1 // Copyright 2015 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 15 package android 16 17 import ( 18 "os" 19 "strings" 20 21 "android/soong/env" 22 ) 23 24 // This file supports dependencies on environment variables. During build manifest generation, 25 // any dependency on an environment variable is added to a list. During the singleton phase 26 // a JSON file is written containing the current value of all used environment variables. 27 // The next time the top-level build script is run, it uses the soong_env executable to 28 // compare the contents of the environment variables, rewriting the file if necessary to cause 29 // a manifest regeneration. 30 31 var originalEnv map[string]string 32 33 func init() { 34 originalEnv = make(map[string]string) 35 for _, env := range os.Environ() { 36 idx := strings.IndexRune(env, '=') 37 if idx != -1 { 38 originalEnv[env[:idx]] = env[idx+1:] 39 } 40 } 41 os.Clearenv() 42 } 43 44 func EnvSingleton() Singleton { 45 return &envSingleton{} 46 } 47 48 type envSingleton struct{} 49 50 func (c *envSingleton) GenerateBuildActions(ctx SingletonContext) { 51 envDeps := ctx.Config().EnvDeps() 52 53 envFile := PathForOutput(ctx, ".soong.environment") 54 if ctx.Failed() { 55 return 56 } 57 58 err := env.WriteEnvFile(envFile.String(), envDeps) 59 if err != nil { 60 ctx.Errorf(err.Error()) 61 } 62 63 ctx.AddNinjaFileDeps(envFile.String()) 64 } 65
