Soong: BPF: add defaults support and local include

Add support for defaults clause in the bpf soong module, as well as
local_include_dirs property.

Test: TH
Change-Id: Iaa03e7f1f6dcf0e929d1d5b23bb79ca2a8366bef
Signed-off-by: Neill Kapron <nkapron@google.com>

bpf/bpf.go

@@ -56,6 +56,7 @@ var (
 )
 
 func registerBpfBuildComponents(ctx android.RegistrationContext) {
+	ctx.RegisterModuleType("bpf_defaults", defaultsFactory)
 	ctx.RegisterModuleType("bpf", BpfFactory)
 }
 
@@ -77,10 +78,16 @@ type BpfProperties struct {
 	// the C/C++ module.
 	Cflags []string
 
-	// directories (relative to the root of the source tree) that will
+	// list of directories relative to the root of the source tree that
-	// be added to the include paths using -I.
+	// will be added to the include paths using -I.
+	// If possible, don't use this. If adding paths from the current
+	// directory, use local_include_dirs. If adding paths from other
+	// modules, use export_include_dirs in that module.
 	Include_dirs []string
 
+	// list of directories relative to the Blueprint file that will be
+	// added to the include path using -I.
+	Local_include_dirs []string
 	// optional subdirectory under which this module is installed into.
 	Sub_dir string
 
@@ -94,7 +101,7 @@ type BpfProperties struct {
 
 type bpf struct {
 	android.ModuleBase
-
+	android.DefaultableModuleBase
 	properties BpfProperties
 
 	objs android.Paths
@@ -163,6 +170,10 @@ func (bpf *bpf) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 		"-I " + ctx.ModuleDir(),
 	}
 
+	for _, dir := range android.PathsForModuleSrc(ctx, bpf.properties.Local_include_dirs) {
+		cflags = append(cflags, "-I "+dir.String())
+	}
+
 	for _, dir := range android.PathsForSource(ctx, bpf.properties.Include_dirs) {
 		cflags = append(cflags, "-I "+dir.String())
 	}
@@ -264,6 +275,26 @@ func (bpf *bpf) AndroidMk() android.AndroidMkData {
 	}
 }
 
+type Defaults struct {
+	android.ModuleBase
+	android.DefaultsModuleBase
+}
+
+func defaultsFactory() android.Module {
+	return DefaultsFactory()
+}
+
+func DefaultsFactory(props ...interface{}) android.Module {
+	module := &Defaults{}
+
+	module.AddProperties(props...)
+	module.AddProperties(&BpfProperties{})
+
+	android.InitDefaultsModule(module)
+
+	return module
+}
+
 func (bpf *bpf) SubDir() string {
 	return bpf.properties.Sub_dir
 }
@@ -274,5 +305,7 @@ func BpfFactory() android.Module {
 	module.AddProperties(&module.properties)
 
 	android.InitAndroidArchModule(module, android.DeviceSupported, android.MultilibCommon)
+	android.InitDefaultableModule(module)
+
 	return module
 }