java/hiddenapi_modular.go - platform/build/soong - Git at Google

 // Copyright (C) 2021 The Android Open Source Project
 //
 // 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 (
 	"android/soong/android"
 	"github.com/google/blueprint"
 )

 // Contains support for processing hiddenAPI in a modular fashion.

 type hiddenAPIStubsDependencyTag struct {
 	blueprint.BaseDependencyTag
 	sdkKind android.SdkKind
 }

 func (b hiddenAPIStubsDependencyTag) ExcludeFromApexContents() {
 }

 func (b hiddenAPIStubsDependencyTag) ReplaceSourceWithPrebuilt() bool {
 	return false
 }

 // Avoid having to make stubs content explicitly visible to dependent modules.
 //
 // This is a temporary workaround to make it easier to migrate to bootclasspath_fragment modules
 // with proper dependencies.
 // TODO(b/177892522): Remove this and add needed visibility.
 func (b hiddenAPIStubsDependencyTag) ExcludeFromVisibilityEnforcement() {
 }

 var _ android.ExcludeFromVisibilityEnforcementTag = hiddenAPIStubsDependencyTag{}
 var _ android.ReplaceSourceWithPrebuilt = hiddenAPIStubsDependencyTag{}
 var _ android.ExcludeFromApexContentsTag = hiddenAPIStubsDependencyTag{}

 // hiddenAPIRelevantSdkKinds lists all the android.SdkKind instances that are needed by the hidden
 // API processing.
 var hiddenAPIRelevantSdkKinds = []android.SdkKind{
 	android.SdkPublic,
 	android.SdkSystem,
 	android.SdkTest,
 	android.SdkCorePlatform,
 }

 // hiddenAPIComputeMonolithicStubLibModules computes the set of module names that provide stubs
 // needed to produce the hidden API monolithic stub flags file.
 func hiddenAPIComputeMonolithicStubLibModules(config android.Config) map[android.SdkKind][]string {
 	var publicStubModules []string
 	var systemStubModules []string
 	var testStubModules []string
 	var corePlatformStubModules []string

 	if config.AlwaysUsePrebuiltSdks() {
 		// Build configuration mandates using prebuilt stub modules
 		publicStubModules = append(publicStubModules, "sdk_public_current_android")
 		systemStubModules = append(systemStubModules, "sdk_system_current_android")
 		testStubModules = append(testStubModules, "sdk_test_current_android")
 	} else {
 		// Use stub modules built from source
 		publicStubModules = append(publicStubModules, "android_stubs_current")
 		systemStubModules = append(systemStubModules, "android_system_stubs_current")
 		testStubModules = append(testStubModules, "android_test_stubs_current")
 	}
 	// We do not have prebuilts of the core platform api yet
 	corePlatformStubModules = append(corePlatformStubModules, "legacy.core.platform.api.stubs")

 	// Allow products to define their own stubs for custom product jars that apps can use.
 	publicStubModules = append(publicStubModules, config.ProductHiddenAPIStubs()...)
 	systemStubModules = append(systemStubModules, config.ProductHiddenAPIStubsSystem()...)
 	testStubModules = append(testStubModules, config.ProductHiddenAPIStubsTest()...)
 	if config.IsEnvTrue("EMMA_INSTRUMENT") {
 		publicStubModules = append(publicStubModules, "jacoco-stubs")
 	}

 	m := map[android.SdkKind][]string{}
 	m[android.SdkPublic] = publicStubModules
 	m[android.SdkSystem] = systemStubModules
 	m[android.SdkTest] = testStubModules
 	m[android.SdkCorePlatform] = corePlatformStubModules
 	return m
 }

 // hiddenAPIAddStubLibDependencies adds dependencies onto the modules specified in
 // sdkKindToStubLibModules. It adds them in a well known order and uses an SdkKind specific tag to
 // identify the source of the dependency.
 func hiddenAPIAddStubLibDependencies(ctx android.BottomUpMutatorContext, sdkKindToStubLibModules map[android.SdkKind][]string) {
 	module := ctx.Module()
 	for _, sdkKind := range hiddenAPIRelevantSdkKinds {
 		modules := sdkKindToStubLibModules[sdkKind]
 		ctx.AddDependency(module, hiddenAPIStubsDependencyTag{sdkKind: sdkKind}, modules...)
 	}
 }

 // hiddenAPIGatherStubLibDexJarPaths gathers the paths to the dex jars from the dependencies added
 // in hiddenAPIAddStubLibDependencies.
 func hiddenAPIGatherStubLibDexJarPaths(ctx android.ModuleContext) map[android.SdkKind]android.Paths {
 	m := map[android.SdkKind]android.Paths{}
 	ctx.VisitDirectDepsIf(isActiveModule, func(module android.Module) {
 		tag := ctx.OtherModuleDependencyTag(module)
 		if hiddenAPIStubsTag, ok := tag.(hiddenAPIStubsDependencyTag); ok {
 			kind := hiddenAPIStubsTag.sdkKind
 			dexJar := hiddenAPIRetrieveDexJarBuildPath(ctx, module)
 			if dexJar != nil {
 				m[kind] = append(m[kind], dexJar)
 			}
 		}
 	})
 	return m
 }

 // hiddenAPIRetrieveDexJarBuildPath retrieves the DexJarBuildPath from the specified module, if
 // available, or reports an error.
 func hiddenAPIRetrieveDexJarBuildPath(ctx android.ModuleContext, module android.Module) android.Path {
 	if j, ok := module.(UsesLibraryDependency); ok {
 		dexJar := j.DexJarBuildPath()
 		if dexJar != nil {
 			return dexJar
 		}
 		ctx.ModuleErrorf("dependency %s does not provide a dex jar, consider setting compile_dex: true", module)
 	} else {
 		ctx.ModuleErrorf("dependency %s of module type %s does not support providing a dex jar", module, ctx.OtherModuleType(module))
 	}
 	return nil
 }

 var sdkKindToHiddenapiListOption = map[android.SdkKind]string{
 	android.SdkPublic:       "public-stub-classpath",
 	android.SdkSystem:       "system-stub-classpath",
 	android.SdkTest:         "test-stub-classpath",
 	android.SdkCorePlatform: "core-platform-stub-classpath",
 }

 // ruleToGenerateHiddenAPIStubFlagsFile creates a rule to create a hidden API stub flags file.
 //
 // The rule is initialized but not built so that the caller can modify it and select an appropriate
 // name.
 func ruleToGenerateHiddenAPIStubFlagsFile(ctx android.BuilderContext, outputPath android.OutputPath, bootDexJars android.Paths, sdkKindToPathList map[android.SdkKind]android.Paths) *android.RuleBuilder {
 	// Singleton rule which applies hiddenapi on all boot class path dex files.
 	rule := android.NewRuleBuilder(pctx, ctx)

 	tempPath := tempPathForRestat(ctx, outputPath)

 	command := rule.Command().
 		Tool(ctx.Config().HostToolPath(ctx, "hiddenapi")).
 		Text("list").
 		FlagForEachInput("--boot-dex=", bootDexJars)

 	// Iterate over the sdk kinds in a fixed order.
 	for _, sdkKind := range hiddenAPIRelevantSdkKinds {
 		paths := sdkKindToPathList[sdkKind]
 		if len(paths) > 0 {
 			option := sdkKindToHiddenapiListOption[sdkKind]
 			command.FlagWithInputList("--"+option+"=", paths, ":")
 		}
 	}

 	// Add the output path.
 	command.FlagWithOutput("--out-api-flags=", tempPath)

 	commitChangeForRestat(rule, tempPath, outputPath)
 	return rule
 }

 // HiddenAPIFlagFileProperties contains paths to the flag files that can be used to augment the
 // information obtained from annotations within the source code in order to create the complete set
 // of flags that should be applied to the dex implementation jars on the bootclasspath.
 //
 // Each property contains a list of paths. With the exception of the Unsupported_packages the paths
 // of each property reference a plain text file that contains a java signature per line. The flags
 // for each of those signatures will be updated in a property specific way.
 //
 // The Unsupported_packages property contains a list of paths, each of which is a plain text file
 // with one Java package per line. All members of all classes within that package (but not nested
 // packages) will be updated in a property specific way.
 type HiddenAPIFlagFileProperties struct {
 	// Marks each signature in the referenced files as being unsupported.
 	Unsupported []string `android:"path"`

 	// Marks each signature in the referenced files as being unsupported because it has been removed.
 	// Any conflicts with other flags are ignored.
 	Removed []string `android:"path"`

 	// Marks each signature in the referenced files as being supported only for targetSdkVersion <= R
 	// and low priority.
 	Max_target_r_low_priority []string `android:"path"`

 	// Marks each signature in the referenced files as being supported only for targetSdkVersion <= Q.
 	Max_target_q []string `android:"path"`

 	// Marks each signature in the referenced files as being supported only for targetSdkVersion <= P.
 	Max_target_p []string `android:"path"`

 	// Marks each signature in the referenced files as being supported only for targetSdkVersion <= O
 	// and low priority. Any conflicts with other flags are ignored.
 	Max_target_o_low_priority []string `android:"path"`

 	// Marks each signature in the referenced files as being blocked.
 	Blocked []string `android:"path"`

 	// Marks each signature in every package in the referenced files as being unsupported.
 	Unsupported_packages []string `android:"path"`
 }

 func (p *HiddenAPIFlagFileProperties) hiddenAPIFlagFileInfo(ctx android.ModuleContext) hiddenAPIFlagFileInfo {
 	info := hiddenAPIFlagFileInfo{categoryToPaths: map[*hiddenAPIFlagFileCategory]android.Paths{}}
 	for _, category := range hiddenAPIFlagFileCategories {
 		paths := android.PathsForModuleSrc(ctx, category.propertyValueReader(p))
 		info.categoryToPaths[category] = paths
 	}
 	return info
 }

 type hiddenAPIFlagFileCategory struct {
 	// propertyName is the name of the property for this category.
 	propertyName string

 	// propertyValueReader retrieves the value of the property for this category from the set of
 	// properties.
 	propertyValueReader func(properties *HiddenAPIFlagFileProperties) []string

 	// commandMutator adds the appropriate command line options for this category to the supplied
 	// command
 	commandMutator func(command *android.RuleBuilderCommand, path android.Path)
 }

 var hiddenAPIFlagFileCategories = []*hiddenAPIFlagFileCategory{
 	// See HiddenAPIFlagFileProperties.Unsupported
 	{
 		propertyName: "unsupported",
 		propertyValueReader: func(properties *HiddenAPIFlagFileProperties) []string {
 			return properties.Unsupported
 		},
 		commandMutator: func(command *android.RuleBuilderCommand, path android.Path) {
 			command.FlagWithInput("--unsupported ", path)
 		},
 	},
 	// See HiddenAPIFlagFileProperties.Removed
 	{
 		propertyName: "removed",
 		propertyValueReader: func(properties *HiddenAPIFlagFileProperties) []string {
 			return properties.Removed
 		},
 		commandMutator: func(command *android.RuleBuilderCommand, path android.Path) {
 			command.FlagWithInput("--unsupported ", path).Flag("--ignore-conflicts ").FlagWithArg("--tag ", "removed")
 		},
 	},
 	// See HiddenAPIFlagFileProperties.Max_target_r_low_priority
 	{
 		propertyName: "max_target_r_low_priority",
 		propertyValueReader: func(properties *HiddenAPIFlagFileProperties) []string {
 			return properties.Max_target_r_low_priority
 		},
 		commandMutator: func(command *android.RuleBuilderCommand, path android.Path) {
 			command.FlagWithInput("--max-target-r ", path).FlagWithArg("--tag ", "lo-prio")
 		},
 	},
 	// See HiddenAPIFlagFileProperties.Max_target_q
 	{
 		propertyName: "max_target_q",
 		propertyValueReader: func(properties *HiddenAPIFlagFileProperties) []string {
 			return properties.Max_target_q
 		},
 		commandMutator: func(command *android.RuleBuilderCommand, path android.Path) {
 			command.FlagWithInput("--max-target-q ", path)
 		},
 	},
 	// See HiddenAPIFlagFileProperties.Max_target_p
 	{
 		propertyName: "max_target_p",
 		propertyValueReader: func(properties *HiddenAPIFlagFileProperties) []string {
 			return properties.Max_target_p
 		},
 		commandMutator: func(command *android.RuleBuilderCommand, path android.Path) {
 			command.FlagWithInput("--max-target-p ", path)
 		},
 	},
 	// See HiddenAPIFlagFileProperties.Max_target_o_low_priority
 	{
 		propertyName: "max_target_o_low_priority",
 		propertyValueReader: func(properties *HiddenAPIFlagFileProperties) []string {
 			return properties.Max_target_o_low_priority
 		},
 		commandMutator: func(command *android.RuleBuilderCommand, path android.Path) {
 			command.FlagWithInput("--max-target-o ", path).Flag("--ignore-conflicts ").FlagWithArg("--tag ", "lo-prio")
 		},
 	},
 	// See HiddenAPIFlagFileProperties.Blocked
 	{
 		propertyName: "blocked",
 		propertyValueReader: func(properties *HiddenAPIFlagFileProperties) []string {
 			return properties.Blocked
 		},
 		commandMutator: func(command *android.RuleBuilderCommand, path android.Path) {
 			command.FlagWithInput("--blocked ", path)
 		},
 	},
 	// See HiddenAPIFlagFileProperties.Unsupported_packages
 	{
 		propertyName: "unsupported_packages",
 		propertyValueReader: func(properties *HiddenAPIFlagFileProperties) []string {
 			return properties.Unsupported_packages
 		},
 		commandMutator: func(command *android.RuleBuilderCommand, path android.Path) {
 			command.FlagWithInput("--unsupported ", path).Flag("--packages ")
 		},
 	},
 }

 // hiddenAPIFlagFileInfo contains paths resolved from HiddenAPIFlagFileProperties
 type hiddenAPIFlagFileInfo struct {
 	// categoryToPaths maps from the flag file category to the paths containing information for that
 	// category.
 	categoryToPaths map[*hiddenAPIFlagFileCategory]android.Paths
 }

 func (i *hiddenAPIFlagFileInfo) append(other hiddenAPIFlagFileInfo) {
 	for _, category := range hiddenAPIFlagFileCategories {
 		i.categoryToPaths[category] = append(i.categoryToPaths[category], other.categoryToPaths[category]...)
 	}
 }

 var hiddenAPIFlagFileInfoProvider = blueprint.NewProvider(hiddenAPIFlagFileInfo{})

 // ruleToGenerateHiddenApiFlags creates a rule to create the monolithic hidden API flags from the
 // flags from all the modules, the stub flags, augmented with some additional configuration files.
 //
 // baseFlagsPath is the path to the flags file containing all the information from the stubs plus
 // an entry for every single member in the dex implementation jars of the individual modules. Every
 // signature in any of the other files MUST be included in this file.
 //
 // moduleSpecificFlagsPaths are the paths to the flags files generated by each module using
 // information from the baseFlagsPath as well as from annotations within the source.
 //
 // augmentationInfo is a struct containing paths to files that augment the information provided by
 // the moduleSpecificFlagsPaths.
 // ruleToGenerateHiddenApiFlags creates a rule to create the monolithic hidden API flags from the
 // flags from all the modules, the stub flags, augmented with some additional configuration files.
 //
 // baseFlagsPath is the path to the flags file containing all the information from the stubs plus
 // an entry for every single member in the dex implementation jars of the individual modules. Every
 // signature in any of the other files MUST be included in this file.
 //
 // moduleSpecificFlagsPaths are the paths to the flags files generated by each module using
 // information from the baseFlagsPath as well as from annotations within the source.
 //
 // augmentationInfo is a struct containing paths to files that augment the information provided by
 // the moduleSpecificFlagsPaths.
 func ruleToGenerateHiddenApiFlags(ctx android.BuilderContext, outputPath android.WritablePath, baseFlagsPath android.Path, moduleSpecificFlagsPaths android.Paths, augmentationInfo hiddenAPIFlagFileInfo) {
 	tempPath := tempPathForRestat(ctx, outputPath)
 	rule := android.NewRuleBuilder(pctx, ctx)
 	command := rule.Command().
 		BuiltTool("generate_hiddenapi_lists").
 		FlagWithInput("--csv ", baseFlagsPath).
 		Inputs(moduleSpecificFlagsPaths).
 		FlagWithOutput("--output ", tempPath)

 	// Add the options for the different categories of flag files.
 	for _, category := range hiddenAPIFlagFileCategories {
 		paths := augmentationInfo.categoryToPaths[category]
 		for _, path := range paths {
 			category.commandMutator(command, path)
 		}
 	}

 	commitChangeForRestat(rule, tempPath, outputPath)

 	rule.Build("hiddenAPIFlagsFile", "hiddenapi flags")
 }
	// Copyright (C) 2021 The Android Open Source Project
	//
	// 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 (
	"android/soong/android"
	"github.com/google/blueprint"
	)

	// Contains support for processing hiddenAPI in a modular fashion.

	type hiddenAPIStubsDependencyTag struct {
	blueprint.BaseDependencyTag
	sdkKind android.SdkKind
	}

	func (b hiddenAPIStubsDependencyTag) ExcludeFromApexContents() {
	}

	func (b hiddenAPIStubsDependencyTag) ReplaceSourceWithPrebuilt() bool {
	return false
	}

	// Avoid having to make stubs content explicitly visible to dependent modules.
	//
	// This is a temporary workaround to make it easier to migrate to bootclasspath_fragment modules
	// with proper dependencies.
	// TODO(b/177892522): Remove this and add needed visibility.
	func (b hiddenAPIStubsDependencyTag) ExcludeFromVisibilityEnforcement() {
	}

	var _ android.ExcludeFromVisibilityEnforcementTag = hiddenAPIStubsDependencyTag{}
	var _ android.ReplaceSourceWithPrebuilt = hiddenAPIStubsDependencyTag{}
	var _ android.ExcludeFromApexContentsTag = hiddenAPIStubsDependencyTag{}

	// hiddenAPIRelevantSdkKinds lists all the android.SdkKind instances that are needed by the hidden
	// API processing.
	var hiddenAPIRelevantSdkKinds = []android.SdkKind{
	android.SdkPublic,
	android.SdkSystem,
	android.SdkTest,
	android.SdkCorePlatform,
	}

	// hiddenAPIComputeMonolithicStubLibModules computes the set of module names that provide stubs
	// needed to produce the hidden API monolithic stub flags file.
	func hiddenAPIComputeMonolithicStubLibModules(config android.Config) map[android.SdkKind][]string {
	var publicStubModules []string
	var systemStubModules []string
	var testStubModules []string
	var corePlatformStubModules []string

	if config.AlwaysUsePrebuiltSdks() {
	// Build configuration mandates using prebuilt stub modules
	publicStubModules = append(publicStubModules, "sdk_public_current_android")
	systemStubModules = append(systemStubModules, "sdk_system_current_android")
	testStubModules = append(testStubModules, "sdk_test_current_android")
	} else {
	// Use stub modules built from source
	publicStubModules = append(publicStubModules, "android_stubs_current")
	systemStubModules = append(systemStubModules, "android_system_stubs_current")
	testStubModules = append(testStubModules, "android_test_stubs_current")
	}
	// We do not have prebuilts of the core platform api yet
	corePlatformStubModules = append(corePlatformStubModules, "legacy.core.platform.api.stubs")

	// Allow products to define their own stubs for custom product jars that apps can use.
	publicStubModules = append(publicStubModules, config.ProductHiddenAPIStubs()...)
	systemStubModules = append(systemStubModules, config.ProductHiddenAPIStubsSystem()...)
	testStubModules = append(testStubModules, config.ProductHiddenAPIStubsTest()...)
	if config.IsEnvTrue("EMMA_INSTRUMENT") {
	publicStubModules = append(publicStubModules, "jacoco-stubs")
	}

	m := map[android.SdkKind][]string{}
	m[android.SdkPublic] = publicStubModules
	m[android.SdkSystem] = systemStubModules
	m[android.SdkTest] = testStubModules
	m[android.SdkCorePlatform] = corePlatformStubModules
	return m
	}

	// hiddenAPIAddStubLibDependencies adds dependencies onto the modules specified in
	// sdkKindToStubLibModules. It adds them in a well known order and uses an SdkKind specific tag to
	// identify the source of the dependency.
	func hiddenAPIAddStubLibDependencies(ctx android.BottomUpMutatorContext, sdkKindToStubLibModules map[android.SdkKind][]string) {
	module := ctx.Module()
	for _, sdkKind := range hiddenAPIRelevantSdkKinds {
	modules := sdkKindToStubLibModules[sdkKind]
	ctx.AddDependency(module, hiddenAPIStubsDependencyTag{sdkKind: sdkKind}, modules...)
	}
	}

	// hiddenAPIGatherStubLibDexJarPaths gathers the paths to the dex jars from the dependencies added
	// in hiddenAPIAddStubLibDependencies.
	func hiddenAPIGatherStubLibDexJarPaths(ctx android.ModuleContext) map[android.SdkKind]android.Paths {
	m := map[android.SdkKind]android.Paths{}
	ctx.VisitDirectDepsIf(isActiveModule, func(module android.Module) {
	tag := ctx.OtherModuleDependencyTag(module)
	if hiddenAPIStubsTag, ok := tag.(hiddenAPIStubsDependencyTag); ok {
	kind := hiddenAPIStubsTag.sdkKind
	dexJar := hiddenAPIRetrieveDexJarBuildPath(ctx, module)
	if dexJar != nil {
	m[kind] = append(m[kind], dexJar)
	}
	}
	})
	return m
	}

	// hiddenAPIRetrieveDexJarBuildPath retrieves the DexJarBuildPath from the specified module, if
	// available, or reports an error.
	func hiddenAPIRetrieveDexJarBuildPath(ctx android.ModuleContext, module android.Module) android.Path {
	if j, ok := module.(UsesLibraryDependency); ok {
	dexJar := j.DexJarBuildPath()
	if dexJar != nil {
	return dexJar
	}
	ctx.ModuleErrorf("dependency %s does not provide a dex jar, consider setting compile_dex: true", module)
	} else {
	ctx.ModuleErrorf("dependency %s of module type %s does not support providing a dex jar", module, ctx.OtherModuleType(module))
	}
	return nil
	}

	var sdkKindToHiddenapiListOption = map[android.SdkKind]string{
	android.SdkPublic: "public-stub-classpath",
	android.SdkSystem: "system-stub-classpath",
	android.SdkTest: "test-stub-classpath",
	android.SdkCorePlatform: "core-platform-stub-classpath",
	}

	// ruleToGenerateHiddenAPIStubFlagsFile creates a rule to create a hidden API stub flags file.
	//
	// The rule is initialized but not built so that the caller can modify it and select an appropriate
	// name.
	func ruleToGenerateHiddenAPIStubFlagsFile(ctx android.BuilderContext, outputPath android.OutputPath, bootDexJars android.Paths, sdkKindToPathList map[android.SdkKind]android.Paths) *android.RuleBuilder {
	// Singleton rule which applies hiddenapi on all boot class path dex files.
	rule := android.NewRuleBuilder(pctx, ctx)

	tempPath := tempPathForRestat(ctx, outputPath)

	command := rule.Command().
	Tool(ctx.Config().HostToolPath(ctx, "hiddenapi")).
	Text("list").
	FlagForEachInput("--boot-dex=", bootDexJars)

	// Iterate over the sdk kinds in a fixed order.
	for _, sdkKind := range hiddenAPIRelevantSdkKinds {
	paths := sdkKindToPathList[sdkKind]
	if len(paths) > 0 {
	option := sdkKindToHiddenapiListOption[sdkKind]
	command.FlagWithInputList("--"+option+"=", paths, ":")
	}
	}

	// Add the output path.
	command.FlagWithOutput("--out-api-flags=", tempPath)

	commitChangeForRestat(rule, tempPath, outputPath)
	return rule
	}

	// HiddenAPIFlagFileProperties contains paths to the flag files that can be used to augment the
	// information obtained from annotations within the source code in order to create the complete set
	// of flags that should be applied to the dex implementation jars on the bootclasspath.
	//
	// Each property contains a list of paths. With the exception of the Unsupported_packages the paths
	// of each property reference a plain text file that contains a java signature per line. The flags
	// for each of those signatures will be updated in a property specific way.
	//
	// The Unsupported_packages property contains a list of paths, each of which is a plain text file
	// with one Java package per line. All members of all classes within that package (but not nested
	// packages) will be updated in a property specific way.
	type HiddenAPIFlagFileProperties struct {
	// Marks each signature in the referenced files as being unsupported.
	Unsupported []string `android:"path"`

	// Marks each signature in the referenced files as being unsupported because it has been removed.
	// Any conflicts with other flags are ignored.
	Removed []string `android:"path"`

	// Marks each signature in the referenced files as being supported only for targetSdkVersion <= R
	// and low priority.
	Max_target_r_low_priority []string `android:"path"`

	// Marks each signature in the referenced files as being supported only for targetSdkVersion <= Q.
	Max_target_q []string `android:"path"`

	// Marks each signature in the referenced files as being supported only for targetSdkVersion <= P.
	Max_target_p []string `android:"path"`

	// Marks each signature in the referenced files as being supported only for targetSdkVersion <= O
	// and low priority. Any conflicts with other flags are ignored.
	Max_target_o_low_priority []string `android:"path"`

	// Marks each signature in the referenced files as being blocked.
	Blocked []string `android:"path"`

	// Marks each signature in every package in the referenced files as being unsupported.
	Unsupported_packages []string `android:"path"`
	}

	func (p *HiddenAPIFlagFileProperties) hiddenAPIFlagFileInfo(ctx android.ModuleContext) hiddenAPIFlagFileInfo {
	info := hiddenAPIFlagFileInfo{categoryToPaths: map[*hiddenAPIFlagFileCategory]android.Paths{}}
	for _, category := range hiddenAPIFlagFileCategories {
	paths := android.PathsForModuleSrc(ctx, category.propertyValueReader(p))
	info.categoryToPaths[category] = paths
	}
	return info
	}

	type hiddenAPIFlagFileCategory struct {
	// propertyName is the name of the property for this category.
	propertyName string

	// propertyValueReader retrieves the value of the property for this category from the set of
	// properties.
	propertyValueReader func(properties *HiddenAPIFlagFileProperties) []string

	// commandMutator adds the appropriate command line options for this category to the supplied
	// command
	commandMutator func(command *android.RuleBuilderCommand, path android.Path)
	}

	var hiddenAPIFlagFileCategories = []*hiddenAPIFlagFileCategory{
	// See HiddenAPIFlagFileProperties.Unsupported
	{
	propertyName: "unsupported",
	propertyValueReader: func(properties *HiddenAPIFlagFileProperties) []string {
	return properties.Unsupported
	},
	commandMutator: func(command *android.RuleBuilderCommand, path android.Path) {
	command.FlagWithInput("--unsupported ", path)
	},
	},
	// See HiddenAPIFlagFileProperties.Removed
	{
	propertyName: "removed",
	propertyValueReader: func(properties *HiddenAPIFlagFileProperties) []string {
	return properties.Removed
	},
	commandMutator: func(command *android.RuleBuilderCommand, path android.Path) {
	command.FlagWithInput("--unsupported ", path).Flag("--ignore-conflicts ").FlagWithArg("--tag ", "removed")
	},
	},
	// See HiddenAPIFlagFileProperties.Max_target_r_low_priority
	{
	propertyName: "max_target_r_low_priority",
	propertyValueReader: func(properties *HiddenAPIFlagFileProperties) []string {
	return properties.Max_target_r_low_priority
	},
	commandMutator: func(command *android.RuleBuilderCommand, path android.Path) {
	command.FlagWithInput("--max-target-r ", path).FlagWithArg("--tag ", "lo-prio")
	},
	},
	// See HiddenAPIFlagFileProperties.Max_target_q
	{
	propertyName: "max_target_q",
	propertyValueReader: func(properties *HiddenAPIFlagFileProperties) []string {
	return properties.Max_target_q
	},
	commandMutator: func(command *android.RuleBuilderCommand, path android.Path) {
	command.FlagWithInput("--max-target-q ", path)
	},
	},
	// See HiddenAPIFlagFileProperties.Max_target_p
	{
	propertyName: "max_target_p",
	propertyValueReader: func(properties *HiddenAPIFlagFileProperties) []string {
	return properties.Max_target_p
	},
	commandMutator: func(command *android.RuleBuilderCommand, path android.Path) {
	command.FlagWithInput("--max-target-p ", path)
	},
	},
	// See HiddenAPIFlagFileProperties.Max_target_o_low_priority
	{
	propertyName: "max_target_o_low_priority",
	propertyValueReader: func(properties *HiddenAPIFlagFileProperties) []string {
	return properties.Max_target_o_low_priority
	},
	commandMutator: func(command *android.RuleBuilderCommand, path android.Path) {
	command.FlagWithInput("--max-target-o ", path).Flag("--ignore-conflicts ").FlagWithArg("--tag ", "lo-prio")
	},
	},
	// See HiddenAPIFlagFileProperties.Blocked
	{
	propertyName: "blocked",
	propertyValueReader: func(properties *HiddenAPIFlagFileProperties) []string {
	return properties.Blocked
	},
	commandMutator: func(command *android.RuleBuilderCommand, path android.Path) {
	command.FlagWithInput("--blocked ", path)
	},
	},
	// See HiddenAPIFlagFileProperties.Unsupported_packages
	{
	propertyName: "unsupported_packages",
	propertyValueReader: func(properties *HiddenAPIFlagFileProperties) []string {
	return properties.Unsupported_packages
	},
	commandMutator: func(command *android.RuleBuilderCommand, path android.Path) {
	command.FlagWithInput("--unsupported ", path).Flag("--packages ")
	},
	},
	}

	// hiddenAPIFlagFileInfo contains paths resolved from HiddenAPIFlagFileProperties
	type hiddenAPIFlagFileInfo struct {
	// categoryToPaths maps from the flag file category to the paths containing information for that
	// category.
	categoryToPaths map[*hiddenAPIFlagFileCategory]android.Paths
	}

	func (i *hiddenAPIFlagFileInfo) append(other hiddenAPIFlagFileInfo) {
	for _, category := range hiddenAPIFlagFileCategories {
	i.categoryToPaths[category] = append(i.categoryToPaths[category], other.categoryToPaths[category]...)
	}
	}

	var hiddenAPIFlagFileInfoProvider = blueprint.NewProvider(hiddenAPIFlagFileInfo{})

	// ruleToGenerateHiddenApiFlags creates a rule to create the monolithic hidden API flags from the
	// flags from all the modules, the stub flags, augmented with some additional configuration files.
	//
	// baseFlagsPath is the path to the flags file containing all the information from the stubs plus
	// an entry for every single member in the dex implementation jars of the individual modules. Every
	// signature in any of the other files MUST be included in this file.
	//
	// moduleSpecificFlagsPaths are the paths to the flags files generated by each module using
	// information from the baseFlagsPath as well as from annotations within the source.
	//
	// augmentationInfo is a struct containing paths to files that augment the information provided by
	// the moduleSpecificFlagsPaths.
	// ruleToGenerateHiddenApiFlags creates a rule to create the monolithic hidden API flags from the
	// flags from all the modules, the stub flags, augmented with some additional configuration files.
	//
	// baseFlagsPath is the path to the flags file containing all the information from the stubs plus
	// an entry for every single member in the dex implementation jars of the individual modules. Every
	// signature in any of the other files MUST be included in this file.
	//
	// moduleSpecificFlagsPaths are the paths to the flags files generated by each module using
	// information from the baseFlagsPath as well as from annotations within the source.
	//
	// augmentationInfo is a struct containing paths to files that augment the information provided by
	// the moduleSpecificFlagsPaths.
	func ruleToGenerateHiddenApiFlags(ctx android.BuilderContext, outputPath android.WritablePath, baseFlagsPath android.Path, moduleSpecificFlagsPaths android.Paths, augmentationInfo hiddenAPIFlagFileInfo) {
	tempPath := tempPathForRestat(ctx, outputPath)
	rule := android.NewRuleBuilder(pctx, ctx)
	command := rule.Command().
	BuiltTool("generate_hiddenapi_lists").
	FlagWithInput("--csv ", baseFlagsPath).
	Inputs(moduleSpecificFlagsPaths).
	FlagWithOutput("--output ", tempPath)

	// Add the options for the different categories of flag files.
	for _, category := range hiddenAPIFlagFileCategories {
	paths := augmentationInfo.categoryToPaths[category]
	for _, path := range paths {
	category.commandMutator(command, path)
	}
	}

	commitChangeForRestat(rule, tempPath, outputPath)

	rule.Build("hiddenAPIFlagsFile", "hiddenapi flags")
	}