Snap for 7390572 from 23ac240b8f18bd5a6f336131ffa04a44509bcc2e to sc-d2-release

Change-Id: Iec334c6e7ff59f88acb3b31c9a7182c56a03cb1f

3 files changed, 80 insertions, 47 deletions

diff --git a/build/Android.mk b/build/Android.mk
deleted file mode 100644
index e50f7028..00000000
--- a/build/Android.mk
+++ /dev/null
@@ -1,18 +0,0 @@
-#
-# Copyright (C) 2019 The Android Open Source Project
-#
-# 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.
-#
-
-.PHONY: aidl-freeze-api
-aidl-freeze-api: $(addsuffix -freeze-api, $(SOONG_ALL_AIDL_INTERFACES))
diff --git a/build/aidl_api.go b/build/aidl_api.go
index 3ce72ae1..02290412 100644
--- a/build/aidl_api.go
+++ b/build/aidl_api.go
@@ -148,28 +148,64 @@ func (m *aidlApi) createApiDumpFromSource(ctx android.ModuleContext) apiDump {
 	return apiDump{apiDir, apiFiles.Paths(), android.OptionalPathForPath(hashFile)}
 }
 
-func (m *aidlApi) makeApiDumpAsVersion(ctx android.ModuleContext, dump apiDump, version string) android.WritablePath {
-	timestampFile := android.PathForModuleOut(ctx, "updateapi_"+version+".timestamp")
+func (m *aidlApi) makeApiDumpAsVersion(ctx android.ModuleContext, dump apiDump, version string, latestVersionDump *apiDump) android.WritablePath {
+	creatingNewVersion := version != currentVersion
+	moduleDir := android.PathForModuleSrc(ctx).String()
+	targetDir := filepath.Join(moduleDir, m.apiDir(), version)
+	rb := android.NewRuleBuilder(pctx, ctx)
 
-	modulePath := android.PathForModuleSrc(ctx).String()
+	if creatingNewVersion {
+		// We are asked to create a new version. But before doing that, check if the given
+		// dump is the same as the latest version. If so, don't create a new version,
+		// otherwise we will be unnecessarily creating many versions. `newVersionNeededFile`
+		// is created when the equality check fails.
+		newVersionNeededFile := android.PathForModuleOut(ctx, "updateapi_"+version+".needed")
+		rb.Command().Text("rm -f " + newVersionNeededFile.String())
+
+		if latestVersionDump != nil {
+			equalityCheckCommand := rb.Command()
+			equalityCheckCommand.BuiltTool("aidl").
+				FlagWithArg("--checkapi=", "equal")
+			if m.properties.Stability != nil {
+				equalityCheckCommand.FlagWithArg("--stability ", *m.properties.Stability)
+			}
+			equalityCheckCommand.
+				Text(latestVersionDump.dir.String()).Implicits(latestVersionDump.files).
+				Text(dump.dir.String()).Implicits(dump.files).
+				Text("&> /dev/null")
+			equalityCheckCommand.
+				Text("|| touch").
+				Text(newVersionNeededFile.String())
+		} else {
+			// If there is no latest version (i.e. we are creating the initial version)
+			// create the new version unconditionally
+			rb.Command().Text("touch").Text(newVersionNeededFile.String())
+		}
 
-	targetDir := filepath.Join(modulePath, m.apiDir(), version)
-	rb := android.NewRuleBuilder(pctx, ctx)
-	// Wipe the target directory and then copy the API dump into the directory
-	rb.Command().Text("mkdir -p " + targetDir)
-	rb.Command().Text("rm -rf " + targetDir + "/*")
-	if version != currentVersion {
-		rb.Command().Text("cp -rf " + dump.dir.String() + "/. " + targetDir).Implicits(dump.files)
-		// If this is making a new frozen (i.e. non-current) version of the interface,
-		// modify Android.bp file to add the new version to the 'versions' property.
-		rb.Command().BuiltTool("bpmodify").
+		// Copy the given dump to the target directory only when the equality check failed
+		// (i.e. `newVersionNeededFile` exists).
+		rb.Command().
+			Text("if [ -f " + newVersionNeededFile.String() + " ]; then").
+			Text("cp -rf " + dump.dir.String() + "/. " + targetDir).Implicits(dump.files).
+			Text("; fi")
+
+		// Also modify Android.bp file to add the new version to the 'versions' property.
+		rb.Command().
+			Text("if [ -f " + newVersionNeededFile.String() + " ]; then").
+			BuiltTool("bpmodify").
 			Text("-w -m " + m.properties.BaseName).
 			Text("-parameter versions -a " + version).
-			Text(android.PathForModuleSrc(ctx, "Android.bp").String())
+			Text(android.PathForModuleSrc(ctx, "Android.bp").String()).
+			Text("; fi")
+
 	} else {
-		// In this case (unfrozen interface), don't copy .hash
+		// We are updating the current version. Don't copy .hash to the current dump
+		rb.Command().Text("mkdir -p " + targetDir)
+		rb.Command().Text("rm -rf " + targetDir + "/*")
 		rb.Command().Text("cp -rf " + dump.dir.String() + "/* " + targetDir).Implicits(dump.files)
 	}
+
+	timestampFile := android.PathForModuleOut(ctx, "updateapi_"+version+".timestamp")
 	rb.Command().Text("touch").Output(timestampFile)
 
 	rb.Build("dump_aidl_api"+m.properties.BaseName+"_"+version,
@@ -311,6 +347,10 @@ func (m *aidlApi) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 			ctx.ModuleErrorf("API version %s path %s does not exist", ver, apiDir)
 		}
 	}
+	var latestVersionDump *apiDump
+	if len(dumps) >= 1 {
+		latestVersionDump = &dumps[len(dumps)-1]
+	}
 	if currentApiDir.Valid() {
 		dumps = append(dumps, currentApiDump)
 	}
@@ -328,11 +368,11 @@ func (m *aidlApi) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 	}
 
 	// API dump from source is updated to the 'current' version. Triggered by `m <name>-update-api`
-	m.updateApiTimestamp = m.makeApiDumpAsVersion(ctx, totApiDump, currentVersion)
+	m.updateApiTimestamp = m.makeApiDumpAsVersion(ctx, totApiDump, currentVersion, nil)
 
 	// API dump from source is frozen as the next stable version. Triggered by `m <name>-freeze-api`
 	nextVersion := m.nextVersion()
-	m.freezeApiTimestamp = m.makeApiDumpAsVersion(ctx, totApiDump, nextVersion)
+	m.freezeApiTimestamp = m.makeApiDumpAsVersion(ctx, totApiDump, nextVersion, latestVersionDump)
 }
 
 func (m *aidlApi) AndroidMk() android.AndroidMkData {
@@ -377,3 +417,26 @@ func addApiModule(mctx android.LoadHookContext, i *aidlInterface) string {
 	})
 	return apiModule
 }
+
+func init() {
+	android.RegisterSingletonType("aidl-freeze-api", freezeApiSingletonFactory)
+}
+
+func freezeApiSingletonFactory() android.Singleton {
+	return &freezeApiSingleton{}
+}
+
+type freezeApiSingleton struct{}
+
+func (f *freezeApiSingleton) GenerateBuildActions(ctx android.SingletonContext) {
+	var files android.Paths
+	ctx.VisitAllModules(func(module android.Module) {
+		if !module.Enabled() {
+			return
+		}
+		if m, ok := module.(*aidlApi); ok {
+			files = append(files, m.freezeApiTimestamp)
+		}
+	})
+	ctx.Phony("aidl-freeze-api", files...)
+}
diff --git a/build/aidl_mapping.go b/build/aidl_mapping.go
index b48e61e6..b9194955 100644
--- a/build/aidl_mapping.go
+++ b/build/aidl_mapping.go
@@ -19,7 +19,6 @@ import (
 
 	"fmt"
 	"io"
-	"strings"
 
 	"github.com/google/blueprint"
 )
@@ -35,7 +34,6 @@ var (
 
 func init() {
 	android.RegisterModuleType("aidl_mapping", aidlMappingFactory)
-	android.RegisterMakeVarsProvider(pctx, allAidlInterfacesMakeVars)
 }
 
 type aidlMappingProperties struct {
@@ -90,13 +88,3 @@ func (m *aidlMapping) AndroidMk() android.AndroidMkData {
 		},
 	}
 }
-
-func allAidlInterfacesMakeVars(ctx android.MakeVarsContext) {
-	names := []string{}
-	ctx.VisitAllModules(func(module android.Module) {
-		if ai, ok := module.(*aidlInterface); ok {
-			names = append(names, ai.BaseModuleName())
-		}
-	})
-	ctx.Strict("ALL_AIDL_INTERFACES", strings.Join(names, " "))
-}