Support for prebuilt_avb in Soong

Generally, the `root` directories for `prebuilt_etc` and
`prebuilt_root` are <partitions>. And <partitions> default to false
for InstallInRoot(), they always create a "system" subdirectory.
(See android/paths.go:modulePartition())

However, avb keys like `q-developer-gsi.avbpubkey` are installed by
default in the `avb` subdirectory under the `root directory` of the
<partition>. Therefore, it is necessary to create `prebuilt_avb` in
Soong and force the installation directory to be the `avb` subdirectory
under the `root directory` of the <partition> to meet the requirements.

Bug: 347636127
Test: go test -run TestPrebuiltAvbInstallDirPath
Change-Id: I0ee08492da9a96a567700a7285c527b280dcd5db

etc/prebuilt_etc.go

@@ -50,6 +50,7 @@ func RegisterPrebuiltEtcBuildComponents(ctx android.RegistrationContext) {
 	ctx.RegisterModuleType("prebuilt_etc", PrebuiltEtcFactory)
 	ctx.RegisterModuleType("prebuilt_etc_host", PrebuiltEtcHostFactory)
 	ctx.RegisterModuleType("prebuilt_etc_cacerts", PrebuiltEtcCaCertsFactory)
+	ctx.RegisterModuleType("prebuilt_avb", PrebuiltAvbFactory)
 	ctx.RegisterModuleType("prebuilt_root", PrebuiltRootFactory)
 	ctx.RegisterModuleType("prebuilt_root_host", PrebuiltRootHostFactory)
 	ctx.RegisterModuleType("prebuilt_usr_share", PrebuiltUserShareFactory)
@@ -155,6 +156,9 @@ type PrebuiltEtc struct {
 	additionalDependencies *android.Paths
 
 	usedSrcsProperty bool
+	// installInRoot is used to return the value of the InstallInRoot() method. The default value is false.
+	// Currently, only prebuilt_avb can be set to true.
+	installInRoot bool
 
 	makeClass string
 }
@@ -241,6 +245,10 @@ func (p *PrebuiltEtc) DebugRamdiskVariantNeeded(ctx android.BaseModuleContext) b
 	return proptools.Bool(p.properties.Debug_ramdisk_available) || p.ModuleBase.InstallInDebugRamdisk()
 }
 
+func (p *PrebuiltEtc) InstallInRoot() bool {
+	return p.installInRoot
+}
+
 func (p *PrebuiltEtc) RecoveryVariantNeeded(ctx android.BaseModuleContext) bool {
 	return proptools.Bool(p.properties.Recovery_available) || p.ModuleBase.InstallInRecovery()
 }
@@ -494,12 +502,20 @@ func (p *PrebuiltEtc) AndroidModuleBase() *android.ModuleBase {
 
 func InitPrebuiltEtcModule(p *PrebuiltEtc, dirBase string) {
 	p.installDirBase = dirBase
+	p.installInRoot = false
 	p.AddProperties(&p.properties)
 	p.AddProperties(&p.subdirProperties)
 }
 
 func InitPrebuiltRootModule(p *PrebuiltEtc) {
 	p.installDirBase = "."
+	p.installInRoot = false
+	p.AddProperties(&p.properties)
+}
+
+func InitPrebuiltAvbModule(p *PrebuiltEtc) {
+	p.installDirBase = "avb"
+	p.installInRoot = true
 	p.AddProperties(&p.properties)
 }
 
@@ -553,6 +569,20 @@ func PrebuiltEtcCaCertsFactory() android.Module {
 	return module
 }
 
+// Generally, a <partition> directory will contain a `system` subdirectory, but the <partition> of
+// `prebuilt_avb` will not have a `system` subdirectory.
+// Ultimately, prebuilt_avb will install the prebuilt artifact to the `avb` subdirectory under the
+// root directory of the partition: <partition_root>/avb.
+// prebuilt_avb does not allow adding any other subdirectories.
+func PrebuiltAvbFactory() android.Module {
+	module := &PrebuiltEtc{}
+	InitPrebuiltAvbModule(module)
+	// This module is device-only
+	android.InitAndroidArchModule(module, android.DeviceSupported, android.MultilibFirst)
+	android.InitDefaultableModule(module)
+	return module
+}
+
 // prebuilt_root is for a prebuilt artifact that is installed in
 // <partition>/ directory. Can't have any sub directories.
 func PrebuiltRootFactory() android.Module {

etc/prebuilt_etc_test.go

@@ -244,6 +244,31 @@ func TestPrebuiltRootInstallDirPathValidate(t *testing.T) {
 	`)
 }
 
+func TestPrebuiltAvbInstallDirPath(t *testing.T) {
+	result := prepareForPrebuiltEtcTest.RunTestWithBp(t, `
+		prebuilt_avb {
+			name: "foo.conf",
+			src: "foo.conf",
+			filename: "foo.conf",
+			//recovery: true,
+		}
+	`)
+
+	p := result.Module("foo.conf", "android_arm64_armv8-a").(*PrebuiltEtc)
+	expected := "out/soong/target/product/test_device/root/avb"
+	android.AssertPathRelativeToTopEquals(t, "install dir", expected, p.installDirPath)
+}
+
+func TestPrebuiltAvdInstallDirPathValidate(t *testing.T) {
+	prepareForPrebuiltEtcTest.ExtendWithErrorHandler(android.FixtureExpectsAtLeastOneErrorMatchingPattern("filename cannot contain separator")).RunTestWithBp(t, `
+		prebuilt_avb {
+			name: "foo.conf",
+			src: "foo.conf",
+			filename: "foo/bar.conf",
+		}
+	`)
+}
+
 func TestPrebuiltUserShareInstallDirPath(t *testing.T) {
 	result := prepareForPrebuiltEtcTest.RunTestWithBp(t, `
 		prebuilt_usr_share {