cc/library.go

// Copyright 2016 Google Inc. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package cc

import (
	"fmt"
	"io"
	"path/filepath"
	"regexp"
	"slices"
	"strconv"
	"strings"
	"sync"

	"android/soong/android"

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

// LibraryProperties is a collection of properties shared by cc library rules/cc.
type LibraryProperties struct {
	// local file name to pass to the linker as -unexported_symbols_list
	Unexported_symbols_list *string `android:"path,arch_variant"`
	// local file name to pass to the linker as -force_symbols_not_weak_list
	Force_symbols_not_weak_list *string `android:"path,arch_variant"`
	// local file name to pass to the linker as -force_symbols_weak_list
	Force_symbols_weak_list *string `android:"path,arch_variant"`

	// rename host libraries to prevent overlap with system installed libraries
	Unique_host_soname *bool

	Aidl struct {
		// export headers generated from .aidl sources
		Export_aidl_headers *bool
	}

	Proto struct {
		// export headers generated from .proto sources
		Export_proto_headers *bool
	}

	Sysprop struct {
		// Whether platform owns this sysprop library.
		Platform *bool
	} `blueprint:"mutated"`

	Static_ndk_lib *bool

	// Generate stubs to make this library accessible to APEXes.
	Stubs struct {
		// Relative path to the symbol map. The symbol map provides the list of
		// symbols that are exported for stubs variant of this library.
		Symbol_file *string `android:"path,arch_variant"`

		// List versions to generate stubs libs for. The version name "current" is always
		// implicitly added.
		Versions []string

		// Whether to not require the implementation of the library to be installed if a
		// client of the stubs is installed. Defaults to true; set to false if the
		// implementation is made available by some other means, e.g. in a Microdroid
		// virtual machine.
		Implementation_installable *bool
	} `android:"arch_variant"`

	// set the name of the output
	Stem *string `android:"arch_variant"`

	// set suffix of the name of the output
	Suffix *string `android:"arch_variant"`

	// Properties for ABI compatibility checker.
	Header_abi_checker headerAbiCheckerProperties

	Target struct {
		Vendor, Product struct {
			// set suffix of the name of the output
			Suffix *string `android:"arch_variant"`

			Header_abi_checker headerAbiCheckerProperties

			// Disable stubs for vendor/product variants
			// This is a workaround to keep `stubs` only for "core" variant (not product/vendor).
			// It would be nice if we could put `stubs` into a `target: { core: {} }`
			// block but it's not supported in soong yet. This could be removed/simplified once we have
			// a better syntax.
			No_stubs bool
		}

		Platform struct {
			Header_abi_checker headerAbiCheckerProperties
		}
	}

	// Names of modules to be overridden. Listed modules can only be other shared libraries
	// (in Make or Soong).
	// This does not completely prevent installation of the overridden libraries, but if both
	// binaries would be installed by default (in PRODUCT_PACKAGES) the other library will be removed
	// from PRODUCT_PACKAGES.
	Overrides []string

	// Inject boringssl hash into the shared library.  This is only intended for use by external/boringssl.
	Inject_bssl_hash *bool `android:"arch_variant"`

	// If this is an LLNDK library, properties to describe the LLNDK stubs.  Will be copied from
	// the module pointed to by llndk_stubs if it is set.
	Llndk llndkLibraryProperties `android:"arch_variant"`

	// If this is a vendor public library, properties to describe the vendor public library stubs.
	Vendor_public_library vendorPublicLibraryProperties
}

// StaticProperties is a properties stanza to affect only attributes of the "static" variants of a
// library module.
type StaticProperties struct {
	Static StaticOrSharedProperties `android:"arch_variant"`
}

// SharedProperties is a properties stanza to affect only attributes of the "shared" variants of a
// library module.
type SharedProperties struct {
	Shared StaticOrSharedProperties `android:"arch_variant"`
}

// StaticOrSharedProperties is an embedded struct representing properties to affect attributes of
// either only the "static" variants or only the "shared" variants of a library module. These override
// the base properties of the same name.
// Use `StaticProperties` or `SharedProperties`, depending on which variant is needed.
// `StaticOrSharedProperties` exists only to avoid duplication.
type StaticOrSharedProperties struct {
	Srcs proptools.Configurable[[]string] `android:"path,arch_variant"`

	Tidy_disabled_srcs []string `android:"path,arch_variant"`

	Tidy_timeout_srcs []string `android:"path,arch_variant"`

	Sanitized Sanitized `android:"arch_variant"`

	Cflags proptools.Configurable[[]string] `android:"arch_variant"`

	Enabled            *bool                            `android:"arch_variant"`
	Whole_static_libs  proptools.Configurable[[]string] `android:"arch_variant"`
	Static_libs        proptools.Configurable[[]string] `android:"arch_variant"`
	Shared_libs        proptools.Configurable[[]string] `android:"arch_variant"`
	System_shared_libs []string                         `android:"arch_variant"`

	Export_shared_lib_headers []string `android:"arch_variant"`
	Export_static_lib_headers []string `android:"arch_variant"`

	Apex_available []string `android:"arch_variant"`

	Installable *bool `android:"arch_variant"`
}

type LibraryMutatedProperties struct {
	// Build a static variant
	BuildStatic bool `blueprint:"mutated"`
	// Build a shared variant
	BuildShared bool `blueprint:"mutated"`
	// This variant is shared
	VariantIsShared bool `blueprint:"mutated"`
	// This variant is static
	VariantIsStatic bool `blueprint:"mutated"`

	// This variant is a stubs lib
	BuildStubs bool `blueprint:"mutated"`
	// This variant is the latest version
	IsLatestVersion bool `blueprint:"mutated"`
	// Version of the stubs lib
	StubsVersion string `blueprint:"mutated"`
	// List of all stubs versions associated with an implementation lib
	AllStubsVersions []string `blueprint:"mutated"`
}

type FlagExporterProperties struct {
	// list of directories relative to the Blueprints file that will
	// be added to the include path (using -I) for this module and any module that links
	// against this module.  Directories listed in export_include_dirs do not need to be
	// listed in local_include_dirs.
	Export_include_dirs proptools.Configurable[[]string] `android:"arch_variant,variant_prepend"`

	// list of directories that will be added to the system include path
	// using -isystem for this module and any module that links against this module.
	Export_system_include_dirs []string `android:"arch_variant,variant_prepend"`

	// list of plain cc flags to be used for any module that links against this module.
	Export_cflags []string  `android:"arch_variant"`

	Target struct {
		Vendor, Product struct {
			// list of exported include directories, like
			// export_include_dirs, that will be applied to
			// vendor or product variant of this library.
			// This will overwrite any other declarations.
			Override_export_include_dirs []string
		}
	}
}

func init() {
	RegisterLibraryBuildComponents(android.InitRegistrationContext)
}

func RegisterLibraryBuildComponents(ctx android.RegistrationContext) {
	ctx.RegisterModuleType("cc_library_static", LibraryStaticFactory)
	ctx.RegisterModuleType("cc_library_shared", LibrarySharedFactory)
	ctx.RegisterModuleType("cc_library", LibraryFactory)
	ctx.RegisterModuleType("cc_library_host_static", LibraryHostStaticFactory)
	ctx.RegisterModuleType("cc_library_host_shared", LibraryHostSharedFactory)
}

// cc_library creates both static and/or shared libraries for a device and/or
// host. By default, a cc_library has a single variant that targets the device.
// Specifying `host_supported: true` also creates a library that targets the
// host.
func LibraryFactory() android.Module {
	module, _ := NewLibrary(android.HostAndDeviceSupported)
	// Can be used as both a static and a shared library.
	module.sdkMemberTypes = []android.SdkMemberType{
		sharedLibrarySdkMemberType,
		staticLibrarySdkMemberType,
		staticAndSharedLibrarySdkMemberType,
	}
	return module.Init()
}

// cc_library_static creates a static library for a device and/or host binary.
func LibraryStaticFactory() android.Module {
	module, library := NewLibrary(android.HostAndDeviceSupported)
	library.BuildOnlyStatic()
	module.sdkMemberTypes = []android.SdkMemberType{staticLibrarySdkMemberType}
	return module.Init()
}

// cc_library_shared creates a shared library for a device and/or host.
func LibrarySharedFactory() android.Module {
	module, library := NewLibrary(android.HostAndDeviceSupported)
	library.BuildOnlyShared()
	module.sdkMemberTypes = []android.SdkMemberType{sharedLibrarySdkMemberType}
	return module.Init()
}

// cc_library_host_static creates a static library that is linkable to a host
// binary.
func LibraryHostStaticFactory() android.Module {
	module, library := NewLibrary(android.HostSupported)
	library.BuildOnlyStatic()
	module.sdkMemberTypes = []android.SdkMemberType{staticLibrarySdkMemberType}
	return module.Init()
}

// cc_library_host_shared creates a shared library that is usable on a host.
func LibraryHostSharedFactory() android.Module {
	module, library := NewLibrary(android.HostSupported)
	library.BuildOnlyShared()
	module.sdkMemberTypes = []android.SdkMemberType{sharedLibrarySdkMemberType}
	return module.Init()
}

// flagExporter is a separated portion of libraryDecorator pertaining to exported
// include paths and flags. Keeping this dependency-related information separate
// from the rest of library information is helpful in keeping data more structured
// and explicit.
type flagExporter struct {
	Properties FlagExporterProperties

	dirs         android.Paths // Include directories to be included with -I
	systemDirs   android.Paths // System include directories to be included with -isystem
	flags        []string      // Exported raw flags.
	deps         android.Paths
	headers      android.Paths
	rustRlibDeps []RustRlibDep
}

// exportedIncludes returns the effective include paths for this module and
// any module that links against this module. This is obtained from
// the export_include_dirs property in the appropriate target stanza.
func (f *flagExporter) exportedIncludes(ctx ModuleContext) android.Paths {
	if ctx.inVendor() && f.Properties.Target.Vendor.Override_export_include_dirs != nil {
		return android.PathsForModuleSrc(ctx, f.Properties.Target.Vendor.Override_export_include_dirs)
	}
	if ctx.inProduct() && f.Properties.Target.Product.Override_export_include_dirs != nil {
		return android.PathsForModuleSrc(ctx, f.Properties.Target.Product.Override_export_include_dirs)
	}
	return android.PathsForModuleSrc(ctx, f.Properties.Export_include_dirs.GetOrDefault(ctx, nil))
}

func (f *flagExporter) exportedSystemIncludes(ctx ModuleContext) android.Paths {
	return android.PathsForModuleSrc(ctx, f.Properties.Export_system_include_dirs)
}

// exportIncludes registers the include directories and system include directories to be exported
// transitively to modules depending on this module.
func (f *flagExporter) exportIncludes(ctx ModuleContext) {
	f.dirs = append(f.dirs, f.exportedIncludes(ctx)...)
	f.systemDirs = append(f.systemDirs, android.PathsForModuleSrc(ctx, f.Properties.Export_system_include_dirs)...)
}

func (f *flagExporter) exportExtraFlags(ctx ModuleContext) {
	f.flags = append(f.flags, f.Properties.Export_cflags...)
}

// exportIncludesAsSystem registers the include directories and system include directories to be
// exported transitively both as system include directories to modules depending on this module.
func (f *flagExporter) exportIncludesAsSystem(ctx ModuleContext) {
	// all dirs are force exported as system
	f.systemDirs = append(f.systemDirs, f.exportedIncludes(ctx)...)
	f.systemDirs = append(f.systemDirs, android.PathsForModuleSrc(ctx, f.Properties.Export_system_include_dirs)...)
}

// reexportDirs registers the given directories as include directories to be exported transitively
// to modules depending on this module.
func (f *flagExporter) reexportDirs(dirs ...android.Path) {
	f.dirs = append(f.dirs, dirs...)
}

// reexportSystemDirs registers the given directories as system include directories
// to be exported transitively to modules depending on this module.
func (f *flagExporter) reexportSystemDirs(dirs ...android.Path) {
	f.systemDirs = append(f.systemDirs, dirs...)
}

// reexportFlags registers the flags to be exported transitively to modules depending on this
// module.
func (f *flagExporter) reexportFlags(flags ...string) {
	if android.PrefixInList(flags, "-I") || android.PrefixInList(flags, "-isystem") {
		panic(fmt.Errorf("Exporting invalid flag %q: "+
			"use reexportDirs or reexportSystemDirs to export directories", flag))
	}
	f.flags = append(f.flags, flags...)
}

func (f *flagExporter) reexportDeps(deps ...android.Path) {
	f.deps = append(f.deps, deps...)
}

func (f *flagExporter) reexportRustStaticDeps(deps ...RustRlibDep) {
	f.rustRlibDeps = append(f.rustRlibDeps, deps...)
}

// addExportedGeneratedHeaders does nothing but collects generated header files.
// This can be differ to exportedDeps which may contain phony files to minimize ninja.
func (f *flagExporter) addExportedGeneratedHeaders(headers ...android.Path) {
	f.headers = append(f.headers, headers...)
}

func (f *flagExporter) setProvider(ctx android.ModuleContext) {
	android.SetProvider(ctx, FlagExporterInfoProvider, FlagExporterInfo{
		// Comes from Export_include_dirs property, and those of exported transitive deps
		IncludeDirs: android.FirstUniquePaths(f.dirs),
		// Comes from Export_system_include_dirs property, and those of exported transitive deps
		SystemIncludeDirs: android.FirstUniquePaths(f.systemDirs),
		// Used in very few places as a one-off way of adding extra defines.
		Flags: f.flags,
		// Used sparingly, for extra files that need to be explicitly exported to dependers,
		// or for phony files to minimize ninja.
		Deps: f.deps,
		// Used for exporting rlib deps of static libraries to dependents.
		RustRlibDeps: f.rustRlibDeps,
		// For exported generated headers, such as exported aidl headers, proto headers, or
		// sysprop headers.
		GeneratedHeaders: f.headers,
	})
}

// libraryDecorator wraps baseCompiler, baseLinker and baseInstaller to provide library-specific
// functionality: static vs. shared linkage, reusing object files for shared libraries
type libraryDecorator struct {
	Properties        LibraryProperties
	StaticProperties  StaticProperties
	SharedProperties  SharedProperties
	MutatedProperties LibraryMutatedProperties

	// For reusing static library objects for shared library
	reuseObjects Objects

	// table-of-contents file to optimize out relinking when possible
	tocFile android.OptionalPath

	flagExporter
	flagExporterInfo *FlagExporterInfo
	stripper         Stripper

	// For whole_static_libs
	objects                      Objects
	wholeStaticLibsFromPrebuilts android.Paths

	// Uses the module's name if empty, but can be overridden. Does not include
	// shlib suffix.
	libName string

	sabi *sabi

	// Output archive of gcno coverage information files
	coverageOutputFile android.OptionalPath

	// Source Abi Diff
	sAbiDiff android.Paths

	// Location of the static library in the sysroot. Empty if the library is
	// not included in the NDK.
	ndkSysrootPath android.Path

	// Location of the linked, unstripped library for shared libraries
	unstrippedOutputFile android.Path
	// Location of the linked, stripped library for shared libraries, strip: "all"
	strippedAllOutputFile android.Path

	// Location of the file that should be copied to dist dir when requested
	distFile android.Path

	versionScriptPath android.OptionalPath

	postInstallCmds []string

	skipAPIDefine bool

	// Decorated interfaces
	*baseCompiler
	*baseLinker
	*baseInstaller

	apiListCoverageXmlPath android.ModuleOutPath

	// Path to the file containing the APIs exported by this library
	stubsSymbolFilePath android.Path
}

// linkerProps returns the list of properties structs relevant for this library. (For example, if
// the library is cc_shared_library, then static-library properties are omitted.)
func (library *libraryDecorator) linkerProps() []interface{} {
	var props []interface{}
	props = append(props, library.baseLinker.linkerProps()...)
	props = append(props,
		&library.Properties,
		&library.MutatedProperties,
		&library.flagExporter.Properties,
		&library.stripper.StripProperties)

	if library.MutatedProperties.BuildShared {
		props = append(props, &library.SharedProperties)
	}
	if library.MutatedProperties.BuildStatic {
		props = append(props, &library.StaticProperties)
	}

	return props
}

// linkerFlags takes a Flags struct and augments it to contain linker flags that are defined by this
// library, or that are implied by attributes of this library (such as whether this library is a
// shared library).
func (library *libraryDecorator) linkerFlags(ctx ModuleContext, flags Flags) Flags {
	flags = library.baseLinker.linkerFlags(ctx, flags)

	// MinGW spits out warnings about -fPIC even for -fpie?!) being ignored because
	// all code is position independent, and then those warnings get promoted to
	// errors.
	if !ctx.Windows() {
		flags.Global.CFlags = append(flags.Global.CFlags, "-fPIC")
	}

	if library.static() {
		flags.Local.CFlags = append(flags.Local.CFlags, library.StaticProperties.Static.Cflags.GetOrDefault(ctx, nil)...)
	} else if library.shared() {
		flags.Local.CFlags = append(flags.Local.CFlags, library.SharedProperties.Shared.Cflags.GetOrDefault(ctx, nil)...)
	}

	if library.shared() {
		libName := library.getLibName(ctx)
		var f []string
		if ctx.toolchain().Bionic() {
			f = append(f,
				"-nostdlib",
				"-Wl,--gc-sections",
			)
		}

		if ctx.Darwin() {
			f = append(f,
				"-dynamiclib",
				"-install_name @rpath/"+libName+flags.Toolchain.ShlibSuffix(),
			)
			if ctx.Arch().ArchType == android.X86 {
				f = append(f,
					"-read_only_relocs suppress",
				)
			}
		} else {
			f = append(f, "-shared")
			if !ctx.Windows() {
				f = append(f, "-Wl,-soname,"+libName+flags.Toolchain.ShlibSuffix())
			}
		}

		flags.Global.LdFlags = append(flags.Global.LdFlags, f...)
	}

	return flags
}

// compilerFlags takes a Flags and augments it to contain compile flags from global values,
// per-target values, module type values, per-module Blueprints properties, extra flags from
// `flags`, and generated sources from `deps`.
func (library *libraryDecorator) compilerFlags(ctx ModuleContext, flags Flags, deps PathDeps) Flags {
	exportIncludeDirs := library.flagExporter.exportedIncludes(ctx)
	if len(exportIncludeDirs) > 0 {
		f := includeDirsToFlags(exportIncludeDirs)
		flags.Local.CommonFlags = append(flags.Local.CommonFlags, f)
		flags.Local.YasmFlags = append(flags.Local.YasmFlags, f)
	}

	flags = library.baseCompiler.compilerFlags(ctx, flags, deps)
	if ctx.IsLlndk() {
		// LLNDK libraries ignore most of the properties on the cc_library and use the
		// LLNDK-specific properties instead.
		// Wipe all the module-local properties, leaving only the global properties.
		flags.Local = LocalOrGlobalFlags{}
	}
	if library.buildStubs() {
		// Remove -include <file> when compiling stubs. Otherwise, the force included
		// headers might cause conflicting types error with the symbols in the
		// generated stubs source code. e.g.
		// double acos(double); // in header
		// void acos() {} // in the generated source code
		removeInclude := func(flags []string) []string {
			ret := flags[:0]
			for _, f := range flags {
				if strings.HasPrefix(f, "-include ") {
					continue
				}
				ret = append(ret, f)
			}
			return ret
		}
		flags.Local.CommonFlags = removeInclude(flags.Local.CommonFlags)
		flags.Local.CFlags = removeInclude(flags.Local.CFlags)

		flags = addStubLibraryCompilerFlags(flags)
	}
	return flags
}

func (library *libraryDecorator) getHeaderAbiCheckerProperties(ctx android.BaseModuleContext) headerAbiCheckerProperties {
	m := ctx.Module().(*Module)
	variantProps := &library.Properties.Target.Platform.Header_abi_checker
	if m.InVendor() {
		variantProps = &library.Properties.Target.Vendor.Header_abi_checker
	} else if m.InProduct() {
		variantProps = &library.Properties.Target.Product.Header_abi_checker
	}
	props := library.Properties.Header_abi_checker
	err := proptools.AppendProperties(&props, variantProps, nil)
	if err != nil {
		ctx.ModuleErrorf("Cannot merge headerAbiCheckerProperties: %s", err.Error())
	}
	return props
}

func (library *libraryDecorator) compile(ctx ModuleContext, flags Flags, deps PathDeps) Objects {
	if ctx.IsLlndk() {
		vendorApiLevel := ctx.Config().VendorApiLevel()
		if vendorApiLevel == "" {
			// TODO(b/321892570): Some tests relying on old fixtures which
			// doesn't set vendorApiLevel. Needs to fix them.
			vendorApiLevel = ctx.Config().PlatformSdkVersion().String()
		}
		// This is the vendor variant of an LLNDK library, build the LLNDK stubs.
		nativeAbiResult := parseNativeAbiDefinition(ctx,
			String(library.Properties.Llndk.Symbol_file),
			android.ApiLevelOrPanic(ctx, vendorApiLevel), "--llndk")
		objs := compileStubLibrary(ctx, flags, nativeAbiResult.stubSrc)
		if !Bool(library.Properties.Llndk.Unversioned) {
			library.versionScriptPath = android.OptionalPathForPath(
				nativeAbiResult.versionScript)
		}
		return objs
	}
	if ctx.IsVendorPublicLibrary() {
		nativeAbiResult := parseNativeAbiDefinition(ctx,
			String(library.Properties.Vendor_public_library.Symbol_file),
			android.FutureApiLevel, "")
		objs := compileStubLibrary(ctx, flags, nativeAbiResult.stubSrc)
		if !Bool(library.Properties.Vendor_public_library.Unversioned) {
			library.versionScriptPath = android.OptionalPathForPath(nativeAbiResult.versionScript)
		}
		return objs
	}
	if library.buildStubs() {
		return library.compileModuleLibApiStubs(ctx, flags, deps)
	}

	srcs := library.baseCompiler.Properties.Srcs.GetOrDefault(ctx, nil)
	staticSrcs := library.StaticProperties.Static.Srcs.GetOrDefault(ctx, nil)
	sharedSrcs := library.SharedProperties.Shared.Srcs.GetOrDefault(ctx, nil)
	if !library.buildShared() && !library.buildStatic() {
		if len(srcs) > 0 {
			ctx.PropertyErrorf("srcs", "cc_library_headers must not have any srcs")
		}
		if len(staticSrcs) > 0 {
			ctx.PropertyErrorf("static.srcs", "cc_library_headers must not have any srcs")
		}
		if len(sharedSrcs) > 0 {
			ctx.PropertyErrorf("shared.srcs", "cc_library_headers must not have any srcs")
		}
		return Objects{}
	}
	if library.sabi.shouldCreateSourceAbiDump() {
		dirs := library.exportedIncludeDirsForAbiCheck(ctx)
		flags.SAbiFlags = make([]string, 0, len(dirs))
		for _, dir := range dirs {
			flags.SAbiFlags = append(flags.SAbiFlags, "-I"+dir)
		}
		totalLength := len(srcs) + len(deps.GeneratedSources) +
			len(sharedSrcs) + len(staticSrcs)
		if totalLength > 0 {
			flags.SAbiDump = true
		}
	}
	objs := library.baseCompiler.compile(ctx, flags, deps)
	library.reuseObjects = objs
	buildFlags := flagsToBuilderFlags(flags)

	if library.static() {
		srcs := android.PathsForModuleSrc(ctx, staticSrcs)
		objs = objs.Append(compileObjs(ctx, buildFlags, android.DeviceStaticLibrary, srcs,
			android.PathsForModuleSrc(ctx, library.StaticProperties.Static.Tidy_disabled_srcs),
			android.PathsForModuleSrc(ctx, library.StaticProperties.Static.Tidy_timeout_srcs),
			library.baseCompiler.pathDeps, library.baseCompiler.cFlagsDeps))
	} else if library.shared() {
		srcs := android.PathsForModuleSrc(ctx, sharedSrcs)
		objs = objs.Append(compileObjs(ctx, buildFlags, android.DeviceSharedLibrary, srcs,
			android.PathsForModuleSrc(ctx, library.SharedProperties.Shared.Tidy_disabled_srcs),
			android.PathsForModuleSrc(ctx, library.SharedProperties.Shared.Tidy_timeout_srcs),
			library.baseCompiler.pathDeps, library.baseCompiler.cFlagsDeps))
	}

	return objs
}

// Compile stubs for the API surface between platform and apex
// This method will be used by source and prebuilt cc module types.
func (library *libraryDecorator) compileModuleLibApiStubs(ctx ModuleContext, flags Flags, deps PathDeps) Objects {
	// TODO (b/275273834): Make this a hard error when the symbol files have been added to module sdk.
	if library.Properties.Stubs.Symbol_file == nil {
		return Objects{}
	}
	symbolFile := String(library.Properties.Stubs.Symbol_file)
	library.stubsSymbolFilePath = android.PathForModuleSrc(ctx, symbolFile)
	// b/239274367 --apex and --systemapi filters symbols tagged with # apex and #
	// systemapi, respectively. The former is for symbols defined in platform libraries
	// and the latter is for symbols defined in APEXes.
	// A single library can contain either # apex or # systemapi, but not both.
	// The stub generator (ndkstubgen) is additive, so passing _both_ of these to it should be a no-op.
	// However, having this distinction helps guard accidental
	// promotion or demotion of API and also helps the API review process b/191371676
	var flag string
	if ctx.Module().(android.ApexModule).NotInPlatform() {
		flag = "--apex"
	} else {
		flag = "--systemapi"
	}
	// b/184712170, unless the lib is an NDK library, exclude all public symbols from
	// the stub so that it is mandated that all symbols are explicitly marked with
	// either apex or systemapi.
	if !ctx.Module().(*Module).IsNdk(ctx.Config()) &&
		// the symbol files of libclang libs are autogenerated and do not contain systemapi tags
		// TODO (spandandas): Update mapfile.py to include #systemapi tag on all symbols
		!strings.Contains(ctx.ModuleName(), "libclang_rt") {
		flag = flag + " --no-ndk"
	}
	// TODO(b/361303067): Remove this special case if bionic/ projects are added to ART development branches.
	if isBionic(ctx.baseModuleName()) {
		// set the flags explicitly for bionic libs.
		// this is necessary for development in minimal branches which does not contain bionic/*.
		// In such minimal branches, e.g. on the prebuilt libc stubs
		// 1. IsNdk will return false (since the ndk_library definition for libc does not exist)
		// 2. NotInPlatform will return true (since the source com.android.runtime does not exist)
		flag = "--apex"
	}
	nativeAbiResult := parseNativeAbiDefinition(ctx, symbolFile,
		android.ApiLevelOrPanic(ctx, library.MutatedProperties.StubsVersion), flag)
	objs := compileStubLibrary(ctx, flags, nativeAbiResult.stubSrc)

	library.versionScriptPath = android.OptionalPathForPath(
		nativeAbiResult.versionScript)

	// Parse symbol file to get API list for coverage
	if library.stubsVersion() == "current" && ctx.PrimaryArch() && !ctx.inRecovery() && !ctx.inProduct() && !ctx.inVendor() {
		library.apiListCoverageXmlPath = parseSymbolFileForAPICoverage(ctx, symbolFile)
	}

	return objs
}

type libraryInterface interface {
	versionedInterface

	static() bool
	shared() bool
	objs() Objects
	reuseObjs() Objects
	toc() android.OptionalPath

	// Returns true if the build options for the module have selected a static or shared build
	buildStatic() bool
	buildShared() bool

	// Sets whether a specific variant is static or shared
	setStatic()
	setShared()

	// Gets the ABI properties for vendor, product, or platform variant
	getHeaderAbiCheckerProperties(ctx android.BaseModuleContext) headerAbiCheckerProperties

	// Write LOCAL_ADDITIONAL_DEPENDENCIES for ABI diff
	androidMkWriteAdditionalDependenciesForSourceAbiDiff(w io.Writer)

	availableFor(string) bool

	getAPIListCoverageXMLPath() android.ModuleOutPath

	installable() *bool
}

type versionedInterface interface {
	buildStubs() bool
	setBuildStubs(isLatest bool)
	hasStubsVariants() bool
	isStubsImplementationRequired() bool
	setStubsVersion(string)
	stubsVersion() string

	stubsVersions(ctx android.BaseModuleContext) []string
	setAllStubsVersions([]string)
	allStubsVersions() []string

	implementationModuleName(name string) string
	hasLLNDKStubs() bool
	hasLLNDKHeaders() bool
	hasVendorPublicLibrary() bool
}

var _ libraryInterface = (*libraryDecorator)(nil)
var _ versionedInterface = (*libraryDecorator)(nil)

func (library *libraryDecorator) getLibNameHelper(baseModuleName string, inVendor bool, inProduct bool) string {
	name := library.libName
	if name == "" {
		name = String(library.Properties.Stem)
		if name == "" {
			name = baseModuleName
		}
	}

	suffix := ""
	if inVendor {
		suffix = String(library.Properties.Target.Vendor.Suffix)
	} else if inProduct {
		suffix = String(library.Properties.Target.Product.Suffix)
	}
	if suffix == "" {
		suffix = String(library.Properties.Suffix)
	}

	return name + suffix
}

// getLibName returns the actual canonical name of the library (the name which
// should be passed to the linker via linker flags).
func (library *libraryDecorator) getLibName(ctx BaseModuleContext) string {
	name := library.getLibNameHelper(ctx.baseModuleName(), ctx.inVendor(), ctx.inProduct())

	if ctx.Host() && Bool(library.Properties.Unique_host_soname) {
		if !strings.HasSuffix(name, "-host") {
			name = name + "-host"
		}
	}

	return name
}

var versioningMacroNamesListMutex sync.Mutex

func (library *libraryDecorator) linkerInit(ctx BaseModuleContext) {
	location := InstallInSystem
	if library.baseLinker.sanitize.inSanitizerDir() {
		location = InstallInSanitizerDir
	}
	library.baseInstaller.location = location
	library.baseLinker.linkerInit(ctx)
	// Let baseLinker know whether this variant is for stubs or not, so that
	// it can omit things that are not required for linking stubs.
	library.baseLinker.dynamicProperties.BuildStubs = library.buildStubs()

	if library.buildStubs() {
		macroNames := versioningMacroNamesList(ctx.Config())
		myName := versioningMacroName(ctx.ModuleName())
		versioningMacroNamesListMutex.Lock()
		defer versioningMacroNamesListMutex.Unlock()
		if (*macroNames)[myName] == "" {
			(*macroNames)[myName] = ctx.ModuleName()
		} else if (*macroNames)[myName] != ctx.ModuleName() {
			ctx.ModuleErrorf("Macro name %q for versioning conflicts with macro name from module %q ", myName, (*macroNames)[myName])
		}
	}
}

func (library *libraryDecorator) compilerDeps(ctx DepsContext, deps Deps) Deps {
	if ctx.IsLlndk() {
		// LLNDK libraries ignore most of the properties on the cc_library and use the
		// LLNDK-specific properties instead.
		return deps
	}

	deps = library.baseCompiler.compilerDeps(ctx, deps)

	return deps
}

func (library *libraryDecorator) linkerDeps(ctx DepsContext, deps Deps) Deps {
	if ctx.IsLlndk() {
		// LLNDK libraries ignore most of the properties on the cc_library and use the
		// LLNDK-specific properties instead.
		deps.HeaderLibs = append([]string(nil), library.Properties.Llndk.Export_llndk_headers...)
		deps.ReexportHeaderLibHeaders = append([]string(nil), library.Properties.Llndk.Export_llndk_headers...)
		return deps
	}
	if ctx.IsVendorPublicLibrary() {
		headers := library.Properties.Vendor_public_library.Export_public_headers
		deps.HeaderLibs = append([]string(nil), headers...)
		deps.ReexportHeaderLibHeaders = append([]string(nil), headers...)
		return deps
	}

	if library.static() {
		// Compare with nil because an empty list needs to be propagated.
		if library.StaticProperties.Static.System_shared_libs != nil {
			library.baseLinker.Properties.System_shared_libs = library.StaticProperties.Static.System_shared_libs
		}
	} else if library.shared() {
		// Compare with nil because an empty list needs to be propagated.
		if library.SharedProperties.Shared.System_shared_libs != nil {
			library.baseLinker.Properties.System_shared_libs = library.SharedProperties.Shared.System_shared_libs
		}
	}

	deps = library.baseLinker.linkerDeps(ctx, deps)

	if library.static() {
		deps.WholeStaticLibs = append(deps.WholeStaticLibs,
			library.StaticProperties.Static.Whole_static_libs.GetOrDefault(ctx, nil)...)
		deps.StaticLibs = append(deps.StaticLibs, library.StaticProperties.Static.Static_libs.GetOrDefault(ctx, nil)...)
		deps.SharedLibs = append(deps.SharedLibs, library.StaticProperties.Static.Shared_libs.GetOrDefault(ctx, nil)...)

		deps.ReexportSharedLibHeaders = append(deps.ReexportSharedLibHeaders, library.StaticProperties.Static.Export_shared_lib_headers...)
		deps.ReexportStaticLibHeaders = append(deps.ReexportStaticLibHeaders, library.StaticProperties.Static.Export_static_lib_headers...)
	} else if library.shared() {
		if library.baseLinker.Properties.crt() {
			deps.CrtBegin = append(deps.CrtBegin, ctx.toolchain().CrtBeginSharedLibrary()...)
			deps.CrtEnd = append(deps.CrtEnd, ctx.toolchain().CrtEndSharedLibrary()...)

		}
		if library.baseLinker.Properties.crtPadSegment() {
			deps.CrtEnd = append(deps.CrtEnd, ctx.toolchain().CrtPadSegmentSharedLibrary()...)
		}
		deps.WholeStaticLibs = append(deps.WholeStaticLibs, library.SharedProperties.Shared.Whole_static_libs.GetOrDefault(ctx, nil)...)
		deps.StaticLibs = append(deps.StaticLibs, library.SharedProperties.Shared.Static_libs.GetOrDefault(ctx, nil)...)
		deps.SharedLibs = append(deps.SharedLibs, library.SharedProperties.Shared.Shared_libs.GetOrDefault(ctx, nil)...)

		deps.ReexportSharedLibHeaders = append(deps.ReexportSharedLibHeaders, library.SharedProperties.Shared.Export_shared_lib_headers...)
		deps.ReexportStaticLibHeaders = append(deps.ReexportStaticLibHeaders, library.SharedProperties.Shared.Export_static_lib_headers...)

		deps.LlndkHeaderLibs = append(deps.LlndkHeaderLibs, library.Properties.Llndk.Export_llndk_headers...)
	}
	if ctx.inVendor() {
		deps.WholeStaticLibs = removeListFromList(deps.WholeStaticLibs, library.baseLinker.Properties.Target.Vendor.Exclude_static_libs)
		deps.SharedLibs = removeListFromList(deps.SharedLibs, library.baseLinker.Properties.Target.Vendor.Exclude_shared_libs)
		deps.StaticLibs = removeListFromList(deps.StaticLibs, library.baseLinker.Properties.Target.Vendor.Exclude_static_libs)
		deps.ReexportSharedLibHeaders = removeListFromList(deps.ReexportSharedLibHeaders, library.baseLinker.Properties.Target.Vendor.Exclude_shared_libs)
		deps.ReexportStaticLibHeaders = removeListFromList(deps.ReexportStaticLibHeaders, library.baseLinker.Properties.Target.Vendor.Exclude_static_libs)
	}
	if ctx.inProduct() {
		deps.WholeStaticLibs = removeListFromList(deps.WholeStaticLibs, library.baseLinker.Properties.Target.Product.Exclude_static_libs)
		deps.SharedLibs = removeListFromList(deps.SharedLibs, library.baseLinker.Properties.Target.Product.Exclude_shared_libs)
		deps.StaticLibs = removeListFromList(deps.StaticLibs, library.baseLinker.Properties.Target.Product.Exclude_static_libs)
		deps.ReexportSharedLibHeaders = removeListFromList(deps.ReexportSharedLibHeaders, library.baseLinker.Properties.Target.Product.Exclude_shared_libs)
		deps.ReexportStaticLibHeaders = removeListFromList(deps.ReexportStaticLibHeaders, library.baseLinker.Properties.Target.Product.Exclude_static_libs)
	}
	if ctx.inRecovery() {
		deps.WholeStaticLibs = removeListFromList(deps.WholeStaticLibs, library.baseLinker.Properties.Target.Recovery.Exclude_static_libs)
		deps.SharedLibs = removeListFromList(deps.SharedLibs, library.baseLinker.Properties.Target.Recovery.Exclude_shared_libs)
		deps.StaticLibs = removeListFromList(deps.StaticLibs, library.baseLinker.Properties.Target.Recovery.Exclude_static_libs)
		deps.ReexportSharedLibHeaders = removeListFromList(deps.ReexportSharedLibHeaders, library.baseLinker.Properties.Target.Recovery.Exclude_shared_libs)
		deps.ReexportStaticLibHeaders = removeListFromList(deps.ReexportStaticLibHeaders, library.baseLinker.Properties.Target.Recovery.Exclude_static_libs)
	}
	if ctx.inRamdisk() {
		deps.WholeStaticLibs = removeListFromList(deps.WholeStaticLibs, library.baseLinker.Properties.Target.Ramdisk.Exclude_static_libs)
		deps.SharedLibs = removeListFromList(deps.SharedLibs, library.baseLinker.Properties.Target.Ramdisk.Exclude_shared_libs)
		deps.StaticLibs = removeListFromList(deps.StaticLibs, library.baseLinker.Properties.Target.Ramdisk.Exclude_static_libs)
		deps.ReexportSharedLibHeaders = removeListFromList(deps.ReexportSharedLibHeaders, library.baseLinker.Properties.Target.Ramdisk.Exclude_shared_libs)
		deps.ReexportStaticLibHeaders = removeListFromList(deps.ReexportStaticLibHeaders, library.baseLinker.Properties.Target.Ramdisk.Exclude_static_libs)
	}
	if ctx.inVendorRamdisk() {
		deps.WholeStaticLibs = removeListFromList(deps.WholeStaticLibs, library.baseLinker.Properties.Target.Vendor_ramdisk.Exclude_static_libs)
		deps.SharedLibs = removeListFromList(deps.SharedLibs, library.baseLinker.Properties.Target.Vendor_ramdisk.Exclude_shared_libs)
		deps.StaticLibs = removeListFromList(deps.StaticLibs, library.baseLinker.Properties.Target.Vendor_ramdisk.Exclude_static_libs)
		deps.ReexportSharedLibHeaders = removeListFromList(deps.ReexportSharedLibHeaders, library.baseLinker.Properties.Target.Vendor_ramdisk.Exclude_shared_libs)
		deps.ReexportStaticLibHeaders = removeListFromList(deps.ReexportStaticLibHeaders, library.baseLinker.Properties.Target.Vendor_ramdisk.Exclude_static_libs)
	}

	return deps
}

func (library *libraryDecorator) linkerSpecifiedDeps(ctx android.ConfigurableEvaluatorContext, module *Module, specifiedDeps specifiedDeps) specifiedDeps {
	specifiedDeps = library.baseLinker.linkerSpecifiedDeps(ctx, module, specifiedDeps)
	var properties StaticOrSharedProperties
	if library.static() {
		properties = library.StaticProperties.Static
	} else if library.shared() {
		properties = library.SharedProperties.Shared
	}

	eval := module.ConfigurableEvaluator(ctx)
	specifiedDeps.sharedLibs = append(specifiedDeps.sharedLibs, properties.Shared_libs.GetOrDefault(eval, nil)...)

	// Must distinguish nil and [] in system_shared_libs - ensure that [] in
	// either input list doesn't come out as nil.
	if specifiedDeps.systemSharedLibs == nil {
		specifiedDeps.systemSharedLibs = properties.System_shared_libs
	} else {
		specifiedDeps.systemSharedLibs = append(specifiedDeps.systemSharedLibs, properties.System_shared_libs...)
	}

	specifiedDeps.sharedLibs = android.FirstUniqueStrings(specifiedDeps.sharedLibs)
	if len(specifiedDeps.systemSharedLibs) > 0 {
		// Skip this if systemSharedLibs is either nil or [], to ensure they are
		// retained.
		specifiedDeps.systemSharedLibs = android.FirstUniqueStrings(specifiedDeps.systemSharedLibs)
	}
	return specifiedDeps
}

func (library *libraryDecorator) moduleInfoJSON(ctx ModuleContext, moduleInfoJSON *android.ModuleInfoJSON) {
	if library.static() {
		moduleInfoJSON.Class = []string{"STATIC_LIBRARIES"}
		moduleInfoJSON.Uninstallable = true
	} else if library.shared() {
		moduleInfoJSON.Class = []string{"SHARED_LIBRARIES"}
	} else if library.header() {
		moduleInfoJSON.Class = []string{"HEADER_LIBRARIES"}
		moduleInfoJSON.Uninstallable = true
	}

	if library.buildStubs() && library.stubsVersion() != "" {
		moduleInfoJSON.SubName += "." + library.stubsVersion()
	}

	// If a library providing a stub is included in an APEX, the private APIs of the library
	// is accessible only inside the APEX. From outside of the APEX, clients can only use the
	// public APIs via the stub. To enforce this, the (latest version of the) stub gets the
	// name of the library. The impl library instead gets the `.bootstrap` suffix to so that
	// they can be exceptionally used directly when APEXes are not available (e.g. during the
	// very early stage in the boot process).
	if len(library.Properties.Stubs.Versions) > 0 && !ctx.Host() && ctx.notInPlatform() &&
		!ctx.inRamdisk() && !ctx.inVendorRamdisk() && !ctx.inRecovery() && !ctx.useVndk() && !ctx.static() {
		if library.buildStubs() && library.isLatestStubVersion() {
			moduleInfoJSON.SubName = ""
		}
		if !library.buildStubs() {
			moduleInfoJSON.SubName = ".bootstrap"
		}
	}

	library.baseLinker.moduleInfoJSON(ctx, moduleInfoJSON)
}

func (library *libraryDecorator) linkStatic(ctx ModuleContext,
	flags Flags, deps PathDeps, objs Objects) android.Path {

	library.objects = deps.WholeStaticLibObjs.Copy()
	library.objects = library.objects.Append(objs)
	library.wholeStaticLibsFromPrebuilts = android.CopyOfPaths(deps.WholeStaticLibsFromPrebuilts)

	fileName := ctx.ModuleName() + staticLibraryExtension
	outputFile := android.PathForModuleOut(ctx, fileName)
	builderFlags := flagsToBuilderFlags(flags)

	if Bool(library.baseLinker.Properties.Use_version_lib) {
		if ctx.Host() {
			versionedOutputFile := outputFile
			outputFile = android.PathForModuleOut(ctx, "unversioned", fileName)
			library.injectVersionSymbol(ctx, outputFile, versionedOutputFile)
		} else {
			versionedOutputFile := android.PathForModuleOut(ctx, "versioned", fileName)
			library.distFile = versionedOutputFile
			library.injectVersionSymbol(ctx, outputFile, versionedOutputFile)
		}
	}

	transformObjToStaticLib(ctx, library.objects.objFiles, deps.WholeStaticLibsFromPrebuilts, builderFlags, outputFile, nil, objs.tidyDepFiles)

	library.coverageOutputFile = transformCoverageFilesToZip(ctx, library.objects, ctx.ModuleName())

	ctx.CheckbuildFile(outputFile)

	if library.static() {
		android.SetProvider(ctx, StaticLibraryInfoProvider, StaticLibraryInfo{
			StaticLibrary:                outputFile,
			ReuseObjects:                 library.reuseObjects,
			Objects:                      library.objects,
			WholeStaticLibsFromPrebuilts: library.wholeStaticLibsFromPrebuilts,

			TransitiveStaticLibrariesForOrdering: android.NewDepSetBuilder[android.Path](android.TOPOLOGICAL).
				Direct(outputFile).
				Transitive(deps.TranstiveStaticLibrariesForOrdering).
				Build(),
		})
	}

	if library.header() {
		android.SetProvider(ctx, HeaderLibraryInfoProvider, HeaderLibraryInfo{})
	}

	return outputFile
}

func ndkSharedLibDeps(ctx ModuleContext) android.Paths {
	if ctx.Module().(*Module).IsSdkVariant() {
		// The NDK sysroot timestamp file depends on all the NDK
		// sysroot header and shared library files.
		return android.Paths{getNdkBaseTimestampFile(ctx)}
	}
	return nil
}

func (library *libraryDecorator) linkShared(ctx ModuleContext,
	flags Flags, deps PathDeps, objs Objects) android.Path {

	var linkerDeps android.Paths
	linkerDeps = append(linkerDeps, flags.LdFlagsDeps...)
	linkerDeps = append(linkerDeps, ndkSharedLibDeps(ctx)...)

	unexportedSymbols := ctx.ExpandOptionalSource(library.Properties.Unexported_symbols_list, "unexported_symbols_list")
	forceNotWeakSymbols := ctx.ExpandOptionalSource(library.Properties.Force_symbols_not_weak_list, "force_symbols_not_weak_list")
	forceWeakSymbols := ctx.ExpandOptionalSource(library.Properties.Force_symbols_weak_list, "force_symbols_weak_list")
	if !ctx.Darwin() {
		if unexportedSymbols.Valid() {
			ctx.PropertyErrorf("unexported_symbols_list", "Only supported on Darwin")
		}
		if forceNotWeakSymbols.Valid() {
			ctx.PropertyErrorf("force_symbols_not_weak_list", "Only supported on Darwin")
		}
		if forceWeakSymbols.Valid() {
			ctx.PropertyErrorf("force_symbols_weak_list", "Only supported on Darwin")
		}
	} else {
		if unexportedSymbols.Valid() {
			flags.Local.LdFlags = append(flags.Local.LdFlags, "-Wl,-unexported_symbols_list,"+unexportedSymbols.String())
			linkerDeps = append(linkerDeps, unexportedSymbols.Path())
		}
		if forceNotWeakSymbols.Valid() {
			flags.Local.LdFlags = append(flags.Local.LdFlags, "-Wl,-force_symbols_not_weak_list,"+forceNotWeakSymbols.String())
			linkerDeps = append(linkerDeps, forceNotWeakSymbols.Path())
		}
		if forceWeakSymbols.Valid() {
			flags.Local.LdFlags = append(flags.Local.LdFlags, "-Wl,-force_symbols_weak_list,"+forceWeakSymbols.String())
			linkerDeps = append(linkerDeps, forceWeakSymbols.Path())
		}
	}
	if library.versionScriptPath.Valid() {
		linkerScriptFlags := "-Wl,--version-script," + library.versionScriptPath.String()
		flags.Local.LdFlags = append(flags.Local.LdFlags, linkerScriptFlags)
		linkerDeps = append(linkerDeps, library.versionScriptPath.Path())
	}

	fileName := library.getLibName(ctx) + flags.Toolchain.ShlibSuffix()
	outputFile := android.PathForModuleOut(ctx, fileName)
	unstrippedOutputFile := outputFile

	var implicitOutputs android.WritablePaths
	if ctx.Windows() {
		importLibraryPath := android.PathForModuleOut(ctx, pathtools.ReplaceExtension(fileName, "lib"))

		flags.Local.LdFlags = append(flags.Local.LdFlags, "-Wl,--out-implib="+importLibraryPath.String())
		implicitOutputs = append(implicitOutputs, importLibraryPath)
	}

	builderFlags := flagsToBuilderFlags(flags)

	if ctx.Darwin() && deps.DarwinSecondArchOutput.Valid() {
		fatOutputFile := outputFile
		outputFile = android.PathForModuleOut(ctx, "pre-fat", fileName)
		transformDarwinUniversalBinary(ctx, fatOutputFile, outputFile, deps.DarwinSecondArchOutput.Path())
	}

	// Optimize out relinking against shared libraries whose interface hasn't changed by
	// depending on a table of contents file instead of the library itself.
	tocFile := outputFile.ReplaceExtension(ctx, flags.Toolchain.ShlibSuffix()[1:]+".toc")
	library.tocFile = android.OptionalPathForPath(tocFile)
	TransformSharedObjectToToc(ctx, outputFile, tocFile)

	stripFlags := flagsToStripFlags(flags)
	needsStrip := library.stripper.NeedsStrip(ctx)
	if library.buildStubs() {
		// No need to strip stubs libraries
		needsStrip = false
	}
	if needsStrip {
		if ctx.Darwin() {
			stripFlags.StripUseGnuStrip = true
		}
		strippedOutputFile := outputFile
		outputFile = android.PathForModuleOut(ctx, "unstripped", fileName)
		library.stripper.StripExecutableOrSharedLib(ctx, outputFile, strippedOutputFile, stripFlags)
	}
	library.unstrippedOutputFile = outputFile

	outputFile = maybeInjectBoringSSLHash(ctx, outputFile, library.Properties.Inject_bssl_hash, fileName)

	if Bool(library.baseLinker.Properties.Use_version_lib) {
		if ctx.Host() {
			versionedOutputFile := outputFile
			outputFile = android.PathForModuleOut(ctx, "unversioned", fileName)
			library.injectVersionSymbol(ctx, outputFile, versionedOutputFile)
		} else {
			versionedOutputFile := android.PathForModuleOut(ctx, "versioned", fileName)
			library.distFile = versionedOutputFile

			if library.stripper.NeedsStrip(ctx) {
				out := android.PathForModuleOut(ctx, "versioned-stripped", fileName)
				library.distFile = out
				library.stripper.StripExecutableOrSharedLib(ctx, versionedOutputFile, out, stripFlags)
			}

			library.injectVersionSymbol(ctx, outputFile, versionedOutputFile)
		}
	}

	// Generate an output file for dist as if strip: "all" is set on the module.
	// Currently this is for layoutlib release process only.
	for _, dist := range ctx.Module().(*Module).Dists() {
		if dist.Tag != nil && *dist.Tag == "stripped_all" {
			strippedAllOutputFile := android.PathForModuleOut(ctx, "stripped_all", fileName)
			transformStrip(ctx, outputFile, strippedAllOutputFile, StripFlags{Toolchain: flags.Toolchain})
			library.strippedAllOutputFile = strippedAllOutputFile
			break
		}
	}

	sharedLibs := deps.EarlySharedLibs
	sharedLibs = append(sharedLibs, deps.SharedLibs...)
	sharedLibs = append(sharedLibs, deps.LateSharedLibs...)

	linkerDeps = append(linkerDeps, deps.EarlySharedLibsDeps...)
	linkerDeps = append(linkerDeps, deps.SharedLibsDeps...)
	linkerDeps = append(linkerDeps, deps.LateSharedLibsDeps...)

	if generatedLib := generateRustStaticlib(ctx, deps.RustRlibDeps); generatedLib != nil && !library.buildStubs() {
		if ctx.Module().(*Module).WholeRustStaticlib {
			deps.WholeStaticLibs = append(deps.WholeStaticLibs, generatedLib)
		} else {
			deps.StaticLibs = append(deps.StaticLibs, generatedLib)
		}
	}

	transformObjToDynamicBinary(ctx, objs.objFiles, sharedLibs,
		deps.StaticLibs, deps.LateStaticLibs, deps.WholeStaticLibs, linkerDeps, deps.CrtBegin,
		deps.CrtEnd, false, builderFlags, outputFile, implicitOutputs, objs.tidyDepFiles)

	objs.coverageFiles = append(objs.coverageFiles, deps.StaticLibObjs.coverageFiles...)
	objs.coverageFiles = append(objs.coverageFiles, deps.WholeStaticLibObjs.coverageFiles...)
	objs.sAbiDumpFiles = append(objs.sAbiDumpFiles, deps.StaticLibObjs.sAbiDumpFiles...)
	objs.sAbiDumpFiles = append(objs.sAbiDumpFiles, deps.WholeStaticLibObjs.sAbiDumpFiles...)

	library.coverageOutputFile = transformCoverageFilesToZip(ctx, objs, library.getLibName(ctx))
	library.linkSAbiDumpFiles(ctx, deps, objs, fileName, unstrippedOutputFile)

	var transitiveStaticLibrariesForOrdering *android.DepSet[android.Path]
	if static := ctx.GetDirectDepsWithTag(staticVariantTag); len(static) > 0 {
		s, _ := android.OtherModuleProvider(ctx, static[0], StaticLibraryInfoProvider)
		transitiveStaticLibrariesForOrdering = s.TransitiveStaticLibrariesForOrdering
	}

	android.SetProvider(ctx, SharedLibraryInfoProvider, SharedLibraryInfo{
		TableOfContents:                      android.OptionalPathForPath(tocFile),
		SharedLibrary:                        unstrippedOutputFile,
		TransitiveStaticLibrariesForOrdering: transitiveStaticLibrariesForOrdering,
		Target:                               ctx.Target(),
	})

	addStubDependencyProviders(ctx)

	return unstrippedOutputFile
}

// Visits the stub variants of the library and returns a struct containing the stub .so paths
func addStubDependencyProviders(ctx ModuleContext) []SharedStubLibrary {
	stubsInfo := []SharedStubLibrary{}
	stubs := ctx.GetDirectDepsWithTag(stubImplDepTag)
	if len(stubs) > 0 {
		for _, stub := range stubs {
			stubInfo, ok := android.OtherModuleProvider(ctx, stub, SharedLibraryInfoProvider)
			// TODO (b/275273834): Make this a hard error when the symbol files have been added to module sdk.
			if !ok {
				continue
			}
			flagInfo, _ := android.OtherModuleProvider(ctx, stub, FlagExporterInfoProvider)
			stubsInfo = append(stubsInfo, SharedStubLibrary{
				Version:           moduleLibraryInterface(stub).stubsVersion(),
				SharedLibraryInfo: stubInfo,
				FlagExporterInfo:  flagInfo,
			})
		}
		if len(stubsInfo) > 0 {
			android.SetProvider(ctx, SharedLibraryStubsProvider, SharedLibraryStubsInfo{
				SharedStubLibraries: stubsInfo,
				IsLLNDK:             ctx.IsLlndk(),
			})
		}
	}
	return stubsInfo
}

func (library *libraryDecorator) unstrippedOutputFilePath() android.Path {
	return library.unstrippedOutputFile
}

func (library *libraryDecorator) strippedAllOutputFilePath() android.Path {
	return library.strippedAllOutputFile
}

func (library *libraryDecorator) disableStripping() {
	library.stripper.StripProperties.Strip.None = BoolPtr(true)
}

func (library *libraryDecorator) nativeCoverage() bool {
	if library.header() || library.buildStubs() {
		return false
	}
	return true
}

func (library *libraryDecorator) coverageOutputFilePath() android.OptionalPath {
	return library.coverageOutputFile
}

func (library *libraryDecorator) exportedIncludeDirsForAbiCheck(ctx ModuleContext) []string {
	exportIncludeDirs := library.flagExporter.exportedIncludes(ctx).Strings()
	exportIncludeDirs = append(exportIncludeDirs, library.sabi.Properties.ReexportedIncludes...)
	exportSystemIncludeDirs := library.flagExporter.exportedSystemIncludes(ctx).Strings()
	exportSystemIncludeDirs = append(exportSystemIncludeDirs, library.sabi.Properties.ReexportedSystemIncludes...)
	// The ABI checker does not distinguish normal and system headers.
	return append(exportIncludeDirs, exportSystemIncludeDirs...)
}

func (library *libraryDecorator) llndkIncludeDirsForAbiCheck(ctx ModuleContext, deps PathDeps) []string {
	var includeDirs, systemIncludeDirs []string

	if library.Properties.Llndk.Override_export_include_dirs != nil {
		includeDirs = append(includeDirs, android.PathsForModuleSrc(
			ctx, library.Properties.Llndk.Override_export_include_dirs).Strings()...)
	} else {
		includeDirs = append(includeDirs, library.flagExporter.exportedIncludes(ctx).Strings()...)
		// Ignore library.sabi.Properties.ReexportedIncludes because
		// LLNDK does not reexport the implementation's dependencies, such as export_header_libs.
	}

	systemIncludeDirs = append(systemIncludeDirs,
		library.flagExporter.exportedSystemIncludes(ctx).Strings()...)
	if Bool(library.Properties.Llndk.Export_headers_as_system) {
		systemIncludeDirs = append(systemIncludeDirs, includeDirs...)
		includeDirs = nil
	}
	// Header libs.
	includeDirs = append(includeDirs, deps.LlndkIncludeDirs.Strings()...)
	systemIncludeDirs = append(systemIncludeDirs, deps.LlndkSystemIncludeDirs.Strings()...)
	// The ABI checker does not distinguish normal and system headers.
	return append(includeDirs, systemIncludeDirs...)
}

func (library *libraryDecorator) linkLlndkSAbiDumpFiles(ctx ModuleContext,
	deps PathDeps, sAbiDumpFiles android.Paths, soFile android.Path, libFileName string,
	excludeSymbolVersions, excludeSymbolTags []string,
	vendorApiLevel string) android.Path {
	// NDK symbols in version 34 are LLNDK symbols. Those in version 35 are not.
	return transformDumpToLinkedDump(ctx,
		sAbiDumpFiles, soFile, libFileName+".llndk",
		library.llndkIncludeDirsForAbiCheck(ctx, deps),
		android.OptionalPathForModuleSrc(ctx, library.Properties.Llndk.Symbol_file),
		append([]string{"*_PLATFORM", "*_PRIVATE"}, excludeSymbolVersions...),
		append([]string{"platform-only"}, excludeSymbolTags...),
		[]string{"llndk=" + vendorApiLevel}, "34", true /* isLlndk */)
}

func (library *libraryDecorator) linkApexSAbiDumpFiles(ctx ModuleContext,
	deps PathDeps, sAbiDumpFiles android.Paths, soFile android.Path, libFileName string,
	excludeSymbolVersions, excludeSymbolTags []string,
	sdkVersion string) android.Path {
	return transformDumpToLinkedDump(ctx,
		sAbiDumpFiles, soFile, libFileName+".apex",
		library.exportedIncludeDirsForAbiCheck(ctx),
		android.OptionalPathForModuleSrc(ctx, library.Properties.Stubs.Symbol_file),
		append([]string{"*_PLATFORM", "*_PRIVATE"}, excludeSymbolVersions...),
		append([]string{"platform-only"}, excludeSymbolTags...),
		[]string{"apex", "systemapi"}, sdkVersion, false /* isLlndk */)
}

func getRefAbiDumpFile(ctx android.ModuleInstallPathContext,
	versionedDumpDir, fileName string) android.OptionalPath {

	currentArchType := ctx.Arch().ArchType
	primaryArchType := ctx.Config().DevicePrimaryArchType()
	archName := currentArchType.String()
	if currentArchType != primaryArchType {
		archName += "_" + primaryArchType.String()
	}

	return android.ExistentPathForSource(ctx, versionedDumpDir, archName, "source-based",
		fileName+".lsdump")
}

// Return the previous and current SDK versions for cross-version ABI diff.
func crossVersionAbiDiffSdkVersions(ctx ModuleContext, dumpDir string) (int, int) {
	sdkVersionInt := ctx.Config().PlatformSdkVersion().FinalInt()

	if ctx.Config().PlatformSdkFinal() {
		return sdkVersionInt - 1, sdkVersionInt
	} else {
		// The platform SDK version can be upgraded before finalization while the corresponding abi dumps hasn't
		// been generated. Thus the Cross-Version Check chooses PLATFORM_SDK_VERION - 1 as previous version.
		// This situation could be identified by checking the existence of the PLATFORM_SDK_VERION dump directory.
		versionedDumpDir := android.ExistentPathForSource(ctx,
			dumpDir, ctx.Config().PlatformSdkVersion().String())
		if versionedDumpDir.Valid() {
			return sdkVersionInt, sdkVersionInt + 1
		} else {
			return sdkVersionInt - 1, sdkVersionInt
		}
	}
}

// Return the SDK version for same-version ABI diff.
func currRefAbiDumpSdkVersion(ctx ModuleContext) string {
	if ctx.Config().PlatformSdkFinal() {
		// After sdk finalization, the ABI of the latest API level must be consistent with the source code,
		// so choose PLATFORM_SDK_VERSION as the current version.
		return ctx.Config().PlatformSdkVersion().String()
	} else {
		return "current"
	}
}

// sourceAbiDiff registers a build statement to compare linked sAbi dump files (.lsdump).
func (library *libraryDecorator) sourceAbiDiff(ctx android.ModuleContext,
	sourceDump, referenceDump android.Path,
	baseName, nameExt string, isLlndk, allowExtensions bool,
	sourceVersion, errorMessage string) {

	extraFlags := []string{"-target-version", sourceVersion}
	headerAbiChecker := library.getHeaderAbiCheckerProperties(ctx)
	if Bool(headerAbiChecker.Check_all_apis) {
		extraFlags = append(extraFlags, "-check-all-apis")
	} else {
		extraFlags = append(extraFlags,
			"-allow-unreferenced-changes",
			"-allow-unreferenced-elf-symbol-changes")
	}
	if isLlndk {
		extraFlags = append(extraFlags, "-consider-opaque-types-different")
	}
	if allowExtensions {
		extraFlags = append(extraFlags, "-allow-extensions")
	}
	extraFlags = append(extraFlags, headerAbiChecker.Diff_flags...)

	library.sAbiDiff = append(
		library.sAbiDiff,
		transformAbiDumpToAbiDiff(ctx, sourceDump, referenceDump,
			baseName, nameExt, extraFlags, errorMessage))
}

func (library *libraryDecorator) crossVersionAbiDiff(ctx android.ModuleContext,
	sourceDump, referenceDump android.Path,
	baseName, nameExt string, isLlndk bool, sourceVersion, prevDumpDir string) {

	errorMessage := "error: Please follow https://android.googlesource.com/platform/development/+/main/vndk/tools/header-checker/README.md#configure-cross_version-abi-check to resolve the difference between your source code and the ABI dumps in " + prevDumpDir

	library.sourceAbiDiff(ctx, sourceDump, referenceDump, baseName, nameExt,
		isLlndk, true /* allowExtensions */, sourceVersion, errorMessage)
}

func (library *libraryDecorator) sameVersionAbiDiff(ctx android.ModuleContext,
	sourceDump, referenceDump android.Path,
	baseName, nameExt string, isLlndk bool, lsdumpTagName string) {

	libName := strings.TrimSuffix(baseName, filepath.Ext(baseName))
	errorMessage := "error: Please update ABI references with: $$ANDROID_BUILD_TOP/development/vndk/tools/header-checker/utils/create_reference_dumps.py --lib " + libName + " --lib-variant " + lsdumpTagName

	targetRelease := ctx.Config().Getenv("TARGET_RELEASE")
	if targetRelease != "" {
		errorMessage += " --release " + targetRelease
	}

	library.sourceAbiDiff(ctx, sourceDump, referenceDump, baseName, nameExt,
		isLlndk, false /* allowExtensions */, "current", errorMessage)
}

func (library *libraryDecorator) optInAbiDiff(ctx android.ModuleContext,
	sourceDump, referenceDump android.Path,
	baseName, nameExt string, refDumpDir string, lsdumpTagName string) {

	libName := strings.TrimSuffix(baseName, filepath.Ext(baseName))
	errorMessage := "error: Please update ABI references with: $$ANDROID_BUILD_TOP/development/vndk/tools/header-checker/utils/create_reference_dumps.py --lib " + libName + " --lib-variant " + lsdumpTagName + " --ref-dump-dir $$ANDROID_BUILD_TOP/" + refDumpDir

	targetRelease := ctx.Config().Getenv("TARGET_RELEASE")
	if targetRelease != "" {
		errorMessage += " --release " + targetRelease
	}

	// Most opt-in libraries do not have dumps for all default architectures.
	if ctx.Config().HasDeviceProduct() {
		errorMessage += " --product " + ctx.Config().DeviceProduct()
	}

	library.sourceAbiDiff(ctx, sourceDump, referenceDump, baseName, nameExt,
		false /* isLlndk */, false /* allowExtensions */, "current", errorMessage)
}

func (library *libraryDecorator) linkSAbiDumpFiles(ctx ModuleContext, deps PathDeps, objs Objects, fileName string, soFile android.Path) {
	if library.sabi.shouldCreateSourceAbiDump() {
		exportedIncludeDirs := library.exportedIncludeDirsForAbiCheck(ctx)
		headerAbiChecker := library.getHeaderAbiCheckerProperties(ctx)
		currSdkVersion := currRefAbiDumpSdkVersion(ctx)
		currVendorVersion := ctx.Config().VendorApiLevel()

		// Generate source dumps.
		implDump := transformDumpToLinkedDump(ctx,
			objs.sAbiDumpFiles, soFile, fileName,
			exportedIncludeDirs,
			android.OptionalPathForModuleSrc(ctx, library.symbolFileForAbiCheck(ctx)),
			headerAbiChecker.Exclude_symbol_versions,
			headerAbiChecker.Exclude_symbol_tags,
			[]string{} /* includeSymbolTags */, currSdkVersion, false /* isLlndk */)

		var llndkDump, apexVariantDump android.Path
		tags := classifySourceAbiDump(ctx)
		optInTags := []lsdumpTag{}
		for _, tag := range tags {
			if tag == llndkLsdumpTag && currVendorVersion != "" {
				if llndkDump == nil {
					// TODO(b/323447559): Evaluate if replacing sAbiDumpFiles with implDump is faster
					llndkDump = library.linkLlndkSAbiDumpFiles(ctx,
						deps, objs.sAbiDumpFiles, soFile, fileName,
						headerAbiChecker.Exclude_symbol_versions,
						headerAbiChecker.Exclude_symbol_tags,
						currVendorVersion)
				}
				addLsdumpPath(string(tag) + ":" + llndkDump.String())
			} else if tag == apexLsdumpTag {
				if apexVariantDump == nil {
					apexVariantDump = library.linkApexSAbiDumpFiles(ctx,
						deps, objs.sAbiDumpFiles, soFile, fileName,
						headerAbiChecker.Exclude_symbol_versions,
						headerAbiChecker.Exclude_symbol_tags,
						currSdkVersion)
				}
				addLsdumpPath(string(tag) + ":" + apexVariantDump.String())
			} else {
				if tag.dirName() == "" {
					optInTags = append(optInTags, tag)
				}
				addLsdumpPath(string(tag) + ":" + implDump.String())
			}
		}

		// Diff source dumps and reference dumps.
		for _, tag := range tags {
			dumpDirName := tag.dirName()
			if dumpDirName == "" {
				continue
			}
			dumpDir := filepath.Join("prebuilts", "abi-dumps", dumpDirName)
			isLlndk := (tag == llndkLsdumpTag)
			isApex := (tag == apexLsdumpTag)
			binderBitness := ctx.DeviceConfig().BinderBitness()
			nameExt := ""
			if isLlndk {
				nameExt = "llndk"
			} else if isApex {
				nameExt = "apex"
			}
			// Check against the previous version.
			var prevVersion, currVersion string
			sourceDump := implDump
			// If this release config does not define VendorApiLevel, fall back to the old policy.
			if isLlndk && currVendorVersion != "" {
				prevVersion = ctx.Config().PrevVendorApiLevel()
				currVersion = currVendorVersion
				// LLNDK dumps are generated by different rules after trunk stable.
				if android.IsTrunkStableVendorApiLevel(prevVersion) {
					sourceDump = llndkDump
				}
			} else {
				prevVersionInt, currVersionInt := crossVersionAbiDiffSdkVersions(ctx, dumpDir)
				prevVersion = strconv.Itoa(prevVersionInt)
				currVersion = strconv.Itoa(currVersionInt)
				// APEX dumps are generated by different rules after trunk stable.
				if isApex && prevVersionInt > 34 {
					sourceDump = apexVariantDump
				}
			}
			prevDumpDir := filepath.Join(dumpDir, prevVersion, binderBitness)
			prevDumpFile := getRefAbiDumpFile(ctx, prevDumpDir, fileName)
			if prevDumpFile.Valid() {
				library.crossVersionAbiDiff(ctx, sourceDump, prevDumpFile.Path(),
					fileName, nameExt+prevVersion, isLlndk, currVersion, prevDumpDir)
			}
			// Check against the current version.
			sourceDump = implDump
			if isLlndk && currVendorVersion != "" {
				currVersion = currVendorVersion
				if android.IsTrunkStableVendorApiLevel(currVersion) {
					sourceDump = llndkDump
				}
			} else {
				currVersion = currSdkVersion
				if isApex && (!ctx.Config().PlatformSdkFinal() ||
					ctx.Config().PlatformSdkVersion().FinalInt() > 34) {
					sourceDump = apexVariantDump
				}
			}
			currDumpDir := filepath.Join(dumpDir, currVersion, binderBitness)
			currDumpFile := getRefAbiDumpFile(ctx, currDumpDir, fileName)
			if currDumpFile.Valid() {
				library.sameVersionAbiDiff(ctx, sourceDump, currDumpFile.Path(),
					fileName, nameExt, isLlndk, string(tag))
			}
		}

		// Assert that a module is tagged with at most one of platformLsdumpTag, productLsdumpTag, or vendorLsdumpTag.
		if len(headerAbiChecker.Ref_dump_dirs) > 0 && len(optInTags) != 1 {
			ctx.ModuleErrorf("Expect exactly one opt-in lsdump tag when ref_dump_dirs are specified: %s", optInTags)
			return
		}
		// Ensure that a module tagged with only platformLsdumpTag has ref_dump_dirs.
		// Android.bp in vendor projects should be cleaned up before this is enforced for vendorLsdumpTag and productLsdumpTag.
		if len(headerAbiChecker.Ref_dump_dirs) == 0 && len(tags) == 1 && tags[0] == platformLsdumpTag {
			ctx.ModuleErrorf("header_abi_checker is explicitly enabled, but no ref_dump_dirs are specified.")
		}
		// Check against the opt-in reference dumps.
		for i, optInDumpDir := range headerAbiChecker.Ref_dump_dirs {
			optInDumpDirPath := android.PathForModuleSrc(ctx, optInDumpDir)
			// Ref_dump_dirs are not versioned.
			// They do not contain subdir for binder bitness because 64-bit binder has been mandatory.
			optInDumpFile := getRefAbiDumpFile(ctx, optInDumpDirPath.String(), fileName)
			if !optInDumpFile.Valid() {
				continue
			}
			library.optInAbiDiff(ctx,
				implDump, optInDumpFile.Path(),
				fileName, "opt"+strconv.Itoa(i), optInDumpDirPath.String(), string(optInTags[0]))
		}
	}
}

// link registers actions to link this library, and sets various fields
// on this library to reflect information that should be exported up the build
// tree (for example, exported flags and include paths).
func (library *libraryDecorator) link(ctx ModuleContext,
	flags Flags, deps PathDeps, objs Objects) android.Path {

	if ctx.IsLlndk() {
		// override the module's export_include_dirs with llndk.override_export_include_dirs
		// if it is set.
		if override := library.Properties.Llndk.Override_export_include_dirs; override != nil {
			library.flagExporter.Properties.Export_include_dirs = proptools.NewConfigurable[[]string](
				nil,
				[]proptools.ConfigurableCase[[]string]{
					proptools.NewConfigurableCase[[]string](nil, &override),
				},
			)
		}

		if Bool(library.Properties.Llndk.Export_headers_as_system) {
			library.flagExporter.Properties.Export_system_include_dirs = append(
				library.flagExporter.Properties.Export_system_include_dirs,
				library.flagExporter.Properties.Export_include_dirs.GetOrDefault(ctx, nil)...)
			library.flagExporter.Properties.Export_include_dirs = proptools.NewConfigurable[[]string](nil, nil)
		}
	}

	if ctx.IsVendorPublicLibrary() {
		// override the module's export_include_dirs with vendor_public_library.override_export_include_dirs
		// if it is set.
		if override := library.Properties.Vendor_public_library.Override_export_include_dirs; override != nil {
			library.flagExporter.Properties.Export_include_dirs = proptools.NewConfigurable[[]string](
				nil,
				[]proptools.ConfigurableCase[[]string]{
					proptools.NewConfigurableCase[[]string](nil, &override),
				},
			)
		}
	}

	// Linking this library consists of linking `deps.Objs` (.o files in dependencies
	// of this library), together with `objs` (.o files created by compiling this
	// library).
	objs = deps.Objs.Copy().Append(objs)
	var out android.Path
	if library.static() || library.header() {
		out = library.linkStatic(ctx, flags, deps, objs)
	} else {
		out = library.linkShared(ctx, flags, deps, objs)
	}

	// Export include paths and flags to be propagated up the tree.
	library.exportIncludes(ctx)
	library.exportExtraFlags(ctx)
	library.reexportDirs(deps.ReexportedDirs...)
	library.reexportSystemDirs(deps.ReexportedSystemDirs...)
	library.reexportFlags(deps.ReexportedFlags...)
	library.reexportDeps(deps.ReexportedDeps...)
	library.addExportedGeneratedHeaders(deps.ReexportedGeneratedHeaders...)

	if library.static() && len(deps.ReexportedRustRlibDeps) > 0 {
		library.reexportRustStaticDeps(deps.ReexportedRustRlibDeps...)
	}

	// Optionally export aidl headers.
	if Bool(library.Properties.Aidl.Export_aidl_headers) {
		if library.baseCompiler.hasAidl(ctx, deps) {
			if library.baseCompiler.hasSrcExt(ctx, ".aidl") {
				dir := android.PathForModuleGen(ctx, "aidl")
				library.reexportDirs(dir)
			}
			if len(deps.AidlLibraryInfos) > 0 {
				dir := android.PathForModuleGen(ctx, "aidl_library")
				library.reexportDirs(dir)
			}

			library.reexportDeps(library.baseCompiler.aidlOrderOnlyDeps...)
			library.addExportedGeneratedHeaders(library.baseCompiler.aidlHeaders...)
		}
	}

	// Optionally export proto headers.
	if Bool(library.Properties.Proto.Export_proto_headers) {
		if library.baseCompiler.hasSrcExt(ctx, ".proto") {
			var includes android.Paths
			if flags.proto.CanonicalPathFromRoot {
				includes = append(includes, flags.proto.SubDir)
			}
			includes = append(includes, flags.proto.Dir)
			library.reexportDirs(includes...)

			library.reexportDeps(library.baseCompiler.protoOrderOnlyDeps...)
			library.addExportedGeneratedHeaders(library.baseCompiler.protoHeaders...)
		}
	}

	// If the library is sysprop_library, expose either public or internal header selectively.
	if library.baseCompiler.hasSrcExt(ctx, ".sysprop") {
		dir := android.PathForModuleGen(ctx, "sysprop", "include")
		if library.Properties.Sysprop.Platform != nil {
			isOwnerPlatform := Bool(library.Properties.Sysprop.Platform)

			// If the owner is different from the user, expose public header. That is,
			// 1) if the user is product (as owner can only be platform / vendor)
			// 2) if the owner is platform and the client is vendor
			// We don't care Platform -> Vendor dependency as it's already forbidden.
			if ctx.Device() && (ctx.ProductSpecific() || (isOwnerPlatform && ctx.inVendor())) {
				dir = android.PathForModuleGen(ctx, "sysprop/public", "include")
			}
		}

		// Make sure to only export headers which are within the include directory.
		_, headers := android.FilterPathListPredicate(library.baseCompiler.syspropHeaders, func(path android.Path) bool {
			_, isRel := android.MaybeRel(ctx, dir.String(), path.String())
			return isRel
		})

		// Add sysprop-related directories to the exported directories of this library.
		library.reexportDirs(dir)
		library.reexportDeps(library.baseCompiler.syspropOrderOnlyDeps...)
		library.addExportedGeneratedHeaders(headers...)
	}

	// Add stub-related flags if this library is a stub library.
	library.exportVersioningMacroIfNeeded(ctx)

	// Propagate a Provider containing information about exported flags, deps, and include paths.
	library.flagExporter.setProvider(ctx)

	return out
}

func (library *libraryDecorator) exportVersioningMacroIfNeeded(ctx android.BaseModuleContext) {
	if library.buildStubs() && library.stubsVersion() != "" && !library.skipAPIDefine {
		name := versioningMacroName(ctx.Module().(*Module).ImplementationModuleName(ctx))
		apiLevel, err := android.ApiLevelFromUser(ctx, library.stubsVersion())
		if err != nil {
			ctx.ModuleErrorf("Can't export version macro: %s", err.Error())
		}
		library.reexportFlags("-D" + name + "=" + strconv.Itoa(apiLevel.FinalOrPreviewInt()))
	}
}

// buildStatic returns true if this library should be built as a static library.
func (library *libraryDecorator) buildStatic() bool {
	return library.MutatedProperties.BuildStatic &&
		BoolDefault(library.StaticProperties.Static.Enabled, true)
}

// buildShared returns true if this library should be built as a shared library.
func (library *libraryDecorator) buildShared() bool {
	return library.MutatedProperties.BuildShared &&
		BoolDefault(library.SharedProperties.Shared.Enabled, true)
}

func (library *libraryDecorator) objs() Objects {
	return library.objects
}

func (library *libraryDecorator) reuseObjs() Objects {
	return library.reuseObjects
}

func (library *libraryDecorator) toc() android.OptionalPath {
	return library.tocFile
}

func (library *libraryDecorator) installSymlinkToRuntimeApex(ctx ModuleContext, file android.Path) {
	dir := library.baseInstaller.installDir(ctx)
	dirOnDevice := android.InstallPathToOnDevicePath(ctx, dir)
	// libc_hwasan has relative_install_dir set, which would mess up the dir.Base() logic.
	// hardcode here because it's the only target, if we have other targets that use this
	// we can generalise this.
	var target string
	if ctx.baseModuleName() == "libc_hwasan" {
		target = "/" + filepath.Join("apex", "com.android.runtime", "lib64", "bionic", "hwasan", file.Base())
	} else {
		base := dir.Base()
		target = "/" + filepath.Join("apex", "com.android.runtime", base, "bionic", file.Base())
	}
	ctx.InstallAbsoluteSymlink(dir, file.Base(), target)
	library.postInstallCmds = append(library.postInstallCmds, makeSymlinkCmd(dirOnDevice, file.Base(), target))
}

func (library *libraryDecorator) install(ctx ModuleContext, file android.Path) {
	if library.shared() {
		if library.hasStubsVariants() && !ctx.Host() && ctx.directlyInAnyApex() {
			// Bionic libraries (e.g. libc.so) is installed to the bootstrap subdirectory.
			// The original path becomes a symlink to the corresponding file in the
			// runtime APEX.
			translatedArch := ctx.Target().NativeBridge == android.NativeBridgeEnabled
			if InstallToBootstrap(ctx.baseModuleName(), ctx.Config()) && !library.buildStubs() &&
				!translatedArch && !ctx.inRamdisk() && !ctx.inVendorRamdisk() && !ctx.inRecovery() {
				if ctx.Device() {
					library.installSymlinkToRuntimeApex(ctx, file)
				}
				library.baseInstaller.subDir = "bootstrap"
			}
		} else if ctx.directlyInAnyApex() && ctx.IsLlndk() && !isBionic(ctx.baseModuleName()) {
			// Skip installing LLNDK (non-bionic) libraries moved to APEX.
			ctx.Module().HideFromMake()
		}

		library.baseInstaller.install(ctx, file)
	}

	if Bool(library.Properties.Static_ndk_lib) && library.static() &&
		!ctx.InVendorOrProduct() && !ctx.inRamdisk() && !ctx.inVendorRamdisk() && !ctx.inRecovery() && ctx.Device() &&
		library.baseLinker.sanitize.isUnsanitizedVariant() &&
		ctx.isForPlatform() && !ctx.isPreventInstall() {
		installPath := getUnversionedLibraryInstallPath(ctx).Join(ctx, file.Base())

		ctx.ModuleBuild(pctx, android.ModuleBuildParams{
			Rule:        android.Cp,
			Description: "install " + installPath.Base(),
			Output:      installPath,
			Input:       file,
		})

		library.ndkSysrootPath = installPath
	}
}

func (library *libraryDecorator) everInstallable() bool {
	// Only shared and static libraries are installed. Header libraries (which are
	// neither static or shared) are not installed.
	return library.shared() || library.static()
}

// static returns true if this library is for a "static' variant.
func (library *libraryDecorator) static() bool {
	return library.MutatedProperties.VariantIsStatic
}

// shared returns true if this library is for a "shared' variant.
func (library *libraryDecorator) shared() bool {
	return library.MutatedProperties.VariantIsShared
}

// header returns true if this library is for a header-only variant.
func (library *libraryDecorator) header() bool {
	// Neither "static" nor "shared" implies this library is header-only.
	return !library.static() && !library.shared()
}

// setStatic marks the library variant as "static".
func (library *libraryDecorator) setStatic() {
	library.MutatedProperties.VariantIsStatic = true
	library.MutatedProperties.VariantIsShared = false
}

// setShared marks the library variant as "shared".
func (library *libraryDecorator) setShared() {
	library.MutatedProperties.VariantIsStatic = false
	library.MutatedProperties.VariantIsShared = true
}

// BuildOnlyStatic disables building this library as a shared library.
func (library *libraryDecorator) BuildOnlyStatic() {
	library.MutatedProperties.BuildShared = false
}

// BuildOnlyShared disables building this library as a static library.
func (library *libraryDecorator) BuildOnlyShared() {
	library.MutatedProperties.BuildStatic = false
}

// HeaderOnly disables building this library as a shared or static library;
// the library only exists to propagate header file dependencies up the build graph.
func (library *libraryDecorator) HeaderOnly() {
	library.MutatedProperties.BuildShared = false
	library.MutatedProperties.BuildStatic = false
}

// hasLLNDKStubs returns true if this cc_library module has a variant that will build LLNDK stubs.
func (library *libraryDecorator) hasLLNDKStubs() bool {
	return String(library.Properties.Llndk.Symbol_file) != ""
}

// hasLLNDKStubs returns true if this cc_library module has a variant that will build LLNDK stubs.
func (library *libraryDecorator) hasLLNDKHeaders() bool {
	return Bool(library.Properties.Llndk.Llndk_headers)
}

// hasVendorPublicLibrary returns true if this cc_library module has a variant that will build
// vendor public library stubs.
func (library *libraryDecorator) hasVendorPublicLibrary() bool {
	return String(library.Properties.Vendor_public_library.Symbol_file) != ""
}

func (library *libraryDecorator) implementationModuleName(name string) string {
	return name
}

func (library *libraryDecorator) buildStubs() bool {
	return library.MutatedProperties.BuildStubs
}

func (library *libraryDecorator) symbolFileForAbiCheck(ctx ModuleContext) *string {
	if props := library.getHeaderAbiCheckerProperties(ctx); props.Symbol_file != nil {
		return props.Symbol_file
	}
	if library.hasStubsVariants() && library.Properties.Stubs.Symbol_file != nil {
		return library.Properties.Stubs.Symbol_file
	}
	// TODO(b/309880485): Distinguish platform, NDK, LLNDK, and APEX version scripts.
	if library.baseLinker.Properties.Version_script != nil {
		return library.baseLinker.Properties.Version_script
	}
	return nil
}

func (library *libraryDecorator) hasStubsVariants() bool {
	// Just having stubs.symbol_file is enough to create a stub variant. In that case
	// the stub for the future API level is created.
	return library.Properties.Stubs.Symbol_file != nil ||
		len(library.Properties.Stubs.Versions) > 0
}

func (library *libraryDecorator) isStubsImplementationRequired() bool {
	return BoolDefault(library.Properties.Stubs.Implementation_installable, true)
}

func (library *libraryDecorator) stubsVersions(ctx android.BaseModuleContext) []string {
	if !library.hasStubsVariants() {
		return nil
	}

	if library.hasLLNDKStubs() && ctx.Module().(*Module).InVendorOrProduct() {
		// LLNDK libraries only need a single stubs variant (""), which is
		// added automatically in createVersionVariations().
		return nil
	}

	// Future API level is implicitly added if there isn't
	versions := addCurrentVersionIfNotPresent(library.Properties.Stubs.Versions)
	normalizeVersions(ctx, versions)
	return versions
}

func addCurrentVersionIfNotPresent(vers []string) []string {
	if inList(android.FutureApiLevel.String(), vers) {
		return vers
	}
	// In some cases, people use the raw value "10000" in the versions property.
	// We shouldn't add the future API level in that case, otherwise there will
	// be two identical versions.
	if inList(strconv.Itoa(android.FutureApiLevel.FinalOrFutureInt()), vers) {
		return vers
	}
	return append(vers, android.FutureApiLevel.String())
}

func (library *libraryDecorator) setStubsVersion(version string) {
	library.MutatedProperties.StubsVersion = version
}

func (library *libraryDecorator) stubsVersion() string {
	return library.MutatedProperties.StubsVersion
}

func (library *libraryDecorator) setBuildStubs(isLatest bool) {
	library.MutatedProperties.BuildStubs = true
	library.MutatedProperties.IsLatestVersion = isLatest
}

func (library *libraryDecorator) setAllStubsVersions(versions []string) {
	library.MutatedProperties.AllStubsVersions = versions
}

func (library *libraryDecorator) allStubsVersions() []string {
	return library.MutatedProperties.AllStubsVersions
}

func (library *libraryDecorator) isLatestStubVersion() bool {
	return library.MutatedProperties.IsLatestVersion
}

func (library *libraryDecorator) availableFor(what string) bool {
	var list []string
	if library.static() {
		list = library.StaticProperties.Static.Apex_available
	} else if library.shared() {
		list = library.SharedProperties.Shared.Apex_available
	}
	if len(list) == 0 {
		return false
	}
	return android.CheckAvailableForApex(what, list)
}

func (library *libraryDecorator) installable() *bool {
	if library.static() {
		return library.StaticProperties.Static.Installable
	} else if library.shared() {
		return library.SharedProperties.Shared.Installable
	}
	return nil
}

func (library *libraryDecorator) makeUninstallable(mod *Module) {
	if library.static() && library.buildStatic() && !library.buildStubs() {
		// If we're asked to make a static library uninstallable we don't do
		// anything since AndroidMkEntries always sets LOCAL_UNINSTALLABLE_MODULE
		// for these entries. This is done to still get the make targets for NOTICE
		// files from notice_files.mk, which other libraries might depend on.
		return
	}
	mod.ModuleBase.MakeUninstallable()
}

func (library *libraryDecorator) getPartition() string {
	return library.path.Partition()
}

func (library *libraryDecorator) getAPIListCoverageXMLPath() android.ModuleOutPath {
	return library.apiListCoverageXmlPath
}

func (library *libraryDecorator) overriddenModules() []string {
	return library.Properties.Overrides
}

var _ overridable = (*libraryDecorator)(nil)

var versioningMacroNamesListKey = android.NewOnceKey("versioningMacroNamesList")

// versioningMacroNamesList returns a singleton map, where keys are "version macro names",
// and values are the module name responsible for registering the version macro name.
//
// Version macros are used when building against stubs, to provide version information about
// the stub. Only stub libraries should have an entry in this list.
//
// For example, when building against libFoo#ver, __LIBFOO_API__ macro is set to ver so
// that headers from libFoo can be conditionally compiled (this may hide APIs
// that are not available for the version).
//
// This map is used to ensure that there aren't conflicts between these version macro names.
func versioningMacroNamesList(config android.Config) *map[string]string {
	return config.Once(versioningMacroNamesListKey, func() interface{} {
		m := make(map[string]string)
		return &m
	}).(*map[string]string)
}

// alphanumeric and _ characters are preserved.
// other characters are all converted to _
var charsNotForMacro = regexp.MustCompile("[^a-zA-Z0-9_]+")

// versioningMacroName returns the canonical version macro name for the given module.
func versioningMacroName(moduleName string) string {
	macroName := charsNotForMacro.ReplaceAllString(moduleName, "_")
	macroName = strings.ToUpper(macroName)
	return "__" + macroName + "_API__"
}

// NewLibrary builds and returns a new Module corresponding to a C++ library.
// Individual module implementations which comprise a C++ library (or something like
// a C++ library) should call this function, set some fields on the result, and
// then call the Init function.
func NewLibrary(hod android.HostOrDeviceSupported) (*Module, *libraryDecorator) {
	module := newModule(hod, android.MultilibBoth)

	library := &libraryDecorator{
		MutatedProperties: LibraryMutatedProperties{
			BuildShared: true,
			BuildStatic: true,
		},
		baseCompiler:  NewBaseCompiler(),
		baseLinker:    NewBaseLinker(module.sanitize),
		baseInstaller: NewBaseInstaller("lib", "lib64", InstallInSystem),
		sabi:          module.sabi,
	}

	module.compiler = library
	module.linker = library
	module.installer = library
	module.library = library

	return module, library
}

// connects a shared library to a static library in order to reuse its .o files to avoid
// compiling source files twice.
func reuseStaticLibrary(ctx android.BottomUpMutatorContext, shared *Module) {
	if sharedCompiler, ok := shared.compiler.(*libraryDecorator); ok {

		// Check libraries in addition to cflags, since libraries may be exporting different
		// include directories.
		if len(sharedCompiler.StaticProperties.Static.Cflags.GetOrDefault(ctx, nil)) == 0 &&
			len(sharedCompiler.SharedProperties.Shared.Cflags.GetOrDefault(ctx, nil)) == 0 &&
			len(sharedCompiler.StaticProperties.Static.Whole_static_libs.GetOrDefault(ctx, nil)) == 0 &&
			len(sharedCompiler.SharedProperties.Shared.Whole_static_libs.GetOrDefault(ctx, nil)) == 0 &&
			len(sharedCompiler.StaticProperties.Static.Static_libs.GetOrDefault(ctx, nil)) == 0 &&
			len(sharedCompiler.SharedProperties.Shared.Static_libs.GetOrDefault(ctx, nil)) == 0 &&
			len(sharedCompiler.StaticProperties.Static.Shared_libs.GetOrDefault(ctx, nil)) == 0 &&
			len(sharedCompiler.SharedProperties.Shared.Shared_libs.GetOrDefault(ctx, nil)) == 0 &&
			// Compare System_shared_libs properties with nil because empty lists are
			// semantically significant for them.
			sharedCompiler.StaticProperties.Static.System_shared_libs == nil &&
			sharedCompiler.SharedProperties.Shared.System_shared_libs == nil {

			// TODO: namespaces?
			ctx.AddVariationDependencies([]blueprint.Variation{{"link", "static"}}, reuseObjTag, ctx.ModuleName())
			sharedCompiler.baseCompiler.Properties.OriginalSrcs =
				sharedCompiler.baseCompiler.Properties.Srcs
			sharedCompiler.baseCompiler.Properties.Srcs = proptools.NewConfigurable[[]string](nil, nil)
			sharedCompiler.baseCompiler.Properties.Generated_sources = nil
		}

		// This dep is just to reference static variant from shared variant
		ctx.AddVariationDependencies([]blueprint.Variation{{"link", "static"}}, staticVariantTag, ctx.ModuleName())
	}
}

// linkageTransitionMutator adds "static" or "shared" variants for modules depending
// on whether the module can be built as a static library or a shared library.
type linkageTransitionMutator struct{}

func (linkageTransitionMutator) Split(ctx android.BaseModuleContext) []string {
	ccPrebuilt := false
	if m, ok := ctx.Module().(*Module); ok && m.linker != nil {
		_, ccPrebuilt = m.linker.(prebuiltLibraryInterface)
	}
	if ccPrebuilt {
		library := ctx.Module().(*Module).linker.(prebuiltLibraryInterface)

		// Differentiate between header only and building an actual static/shared library
		buildStatic := library.buildStatic()
		buildShared := library.buildShared()
		if buildStatic || buildShared {
			// Always create both the static and shared variants for prebuilt libraries, and then disable the one
			// that is not being used.  This allows them to share the name of a cc_library module, which requires that
			// all the variants of the cc_library also exist on the prebuilt.
			return []string{"static", "shared"}
		} else {
			// Header only
		}
	} else if library, ok := ctx.Module().(LinkableInterface); ok && (library.CcLibraryInterface() || library.RustLibraryInterface()) {
		// Non-cc.Modules may need an empty variant for their mutators.
		variations := []string{}
		if library.NonCcVariants() {
			variations = append(variations, "")
		}
		isLLNDK := false
		if m, ok := ctx.Module().(*Module); ok {
			isLLNDK = m.IsLlndk()
		}
		buildStatic := library.BuildStaticVariant() && !isLLNDK
		buildShared := library.BuildSharedVariant()
		if buildStatic && buildShared {
			variations = append([]string{"static", "shared"}, variations...)
			return variations
		} else if buildStatic {
			variations = append([]string{"static"}, variations...)
		} else if buildShared {
			variations = append([]string{"shared"}, variations...)
		}

		if len(variations) > 0 {
			return variations
		}
	}
	return []string{""}
}

func (linkageTransitionMutator) OutgoingTransition(ctx android.OutgoingTransitionContext, sourceVariation string) string {
	return ""
}

func (linkageTransitionMutator) IncomingTransition(ctx android.IncomingTransitionContext, incomingVariation string) string {
	ccPrebuilt := false
	if m, ok := ctx.Module().(*Module); ok && m.linker != nil {
		_, ccPrebuilt = m.linker.(prebuiltLibraryInterface)
	}
	if ccPrebuilt {
		if incomingVariation != "" {
			return incomingVariation
		}
		library := ctx.Module().(*Module).linker.(prebuiltLibraryInterface)
		if library.buildShared() {
			return "shared"
		} else if library.buildStatic() {
			return "static"
		}
		return ""
	} else if library, ok := ctx.Module().(LinkableInterface); ok && library.CcLibraryInterface() {
		isLLNDK := false
		if m, ok := ctx.Module().(*Module); ok {
			isLLNDK = m.IsLlndk()
		}
		buildStatic := library.BuildStaticVariant() && !isLLNDK
		buildShared := library.BuildSharedVariant()
		if library.BuildRlibVariant() && library.IsRustFFI() && !buildStatic && (incomingVariation == "static" || incomingVariation == "") {
			// Rust modules do not build static libs, but rlibs are used as if they
			// were via `static_libs`. Thus we need to alias the BuildRlibVariant
			// to "static" for Rust FFI libraries.
			return ""
		}
		if incomingVariation != "" {
			return incomingVariation
		}
		if buildShared {
			return "shared"
		} else if buildStatic {
			return "static"
		}
		return ""
	}
	return ""
}

func (linkageTransitionMutator) Mutate(ctx android.BottomUpMutatorContext, variation string) {
	ccPrebuilt := false
	if m, ok := ctx.Module().(*Module); ok && m.linker != nil {
		_, ccPrebuilt = m.linker.(prebuiltLibraryInterface)
	}
	if ccPrebuilt {
		library := ctx.Module().(*Module).linker.(prebuiltLibraryInterface)
		if variation == "static" {
			library.setStatic()
			if !library.buildStatic() {
				library.disablePrebuilt()
			}
		} else if variation == "shared" {
			library.setShared()
			if !library.buildShared() {
				library.disablePrebuilt()
			}
		}
	} else if library, ok := ctx.Module().(LinkableInterface); ok && library.CcLibraryInterface() {
		if variation == "static" {
			library.SetStatic()
		} else if variation == "shared" {
			library.SetShared()
			var isLLNDK bool
			if m, ok := ctx.Module().(*Module); ok {
				isLLNDK = m.IsLlndk()
			}
			buildStatic := library.BuildStaticVariant() && !isLLNDK
			buildShared := library.BuildSharedVariant()
			if buildStatic && buildShared {
				if _, ok := library.(*Module); ok {
					reuseStaticLibrary(ctx, library.(*Module))
				}
			}
		}
	}
}

// normalizeVersions modifies `versions` in place, so that each raw version
// string becomes its normalized canonical form.
// Validates that the versions in `versions` are specified in least to greatest order.
func normalizeVersions(ctx android.BaseModuleContext, versions []string) {
	var previous android.ApiLevel
	for i, v := range versions {
		ver, err := android.ApiLevelFromUser(ctx, v)
		if err != nil {
			ctx.PropertyErrorf("versions", "%s", err.Error())
			return
		}
		if i > 0 && ver.LessThanOrEqualTo(previous) {
			ctx.PropertyErrorf("versions", "not sorted: %v", versions)
		}
		versions[i] = ver.String()
		previous = ver
	}
}

func perApiVersionVariations(mctx android.BaseModuleContext, minSdkVersion string) []string {
	from, err := nativeApiLevelFromUser(mctx, minSdkVersion)
	if err != nil {
		mctx.PropertyErrorf("min_sdk_version", err.Error())
		return []string{""}
	}

	return ndkLibraryVersions(mctx, from)
}

func canBeOrLinkAgainstVersionVariants(module interface {
	Host() bool
	InRamdisk() bool
	InVendorRamdisk() bool
}) bool {
	return !module.Host() && !module.InRamdisk() && !module.InVendorRamdisk()
}

func canBeVersionVariant(module interface {
	Host() bool
	InRamdisk() bool
	InVendorRamdisk() bool
	CcLibraryInterface() bool
	Shared() bool
}) bool {
	return canBeOrLinkAgainstVersionVariants(module) &&
		module.CcLibraryInterface() && module.Shared()
}

func moduleLibraryInterface(module blueprint.Module) libraryInterface {
	if m, ok := module.(*Module); ok {
		return m.library
	}
	return nil
}

// setStubsVersions normalizes the versions in the Stubs.Versions property into MutatedProperties.AllStubsVersions.
func setStubsVersions(mctx android.BaseModuleContext, library libraryInterface, module *Module) {
	if !library.buildShared() || !canBeVersionVariant(module) {
		return
	}
	versions := library.stubsVersions(mctx)
	if mctx.Failed() {
		return
	}
	// Set the versions on the pre-mutated module so they can be read by any llndk modules that
	// depend on the implementation library and haven't been mutated yet.
	library.setAllStubsVersions(versions)
}

// versionTransitionMutator splits a module into the mandatory non-stubs variant
// (which is unnamed) and zero or more stubs variants.
type versionTransitionMutator struct{}

func (versionTransitionMutator) Split(ctx android.BaseModuleContext) []string {
	if ctx.Os() != android.Android {
		return []string{""}
	}

	m, ok := ctx.Module().(*Module)
	if library := moduleLibraryInterface(ctx.Module()); library != nil && canBeVersionVariant(m) {
		setStubsVersions(ctx, library, m)

		return append(slices.Clone(library.allStubsVersions()), "")
	} else if ok && m.SplitPerApiLevel() && m.IsSdkVariant() {
		return perApiVersionVariations(ctx, m.MinSdkVersion())
	}

	return []string{""}
}

func (versionTransitionMutator) OutgoingTransition(ctx android.OutgoingTransitionContext, sourceVariation string) string {
	return ""
}

func (versionTransitionMutator) IncomingTransition(ctx android.IncomingTransitionContext, incomingVariation string) string {
	if ctx.Os() != android.Android {
		return ""
	}
	m, ok := ctx.Module().(*Module)
	if library := moduleLibraryInterface(ctx.Module()); library != nil && canBeVersionVariant(m) {
		if incomingVariation == "latest" {
			latestVersion := ""
			versions := library.allStubsVersions()
			if len(versions) > 0 {
				latestVersion = versions[len(versions)-1]
			}
			return latestVersion
		}
		return incomingVariation
	} else if ok && m.SplitPerApiLevel() && m.IsSdkVariant() {
		// If this module only has variants with versions and the incoming dependency doesn't specify which one
		// is needed then assume the latest version.
		if incomingVariation == "" {
			return android.FutureApiLevel.String()
		}
		return incomingVariation
	}

	return ""
}

func (versionTransitionMutator) Mutate(ctx android.BottomUpMutatorContext, variation string) {
	// Optimization: return early if this module can't be affected.
	if ctx.Os() != android.Android {
		return
	}

	m, ok := ctx.Module().(*Module)
	if library := moduleLibraryInterface(ctx.Module()); library != nil && canBeVersionVariant(m) {
		isLLNDK := m.IsLlndk()
		isVendorPublicLibrary := m.IsVendorPublicLibrary()

		if variation != "" || isLLNDK || isVendorPublicLibrary {
			// A stubs or LLNDK stubs variant.
			if m.sanitize != nil {
				m.sanitize.Properties.ForceDisable = true
			}
			if m.stl != nil {
				m.stl.Properties.Stl = StringPtr("none")
			}
			m.Properties.PreventInstall = true
			lib := moduleLibraryInterface(m)
			allStubsVersions := library.allStubsVersions()
			isLatest := len(allStubsVersions) > 0 && variation == allStubsVersions[len(allStubsVersions)-1]
			lib.setBuildStubs(isLatest)
		}
		if variation != "" {
			// A non-LLNDK stubs module is hidden from make
			library.setStubsVersion(variation)
			m.Properties.HideFromMake = true
		} else {
			// A non-LLNDK implementation module has a dependency to all stubs versions
			for _, version := range library.allStubsVersions() {
				ctx.AddVariationDependencies([]blueprint.Variation{{"version", version}},
					stubImplDepTag, ctx.ModuleName())
			}
		}
	} else if ok && m.SplitPerApiLevel() && m.IsSdkVariant() {
		m.Properties.Sdk_version = StringPtr(variation)
		m.Properties.Min_sdk_version = StringPtr(variation)
	}
}

// maybeInjectBoringSSLHash adds a rule to run bssl_inject_hash on the output file if the module has the
// inject_bssl_hash or if any static library dependencies have inject_bssl_hash set.  It returns the output path
// that the linked output file should be written to.
// TODO(b/137267623): Remove this in favor of a cc_genrule when they support operating on shared libraries.
func maybeInjectBoringSSLHash(ctx android.ModuleContext, outputFile android.ModuleOutPath,
	inject *bool, fileName string) android.ModuleOutPath {
	// TODO(b/137267623): Remove this in favor of a cc_genrule when they support operating on shared libraries.
	injectBoringSSLHash := Bool(inject)
	ctx.VisitDirectDeps(func(dep android.Module) {
		if tag, ok := ctx.OtherModuleDependencyTag(dep).(libraryDependencyTag); ok && tag.static() {
			if cc, ok := dep.(*Module); ok {
				if library, ok := cc.linker.(*libraryDecorator); ok {
					if Bool(library.Properties.Inject_bssl_hash) {
						injectBoringSSLHash = true
					}
				}
			}
		}
	})
	if injectBoringSSLHash {
		hashedOutputfile := outputFile
		outputFile = android.PathForModuleOut(ctx, "unhashed", fileName)

		rule := android.NewRuleBuilder(pctx, ctx)
		rule.Command().
			BuiltTool("bssl_inject_hash").
			FlagWithInput("-in-object ", outputFile).
			FlagWithOutput("-o ", hashedOutputfile)
		rule.Build("injectCryptoHash", "inject crypto hash")
	}

	return outputFile
}