Sandbox soong_build by changing to root directory

This relands I12a0f907753fefd1997ab8b4ea2ac331234093cf along with
a fix to blueprint for absolute paths.

Store the current working directory and then change to the root
directory so that all file accesses must go through helpers in
the android package that properly track dependencies.

Change-Id: I24ac485677aa102eec1a2521d16820da6ee1ae77
Fixes: 146437378
Test: m checkbuild
Test: m OUT_DIR=/tmp/out nothing

1 files changed, 6 insertions, 9 deletions

diff --git a/java/jdeps.go b/java/jdeps.go
index fccc40fa8..49e3de3cc 100644
--- a/java/jdeps.go
+++ b/java/jdeps.go
@@ -17,7 +17,6 @@ package java
 import (
 	"encoding/json"
 	"fmt"
-	"os"
 
 	"android/soong/android"
 )
@@ -92,23 +91,21 @@ func (j *jdepsGeneratorSingleton) GenerateBuildActions(ctx android.SingletonCont
 		moduleInfos[name] = dpInfo
 	})
 
-	jfpath := android.PathForOutput(ctx, jdepsJsonFileName).String()
+	jfpath := android.PathForOutput(ctx, jdepsJsonFileName)
 	err := createJsonFile(moduleInfos, jfpath)
 	if err != nil {
 		ctx.Errorf(err.Error())
 	}
 }
 
-func createJsonFile(moduleInfos map[string]android.IdeInfo, jfpath string) error {
-	file, err := os.Create(jfpath)
+func createJsonFile(moduleInfos map[string]android.IdeInfo, jfpath android.WritablePath) error {
+	buf, err := json.MarshalIndent(moduleInfos, "", "\t")
 	if err != nil {
-		return fmt.Errorf("Failed to create file: %s, relative: %v", jdepsJsonFileName, err)
+		return fmt.Errorf("JSON marshal of java deps failed: %s", err)
 	}
-	defer file.Close()
-	buf, err := json.MarshalIndent(moduleInfos, "", "\t")
+	err = android.WriteFileToOutputDir(jfpath, buf, 0666)
 	if err != nil {
-		return fmt.Errorf("Write file failed: %s, relative: %v", jdepsJsonFileName, err)
+		return fmt.Errorf("Writing java deps to %s failed: %s", jfpath.String(), err)
 	}
-	fmt.Fprintf(file, string(buf))
 	return nil
 }