[DO NOT MERGE] Generate RBE socket address randomly for each invocation of soong. am: 498a732edb

Original change: https://googleplex-android-review.googlesource.com/c/platform/build/soong/+/12595309

Change-Id: I474582214c26fab393c5b1cd48a932bdfa98fe62

ui/build/config.go

@@ -152,7 +152,8 @@ func NewConfig(ctx Context, args ...string) Config {
 	// Tell python not to spam the source tree with .pyc files.
 	ret.environ.Set("PYTHONDONTWRITEBYTECODE", "1")
 
-	ret.environ.Set("TMPDIR", absPath(ctx, ret.TempDir()))
+	tmpDir := absPath(ctx, ret.TempDir())
+	ret.environ.Set("TMPDIR", tmpDir)
 
 	// Precondition: the current directory is the top of the source tree
 	if _, err := os.Stat(srcDirFileCheck); err != nil {
@@ -218,12 +219,19 @@ func NewConfig(ctx Context, args ...string) Config {
 	} else {
 		content = strconv.FormatInt(time.Now().Unix(), 10)
 	}
+
 	err := ioutil.WriteFile(buildDateTimeFile, []byte(content), 0777)
 	if err != nil {
 		ctx.Fatalln("Failed to write BUILD_DATETIME to file:", err)
 	}
 	ret.environ.Set("BUILD_DATETIME_FILE", buildDateTimeFile)
 
+	if ret.UseRBE() {
+		for k, v := range getRBEVars(ctx, tmpDir) {
+			ret.environ.Set(k, v)
+		}
+	}
+
 	return Config{ret}
 }
 

ui/build/rbe.go

@@ -15,7 +15,10 @@
 package build
 
 import (
+	"fmt"
+	"math/rand"
 	"path/filepath"
+	"time"
 
 	"android/soong/ui/metrics"
 )
@@ -24,6 +27,11 @@ const bootstrapCmd = "bootstrap"
 const rbeLeastNProcs = 2500
 const rbeLeastNFiles = 16000
 
+func getRBEVars(ctx Context, tmpDir string) map[string]string {
+	rand.Seed(time.Now().UnixNano())
+	return map[string]string{"RBE_server_address": fmt.Sprintf("unix://%v/reproxy_%v.sock", tmpDir, rand.Intn(1000))}
+}
+
 func startRBE(ctx Context, config Config) {
 	ctx.BeginTrace(metrics.RunSetupTool, "rbe_bootstrap")
 	defer ctx.EndTrace()