// Copyright 2020 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 android import ( "bytes" "errors" "fmt" "io/ioutil" "os" "os/exec" "path/filepath" "runtime" "strings" "sync" "github.com/google/blueprint/bootstrap" "android/soong/bazel" "android/soong/shared" ) type CqueryRequestType int const ( getAllFiles CqueryRequestType = iota getCcObjectFiles getAllFilesAndCcObjectFiles ) // Map key to describe bazel cquery requests. type cqueryKey struct { label string requestType CqueryRequestType archType ArchType } type BazelContext interface { // The below methods involve queuing cquery requests to be later invoked // by bazel. If any of these methods return (_, false), then the request // has been queued to be run later. // Returns result files built by building the given bazel target label. GetAllFiles(label string, archType ArchType) ([]string, bool) // Returns object files produced by compiling the given cc-related target. // Retrieves these files from Bazel's CcInfo provider. GetCcObjectFiles(label string, archType ArchType) ([]string, bool) // Returns the results of GetAllFiles and GetCcObjectFiles in a single query (in that order). GetAllFilesAndCcObjectFiles(label string, archType ArchType) ([]string, []string, bool) // ** End cquery methods // Issues commands to Bazel to receive results for all cquery requests // queued in the BazelContext. InvokeBazel() error // Returns true if bazel is enabled for the given configuration. BazelEnabled() bool // Returns the bazel output base (the root directory for all bazel intermediate outputs). OutputBase() string // Returns build statements which should get registered to reflect Bazel's outputs. BuildStatementsToRegister() []bazel.BuildStatement } // A context object which tracks queued requests that need to be made to Bazel, // and their results after the requests have been made. type bazelContext struct { homeDir string bazelPath string outputBase string workspaceDir string buildDir string metricsDir string requests map[cqueryKey]bool // cquery requests that have not yet been issued to Bazel requestMutex sync.Mutex // requests can be written in parallel results map[cqueryKey]string // Results of cquery requests after Bazel invocations // Build statements which should get registered to reflect Bazel's outputs. buildStatements []bazel.BuildStatement } var _ BazelContext = &bazelContext{} // A bazel context to use when Bazel is disabled. type noopBazelContext struct{} var _ BazelContext = noopBazelContext{} // A bazel context to use for tests. type MockBazelContext struct { AllFiles map[string][]string } func (m MockBazelContext) GetAllFiles(label string, archType ArchType) ([]string, bool) { result, ok := m.AllFiles[label] return result, ok } func (m MockBazelContext) GetCcObjectFiles(label string, archType ArchType) ([]string, bool) { result, ok := m.AllFiles[label] return result, ok } func (m MockBazelContext) GetAllFilesAndCcObjectFiles(label string, archType ArchType) ([]string, []string, bool) { result, ok := m.AllFiles[label] return result, result, ok } func (m MockBazelContext) InvokeBazel() error { panic("unimplemented") } func (m MockBazelContext) BazelEnabled() bool { return true } func (m MockBazelContext) OutputBase() string { return "outputbase" } func (m MockBazelContext) BuildStatementsToRegister() []bazel.BuildStatement { return []bazel.BuildStatement{} } var _ BazelContext = MockBazelContext{} func (bazelCtx *bazelContext) GetAllFiles(label string, archType ArchType) ([]string, bool) { result, ok := bazelCtx.cquery(label, getAllFiles, archType) if ok { bazelOutput := strings.TrimSpace(result) return strings.Split(bazelOutput, ", "), true } else { return nil, false } } func (bazelCtx *bazelContext) GetCcObjectFiles(label string, archType ArchType) ([]string, bool) { result, ok := bazelCtx.cquery(label, getCcObjectFiles, archType) if ok { bazelOutput := strings.TrimSpace(result) return strings.Split(bazelOutput, ", "), true } else { return nil, false } } func (bazelCtx *bazelContext) GetAllFilesAndCcObjectFiles(label string, archType ArchType) ([]string, []string, bool) { var allFiles []string var ccObjects []string result, ok := bazelCtx.cquery(label, getAllFilesAndCcObjectFiles, archType) if ok { bazelOutput := strings.TrimSpace(result) splitString := strings.Split(bazelOutput, "|") allFilesString := splitString[0] ccObjectsString := splitString[1] allFiles = strings.Split(allFilesString, ", ") ccObjects = strings.Split(ccObjectsString, ", ") } return allFiles, ccObjects, ok } func (n noopBazelContext) GetAllFiles(label string, archType ArchType) ([]string, bool) { panic("unimplemented") } func (n noopBazelContext) GetCcObjectFiles(label string, archType ArchType) ([]string, bool) { panic("unimplemented") } func (n noopBazelContext) GetAllFilesAndCcObjectFiles(label string, archType ArchType) ([]string, []string, bool) { panic("unimplemented") } func (n noopBazelContext) InvokeBazel() error { panic("unimplemented") } func (m noopBazelContext) OutputBase() string { return "" } func (n noopBazelContext) BazelEnabled() bool { return false } func (m noopBazelContext) BuildStatementsToRegister() []bazel.BuildStatement { return []bazel.BuildStatement{} } func NewBazelContext(c *config) (BazelContext, error) { // TODO(cparsons): Assess USE_BAZEL=1 instead once "mixed Soong/Bazel builds" // are production ready. if c.Getenv("USE_BAZEL_ANALYSIS") != "1" { return noopBazelContext{}, nil } bazelCtx := bazelContext{buildDir: c.buildDir, requests: make(map[cqueryKey]bool)} missingEnvVars := []string{} if len(c.Getenv("BAZEL_HOME")) > 1 { bazelCtx.homeDir = c.Getenv("BAZEL_HOME") } else { missingEnvVars = append(missingEnvVars, "BAZEL_HOME") } if len(c.Getenv("BAZEL_PATH")) > 1 { bazelCtx.bazelPath = c.Getenv("BAZEL_PATH") } else { missingEnvVars = append(missingEnvVars, "BAZEL_PATH") } if len(c.Getenv("BAZEL_OUTPUT_BASE")) > 1 { bazelCtx.outputBase = c.Getenv("BAZEL_OUTPUT_BASE") } else { missingEnvVars = append(missingEnvVars, "BAZEL_OUTPUT_BASE") } if len(c.Getenv("BAZEL_WORKSPACE")) > 1 { bazelCtx.workspaceDir = c.Getenv("BAZEL_WORKSPACE") } else { missingEnvVars = append(missingEnvVars, "BAZEL_WORKSPACE") } if len(c.Getenv("BAZEL_METRICS_DIR")) > 1 { bazelCtx.metricsDir = c.Getenv("BAZEL_METRICS_DIR") } else { missingEnvVars = append(missingEnvVars, "BAZEL_METRICS_DIR") } if len(missingEnvVars) > 0 { return nil, errors.New(fmt.Sprintf("missing required env vars to use bazel: %s", missingEnvVars)) } else { return &bazelCtx, nil } } func (context *bazelContext) BazelMetricsDir() string { return context.metricsDir } func (context *bazelContext) BazelEnabled() bool { return true } // Adds a cquery request to the Bazel request queue, to be later invoked, or // returns the result of the given request if the request was already made. // If the given request was already made (and the results are available), then // returns (result, true). If the request is queued but no results are available, // then returns ("", false). func (context *bazelContext) cquery(label string, requestType CqueryRequestType, archType ArchType) (string, bool) { key := cqueryKey{label, requestType, archType} if result, ok := context.results[key]; ok { return result, true } else { context.requestMutex.Lock() defer context.requestMutex.Unlock() context.requests[key] = true return "", false } } func pwdPrefix() string { // Darwin doesn't have /proc if runtime.GOOS != "darwin" { return "PWD=/proc/self/cwd" } return "" } // Issues the given bazel command with given build label and additional flags. // Returns (stdout, stderr, error). The first and second return values are strings // containing the stdout and stderr of the run command, and an error is returned if // the invocation returned an error code. func (context *bazelContext) issueBazelCommand(runName bazel.RunName, command string, labels []string, extraFlags ...string) (string, string, error) { cmdFlags := []string{"--output_base=" + context.outputBase, command} cmdFlags = append(cmdFlags, labels...) cmdFlags = append(cmdFlags, "--package_path=%workspace%/"+context.intermediatesDir()) cmdFlags = append(cmdFlags, "--profile="+shared.BazelMetricsFilename(context, runName)) // Set default platforms to canonicalized values for mixed builds requests. If these are set // in the bazelrc, they will have values that are non-canonicalized, and thus be invalid. // The actual platform values here may be overridden by configuration transitions from the buildroot. cmdFlags = append(cmdFlags, fmt.Sprintf("--platforms=%s", canonicalizeLabel("//build/bazel/platforms:generic_x86_64"))) cmdFlags = append(cmdFlags, fmt.Sprintf("--extra_toolchains=%s", canonicalizeLabel("//prebuilts/clang/host/linux-x86:all"))) // Explicitly disable downloading rules (such as canonical C++ and Java rules) from the network. cmdFlags = append(cmdFlags, "--experimental_repository_disable_download") cmdFlags = append(cmdFlags, extraFlags...) bazelCmd := exec.Command(context.bazelPath, cmdFlags...) bazelCmd.Dir = context.workspaceDir bazelCmd.Env = append(os.Environ(), "HOME="+context.homeDir, pwdPrefix(), // Disables local host detection of gcc; toolchain information is defined // explicitly in BUILD files. "BAZEL_DO_NOT_DETECT_CPP_TOOLCHAIN=1") stderr := &bytes.Buffer{} bazelCmd.Stderr = stderr if output, err := bazelCmd.Output(); err != nil { return "", string(stderr.Bytes()), fmt.Errorf("bazel command failed. command: [%s], env: [%s], error [%s]", bazelCmd, bazelCmd.Env, stderr) } else { return string(output), string(stderr.Bytes()), nil } } // Returns the string contents of a workspace file that should be output // adjacent to the main bzl file and build file. // This workspace file allows, via local_repository rule, sourcetree-level // BUILD targets to be referenced via @sourceroot. func (context *bazelContext) workspaceFileContents() []byte { formatString := ` # This file is generated by soong_build. Do not edit. local_repository( name = "sourceroot", path = "%s", ) ` return []byte(fmt.Sprintf(formatString, context.workspaceDir)) } func (context *bazelContext) mainBzlFileContents() []byte { // TODO(cparsons): Define configuration transitions programmatically based // on available archs. contents := ` ##################################################### # This file is generated by soong_build. Do not edit. ##################################################### def _x86_64_transition_impl(settings, attr): return { "//command_line_option:platforms": "@sourceroot//build/bazel/platforms:generic_x86_64", } def _x86_transition_impl(settings, attr): return { "//command_line_option:platforms": "@sourceroot//build/bazel/platforms:generic_x86", } def _arm64_transition_impl(settings, attr): return { "//command_line_option:platforms": "@sourceroot//build/bazel/platforms:generic_arm64", } def _arm_transition_impl(settings, attr): return { "//command_line_option:platforms": "@sourceroot//build/bazel/platforms:generic_arm", } x86_64_transition = transition( implementation = _x86_64_transition_impl, inputs = [], outputs = [ "//command_line_option:platforms", ], ) x86_transition = transition( implementation = _x86_transition_impl, inputs = [], outputs = [ "//command_line_option:platforms", ], ) arm64_transition = transition( implementation = _arm64_transition_impl, inputs = [], outputs = [ "//command_line_option:platforms", ], ) arm_transition = transition( implementation = _arm_transition_impl, inputs = [], outputs = [ "//command_line_option:platforms", ], ) def _mixed_build_root_impl(ctx): all_files = ctx.files.deps_x86_64 + ctx.files.deps_x86 + ctx.files.deps_arm64 + ctx.files.deps_arm return [DefaultInfo(files = depset(all_files))] # Rule representing the root of the build, to depend on all Bazel targets that # are required for the build. Building this target will build the entire Bazel # build tree. mixed_build_root = rule( implementation = _mixed_build_root_impl, attrs = { "deps_x86_64" : attr.label_list(cfg = x86_64_transition), "deps_x86" : attr.label_list(cfg = x86_transition), "deps_arm64" : attr.label_list(cfg = arm64_transition), "deps_arm" : attr.label_list(cfg = arm_transition), "_allowlist_function_transition": attr.label(default = "@bazel_tools//tools/allowlists/function_transition_allowlist"), }, ) def _phony_root_impl(ctx): return [] # Rule to depend on other targets but build nothing. # This is useful as follows: building a target of this rule will generate # symlink forests for all dependencies of the target, without executing any # actions of the build. phony_root = rule( implementation = _phony_root_impl, attrs = {"deps" : attr.label_list()}, ) ` return []byte(contents) } // Returns a "canonicalized" corresponding to the given sourcetree-level label. // This abstraction is required because a sourcetree label such as //foo/bar:baz // must be referenced via the local repository prefix, such as // @sourceroot//foo/bar:baz. func canonicalizeLabel(label string) string { if strings.HasPrefix(label, "//") { return "@sourceroot" + label } else { return "@sourceroot//" + label } } func (context *bazelContext) mainBuildFileContents() []byte { // TODO(cparsons): Map label to attribute programmatically; don't use hard-coded // architecture mapping. formatString := ` # This file is generated by soong_build. Do not edit. load(":main.bzl", "mixed_build_root", "phony_root") mixed_build_root(name = "buildroot", deps_x86_64 = [%s], deps_x86 = [%s], deps_arm64 = [%s], deps_arm = [%s], ) phony_root(name = "phonyroot", deps = [":buildroot"], ) ` var deps_x86_64 []string = nil var deps_x86 []string = nil var deps_arm64 []string = nil var deps_arm []string = nil for val, _ := range context.requests { labelString := fmt.Sprintf("\"%s\"", canonicalizeLabel(val.label)) switch getArchString(val) { case "x86_64": deps_x86_64 = append(deps_x86_64, labelString) case "x86": deps_x86 = append(deps_x86, labelString) case "arm64": deps_arm64 = append(deps_arm64, labelString) case "arm": deps_arm = append(deps_arm, labelString) default: panic(fmt.Sprintf("unhandled architecture %s for %v", getArchString(val), val)) } } return []byte(fmt.Sprintf(formatString, strings.Join(deps_x86_64, ",\n "), strings.Join(deps_x86, ",\n "), strings.Join(deps_arm64, ",\n "), strings.Join(deps_arm, ",\n "))) } // Returns the file contents of the buildroot.cquery file that should be used for the cquery // expression in order to obtain information about buildroot and its dependencies. // The contents of this file depend on the bazelContext's requests; requests are enumerated // and grouped by their request type. The data retrieved for each label depends on its // request type. func (context *bazelContext) cqueryStarlarkFileContents() []byte { formatString := ` # This file is generated by soong_build. Do not edit. getAllFilesLabels = { %s } getCcObjectFilesLabels = { %s } getAllFilesAndCcObjectFilesLabels = { %s } def get_all_files(target): return [f.path for f in target.files.to_list()] def get_cc_object_files(target): result = [] linker_inputs = providers(target)["CcInfo"].linking_context.linker_inputs.to_list() for linker_input in linker_inputs: for library in linker_input.libraries: for object in library.objects: result += [object.path] return result def get_arch(target): buildoptions = build_options(target) platforms = build_options(target)["//command_line_option:platforms"] if len(platforms) != 1: # An individual configured target should have only one platform architecture. # Note that it's fine for there to be multiple architectures for the same label, # but each is its own configured target. fail("expected exactly 1 platform for " + str(target.label) + " but got " + str(platforms)) platform_name = build_options(target)["//command_line_option:platforms"][0].name if platform_name == "host": return "HOST" elif not platform_name.startswith("generic_"): fail("expected platform name of the form 'generic_', but was " + str(platforms)) return "UNKNOWN" return platform_name[len("generic_"):] def format(target): id_string = str(target.label) + "|" + get_arch(target) if id_string in getAllFilesLabels: return id_string + ">>" + ', '.join(get_all_files(target)) elif id_string in getCcObjectFilesLabels: return id_string + ">>" + ', '.join(get_cc_object_files(target)) elif id_string in getAllFilesAndCcObjectFilesLabels: return id_string + ">>" + ', '.join(get_all_files(target)) + "|" + ', '.join(get_cc_object_files(target)) else: # This target was not requested via cquery, and thus must be a dependency # of a requested target. return id_string + ">>NONE" ` var getAllFilesDeps []string = nil var getCcObjectFilesDeps []string = nil var getAllFilesAndCcObjectFilesDeps []string = nil for val, _ := range context.requests { labelWithArch := getCqueryId(val) mapEntryString := fmt.Sprintf("%q : True", labelWithArch) switch val.requestType { case getAllFiles: getAllFilesDeps = append(getAllFilesDeps, mapEntryString) case getCcObjectFiles: getCcObjectFilesDeps = append(getCcObjectFilesDeps, mapEntryString) case getAllFilesAndCcObjectFiles: getAllFilesAndCcObjectFilesDeps = append(getAllFilesAndCcObjectFilesDeps, mapEntryString) } } getAllFilesDepsString := strings.Join(getAllFilesDeps, ",\n ") getCcObjectFilesDepsString := strings.Join(getCcObjectFilesDeps, ",\n ") getAllFilesAndCcObjectFilesDepsString := strings.Join(getAllFilesAndCcObjectFilesDeps, ",\n ") return []byte(fmt.Sprintf(formatString, getAllFilesDepsString, getCcObjectFilesDepsString, getAllFilesAndCcObjectFilesDepsString)) } // Returns a workspace-relative path containing build-related metadata required // for interfacing with Bazel. Example: out/soong/bazel. func (context *bazelContext) intermediatesDir() string { return filepath.Join(context.buildDir, "bazel") } // Issues commands to Bazel to receive results for all cquery requests // queued in the BazelContext. func (context *bazelContext) InvokeBazel() error { context.results = make(map[cqueryKey]string) var cqueryOutput string var cqueryErr string var err error intermediatesDirPath := absolutePath(context.intermediatesDir()) if _, err := os.Stat(intermediatesDirPath); os.IsNotExist(err) { err = os.Mkdir(intermediatesDirPath, 0777) } if err != nil { return err } err = ioutil.WriteFile( absolutePath(filepath.Join(context.intermediatesDir(), "main.bzl")), context.mainBzlFileContents(), 0666) if err != nil { return err } err = ioutil.WriteFile( absolutePath(filepath.Join(context.intermediatesDir(), "BUILD.bazel")), context.mainBuildFileContents(), 0666) if err != nil { return err } cqueryFileRelpath := filepath.Join(context.intermediatesDir(), "buildroot.cquery") err = ioutil.WriteFile( absolutePath(cqueryFileRelpath), context.cqueryStarlarkFileContents(), 0666) if err != nil { return err } workspaceFileRelpath := filepath.Join(context.intermediatesDir(), "WORKSPACE.bazel") err = ioutil.WriteFile( absolutePath(workspaceFileRelpath), context.workspaceFileContents(), 0666) if err != nil { return err } buildrootLabel := "//:buildroot" cqueryOutput, cqueryErr, err = context.issueBazelCommand(bazel.CqueryBuildRootRunName, "cquery", []string{fmt.Sprintf("kind(rule, deps(%s))", buildrootLabel)}, "--output=starlark", "--starlark:file="+cqueryFileRelpath) err = ioutil.WriteFile( absolutePath(filepath.Join(context.intermediatesDir(), "cquery.out")), []byte(cqueryOutput), 0666) if err != nil { return err } if err != nil { return err } cqueryResults := map[string]string{} for _, outputLine := range strings.Split(cqueryOutput, "\n") { if strings.Contains(outputLine, ">>") { splitLine := strings.SplitN(outputLine, ">>", 2) cqueryResults[splitLine[0]] = splitLine[1] } } for val, _ := range context.requests { if cqueryResult, ok := cqueryResults[getCqueryId(val)]; ok { context.results[val] = string(cqueryResult) } else { return fmt.Errorf("missing result for bazel target %s. query output: [%s], cquery err: [%s]", getCqueryId(val), cqueryOutput, cqueryErr) } } // Issue an aquery command to retrieve action information about the bazel build tree. // // TODO(cparsons): Use --target_pattern_file to avoid command line limits. var aqueryOutput string aqueryOutput, _, err = context.issueBazelCommand(bazel.AqueryBuildRootRunName, "aquery", []string{fmt.Sprintf("deps(%s)", buildrootLabel), // Use jsonproto instead of proto; actual proto parsing would require a dependency on Bazel's // proto sources, which would add a number of unnecessary dependencies. "--output=jsonproto"}) if err != nil { return err } context.buildStatements, err = bazel.AqueryBuildStatements([]byte(aqueryOutput)) if err != nil { return err } // Issue a build command of the phony root to generate symlink forests for dependencies of the // Bazel build. This is necessary because aquery invocations do not generate this symlink forest, // but some of symlinks may be required to resolve source dependencies of the build. _, _, err = context.issueBazelCommand(bazel.BazelBuildPhonyRootRunName, "build", []string{"//:phonyroot"}) if err != nil { return err } // Clear requests. context.requests = map[cqueryKey]bool{} return nil } func (context *bazelContext) BuildStatementsToRegister() []bazel.BuildStatement { return context.buildStatements } func (context *bazelContext) OutputBase() string { return context.outputBase } // Singleton used for registering BUILD file ninja dependencies (needed // for correctness of builds which use Bazel. func BazelSingleton() Singleton { return &bazelSingleton{} } type bazelSingleton struct{} func (c *bazelSingleton) GenerateBuildActions(ctx SingletonContext) { // bazelSingleton is a no-op if mixed-soong-bazel-builds are disabled. if !ctx.Config().BazelContext.BazelEnabled() { return } // Add ninja file dependencies for files which all bazel invocations require. bazelBuildList := absolutePath(filepath.Join( filepath.Dir(bootstrap.ModuleListFile), "bazel.list")) ctx.AddNinjaFileDeps(bazelBuildList) data, err := ioutil.ReadFile(bazelBuildList) if err != nil { ctx.Errorf(err.Error()) } files := strings.Split(strings.TrimSpace(string(data)), "\n") for _, file := range files { ctx.AddNinjaFileDeps(file) } // Register bazel-owned build statements (obtained from the aquery invocation). for index, buildStatement := range ctx.Config().BazelContext.BuildStatementsToRegister() { if len(buildStatement.Command) < 1 { panic(fmt.Sprintf("unhandled build statement: %s", buildStatement)) } rule := NewRuleBuilder(pctx, ctx) cmd := rule.Command() cmd.Text(fmt.Sprintf("cd %s/execroot/__main__ && %s", ctx.Config().BazelContext.OutputBase(), buildStatement.Command)) for _, outputPath := range buildStatement.OutputPaths { cmd.ImplicitOutput(PathForBazelOut(ctx, outputPath)) } for _, inputPath := range buildStatement.InputPaths { cmd.Implicit(PathForBazelOut(ctx, inputPath)) } // This is required to silence warnings pertaining to unexpected timestamps. Particularly, // some Bazel builtins (such as files in the bazel_tools directory) have far-future // timestamps. Without restat, Ninja would emit warnings that the input files of a // build statement have later timestamps than the outputs. rule.Restat() rule.Build(fmt.Sprintf("bazel %d", index), buildStatement.Mnemonic) } } func getCqueryId(key cqueryKey) string { return canonicalizeLabel(key.label) + "|" + getArchString(key) } func getArchString(key cqueryKey) string { arch := key.archType.Name if len(arch) > 0 { return arch } else { return "x86_64" } }