Make mk2rbc output paths relative to android root

Previously, mk2rbc would output absolute paths in the load statements.
This caused issues with the new module resolution logic in rbcrun,
and is not something we'd want to check in anyways.

Bug: 280685526
Test: go test
Change-Id: Iae6e3f6be9cecc8e19b6e1fd33c5575ff6864654

mk2rbc/mk2rbc.go

@@ -163,6 +163,21 @@ var ignoredDefines = map[string]bool{
 
 var identifierFullMatchRegex = regexp.MustCompile("^[a-zA-Z_][a-zA-Z0-9_]*$")
 
+func RelativeToCwd(path string) (string, error) {
+	cwd, err := os.Getwd()
+	if err != nil {
+		return "", err
+	}
+	path, err = filepath.Rel(cwd, path)
+	if err != nil {
+		return "", err
+	}
+	if strings.HasPrefix(path, "../") {
+		return "", fmt.Errorf("Could not make path relative to current working directory: " + path)
+	}
+	return path, nil
+}
+
 // Conversion request parameters
 type Request struct {
 	MkFile          string    // file to convert
@@ -320,6 +335,14 @@ func (gctx *generationContext) emitPreamble() {
 	loadedSubConfigs := make(map[string]string)
 	for _, mi := range gctx.starScript.inherited {
 		uri := mi.path
+		if strings.HasPrefix(uri, "/") && !strings.HasPrefix(uri, "//") {
+			var err error
+			uri, err = RelativeToCwd(uri)
+			if err != nil {
+				panic(err)
+			}
+			uri = "//" + uri
+		}
 		if m, ok := loadedSubConfigs[uri]; ok {
 			// No need to emit load statement, but fix module name.
 			mi.moduleLocalName = m

mk2rbc/mk2rbc/mk2rbc.go

@@ -187,7 +187,7 @@ func main() {
 			quit(fmt.Errorf("the product launcher input variables file failed to convert"))
 		}
 
-		err := writeGenerated(*launcher, mk2rbc.Launcher(outputFilePath(files[0]), outputFilePath(*inputVariables),
+		err := writeGenerated(*launcher, mk2rbc.Launcher(outputModulePath(files[0]), outputModulePath(*inputVariables),
 			mk2rbc.MakePath2ModuleName(files[0])))
 		if err != nil {
 			fmt.Fprintf(os.Stderr, "%s: %s", files[0], err)
@@ -205,7 +205,7 @@ func main() {
 			quit(fmt.Errorf("the board launcher input variables file failed to convert"))
 		}
 		err := writeGenerated(*boardlauncher, mk2rbc.BoardLauncher(
-			outputFilePath(files[0]), outputFilePath(*inputVariables)))
+			outputModulePath(files[0]), outputModulePath(*inputVariables)))
 		if err != nil {
 			fmt.Fprintf(os.Stderr, "%s: %s", files[0], err)
 			ok = false
@@ -402,6 +402,15 @@ func outputFilePath(mkFile string) string {
 	return path
 }
 
+func outputModulePath(mkFile string) string {
+	path := outputFilePath(mkFile)
+	path, err := mk2rbc.RelativeToCwd(path)
+	if err != nil {
+		panic(err)
+	}
+	return "//" + path
+}
+
 func writeGenerated(path string, contents string) error {
 	if err := os.MkdirAll(filepath.Dir(path), os.ModeDir|os.ModePerm); err != nil {
 		return err

mk2rbc/soong_variables_test.go

@@ -42,8 +42,8 @@ func TestSoongVariables(t *testing.T) {
 		{"BUILD_ID", VarClassSoong, starlarkTypeString},
 		{"PLATFORM_SDK_VERSION", VarClassSoong, starlarkTypeInt},
 		{"DEVICE_PACKAGE_OVERLAYS", VarClassSoong, starlarkTypeList},
-		{"ENABLE_CFI", VarClassSoong, starlarkTypeBool},
+		{"ENABLE_CFI", VarClassSoong, starlarkTypeString},
-		{"ENABLE_PREOPT", VarClassSoong, starlarkTypeBool},
+		{"ENABLE_PREOPT", VarClassSoong, starlarkTypeString},
 	}}
 	if !reflect.DeepEqual(expected, actual) {
 		t.Errorf("\nExpected: %v\n  Actual: %v", expected, actual)