Initial prebuilt support
Support prebuilt shared libraries as an initial proof-of-concept of
prebuilts. Future changes will support binaries and static libraries,
and the ability to select which to use based on something besides
blueprint properties.
Test: TestPrebuilts run during m -j
Change-Id: I6e84da667e9005ae11844bad01d25cbe4ced1ce3
diff --git a/android/prebuilt.go b/android/prebuilt.go
new file mode 100644
index 0000000..fb9e515
--- /dev/null
+++ b/android/prebuilt.go
@@ -0,0 +1,121 @@
+// Copyright 2016 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 android
+
+import "github.com/google/blueprint"
+
+// This file implements common functionality for handling modules that may exist as prebuilts,
+// source, or both.
+
+var prebuiltDependencyTag blueprint.BaseDependencyTag
+
+func SourceModuleHasPrebuilt(ctx ModuleContext) OptionalPath {
+ var path Path
+ ctx.VisitDirectDeps(func(m blueprint.Module) {
+ if ctx.OtherModuleDependencyTag(m) == prebuiltDependencyTag {
+ p := m.(PrebuiltInterface).Prebuilt()
+ if p.usePrebuilt(ctx) {
+ path = p.Path(ctx)
+ }
+ }
+ })
+
+ return OptionalPathForPath(path)
+}
+
+type Prebuilt struct {
+ Properties struct {
+ Srcs []string `android:"arch_variant"`
+ // When prefer is set to true the prebuilt will be used instead of any source module with
+ // a matching name.
+ Prefer bool `android:"arch_variant"`
+
+ SourceExists bool `blueprint:"mutated"`
+ }
+ module Module
+}
+
+func (p *Prebuilt) Name(name string) string {
+ return "prebuilt_" + name
+}
+
+func (p *Prebuilt) Path(ctx ModuleContext) Path {
+ if len(p.Properties.Srcs) == 0 {
+ ctx.PropertyErrorf("srcs", "missing prebuilt source file")
+ return nil
+ }
+
+ if len(p.Properties.Srcs) > 1 {
+ ctx.PropertyErrorf("srcs", "multiple prebuilt source files")
+ return nil
+ }
+
+ return PathForModuleSrc(ctx, p.Properties.Srcs[0])
+}
+
+type PrebuiltInterface interface {
+ Module
+ Prebuilt() *Prebuilt
+}
+
+type PrebuiltSourceInterface interface {
+ SkipInstall()
+}
+
+// prebuiltMutator ensures that there is always a module with an undecorated name, and marks
+// prebuilt modules that have both a prebuilt and a source module.
+func prebuiltMutator(ctx BottomUpMutatorContext) {
+ if m, ok := ctx.Module().(PrebuiltInterface); ok && m.Prebuilt() != nil {
+ p := m.Prebuilt()
+ name := m.base().BaseModuleName()
+ if ctx.OtherModuleExists(name) {
+ ctx.AddReverseDependency(ctx.Module(), prebuiltDependencyTag, name)
+ p.Properties.SourceExists = true
+ } else {
+ ctx.Rename(name)
+ }
+ }
+}
+
+// PrebuiltReplaceMutator replaces dependencies on the source module with dependencies on the prebuilt
+// when both modules exist and the prebuilt should be used.
+func PrebuiltReplaceMutator(ctx BottomUpMutatorContext) {
+ if m, ok := ctx.Module().(PrebuiltInterface); ok && m.Prebuilt() != nil {
+ p := m.Prebuilt()
+ name := m.base().BaseModuleName()
+ if p.Properties.SourceExists && p.usePrebuilt(ctx) {
+ ctx.ReplaceDependencies(name)
+ }
+ }
+}
+
+// PrebuiltDisableMutator disables source modules that have prebuilts that should be used instead.
+func PrebuiltDisableMutator(ctx TopDownMutatorContext) {
+ if s, ok := ctx.Module().(PrebuiltSourceInterface); ok {
+ ctx.VisitDirectDeps(func(m blueprint.Module) {
+ if ctx.OtherModuleDependencyTag(m) == prebuiltDependencyTag {
+ p := m.(PrebuiltInterface).Prebuilt()
+ if p.usePrebuilt(ctx) {
+ s.SkipInstall()
+ }
+ }
+ })
+ }
+}
+
+func (p *Prebuilt) usePrebuilt(ctx BaseContext) bool {
+ // TODO: use p.Properties.Name and ctx.ModuleDir to override prefer
+ return p.Properties.Prefer && len(p.Properties.Srcs) > 0
+}