cc/cmake_snapshot.go - platform/build/soong - Git at Google

 // Copyright 2024 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 (
 	"android/soong/android"
 	"bytes"
 	_ "embed"
 	"fmt"
 	"path/filepath"
 	"slices"
 	"sort"
 	"strings"
 	"text/template"

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

 const veryVerbose bool = false

 //go:embed cmake_main.txt
 var templateCmakeMainRaw string
 var templateCmakeMain *template.Template = parseTemplate(templateCmakeMainRaw)

 //go:embed cmake_module_cc.txt
 var templateCmakeModuleCcRaw string
 var templateCmakeModuleCc *template.Template = parseTemplate(templateCmakeModuleCcRaw)

 //go:embed cmake_module_aidl.txt
 var templateCmakeModuleAidlRaw string
 var templateCmakeModuleAidl *template.Template = parseTemplate(templateCmakeModuleAidlRaw)

 //go:embed cmake_ext_add_aidl_library.txt
 var cmakeExtAddAidlLibrary string

 //go:embed cmake_ext_append_flags.txt
 var cmakeExtAppendFlags string

 var defaultUnportableFlags []string = []string{
 	"-Wno-class-memaccess",
 	"-Wno-exit-time-destructors",
 	"-Wno-inconsistent-missing-override",
 	"-Wreorder-init-list",
 	"-Wno-reorder-init-list",
 	"-Wno-restrict",
 	"-Wno-stringop-overread",
 	"-Wno-subobject-linkage",
 }

 var ignoredSystemLibs []string = []string{
 	"libc++",
 	"libc++_static",
 	"prebuilt_libclang_rt.builtins",
 	"prebuilt_libclang_rt.ubsan_minimal",
 }

 // Mapping entry between Android's library name and the one used when building outside Android tree.
 type LibraryMappingProperty struct {
 	// Android library name.
 	Android_name string

 	// Library name used when building outside Android.
 	Mapped_name string

 	// If the make file is already present in Android source tree, specify its location.
 	Package_pregenerated string

 	// If the package is expected to be installed on the build host OS, specify its name.
 	Package_system string
 }

 type CmakeSnapshotProperties struct {
 	// Modules to add to the snapshot package. Their dependencies are pulled in automatically.
 	Modules []string

 	// Host prebuilts to bundle with the snapshot. These are tools needed to build outside Android.
 	Prebuilts []string

 	// Global cflags to add when building outside Android.
 	Cflags []string

 	// Flags to skip when building outside Android.
 	Cflags_ignored []string

 	// Mapping between library names used in Android tree and externally.
 	Library_mapping []LibraryMappingProperty

 	// List of cflags that are not portable between compilers that could potentially be used to
 	// build a generated package. If left empty, it's initialized with a default list.
 	Unportable_flags []string

 	// Whether to include source code as part of the snapshot package.
 	Include_sources bool
 }

 var cmakeSnapshotSourcesProvider = blueprint.NewProvider[android.Paths]()

 type CmakeSnapshot struct {
 	android.ModuleBase

 	Properties CmakeSnapshotProperties

 	zipPath android.WritablePath
 }

 type cmakeProcessedProperties struct {
 	LibraryMapping       map[string]LibraryMappingProperty
 	PregeneratedPackages []string
 	SystemPackages       []string
 }

 type cmakeSnapshotDependencyTag struct {
 	blueprint.BaseDependencyTag
 	name string
 }

 var (
 	cmakeSnapshotModuleTag   = cmakeSnapshotDependencyTag{name: "cmake-snapshot-module"}
 	cmakeSnapshotPrebuiltTag = cmakeSnapshotDependencyTag{name: "cmake-snapshot-prebuilt"}
 )

 func parseTemplate(templateContents string) *template.Template {
 	funcMap := template.FuncMap{
 		"setList": func(name string, nameSuffix string, itemPrefix string, items []string) string {
 			var list strings.Builder
 			list.WriteString("set(" + name + nameSuffix)
 			templateListBuilder(&list, itemPrefix, items)
 			return list.String()
 		},
 		"toStrings": func(files android.Paths) []string {
 			strings := make([]string, len(files))
 			for idx, file := range files {
 				strings[idx] = file.String()
 			}
 			return strings
 		},
 		"concat5": func(list1 []string, list2 []string, list3 []string, list4 []string, list5 []string) []string {
 			return append(append(append(append(list1, list2...), list3...), list4...), list5...)
 		},
 		"cflagsList": func(name string, nameSuffix string, flags []string,
 			unportableFlags []string, ignoredFlags []string) string {
 			if len(unportableFlags) == 0 {
 				unportableFlags = defaultUnportableFlags
 			}

 			var filteredPortable []string
 			var filteredUnportable []string
 			for _, flag := range flags {
 				if slices.Contains(ignoredFlags, flag) {
 					continue
 				} else if slices.Contains(unportableFlags, flag) {
 					filteredUnportable = append(filteredUnportable, flag)
 				} else {
 					filteredPortable = append(filteredPortable, flag)
 				}
 			}

 			var list strings.Builder

 			list.WriteString("set(" + name + nameSuffix)
 			templateListBuilder(&list, "", filteredPortable)

 			if len(filteredUnportable) > 0 {
 				list.WriteString("\nappend_cxx_flags_if_supported(" + name + nameSuffix)
 				templateListBuilder(&list, "", filteredUnportable)
 			}

 			return list.String()
 		},
 		"getSources": func(m *Module) android.Paths {
 			return m.compiler.(CompiledInterface).Srcs()
 		},
 		"getModuleType": getModuleType,
 		"getCompilerProperties": func(m *Module) BaseCompilerProperties {
 			return m.compiler.baseCompilerProps()
 		},
 		"getLinkerProperties": func(m *Module) BaseLinkerProperties {
 			return m.linker.baseLinkerProps()
 		},
 		"getExtraLibs":   getExtraLibs,
 		"getIncludeDirs": getIncludeDirs,
 		"mapLibraries": func(libs []string, mapping map[string]LibraryMappingProperty) []string {
 			var mappedLibs []string
 			for _, lib := range libs {
 				mappedLib, exists := mapping[lib]
 				if exists {
 					lib = mappedLib.Mapped_name
 				} else {
 					lib = "android::" + lib
 				}
 				if lib == "" {
 					continue
 				}
 				mappedLibs = append(mappedLibs, lib)
 			}
 			sort.Strings(mappedLibs)
 			mappedLibs = slices.Compact(mappedLibs)
 			return mappedLibs
 		},
 	}

 	return template.Must(template.New("").Delims("<<", ">>").Funcs(funcMap).Parse(templateContents))
 }

 func sliceWithPrefix(prefix string, slice []string) []string {
 	output := make([]string, len(slice))
 	for i, elem := range slice {
 		output[i] = prefix + elem
 	}
 	return output
 }

 func templateListBuilder(builder *strings.Builder, itemPrefix string, items []string) {
 	if len(items) > 0 {
 		builder.WriteString("\n")
 		for _, item := range items {
 			builder.WriteString("    " + itemPrefix + item + "\n")
 		}
 	}
 	builder.WriteString(")")
 }

 func executeTemplate(templ *template.Template, buffer *bytes.Buffer, data any) string {
 	buffer.Reset()
 	if err := templ.Execute(buffer, data); err != nil {
 		panic(err)
 	}
 	output := strings.TrimSpace(buffer.String())
 	buffer.Reset()
 	return output
 }

 func (m *CmakeSnapshot) DepsMutator(ctx android.BottomUpMutatorContext) {
 	variations := []blueprint.Variation{
 		{"os", "linux_glibc"},
 		{"arch", "x86_64"},
 	}
 	ctx.AddVariationDependencies(variations, cmakeSnapshotModuleTag, m.Properties.Modules...)
 	ctx.AddVariationDependencies(variations, cmakeSnapshotPrebuiltTag, m.Properties.Prebuilts...)
 }

 func (m *CmakeSnapshot) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 	var templateBuffer bytes.Buffer
 	var pprop cmakeProcessedProperties
 	m.zipPath = android.PathForModuleOut(ctx, ctx.ModuleName()+".zip")

 	// Process Library_mapping for more efficient lookups
 	pprop.LibraryMapping = map[string]LibraryMappingProperty{}
 	for _, elem := range m.Properties.Library_mapping {
 		pprop.LibraryMapping[elem.Android_name] = elem

 		if elem.Package_pregenerated != "" {
 			pprop.PregeneratedPackages = append(pprop.PregeneratedPackages, elem.Package_pregenerated)
 		}
 		sort.Strings(pprop.PregeneratedPackages)
 		pprop.PregeneratedPackages = slices.Compact(pprop.PregeneratedPackages)

 		if elem.Package_system != "" {
 			pprop.SystemPackages = append(pprop.SystemPackages, elem.Package_system)
 		}
 		sort.Strings(pprop.SystemPackages)
 		pprop.SystemPackages = slices.Compact(pprop.SystemPackages)
 	}

 	// Generating CMakeLists.txt rules for all modules in dependency tree
 	moduleDirs := map[string][]string{}
 	sourceFiles := map[string]android.Path{}
 	visitedModules := map[string]bool{}
 	var pregeneratedModules []*Module
 	ctx.WalkDeps(func(dep_a android.Module, parent android.Module) bool {
 		moduleName := ctx.OtherModuleName(dep_a)
 		dep, ok := dep_a.(*Module)
 		if !ok {
 			return false // not a cc module
 		}
 		if visited := visitedModules[moduleName]; visited {
 			return false // visit only once
 		}
 		visitedModules[moduleName] = true
 		if mapping, ok := pprop.LibraryMapping[moduleName]; ok {
 			if mapping.Package_pregenerated != "" {
 				pregeneratedModules = append(pregeneratedModules, dep)
 			}
 			return false // mapped to system or pregenerated (we'll handle these later)
 		}
 		if ctx.OtherModuleDependencyTag(dep) == cmakeSnapshotPrebuiltTag {
 			return false // we'll handle cmakeSnapshotPrebuiltTag later
 		}
 		if slices.Contains(ignoredSystemLibs, moduleName) {
 			return false // system libs built in-tree for Android
 		}
 		if dep.compiler == nil {
 			return false // unsupported module type (e.g. prebuilt)
 		}
 		isAidlModule := dep.compiler.baseCompilerProps().AidlInterface.Lang != ""

 		if !proptools.Bool(dep.Properties.Cmake_snapshot_supported) {
 			ctx.OtherModulePropertyErrorf(dep, "cmake_snapshot_supported",
 				"CMake snapshots not supported, despite being a dependency for %s",
 				ctx.OtherModuleName(parent))
 			return false
 		}

 		if veryVerbose {
 			fmt.Println("WalkDeps: " + ctx.OtherModuleName(parent) + " -> " + moduleName)
 		}

 		// Generate CMakeLists.txt fragment for this module
 		templateToUse := templateCmakeModuleCc
 		if isAidlModule {
 			templateToUse = templateCmakeModuleAidl
 		}
 		moduleFragment := executeTemplate(templateToUse, &templateBuffer, struct {
 			Ctx      *android.ModuleContext
 			M        *Module
 			Snapshot *CmakeSnapshot
 			Pprop    *cmakeProcessedProperties
 		}{
 			&ctx,
 			dep,
 			m,
 			&pprop,
 		})
 		moduleDir := ctx.OtherModuleDir(dep)
 		moduleDirs[moduleDir] = append(moduleDirs[moduleDir], moduleFragment)

 		if m.Properties.Include_sources {
 			files, _ := android.OtherModuleProvider(ctx, dep, cmakeSnapshotSourcesProvider)
 			for _, file := range files {
 				sourceFiles[file.String()] = file
 			}
 		}

 		// if it's AIDL module, no need to dive into their dependencies
 		return !isAidlModule
 	})

 	// Enumerate sources for pregenerated modules
 	if m.Properties.Include_sources {
 		for _, dep := range pregeneratedModules {
 			if !proptools.Bool(dep.Properties.Cmake_snapshot_supported) {
 				ctx.OtherModulePropertyErrorf(dep, "cmake_snapshot_supported",
 					"Pregenerated CMake snapshots not supported, despite being requested for %s",
 					ctx.ModuleName())
 				continue
 			}

 			files, _ := android.OtherModuleProvider(ctx, dep, cmakeSnapshotSourcesProvider)
 			for _, file := range files {
 				sourceFiles[file.String()] = file
 			}
 		}
 	}

 	// Merging CMakeLists.txt contents for every module directory
 	var makefilesList android.Paths
 	for moduleDir, fragments := range moduleDirs {
 		moduleCmakePath := android.PathForModuleGen(ctx, moduleDir, "CMakeLists.txt")
 		makefilesList = append(makefilesList, moduleCmakePath)
 		sort.Strings(fragments)
 		android.WriteFileRule(ctx, moduleCmakePath, strings.Join(fragments, "\n\n\n"))
 	}

 	// Generating top-level CMakeLists.txt
 	mainCmakePath := android.PathForModuleGen(ctx, "CMakeLists.txt")
 	makefilesList = append(makefilesList, mainCmakePath)
 	mainContents := executeTemplate(templateCmakeMain, &templateBuffer, struct {
 		Ctx        *android.ModuleContext
 		M          *CmakeSnapshot
 		ModuleDirs map[string][]string
 		Pprop      *cmakeProcessedProperties
 	}{
 		&ctx,
 		m,
 		moduleDirs,
 		&pprop,
 	})
 	android.WriteFileRule(ctx, mainCmakePath, mainContents)

 	// Generating CMake extensions
 	extPath := android.PathForModuleGen(ctx, "cmake", "AppendCxxFlagsIfSupported.cmake")
 	makefilesList = append(makefilesList, extPath)
 	android.WriteFileRuleVerbatim(ctx, extPath, cmakeExtAppendFlags)
 	extPath = android.PathForModuleGen(ctx, "cmake", "AddAidlLibrary.cmake")
 	makefilesList = append(makefilesList, extPath)
 	android.WriteFileRuleVerbatim(ctx, extPath, cmakeExtAddAidlLibrary)

 	// Generating the final zip file
 	zipRule := android.NewRuleBuilder(pctx, ctx)
 	zipCmd := zipRule.Command().
 		BuiltTool("soong_zip").
 		FlagWithOutput("-o ", m.zipPath)

 	// Packaging all sources into the zip file
 	if m.Properties.Include_sources {
 		var sourcesList android.Paths
 		for _, file := range sourceFiles {
 			sourcesList = append(sourcesList, file)
 		}

 		sourcesRspFile := android.PathForModuleObj(ctx, ctx.ModuleName()+"_sources.rsp")
 		zipCmd.FlagWithRspFileInputList("-r ", sourcesRspFile, sourcesList)
 	}

 	// Packaging all make files into the zip file
 	makefilesRspFile := android.PathForModuleObj(ctx, ctx.ModuleName()+"_makefiles.rsp")
 	zipCmd.
 		FlagWithArg("-C ", android.PathForModuleGen(ctx).OutputPath.String()).
 		FlagWithRspFileInputList("-r ", makefilesRspFile, makefilesList)

 	// Packaging all prebuilts into the zip file
 	if len(m.Properties.Prebuilts) > 0 {
 		var prebuiltsList android.Paths

 		ctx.VisitDirectDepsWithTag(cmakeSnapshotPrebuiltTag, func(dep android.Module) {
 			for _, file := range dep.FilesToInstall() {
 				prebuiltsList = append(prebuiltsList, file)
 			}
 		})

 		prebuiltsRspFile := android.PathForModuleObj(ctx, ctx.ModuleName()+"_prebuilts.rsp")
 		zipCmd.
 			FlagWithArg("-C ", android.PathForArbitraryOutput(ctx).String()).
 			FlagWithArg("-P ", "prebuilts").
 			FlagWithRspFileInputList("-r ", prebuiltsRspFile, prebuiltsList)
 	}

 	// Finish generating the final zip file
 	zipRule.Build(m.zipPath.String(), "archiving "+ctx.ModuleName())
 }

 func (m *CmakeSnapshot) OutputFiles(tag string) (android.Paths, error) {
 	switch tag {
 	case "":
 		return android.Paths{m.zipPath}, nil
 	default:
 		return nil, fmt.Errorf("unsupported module reference tag %q", tag)
 	}
 }

 func (m *CmakeSnapshot) AndroidMkEntries() []android.AndroidMkEntries {
 	return []android.AndroidMkEntries{{
 		Class:      "DATA",
 		OutputFile: android.OptionalPathForPath(m.zipPath),
 		ExtraEntries: []android.AndroidMkExtraEntriesFunc{
 			func(ctx android.AndroidMkExtraEntriesContext, entries *android.AndroidMkEntries) {
 				entries.SetBool("LOCAL_UNINSTALLABLE_MODULE", true)
 			},
 		},
 	}}
 }

 func getModuleType(m *Module) string {
 	switch m.linker.(type) {
 	case *binaryDecorator:
 		return "executable"
 	case *libraryDecorator:
 		return "library"
 	case *testBinary:
 		return "executable"
 	}
 	panic(fmt.Sprintf("Unexpected module type: %T", m.compiler))
 }

 func getExtraLibs(m *Module) []string {
 	switch decorator := m.linker.(type) {
 	case *testBinary:
 		if decorator.testDecorator.gtest() {
 			return []string{"libgtest"}
 		}
 	}
 	return nil
 }

 func getIncludeDirs(ctx android.ModuleContext, m *Module) []string {
 	moduleDir := ctx.OtherModuleDir(m) + string(filepath.Separator)
 	switch decorator := m.compiler.(type) {
 	case *libraryDecorator:
 		return sliceWithPrefix(moduleDir, decorator.flagExporter.Properties.Export_include_dirs)
 	}
 	return nil
 }

 // cmake_snapshot allows defining source packages for release outside of Android build tree.
 // As a result of cmake_snapshot module build, a zip file is generated with CMake build definitions
 // for selected source modules, their dependencies and optionally also the source code itself.
 func CmakeSnapshotFactory() android.Module {
 	module := &CmakeSnapshot{}
 	module.AddProperties(&module.Properties)
 	android.InitAndroidModule(module)
 	return module
 }

 func init() {
 	android.InitRegistrationContext.RegisterModuleType("cc_cmake_snapshot", CmakeSnapshotFactory)
 }
	// Copyright 2024 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 (
	"android/soong/android"
	"bytes"
	_ "embed"
	"fmt"
	"path/filepath"
	"slices"
	"sort"
	"strings"
	"text/template"

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

	const veryVerbose bool = false

	//go:embed cmake_main.txt
	var templateCmakeMainRaw string
	var templateCmakeMain *template.Template = parseTemplate(templateCmakeMainRaw)

	//go:embed cmake_module_cc.txt
	var templateCmakeModuleCcRaw string
	var templateCmakeModuleCc *template.Template = parseTemplate(templateCmakeModuleCcRaw)

	//go:embed cmake_module_aidl.txt
	var templateCmakeModuleAidlRaw string
	var templateCmakeModuleAidl *template.Template = parseTemplate(templateCmakeModuleAidlRaw)

	//go:embed cmake_ext_add_aidl_library.txt
	var cmakeExtAddAidlLibrary string

	//go:embed cmake_ext_append_flags.txt
	var cmakeExtAppendFlags string

	var defaultUnportableFlags []string = []string{
	"-Wno-class-memaccess",
	"-Wno-exit-time-destructors",
	"-Wno-inconsistent-missing-override",
	"-Wreorder-init-list",
	"-Wno-reorder-init-list",
	"-Wno-restrict",
	"-Wno-stringop-overread",
	"-Wno-subobject-linkage",
	}

	var ignoredSystemLibs []string = []string{
	"libc++",
	"libc++_static",
	"prebuilt_libclang_rt.builtins",
	"prebuilt_libclang_rt.ubsan_minimal",
	}

	// Mapping entry between Android's library name and the one used when building outside Android tree.
	type LibraryMappingProperty struct {
	// Android library name.
	Android_name string

	// Library name used when building outside Android.
	Mapped_name string

	// If the make file is already present in Android source tree, specify its location.
	Package_pregenerated string

	// If the package is expected to be installed on the build host OS, specify its name.
	Package_system string
	}

	type CmakeSnapshotProperties struct {
	// Modules to add to the snapshot package. Their dependencies are pulled in automatically.
	Modules []string

	// Host prebuilts to bundle with the snapshot. These are tools needed to build outside Android.
	Prebuilts []string

	// Global cflags to add when building outside Android.
	Cflags []string

	// Flags to skip when building outside Android.
	Cflags_ignored []string

	// Mapping between library names used in Android tree and externally.
	Library_mapping []LibraryMappingProperty

	// List of cflags that are not portable between compilers that could potentially be used to
	// build a generated package. If left empty, it's initialized with a default list.
	Unportable_flags []string

	// Whether to include source code as part of the snapshot package.
	Include_sources bool
	}

	var cmakeSnapshotSourcesProvider = blueprint.NewProvider[android.Paths]()

	type CmakeSnapshot struct {
	android.ModuleBase

	Properties CmakeSnapshotProperties

	zipPath android.WritablePath
	}

	type cmakeProcessedProperties struct {
	LibraryMapping map[string]LibraryMappingProperty
	PregeneratedPackages []string
	SystemPackages []string
	}

	type cmakeSnapshotDependencyTag struct {
	blueprint.BaseDependencyTag
	name string
	}

	var (
	cmakeSnapshotModuleTag = cmakeSnapshotDependencyTag{name: "cmake-snapshot-module"}
	cmakeSnapshotPrebuiltTag = cmakeSnapshotDependencyTag{name: "cmake-snapshot-prebuilt"}
	)

	func parseTemplate(templateContents string) *template.Template {
	funcMap := template.FuncMap{
	"setList": func(name string, nameSuffix string, itemPrefix string, items []string) string {
	var list strings.Builder
	list.WriteString("set(" + name + nameSuffix)
	templateListBuilder(&list, itemPrefix, items)
	return list.String()
	},
	"toStrings": func(files android.Paths) []string {
	strings := make([]string, len(files))
	for idx, file := range files {
	strings[idx] = file.String()
	}
	return strings
	},
	"concat5": func(list1 []string, list2 []string, list3 []string, list4 []string, list5 []string) []string {
	return append(append(append(append(list1, list2...), list3...), list4...), list5...)
	},
	"cflagsList": func(name string, nameSuffix string, flags []string,
	unportableFlags []string, ignoredFlags []string) string {
	if len(unportableFlags) == 0 {
	unportableFlags = defaultUnportableFlags
	}

	var filteredPortable []string
	var filteredUnportable []string
	for _, flag := range flags {
	if slices.Contains(ignoredFlags, flag) {
	continue
	} else if slices.Contains(unportableFlags, flag) {
	filteredUnportable = append(filteredUnportable, flag)
	} else {
	filteredPortable = append(filteredPortable, flag)
	}
	}

	var list strings.Builder

	list.WriteString("set(" + name + nameSuffix)
	templateListBuilder(&list, "", filteredPortable)

	if len(filteredUnportable) > 0 {
	list.WriteString("\nappend_cxx_flags_if_supported(" + name + nameSuffix)
	templateListBuilder(&list, "", filteredUnportable)
	}

	return list.String()
	},
	"getSources": func(m *Module) android.Paths {
	return m.compiler.(CompiledInterface).Srcs()
	},
	"getModuleType": getModuleType,
	"getCompilerProperties": func(m *Module) BaseCompilerProperties {
	return m.compiler.baseCompilerProps()
	},
	"getLinkerProperties": func(m *Module) BaseLinkerProperties {
	return m.linker.baseLinkerProps()
	},
	"getExtraLibs": getExtraLibs,
	"getIncludeDirs": getIncludeDirs,
	"mapLibraries": func(libs []string, mapping map[string]LibraryMappingProperty) []string {
	var mappedLibs []string
	for _, lib := range libs {
	mappedLib, exists := mapping[lib]
	if exists {
	lib = mappedLib.Mapped_name
	} else {
	lib = "android::" + lib
	}
	if lib == "" {
	continue
	}
	mappedLibs = append(mappedLibs, lib)
	}
	sort.Strings(mappedLibs)
	mappedLibs = slices.Compact(mappedLibs)
	return mappedLibs
	},
	}

	return template.Must(template.New("").Delims("<<", ">>").Funcs(funcMap).Parse(templateContents))
	}

	func sliceWithPrefix(prefix string, slice []string) []string {
	output := make([]string, len(slice))
	for i, elem := range slice {
	output[i] = prefix + elem
	}
	return output
	}

	func templateListBuilder(builder *strings.Builder, itemPrefix string, items []string) {
	if len(items) > 0 {
	builder.WriteString("\n")
	for _, item := range items {
	builder.WriteString(" " + itemPrefix + item + "\n")
	}
	}
	builder.WriteString(")")
	}

	func executeTemplate(templ template.Template, buffer bytes.Buffer, data any) string {
	buffer.Reset()
	if err := templ.Execute(buffer, data); err != nil {
	panic(err)
	}
	output := strings.TrimSpace(buffer.String())
	buffer.Reset()
	return output
	}

	func (m *CmakeSnapshot) DepsMutator(ctx android.BottomUpMutatorContext) {
	variations := []blueprint.Variation{
	{"os", "linux_glibc"},
	{"arch", "x86_64"},
	}
	ctx.AddVariationDependencies(variations, cmakeSnapshotModuleTag, m.Properties.Modules...)
	ctx.AddVariationDependencies(variations, cmakeSnapshotPrebuiltTag, m.Properties.Prebuilts...)
	}

	func (m *CmakeSnapshot) GenerateAndroidBuildActions(ctx android.ModuleContext) {
	var templateBuffer bytes.Buffer
	var pprop cmakeProcessedProperties
	m.zipPath = android.PathForModuleOut(ctx, ctx.ModuleName()+".zip")

	// Process Library_mapping for more efficient lookups
	pprop.LibraryMapping = map[string]LibraryMappingProperty{}
	for _, elem := range m.Properties.Library_mapping {
	pprop.LibraryMapping[elem.Android_name] = elem

	if elem.Package_pregenerated != "" {
	pprop.PregeneratedPackages = append(pprop.PregeneratedPackages, elem.Package_pregenerated)
	}
	sort.Strings(pprop.PregeneratedPackages)
	pprop.PregeneratedPackages = slices.Compact(pprop.PregeneratedPackages)

	if elem.Package_system != "" {
	pprop.SystemPackages = append(pprop.SystemPackages, elem.Package_system)
	}
	sort.Strings(pprop.SystemPackages)
	pprop.SystemPackages = slices.Compact(pprop.SystemPackages)
	}

	// Generating CMakeLists.txt rules for all modules in dependency tree
	moduleDirs := map[string][]string{}
	sourceFiles := map[string]android.Path{}
	visitedModules := map[string]bool{}
	var pregeneratedModules []*Module
	ctx.WalkDeps(func(dep_a android.Module, parent android.Module) bool {
	moduleName := ctx.OtherModuleName(dep_a)
	dep, ok := dep_a.(*Module)
	if !ok {
	return false // not a cc module
	}
	if visited := visitedModules[moduleName]; visited {
	return false // visit only once
	}
	visitedModules[moduleName] = true
	if mapping, ok := pprop.LibraryMapping[moduleName]; ok {
	if mapping.Package_pregenerated != "" {
	pregeneratedModules = append(pregeneratedModules, dep)
	}
	return false // mapped to system or pregenerated (we'll handle these later)
	}
	if ctx.OtherModuleDependencyTag(dep) == cmakeSnapshotPrebuiltTag {
	return false // we'll handle cmakeSnapshotPrebuiltTag later
	}
	if slices.Contains(ignoredSystemLibs, moduleName) {
	return false // system libs built in-tree for Android
	}
	if dep.compiler == nil {
	return false // unsupported module type (e.g. prebuilt)
	}
	isAidlModule := dep.compiler.baseCompilerProps().AidlInterface.Lang != ""

	if !proptools.Bool(dep.Properties.Cmake_snapshot_supported) {
	ctx.OtherModulePropertyErrorf(dep, "cmake_snapshot_supported",
	"CMake snapshots not supported, despite being a dependency for %s",
	ctx.OtherModuleName(parent))
	return false
	}

	if veryVerbose {
	fmt.Println("WalkDeps: " + ctx.OtherModuleName(parent) + " -> " + moduleName)
	}

	// Generate CMakeLists.txt fragment for this module
	templateToUse := templateCmakeModuleCc
	if isAidlModule {
	templateToUse = templateCmakeModuleAidl
	}
	moduleFragment := executeTemplate(templateToUse, &templateBuffer, struct {
	Ctx *android.ModuleContext
	M *Module
	Snapshot *CmakeSnapshot
	Pprop *cmakeProcessedProperties
	}{
	&ctx,
	dep,
	m,
	&pprop,
	})
	moduleDir := ctx.OtherModuleDir(dep)
	moduleDirs[moduleDir] = append(moduleDirs[moduleDir], moduleFragment)

	if m.Properties.Include_sources {
	files, _ := android.OtherModuleProvider(ctx, dep, cmakeSnapshotSourcesProvider)
	for _, file := range files {
	sourceFiles[file.String()] = file
	}
	}

	// if it's AIDL module, no need to dive into their dependencies
	return !isAidlModule
	})

	// Enumerate sources for pregenerated modules
	if m.Properties.Include_sources {
	for _, dep := range pregeneratedModules {
	if !proptools.Bool(dep.Properties.Cmake_snapshot_supported) {
	ctx.OtherModulePropertyErrorf(dep, "cmake_snapshot_supported",
	"Pregenerated CMake snapshots not supported, despite being requested for %s",
	ctx.ModuleName())
	continue
	}

	files, _ := android.OtherModuleProvider(ctx, dep, cmakeSnapshotSourcesProvider)
	for _, file := range files {
	sourceFiles[file.String()] = file
	}
	}
	}

	// Merging CMakeLists.txt contents for every module directory
	var makefilesList android.Paths
	for moduleDir, fragments := range moduleDirs {
	moduleCmakePath := android.PathForModuleGen(ctx, moduleDir, "CMakeLists.txt")
	makefilesList = append(makefilesList, moduleCmakePath)
	sort.Strings(fragments)
	android.WriteFileRule(ctx, moduleCmakePath, strings.Join(fragments, "\n\n\n"))
	}

	// Generating top-level CMakeLists.txt
	mainCmakePath := android.PathForModuleGen(ctx, "CMakeLists.txt")
	makefilesList = append(makefilesList, mainCmakePath)
	mainContents := executeTemplate(templateCmakeMain, &templateBuffer, struct {
	Ctx *android.ModuleContext
	M *CmakeSnapshot
	ModuleDirs map[string][]string
	Pprop *cmakeProcessedProperties
	}{
	&ctx,
	m,
	moduleDirs,
	&pprop,
	})
	android.WriteFileRule(ctx, mainCmakePath, mainContents)

	// Generating CMake extensions
	extPath := android.PathForModuleGen(ctx, "cmake", "AppendCxxFlagsIfSupported.cmake")
	makefilesList = append(makefilesList, extPath)
	android.WriteFileRuleVerbatim(ctx, extPath, cmakeExtAppendFlags)
	extPath = android.PathForModuleGen(ctx, "cmake", "AddAidlLibrary.cmake")
	makefilesList = append(makefilesList, extPath)
	android.WriteFileRuleVerbatim(ctx, extPath, cmakeExtAddAidlLibrary)

	// Generating the final zip file
	zipRule := android.NewRuleBuilder(pctx, ctx)
	zipCmd := zipRule.Command().
	BuiltTool("soong_zip").
	FlagWithOutput("-o ", m.zipPath)

	// Packaging all sources into the zip file
	if m.Properties.Include_sources {
	var sourcesList android.Paths
	for _, file := range sourceFiles {
	sourcesList = append(sourcesList, file)
	}

	sourcesRspFile := android.PathForModuleObj(ctx, ctx.ModuleName()+"_sources.rsp")
	zipCmd.FlagWithRspFileInputList("-r ", sourcesRspFile, sourcesList)
	}

	// Packaging all make files into the zip file
	makefilesRspFile := android.PathForModuleObj(ctx, ctx.ModuleName()+"_makefiles.rsp")
	zipCmd.
	FlagWithArg("-C ", android.PathForModuleGen(ctx).OutputPath.String()).
	FlagWithRspFileInputList("-r ", makefilesRspFile, makefilesList)

	// Packaging all prebuilts into the zip file
	if len(m.Properties.Prebuilts) > 0 {
	var prebuiltsList android.Paths

	ctx.VisitDirectDepsWithTag(cmakeSnapshotPrebuiltTag, func(dep android.Module) {
	for _, file := range dep.FilesToInstall() {
	prebuiltsList = append(prebuiltsList, file)
	}
	})

	prebuiltsRspFile := android.PathForModuleObj(ctx, ctx.ModuleName()+"_prebuilts.rsp")
	zipCmd.
	FlagWithArg("-C ", android.PathForArbitraryOutput(ctx).String()).
	FlagWithArg("-P ", "prebuilts").
	FlagWithRspFileInputList("-r ", prebuiltsRspFile, prebuiltsList)
	}

	// Finish generating the final zip file
	zipRule.Build(m.zipPath.String(), "archiving "+ctx.ModuleName())
	}

	func (m *CmakeSnapshot) OutputFiles(tag string) (android.Paths, error) {
	switch tag {
	case "":
	return android.Paths{m.zipPath}, nil
	default:
	return nil, fmt.Errorf("unsupported module reference tag %q", tag)
	}
	}

	func (m *CmakeSnapshot) AndroidMkEntries() []android.AndroidMkEntries {
	return []android.AndroidMkEntries{{
	Class: "DATA",
	OutputFile: android.OptionalPathForPath(m.zipPath),
	ExtraEntries: []android.AndroidMkExtraEntriesFunc{
	func(ctx android.AndroidMkExtraEntriesContext, entries *android.AndroidMkEntries) {
	entries.SetBool("LOCAL_UNINSTALLABLE_MODULE", true)
	},
	},
	}}
	}

	func getModuleType(m *Module) string {
	switch m.linker.(type) {
	case *binaryDecorator:
	return "executable"
	case *libraryDecorator:
	return "library"
	case *testBinary:
	return "executable"
	}
	panic(fmt.Sprintf("Unexpected module type: %T", m.compiler))
	}

	func getExtraLibs(m *Module) []string {
	switch decorator := m.linker.(type) {
	case *testBinary:
	if decorator.testDecorator.gtest() {
	return []string{"libgtest"}
	}
	}
	return nil
	}

	func getIncludeDirs(ctx android.ModuleContext, m *Module) []string {
	moduleDir := ctx.OtherModuleDir(m) + string(filepath.Separator)
	switch decorator := m.compiler.(type) {
	case *libraryDecorator:
	return sliceWithPrefix(moduleDir, decorator.flagExporter.Properties.Export_include_dirs)
	}
	return nil
	}

	// cmake_snapshot allows defining source packages for release outside of Android build tree.
	// As a result of cmake_snapshot module build, a zip file is generated with CMake build definitions
	// for selected source modules, their dependencies and optionally also the source code itself.
	func CmakeSnapshotFactory() android.Module {
	module := &CmakeSnapshot{}
	module.AddProperties(&module.Properties)
	android.InitAndroidModule(module)
	return module
	}

	func init() {
	android.InitRegistrationContext.RegisterModuleType("cc_cmake_snapshot", CmakeSnapshotFactory)
	}