Simplify paths for the generated source files

Previously, the generated source files of an aidl_interface were found
under:

out/soong/.intermediate/<path_to_module>/<module>-cpp-gen-<number>/gen

, where <number> is assigned arbitrarily. This caused a problem when the
paths are added to the source path of an IDE. The paths had to be
updated whenever the assigned numbers are changed.

Now, the paths get simpler:

out/soong/.intermediate/<path_to_module>/<module>-cpp-source/gen

This is done by building multiple source files using a single genrule
module.

Bug: 130011113
Test: m
Test: system/tools/aidl/runtests.sh
Merged-In: I308f3c3ced5b2f7ca3a95ea3fd8ab49d8dd9105b
Change-Id: I308f3c3ced5b2f7ca3a95ea3fd8ab49d8dd9105b
(cherry picked from commit b8dceed62c9383b50b4a1f2525c49d78d152b3cf)

1 files changed, 84 insertions, 76 deletions

diff --git a/build/aidl_interface.go b/build/aidl_interface.go
index 99e8a8cd..294d1f5e 100644
--- a/build/aidl_interface.go
+++ b/build/aidl_interface.go
@@ -43,9 +43,14 @@ var (
 
 	pctx = android.NewPackageContext("android/aidl")
 
+	aidlDirPrepareRule = pctx.StaticRule("aidlDirPrepareRule", blueprint.RuleParams{
+		Command: `rm -rf "${outDir}" && mkdir -p "${outDir}" && ` +
+			`touch ${out}`,
+		Description: "create ${out}",
+	}, "outDir")
+
 	aidlCppRule = pctx.StaticRule("aidlCppRule", blueprint.RuleParams{
-		Command: `rm -rf "${outDir}" && ` +
-			`mkdir -p "${outDir}" "${headerDir}" && ` +
+		Command: `mkdir -p "${headerDir}" && ` +
 			`${aidlCmd} --lang=${lang} ${optionalFlags} --structured --ninja -d ${out}.d ` +
 			`-h ${headerDir} -o ${outDir} ${imports} ${in}`,
 		Depfile:     "${out}.d",
@@ -55,8 +60,7 @@ var (
 	}, "imports", "lang", "headerDir", "outDir", "optionalFlags")
 
 	aidlJavaRule = pctx.StaticRule("aidlJavaRule", blueprint.RuleParams{
-		Command: `rm -rf "${outDir}" && mkdir -p "${outDir}" && ` +
-			`${aidlCmd} --lang=java ${optionalFlags} --structured --ninja -d ${out}.d ` +
+		Command: `${aidlCmd} --lang=java ${optionalFlags} --structured --ninja -d ${out}.d ` +
 			`-o ${outDir} ${imports} ${in}`,
 		Depfile:     "${out}.d",
 		Deps:        blueprint.DepsGCC,
@@ -127,7 +131,7 @@ func isRelativePath(path string) bool {
 }
 
 type aidlGenProperties struct {
-	Input    string // a single aidl file
+	Srcs     []string
 	AidlRoot string // base directory for the input aidl file
 	Imports  []string
 	Lang     string // target language [java|cpp|ndk]
@@ -141,6 +145,10 @@ type aidlGenRule struct {
 
 	properties aidlGenProperties
 
+	implicitInputs android.Paths
+	importFlags    string
+
+	genOutDir    android.ModuleGenPath
 	genHeaderDir android.ModuleGenPath
 	genOutputs   android.WritablePaths
 }
@@ -149,24 +157,10 @@ var _ android.SourceFileProducer = (*aidlGenRule)(nil)
 var _ genrule.SourceFileGenerator = (*aidlGenRule)(nil)
 
 func (g *aidlGenRule) GenerateAndroidBuildActions(ctx android.ModuleContext) {
-	// g.properties.Input = some_dir/pkg/to/IFoo.aidl
-	// g.properties.AidlRoot = some_dir
-	// input = <module_root>/some_dir/pkg/to/IFoo.aidl
-	// outDir = out/soong/.intermediate/..../gen/
-	// outFile = out/soong/.intermediates/..../gen/pkg/to/IFoo.{java|cpp}
-	input := android.PathForModuleSrc(ctx, g.properties.Input)
-	input = android.PathWithModuleSrcSubDir(ctx, input, g.properties.AidlRoot)
-	outDir := android.PathForModuleGen(ctx)
-	var outFile android.WritablePath
-	if g.properties.Lang == langJava {
-		outFile = android.PathForModuleGen(ctx, pathtools.ReplaceExtension(input.Rel(), "java"))
-	} else {
-		outFile = android.PathForModuleGen(ctx, pathtools.ReplaceExtension(input.Rel(), "cpp"))
-	}
-	g.genOutputs = []android.WritablePath{outFile}
+	genDirTimestamp := android.PathForModuleGen(ctx, "timestamp")
+	g.implicitInputs = append(g.implicitInputs, genDirTimestamp)
 
 	var importPaths []string
-	var checkApiTimestamps android.Paths
 	ctx.VisitDirectDeps(func(dep android.Module) {
 		if importedAidl, ok := dep.(*aidlInterface); ok {
 			importPaths = append(importPaths, importedAidl.properties.Full_import_paths...)
@@ -174,12 +168,38 @@ func (g *aidlGenRule) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 			// When compiling an AIDL interface, also make sure that each
 			// version of the interface is compatible with its previous version
 			for _, path := range api.checkApiTimestamps {
-				checkApiTimestamps = append(checkApiTimestamps, path)
+				g.implicitInputs = append(g.implicitInputs, path)
 			}
 		}
 	})
+	g.importFlags = strings.Join(wrap("-I", importPaths, ""), " ")
 
-	imports := strings.Join(wrap("-I", importPaths, ""), " ")
+	srcs := android.PathsWithModuleSrcSubDir(ctx, android.PathsForModuleSrc(ctx, g.properties.Srcs), g.properties.AidlRoot)
+
+	g.genOutDir = android.PathForModuleGen(ctx)
+	g.genHeaderDir = android.PathForModuleGen(ctx, "include")
+	for _, src := range srcs {
+		g.genOutputs = append(g.genOutputs, g.generateBuildActionsForSingleAidl(ctx, src))
+	}
+
+	// This is to clean genOutDir before generating any file
+	ctx.ModuleBuild(pctx, android.ModuleBuildParams{
+		Rule:      aidlDirPrepareRule,
+		Implicits: srcs,
+		Output:    genDirTimestamp,
+		Args: map[string]string{
+			"outDir": g.genOutDir.String(),
+		},
+	})
+}
+
+func (g *aidlGenRule) generateBuildActionsForSingleAidl(ctx android.ModuleContext, src android.Path) android.WritablePath {
+	var outFile android.WritablePath
+	if g.properties.Lang == langJava {
+		outFile = android.PathForModuleGen(ctx, pathtools.ReplaceExtension(src.Rel(), "java"))
+	} else {
+		outFile = android.PathForModuleGen(ctx, pathtools.ReplaceExtension(src.Rel(), "cpp"))
+	}
 
 	var optionalFlags []string
 	if g.properties.Version != "" {
@@ -189,19 +209,18 @@ func (g *aidlGenRule) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 	if g.properties.Lang == langJava {
 		ctx.ModuleBuild(pctx, android.ModuleBuildParams{
 			Rule:      aidlJavaRule,
-			Input:     input,
-			Implicits: checkApiTimestamps,
-			Outputs:   g.genOutputs,
+			Input:     src,
+			Implicits: g.implicitInputs,
+			Output:    outFile,
 			Args: map[string]string{
-				"imports":       imports,
-				"outDir":        outDir.String(),
+				"imports":       g.importFlags,
+				"outDir":        g.genOutDir.String(),
 				"optionalFlags": strings.Join(optionalFlags, " "),
 			},
 		})
 	} else {
-		g.genHeaderDir = android.PathForModuleGen(ctx, "include")
-		typeName := strings.TrimSuffix(filepath.Base(input.Rel()), ".aidl")
-		packagePath := filepath.Dir(input.Rel())
+		typeName := strings.TrimSuffix(filepath.Base(src.Rel()), ".aidl")
+		packagePath := filepath.Dir(src.Rel())
 		baseName := typeName
 		// TODO(b/111362593): aidl_to_cpp_common.cpp uses heuristics to figure out if
 		//   an interface name has a leading I. Those same heuristics have been
@@ -235,19 +254,21 @@ func (g *aidlGenRule) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 
 		ctx.ModuleBuild(pctx, android.ModuleBuildParams{
 			Rule:            aidlCppRule,
-			Input:           input,
-			Implicits:       checkApiTimestamps,
-			Outputs:         g.genOutputs,
+			Input:           src,
+			Implicits:       g.implicitInputs,
+			Output:          outFile,
 			ImplicitOutputs: headers,
 			Args: map[string]string{
-				"imports":       imports,
+				"imports":       g.importFlags,
 				"lang":          aidlLang,
 				"headerDir":     g.genHeaderDir.String(),
-				"outDir":        outDir.String(),
+				"outDir":        g.genOutDir.String(),
 				"optionalFlags": strings.Join(optionalFlags, " "),
 			},
 		})
 	}
+
+	return outFile
 }
 
 func (g *aidlGenRule) GeneratedSourceFiles() android.Paths {
@@ -679,7 +700,7 @@ func aidlInterfaceHook(mctx android.LoadHookContext, i *aidlInterface) {
 }
 
 func addCppLibrary(mctx android.LoadHookContext, i *aidlInterface, version string, lang string) string {
-	cppSourceGen := i.versionedName(version) + "-" + lang + "-gen"
+	cppSourceGen := i.versionedName(version) + "-" + lang + "-source"
 	cppModuleGen := i.versionedName(version) + "-" + lang
 
 	srcs, base := i.srcsForVersion(mctx, version)
@@ -690,30 +711,22 @@ func addCppLibrary(mctx android.LoadHookContext, i *aidlInterface, version strin
 		return ""
 	}
 
-	var cppGeneratedSources []string
-
 	genLog := false
 	if lang == langCpp {
 		genLog = proptools.Bool(i.properties.Backend.Cpp.Gen_log)
 	}
 
-	for idx, source := range srcs {
-		// Use idx to distinguish genrule modules. typename is not appropriate
-		// as it is possible to have identical type names in different packages.
-		cppSourceGenName := cppSourceGen + "-" + strconv.Itoa(idx)
-		mctx.CreateModule(android.ModuleFactoryAdaptor(aidlGenFactory), &nameProperties{
-			Name: proptools.StringPtr(cppSourceGenName),
-		}, &aidlGenProperties{
-			Input:    source,
-			AidlRoot: base,
-			Imports:  concat(i.properties.Imports, []string{i.ModuleBase.Name()}),
-			Lang:     lang,
-			BaseName: i.ModuleBase.Name(),
-			GenLog:   genLog,
-			Version:  version,
-		})
-		cppGeneratedSources = append(cppGeneratedSources, cppSourceGenName)
-	}
+	mctx.CreateModule(android.ModuleFactoryAdaptor(aidlGenFactory), &nameProperties{
+		Name: proptools.StringPtr(cppSourceGen),
+	}, &aidlGenProperties{
+		Srcs:     srcs,
+		AidlRoot: base,
+		Imports:  concat(i.properties.Imports, []string{i.ModuleBase.Name()}),
+		Lang:     lang,
+		BaseName: i.ModuleBase.Name(),
+		GenLog:   genLog,
+		Version:  version,
+	})
 
 	importExportDependencies := wrap("", i.properties.Imports, "-"+lang)
 	var libJSONCppDependency []string
@@ -745,9 +758,9 @@ func addCppLibrary(mctx android.LoadHookContext, i *aidlInterface, version strin
 		Owner:                     i.properties.Owner,
 		Vendor_available:          i.properties.Vendor_available,
 		Defaults:                  []string{"aidl-cpp-module-defaults"},
-		Generated_sources:         cppGeneratedSources,
-		Generated_headers:         cppGeneratedSources,
-		Export_generated_headers:  cppGeneratedSources,
+		Generated_sources:         []string{cppSourceGen},
+		Generated_headers:         []string{cppSourceGen},
+		Export_generated_headers:  []string{cppSourceGen},
 		Static:                    staticLib{Whole_static_libs: libJSONCppDependency},
 		Shared:                    sharedLib{Shared_libs: libJSONCppDependency, Export_shared_lib_headers: libJSONCppDependency},
 		Shared_libs:               importExportDependencies,
@@ -762,7 +775,7 @@ func addCppLibrary(mctx android.LoadHookContext, i *aidlInterface, version strin
 }
 
 func addJavaLibrary(mctx android.LoadHookContext, i *aidlInterface, version string) string {
-	javaSourceGen := i.versionedName(version) + "-java-gen"
+	javaSourceGen := i.versionedName(version) + "-java-source"
 	javaModuleGen := i.versionedName(version) + "-java"
 
 	srcs, base := i.srcsForVersion(mctx, version)
@@ -773,23 +786,18 @@ func addJavaLibrary(mctx android.LoadHookContext, i *aidlInterface, version stri
 		return ""
 	}
 
-	var javaGeneratedSources []string
 	sdkVersion := proptools.StringDefault(i.properties.Backend.Java.Sdk_version, "system_current")
 
-	for idx, source := range srcs {
-		javaSourceGenName := javaSourceGen + "-" + strconv.Itoa(idx)
-		mctx.CreateModule(android.ModuleFactoryAdaptor(aidlGenFactory), &nameProperties{
-			Name: proptools.StringPtr(javaSourceGenName),
-		}, &aidlGenProperties{
-			Input:    source,
-			AidlRoot: base,
-			Imports:  concat(i.properties.Imports, []string{i.ModuleBase.Name()}),
-			Lang:     langJava,
-			BaseName: i.ModuleBase.Name(),
-			Version:  version,
-		})
-		javaGeneratedSources = append(javaGeneratedSources, javaSourceGenName)
-	}
+	mctx.CreateModule(android.ModuleFactoryAdaptor(aidlGenFactory), &nameProperties{
+		Name: proptools.StringPtr(javaSourceGen),
+	}, &aidlGenProperties{
+		Srcs:     srcs,
+		AidlRoot: base,
+		Imports:  concat(i.properties.Imports, []string{i.ModuleBase.Name()}),
+		Lang:     langJava,
+		BaseName: i.ModuleBase.Name(),
+		Version:  version,
+	})
 
 	mctx.CreateModule(android.ModuleFactoryAdaptor(java.LibraryFactory), &javaProperties{
 		Name:              proptools.StringPtr(javaModuleGen),
@@ -799,7 +807,7 @@ func addJavaLibrary(mctx android.LoadHookContext, i *aidlInterface, version stri
 		No_framework_libs: proptools.BoolPtr(true),
 		Sdk_version:       proptools.StringPtr(sdkVersion),
 		Static_libs:       wrap("", i.properties.Imports, "-java"),
-		Srcs:              wrap(":", javaGeneratedSources, ""),
+		Srcs:              []string{":" + javaSourceGen},
 	})
 
 	return javaModuleGen