Enable prebuilt hiddenapi CSV files.

By enabling these hiddenapi CSV files to be prebuilt, it
becomes possible to create a split build that supports
the hiddenapi encode dex step, but doesn't contain all
of the java sources needed to generate the CSV files.

Bug: 175048716
Test: m nothing
Test: new TestHiddenAPISingletonWithPrebuiltCsvFile
Test: local build without prebuilt hiddenapi
Test: local build with prebuilt hiddenapi
Change-Id: I805ea3ec05860d2df211a3985ec025bf36f0d775

1 files changed, 40 insertions, 0 deletions

diff --git a/java/hiddenapi_singleton.go b/java/hiddenapi_singleton.go
index d3025247b..4bd255cbf 100644
--- a/java/hiddenapi_singleton.go
+++ b/java/hiddenapi_singleton.go
@@ -67,6 +67,19 @@ func (h *hiddenAPISingleton) GenerateBuildActions(ctx android.SingletonContext)
 
 	stubFlagsRule(ctx)
 
+	// If there is a prebuilt hiddenapi dir, generate rules to use the
+	// files within. Generally, we build the hiddenapi files from source
+	// during the build, ensuring consistency. It's possible, in a split
+	// build (framework and vendor) scenario, for the vendor build to use
+	// prebuilt hiddenapi files from the framework build. In this scenario,
+	// the framework and vendor builds must use the same source to ensure
+	// consistency.
+
+	if ctx.Config().PrebuiltHiddenApiDir(ctx) != "" {
+		h.flags = prebuiltFlagsRule(ctx)
+		return
+	}
+
 	// These rules depend on files located in frameworks/base, skip them if running in a tree that doesn't have them.
 	if ctx.Config().FrameworksBaseDirExists(ctx) {
 		h.flags = flagsRule(ctx)
@@ -212,6 +225,19 @@ func stubFlagsRule(ctx android.SingletonContext) {
 	rule.Build("hiddenAPIStubFlagsFile", "hiddenapi stub flags")
 }
 
+func prebuiltFlagsRule(ctx android.SingletonContext) android.Path {
+	outputPath := hiddenAPISingletonPaths(ctx).flags
+	inputPath := android.PathForSource(ctx, ctx.Config().PrebuiltHiddenApiDir(ctx), "hiddenapi-flags.csv")
+
+	ctx.Build(pctx, android.BuildParams{
+		Rule:   android.Cp,
+		Output: outputPath,
+		Input:  inputPath,
+	})
+
+	return outputPath
+}
+
 // flagsRule creates a rule to build hiddenapi-flags.csv out of flags.csv files generated for boot image modules and
 // the unsupported API.
 func flagsRule(ctx android.SingletonContext) android.Path {
@@ -391,6 +417,20 @@ func (h *hiddenAPIIndexSingleton) GenerateBuildActions(ctx android.SingletonCont
 		return
 	}
 
+	if ctx.Config().PrebuiltHiddenApiDir(ctx) != "" {
+		outputPath := hiddenAPISingletonPaths(ctx).index
+		inputPath := android.PathForSource(ctx, ctx.Config().PrebuiltHiddenApiDir(ctx), "hiddenapi-index.csv")
+
+		ctx.Build(pctx, android.BuildParams{
+			Rule:   android.Cp,
+			Output: outputPath,
+			Input:  inputPath,
+		})
+
+		h.index = outputPath
+		return
+	}
+
 	indexes := android.Paths{}
 	ctx.VisitAllModules(func(module android.Module) {
 		if h, ok := module.(hiddenAPIIntf); ok {