1 files changed, 267 insertions, 0 deletions
diff --git a/cmd/release_config/release_config_lib/release_config.go b/cmd/release_config/release_config_lib/release_config.go
new file mode 100644
index 000000000..f25cc6e66
--- /dev/null
+++ b/cmd/release_config/release_config_lib/release_config.go
@@ -0,0 +1,267 @@
+// Copyright 2024 Google Inc. All rights reserved.
+//
+// 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.
+
+package release_config_lib
+
+import (
+	"cmp"
+	"fmt"
+	"path/filepath"
+	"slices"
+	"sort"
+	"strings"
+
+	rc_proto "android/soong/cmd/release_config/release_config_proto"
+
+	"google.golang.org/protobuf/proto"
+)
+
+// One directory's contribution to the a release config.
+type ReleaseConfigContribution struct {
+	// Paths to files providing this config.
+	path string
+
+	// The index of the config directory where this release config
+	// contribution was declared.
+	// Flag values cannot be set in a location with a lower index.
+	DeclarationIndex int
+
+	// Protobufs relevant to the config.
+	proto rc_proto.ReleaseConfig
+
+	FlagValues []*FlagValue
+}
+
+// A generated release config.
+type ReleaseConfig struct {
+	// the Name of the release config
+	Name string
+
+	// The index of the config directory where this release config was
+	// first declared.
+	// Flag values cannot be set in a location with a lower index.
+	DeclarationIndex int
+
+	// What contributes to this config.
+	Contributions []*ReleaseConfigContribution
+
+	// Aliases for this release
+	OtherNames []string
+
+	// 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
+
+	// Generated release config
+	ReleaseConfigArtifact *rc_proto.ReleaseConfigArtifact
+
+	// We have begun compiling this release config.
+	compileInProgress bool
+
+	// Partitioned artifacts for {partition}/etc/build_flags.json
+	PartitionBuildFlags map[string]*rc_proto.FlagArtifacts
+}
+
+func ReleaseConfigFactory(name string, index int) (c *ReleaseConfig) {
+	return &ReleaseConfig{Name: name, DeclarationIndex: index}
+}
+
+func (config *ReleaseConfig) InheritConfig(iConfig *ReleaseConfig) error {
+	for _, fa := range iConfig.FlagArtifacts {
+		name := *fa.FlagDeclaration.Name
+		myFa, ok := config.FlagArtifacts[name]
+		if !ok {
+			return fmt.Errorf("Could not inherit flag %s from %s", name, iConfig.Name)
+		}
+		if name == "RELEASE_ACONFIG_VALUE_SETS" {
+			if len(fa.Traces) > 0 {
+				myFa.Traces = append(myFa.Traces, fa.Traces...)
+				myFa.Value = &rc_proto.Value{Val: &rc_proto.Value_StringValue{
+					myFa.Value.GetStringValue() + " " + fa.Value.GetStringValue()}}
+			}
+		} else if len(fa.Traces) > 1 {
+			// A value was assigned. Set our value.
+			myFa.Traces = append(myFa.Traces, fa.Traces[1:]...)
+			myFa.Value = fa.Value
+		}
+	}
+	return nil
+}
+
+func (config *ReleaseConfig) GenerateReleaseConfig(configs *ReleaseConfigs) error {
+	if config.ReleaseConfigArtifact != nil {
+		return nil
+	}
+	if config.compileInProgress {
+		return fmt.Errorf("Loop detected for release config %s", config.Name)
+	}
+	config.compileInProgress = true
+	isRoot := config.Name == "root"
+
+	// Start with only the flag declarations.
+	config.FlagArtifacts = configs.FlagArtifacts.Clone()
+	releaseAconfigValueSets := config.FlagArtifacts["RELEASE_ACONFIG_VALUE_SETS"]
+
+	// Generate any configs we need to inherit.  This will detect loops in
+	// the config.
+	contributionsToApply := []*ReleaseConfigContribution{}
+	myInherits := []string{}
+	myInheritsSet := make(map[string]bool)
+	// If there is a "root" release config, it is the start of every inheritance chain.
+	_, err := configs.GetReleaseConfig("root")
+	if err == nil && !isRoot {
+		config.InheritNames = append([]string{"root"}, config.InheritNames...)
+	}
+	for _, inherit := range config.InheritNames {
+		if _, ok := myInheritsSet[inherit]; ok {
+			continue
+		}
+		myInherits = append(myInherits, inherit)
+		myInheritsSet[inherit] = true
+		iConfig, err := configs.GetReleaseConfig(inherit)
+		if err != nil {
+			return err
+		}
+		iConfig.GenerateReleaseConfig(configs)
+		if err := config.InheritConfig(iConfig); err != nil {
+			return err
+		}
+	}
+	contributionsToApply = append(contributionsToApply, config.Contributions...)
+
+	workflowManual := rc_proto.Workflow(rc_proto.Workflow_MANUAL)
+	myDirsMap := make(map[int]bool)
+	for _, contrib := range contributionsToApply {
+		contribAconfigValueSets := []string{}
+		// Gather the aconfig_value_sets from this contribution, allowing duplicates for simplicity.
+		for _, v := range contrib.proto.AconfigValueSets {
+			contribAconfigValueSets = append(contribAconfigValueSets, v)
+		}
+		contribAconfigValueSetsString := strings.Join(contribAconfigValueSets, " ")
+		releaseAconfigValueSets.Value = &rc_proto.Value{Val: &rc_proto.Value_StringValue{
+			releaseAconfigValueSets.Value.GetStringValue() + " " + contribAconfigValueSetsString}}
+		releaseAconfigValueSets.Traces = append(
+			releaseAconfigValueSets.Traces,
+			&rc_proto.Tracepoint{
+				Source: proto.String(contrib.path),
+				Value:  &rc_proto.Value{Val: &rc_proto.Value_StringValue{contribAconfigValueSetsString}},
+			})
+
+		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]
+			if !ok {
+				return fmt.Errorf("Setting value for undefined flag %s in %s\n", name, value.path)
+			}
+			myDirsMap[fa.DeclarationIndex] = true
+			if fa.DeclarationIndex > contrib.DeclarationIndex {
+				// Setting location is to the left of declaration.
+				return fmt.Errorf("Setting value for flag %s not allowed in %s\n", name, value.path)
+			}
+			if isRoot && *fa.FlagDeclaration.Workflow != workflowManual {
+				// The "root" release config can only contain workflow: MANUAL flags.
+				return fmt.Errorf("Setting value for non-MANUAL flag %s is not allowed in %s", name, value.path)
+			}
+			if err := fa.UpdateValue(*value); err != nil {
+				return err
+			}
+			if fa.Redacted {
+				delete(config.FlagArtifacts, name)
+			}
+		}
+	}
+	// Now remove any duplicates from the actual value of RELEASE_ACONFIG_VALUE_SETS
+	myAconfigValueSets := []string{}
+	myAconfigValueSetsMap := map[string]bool{}
+	for _, v := range strings.Split(releaseAconfigValueSets.Value.GetStringValue(), " ") {
+		if myAconfigValueSetsMap[v] {
+			continue
+		}
+		myAconfigValueSetsMap[v] = true
+		myAconfigValueSets = append(myAconfigValueSets, v)
+	}
+	releaseAconfigValueSets.Value = &rc_proto.Value{Val: &rc_proto.Value_StringValue{strings.TrimSpace(strings.Join(myAconfigValueSets, " "))}}
+
+	directories := []string{}
+	for idx, confDir := range configs.configDirs {
+		if _, ok := myDirsMap[idx]; ok {
+			directories = append(directories, confDir)
+		}
+	}
+
+	// Now build the per-partition artifacts
+	config.PartitionBuildFlags = make(map[string]*rc_proto.FlagArtifacts)
+	for _, v := range config.FlagArtifacts {
+		artifact, err := v.MarshalWithoutTraces()
+		if err != nil {
+			return err
+		}
+		for _, container := range v.FlagDeclaration.Containers {
+			if _, ok := config.PartitionBuildFlags[container]; !ok {
+				config.PartitionBuildFlags[container] = &rc_proto.FlagArtifacts{}
+			}
+			config.PartitionBuildFlags[container].FlagArtifacts = append(config.PartitionBuildFlags[container].FlagArtifacts, artifact)
+		}
+	}
+	config.ReleaseConfigArtifact = &rc_proto.ReleaseConfigArtifact{
+		Name:       proto.String(config.Name),
+		OtherNames: config.OtherNames,
+		FlagArtifacts: func() []*rc_proto.FlagArtifact {
+			ret := []*rc_proto.FlagArtifact{}
+			flagNames := []string{}
+			for k := range config.FlagArtifacts {
+				flagNames = append(flagNames, k)
+			}
+			sort.Strings(flagNames)
+			for _, flagName := range flagNames {
+				flag := config.FlagArtifacts[flagName]
+				ret = append(ret, &rc_proto.FlagArtifact{
+					FlagDeclaration: flag.FlagDeclaration,
+					Traces:          flag.Traces,
+					Value:           flag.Value,
+				})
+			}
+			return ret
+		}(),
+		AconfigValueSets: myAconfigValueSets,
+		Inherits:         myInherits,
+		Directories:      directories,
+	}
+
+	config.compileInProgress = false
+	return nil
+}
+
+func (config *ReleaseConfig) WritePartitionBuildFlags(outDir, product, targetRelease string) error {
+	var err error
+	for partition, flags := range config.PartitionBuildFlags {
+		slices.SortFunc(flags.FlagArtifacts, func(a, b *rc_proto.FlagArtifact) int {
+			return cmp.Compare(*a.FlagDeclaration.Name, *b.FlagDeclaration.Name)
+		})
+		if err = WriteMessage(filepath.Join(outDir, fmt.Sprintf("build_flags_%s-%s-%s.json", partition, config.Name, product)), flags); err != nil {
+			return err
+		}
+	}
+	return nil
+}