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

 // Copyright 2020 The Android Open Source Project
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //      http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
 package cc

 // This file contains singletons to capture vendor and recovery snapshot. They consist of prebuilt
 // modules under AOSP so older vendor and recovery can be built with a newer system in a single
 // source tree.

 import (
 	"encoding/json"
 	"path/filepath"
 	"sort"
 	"strings"

 	"android/soong/android"
 )

 var vendorSnapshotSingleton = snapshotSingleton{
 	"vendor",
 	"SOONG_VENDOR_SNAPSHOT_ZIP",
 	android.OptionalPath{},
 	true,
 	vendorSnapshotImageSingleton,
 	false, /* fake */
 }

 var vendorFakeSnapshotSingleton = snapshotSingleton{
 	"vendor",
 	"SOONG_VENDOR_FAKE_SNAPSHOT_ZIP",
 	android.OptionalPath{},
 	true,
 	vendorSnapshotImageSingleton,
 	true, /* fake */
 }

 var recoverySnapshotSingleton = snapshotSingleton{
 	"recovery",
 	"SOONG_RECOVERY_SNAPSHOT_ZIP",
 	android.OptionalPath{},
 	false,
 	recoverySnapshotImageSingleton,
 	false, /* fake */
 }

 func VendorSnapshotSingleton() android.Singleton {
 	return &vendorSnapshotSingleton
 }

 func VendorFakeSnapshotSingleton() android.Singleton {
 	return &vendorFakeSnapshotSingleton
 }

 func RecoverySnapshotSingleton() android.Singleton {
 	return &recoverySnapshotSingleton
 }

 type snapshotSingleton struct {
 	// Name, e.g., "vendor", "recovery", "ramdisk".
 	name string

 	// Make variable that points to the snapshot file, e.g.,
 	// "SOONG_RECOVERY_SNAPSHOT_ZIP".
 	makeVar string

 	// Path to the snapshot zip file.
 	snapshotZipFile android.OptionalPath

 	// Whether the image supports VNDK extension modules.
 	supportsVndkExt bool

 	// Implementation of the image interface specific to the image
 	// associated with this snapshot (e.g., specific to the vendor image,
 	// recovery image, etc.).
 	image snapshotImage

 	// Whether this singleton is for fake snapshot or not.
 	// Fake snapshot is a snapshot whose prebuilt binaries and headers are empty.
 	// It is much faster to generate, and can be used to inspect dependencies.
 	fake bool
 }

 // Determine if a dir under source tree is an SoC-owned proprietary directory based
 // on vendor snapshot configuration
 // Examples: device/, vendor/
 func isVendorProprietaryPath(dir string, deviceConfig android.DeviceConfig) bool {
 	return VendorSnapshotSingleton().(*snapshotSingleton).image.isProprietaryPath(dir, deviceConfig)
 }

 // Determine if a dir under source tree is an SoC-owned proprietary directory based
 // on recovery snapshot configuration
 // Examples: device/, vendor/
 func isRecoveryProprietaryPath(dir string, deviceConfig android.DeviceConfig) bool {
 	return RecoverySnapshotSingleton().(*snapshotSingleton).image.isProprietaryPath(dir, deviceConfig)
 }

 func isVendorProprietaryModule(ctx android.BaseModuleContext) bool {
 	// Any module in a vendor proprietary path is a vendor proprietary
 	// module.
 	if isVendorProprietaryPath(ctx.ModuleDir(), ctx.DeviceConfig()) {
 		return true
 	}

 	// However if the module is not in a vendor proprietary path, it may
 	// still be a vendor proprietary module. This happens for cc modules
 	// that are excluded from the vendor snapshot, and it means that the
 	// vendor has assumed control of the framework-provided module.
 	if c, ok := ctx.Module().(*Module); ok {
 		if c.ExcludeFromVendorSnapshot() {
 			return true
 		}
 	}

 	return false
 }

 func isRecoveryProprietaryModule(ctx android.BaseModuleContext) bool {

 	// Any module in a recovery proprietary path is a recovery proprietary
 	// module.
 	if isRecoveryProprietaryPath(ctx.ModuleDir(), ctx.DeviceConfig()) {
 		return true
 	}

 	// However if the module is not in a recovery proprietary path, it may
 	// still be a recovery proprietary module. This happens for cc modules
 	// that are excluded from the recovery snapshot, and it means that the
 	// vendor has assumed control of the framework-provided module.

 	if c, ok := ctx.Module().(*Module); ok {
 		if c.ExcludeFromRecoverySnapshot() {
 			return true
 		}
 	}

 	return false
 }

 // Determines if the module is a candidate for snapshot.
 func isSnapshotAware(cfg android.DeviceConfig, m *Module, inProprietaryPath bool, apexInfo android.ApexInfo, image snapshotImage) bool {
 	if !m.Enabled() || m.Properties.HideFromMake {
 		return false
 	}
 	// When android/prebuilt.go selects between source and prebuilt, it sets
 	// HideFromMake on the other one to avoid duplicate install rules in make.
 	if m.IsHideFromMake() {
 		return false
 	}
 	// skip proprietary modules, but (for the vendor snapshot only)
 	// include all VNDK (static)
 	if inProprietaryPath && (!image.includeVndk() || !m.IsVndk()) {
 		return false
 	}
 	// If the module would be included based on its path, check to see if
 	// the module is marked to be excluded. If so, skip it.
 	if image.excludeFromSnapshot(m) {
 		return false
 	}
 	if m.Target().Os.Class != android.Device {
 		return false
 	}
 	if m.Target().NativeBridge == android.NativeBridgeEnabled {
 		return false
 	}
 	// the module must be installed in target image
 	if !apexInfo.IsForPlatform() || m.isSnapshotPrebuilt() || !image.inImage(m)() {
 		return false
 	}
 	// skip kernel_headers which always depend on vendor
 	if _, ok := m.linker.(*kernelHeadersDecorator); ok {
 		return false
 	}
 	// skip llndk_library and llndk_headers which are backward compatible
 	if m.IsLlndk() {
 		return false
 	}
 	if _, ok := m.linker.(*llndkStubDecorator); ok {
 		return false
 	}
 	if _, ok := m.linker.(*llndkHeadersDecorator); ok {
 		return false
 	}

 	// Libraries
 	if l, ok := m.linker.(snapshotLibraryInterface); ok {
 		if m.sanitize != nil {
 			// scs and hwasan export both sanitized and unsanitized variants for static and header
 			// Always use unsanitized variants of them.
 			for _, t := range []SanitizerType{scs, hwasan} {
 				if !l.shared() && m.sanitize.isSanitizerEnabled(t) {
 					return false
 				}
 			}
 			// cfi also exports both variants. But for static, we capture both.
 			// This is because cfi static libraries can't be linked from non-cfi modules,
 			// and vice versa. This isn't the case for scs and hwasan sanitizers.
 			if !l.static() && !l.shared() && m.sanitize.isSanitizerEnabled(cfi) {
 				return false
 			}
 		}
 		if l.static() {
 			return m.outputFile.Valid() && !image.private(m)
 		}
 		if l.shared() {
 			if !m.outputFile.Valid() {
 				return false
 			}
 			if image.includeVndk() {
 				if !m.IsVndk() {
 					return true
 				}
 				return m.IsVndkExt()
 			}
 		}
 		return true
 	}

 	// Binaries and Objects
 	if m.binary() || m.object() {
 		return m.outputFile.Valid()
 	}

 	return false
 }

 // This is to be saved as .json files, which is for development/vendor_snapshot/update.py.
 // These flags become Android.bp snapshot module properties.
 type snapshotJsonFlags struct {
 	ModuleName          string `json:",omitempty"`
 	RelativeInstallPath string `json:",omitempty"`
 	AndroidMkSuffix     string `json:",omitempty"`

 	// library flags
 	ExportedDirs       []string `json:",omitempty"`
 	ExportedSystemDirs []string `json:",omitempty"`
 	ExportedFlags      []string `json:",omitempty"`
 	Sanitize           string   `json:",omitempty"`
 	SanitizeMinimalDep bool     `json:",omitempty"`
 	SanitizeUbsanDep   bool     `json:",omitempty"`

 	// binary flags
 	Symlinks []string `json:",omitempty"`

 	// dependencies
 	SharedLibs  []string `json:",omitempty"`
 	RuntimeLibs []string `json:",omitempty"`
 	Required    []string `json:",omitempty"`

 	// extra config files
 	InitRc         []string `json:",omitempty"`
 	VintfFragments []string `json:",omitempty"`
 }

 func (c *snapshotSingleton) GenerateBuildActions(ctx android.SingletonContext) {
 	if !c.image.shouldGenerateSnapshot(ctx) {
 		return
 	}

 	var snapshotOutputs android.Paths

 	/*
 		Vendor snapshot zipped artifacts directory structure:
 		{SNAPSHOT_ARCH}/
 			arch-{TARGET_ARCH}-{TARGET_ARCH_VARIANT}/
 				shared/
 					(.so shared libraries)
 				static/
 					(.a static libraries)
 				header/
 					(header only libraries)
 				binary/
 					(executable binaries)
 				object/
 					(.o object files)
 			arch-{TARGET_2ND_ARCH}-{TARGET_2ND_ARCH_VARIANT}/
 				shared/
 					(.so shared libraries)
 				static/
 					(.a static libraries)
 				header/
 					(header only libraries)
 				binary/
 					(executable binaries)
 				object/
 					(.o object files)
 			NOTICE_FILES/
 				(notice files, e.g. libbase.txt)
 			configs/
 				(config files, e.g. init.rc files, vintf_fragments.xml files, etc.)
 			include/
 				(header files of same directory structure with source tree)
 	*/

 	snapshotDir := c.name + "-snapshot"
 	if c.fake {
 		// If this is a fake snapshot singleton, place all files under fake/ subdirectory to avoid
 		// collision with real snapshot files
 		snapshotDir = filepath.Join("fake", snapshotDir)
 	}
 	snapshotArchDir := filepath.Join(snapshotDir, ctx.DeviceConfig().DeviceArch())

 	includeDir := filepath.Join(snapshotArchDir, "include")
 	configsDir := filepath.Join(snapshotArchDir, "configs")
 	noticeDir := filepath.Join(snapshotArchDir, "NOTICE_FILES")

 	installedNotices := make(map[string]bool)
 	installedConfigs := make(map[string]bool)

 	var headers android.Paths

 	copyFile := func(ctx android.SingletonContext, path android.Path, out string, fake bool) android.OutputPath {
 		if fake {
 			// All prebuilt binaries and headers are installed by copyFile function. This makes a fake
 			// snapshot just touch prebuilts and headers, rather than installing real files.
 			return writeStringToFileRule(ctx, "", out)
 		} else {
 			return copyFileRule(ctx, path, out)
 		}
 	}

 	// installSnapshot function copies prebuilt file (.so, .a, or executable) and json flag file.
 	// For executables, init_rc and vintf_fragments files are also copied.
 	installSnapshot := func(m *Module, fake bool) android.Paths {
 		targetArch := "arch-" + m.Target().Arch.ArchType.String()
 		if m.Target().Arch.ArchVariant != "" {
 			targetArch += "-" + m.Target().Arch.ArchVariant
 		}

 		var ret android.Paths

 		prop := snapshotJsonFlags{}

 		// Common properties among snapshots.
 		prop.ModuleName = ctx.ModuleName(m)
 		if c.supportsVndkExt && m.IsVndkExt() {
 			// vndk exts are installed to /vendor/lib(64)?/vndk(-sp)?
 			if m.isVndkSp() {
 				prop.RelativeInstallPath = "vndk-sp"
 			} else {
 				prop.RelativeInstallPath = "vndk"
 			}
 		} else {
 			prop.RelativeInstallPath = m.RelativeInstallPath()
 		}
 		prop.AndroidMkSuffix = m.Properties.SubName
 		prop.RuntimeLibs = m.Properties.SnapshotRuntimeLibs
 		prop.Required = m.RequiredModuleNames()
 		for _, path := range m.InitRc() {
 			prop.InitRc = append(prop.InitRc, filepath.Join("configs", path.Base()))
 		}
 		for _, path := range m.VintfFragments() {
 			prop.VintfFragments = append(prop.VintfFragments, filepath.Join("configs", path.Base()))
 		}

 		// install config files. ignores any duplicates.
 		for _, path := range append(m.InitRc(), m.VintfFragments()...) {
 			out := filepath.Join(configsDir, path.Base())
 			if !installedConfigs[out] {
 				installedConfigs[out] = true
 				ret = append(ret, copyFile(ctx, path, out, fake))
 			}
 		}

 		var propOut string

 		if l, ok := m.linker.(snapshotLibraryInterface); ok {
 			exporterInfo := ctx.ModuleProvider(m, FlagExporterInfoProvider).(FlagExporterInfo)

 			// library flags
 			prop.ExportedFlags = exporterInfo.Flags
 			for _, dir := range exporterInfo.IncludeDirs {
 				prop.ExportedDirs = append(prop.ExportedDirs, filepath.Join("include", dir.String()))
 			}
 			for _, dir := range exporterInfo.SystemIncludeDirs {
 				prop.ExportedSystemDirs = append(prop.ExportedSystemDirs, filepath.Join("include", dir.String()))
 			}
 			// shared libs dependencies aren't meaningful on static or header libs
 			if l.shared() {
 				prop.SharedLibs = m.Properties.SnapshotSharedLibs
 			}
 			if l.static() && m.sanitize != nil {
 				prop.SanitizeMinimalDep = m.sanitize.Properties.MinimalRuntimeDep || enableMinimalRuntime(m.sanitize)
 				prop.SanitizeUbsanDep = m.sanitize.Properties.UbsanRuntimeDep || enableUbsanRuntime(m.sanitize)
 			}

 			var libType string
 			if l.static() {
 				libType = "static"
 			} else if l.shared() {
 				libType = "shared"
 			} else {
 				libType = "header"
 			}

 			var stem string

 			// install .a or .so
 			if libType != "header" {
 				libPath := m.outputFile.Path()
 				stem = libPath.Base()
 				if l.static() && m.sanitize != nil && m.sanitize.isSanitizerEnabled(cfi) {
 					// both cfi and non-cfi variant for static libraries can exist.
 					// attach .cfi to distinguish between cfi and non-cfi.
 					// e.g. libbase.a -> libbase.cfi.a
 					ext := filepath.Ext(stem)
 					stem = strings.TrimSuffix(stem, ext) + ".cfi" + ext
 					prop.Sanitize = "cfi"
 					prop.ModuleName += ".cfi"
 				}
 				snapshotLibOut := filepath.Join(snapshotArchDir, targetArch, libType, stem)
 				ret = append(ret, copyFile(ctx, libPath, snapshotLibOut, fake))
 			} else {
 				stem = ctx.ModuleName(m)
 			}

 			propOut = filepath.Join(snapshotArchDir, targetArch, libType, stem+".json")
 		} else if m.binary() {
 			// binary flags
 			prop.Symlinks = m.Symlinks()
 			prop.SharedLibs = m.Properties.SnapshotSharedLibs

 			// install bin
 			binPath := m.outputFile.Path()
 			snapshotBinOut := filepath.Join(snapshotArchDir, targetArch, "binary", binPath.Base())
 			ret = append(ret, copyFile(ctx, binPath, snapshotBinOut, fake))
 			propOut = snapshotBinOut + ".json"
 		} else if m.object() {
 			// object files aren't installed to the device, so their names can conflict.
 			// Use module name as stem.
 			objPath := m.outputFile.Path()
 			snapshotObjOut := filepath.Join(snapshotArchDir, targetArch, "object",
 				ctx.ModuleName(m)+filepath.Ext(objPath.Base()))
 			ret = append(ret, copyFile(ctx, objPath, snapshotObjOut, fake))
 			propOut = snapshotObjOut + ".json"
 		} else {
 			ctx.Errorf("unknown module %q in vendor snapshot", m.String())
 			return nil
 		}

 		j, err := json.Marshal(prop)
 		if err != nil {
 			ctx.Errorf("json marshal to %q failed: %#v", propOut, err)
 			return nil
 		}
 		ret = append(ret, writeStringToFileRule(ctx, string(j), propOut))

 		return ret
 	}

 	ctx.VisitAllModules(func(module android.Module) {
 		m, ok := module.(*Module)
 		if !ok {
 			return
 		}

 		moduleDir := ctx.ModuleDir(module)
 		inProprietaryPath := c.image.isProprietaryPath(moduleDir, ctx.DeviceConfig())
 		apexInfo := ctx.ModuleProvider(module, android.ApexInfoProvider).(android.ApexInfo)

 		if c.image.excludeFromSnapshot(m) {
 			if inProprietaryPath {
 				// Error: exclude_from_vendor_snapshot applies
 				// to framework-path modules only.
 				ctx.Errorf("module %q in vendor proprietary path %q may not use \"exclude_from_vendor_snapshot: true\"", m.String(), moduleDir)
 				return
 			}
 		}

 		if !isSnapshotAware(ctx.DeviceConfig(), m, inProprietaryPath, apexInfo, c.image) {
 			return
 		}

 		// If we are using directed snapshot and a module is not included in the
 		// list, we will still include the module as if it was a fake module.
 		// The reason is that soong needs all the dependencies to be present, even
 		// if they are not using during the build.
 		installAsFake := c.fake
 		if c.image.excludeFromDirectedSnapshot(ctx.DeviceConfig(), m.BaseModuleName()) {
 			installAsFake = true
 		}

 		// installSnapshot installs prebuilts and json flag files
 		snapshotOutputs = append(snapshotOutputs, installSnapshot(m, installAsFake)...)
 		// just gather headers and notice files here, because they are to be deduplicated
 		if l, ok := m.linker.(snapshotLibraryInterface); ok {
 			headers = append(headers, l.snapshotHeaders()...)
 		}

 		if len(m.NoticeFiles()) > 0 {
 			noticeName := ctx.ModuleName(m) + ".txt"
 			noticeOut := filepath.Join(noticeDir, noticeName)
 			// skip already copied notice file
 			if !installedNotices[noticeOut] {
 				installedNotices[noticeOut] = true
 				snapshotOutputs = append(snapshotOutputs, combineNoticesRule(ctx, m.NoticeFiles(), noticeOut))
 			}
 		}
 	})

 	// install all headers after removing duplicates
 	for _, header := range android.FirstUniquePaths(headers) {
 		snapshotOutputs = append(snapshotOutputs, copyFile(ctx, header, filepath.Join(includeDir, header.String()), c.fake))
 	}

 	// All artifacts are ready. Sort them to normalize ninja and then zip.
 	sort.Slice(snapshotOutputs, func(i, j int) bool {
 		return snapshotOutputs[i].String() < snapshotOutputs[j].String()
 	})

 	zipPath := android.PathForOutput(
 		ctx,
 		snapshotDir,
 		c.name+"-"+ctx.Config().DeviceName()+".zip")
 	zipRule := android.NewRuleBuilder(pctx, ctx)

 	// filenames in rspfile from FlagWithRspFileInputList might be single-quoted. Remove it with tr
 	snapshotOutputList := android.PathForOutput(
 		ctx,
 		snapshotDir,
 		c.name+"-"+ctx.Config().DeviceName()+"_list")
 	rspFile := snapshotOutputList.ReplaceExtension(ctx, "rsp")
 	zipRule.Command().
 		Text("tr").
 		FlagWithArg("-d ", "\\'").
 		FlagWithRspFileInputList("< ", rspFile, snapshotOutputs).
 		FlagWithOutput("> ", snapshotOutputList)

 	zipRule.Temporary(snapshotOutputList)

 	zipRule.Command().
 		BuiltTool("soong_zip").
 		FlagWithOutput("-o ", zipPath).
 		FlagWithArg("-C ", android.PathForOutput(ctx, snapshotDir).String()).
 		FlagWithInput("-l ", snapshotOutputList)

 	zipRule.Build(zipPath.String(), c.name+" snapshot "+zipPath.String())
 	zipRule.DeleteTemporaryFiles()
 	c.snapshotZipFile = android.OptionalPathForPath(zipPath)
 }

 func (c *snapshotSingleton) MakeVars(ctx android.MakeVarsContext) {
 	ctx.Strict(
 		c.makeVar,
 		c.snapshotZipFile.String())
 }
	// Copyright 2020 The Android Open Source Project
	//
	// Licensed under the Apache License, Version 2.0 (the "License");
	// you may not use this file except in compliance with the License.
	// You may obtain a copy of the License at
	//
	// http://www.apache.org/licenses/LICENSE-2.0
	//
	// Unless required by applicable law or agreed to in writing, software
	// distributed under the License is distributed on an "AS IS" BASIS,
	// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	// See the License for the specific language governing permissions and
	// limitations under the License.
	package cc

	// This file contains singletons to capture vendor and recovery snapshot. They consist of prebuilt
	// modules under AOSP so older vendor and recovery can be built with a newer system in a single
	// source tree.

	import (
	"encoding/json"
	"path/filepath"
	"sort"
	"strings"

	"android/soong/android"
	)

	var vendorSnapshotSingleton = snapshotSingleton{
	"vendor",
	"SOONG_VENDOR_SNAPSHOT_ZIP",
	android.OptionalPath{},
	true,
	vendorSnapshotImageSingleton,
	false, /* fake */
	}

	var vendorFakeSnapshotSingleton = snapshotSingleton{
	"vendor",
	"SOONG_VENDOR_FAKE_SNAPSHOT_ZIP",
	android.OptionalPath{},
	true,
	vendorSnapshotImageSingleton,
	true, /* fake */
	}

	var recoverySnapshotSingleton = snapshotSingleton{
	"recovery",
	"SOONG_RECOVERY_SNAPSHOT_ZIP",
	android.OptionalPath{},
	false,
	recoverySnapshotImageSingleton,
	false, /* fake */
	}

	func VendorSnapshotSingleton() android.Singleton {
	return &vendorSnapshotSingleton
	}

	func VendorFakeSnapshotSingleton() android.Singleton {
	return &vendorFakeSnapshotSingleton
	}

	func RecoverySnapshotSingleton() android.Singleton {
	return &recoverySnapshotSingleton
	}

	type snapshotSingleton struct {
	// Name, e.g., "vendor", "recovery", "ramdisk".
	name string

	// Make variable that points to the snapshot file, e.g.,
	// "SOONG_RECOVERY_SNAPSHOT_ZIP".
	makeVar string

	// Path to the snapshot zip file.
	snapshotZipFile android.OptionalPath

	// Whether the image supports VNDK extension modules.
	supportsVndkExt bool

	// Implementation of the image interface specific to the image
	// associated with this snapshot (e.g., specific to the vendor image,
	// recovery image, etc.).
	image snapshotImage

	// Whether this singleton is for fake snapshot or not.
	// Fake snapshot is a snapshot whose prebuilt binaries and headers are empty.
	// It is much faster to generate, and can be used to inspect dependencies.
	fake bool
	}

	// Determine if a dir under source tree is an SoC-owned proprietary directory based
	// on vendor snapshot configuration
	// Examples: device/, vendor/
	func isVendorProprietaryPath(dir string, deviceConfig android.DeviceConfig) bool {
	return VendorSnapshotSingleton().(*snapshotSingleton).image.isProprietaryPath(dir, deviceConfig)
	}

	// Determine if a dir under source tree is an SoC-owned proprietary directory based
	// on recovery snapshot configuration
	// Examples: device/, vendor/
	func isRecoveryProprietaryPath(dir string, deviceConfig android.DeviceConfig) bool {
	return RecoverySnapshotSingleton().(*snapshotSingleton).image.isProprietaryPath(dir, deviceConfig)
	}

	func isVendorProprietaryModule(ctx android.BaseModuleContext) bool {
	// Any module in a vendor proprietary path is a vendor proprietary
	// module.
	if isVendorProprietaryPath(ctx.ModuleDir(), ctx.DeviceConfig()) {
	return true
	}

	// However if the module is not in a vendor proprietary path, it may
	// still be a vendor proprietary module. This happens for cc modules
	// that are excluded from the vendor snapshot, and it means that the
	// vendor has assumed control of the framework-provided module.
	if c, ok := ctx.Module().(*Module); ok {
	if c.ExcludeFromVendorSnapshot() {
	return true
	}
	}

	return false
	}

	func isRecoveryProprietaryModule(ctx android.BaseModuleContext) bool {

	// Any module in a recovery proprietary path is a recovery proprietary
	// module.
	if isRecoveryProprietaryPath(ctx.ModuleDir(), ctx.DeviceConfig()) {
	return true
	}

	// However if the module is not in a recovery proprietary path, it may
	// still be a recovery proprietary module. This happens for cc modules
	// that are excluded from the recovery snapshot, and it means that the
	// vendor has assumed control of the framework-provided module.

	if c, ok := ctx.Module().(*Module); ok {
	if c.ExcludeFromRecoverySnapshot() {
	return true
	}
	}

	return false
	}

	// Determines if the module is a candidate for snapshot.
	func isSnapshotAware(cfg android.DeviceConfig, m *Module, inProprietaryPath bool, apexInfo android.ApexInfo, image snapshotImage) bool {
	if !m.Enabled() \|\| m.Properties.HideFromMake {
	return false
	}
	// When android/prebuilt.go selects between source and prebuilt, it sets
	// HideFromMake on the other one to avoid duplicate install rules in make.
	if m.IsHideFromMake() {
	return false
	}
	// skip proprietary modules, but (for the vendor snapshot only)
	// include all VNDK (static)
	if inProprietaryPath && (!image.includeVndk() \|\| !m.IsVndk()) {
	return false
	}
	// If the module would be included based on its path, check to see if
	// the module is marked to be excluded. If so, skip it.
	if image.excludeFromSnapshot(m) {
	return false
	}
	if m.Target().Os.Class != android.Device {
	return false
	}
	if m.Target().NativeBridge == android.NativeBridgeEnabled {
	return false
	}
	// the module must be installed in target image
	if !apexInfo.IsForPlatform() \|\| m.isSnapshotPrebuilt() \|\| !image.inImage(m)() {
	return false
	}
	// skip kernel_headers which always depend on vendor
	if _, ok := m.linker.(*kernelHeadersDecorator); ok {
	return false
	}
	// skip llndk_library and llndk_headers which are backward compatible
	if m.IsLlndk() {
	return false
	}
	if _, ok := m.linker.(*llndkStubDecorator); ok {
	return false
	}
	if _, ok := m.linker.(*llndkHeadersDecorator); ok {
	return false
	}

	// Libraries
	if l, ok := m.linker.(snapshotLibraryInterface); ok {
	if m.sanitize != nil {
	// scs and hwasan export both sanitized and unsanitized variants for static and header
	// Always use unsanitized variants of them.
	for _, t := range []SanitizerType{scs, hwasan} {
	if !l.shared() && m.sanitize.isSanitizerEnabled(t) {
	return false
	}
	}
	// cfi also exports both variants. But for static, we capture both.
	// This is because cfi static libraries can't be linked from non-cfi modules,
	// and vice versa. This isn't the case for scs and hwasan sanitizers.
	if !l.static() && !l.shared() && m.sanitize.isSanitizerEnabled(cfi) {
	return false
	}
	}
	if l.static() {
	return m.outputFile.Valid() && !image.private(m)
	}
	if l.shared() {
	if !m.outputFile.Valid() {
	return false
	}
	if image.includeVndk() {
	if !m.IsVndk() {
	return true
	}
	return m.IsVndkExt()
	}
	}
	return true
	}

	// Binaries and Objects
	if m.binary() \|\| m.object() {
	return m.outputFile.Valid()
	}

	return false
	}

	// This is to be saved as .json files, which is for development/vendor_snapshot/update.py.
	// These flags become Android.bp snapshot module properties.
	type snapshotJsonFlags struct {
	ModuleName string `json:",omitempty"`
	RelativeInstallPath string `json:",omitempty"`
	AndroidMkSuffix string `json:",omitempty"`

	// library flags
	ExportedDirs []string `json:",omitempty"`
	ExportedSystemDirs []string `json:",omitempty"`
	ExportedFlags []string `json:",omitempty"`
	Sanitize string `json:",omitempty"`
	SanitizeMinimalDep bool `json:",omitempty"`
	SanitizeUbsanDep bool `json:",omitempty"`

	// binary flags
	Symlinks []string `json:",omitempty"`

	// dependencies
	SharedLibs []string `json:",omitempty"`
	RuntimeLibs []string `json:",omitempty"`
	Required []string `json:",omitempty"`

	// extra config files
	InitRc []string `json:",omitempty"`
	VintfFragments []string `json:",omitempty"`
	}

	func (c *snapshotSingleton) GenerateBuildActions(ctx android.SingletonContext) {
	if !c.image.shouldGenerateSnapshot(ctx) {
	return
	}

	var snapshotOutputs android.Paths

	/*
	Vendor snapshot zipped artifacts directory structure:
	{SNAPSHOT_ARCH}/
	arch-{TARGET_ARCH}-{TARGET_ARCH_VARIANT}/
	shared/
	(.so shared libraries)
	static/
	(.a static libraries)
	header/
	(header only libraries)
	binary/
	(executable binaries)
	object/
	(.o object files)
	arch-{TARGET_2ND_ARCH}-{TARGET_2ND_ARCH_VARIANT}/
	shared/
	(.so shared libraries)
	static/
	(.a static libraries)
	header/
	(header only libraries)
	binary/
	(executable binaries)
	object/
	(.o object files)
	NOTICE_FILES/
	(notice files, e.g. libbase.txt)
	configs/
	(config files, e.g. init.rc files, vintf_fragments.xml files, etc.)
	include/
	(header files of same directory structure with source tree)
	*/

	snapshotDir := c.name + "-snapshot"
	if c.fake {
	// If this is a fake snapshot singleton, place all files under fake/ subdirectory to avoid
	// collision with real snapshot files
	snapshotDir = filepath.Join("fake", snapshotDir)
	}
	snapshotArchDir := filepath.Join(snapshotDir, ctx.DeviceConfig().DeviceArch())

	includeDir := filepath.Join(snapshotArchDir, "include")
	configsDir := filepath.Join(snapshotArchDir, "configs")
	noticeDir := filepath.Join(snapshotArchDir, "NOTICE_FILES")

	installedNotices := make(map[string]bool)
	installedConfigs := make(map[string]bool)

	var headers android.Paths

	copyFile := func(ctx android.SingletonContext, path android.Path, out string, fake bool) android.OutputPath {
	if fake {
	// All prebuilt binaries and headers are installed by copyFile function. This makes a fake
	// snapshot just touch prebuilts and headers, rather than installing real files.
	return writeStringToFileRule(ctx, "", out)
	} else {
	return copyFileRule(ctx, path, out)
	}
	}

	// installSnapshot function copies prebuilt file (.so, .a, or executable) and json flag file.
	// For executables, init_rc and vintf_fragments files are also copied.
	installSnapshot := func(m *Module, fake bool) android.Paths {
	targetArch := "arch-" + m.Target().Arch.ArchType.String()
	if m.Target().Arch.ArchVariant != "" {
	targetArch += "-" + m.Target().Arch.ArchVariant
	}

	var ret android.Paths

	prop := snapshotJsonFlags{}

	// Common properties among snapshots.
	prop.ModuleName = ctx.ModuleName(m)
	if c.supportsVndkExt && m.IsVndkExt() {
	// vndk exts are installed to /vendor/lib(64)?/vndk(-sp)?
	if m.isVndkSp() {
	prop.RelativeInstallPath = "vndk-sp"
	} else {
	prop.RelativeInstallPath = "vndk"
	}
	} else {
	prop.RelativeInstallPath = m.RelativeInstallPath()
	}
	prop.AndroidMkSuffix = m.Properties.SubName
	prop.RuntimeLibs = m.Properties.SnapshotRuntimeLibs
	prop.Required = m.RequiredModuleNames()
	for _, path := range m.InitRc() {
	prop.InitRc = append(prop.InitRc, filepath.Join("configs", path.Base()))
	}
	for _, path := range m.VintfFragments() {
	prop.VintfFragments = append(prop.VintfFragments, filepath.Join("configs", path.Base()))
	}

	// install config files. ignores any duplicates.
	for _, path := range append(m.InitRc(), m.VintfFragments()...) {
	out := filepath.Join(configsDir, path.Base())
	if !installedConfigs[out] {
	installedConfigs[out] = true
	ret = append(ret, copyFile(ctx, path, out, fake))
	}
	}

	var propOut string

	if l, ok := m.linker.(snapshotLibraryInterface); ok {
	exporterInfo := ctx.ModuleProvider(m, FlagExporterInfoProvider).(FlagExporterInfo)

	// library flags
	prop.ExportedFlags = exporterInfo.Flags
	for _, dir := range exporterInfo.IncludeDirs {
	prop.ExportedDirs = append(prop.ExportedDirs, filepath.Join("include", dir.String()))
	}
	for _, dir := range exporterInfo.SystemIncludeDirs {
	prop.ExportedSystemDirs = append(prop.ExportedSystemDirs, filepath.Join("include", dir.String()))
	}
	// shared libs dependencies aren't meaningful on static or header libs
	if l.shared() {
	prop.SharedLibs = m.Properties.SnapshotSharedLibs
	}
	if l.static() && m.sanitize != nil {
	prop.SanitizeMinimalDep = m.sanitize.Properties.MinimalRuntimeDep \|\| enableMinimalRuntime(m.sanitize)
	prop.SanitizeUbsanDep = m.sanitize.Properties.UbsanRuntimeDep \|\| enableUbsanRuntime(m.sanitize)
	}

	var libType string
	if l.static() {
	libType = "static"
	} else if l.shared() {
	libType = "shared"
	} else {
	libType = "header"
	}

	var stem string

	// install .a or .so
	if libType != "header" {
	libPath := m.outputFile.Path()
	stem = libPath.Base()
	if l.static() && m.sanitize != nil && m.sanitize.isSanitizerEnabled(cfi) {
	// both cfi and non-cfi variant for static libraries can exist.
	// attach .cfi to distinguish between cfi and non-cfi.
	// e.g. libbase.a -> libbase.cfi.a
	ext := filepath.Ext(stem)
	stem = strings.TrimSuffix(stem, ext) + ".cfi" + ext
	prop.Sanitize = "cfi"
	prop.ModuleName += ".cfi"
	}
	snapshotLibOut := filepath.Join(snapshotArchDir, targetArch, libType, stem)
	ret = append(ret, copyFile(ctx, libPath, snapshotLibOut, fake))
	} else {
	stem = ctx.ModuleName(m)
	}

	propOut = filepath.Join(snapshotArchDir, targetArch, libType, stem+".json")
	} else if m.binary() {
	// binary flags
	prop.Symlinks = m.Symlinks()
	prop.SharedLibs = m.Properties.SnapshotSharedLibs

	// install bin
	binPath := m.outputFile.Path()
	snapshotBinOut := filepath.Join(snapshotArchDir, targetArch, "binary", binPath.Base())
	ret = append(ret, copyFile(ctx, binPath, snapshotBinOut, fake))
	propOut = snapshotBinOut + ".json"
	} else if m.object() {
	// object files aren't installed to the device, so their names can conflict.
	// Use module name as stem.
	objPath := m.outputFile.Path()
	snapshotObjOut := filepath.Join(snapshotArchDir, targetArch, "object",
	ctx.ModuleName(m)+filepath.Ext(objPath.Base()))
	ret = append(ret, copyFile(ctx, objPath, snapshotObjOut, fake))
	propOut = snapshotObjOut + ".json"
	} else {
	ctx.Errorf("unknown module %q in vendor snapshot", m.String())
	return nil
	}

	j, err := json.Marshal(prop)
	if err != nil {
	ctx.Errorf("json marshal to %q failed: %#v", propOut, err)
	return nil
	}
	ret = append(ret, writeStringToFileRule(ctx, string(j), propOut))

	return ret
	}

	ctx.VisitAllModules(func(module android.Module) {
	m, ok := module.(*Module)
	if !ok {
	return
	}

	moduleDir := ctx.ModuleDir(module)
	inProprietaryPath := c.image.isProprietaryPath(moduleDir, ctx.DeviceConfig())
	apexInfo := ctx.ModuleProvider(module, android.ApexInfoProvider).(android.ApexInfo)

	if c.image.excludeFromSnapshot(m) {
	if inProprietaryPath {
	// Error: exclude_from_vendor_snapshot applies
	// to framework-path modules only.
	ctx.Errorf("module %q in vendor proprietary path %q may not use \"exclude_from_vendor_snapshot: true\"", m.String(), moduleDir)
	return
	}
	}

	if !isSnapshotAware(ctx.DeviceConfig(), m, inProprietaryPath, apexInfo, c.image) {
	return
	}

	// If we are using directed snapshot and a module is not included in the
	// list, we will still include the module as if it was a fake module.
	// The reason is that soong needs all the dependencies to be present, even
	// if they are not using during the build.
	installAsFake := c.fake
	if c.image.excludeFromDirectedSnapshot(ctx.DeviceConfig(), m.BaseModuleName()) {
	installAsFake = true
	}

	// installSnapshot installs prebuilts and json flag files
	snapshotOutputs = append(snapshotOutputs, installSnapshot(m, installAsFake)...)
	// just gather headers and notice files here, because they are to be deduplicated
	if l, ok := m.linker.(snapshotLibraryInterface); ok {
	headers = append(headers, l.snapshotHeaders()...)
	}

	if len(m.NoticeFiles()) > 0 {
	noticeName := ctx.ModuleName(m) + ".txt"
	noticeOut := filepath.Join(noticeDir, noticeName)
	// skip already copied notice file
	if !installedNotices[noticeOut] {
	installedNotices[noticeOut] = true
	snapshotOutputs = append(snapshotOutputs, combineNoticesRule(ctx, m.NoticeFiles(), noticeOut))
	}
	}
	})

	// install all headers after removing duplicates
	for _, header := range android.FirstUniquePaths(headers) {
	snapshotOutputs = append(snapshotOutputs, copyFile(ctx, header, filepath.Join(includeDir, header.String()), c.fake))
	}

	// All artifacts are ready. Sort them to normalize ninja and then zip.
	sort.Slice(snapshotOutputs, func(i, j int) bool {
	return snapshotOutputs[i].String() < snapshotOutputs[j].String()
	})

	zipPath := android.PathForOutput(
	ctx,
	snapshotDir,
	c.name+"-"+ctx.Config().DeviceName()+".zip")
	zipRule := android.NewRuleBuilder(pctx, ctx)

	// filenames in rspfile from FlagWithRspFileInputList might be single-quoted. Remove it with tr
	snapshotOutputList := android.PathForOutput(
	ctx,
	snapshotDir,
	c.name+"-"+ctx.Config().DeviceName()+"_list")
	rspFile := snapshotOutputList.ReplaceExtension(ctx, "rsp")
	zipRule.Command().
	Text("tr").
	FlagWithArg("-d ", "\\'").
	FlagWithRspFileInputList("< ", rspFile, snapshotOutputs).
	FlagWithOutput("> ", snapshotOutputList)

	zipRule.Temporary(snapshotOutputList)

	zipRule.Command().
	BuiltTool("soong_zip").
	FlagWithOutput("-o ", zipPath).
	FlagWithArg("-C ", android.PathForOutput(ctx, snapshotDir).String()).
	FlagWithInput("-l ", snapshotOutputList)

	zipRule.Build(zipPath.String(), c.name+" snapshot "+zipPath.String())
	zipRule.DeleteTemporaryFiles()
	c.snapshotZipFile = android.OptionalPathForPath(zipPath)
	}

	func (c *snapshotSingleton) MakeVars(ctx android.MakeVarsContext) {
	ctx.Strict(
	c.makeVar,
	c.snapshotZipFile.String())
	}