| // Copyright 2017 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 android | 
 |  | 
 | import ( | 
 | 	"errors" | 
 | 	"fmt" | 
 | 	"path/filepath" | 
 | 	"sort" | 
 | 	"strconv" | 
 | 	"strings" | 
 | 	"sync" | 
 |  | 
 | 	"github.com/google/blueprint" | 
 | ) | 
 |  | 
 | // This file implements namespaces | 
 | const ( | 
 | 	namespacePrefix = "//" | 
 | 	modulePrefix    = ":" | 
 | ) | 
 |  | 
 | func init() { | 
 | 	RegisterModuleType("soong_namespace", NamespaceFactory) | 
 | } | 
 |  | 
 | // threadsafe sorted list | 
 | type sortedNamespaces struct { | 
 | 	lock   sync.Mutex | 
 | 	items  []*Namespace | 
 | 	sorted bool | 
 | } | 
 |  | 
 | func (s *sortedNamespaces) add(namespace *Namespace) { | 
 | 	s.lock.Lock() | 
 | 	defer s.lock.Unlock() | 
 | 	if s.sorted { | 
 | 		panic("It is not supported to call sortedNamespaces.add() after sortedNamespaces.sortedItems()") | 
 | 	} | 
 | 	s.items = append(s.items, namespace) | 
 | } | 
 |  | 
 | func (s *sortedNamespaces) sortedItems() []*Namespace { | 
 | 	s.lock.Lock() | 
 | 	defer s.lock.Unlock() | 
 | 	if !s.sorted { | 
 | 		less := func(i int, j int) bool { | 
 | 			return s.items[i].Path < s.items[j].Path | 
 | 		} | 
 | 		sort.Slice(s.items, less) | 
 | 		s.sorted = true | 
 | 	} | 
 | 	return s.items | 
 | } | 
 |  | 
 | func (s *sortedNamespaces) index(namespace *Namespace) int { | 
 | 	for i, candidate := range s.sortedItems() { | 
 | 		if namespace == candidate { | 
 | 			return i | 
 | 		} | 
 | 	} | 
 | 	return -1 | 
 | } | 
 |  | 
 | // A NameResolver implements blueprint.NameInterface, and implements the logic to | 
 | // find a module from namespaces based on a query string. | 
 | // A query string can be a module name or can be be "//namespace_path:module_path" | 
 | type NameResolver struct { | 
 | 	rootNamespace *Namespace | 
 |  | 
 | 	// id counter for atomic.AddInt32 | 
 | 	nextNamespaceId int32 | 
 |  | 
 | 	// All namespaces, without duplicates. | 
 | 	sortedNamespaces sortedNamespaces | 
 |  | 
 | 	// Map from dir to namespace. Will have duplicates if two dirs are part of the same namespace. | 
 | 	namespacesByDir sync.Map // if generics were supported, this would be sync.Map[string]*Namespace | 
 |  | 
 | 	// func telling whether to export a namespace to Kati | 
 | 	namespaceExportFilter func(*Namespace) bool | 
 | } | 
 |  | 
 | func NewNameResolver(namespaceExportFilter func(*Namespace) bool) *NameResolver { | 
 | 	namespacesByDir := sync.Map{} | 
 |  | 
 | 	r := &NameResolver{ | 
 | 		namespacesByDir:       namespacesByDir, | 
 | 		namespaceExportFilter: namespaceExportFilter, | 
 | 	} | 
 | 	r.rootNamespace = r.newNamespace(".") | 
 | 	r.rootNamespace.visibleNamespaces = []*Namespace{r.rootNamespace} | 
 | 	r.addNamespace(r.rootNamespace) | 
 |  | 
 | 	return r | 
 | } | 
 |  | 
 | func (r *NameResolver) newNamespace(path string) *Namespace { | 
 | 	namespace := NewNamespace(path) | 
 |  | 
 | 	namespace.exportToKati = r.namespaceExportFilter(namespace) | 
 |  | 
 | 	return namespace | 
 | } | 
 |  | 
 | func (r *NameResolver) addNewNamespaceForModule(module *NamespaceModule, path string) error { | 
 | 	fileName := filepath.Base(path) | 
 | 	if fileName != "Android.bp" { | 
 | 		return errors.New("A namespace may only be declared in a file named Android.bp") | 
 | 	} | 
 | 	dir := filepath.Dir(path) | 
 |  | 
 | 	namespace := r.newNamespace(dir) | 
 | 	module.namespace = namespace | 
 | 	module.resolver = r | 
 | 	namespace.importedNamespaceNames = module.properties.Imports | 
 | 	return r.addNamespace(namespace) | 
 | } | 
 |  | 
 | func (r *NameResolver) addNamespace(namespace *Namespace) (err error) { | 
 | 	existingNamespace, exists := r.namespaceAt(namespace.Path) | 
 | 	if exists { | 
 | 		if existingNamespace.Path == namespace.Path { | 
 | 			return fmt.Errorf("namespace %v already exists", namespace.Path) | 
 | 		} else { | 
 | 			// It would probably confuse readers if namespaces were declared anywhere but | 
 | 			// the top of the file, so we forbid declaring namespaces after anything else. | 
 | 			return fmt.Errorf("a namespace must be the first module in the file") | 
 | 		} | 
 | 	} | 
 | 	r.sortedNamespaces.add(namespace) | 
 |  | 
 | 	r.namespacesByDir.Store(namespace.Path, namespace) | 
 | 	return nil | 
 | } | 
 |  | 
 | // non-recursive check for namespace | 
 | func (r *NameResolver) namespaceAt(path string) (namespace *Namespace, found bool) { | 
 | 	mapVal, found := r.namespacesByDir.Load(path) | 
 | 	if !found { | 
 | 		return nil, false | 
 | 	} | 
 | 	return mapVal.(*Namespace), true | 
 | } | 
 |  | 
 | // recursive search upward for a namespace | 
 | func (r *NameResolver) findNamespace(path string) (namespace *Namespace) { | 
 | 	namespace, found := r.namespaceAt(path) | 
 | 	if found { | 
 | 		return namespace | 
 | 	} | 
 | 	parentDir := filepath.Dir(path) | 
 | 	if parentDir == path { | 
 | 		return nil | 
 | 	} | 
 | 	namespace = r.findNamespace(parentDir) | 
 | 	r.namespacesByDir.Store(path, namespace) | 
 | 	return namespace | 
 | } | 
 |  | 
 | func (r *NameResolver) NewModule(ctx blueprint.NamespaceContext, moduleGroup blueprint.ModuleGroup, module blueprint.Module) (namespace blueprint.Namespace, errs []error) { | 
 | 	// if this module is a namespace, then save it to our list of namespaces | 
 | 	newNamespace, ok := module.(*NamespaceModule) | 
 | 	if ok { | 
 | 		err := r.addNewNamespaceForModule(newNamespace, ctx.ModulePath()) | 
 | 		if err != nil { | 
 | 			return nil, []error{err} | 
 | 		} | 
 | 		return nil, nil | 
 | 	} | 
 |  | 
 | 	// if this module is not a namespace, then save it into the appropriate namespace | 
 | 	ns := r.findNamespaceFromCtx(ctx) | 
 |  | 
 | 	_, errs = ns.moduleContainer.NewModule(ctx, moduleGroup, module) | 
 | 	if len(errs) > 0 { | 
 | 		return nil, errs | 
 | 	} | 
 |  | 
 | 	amod, ok := module.(Module) | 
 | 	if ok { | 
 | 		// inform the module whether its namespace is one that we want to export to Make | 
 | 		amod.base().commonProperties.NamespaceExportedToMake = ns.exportToKati | 
 | 	} | 
 |  | 
 | 	return ns, nil | 
 | } | 
 |  | 
 | func (r *NameResolver) AllModules() []blueprint.ModuleGroup { | 
 | 	childLists := [][]blueprint.ModuleGroup{} | 
 | 	totalCount := 0 | 
 | 	for _, namespace := range r.sortedNamespaces.sortedItems() { | 
 | 		newModules := namespace.moduleContainer.AllModules() | 
 | 		totalCount += len(newModules) | 
 | 		childLists = append(childLists, newModules) | 
 | 	} | 
 |  | 
 | 	allModules := make([]blueprint.ModuleGroup, 0, totalCount) | 
 | 	for _, childList := range childLists { | 
 | 		allModules = append(allModules, childList...) | 
 | 	} | 
 | 	return allModules | 
 | } | 
 |  | 
 | // parses a fully-qualified path (like "//namespace_path:module_name") into a namespace name and a | 
 | // module name | 
 | func (r *NameResolver) parseFullyQualifiedName(name string) (namespaceName string, moduleName string, ok bool) { | 
 | 	if !strings.HasPrefix(name, namespacePrefix) { | 
 | 		return "", "", false | 
 | 	} | 
 | 	name = strings.TrimPrefix(name, namespacePrefix) | 
 | 	components := strings.Split(name, modulePrefix) | 
 | 	if len(components) != 2 { | 
 | 		return "", "", false | 
 | 	} | 
 | 	return components[0], components[1], true | 
 |  | 
 | } | 
 |  | 
 | func (r *NameResolver) getNamespacesToSearchForModule(sourceNamespace *Namespace) (searchOrder []*Namespace) { | 
 | 	return sourceNamespace.visibleNamespaces | 
 | } | 
 |  | 
 | func (r *NameResolver) ModuleFromName(name string, namespace blueprint.Namespace) (group blueprint.ModuleGroup, found bool) { | 
 | 	// handle fully qualified references like "//namespace_path:module_name" | 
 | 	nsName, moduleName, isAbs := r.parseFullyQualifiedName(name) | 
 | 	if isAbs { | 
 | 		namespace, found := r.namespaceAt(nsName) | 
 | 		if !found { | 
 | 			return blueprint.ModuleGroup{}, false | 
 | 		} | 
 | 		container := namespace.moduleContainer | 
 | 		return container.ModuleFromName(moduleName, nil) | 
 | 	} | 
 | 	for _, candidate := range r.getNamespacesToSearchForModule(namespace.(*Namespace)) { | 
 | 		group, found = candidate.moduleContainer.ModuleFromName(name, nil) | 
 | 		if found { | 
 | 			return group, true | 
 | 		} | 
 | 	} | 
 | 	return blueprint.ModuleGroup{}, false | 
 |  | 
 | } | 
 |  | 
 | func (r *NameResolver) Rename(oldName string, newName string, namespace blueprint.Namespace) []error { | 
 | 	oldNs := r.findNamespace(oldName) | 
 | 	newNs := r.findNamespace(newName) | 
 | 	if oldNs != newNs { | 
 | 		return []error{fmt.Errorf("cannot rename %v to %v because the destination is outside namespace %v", oldName, newName, oldNs.Path)} | 
 | 	} | 
 |  | 
 | 	oldName, err := filepath.Rel(oldNs.Path, oldName) | 
 | 	if err != nil { | 
 | 		panic(err) | 
 | 	} | 
 | 	newName, err = filepath.Rel(newNs.Path, newName) | 
 | 	if err != nil { | 
 | 		panic(err) | 
 | 	} | 
 |  | 
 | 	return oldNs.moduleContainer.Rename(oldName, newName, nil) | 
 | } | 
 |  | 
 | // resolve each element of namespace.importedNamespaceNames and put the result in namespace.visibleNamespaces | 
 | func (r *NameResolver) FindNamespaceImports(namespace *Namespace) (err error) { | 
 | 	namespace.visibleNamespaces = make([]*Namespace, 0, 2+len(namespace.importedNamespaceNames)) | 
 | 	// search itself first | 
 | 	namespace.visibleNamespaces = append(namespace.visibleNamespaces, namespace) | 
 | 	// search its imports next | 
 | 	for _, name := range namespace.importedNamespaceNames { | 
 | 		imp, ok := r.namespaceAt(name) | 
 | 		if !ok { | 
 | 			return fmt.Errorf("namespace %v does not exist", name) | 
 | 		} | 
 | 		namespace.visibleNamespaces = append(namespace.visibleNamespaces, imp) | 
 | 	} | 
 | 	// search the root namespace last | 
 | 	namespace.visibleNamespaces = append(namespace.visibleNamespaces, r.rootNamespace) | 
 | 	return nil | 
 | } | 
 |  | 
 | func (r *NameResolver) chooseId(namespace *Namespace) { | 
 | 	id := r.sortedNamespaces.index(namespace) | 
 | 	if id < 0 { | 
 | 		panic(fmt.Sprintf("Namespace not found: %v\n", namespace.id)) | 
 | 	} | 
 | 	namespace.id = strconv.Itoa(id) | 
 | } | 
 |  | 
 | func (r *NameResolver) MissingDependencyError(depender string, dependerNamespace blueprint.Namespace, depName string) (err error) { | 
 | 	text := fmt.Sprintf("%q depends on undefined module %q", depender, depName) | 
 |  | 
 | 	_, _, isAbs := r.parseFullyQualifiedName(depName) | 
 | 	if isAbs { | 
 | 		// if the user gave a fully-qualified name, we don't need to look for other | 
 | 		// modules that they might have been referring to | 
 | 		return fmt.Errorf(text) | 
 | 	} | 
 |  | 
 | 	// determine which namespaces the module can be found in | 
 | 	foundInNamespaces := []string{} | 
 | 	for _, namespace := range r.sortedNamespaces.sortedItems() { | 
 | 		_, found := namespace.moduleContainer.ModuleFromName(depName, nil) | 
 | 		if found { | 
 | 			foundInNamespaces = append(foundInNamespaces, namespace.Path) | 
 | 		} | 
 | 	} | 
 | 	if len(foundInNamespaces) > 0 { | 
 | 		// determine which namespaces are visible to dependerNamespace | 
 | 		dependerNs := dependerNamespace.(*Namespace) | 
 | 		searched := r.getNamespacesToSearchForModule(dependerNs) | 
 | 		importedNames := []string{} | 
 | 		for _, ns := range searched { | 
 | 			importedNames = append(importedNames, ns.Path) | 
 | 		} | 
 | 		text += fmt.Sprintf("\nModule %q is defined in namespace %q which can read these %v namespaces: %q", depender, dependerNs.Path, len(importedNames), importedNames) | 
 | 		text += fmt.Sprintf("\nModule %q can be found in these namespaces: %q", depName, foundInNamespaces) | 
 | 	} | 
 |  | 
 | 	return fmt.Errorf(text) | 
 | } | 
 |  | 
 | func (r *NameResolver) GetNamespace(ctx blueprint.NamespaceContext) blueprint.Namespace { | 
 | 	return r.findNamespaceFromCtx(ctx) | 
 | } | 
 |  | 
 | func (r *NameResolver) findNamespaceFromCtx(ctx blueprint.NamespaceContext) *Namespace { | 
 | 	return r.findNamespace(filepath.Dir(ctx.ModulePath())) | 
 | } | 
 |  | 
 | func (r *NameResolver) UniqueName(ctx blueprint.NamespaceContext, name string) (unique string) { | 
 | 	prefix := r.findNamespaceFromCtx(ctx).id | 
 | 	if prefix != "" { | 
 | 		prefix = prefix + "-" | 
 | 	} | 
 | 	return prefix + name | 
 | } | 
 |  | 
 | var _ blueprint.NameInterface = (*NameResolver)(nil) | 
 |  | 
 | type Namespace struct { | 
 | 	blueprint.NamespaceMarker | 
 | 	Path string | 
 |  | 
 | 	// names of namespaces listed as imports by this namespace | 
 | 	importedNamespaceNames []string | 
 | 	// all namespaces that should be searched when a module in this namespace declares a dependency | 
 | 	visibleNamespaces []*Namespace | 
 |  | 
 | 	id string | 
 |  | 
 | 	exportToKati bool | 
 |  | 
 | 	moduleContainer blueprint.NameInterface | 
 | } | 
 |  | 
 | func NewNamespace(path string) *Namespace { | 
 | 	return &Namespace{Path: path, moduleContainer: blueprint.NewSimpleNameInterface()} | 
 | } | 
 |  | 
 | var _ blueprint.Namespace = (*Namespace)(nil) | 
 |  | 
 | type NamespaceModule struct { | 
 | 	ModuleBase | 
 |  | 
 | 	namespace *Namespace | 
 | 	resolver  *NameResolver | 
 |  | 
 | 	properties struct { | 
 | 		Imports []string | 
 | 	} | 
 | } | 
 |  | 
 | func (n *NamespaceModule) DepsMutator(context BottomUpMutatorContext) { | 
 | } | 
 |  | 
 | func (n *NamespaceModule) GenerateAndroidBuildActions(ctx ModuleContext) { | 
 | } | 
 |  | 
 | func (n *NamespaceModule) GenerateBuildActions(ctx blueprint.ModuleContext) { | 
 | } | 
 |  | 
 | func (n *NamespaceModule) Name() (name string) { | 
 | 	return *n.nameProperties.Name | 
 | } | 
 |  | 
 | func NamespaceFactory() Module { | 
 | 	module := &NamespaceModule{} | 
 |  | 
 | 	name := "soong_namespace" | 
 | 	module.nameProperties.Name = &name | 
 |  | 
 | 	module.AddProperties(&module.properties) | 
 | 	return module | 
 | } | 
 |  | 
 | func RegisterNamespaceMutator(ctx RegisterMutatorsContext) { | 
 | 	ctx.BottomUp("namespace_deps", namespaceMutator).Parallel() | 
 | } | 
 |  | 
 | func namespaceMutator(ctx BottomUpMutatorContext) { | 
 | 	module, ok := ctx.Module().(*NamespaceModule) | 
 | 	if ok { | 
 | 		err := module.resolver.FindNamespaceImports(module.namespace) | 
 | 		if err != nil { | 
 | 			ctx.ModuleErrorf(err.Error()) | 
 | 		} | 
 |  | 
 | 		module.resolver.chooseId(module.namespace) | 
 | 	} | 
 | } |