Delete android/env.go .

Properly plumb the available environment to the configuration instead of
going through the global variable originalEnv.

Test: Presubmit.
Change-Id: Ia1ea753d5e72c02a0dcaa4c0b43bd6e24fc47cec

android/Android.bp

@@ -78,9 +78,6 @@ bootstrap_go_package {
         "variable.go",
         "visibility.go",
         "writedocs.go",
-
-        // Lock down environment access last
-        "env.go",
     ],
     testSrcs: [
         "android_test.go",

android/config.go

@@ -345,7 +345,7 @@ func TestArchConfig(buildDir string, env map[string]string, bp string, fs map[st
 // multiple runs in the same program execution is carried over (such as Bazel
 // context or environment deps).
 func ConfigForAdditionalRun(c Config) (Config, error) {
-	newConfig, err := NewConfig(c.srcDir, c.buildDir, c.moduleListFile)
+	newConfig, err := NewConfig(c.srcDir, c.buildDir, c.moduleListFile, c.env)
 	if err != nil {
 		return Config{}, err
 	}
@@ -356,12 +356,12 @@ func ConfigForAdditionalRun(c Config) (Config, error) {
 
 // NewConfig creates a new Config object. The srcDir argument specifies the path
 // to the root source directory. It also loads the config file, if found.
-func NewConfig(srcDir, buildDir string, moduleListFile string) (Config, error) {
+func NewConfig(srcDir, buildDir string, moduleListFile string, availableEnv map[string]string) (Config, error) {
 	// Make a config with default options.
 	config := &config{
 		ProductVariablesFileName: filepath.Join(buildDir, productVariablesFileName),
 
-		env: originalEnv,
+		env: availableEnv,
 
 		srcDir:            srcDir,
 		buildDir:          buildDir,

android/env.go

@@ -1,40 +0,0 @@
-// Copyright 2015 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 (
-	"android/soong/shared"
-)
-
-// This file supports dependencies on environment variables.  During build
-// manifest generation, any dependency on an environment variable is added to a
-// list.  At the end of the build, a JSON file called soong.environment.used is
-// written containing the current value of all used environment variables. The
-// next time the top-level build script is run, soong_ui parses the compare the
-// contents of the used environment variables, then, if they changed, deletes
-// soong.environment.used to cause a rebuild.
-//
-// The dependency of build.ninja on soong.environment.used is declared in
-// build.ninja.d
-
-var originalEnv map[string]string
-
-func InitEnvironment(envFile string) {
-	var err error
-	originalEnv, err = shared.EnvFromFile(envFile)
-	if err != nil {
-		panic(err)
-	}
-}

cmd/soong_build/main.go

@@ -75,8 +75,8 @@ func newContext(configuration android.Config, prepareBuildActions bool) *android
 	return ctx
 }
 
-func newConfig(srcDir, outDir string) android.Config {
+func newConfig(srcDir, outDir string, availableEnv map[string]string) android.Config {
-	configuration, err := android.NewConfig(srcDir, outDir, bootstrap.CmdlineModuleListFile())
+	configuration, err := android.NewConfig(srcDir, outDir, bootstrap.CmdlineModuleListFile(), availableEnv)
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "%s", err)
 		os.Exit(1)
@@ -188,12 +188,31 @@ func main() {
 
 	shared.ReexecWithDelveMaybe(delveListen, delvePath)
 	android.InitSandbox(topDir)
-	android.InitEnvironment(shared.JoinPath(topDir, outDir, "soong.environment.available"))
 
-	usedVariablesFile := shared.JoinPath(outDir, "soong.environment.used")
+	// soong_ui dumps the available environment variables to
+	// soong.environment.available . Then soong_build itself is run with an empty
+	// environment so that the only way environment variables can be accessed is
+	// using Config, which tracks access to them.
+
+	// At the end of the build, a file called soong.environment.used is written
+	// containing the current value of all used environment variables. The next
+	// time soong_ui is run, it checks whether any environment variables that was
+	// used had changed and if so, it deletes soong.environment.used to cause a
+	// rebuild.
+	//
+	// The dependency of build.ninja on soong.environment.used is declared in
+	// build.ninja.d
+	availableEnvFile := shared.JoinPath(topDir, outDir, "soong.environment.available")
+	usedEnvFile := shared.JoinPath(topDir, outDir, "soong.environment.used")
+	availableEnv, err := shared.EnvFromFile(availableEnvFile)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "error reading available environment file %s: %s\n", availableEnvFile, err)
+		os.Exit(1)
+	}
+
 	// The top-level Blueprints file is passed as the first argument.
 	srcDir := filepath.Dir(flag.Arg(0))
-	configuration := newConfig(srcDir, outDir)
+	configuration := newConfig(srcDir, outDir, availableEnv)
 	extraNinjaDeps := []string{
 		configuration.ProductVariablesFileName,
 		shared.JoinPath(outDir, "soong.environment.used"),
@@ -219,19 +238,19 @@ func main() {
 	}
 
 	doChosenActivity(configuration, extraNinjaDeps)
-	writeUsedVariablesFile(shared.JoinPath(topDir, usedVariablesFile), configuration)
+	writeUsedEnvironmentFile(usedEnvFile, configuration)
 }
 
-func writeUsedVariablesFile(path string, configuration android.Config) {
+func writeUsedEnvironmentFile(path string, configuration android.Config) {
 	data, err := shared.EnvFileContents(configuration.EnvDeps())
 	if err != nil {
-		fmt.Fprintf(os.Stderr, "error writing used variables file %s: %s\n", path, err)
+		fmt.Fprintf(os.Stderr, "error writing used environment file %s: %s\n", path, err)
 		os.Exit(1)
 	}
 
 	err = ioutil.WriteFile(path, data, 0666)
 	if err != nil {
-		fmt.Fprintf(os.Stderr, "error writing used variables file %s: %s\n", path, err)
+		fmt.Fprintf(os.Stderr, "error writing used environment file %s: %s\n", path, err)
 		os.Exit(1)
 	}