android/module.go

// Copyright 2015 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/pathtools"
)

var (
	DeviceSharedLibrary = "shared_library"
	DeviceStaticLibrary = "static_library"
	DeviceExecutable    = "executable"
	HostSharedLibrary   = "host_shared_library"
	HostStaticLibrary   = "host_static_library"
	HostExecutable      = "host_executable"
)

type BuildParams struct {
	Rule            blueprint.Rule
	Deps            blueprint.Deps
	Depfile         WritablePath
	Description     string
	Output          WritablePath
	Outputs         WritablePaths
	ImplicitOutput  WritablePath
	ImplicitOutputs WritablePaths
	Input           Path
	Inputs          Paths
	Implicit        Path
	Implicits       Paths
	OrderOnly       Paths
	Default         bool
	Args            map[string]string
}

type ModuleBuildParams BuildParams

type androidBaseContext interface {
	Target() Target
	TargetPrimary() bool
	Arch() Arch
	Os() OsType
	Host() bool
	Device() bool
	Darwin() bool
	Windows() bool
	Debug() bool
	PrimaryArch() bool
	InstallOnVendorPartition() bool
	AConfig() Config
	DeviceConfig() DeviceConfig
}

type BaseContext interface {
	blueprint.BaseModuleContext
	androidBaseContext
}

type ModuleContext interface {
	androidBaseContext
	blueprint.BaseModuleContext

	// Deprecated: use ModuleContext.Build instead.
	ModuleBuild(pctx blueprint.PackageContext, params ModuleBuildParams)

	ExpandSources(srcFiles, excludes []string) Paths
	ExpandSourcesSubDir(srcFiles, excludes []string, subDir string) Paths
	Glob(globPattern string, excludes []string) Paths

	InstallExecutable(installPath OutputPath, name string, srcPath Path, deps ...Path) OutputPath
	InstallFile(installPath OutputPath, name string, srcPath Path, deps ...Path) OutputPath
	InstallSymlink(installPath OutputPath, name string, srcPath OutputPath) OutputPath
	CheckbuildFile(srcPath Path)

	AddMissingDependencies(deps []string)

	InstallInData() bool
	InstallInSanitizerDir() bool

	RequiredModuleNames() []string

	// android.ModuleContext methods
	// These are duplicated instead of embedded so that can eventually be wrapped to take an
	// android.Module instead of a blueprint.Module
	OtherModuleName(m blueprint.Module) string
	OtherModuleErrorf(m blueprint.Module, fmt string, args ...interface{})
	OtherModuleDependencyTag(m blueprint.Module) blueprint.DependencyTag

	GetDirectDepWithTag(name string, tag blueprint.DependencyTag) blueprint.Module
	GetDirectDep(name string) (blueprint.Module, blueprint.DependencyTag)

	ModuleSubDir() string

	VisitDirectDeps(visit func(Module))
	VisitDirectDepsIf(pred func(Module) bool, visit func(Module))
	VisitDepsDepthFirst(visit func(Module))
	VisitDepsDepthFirstIf(pred func(Module) bool, visit func(Module))
	WalkDeps(visit func(Module, Module) bool)

	Variable(pctx blueprint.PackageContext, name, value string)
	Rule(pctx blueprint.PackageContext, name string, params blueprint.RuleParams, argNames ...string) blueprint.Rule
	// Similar to blueprint.ModuleContext.Build, but takes Paths instead of []string,
	// and performs more verification.
	Build(pctx blueprint.PackageContext, params BuildParams)

	PrimaryModule() blueprint.Module
	FinalModule() blueprint.Module
	VisitAllModuleVariants(visit func(blueprint.Module))

	GetMissingDependencies() []string
}

type Module interface {
	blueprint.Module

	// GenerateAndroidBuildActions is analogous to Blueprints' GenerateBuildActions,
	// but GenerateAndroidBuildActions also has access to Android-specific information.
	// For more information, see Module.GenerateBuildActions within Blueprint's module_ctx.go
	GenerateAndroidBuildActions(ModuleContext)

	DepsMutator(BottomUpMutatorContext)

	base() *ModuleBase
	Enabled() bool
	Target() Target
	InstallInData() bool
	InstallInSanitizerDir() bool
	SkipInstall()

	AddProperties(props ...interface{})
	GetProperties() []interface{}

	BuildParamsForTests() []BuildParams
}

type nameProperties struct {
	// The name of the module.  Must be unique across all modules.
	Name *string
}

type commonProperties struct {
	Tags []string

	// emit build rules for this module
	Enabled *bool `android:"arch_variant"`

	// control whether this module compiles for 32-bit, 64-bit, or both.  Possible values
	// are "32" (compile for 32-bit only), "64" (compile for 64-bit only), "both" (compile for both
	// architectures), or "first" (compile for 64-bit on a 64-bit platform, and 32-bit on a 32-bit
	// platform
	Compile_multilib *string `android:"arch_variant"`

	Target struct {
		Host struct {
			Compile_multilib *string
		}
		Android struct {
			Compile_multilib *string
		}
	}

	Default_multilib string `blueprint:"mutated"`

	// whether this is a proprietary vendor module, and should be installed into /vendor
	Proprietary *bool

	// vendor who owns this module
	Owner *string

	// whether this module is device specific and should be installed into /vendor
	Vendor *bool

	// *.logtags files, to combine together in order to generate the /system/etc/event-log-tags
	// file
	Logtags []string

	// init.rc files to be installed if this module is installed
	Init_rc []string

	// names of other modules to install if this module is installed
	Required []string `android:"arch_variant"`

	// relative path to a file to include in the list of notices for the device
	Notice *string

	// Set by TargetMutator
	CompileTarget  Target `blueprint:"mutated"`
	CompilePrimary bool   `blueprint:"mutated"`

	// Set by InitAndroidModule
	HostOrDeviceSupported HostOrDeviceSupported `blueprint:"mutated"`
	ArchSpecific          bool                  `blueprint:"mutated"`

	SkipInstall bool `blueprint:"mutated"`
}

type hostAndDeviceProperties struct {
	Host_supported   *bool
	Device_supported *bool
}

type Multilib string

const (
	MultilibBoth    Multilib = "both"
	MultilibFirst   Multilib = "first"
	MultilibCommon  Multilib = "common"
	MultilibDefault Multilib = ""
)

type HostOrDeviceSupported int

const (
	_ HostOrDeviceSupported = iota
	HostSupported
	HostSupportedNoCross
	DeviceSupported
	HostAndDeviceSupported
	HostAndDeviceDefault
	NeitherHostNorDeviceSupported
)

func InitAndroidModule(m Module) {
	base := m.base()
	base.module = m

	m.AddProperties(
		&base.nameProperties,
		&base.commonProperties,
		&base.variableProperties)
}

func InitAndroidArchModule(m Module, hod HostOrDeviceSupported, defaultMultilib Multilib) {
	InitAndroidModule(m)

	base := m.base()
	base.commonProperties.HostOrDeviceSupported = hod
	base.commonProperties.Default_multilib = string(defaultMultilib)
	base.commonProperties.ArchSpecific = true

	switch hod {
	case HostAndDeviceSupported, HostAndDeviceDefault:
		m.AddProperties(&base.hostAndDeviceProperties)
	}

	InitArchModule(m)
}

// A ModuleBase object contains the properties that are common to all Android
// modules.  It should be included as an anonymous field in every module
// struct definition.  InitAndroidModule should then be called from the module's
// factory function, and the return values from InitAndroidModule should be
// returned from the factory function.
//
// The ModuleBase type is responsible for implementing the GenerateBuildActions
// method to support the blueprint.Module interface. This method will then call
// the module's GenerateAndroidBuildActions method once for each build variant
// that is to be built. GenerateAndroidBuildActions is passed a
// AndroidModuleContext rather than the usual blueprint.ModuleContext.
// AndroidModuleContext exposes extra functionality specific to the Android build
// system including details about the particular build variant that is to be
// generated.
//
// For example:
//
//     import (
//         "android/soong/android"
//     )
//
//     type myModule struct {
//         android.ModuleBase
//         properties struct {
//             MyProperty string
//         }
//     }
//
//     func NewMyModule() android.Module) {
//         m := &myModule{}
//         m.AddProperties(&m.properties)
//         android.InitAndroidModule(m)
//         return m
//     }
//
//     func (m *myModule) GenerateAndroidBuildActions(ctx android.ModuleContext) {
//         // Get the CPU architecture for the current build variant.
//         variantArch := ctx.Arch()
//
//         // ...
//     }
type ModuleBase struct {
	// Putting the curiously recurring thing pointing to the thing that contains
	// the thing pattern to good use.
	// TODO: remove this
	module Module

	nameProperties          nameProperties
	commonProperties        commonProperties
	variableProperties      variableProperties
	hostAndDeviceProperties hostAndDeviceProperties
	generalProperties       []interface{}
	archProperties          []interface{}
	customizableProperties  []interface{}

	noAddressSanitizer bool
	installFiles       Paths
	checkbuildFiles    Paths

	// Used by buildTargetSingleton to create checkbuild and per-directory build targets
	// Only set on the final variant of each module
	installTarget    string
	checkbuildTarget string
	blueprintDir     string

	hooks hooks

	registerProps []interface{}

	// For tests
	buildParams []BuildParams
}

func (a *ModuleBase) AddProperties(props ...interface{}) {
	a.registerProps = append(a.registerProps, props...)
}

func (a *ModuleBase) GetProperties() []interface{} {
	return a.registerProps
}

func (a *ModuleBase) BuildParamsForTests() []BuildParams {
	return a.buildParams
}

// Name returns the name of the module.  It may be overridden by individual module types, for
// example prebuilts will prepend prebuilt_ to the name.
func (a *ModuleBase) Name() string {
	return String(a.nameProperties.Name)
}

// BaseModuleName returns the name of the module as specified in the blueprints file.
func (a *ModuleBase) BaseModuleName() string {
	return String(a.nameProperties.Name)
}

func (a *ModuleBase) base() *ModuleBase {
	return a
}

func (a *ModuleBase) SetTarget(target Target, primary bool) {
	a.commonProperties.CompileTarget = target
	a.commonProperties.CompilePrimary = primary
}

func (a *ModuleBase) Target() Target {
	return a.commonProperties.CompileTarget
}

func (a *ModuleBase) TargetPrimary() bool {
	return a.commonProperties.CompilePrimary
}

func (a *ModuleBase) Os() OsType {
	return a.Target().Os
}

func (a *ModuleBase) Host() bool {
	return a.Os().Class == Host || a.Os().Class == HostCross
}

func (a *ModuleBase) Arch() Arch {
	return a.Target().Arch
}

func (a *ModuleBase) ArchSpecific() bool {
	return a.commonProperties.ArchSpecific
}

func (a *ModuleBase) OsClassSupported() []OsClass {
	switch a.commonProperties.HostOrDeviceSupported {
	case HostSupported:
		return []OsClass{Host, HostCross}
	case HostSupportedNoCross:
		return []OsClass{Host}
	case DeviceSupported:
		return []OsClass{Device}
	case HostAndDeviceSupported:
		var supported []OsClass
		if Bool(a.hostAndDeviceProperties.Host_supported) {
			supported = append(supported, Host, HostCross)
		}
		if a.hostAndDeviceProperties.Device_supported == nil ||
			*a.hostAndDeviceProperties.Device_supported {
			supported = append(supported, Device)
		}
		return supported
	default:
		return nil
	}
}

func (a *ModuleBase) DeviceSupported() bool {
	return a.commonProperties.HostOrDeviceSupported == DeviceSupported ||
		a.commonProperties.HostOrDeviceSupported == HostAndDeviceSupported &&
			(a.hostAndDeviceProperties.Device_supported == nil ||
				*a.hostAndDeviceProperties.Device_supported)
}

func (a *ModuleBase) Enabled() bool {
	if a.commonProperties.Enabled == nil {
		return !a.Os().DefaultDisabled
	}
	return *a.commonProperties.Enabled
}

func (a *ModuleBase) SkipInstall() {
	a.commonProperties.SkipInstall = true
}

func (a *ModuleBase) computeInstallDeps(
	ctx blueprint.ModuleContext) Paths {

	result := Paths{}
	ctx.VisitDepsDepthFirstIf(isFileInstaller,
		func(m blueprint.Module) {
			fileInstaller := m.(fileInstaller)
			files := fileInstaller.filesToInstall()
			result = append(result, files...)
		})

	return result
}

func (a *ModuleBase) filesToInstall() Paths {
	return a.installFiles
}

func (p *ModuleBase) NoAddressSanitizer() bool {
	return p.noAddressSanitizer
}

func (p *ModuleBase) InstallInData() bool {
	return false
}

func (p *ModuleBase) InstallInSanitizerDir() bool {
	return false
}

func (a *ModuleBase) generateModuleTarget(ctx blueprint.ModuleContext) {
	allInstalledFiles := Paths{}
	allCheckbuildFiles := Paths{}
	ctx.VisitAllModuleVariants(func(module blueprint.Module) {
		a := module.(Module).base()
		allInstalledFiles = append(allInstalledFiles, a.installFiles...)
		allCheckbuildFiles = append(allCheckbuildFiles, a.checkbuildFiles...)
	})

	deps := []string{}

	if len(allInstalledFiles) > 0 {
		name := ctx.ModuleName() + "-install"
		ctx.Build(pctx, blueprint.BuildParams{
			Rule:      blueprint.Phony,
			Outputs:   []string{name},
			Implicits: allInstalledFiles.Strings(),
			Optional:  ctx.Config().(Config).EmbeddedInMake(),
		})
		deps = append(deps, name)
		a.installTarget = name
	}

	if len(allCheckbuildFiles) > 0 {
		name := ctx.ModuleName() + "-checkbuild"
		ctx.Build(pctx, blueprint.BuildParams{
			Rule:      blueprint.Phony,
			Outputs:   []string{name},
			Implicits: allCheckbuildFiles.Strings(),
			Optional:  true,
		})
		deps = append(deps, name)
		a.checkbuildTarget = name
	}

	if len(deps) > 0 {
		suffix := ""
		if ctx.Config().(Config).EmbeddedInMake() {
			suffix = "-soong"
		}

		ctx.Build(pctx, blueprint.BuildParams{
			Rule:      blueprint.Phony,
			Outputs:   []string{ctx.ModuleName() + suffix},
			Implicits: deps,
			Optional:  true,
		})

		a.blueprintDir = ctx.ModuleDir()
	}
}

func (a *ModuleBase) androidBaseContextFactory(ctx blueprint.BaseModuleContext) androidBaseContextImpl {
	return androidBaseContextImpl{
		target:        a.commonProperties.CompileTarget,
		targetPrimary: a.commonProperties.CompilePrimary,
		vendor:        Bool(a.commonProperties.Proprietary) || Bool(a.commonProperties.Vendor),
		config:        ctx.Config().(Config),
	}
}

func (a *ModuleBase) GenerateBuildActions(ctx blueprint.ModuleContext) {
	androidCtx := &androidModuleContext{
		module:                 a.module,
		ModuleContext:          ctx,
		androidBaseContextImpl: a.androidBaseContextFactory(ctx),
		installDeps:            a.computeInstallDeps(ctx),
		installFiles:           a.installFiles,
		missingDeps:            ctx.GetMissingDependencies(),
	}

	desc := "//" + ctx.ModuleDir() + ":" + ctx.ModuleName() + " "
	var suffix []string
	if androidCtx.Os().Class != Device && androidCtx.Os().Class != Generic {
		suffix = append(suffix, androidCtx.Os().String())
	}
	if !androidCtx.PrimaryArch() {
		suffix = append(suffix, androidCtx.Arch().ArchType.String())
	}

	ctx.Variable(pctx, "moduleDesc", desc)

	s := ""
	if len(suffix) > 0 {
		s = " [" + strings.Join(suffix, " ") + "]"
	}
	ctx.Variable(pctx, "moduleDescSuffix", s)

	if a.Enabled() {
		a.module.GenerateAndroidBuildActions(androidCtx)
		if ctx.Failed() {
			return
		}

		a.installFiles = append(a.installFiles, androidCtx.installFiles...)
		a.checkbuildFiles = append(a.checkbuildFiles, androidCtx.checkbuildFiles...)
	}

	if a == ctx.FinalModule().(Module).base() {
		a.generateModuleTarget(ctx)
		if ctx.Failed() {
			return
		}
	}

	a.buildParams = androidCtx.buildParams
}

type androidBaseContextImpl struct {
	target        Target
	targetPrimary bool
	debug         bool
	vendor        bool
	config        Config
}

type androidModuleContext struct {
	blueprint.ModuleContext
	androidBaseContextImpl
	installDeps     Paths
	installFiles    Paths
	checkbuildFiles Paths
	missingDeps     []string
	module          Module

	// For tests
	buildParams []BuildParams
}

func (a *androidModuleContext) ninjaError(desc string, outputs []string, err error) {
	a.ModuleContext.Build(pctx, blueprint.BuildParams{
		Rule:        ErrorRule,
		Description: desc,
		Outputs:     outputs,
		Optional:    true,
		Args: map[string]string{
			"error": err.Error(),
		},
	})
	return
}

func (a *androidModuleContext) ModuleBuild(pctx blueprint.PackageContext, params ModuleBuildParams) {
	a.Build(pctx, BuildParams(params))
}

func (a *androidModuleContext) Build(pctx blueprint.PackageContext, params BuildParams) {
	if a.config.captureBuild {
		a.buildParams = append(a.buildParams, params)
	}

	bparams := blueprint.BuildParams{
		Rule:            params.Rule,
		Deps:            params.Deps,
		Outputs:         params.Outputs.Strings(),
		ImplicitOutputs: params.ImplicitOutputs.Strings(),
		Inputs:          params.Inputs.Strings(),
		Implicits:       params.Implicits.Strings(),
		OrderOnly:       params.OrderOnly.Strings(),
		Args:            params.Args,
		Optional:        !params.Default,
	}

	if params.Description != "" {
		bparams.Description = "${moduleDesc}" + params.Description + "${moduleDescSuffix}"
	}

	if params.Depfile != nil {
		bparams.Depfile = params.Depfile.String()
	}
	if params.Output != nil {
		bparams.Outputs = append(bparams.Outputs, params.Output.String())
	}
	if params.ImplicitOutput != nil {
		bparams.ImplicitOutputs = append(bparams.ImplicitOutputs, params.ImplicitOutput.String())
	}
	if params.Input != nil {
		bparams.Inputs = append(bparams.Inputs, params.Input.String())
	}
	if params.Implicit != nil {
		bparams.Implicits = append(bparams.Implicits, params.Implicit.String())
	}

	if a.missingDeps != nil {
		a.ninjaError(bparams.Description, bparams.Outputs,
			fmt.Errorf("module %s missing dependencies: %s\n",
				a.ModuleName(), strings.Join(a.missingDeps, ", ")))
		return
	}

	a.ModuleContext.Build(pctx, bparams)
}

func (a *androidModuleContext) GetMissingDependencies() []string {
	return a.missingDeps
}

func (a *androidModuleContext) AddMissingDependencies(deps []string) {
	if deps != nil {
		a.missingDeps = append(a.missingDeps, deps...)
		a.missingDeps = FirstUniqueStrings(a.missingDeps)
	}
}

func (a *androidModuleContext) validateAndroidModule(module blueprint.Module) Module {
	aModule, _ := module.(Module)
	if aModule == nil {
		a.ModuleErrorf("module %q not an android module", a.OtherModuleName(aModule))
		return nil
	}

	if !aModule.Enabled() {
		if a.AConfig().AllowMissingDependencies() {
			a.AddMissingDependencies([]string{a.OtherModuleName(aModule)})
		} else {
			a.ModuleErrorf("depends on disabled module %q", a.OtherModuleName(aModule))
		}
		return nil
	}

	return aModule
}

func (a *androidModuleContext) VisitDirectDeps(visit func(Module)) {
	a.ModuleContext.VisitDirectDeps(func(module blueprint.Module) {
		if aModule := a.validateAndroidModule(module); aModule != nil {
			visit(aModule)
		}
	})
}

func (a *androidModuleContext) VisitDirectDepsIf(pred func(Module) bool, visit func(Module)) {
	a.ModuleContext.VisitDirectDepsIf(
		// pred
		func(module blueprint.Module) bool {
			if aModule := a.validateAndroidModule(module); aModule != nil {
				return pred(aModule)
			} else {
				return false
			}
		},
		// visit
		func(module blueprint.Module) {
			visit(module.(Module))
		})
}

func (a *androidModuleContext) VisitDepsDepthFirst(visit func(Module)) {
	a.ModuleContext.VisitDepsDepthFirst(func(module blueprint.Module) {
		if aModule := a.validateAndroidModule(module); aModule != nil {
			visit(aModule)
		}
	})
}

func (a *androidModuleContext) VisitDepsDepthFirstIf(pred func(Module) bool, visit func(Module)) {
	a.ModuleContext.VisitDepsDepthFirstIf(
		// pred
		func(module blueprint.Module) bool {
			if aModule := a.validateAndroidModule(module); aModule != nil {
				return pred(aModule)
			} else {
				return false
			}
		},
		// visit
		func(module blueprint.Module) {
			visit(module.(Module))
		})
}

func (a *androidModuleContext) WalkDeps(visit func(Module, Module) bool) {
	a.ModuleContext.WalkDeps(func(child, parent blueprint.Module) bool {
		childAndroidModule := a.validateAndroidModule(child)
		parentAndroidModule := a.validateAndroidModule(parent)
		if childAndroidModule != nil && parentAndroidModule != nil {
			return visit(childAndroidModule, parentAndroidModule)
		} else {
			return false
		}
	})
}

func (a *androidBaseContextImpl) Target() Target {
	return a.target
}

func (a *androidBaseContextImpl) TargetPrimary() bool {
	return a.targetPrimary
}

func (a *androidBaseContextImpl) Arch() Arch {
	return a.target.Arch
}

func (a *androidBaseContextImpl) Os() OsType {
	return a.target.Os
}

func (a *androidBaseContextImpl) Host() bool {
	return a.target.Os.Class == Host || a.target.Os.Class == HostCross
}

func (a *androidBaseContextImpl) Device() bool {
	return a.target.Os.Class == Device
}

func (a *androidBaseContextImpl) Darwin() bool {
	return a.target.Os == Darwin
}

func (a *androidBaseContextImpl) Windows() bool {
	return a.target.Os == Windows
}

func (a *androidBaseContextImpl) Debug() bool {
	return a.debug
}

func (a *androidBaseContextImpl) PrimaryArch() bool {
	if len(a.config.Targets[a.target.Os.Class]) <= 1 {
		return true
	}
	return a.target.Arch.ArchType == a.config.Targets[a.target.Os.Class][0].Arch.ArchType
}

func (a *androidBaseContextImpl) AConfig() Config {
	return a.config
}

func (a *androidBaseContextImpl) DeviceConfig() DeviceConfig {
	return DeviceConfig{a.config.deviceConfig}
}

func (a *androidBaseContextImpl) InstallOnVendorPartition() bool {
	return a.vendor
}

func (a *androidModuleContext) InstallInData() bool {
	return a.module.InstallInData()
}

func (a *androidModuleContext) InstallInSanitizerDir() bool {
	return a.module.InstallInSanitizerDir()
}

func (a *androidModuleContext) skipInstall(fullInstallPath OutputPath) bool {
	if a.module.base().commonProperties.SkipInstall {
		return true
	}

	if a.Device() {
		if a.AConfig().SkipDeviceInstall() {
			return true
		}

		if a.AConfig().SkipMegaDeviceInstall(fullInstallPath.String()) {
			return true
		}
	}

	return false
}

func (a *androidModuleContext) InstallFile(installPath OutputPath, name string, srcPath Path,
	deps ...Path) OutputPath {
	return a.installFile(installPath, name, srcPath, Cp, deps)
}

func (a *androidModuleContext) InstallExecutable(installPath OutputPath, name string, srcPath Path,
	deps ...Path) OutputPath {
	return a.installFile(installPath, name, srcPath, CpExecutable, deps)
}

func (a *androidModuleContext) installFile(installPath OutputPath, name string, srcPath Path,
	rule blueprint.Rule, deps []Path) OutputPath {

	fullInstallPath := installPath.Join(a, name)
	a.module.base().hooks.runInstallHooks(a, fullInstallPath, false)

	if !a.skipInstall(fullInstallPath) {

		deps = append(deps, a.installDeps...)

		var implicitDeps, orderOnlyDeps Paths

		if a.Host() {
			// Installed host modules might be used during the build, depend directly on their
			// dependencies so their timestamp is updated whenever their dependency is updated
			implicitDeps = deps
		} else {
			orderOnlyDeps = deps
		}

		a.Build(pctx, BuildParams{
			Rule:        rule,
			Description: "install " + fullInstallPath.Base(),
			Output:      fullInstallPath,
			Input:       srcPath,
			Implicits:   implicitDeps,
			OrderOnly:   orderOnlyDeps,
			Default:     !a.AConfig().EmbeddedInMake(),
		})

		a.installFiles = append(a.installFiles, fullInstallPath)
	}
	a.checkbuildFiles = append(a.checkbuildFiles, srcPath)
	return fullInstallPath
}

func (a *androidModuleContext) InstallSymlink(installPath OutputPath, name string, srcPath OutputPath) OutputPath {
	fullInstallPath := installPath.Join(a, name)
	a.module.base().hooks.runInstallHooks(a, fullInstallPath, true)

	if !a.skipInstall(fullInstallPath) {

		a.Build(pctx, BuildParams{
			Rule:        Symlink,
			Description: "install symlink " + fullInstallPath.Base(),
			Output:      fullInstallPath,
			OrderOnly:   Paths{srcPath},
			Default:     !a.AConfig().EmbeddedInMake(),
			Args: map[string]string{
				"fromPath": srcPath.String(),
			},
		})

		a.installFiles = append(a.installFiles, fullInstallPath)
		a.checkbuildFiles = append(a.checkbuildFiles, srcPath)
	}
	return fullInstallPath
}

func (a *androidModuleContext) CheckbuildFile(srcPath Path) {
	a.checkbuildFiles = append(a.checkbuildFiles, srcPath)
}

type fileInstaller interface {
	filesToInstall() Paths
}

func isFileInstaller(m blueprint.Module) bool {
	_, ok := m.(fileInstaller)
	return ok
}

func isAndroidModule(m blueprint.Module) bool {
	_, ok := m.(Module)
	return ok
}

func findStringInSlice(str string, slice []string) int {
	for i, s := range slice {
		if s == str {
			return i
		}
	}
	return -1
}

func SrcIsModule(s string) string {
	if len(s) > 1 && s[0] == ':' {
		return s[1:]
	}
	return ""
}

type sourceDependencyTag struct {
	blueprint.BaseDependencyTag
}

var SourceDepTag sourceDependencyTag

// Returns a list of modules that must be depended on to satisfy filegroup or generated sources
// modules listed in srcFiles using ":module" syntax
func ExtractSourcesDeps(ctx BottomUpMutatorContext, srcFiles []string) {
	var deps []string
	set := make(map[string]bool)

	for _, s := range srcFiles {
		if m := SrcIsModule(s); m != "" {
			if _, found := set[m]; found {
				ctx.ModuleErrorf("found source dependency duplicate: %q!", m)
			} else {
				set[m] = true
				deps = append(deps, m)
			}
		}
	}

	ctx.AddDependency(ctx.Module(), SourceDepTag, deps...)
}

type SourceFileProducer interface {
	Srcs() Paths
}

// Returns a list of paths expanded from globs and modules referenced using ":module" syntax.
// ExtractSourcesDeps must have already been called during the dependency resolution phase.
func (ctx *androidModuleContext) ExpandSources(srcFiles, excludes []string) Paths {
	return ctx.ExpandSourcesSubDir(srcFiles, excludes, "")
}

func (ctx *androidModuleContext) ExpandSourcesSubDir(srcFiles, excludes []string, subDir string) Paths {
	prefix := PathForModuleSrc(ctx).String()

	for i, e := range excludes {
		j := findStringInSlice(e, srcFiles)
		if j != -1 {
			srcFiles = append(srcFiles[:j], srcFiles[j+1:]...)
		}

		excludes[i] = filepath.Join(prefix, e)
	}

	expandedSrcFiles := make(Paths, 0, len(srcFiles))
	for _, s := range srcFiles {
		if m := SrcIsModule(s); m != "" {
			module := ctx.GetDirectDepWithTag(m, SourceDepTag)
			if module == nil {
				// Error will have been handled by ExtractSourcesDeps
				continue
			}
			if srcProducer, ok := module.(SourceFileProducer); ok {
				expandedSrcFiles = append(expandedSrcFiles, srcProducer.Srcs()...)
			} else {
				ctx.ModuleErrorf("srcs dependency %q is not a source file producing module", m)
			}
		} else if pathtools.IsGlob(s) {
			globbedSrcFiles := ctx.Glob(filepath.Join(prefix, s), excludes)
			for i, s := range globbedSrcFiles {
				globbedSrcFiles[i] = s.(ModuleSrcPath).WithSubDir(ctx, subDir)
			}
			expandedSrcFiles = append(expandedSrcFiles, globbedSrcFiles...)
		} else {
			s := PathForModuleSrc(ctx, s).WithSubDir(ctx, subDir)
			expandedSrcFiles = append(expandedSrcFiles, s)
		}
	}

	return expandedSrcFiles
}

func (ctx *androidModuleContext) RequiredModuleNames() []string {
	return ctx.module.base().commonProperties.Required
}

func (ctx *androidModuleContext) Glob(globPattern string, excludes []string) Paths {
	ret, err := ctx.GlobWithDeps(globPattern, excludes)
	if err != nil {
		ctx.ModuleErrorf("glob: %s", err.Error())
	}
	return pathsForModuleSrcFromFullPath(ctx, ret)
}

func init() {
	RegisterSingletonType("buildtarget", BuildTargetSingleton)
}

func BuildTargetSingleton() blueprint.Singleton {
	return &buildTargetSingleton{}
}

func parentDir(dir string) string {
	dir, _ = filepath.Split(dir)
	return filepath.Clean(dir)
}

type buildTargetSingleton struct{}

func (c *buildTargetSingleton) GenerateBuildActions(ctx blueprint.SingletonContext) {
	checkbuildDeps := []string{}

	mmTarget := func(dir string) string {
		return "MODULES-IN-" + strings.Replace(filepath.Clean(dir), "/", "-", -1)
	}

	modulesInDir := make(map[string][]string)

	ctx.VisitAllModules(func(module blueprint.Module) {
		if a, ok := module.(Module); ok {
			blueprintDir := a.base().blueprintDir
			installTarget := a.base().installTarget
			checkbuildTarget := a.base().checkbuildTarget

			if checkbuildTarget != "" {
				checkbuildDeps = append(checkbuildDeps, checkbuildTarget)
				modulesInDir[blueprintDir] = append(modulesInDir[blueprintDir], checkbuildTarget)
			}

			if installTarget != "" {
				modulesInDir[blueprintDir] = append(modulesInDir[blueprintDir], installTarget)
			}
		}
	})

	suffix := ""
	if ctx.Config().(Config).EmbeddedInMake() {
		suffix = "-soong"
	}

	// Create a top-level checkbuild target that depends on all modules
	ctx.Build(pctx, blueprint.BuildParams{
		Rule:      blueprint.Phony,
		Outputs:   []string{"checkbuild" + suffix},
		Implicits: checkbuildDeps,
		Optional:  true,
	})

	// Make will generate the MODULES-IN-* targets
	if ctx.Config().(Config).EmbeddedInMake() {
		return
	}

	// Ensure ancestor directories are in modulesInDir
	dirs := sortedKeys(modulesInDir)
	for _, dir := range dirs {
		dir := parentDir(dir)
		for dir != "." && dir != "/" {
			if _, exists := modulesInDir[dir]; exists {
				break
			}
			modulesInDir[dir] = nil
			dir = parentDir(dir)
		}
	}

	// Make directories build their direct subdirectories
	dirs = sortedKeys(modulesInDir)
	for _, dir := range dirs {
		p := parentDir(dir)
		if p != "." && p != "/" {
			modulesInDir[p] = append(modulesInDir[p], mmTarget(dir))
		}
	}

	// Create a MODULES-IN-<directory> target that depends on all modules in a directory, and
	// depends on the MODULES-IN-* targets of all of its subdirectories that contain Android.bp
	// files.
	for _, dir := range dirs {
		ctx.Build(pctx, blueprint.BuildParams{
			Rule:      blueprint.Phony,
			Outputs:   []string{mmTarget(dir)},
			Implicits: modulesInDir[dir],
			// HACK: checkbuild should be an optional build, but force it
			// enabled for now in standalone builds
			Optional: ctx.Config().(Config).EmbeddedInMake(),
		})
	}

	// Create (host|host-cross|target)-<OS> phony rules to build a reduced checkbuild.
	osDeps := map[OsType]Paths{}
	ctx.VisitAllModules(func(module blueprint.Module) {
		if a, ok := module.(Module); ok {
			if a.Enabled() {
				os := a.Target().Os
				osDeps[os] = append(osDeps[os], a.base().checkbuildFiles...)
			}
		}
	})

	osClass := make(map[string][]string)
	for os, deps := range osDeps {
		var className string

		switch os.Class {
		case Host:
			className = "host"
		case HostCross:
			className = "host-cross"
		case Device:
			className = "target"
		default:
			continue
		}

		name := className + "-" + os.Name
		osClass[className] = append(osClass[className], name)

		ctx.Build(pctx, blueprint.BuildParams{
			Rule:      blueprint.Phony,
			Outputs:   []string{name},
			Implicits: deps.Strings(),
			Optional:  true,
		})
	}

	// Wrap those into host|host-cross|target phony rules
	osClasses := sortedKeys(osClass)
	for _, class := range osClasses {
		ctx.Build(pctx, blueprint.BuildParams{
			Rule:      blueprint.Phony,
			Outputs:   []string{class},
			Implicits: osClass[class],
			Optional:  true,
		})
	}
}

type AndroidModulesByName struct {
	slice []Module
	ctx   interface {
		ModuleName(blueprint.Module) string
		ModuleSubDir(blueprint.Module) string
	}
}

func (s AndroidModulesByName) Len() int { return len(s.slice) }
func (s AndroidModulesByName) Less(i, j int) bool {
	mi, mj := s.slice[i], s.slice[j]
	ni, nj := s.ctx.ModuleName(mi), s.ctx.ModuleName(mj)

	if ni != nj {
		return ni < nj
	} else {
		return s.ctx.ModuleSubDir(mi) < s.ctx.ModuleSubDir(mj)
	}
}
func (s AndroidModulesByName) Swap(i, j int) { s.slice[i], s.slice[j] = s.slice[j], s.slice[i] }