Support release configs with only aconfig flags

Release configs with `aconfig_flags_only: true` can inherit build flag
values, but cannot set them.

Bug: 328495189
Test: manual
Change-Id: I2bdc88761d61fb20f10dc734f2ba87114f51b859

6 files changed, 83 insertions, 38 deletions

diff --git a/cmd/release_config/build_flag/main.go b/cmd/release_config/build_flag/main.go
index a8e632658..67edc3517 100644
--- a/cmd/release_config/build_flag/main.go
+++ b/cmd/release_config/build_flag/main.go
@@ -160,6 +160,9 @@ func SetCommand(configs *rc_lib.ReleaseConfigs, commonFlags Flags, cmd string, a
 	if err != nil {
 		return err
 	}
+	if release.AconfigFlagsOnly {
+		return fmt.Errorf("%s does not allow build flag overrides", targetRelease)
+	}
 	flagArtifact, ok := release.FlagArtifacts[name]
 	if !ok {
 		return fmt.Errorf("Unknown build flag %s", name)
diff --git a/cmd/release_config/crunch_flags/main.go b/cmd/release_config/crunch_flags/main.go
index b67374abf..e107b9fbb 100644
--- a/cmd/release_config/crunch_flags/main.go
+++ b/cmd/release_config/crunch_flags/main.go
@@ -15,18 +15,29 @@ import (
 	"google.golang.org/protobuf/proto"
 )
 
-// When a flag declaration has an initial value that is a string, the default workflow is PREBUILT.
-// If the flag name starts with any of prefixes in manualFlagNamePrefixes, it is MANUAL.
-var manualFlagNamePrefixes []string = []string{
-	"RELEASE_ACONFIG_",
-	"RELEASE_PLATFORM_",
-}
+var (
+	// When a flag declaration has an initial value that is a string, the default workflow is PREBUILT.
+	// If the flag name starts with any of prefixes in manualFlagNamePrefixes, it is MANUAL.
+	manualFlagNamePrefixes []string = []string{
+		"RELEASE_ACONFIG_",
+		"RELEASE_PLATFORM_",
+	}
+
+	// Set `aconfig_flags_only: true` in these release configs.
+	aconfigFlagsOnlyConfigs map[string]bool = map[string]bool{
+		"trunk_food": true,
+	}
 
-var defaultFlagNamespace string = "android_UNKNOWN"
+	// Default namespace value.  This is intentionally invalid.
+	defaultFlagNamespace string = "android_UNKNOWN"
+
+	// What is the current name for "next".
+	nextName string = "ap3a"
+)
 
 func RenameNext(name string) string {
 	if name == "next" {
-		return "ap3a"
+		return nextName
 	}
 	return name
 }
@@ -205,6 +216,9 @@ func ProcessBuildConfigs(dir, name string, paths []string, releaseProto *rc_prot
 				fmt.Printf("%s: Unexpected value %s=%s\n", path, valName, valValue)
 			}
 			if flagValue != nil {
+				if releaseProto.AconfigFlagsOnly {
+					return fmt.Errorf("%s does not allow build flag overrides", RenameNext(name))
+				}
 				valPath := filepath.Join(dir, "flag_values", RenameNext(name), fmt.Sprintf("%s.textproto", valName))
 				err := WriteFile(valPath, flagValue)
 				if err != nil {
@@ -285,6 +299,9 @@ func ProcessReleaseConfigMap(dir string, descriptionMap map[string]string) error
 		releaseConfig := &rc_proto.ReleaseConfig{
 			Name: proto.String(RenameNext(name)),
 		}
+		if aconfigFlagsOnlyConfigs[name] {
+			releaseConfig.AconfigFlagsOnly = true
+		}
 		configFiles := config[configRegexp.SubexpIndex("files")]
 		files := strings.Split(strings.ReplaceAll(configFiles, "$(local_dir)", dir+"/"), " ")
 		configInherits := config[configRegexp.SubexpIndex("inherits")]
diff --git a/cmd/release_config/release_config_lib/release_config.go b/cmd/release_config/release_config_lib/release_config.go
index 5996c469c..e51ff08b2 100644
--- a/cmd/release_config/release_config_lib/release_config.go
+++ b/cmd/release_config/release_config_lib/release_config.go
@@ -62,6 +62,10 @@ type ReleaseConfig struct {
 	// The names of release configs that we inherit
 	InheritNames []string
 
+	// True if this release config only allows inheritance and aconfig flag
+	// overrides. Build flag value overrides are an error.
+	AconfigFlagsOnly bool
+
 	// Unmarshalled flag artifacts
 	FlagArtifacts FlagArtifacts
 
@@ -174,6 +178,9 @@ func (config *ReleaseConfig) GenerateReleaseConfig(configs *ReleaseConfigs) erro
 			})
 
 		myDirsMap[contrib.DeclarationIndex] = true
+		if config.AconfigFlagsOnly && len(contrib.FlagValues) > 0 {
+			return fmt.Errorf("%s does not allow build flag overrides", config.Name)
+		}
 		for _, value := range contrib.FlagValues {
 			name := *value.proto.Name
 			fa, ok := config.FlagArtifacts[name]
diff --git a/cmd/release_config/release_config_lib/release_configs.go b/cmd/release_config/release_config_lib/release_configs.go
index 6b4709107..e5fd99e7c 100644
--- a/cmd/release_config/release_config_lib/release_configs.go
+++ b/cmd/release_config/release_config_lib/release_configs.go
@@ -206,6 +206,9 @@ func (configs *ReleaseConfigs) LoadReleaseConfigMap(path string, ConfigDirIndex
 		if err2 != nil {
 			return err2
 		}
+		if releaseConfigContribution.proto.GetAconfigFlagsOnly() {
+			config.AconfigFlagsOnly = true
+		}
 		m.ReleaseConfigContributions[name] = releaseConfigContribution
 		config.Contributions = append(config.Contributions, releaseConfigContribution)
 		return nil
diff --git a/cmd/release_config/release_config_proto/build_flags_src.pb.go b/cmd/release_config/release_config_proto/build_flags_src.pb.go
index 8054bd9ea..dded97566 100644
--- a/cmd/release_config/release_config_proto/build_flags_src.pb.go
+++ b/cmd/release_config/release_config_proto/build_flags_src.pb.go
@@ -387,6 +387,8 @@ type ReleaseConfig struct {
 	// List of names of the aconfig_value_set soong module(s) for this
 	// contribution.
 	AconfigValueSets []string `protobuf:"bytes,3,rep,name=aconfig_value_sets,json=aconfigValueSets" json:"aconfig_value_sets,omitempty"`
+	// Only aconfig flags are allowed in this release config.
+	AconfigFlagsOnly *bool `protobuf:"varint,4,opt,name=aconfig_flags_only,json=aconfigFlagsOnly" json:"aconfig_flags_only,omitempty"`
 }
 
 func (x *ReleaseConfig) Reset() {
@@ -442,6 +444,13 @@ func (x *ReleaseConfig) GetAconfigValueSets() []string {
 	return nil
 }
 
+func (x *ReleaseConfig) GetAconfigFlagsOnly() bool {
+	if x != nil && x.AconfigFlagsOnly != nil {
+		return *x.AconfigFlagsOnly
+	}
+	return false
+}
+
 // Any aliases.  These are used for continuous integration builder config.
 type ReleaseAlias struct {
 	state         protoimpl.MessageState
@@ -609,36 +618,39 @@ var file_build_flags_src_proto_rawDesc = []byte{
 	0x67, 0x5f, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x2e, 0x76, 0x61, 0x6c, 0x75, 0x65, 0x52, 0x05, 0x76,
 	0x61, 0x6c, 0x75, 0x65, 0x12, 0x1b, 0x0a, 0x08, 0x72, 0x65, 0x64, 0x61, 0x63, 0x74, 0x65, 0x64,
 	0x18, 0xca, 0x01, 0x20, 0x01, 0x28, 0x08, 0x52, 0x08, 0x72, 0x65, 0x64, 0x61, 0x63, 0x74, 0x65,
-	0x64, 0x22, 0x6e, 0x0a, 0x0e, 0x72, 0x65, 0x6c, 0x65, 0x61, 0x73, 0x65, 0x5f, 0x63, 0x6f, 0x6e,
-	0x66, 0x69, 0x67, 0x12, 0x12, 0x0a, 0x04, 0x6e, 0x61, 0x6d, 0x65, 0x18, 0x01, 0x20, 0x01, 0x28,
-	0x09, 0x52, 0x04, 0x6e, 0x61, 0x6d, 0x65, 0x12, 0x1a, 0x0a, 0x08, 0x69, 0x6e, 0x68, 0x65, 0x72,
-	0x69, 0x74, 0x73, 0x18, 0x02, 0x20, 0x03, 0x28, 0x09, 0x52, 0x08, 0x69, 0x6e, 0x68, 0x65, 0x72,
-	0x69, 0x74, 0x73, 0x12, 0x2c, 0x0a, 0x12, 0x61, 0x63, 0x6f, 0x6e, 0x66, 0x69, 0x67, 0x5f, 0x76,
-	0x61, 0x6c, 0x75, 0x65, 0x5f, 0x73, 0x65, 0x74, 0x73, 0x18, 0x03, 0x20, 0x03, 0x28, 0x09, 0x52,
-	0x10, 0x61, 0x63, 0x6f, 0x6e, 0x66, 0x69, 0x67, 0x56, 0x61, 0x6c, 0x75, 0x65, 0x53, 0x65, 0x74,
-	0x73, 0x22, 0x3b, 0x0a, 0x0d, 0x72, 0x65, 0x6c, 0x65, 0x61, 0x73, 0x65, 0x5f, 0x61, 0x6c, 0x69,
-	0x61, 0x73, 0x12, 0x12, 0x0a, 0x04, 0x6e, 0x61, 0x6d, 0x65, 0x18, 0x01, 0x20, 0x01, 0x28, 0x09,
-	0x52, 0x04, 0x6e, 0x61, 0x6d, 0x65, 0x12, 0x16, 0x0a, 0x06, 0x74, 0x61, 0x72, 0x67, 0x65, 0x74,
-	0x18, 0x02, 0x20, 0x01, 0x28, 0x09, 0x52, 0x06, 0x74, 0x61, 0x72, 0x67, 0x65, 0x74, 0x22, 0xac,
-	0x01, 0x0a, 0x12, 0x72, 0x65, 0x6c, 0x65, 0x61, 0x73, 0x65, 0x5f, 0x63, 0x6f, 0x6e, 0x66, 0x69,
-	0x67, 0x5f, 0x6d, 0x61, 0x70, 0x12, 0x45, 0x0a, 0x07, 0x61, 0x6c, 0x69, 0x61, 0x73, 0x65, 0x73,
-	0x18, 0x01, 0x20, 0x03, 0x28, 0x0b, 0x32, 0x2b, 0x2e, 0x61, 0x6e, 0x64, 0x72, 0x6f, 0x69, 0x64,
-	0x2e, 0x72, 0x65, 0x6c, 0x65, 0x61, 0x73, 0x65, 0x5f, 0x63, 0x6f, 0x6e, 0x66, 0x69, 0x67, 0x5f,
-	0x70, 0x72, 0x6f, 0x74, 0x6f, 0x2e, 0x72, 0x65, 0x6c, 0x65, 0x61, 0x73, 0x65, 0x5f, 0x61, 0x6c,
-	0x69, 0x61, 0x73, 0x52, 0x07, 0x61, 0x6c, 0x69, 0x61, 0x73, 0x65, 0x73, 0x12, 0x20, 0x0a, 0x0b,
-	0x64, 0x65, 0x73, 0x63, 0x72, 0x69, 0x70, 0x74, 0x69, 0x6f, 0x6e, 0x18, 0x02, 0x20, 0x01, 0x28,
-	0x09, 0x52, 0x0b, 0x64, 0x65, 0x73, 0x63, 0x72, 0x69, 0x70, 0x74, 0x69, 0x6f, 0x6e, 0x12, 0x2d,
-	0x0a, 0x12, 0x64, 0x65, 0x66, 0x61, 0x75, 0x6c, 0x74, 0x5f, 0x63, 0x6f, 0x6e, 0x74, 0x61, 0x69,
-	0x6e, 0x65, 0x72, 0x73, 0x18, 0x03, 0x20, 0x03, 0x28, 0x09, 0x52, 0x11, 0x64, 0x65, 0x66, 0x61,
-	0x75, 0x6c, 0x74, 0x43, 0x6f, 0x6e, 0x74, 0x61, 0x69, 0x6e, 0x65, 0x72, 0x73, 0x2a, 0x4a, 0x0a,
-	0x08, 0x77, 0x6f, 0x72, 0x6b, 0x66, 0x6c, 0x6f, 0x77, 0x12, 0x18, 0x0a, 0x14, 0x55, 0x4e, 0x53,
-	0x50, 0x45, 0x43, 0x49, 0x46, 0x49, 0x45, 0x44, 0x5f, 0x77, 0x6f, 0x72, 0x6b, 0x66, 0x6c, 0x6f,
-	0x77, 0x10, 0x00, 0x12, 0x0a, 0x0a, 0x06, 0x4c, 0x41, 0x55, 0x4e, 0x43, 0x48, 0x10, 0x01, 0x12,
-	0x0c, 0x0a, 0x08, 0x50, 0x52, 0x45, 0x42, 0x55, 0x49, 0x4c, 0x54, 0x10, 0x02, 0x12, 0x0a, 0x0a,
-	0x06, 0x4d, 0x41, 0x4e, 0x55, 0x41, 0x4c, 0x10, 0x03, 0x42, 0x33, 0x5a, 0x31, 0x61, 0x6e, 0x64,
-	0x72, 0x6f, 0x69, 0x64, 0x2f, 0x73, 0x6f, 0x6f, 0x6e, 0x67, 0x2f, 0x72, 0x65, 0x6c, 0x65, 0x61,
-	0x73, 0x65, 0x5f, 0x63, 0x6f, 0x6e, 0x66, 0x69, 0x67, 0x2f, 0x72, 0x65, 0x6c, 0x65, 0x61, 0x73,
-	0x65, 0x5f, 0x63, 0x6f, 0x6e, 0x66, 0x69, 0x67, 0x5f, 0x70, 0x72, 0x6f, 0x74, 0x6f,
+	0x64, 0x22, 0x9c, 0x01, 0x0a, 0x0e, 0x72, 0x65, 0x6c, 0x65, 0x61, 0x73, 0x65, 0x5f, 0x63, 0x6f,
+	0x6e, 0x66, 0x69, 0x67, 0x12, 0x12, 0x0a, 0x04, 0x6e, 0x61, 0x6d, 0x65, 0x18, 0x01, 0x20, 0x01,
+	0x28, 0x09, 0x52, 0x04, 0x6e, 0x61, 0x6d, 0x65, 0x12, 0x1a, 0x0a, 0x08, 0x69, 0x6e, 0x68, 0x65,
+	0x72, 0x69, 0x74, 0x73, 0x18, 0x02, 0x20, 0x03, 0x28, 0x09, 0x52, 0x08, 0x69, 0x6e, 0x68, 0x65,
+	0x72, 0x69, 0x74, 0x73, 0x12, 0x2c, 0x0a, 0x12, 0x61, 0x63, 0x6f, 0x6e, 0x66, 0x69, 0x67, 0x5f,
+	0x76, 0x61, 0x6c, 0x75, 0x65, 0x5f, 0x73, 0x65, 0x74, 0x73, 0x18, 0x03, 0x20, 0x03, 0x28, 0x09,
+	0x52, 0x10, 0x61, 0x63, 0x6f, 0x6e, 0x66, 0x69, 0x67, 0x56, 0x61, 0x6c, 0x75, 0x65, 0x53, 0x65,
+	0x74, 0x73, 0x12, 0x2c, 0x0a, 0x12, 0x61, 0x63, 0x6f, 0x6e, 0x66, 0x69, 0x67, 0x5f, 0x66, 0x6c,
+	0x61, 0x67, 0x73, 0x5f, 0x6f, 0x6e, 0x6c, 0x79, 0x18, 0x04, 0x20, 0x01, 0x28, 0x08, 0x52, 0x10,
+	0x61, 0x63, 0x6f, 0x6e, 0x66, 0x69, 0x67, 0x46, 0x6c, 0x61, 0x67, 0x73, 0x4f, 0x6e, 0x6c, 0x79,
+	0x22, 0x3b, 0x0a, 0x0d, 0x72, 0x65, 0x6c, 0x65, 0x61, 0x73, 0x65, 0x5f, 0x61, 0x6c, 0x69, 0x61,
+	0x73, 0x12, 0x12, 0x0a, 0x04, 0x6e, 0x61, 0x6d, 0x65, 0x18, 0x01, 0x20, 0x01, 0x28, 0x09, 0x52,
+	0x04, 0x6e, 0x61, 0x6d, 0x65, 0x12, 0x16, 0x0a, 0x06, 0x74, 0x61, 0x72, 0x67, 0x65, 0x74, 0x18,
+	0x02, 0x20, 0x01, 0x28, 0x09, 0x52, 0x06, 0x74, 0x61, 0x72, 0x67, 0x65, 0x74, 0x22, 0xac, 0x01,
+	0x0a, 0x12, 0x72, 0x65, 0x6c, 0x65, 0x61, 0x73, 0x65, 0x5f, 0x63, 0x6f, 0x6e, 0x66, 0x69, 0x67,
+	0x5f, 0x6d, 0x61, 0x70, 0x12, 0x45, 0x0a, 0x07, 0x61, 0x6c, 0x69, 0x61, 0x73, 0x65, 0x73, 0x18,
+	0x01, 0x20, 0x03, 0x28, 0x0b, 0x32, 0x2b, 0x2e, 0x61, 0x6e, 0x64, 0x72, 0x6f, 0x69, 0x64, 0x2e,
+	0x72, 0x65, 0x6c, 0x65, 0x61, 0x73, 0x65, 0x5f, 0x63, 0x6f, 0x6e, 0x66, 0x69, 0x67, 0x5f, 0x70,
+	0x72, 0x6f, 0x74, 0x6f, 0x2e, 0x72, 0x65, 0x6c, 0x65, 0x61, 0x73, 0x65, 0x5f, 0x61, 0x6c, 0x69,
+	0x61, 0x73, 0x52, 0x07, 0x61, 0x6c, 0x69, 0x61, 0x73, 0x65, 0x73, 0x12, 0x20, 0x0a, 0x0b, 0x64,
+	0x65, 0x73, 0x63, 0x72, 0x69, 0x70, 0x74, 0x69, 0x6f, 0x6e, 0x18, 0x02, 0x20, 0x01, 0x28, 0x09,
+	0x52, 0x0b, 0x64, 0x65, 0x73, 0x63, 0x72, 0x69, 0x70, 0x74, 0x69, 0x6f, 0x6e, 0x12, 0x2d, 0x0a,
+	0x12, 0x64, 0x65, 0x66, 0x61, 0x75, 0x6c, 0x74, 0x5f, 0x63, 0x6f, 0x6e, 0x74, 0x61, 0x69, 0x6e,
+	0x65, 0x72, 0x73, 0x18, 0x03, 0x20, 0x03, 0x28, 0x09, 0x52, 0x11, 0x64, 0x65, 0x66, 0x61, 0x75,
+	0x6c, 0x74, 0x43, 0x6f, 0x6e, 0x74, 0x61, 0x69, 0x6e, 0x65, 0x72, 0x73, 0x2a, 0x4a, 0x0a, 0x08,
+	0x77, 0x6f, 0x72, 0x6b, 0x66, 0x6c, 0x6f, 0x77, 0x12, 0x18, 0x0a, 0x14, 0x55, 0x4e, 0x53, 0x50,
+	0x45, 0x43, 0x49, 0x46, 0x49, 0x45, 0x44, 0x5f, 0x77, 0x6f, 0x72, 0x6b, 0x66, 0x6c, 0x6f, 0x77,
+	0x10, 0x00, 0x12, 0x0a, 0x0a, 0x06, 0x4c, 0x41, 0x55, 0x4e, 0x43, 0x48, 0x10, 0x01, 0x12, 0x0c,
+	0x0a, 0x08, 0x50, 0x52, 0x45, 0x42, 0x55, 0x49, 0x4c, 0x54, 0x10, 0x02, 0x12, 0x0a, 0x0a, 0x06,
+	0x4d, 0x41, 0x4e, 0x55, 0x41, 0x4c, 0x10, 0x03, 0x42, 0x33, 0x5a, 0x31, 0x61, 0x6e, 0x64, 0x72,
+	0x6f, 0x69, 0x64, 0x2f, 0x73, 0x6f, 0x6f, 0x6e, 0x67, 0x2f, 0x72, 0x65, 0x6c, 0x65, 0x61, 0x73,
+	0x65, 0x5f, 0x63, 0x6f, 0x6e, 0x66, 0x69, 0x67, 0x2f, 0x72, 0x65, 0x6c, 0x65, 0x61, 0x73, 0x65,
+	0x5f, 0x63, 0x6f, 0x6e, 0x66, 0x69, 0x67, 0x5f, 0x70, 0x72, 0x6f, 0x74, 0x6f,
 }
 
 var (
diff --git a/cmd/release_config/release_config_proto/build_flags_src.proto b/cmd/release_config/release_config_proto/build_flags_src.proto
index 017e5d400..0ef1a5ffa 100644
--- a/cmd/release_config/release_config_proto/build_flags_src.proto
+++ b/cmd/release_config/release_config_proto/build_flags_src.proto
@@ -119,6 +119,9 @@ message release_config {
   // List of names of the aconfig_value_set soong module(s) for this
   // contribution.
   repeated string aconfig_value_sets = 3;
+
+  // Only aconfig flags are allowed in this release config.
+  optional bool aconfig_flags_only = 4;
 }
 
 // Any aliases.  These are used for continuous integration builder config.