1// Copyright 2020 Google Inc. All rights reserved. 2// 3// Licensed under the Apache License, Version 2.0 (the "License"); 4// you may not use this file except in compliance with the License. 5// You may obtain a copy of the License at 6// 7// http://www.apache.org/licenses/LICENSE-2.0 8// 9// Unless required by applicable law or agreed to in writing, software 10// distributed under the License is distributed on an "AS IS" BASIS, 11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12// See the License for the specific language governing permissions and 13// limitations under the License. 14 15package bp2build 16 17import ( 18 "fmt" 19 "os" 20 "path/filepath" 21 "strings" 22 23 "android/soong/android" 24 "android/soong/bazel" 25 "android/soong/shared" 26) 27 28func deleteFilesExcept(ctx *CodegenContext, rootOutputPath android.OutputPath, except []BazelFile) { 29 // Delete files that should no longer be present. 30 bp2buildDirAbs := shared.JoinPath(ctx.topDir, rootOutputPath.String()) 31 32 filesToDelete := make(map[string]struct{}) 33 err := filepath.Walk(bp2buildDirAbs, 34 func(path string, info os.FileInfo, err error) error { 35 if err != nil { 36 return err 37 } 38 if !info.IsDir() { 39 relPath, err := filepath.Rel(bp2buildDirAbs, path) 40 if err != nil { 41 return err 42 } 43 filesToDelete[relPath] = struct{}{} 44 } 45 return nil 46 }) 47 if err != nil { 48 fmt.Printf("ERROR reading %s: %s", bp2buildDirAbs, err) 49 os.Exit(1) 50 } 51 52 for _, bazelFile := range except { 53 filePath := filepath.Join(bazelFile.Dir, bazelFile.Basename) 54 delete(filesToDelete, filePath) 55 } 56 for f, _ := range filesToDelete { 57 absPath := shared.JoinPath(bp2buildDirAbs, f) 58 if err := os.RemoveAll(absPath); err != nil { 59 fmt.Printf("ERROR deleting %s: %s", absPath, err) 60 os.Exit(1) 61 } 62 } 63} 64 65// Codegen is the backend of bp2build. The code generator is responsible for 66// writing .bzl files that are equivalent to Android.bp files that are capable 67// of being built with Bazel. 68func Codegen(ctx *CodegenContext) *CodegenMetrics { 69 // This directory stores BUILD files that could be eventually checked-in. 70 bp2buildDir := android.PathForOutput(ctx, "bp2build") 71 72 res, errs := GenerateBazelTargets(ctx, true) 73 if len(errs) > 0 { 74 errMsgs := make([]string, len(errs)) 75 for i, err := range errs { 76 errMsgs[i] = fmt.Sprintf("%q", err) 77 } 78 fmt.Printf("ERROR: Encountered %d error(s): \nERROR: %s", len(errs), strings.Join(errMsgs, "\n")) 79 os.Exit(1) 80 } 81 bp2buildFiles := CreateBazelFiles(ctx.Config(), nil, res.buildFileToTargets, ctx.mode) 82 writeFiles(ctx, bp2buildDir, bp2buildFiles) 83 // Delete files under the bp2build root which weren't just written. An 84 // alternative would have been to delete the whole directory and write these 85 // files. However, this would regenerate files which were otherwise unchanged 86 // since the last bp2build run, which would have negative incremental 87 // performance implications. 88 deleteFilesExcept(ctx, bp2buildDir, bp2buildFiles) 89 90 injectionFiles, err := CreateSoongInjectionDirFiles(ctx, res.metrics) 91 if err != nil { 92 fmt.Printf("%s\n", err.Error()) 93 os.Exit(1) 94 } 95 writeFiles(ctx, android.PathForOutput(ctx, bazel.SoongInjectionDirName), injectionFiles) 96 return &res.metrics 97} 98 99// Wrapper function that will be responsible for all files in soong_injection directory 100// This includes 101// 1. config value(s) that are hardcoded in Soong 102// 2. product_config variables 103func CreateSoongInjectionDirFiles(ctx *CodegenContext, metrics CodegenMetrics) ([]BazelFile, error) { 104 var ret []BazelFile 105 106 productConfigFiles, err := CreateProductConfigFiles(ctx) 107 if err != nil { 108 return nil, err 109 } 110 ret = append(ret, productConfigFiles...) 111 injectionFiles, err := soongInjectionFiles(ctx.Config(), metrics) 112 if err != nil { 113 return nil, err 114 } 115 ret = append(ret, injectionFiles...) 116 return ret, nil 117} 118 119// Get the output directory and create it if it doesn't exist. 120func getOrCreateOutputDir(outputDir android.OutputPath, ctx android.PathContext, dir string) android.OutputPath { 121 dirPath := outputDir.Join(ctx, dir) 122 if err := android.CreateOutputDirIfNonexistent(dirPath, os.ModePerm); err != nil { 123 fmt.Printf("ERROR: path %s: %s", dirPath, err.Error()) 124 } 125 return dirPath 126} 127 128// writeFiles materializes a list of BazelFile rooted at outputDir. 129func writeFiles(ctx android.PathContext, outputDir android.OutputPath, files []BazelFile) { 130 for _, f := range files { 131 p := getOrCreateOutputDir(outputDir, ctx, f.Dir).Join(ctx, f.Basename) 132 if err := writeFile(p, f.Contents); err != nil { 133 panic(fmt.Errorf("Failed to write %q (dir %q) due to %q", f.Basename, f.Dir, err)) 134 } 135 } 136} 137 138func writeFile(pathToFile android.OutputPath, content string) error { 139 // These files are made editable to allow users to modify and iterate on them 140 // in the source tree. 141 return android.WriteFileToOutputDir(pathToFile, []byte(content), 0644) 142} 143