Export aidl, proto and sysprop generated headers separately

Previously, a cc library that included .aidl, .proto and/or .sysprop
files and exported headers generated from at least one of those types
would actually export generated headers from all of them.

While headers generated from .sysprop files are always exported those
generated from .aidl or .proto should only be exported when explicitly
requested.

This change treats them separately as expected. It has the potential
to break the build as it could reduce the set of headers exported and
so a dependent module that needed those would break. The fix in that
case is to simply add one (or both) of the following to the module
that previously exported those headers:

  aidl: {
    export_aidl_headers: true,
  }

  proto: {
    export_proto_headers: true,
  }

Bug: 180712399
Test: m droid
Change-Id: I488182e27dd423d261443612f98d5c112dd3ef8f

cc/cc_test.go

@@ -4092,7 +4092,6 @@ func TestIncludeDirsExporting(t *testing.T) {
 		)
 	})
 
-	// TODO: fix this test as it exports all generated headers.
 	t.Run("ensure only aidl headers are exported", func(t *testing.T) {
 		ctx := testCc(t, genRuleModules+`
 		cc_library_shared {
@@ -4117,18 +4116,15 @@ func TestIncludeDirsExporting(t *testing.T) {
 				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/aidl/b.h
 				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/aidl/Bnb.h
 				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/aidl/Bpb.h
-				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/proto/a.pb.h
 			`),
 			expectedOrderOnlyDeps(`
 				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/aidl/b.h
 				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/aidl/Bnb.h
 				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/aidl/Bpb.h
-				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/proto/a.pb.h
 			`),
 		)
 	})
 
-	// TODO: fix this test as it exports all generated headers.
 	t.Run("ensure only proto headers are exported", func(t *testing.T) {
 		ctx := testCc(t, genRuleModules+`
 		cc_library_shared {
@@ -4150,22 +4146,17 @@ func TestIncludeDirsExporting(t *testing.T) {
 			`),
 			expectedSystemIncludeDirs(``),
 			expectedGeneratedHeaders(`
-				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/aidl/b.h
-				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/aidl/Bnb.h
-				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/aidl/Bpb.h
 				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/proto/a.pb.h
 			`),
 			expectedOrderOnlyDeps(`
-				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/aidl/b.h
-				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/aidl/Bnb.h
-				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/aidl/Bpb.h
 				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/proto/a.pb.h
 			`),
 		)
 	})
 
-	// TODO: fix this test as it exports all generated headers including public and non-public.
+	// TODO fix this test as it exports the sysprop public and non-public headers irrespective of
-	t.Run("ensure only non-public sysprop headers are exported", func(t *testing.T) {
+	//  which include directory is exported.
+	t.Run("ensure only sysprop headers are exported", func(t *testing.T) {
 		ctx := testCc(t, genRuleModules+`
 		cc_library_shared {
 			name: "libfoo",
@@ -4186,18 +4177,10 @@ func TestIncludeDirsExporting(t *testing.T) {
 			expectedGeneratedHeaders(`
 				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/sysprop/include/a.sysprop.h
 				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/sysprop/public/include/a.sysprop.h
-				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/aidl/b.h
-				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/aidl/Bnb.h
-				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/aidl/Bpb.h
-				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/proto/a.pb.h
 			`),
 			expectedOrderOnlyDeps(`
 				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/sysprop/include/a.sysprop.h
 				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/sysprop/public/include/a.sysprop.h
-				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/aidl/b.h
-				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/aidl/Bnb.h
-				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/aidl/Bpb.h
-				.intermediates/libfoo/android_arm64_armv8-a_shared/gen/proto/a.pb.h
 			`),
 		)
 	})

cc/compiler.go

@@ -230,6 +230,8 @@ type baseCompiler struct {
 	// other modules and filegroups. May include source files that have not yet been translated to
 	// C/C++ (.aidl, .proto, etc.)
 	srcsBeforeGen android.Paths
+
+	generatedSourceInfo
 }
 
 var _ compiler = (*baseCompiler)(nil)
@@ -634,10 +636,11 @@ func (compiler *baseCompiler) compile(ctx ModuleContext, flags Flags, deps PathD
 
 	srcs := append(android.Paths(nil), compiler.srcsBeforeGen...)
 
-	srcs, genDeps := genSources(ctx, srcs, buildFlags)
+	srcs, genDeps, info := genSources(ctx, srcs, buildFlags)
 	pathDeps = append(pathDeps, genDeps...)
 
 	compiler.pathDeps = pathDeps
+	compiler.generatedSourceInfo = info
 	compiler.cFlagsDeps = flags.CFlagsDeps
 
 	// Save src, buildFlags and context

cc/gen.go

@@ -220,8 +220,35 @@ func genWinMsg(ctx android.ModuleContext, srcFile android.Path, flags builderFla
 	return rcFile, headerFile
 }
 
+// Used to communicate information from the genSources method back to the library code that uses
+// it.
+type generatedSourceInfo struct {
+	// The headers created from .proto files
+	protoHeaders android.Paths
+
+	// The files that can be used as order only dependencies in order to ensure that the proto header
+	// files are up to date.
+	protoOrderOnlyDeps android.Paths
+
+	// The headers created from .aidl files
+	aidlHeaders android.Paths
+
+	// The files that can be used as order only dependencies in order to ensure that the aidl header
+	// files are up to date.
+	aidlOrderOnlyDeps android.Paths
+
+	// The headers created from .sysprop files
+	syspropHeaders android.Paths
+
+	// The files that can be used as order only dependencies in order to ensure that the sysprop
+	// header files are up to date.
+	syspropOrderOnlyDeps android.Paths
+}
+
 func genSources(ctx android.ModuleContext, srcFiles android.Paths,
-	buildFlags builderFlags) (android.Paths, android.Paths) {
+	buildFlags builderFlags) (android.Paths, android.Paths, generatedSourceInfo) {
+
+	var info generatedSourceInfo
 
 	var deps android.Paths
 	var rsFiles android.Paths
@@ -258,7 +285,9 @@ func genSources(ctx android.ModuleContext, srcFiles android.Paths,
 		case ".proto":
 			ccFile, headerFile := genProto(ctx, srcFile, buildFlags)
 			srcFiles[i] = ccFile
-			deps = append(deps, headerFile)
+			info.protoHeaders = append(info.protoHeaders, headerFile)
+			// Use the generated header as an order only dep to ensure that it is up to date when needed.
+			info.protoOrderOnlyDeps = append(info.protoOrderOnlyDeps, headerFile)
 		case ".aidl":
 			if aidlRule == nil {
 				aidlRule = android.NewRuleBuilder(pctx, ctx).Sbox(android.PathForModuleGen(ctx, "aidl"),
@@ -267,7 +296,12 @@ func genSources(ctx android.ModuleContext, srcFiles android.Paths,
 			cppFile := android.GenPathWithExt(ctx, "aidl", srcFile, "cpp")
 			depFile := android.GenPathWithExt(ctx, "aidl", srcFile, "cpp.d")
 			srcFiles[i] = cppFile
-			deps = append(deps, genAidl(ctx, aidlRule, srcFile, cppFile, depFile, buildFlags.aidlFlags)...)
+			aidlHeaders := genAidl(ctx, aidlRule, srcFile, cppFile, depFile, buildFlags.aidlFlags)
+			info.aidlHeaders = append(info.aidlHeaders, aidlHeaders...)
+			// Use the generated headers as order only deps to ensure that they are up to date when
+			// needed.
+			// TODO: Reduce the size of the ninja file by using one order only dep for the whole rule
+			info.aidlOrderOnlyDeps = append(info.aidlOrderOnlyDeps, aidlHeaders...)
 		case ".rscript", ".fs":
 			cppFile := rsGeneratedCppFile(ctx, srcFile)
 			rsFiles = append(rsFiles, srcFiles[i])
@@ -279,7 +313,10 @@ func genSources(ctx android.ModuleContext, srcFiles android.Paths,
 		case ".sysprop":
 			cppFile, headerFiles := genSysprop(ctx, srcFile)
 			srcFiles[i] = cppFile
-			deps = append(deps, headerFiles...)
+			info.syspropHeaders = append(info.syspropHeaders, headerFiles...)
+			// Use the generated headers as order only deps to ensure that they are up to date when
+			// needed.
+			info.syspropOrderOnlyDeps = append(info.syspropOrderOnlyDeps, headerFiles...)
 		}
 	}
 
@@ -291,9 +328,13 @@ func genSources(ctx android.ModuleContext, srcFiles android.Paths,
 		yaccRule_.Build("yacc", "gen yacc")
 	}
 
+	deps = append(deps, info.protoOrderOnlyDeps...)
+	deps = append(deps, info.aidlOrderOnlyDeps...)
+	deps = append(deps, info.syspropOrderOnlyDeps...)
+
 	if len(rsFiles) > 0 {
 		deps = append(deps, rsGenerateCpp(ctx, rsFiles, buildFlags.rsFlags)...)
 	}
 
-	return srcFiles, deps
+	return srcFiles, deps, info
 }

cc/library.go

@@ -1313,9 +1313,8 @@ func (library *libraryDecorator) link(ctx ModuleContext,
 			dir := android.PathForModuleGen(ctx, "aidl")
 			library.reexportDirs(dir)
 
-			// TODO: restrict to aidl deps
+			library.reexportDeps(library.baseCompiler.aidlOrderOnlyDeps...)
-			library.reexportDeps(library.baseCompiler.pathDeps...)
+			library.addExportedGeneratedHeaders(library.baseCompiler.aidlHeaders...)
-			library.addExportedGeneratedHeaders(library.baseCompiler.pathDeps...)
 		}
 	}
 
@@ -1329,9 +1328,8 @@ func (library *libraryDecorator) link(ctx ModuleContext,
 			includes = append(includes, flags.proto.Dir)
 			library.reexportDirs(includes...)
 
-			// TODO: restrict to proto deps
+			library.reexportDeps(library.baseCompiler.protoOrderOnlyDeps...)
-			library.reexportDeps(library.baseCompiler.pathDeps...)
+			library.addExportedGeneratedHeaders(library.baseCompiler.protoHeaders...)
-			library.addExportedGeneratedHeaders(library.baseCompiler.pathDeps...)
 		}
 	}
 
@@ -1352,8 +1350,8 @@ func (library *libraryDecorator) link(ctx ModuleContext,
 
 		// Add sysprop-related directories to the exported directories of this library.
 		library.reexportDirs(dir)
-		library.reexportDeps(library.baseCompiler.pathDeps...)
+		library.reexportDeps(library.baseCompiler.syspropOrderOnlyDeps...)
-		library.addExportedGeneratedHeaders(library.baseCompiler.pathDeps...)
+		library.addExportedGeneratedHeaders(library.baseCompiler.syspropHeaders...)
 	}
 
 	// Add stub-related flags if this library is a stub library.