Add relative_install_path property to prebuilt_etc

This supports a more consistent property across modules for specifying a
subdirectory to install a file into for prebuilt_etc modules.

Updates bpfix to rewrite `sub_dir` to `relative_install_path`.

Test: gotest prebuilt_etc_test
Test: gotest bpfix_test
Bug: 156568187
Change-Id: Idd05cd2178c46e290764a3b708faa8275818ca1e

etc/prebuilt_etc.go

@@ -42,9 +42,12 @@ type prebuiltEtcProperties struct {
 	// Source file of this prebuilt.
 	Src *string `android:"path,arch_variant"`
 
-	// optional subdirectory under which this file is installed into
+	// optional subdirectory under which this file is installed into, cannot be specified with relative_install_path, prefer relative_install_path
 	Sub_dir *string `android:"arch_variant"`
 
+	// optional subdirectory under which this file is installed into, cannot be specified with sub_dir
+	Relative_install_path *string `android:"arch_variant"`
+
 	// optional name for the installed file. If unspecified, name of the module is used as the file name
 	Filename *string `android:"arch_variant"`
 
@@ -158,7 +161,10 @@ func (p *PrebuiltEtc) OutputFile() android.OutputPath {
 }
 
 func (p *PrebuiltEtc) SubDir() string {
-	return android.String(p.properties.Sub_dir)
+	if subDir := proptools.String(p.properties.Sub_dir); subDir != "" {
+		return subDir
+	}
+	return proptools.String(p.properties.Relative_install_path)
 }
 
 func (p *PrebuiltEtc) Installable() bool {
@@ -181,13 +187,17 @@ func (p *PrebuiltEtc) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 	}
 	p.outputFilePath = android.PathForModuleOut(ctx, filename).OutputPath
 
+	if p.properties.Sub_dir != nil && p.properties.Relative_install_path != nil {
+		ctx.PropertyErrorf("sub_dir", "relative_install_path is set. Cannot set sub_dir")
+	}
+
 	// If soc install dir was specified and SOC specific is set, set the installDirPath to the specified
 	// socInstallDirBase.
 	installBaseDir := p.installDirBase
 	if ctx.SocSpecific() && p.socInstallDirBase != "" {
 		installBaseDir = p.socInstallDirBase
 	}
-	p.installDirPath = android.PathForModuleInstall(ctx, installBaseDir, proptools.String(p.properties.Sub_dir))
+	p.installDirPath = android.PathForModuleInstall(ctx, installBaseDir, p.SubDir())
 
 	// This ensures that outputFilePath has the correct name for others to
 	// use, as the source file may have a different name.

etc/prebuilt_etc_test.go

@@ -49,7 +49,7 @@ func TestMain(m *testing.M) {
 	os.Exit(run())
 }
 
-func testPrebuiltEtc(t *testing.T, bp string) (*android.TestContext, android.Config) {
+func testPrebuiltEtcContext(t *testing.T, bp string) (*android.TestContext, android.Config) {
 	fs := map[string][]byte{
 		"foo.conf": nil,
 		"bar.conf": nil,
@@ -67,6 +67,14 @@ func testPrebuiltEtc(t *testing.T, bp string) (*android.TestContext, android.Con
 	ctx.RegisterModuleType("prebuilt_firmware", PrebuiltFirmwareFactory)
 	ctx.RegisterModuleType("prebuilt_dsp", PrebuiltDSPFactory)
 	ctx.Register(config)
+
+	return ctx, config
+}
+
+func testPrebuiltEtc(t *testing.T, bp string) (*android.TestContext, android.Config) {
+	t.Helper()
+
+	ctx, config := testPrebuiltEtcContext(t, bp)
 	_, errs := ctx.ParseFileList(".", []string{"Android.bp"})
 	android.FailIfErrored(t, errs)
 	_, errs = ctx.PrepareBuildActions(config)
@@ -75,6 +83,24 @@ func testPrebuiltEtc(t *testing.T, bp string) (*android.TestContext, android.Con
 	return ctx, config
 }
 
+func testPrebuiltEtcError(t *testing.T, pattern, bp string) {
+	t.Helper()
+
+	ctx, config := testPrebuiltEtcContext(t, bp)
+	_, errs := ctx.ParseFileList(".", []string{"Android.bp"})
+	if len(errs) > 0 {
+		android.FailIfNoMatchingErrors(t, pattern, errs)
+		return
+	}
+
+	_, errs = ctx.PrepareBuildActions(config)
+	if len(errs) > 0 {
+		android.FailIfNoMatchingErrors(t, pattern, errs)
+		return
+	}
+
+	t.Fatalf("missing expected error %q (0 errors are returned)", pattern)
+}
 func TestPrebuiltEtcVariants(t *testing.T) {
 	ctx, _ := testPrebuiltEtc(t, `
 		prebuilt_etc {
@@ -184,6 +210,33 @@ func TestPrebuiltEtcAndroidMk(t *testing.T) {
 	}
 }
 
+func TestPrebuiltEtcRelativeInstallPathInstallDirPath(t *testing.T) {
+	ctx, _ := testPrebuiltEtc(t, `
+		prebuilt_etc {
+			name: "foo.conf",
+			src: "foo.conf",
+			relative_install_path: "bar",
+		}
+	`)
+
+	p := ctx.ModuleForTests("foo.conf", "android_arm64_armv8-a").Module().(*PrebuiltEtc)
+	expected := buildDir + "/target/product/test_device/system/etc/bar"
+	if p.installDirPath.String() != expected {
+		t.Errorf("expected %q, got %q", expected, p.installDirPath.String())
+	}
+}
+
+func TestPrebuiltEtcCannotSetRelativeInstallPathAndSubDir(t *testing.T) {
+	testPrebuiltEtcError(t, "relative_install_path is set. Cannot set sub_dir", `
+		prebuilt_etc {
+			name: "foo.conf",
+			src: "foo.conf",
+			sub_dir: "bar",
+			relative_install_path: "bar",
+		}
+	`)
+}
+
 func TestPrebuiltEtcHost(t *testing.T) {
 	ctx, _ := testPrebuiltEtc(t, `
 		prebuilt_etc_host {