platform_build_soong/cc/vendor_snapshot.go

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// 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().(LinkableInterface); 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().(LinkableInterface); ok {
if c.ExcludeFromRecoverySnapshot() {
return true
}
}
return false
}
// Determines if the module is a candidate for snapshot.
func isSnapshotAware(cfg android.DeviceConfig, m LinkableInterface, inProprietaryPath bool, apexInfo android.ApexInfo, image snapshotImage) bool {
if !m.Enabled() || m.HiddenFromMake() {
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 m.KernelHeadersDecorator() {
return false
}
if m.IsLlndk() {
return false
}
// Libraries
if sanitizable, ok := m.(PlatformSanitizeable); ok && sanitizable.IsSnapshotLibrary() {
if sanitizable.SanitizePropDefined() {
Add cfi static libraries to vendor snapshot CFI modules can't link against non-CFI static libraries, and vice versa. So without capturing both CFI and non-CFI static libraries, vendor modules won't be able to use CFI, which will be a critical security hole. This captures both CFI and non-CFI variants of all static libraries for vendor snapshot, except for those whose cfi are explicitly disabled. For example, suppose that "libfoo" is defined as follows. cc_library_static { name: "libfoo", vendor_available: true, } As it doesn't have cfi disabled, two libraries "libfoo.a" and "libfoo.cfi.a" will be captured. When installed, vendor snapshot module for "libfoo" will look like: vendor_snapshot_static { name: "libfoo", src: "libfoo.a", cfi: { src: "libfoo.cfi.a", }, } The build system will recognize the "cfi" property, and will create both CFI and non-CFI variant, allowing any modules to link against "libfoo" safely, no matter whether CFI is enabled or not. Two clarification: 1) The reason why we don't create separate modules is that DepsMutator runs before sanitize mutators. CFI and non-CFI variant of a library should exist in a single module. 2) We can't capture CFI variant if the source module explicitly disables cfi variant by specifying the following. sanitize: { cfi: false, } In this case, only non-CFI variant will be created for the vendor snapshot module. Bug: 65377115 Test: m dist vendor-snapshot && install && build against snapshot Change-Id: Idbf3e3205d581800d6093c8d6cf6152374129ba4
2020-07-29 19:32:10 +08:00
// 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 !sanitizable.Shared() && sanitizable.IsSanitizerEnabled(t) {
return false
}
}
Add cfi static libraries to vendor snapshot CFI modules can't link against non-CFI static libraries, and vice versa. So without capturing both CFI and non-CFI static libraries, vendor modules won't be able to use CFI, which will be a critical security hole. This captures both CFI and non-CFI variants of all static libraries for vendor snapshot, except for those whose cfi are explicitly disabled. For example, suppose that "libfoo" is defined as follows. cc_library_static { name: "libfoo", vendor_available: true, } As it doesn't have cfi disabled, two libraries "libfoo.a" and "libfoo.cfi.a" will be captured. When installed, vendor snapshot module for "libfoo" will look like: vendor_snapshot_static { name: "libfoo", src: "libfoo.a", cfi: { src: "libfoo.cfi.a", }, } The build system will recognize the "cfi" property, and will create both CFI and non-CFI variant, allowing any modules to link against "libfoo" safely, no matter whether CFI is enabled or not. Two clarification: 1) The reason why we don't create separate modules is that DepsMutator runs before sanitize mutators. CFI and non-CFI variant of a library should exist in a single module. 2) We can't capture CFI variant if the source module explicitly disables cfi variant by specifying the following. sanitize: { cfi: false, } In this case, only non-CFI variant will be created for the vendor snapshot module. Bug: 65377115 Test: m dist vendor-snapshot && install && build against snapshot Change-Id: Idbf3e3205d581800d6093c8d6cf6152374129ba4
2020-07-29 19:32:10 +08:00
// 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 !sanitizable.Static() && !sanitizable.Shared() && sanitizable.IsSanitizerEnabled(cfi) {
Add cfi static libraries to vendor snapshot CFI modules can't link against non-CFI static libraries, and vice versa. So without capturing both CFI and non-CFI static libraries, vendor modules won't be able to use CFI, which will be a critical security hole. This captures both CFI and non-CFI variants of all static libraries for vendor snapshot, except for those whose cfi are explicitly disabled. For example, suppose that "libfoo" is defined as follows. cc_library_static { name: "libfoo", vendor_available: true, } As it doesn't have cfi disabled, two libraries "libfoo.a" and "libfoo.cfi.a" will be captured. When installed, vendor snapshot module for "libfoo" will look like: vendor_snapshot_static { name: "libfoo", src: "libfoo.a", cfi: { src: "libfoo.cfi.a", }, } The build system will recognize the "cfi" property, and will create both CFI and non-CFI variant, allowing any modules to link against "libfoo" safely, no matter whether CFI is enabled or not. Two clarification: 1) The reason why we don't create separate modules is that DepsMutator runs before sanitize mutators. CFI and non-CFI variant of a library should exist in a single module. 2) We can't capture CFI variant if the source module explicitly disables cfi variant by specifying the following. sanitize: { cfi: false, } In this case, only non-CFI variant will be created for the vendor snapshot module. Bug: 65377115 Test: m dist vendor-snapshot && install && build against snapshot Change-Id: Idbf3e3205d581800d6093c8d6cf6152374129ba4
2020-07-29 19:32:10 +08:00
return false
}
}
if sanitizable.Static() {
return sanitizable.OutputFile().Valid() && !image.private(m)
}
if sanitizable.Shared() {
if !sanitizable.OutputFile().Valid() {
return false
}
if image.includeVndk() {
if !sanitizable.IsVndk() {
return true
}
return sanitizable.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"`
// 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 LinkableInterface, 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.RuntimeLibs = m.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 m.IsSnapshotLibrary() {
exporterInfo := ctx.ModuleProvider(m.Module(), FlagExporterInfoProvider).(FlagExporterInfo)
Add cfi static libraries to vendor snapshot CFI modules can't link against non-CFI static libraries, and vice versa. So without capturing both CFI and non-CFI static libraries, vendor modules won't be able to use CFI, which will be a critical security hole. This captures both CFI and non-CFI variants of all static libraries for vendor snapshot, except for those whose cfi are explicitly disabled. For example, suppose that "libfoo" is defined as follows. cc_library_static { name: "libfoo", vendor_available: true, } As it doesn't have cfi disabled, two libraries "libfoo.a" and "libfoo.cfi.a" will be captured. When installed, vendor snapshot module for "libfoo" will look like: vendor_snapshot_static { name: "libfoo", src: "libfoo.a", cfi: { src: "libfoo.cfi.a", }, } The build system will recognize the "cfi" property, and will create both CFI and non-CFI variant, allowing any modules to link against "libfoo" safely, no matter whether CFI is enabled or not. Two clarification: 1) The reason why we don't create separate modules is that DepsMutator runs before sanitize mutators. CFI and non-CFI variant of a library should exist in a single module. 2) We can't capture CFI variant if the source module explicitly disables cfi variant by specifying the following. sanitize: { cfi: false, } In this case, only non-CFI variant will be created for the vendor snapshot module. Bug: 65377115 Test: m dist vendor-snapshot && install && build against snapshot Change-Id: Idbf3e3205d581800d6093c8d6cf6152374129ba4
2020-07-29 19:32:10 +08:00
// 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 m.Shared() {
prop.SharedLibs = m.SnapshotSharedLibs()
}
if sanitizable, ok := m.(PlatformSanitizeable); ok {
if sanitizable.Static() && sanitizable.SanitizePropDefined() {
prop.SanitizeMinimalDep = sanitizable.MinimalRuntimeDep() || sanitizable.MinimalRuntimeNeeded()
prop.SanitizeUbsanDep = sanitizable.UbsanRuntimeDep() || sanitizable.UbsanRuntimeNeeded()
}
}
var libType string
if m.Static() {
libType = "static"
} else if m.Shared() {
libType = "shared"
} else {
libType = "header"
}
var stem string
// install .a or .so
if libType != "header" {
libPath := m.OutputFile().Path()
stem = libPath.Base()
if sanitizable, ok := m.(PlatformSanitizeable); ok {
if sanitizable.Static() && sanitizable.SanitizePropDefined() && sanitizable.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"
}
Add cfi static libraries to vendor snapshot CFI modules can't link against non-CFI static libraries, and vice versa. So without capturing both CFI and non-CFI static libraries, vendor modules won't be able to use CFI, which will be a critical security hole. This captures both CFI and non-CFI variants of all static libraries for vendor snapshot, except for those whose cfi are explicitly disabled. For example, suppose that "libfoo" is defined as follows. cc_library_static { name: "libfoo", vendor_available: true, } As it doesn't have cfi disabled, two libraries "libfoo.a" and "libfoo.cfi.a" will be captured. When installed, vendor snapshot module for "libfoo" will look like: vendor_snapshot_static { name: "libfoo", src: "libfoo.a", cfi: { src: "libfoo.cfi.a", }, } The build system will recognize the "cfi" property, and will create both CFI and non-CFI variant, allowing any modules to link against "libfoo" safely, no matter whether CFI is enabled or not. Two clarification: 1) The reason why we don't create separate modules is that DepsMutator runs before sanitize mutators. CFI and non-CFI variant of a library should exist in a single module. 2) We can't capture CFI variant if the source module explicitly disables cfi variant by specifying the following. sanitize: { cfi: false, } In this case, only non-CFI variant will be created for the vendor snapshot module. Bug: 65377115 Test: m dist vendor-snapshot && install && build against snapshot Change-Id: Idbf3e3205d581800d6093c8d6cf6152374129ba4
2020-07-29 19:32:10 +08:00
}
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.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.(LinkableInterface)
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 m.IsSnapshotLibrary() {
headers = append(headers, m.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())
}