Prototype changes for multitree
This change contains a prototype implementation for multitree. Several
interfaces and modules are added.
1. Imported/Exported
Modules implementing Exportable interface can export artifacts to other
components. "imported_filegroup" modules can import generated artifacts from other exported modules.
2. Multitree metadata
It contains information about imported/exported modules in each
component, and can be generated via "m update-meta".
3. cc library stub
It's based on prototype stub libraries. It uses imported/exported
mechanism to expose a C API, with a map.txt file and header files.
Bug: 230448564
Test: m
Change-Id: Id7ff7618e2c630c5617a564d8b23b60a1cc9c8e8
diff --git a/multitree/export.go b/multitree/export.go
new file mode 100644
index 0000000..aecade5
--- /dev/null
+++ b/multitree/export.go
@@ -0,0 +1,67 @@
+// Copyright 2022 Google Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package multitree
+
+import (
+ "android/soong/android"
+
+ "github.com/google/blueprint/proptools"
+)
+
+type moduleExportProperty struct {
+ // True if the module is exported to the other components in a multi-tree.
+ // Any components in the multi-tree can import this module to use.
+ Export *bool
+}
+
+type ExportableModuleBase struct {
+ properties moduleExportProperty
+}
+
+type Exportable interface {
+ // Properties for the exporable module.
+ exportableModuleProps() *moduleExportProperty
+
+ // Check if this module can be exported.
+ // If this returns false, the module will not be exported regardless of the 'export' value.
+ Exportable() bool
+
+ // Returns 'true' if this module has 'export: true'
+ // This module will not be exported if it returns 'false' to 'Exportable()' interface even if
+ // it has 'export: true'.
+ IsExported() bool
+
+ // Map from tags to outputs.
+ // Each module can tag their outputs for convenience.
+ TaggedOutputs() map[string]android.Paths
+}
+
+type ExportableModule interface {
+ android.Module
+ android.OutputFileProducer
+ Exportable
+}
+
+func InitExportableModule(module ExportableModule) {
+ module.AddProperties(module.exportableModuleProps())
+}
+
+func (m *ExportableModuleBase) exportableModuleProps() *moduleExportProperty {
+ return &m.properties
+}
+
+func (m *ExportableModuleBase) IsExported() bool {
+ return proptools.Bool(m.properties.Export)
+}