1 files changed, 55 insertions, 0 deletions
diff --git a/cmd/soong_env/soong_env.go b/cmd/soong_env/soong_env.go
new file mode 100644
index 00000000..933e525a
--- /dev/null
+++ b/cmd/soong_env/soong_env.go
@@ -0,0 +1,55 @@
+// 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.
+
+// soong_glob is the command line tool that checks if the list of files matching a glob has
+// changed, and only updates the output file list if it has changed.  It is used to optimize
+// out build.ninja regenerations when non-matching files are added.  See
+// android/soong/common/glob.go for a longer description.
+package main
+
+import (
+	"flag"
+	"fmt"
+	"os"
+
+	"android/soong/env"
+)
+
+func usage() {
+	fmt.Fprintf(os.Stderr, "usage: soong_env env_file\n")
+	fmt.Fprintf(os.Stderr, "exits with success if the environment varibles in env_file match\n")
+	fmt.Fprintf(os.Stderr, "the current environment\n")
+	flag.PrintDefaults()
+	os.Exit(2)
+}
+
+func main() {
+	flag.Parse()
+
+	if flag.NArg() != 1 {
+		usage()
+	}
+
+	stale, err := env.StaleEnvFile(flag.Arg(0))
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "error: %s\n", err.Error())
+		os.Exit(1)
+	}
+
+	if stale {
+		os.Exit(1)
+	}
+
+	os.Exit(0)
+}