the current
	// architecture which would be Common.
	func (p *PackagingBase) getDepsForArch(ctx BaseModuleContext, arch ArchType) []string {
	get := func(prop proptools.Configurable[[]string]) []string {
	return prop.GetOrDefault(ctx, nil)
	}

	var ret []string
	if arch == ctx.Target().Arch.ArchType && len(ctx.MultiTargets()) == 0 {
	ret = append(ret, get(p.properties.Deps)...)
	} else if arch.Multilib == "lib32" {
	ret = append(ret, get(p.properties.Multilib.Lib32.Deps)...)
	// multilib.prefer32.deps are added for lib32 only when they support 32-bit arch
	for _, dep := range get(p.properties.Multilib.Prefer32.Deps) {
	if checkIfOtherModuleSupportsLib32(ctx, dep) {
	ret = append(ret, dep)
	}
	}
	} else if arch.Multilib == "lib64" {
	ret = append(ret, get(p.properties.Multilib.Lib64.Deps)...)
	// multilib.prefer32.deps are added for lib64 only when they don't support 32-bit arch
	for _, dep := range get(p.properties.Multilib.Prefer32.Deps) {
	if !checkIfOtherModuleSupportsLib32(ctx, dep) {
	ret = append(ret, dep)
	}
	}
	} else if arch == Common {
	ret = append(ret, get(p.properties.Multilib.Common.Deps)...)
	}

	if p.DepsCollectFirstTargetOnly {
	if len(get(p.properties.Multilib.First.Deps)) > 0 {
	ctx.PropertyErrorf("multilib.first.deps", "not supported. use \"deps\" instead")
	}
	for i, t := range ctx.MultiTargets() {
	if t.Arch.ArchType == arch {
	ret = append(ret, get(p.properties.Multilib.Both.Deps)...)
	if i == 0 {
	ret = append(ret, get(p.properties.Deps)...)
	}
	}
	}
	} else {
	if len(get(p.properties.Multilib.Both.Deps)) > 0 {
	ctx.PropertyErrorf("multilib.both.deps", "not supported. use \"deps\" instead")
	}
	for i, t := range ctx.MultiTargets() {
	if t.Arch.ArchType == arch {
	ret = append(ret, get(p.properties.Deps)...)
	if i == 0 {
	ret = append(ret, get(p.properties.Multilib.First.Deps)...)
	}
	}
	}
	}

	if ctx.Arch().ArchType == Common {
	switch arch {
	case Arm64:
	ret = append(ret, get(p.properties.Arch.Arm64.Deps)...)
	case Arm:
	ret = append(ret, get(p.properties.Arch.Arm.Deps)...)
	case X86_64:
	ret = append(ret, get(p.properties.Arch.X86_64.Deps)...)
	case X86:
	ret = append(ret, get(p.properties.Arch.X86.Deps)...)
	}
	}

	return FirstUniqueStrings(ret)
	}

	func getSupportedTargets(ctx BaseModuleContext) []Target {
	var ret []Target
	// The current and the common OS targets are always supported
	ret = append(ret, ctx.Target())
	if ctx.Arch().ArchType != Common {
	ret = append(ret, Target{Os: ctx.Os(), Arch: Arch{ArchType: Common}})
	}
	// If this module is configured for multi targets, those should be supported as well
	ret = append(ret, ctx.MultiTargets()...)
	return ret
	}

	// getLib32Target returns the 32-bit target from the list of targets this module supports. If this
	// module doesn't support 32-bit target, nil is returned.
	func getLib32Target(ctx BaseModuleContext) *Target {
	for _, t := range getSupportedTargets(ctx) {
	if t.Arch.ArchType.Multilib == "lib32" {
	return &t
	}
	}
	return nil
	}

	// checkIfOtherModuleSUpportsLib32 returns true if 32-bit variant of dep exists.
	func checkIfOtherModuleSupportsLib32(ctx BaseModuleContext, dep string) bool {
	t := getLib32Target(ctx)
	if t == nil {
	// This packaging module doesn't support 32bit. No point of checking if dep supports 32-bit
	// or not.
	return false
	}
	return ctx.OtherModuleFarDependencyVariantExists(t.Variations(), dep)
	}

	// PackagingItem is a marker interface for dependency tags.
	// Direct dependencies with a tag implementing PackagingItem are packaged in CopyDepsToZip().
	type PackagingItem interface {
	// IsPackagingItem returns true if the dep is to be packaged
	IsPackagingItem() bool
	}

	// DepTag provides default implementation of PackagingItem interface.
	// PackagingBase-derived modules can define their own dependency tag by embedding this, which
	// can be passed to AddDeps() or AddDependencies().
	type PackagingItemAlwaysDepTag struct {
	}

	// IsPackagingItem returns true if the dep is to be packaged
	func (PackagingItemAlwaysDepTag) IsPackagingItem() bool {
	return true
	}

	// See PackageModule.AddDeps
	func (p *PackagingBase) AddDeps(ctx BottomUpMutatorContext, depTag blueprint.DependencyTag) {
	for _, t := range getSupportedTargets(ctx) {
	for _, dep := range p.getDepsForArch(ctx, t.Arch.ArchType) {
	if p.IgnoreMissingDependencies && !ctx.OtherModuleExists(dep) {
	continue
	}
	ctx.AddFarVariationDependencies(t.Variations(), depTag, dep)
	}
	}
	}

	func (p *PackagingBase) GatherPackagingSpecsWithFilter(ctx ModuleContext, filter func(PackagingSpec) bool) map[string]PackagingSpec {
	m := make(map[string]PackagingSpec)

	var arches []ArchType
	for _, target := range getSupportedTargets(ctx) {
	arches = append(arches, target.Arch.ArchType)
	}

	// filter out packaging specs for unsupported architecture
	filterArch := func(ps PackagingSpec) bool {
	for _, arch := range arches {
	if arch == ps.archType {
	return true
	}
	}
	return false
	}

	ctx.VisitDirectDeps(func(child Module) {
	if pi, ok := ctx.OtherModuleDependencyTag(child).(PackagingItem); !ok \|\| !pi.IsPackagingItem() {
	return
	}
	for _, ps := range child.TransitivePackagingSpecs() {
	if !filterArch(ps) {
	continue
	}

	if filter != nil {
	if !filter(ps) {
	continue
	}
	}
	dstPath := ps.relPathInPackage
	if existingPs, ok := m[dstPath]; ok {
	if !existingPs.Equals(&ps) {
	ctx.ModuleErrorf("packaging conflict at %v:\n%v\n%v", dstPath, existingPs, ps)
	}
	continue
	}

	m[dstPath] = ps
	}
	})
	return m
	}

	// See PackageModule.GatherPackagingSpecs
	func (p *PackagingBase) GatherPackagingSpecs(ctx ModuleContext) map[string]PackagingSpec {
	return p.GatherPackagingSpecsWithFilter(ctx, nil)
	}

	// CopySpecsToDir is a helper that will add commands to the rule builder to copy the PackagingSpec
	// entries into the specified directory.
	func (p PackagingBase) CopySpecsToDir(ctx ModuleContext, builder RuleBuilder, specs map[string]PackagingSpec, dir WritablePath) (entries []string) {
	if len(specs) == 0 {
	return entries
	}
	seenDir := make(map[string]bool)
	preparerPath := PathForModuleOut(ctx, "preparer.sh")
	cmd := builder.Command().Tool(preparerPath)
	var sb strings.Builder
	sb.WriteString("set -e\n")
	for _, k := range SortedKeys(specs) {
	ps := specs[k]
	destPath := filepath.Join(dir.String(), ps.relPathInPackage)
	destDir := filepath.Dir(destPath)
	entries = append(entries, ps.relPathInPackage)
	if _, ok := seenDir[destDir]; !ok {
	seenDir[destDir] = true
	sb.WriteString(fmt.Sprintf("mkdir -p %s\n", destDir))
	}
	if ps.symlinkTarget == "" {
	cmd.Implicit(ps.srcPath)
	sb.WriteString(fmt.Sprintf("cp %s %s\n", ps.srcPath, destPath))
	} else {
	sb.WriteString(fmt.Sprintf("ln -sf %s %s\n", ps.symlinkTarget, destPath))
	}
	if ps.executable {
	sb.WriteString(fmt.Sprintf("chmod a+x %s\n", destPath))
	}
	}

	WriteExecutableFileRuleVerbatim(ctx, preparerPath, sb.String())

	return entries
	}

	// See PackageModule.CopyDepsToZip
	func (p *PackagingBase) CopyDepsToZip(ctx ModuleContext, specs map[string]PackagingSpec, zipOut WritablePath) (entries []string) {
	builder := NewRuleBuilder(pctx, ctx)

	dir := PathForModuleOut(ctx, ".zip")
	builder.Command().Text("rm").Flag("-rf").Text(dir.String())
	builder.Command().Text("mkdir").Flag("-p").Text(dir.String())
	entries = p.CopySpecsToDir(ctx, builder, specs, dir)

	builder.Command().
	BuiltTool("soong_zip").
	FlagWithOutput("-o ", zipOut).
	FlagWithArg("-C ", dir.String()).
	Flag("-L 0"). // no compression because this will be unzipped soon
	FlagWithArg("-D ", dir.String())
	builder.Command().Text("rm").Flag("-rf").Text(dir.String())

	builder.Build("zip_deps", fmt.Sprintf("Zipping deps for %s", ctx.ModuleName()))
	return entries
	}