Notice support for APEX

Notice file for an APEX is created by merging notice files for the
modules included in it (plus the notice file for the APEX itself if
specified).

Notice files having the same content are not duplicated; it is emitted
only once.

Bug: 128701495
Test: m (apex_test is amended)
Test: m and inspect $(PRODUCT_OUT)/obj/NOTICE.txt to check there are
license entries for /system/apex/*.apex files

Change-Id: I169d91038291a6c71615de97cf5b03174afab5d4

5 files changed, 123 insertions, 5 deletions

diff --git a/android/androidmk.go b/android/androidmk.go
index fc34471cc..bd49e4c6f 100644
--- a/android/androidmk.go
+++ b/android/androidmk.go
@@ -319,7 +319,7 @@ func translateAndroidModule(ctx SingletonContext, w io.Writer, mod blueprint.Mod
 		}
 	}
 
-	if amod.noticeFile != nil {
+	if amod.noticeFile.Valid() {
 		fmt.Fprintln(&data.preamble, "LOCAL_NOTICE_FILE :=", amod.noticeFile.String())
 	}
 
diff --git a/android/module.go b/android/module.go
index afd2b714f..abf2cae43 100644
--- a/android/module.go
+++ b/android/module.go
@@ -189,6 +189,7 @@ type Module interface {
 	InstallInRecovery() bool
 	SkipInstall()
 	ExportedToMake() bool
+	NoticeFile() OptionalPath
 
 	AddProperties(props ...interface{})
 	GetProperties() []interface{}
@@ -466,7 +467,7 @@ type ModuleBase struct {
 	noAddressSanitizer bool
 	installFiles       Paths
 	checkbuildFiles    Paths
-	noticeFile         Path
+	noticeFile         OptionalPath
 
 	// Used by buildTargetSingleton to create checkbuild and per-directory build targets
 	// Only set on the final variant of each module
@@ -667,6 +668,10 @@ func (a *ModuleBase) Owner() string {
 	return String(a.commonProperties.Owner)
 }
 
+func (a *ModuleBase) NoticeFile() OptionalPath {
+	return a.noticeFile
+}
+
 func (a *ModuleBase) generateModuleTarget(ctx ModuleContext) {
 	allInstalledFiles := Paths{}
 	allCheckbuildFiles := Paths{}
@@ -852,9 +857,12 @@ func (a *ModuleBase) GenerateBuildActions(blueprintCtx blueprint.ModuleContext)
 		a.installFiles = append(a.installFiles, ctx.installFiles...)
 		a.checkbuildFiles = append(a.checkbuildFiles, ctx.checkbuildFiles...)
 
-		if a.commonProperties.Notice != nil {
-			// For filegroup-based notice file references.
-			a.noticeFile = PathForModuleSrc(ctx, *a.commonProperties.Notice)
+		notice := proptools.StringDefault(a.commonProperties.Notice, "NOTICE")
+		if m := SrcIsModule(notice); m != "" {
+			a.noticeFile = ctx.ExpandOptionalSource(&notice, "notice")
+		} else {
+			noticePath := filepath.Join(ctx.ModuleDir(), notice)
+			a.noticeFile = ExistentPathForSource(ctx, noticePath)
 		}
 	}
 
diff --git a/apex/apex.go b/apex/apex.go
index ad1ef74f7..c1f52a603 100644
--- a/apex/apex.go
+++ b/apex/apex.go
@@ -90,6 +90,12 @@ var (
 		CommandDeps: []string{"${zip2zip}"},
 		Description: "app bundle",
 	}, "abi")
+
+	apexMergeNoticeRule = pctx.StaticRule("apexMergeNoticeRule", blueprint.RuleParams{
+		Command:     `${mergenotice} --output $out $inputs`,
+		CommandDeps: []string{"${mergenotice}"},
+		Description: "merge notice files into $out",
+	}, "inputs")
 )
 
 var imageApexSuffix = ".apex"
@@ -138,6 +144,8 @@ func init() {
 	pctx.HostBinToolVariable("zip2zip", "zip2zip")
 	pctx.HostBinToolVariable("zipalign", "zipalign")
 
+	pctx.SourcePathVariable("mergenotice", "build/soong/scripts/mergenotice.py")
+
 	android.RegisterModuleType("apex", apexBundleFactory)
 	android.RegisterModuleType("apex_test", testApexBundleFactory)
 	android.RegisterModuleType("apex_defaults", defaultsFactory)
@@ -394,6 +402,8 @@ type apexBundle struct {
 	container_certificate_file android.Path
 	container_private_key_file android.Path
 
+	mergedNoticeFile android.WritablePath
+
 	// list of files to be included in this apex
 	filesInfo []apexFile
 
@@ -814,6 +824,8 @@ func (a *apexBundle) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 	a.installDir = android.PathForModuleInstall(ctx, "apex")
 	a.filesInfo = filesInfo
 
+	a.buildNoticeFile(ctx)
+
 	if a.apexTypes.zip() {
 		a.buildUnflattenedApex(ctx, zipApex)
 	}
@@ -827,6 +839,37 @@ func (a *apexBundle) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 	}
 }
 
+func (a *apexBundle) buildNoticeFile(ctx android.ModuleContext) {
+	noticeFiles := []android.Path{}
+	noticeFilesString := []string{}
+	for _, f := range a.filesInfo {
+		if f.module != nil {
+			notice := f.module.NoticeFile()
+			if notice.Valid() {
+				noticeFiles = append(noticeFiles, notice.Path())
+				noticeFilesString = append(noticeFilesString, notice.Path().String())
+			}
+		}
+	}
+	// append the notice file specified in the apex module itself
+	if a.NoticeFile().Valid() {
+		noticeFiles = append(noticeFiles, a.NoticeFile().Path())
+		noticeFilesString = append(noticeFilesString, a.NoticeFile().Path().String())
+	}
+
+	if len(noticeFiles) > 0 {
+		a.mergedNoticeFile = android.PathForModuleOut(ctx, "NOTICE")
+		ctx.Build(pctx, android.BuildParams{
+			Rule:   apexMergeNoticeRule,
+			Inputs: noticeFiles,
+			Output: a.mergedNoticeFile,
+			Args: map[string]string{
+				"inputs": strings.Join(noticeFilesString, " "),
+			},
+		})
+	}
+}
+
 func (a *apexBundle) buildUnflattenedApex(ctx android.ModuleContext, apexType apexPackaging) {
 	cert := String(a.properties.Certificate)
 	if cert != "" && android.SrcIsModule(cert) == "" {
@@ -1078,6 +1121,10 @@ func (a *apexBundle) androidMkForFiles(w io.Writer, name, moduleDir string, apex
 			if len(fi.symlinks) > 0 {
 				fmt.Fprintln(w, "LOCAL_MODULE_SYMLINKS :=", strings.Join(fi.symlinks, " "))
 			}
+
+			if fi.module != nil && fi.module.NoticeFile().Valid() {
+				fmt.Fprintln(w, "LOCAL_NOTICE_FILE :=", fi.module.NoticeFile().Path().String())
+			}
 		} else {
 			fmt.Fprintln(w, "LOCAL_MODULE_PATH :=", pathWhenActivated)
 		}
@@ -1168,6 +1215,9 @@ func (a *apexBundle) androidMkForType(apexType apexPackaging) android.AndroidMkD
 				fmt.Fprintln(w, "LOCAL_MODULE_STEM :=", name+apexType.suffix())
 				fmt.Fprintln(w, "LOCAL_UNINSTALLABLE_MODULE :=", !a.installable())
 				fmt.Fprintln(w, "LOCAL_REQUIRED_MODULES :=", String(a.properties.Key))
+				if a.installable() && a.mergedNoticeFile != nil {
+					fmt.Fprintln(w, "LOCAL_NOTICE_FILE :=", a.mergedNoticeFile.String())
+				}
 				if len(moduleNames) > 0 {
 					fmt.Fprintln(w, "LOCAL_REQUIRED_MODULES +=", strings.Join(moduleNames, " "))
 				}
diff --git a/apex/apex_test.go b/apex/apex_test.go
index f221cf228..ac2701f7e 100644
--- a/apex/apex_test.go
+++ b/apex/apex_test.go
@@ -159,6 +159,8 @@ func testApex(t *testing.T, bp string) *android.TestContext {
 		"testkey.override.pk8":                 nil,
 		"vendor/foo/devkeys/testkey.avbpubkey": nil,
 		"vendor/foo/devkeys/testkey.pem":       nil,
+		"NOTICE":                               nil,
+		"custom_notice":                        nil,
 	})
 	_, errs := ctx.ParseFileList(".", []string{"Android.bp"})
 	android.FailIfErrored(t, errs)
@@ -280,6 +282,7 @@ func TestBasicApex(t *testing.T) {
 			srcs: ["mylib.cpp"],
 			system_shared_libs: [],
 			stl: "none",
+			notice: "custom_notice",
 		}
 	`)
 
@@ -319,6 +322,14 @@ func TestBasicApex(t *testing.T) {
 	if !good {
 		t.Errorf("Could not find all expected symlinks! foo: %t, foo_link_64: %t. Command was %s", found_foo, found_foo_link_64, copyCmds)
 	}
+
+	apexMergeNoticeRule := ctx.ModuleForTests("myapex", "android_common_myapex").Rule("apexMergeNoticeRule")
+	noticeInputs := strings.Split(apexMergeNoticeRule.Args["inputs"], " ")
+	if len(noticeInputs) != 3 {
+		t.Errorf("number of input notice files: expected = 3, actual = %d", len(noticeInputs))
+	}
+	ensureListContains(t, noticeInputs, "NOTICE")
+	ensureListContains(t, noticeInputs, "custom_notice")
 }
 
 func TestBasicZipApex(t *testing.T) {
diff --git a/scripts/mergenotice.py b/scripts/mergenotice.py
new file mode 100755
index 000000000..407ae8cc4
--- /dev/null
+++ b/scripts/mergenotice.py
@@ -0,0 +1,49 @@
+#!/usr/bin/env python
+#
+# 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.
+#
+"""
+Merges input notice files to the output file while ignoring duplicated files
+This script shouldn't be confused with build/make/tools/generate-notice-files.py
+which is responsible for creating the final notice file for all artifacts
+installed. This script has rather limited scope; it is meant to create a merged
+notice file for a set of modules that are packaged together, e.g. in an APEX.
+The merged notice file does not reveal the individual files in the package.
+"""
+
+import sys
+import argparse
+
+def get_args():
+  parser = argparse.ArgumentParser(description='Merge notice files.')
+  parser.add_argument('--output', help='output file path.')
+  parser.add_argument('inputs', metavar='INPUT', nargs='+',
+                      help='input notice file')
+  return parser.parse_args()
+
+def main(argv):
+  args = get_args()
+
+  processed = set()
+  with open(args.output, 'w+') as output:
+    for input in args.inputs:
+      with open(input, 'r') as f:
+        data = f.read().strip()
+        if data not in processed:
+          processed.add(data)
+          output.write('%s\n\n' % data)
+
+if __name__ == '__main__':
+  main(sys.argv)