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1// Copyright 2016 Google Inc. All rights reserved.
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//     http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15package android
16
17import (
18	"fmt"
19	"reflect"
20	"strings"
21
22	"github.com/google/blueprint"
23	"github.com/google/blueprint/proptools"
24)
25
26// This file implements common functionality for handling modules that may exist as prebuilts,
27// source, or both.
28
29func RegisterPrebuiltMutators(ctx RegistrationContext) {
30	ctx.PreArchMutators(RegisterPrebuiltsPreArchMutators)
31	ctx.PreDepsMutators(RegisterPrebuiltsPreDepsMutators)
32	ctx.PostDepsMutators(RegisterPrebuiltsPostDepsMutators)
33}
34
35// Marks a dependency tag as possibly preventing a reference to a source from being
36// replaced with the prebuilt.
37type ReplaceSourceWithPrebuilt interface {
38	blueprint.DependencyTag
39
40	// Return true if the dependency defined by this tag should be replaced with the
41	// prebuilt.
42	ReplaceSourceWithPrebuilt() bool
43}
44
45type prebuiltDependencyTag struct {
46	blueprint.BaseDependencyTag
47}
48
49var PrebuiltDepTag prebuiltDependencyTag
50
51// Mark this tag so dependencies that use it are excluded from visibility enforcement.
52func (t prebuiltDependencyTag) ExcludeFromVisibilityEnforcement() {}
53
54// Mark this tag so dependencies that use it are excluded from APEX contents.
55func (t prebuiltDependencyTag) ExcludeFromApexContents() {}
56
57var _ ExcludeFromVisibilityEnforcementTag = PrebuiltDepTag
58var _ ExcludeFromApexContentsTag = PrebuiltDepTag
59
60// UserSuppliedPrebuiltProperties contains the prebuilt properties that can be specified in an
61// Android.bp file.
62type UserSuppliedPrebuiltProperties struct {
63	// When prefer is set to true the prebuilt will be used instead of any source module with
64	// a matching name.
65	Prefer proptools.Configurable[bool] `android:"arch_variant,replace_instead_of_append"`
66
67	// When specified this names a Soong config variable that controls the prefer property.
68	//
69	// If the value of the named Soong config variable is true then prefer is set to false and vice
70	// versa. If the Soong config variable is not set then it defaults to false, so prefer defaults
71	// to true.
72	//
73	// If specified then the prefer property is ignored in favor of the value of the Soong config
74	// variable.
75	//
76	// DEPRECATED: This property is being deprecated b/308188211.
77	// Use RELEASE_APEX_CONTRIBUTIONS build flags to select prebuilts of mainline modules.
78	Use_source_config_var *ConfigVarProperties
79}
80
81// CopyUserSuppliedPropertiesFromPrebuilt copies the user supplied prebuilt properties from the
82// prebuilt properties.
83func (u *UserSuppliedPrebuiltProperties) CopyUserSuppliedPropertiesFromPrebuilt(p *Prebuilt) {
84	*u = p.properties.UserSuppliedPrebuiltProperties
85}
86
87type PrebuiltProperties struct {
88	UserSuppliedPrebuiltProperties
89
90	SourceExists bool `blueprint:"mutated"`
91	UsePrebuilt  bool `blueprint:"mutated"`
92
93	// Set if the module has been renamed to remove the "prebuilt_" prefix.
94	PrebuiltRenamedToSource bool `blueprint:"mutated"`
95}
96
97// Properties that can be used to select a Soong config variable.
98type ConfigVarProperties struct {
99	// Allow instances of this struct to be used as a property value in a BpPropertySet.
100	BpPrintableBase
101
102	// The name of the configuration namespace.
103	//
104	// As passed to add_soong_config_namespace in Make.
105	Config_namespace *string
106
107	// The name of the configuration variable.
108	//
109	// As passed to add_soong_config_var_value in Make.
110	Var_name *string
111}
112
113type Prebuilt struct {
114	properties PrebuiltProperties
115
116	// nil if the prebuilt has no srcs property at all. See InitPrebuiltModuleWithoutSrcs.
117	srcsSupplier PrebuiltSrcsSupplier
118
119	// "-" if the prebuilt has no srcs property at all. See InitPrebuiltModuleWithoutSrcs.
120	srcsPropertyName string
121}
122
123// RemoveOptionalPrebuiltPrefix returns the result of removing the "prebuilt_" prefix from the
124// supplied name if it has one, or returns the name unmodified if it does not.
125func RemoveOptionalPrebuiltPrefix(name string) string {
126	return strings.TrimPrefix(name, "prebuilt_")
127}
128
129// RemoveOptionalPrebuiltPrefixFromBazelLabel removes the "prebuilt_" prefix from the *target name* of a Bazel label.
130// This differs from RemoveOptionalPrebuiltPrefix in that it does not remove it from the start of the string, but
131// instead removes it from the target name itself.
132func RemoveOptionalPrebuiltPrefixFromBazelLabel(label string) string {
133	splitLabel := strings.Split(label, ":")
134	bazelModuleNameNoPrebuilt := RemoveOptionalPrebuiltPrefix(splitLabel[1])
135	return strings.Join([]string{
136		splitLabel[0],
137		bazelModuleNameNoPrebuilt,
138	}, ":")
139}
140
141func (p *Prebuilt) Name(name string) string {
142	return PrebuiltNameFromSource(name)
143}
144
145// PrebuiltNameFromSource returns the result of prepending the "prebuilt_" prefix to the supplied
146// name.
147func PrebuiltNameFromSource(name string) string {
148	return "prebuilt_" + name
149}
150
151func (p *Prebuilt) ForcePrefer() {
152	p.properties.Prefer = NewSimpleConfigurable(true)
153}
154
155// SingleSourcePathFromSupplier invokes the supplied supplier for the current module in the
156// supplied context to retrieve a list of file paths, ensures that the returned list of file paths
157// contains a single value and then assumes that is a module relative file path and converts it to
158// a Path accordingly.
159//
160// Any issues, such as nil supplier or not exactly one file path will be reported as errors on the
161// supplied context and this will return nil.
162func SingleSourcePathFromSupplier(ctx ModuleContext, srcsSupplier PrebuiltSrcsSupplier, srcsPropertyName string) Path {
163	if srcsSupplier != nil {
164		srcs := srcsSupplier(ctx, ctx.Module())
165
166		if len(srcs) == 0 {
167			ctx.PropertyErrorf(srcsPropertyName, "missing prebuilt source file")
168			return nil
169		}
170
171		if len(srcs) > 1 {
172			ctx.PropertyErrorf(srcsPropertyName, "multiple prebuilt source files")
173			return nil
174		}
175
176		// Return the singleton source after expanding any filegroup in the
177		// sources.
178		src := srcs[0]
179		return PathForModuleSrc(ctx, src)
180	} else {
181		ctx.ModuleErrorf("prebuilt source was not set")
182		return nil
183	}
184}
185
186// The below source-related functions and the srcs, src fields are based on an assumption that
187// prebuilt modules have a static source property at the moment. Currently there is only one
188// exception, android_app_import, which chooses a source file depending on the product's DPI
189// preference configs. We'll want to add native support for dynamic source cases if we end up having
190// more modules like this.
191func (p *Prebuilt) SingleSourcePath(ctx ModuleContext) Path {
192	return SingleSourcePathFromSupplier(ctx, p.srcsSupplier, p.srcsPropertyName)
193}
194
195func (p *Prebuilt) UsePrebuilt() bool {
196	return p.properties.UsePrebuilt
197}
198
199func (p *Prebuilt) SetUsePrebuilt(use bool) {
200	p.properties.UsePrebuilt = use
201}
202
203// Called to provide the srcs value for the prebuilt module.
204//
205// This can be called with a context for any module not just the prebuilt one itself. It can also be
206// called concurrently.
207//
208// Return the src value or nil if it is not available.
209type PrebuiltSrcsSupplier func(ctx BaseModuleContext, prebuilt Module) []string
210
211func initPrebuiltModuleCommon(module PrebuiltInterface) *Prebuilt {
212	p := module.Prebuilt()
213	module.AddProperties(&p.properties)
214	return p
215}
216
217// Initialize the module as a prebuilt module that has no dedicated property that lists its
218// sources. SingleSourcePathFromSupplier should not be called for this module.
219//
220// This is the case e.g. for header modules, which provides the headers in source form
221// regardless whether they are prebuilt or not.
222func InitPrebuiltModuleWithoutSrcs(module PrebuiltInterface) {
223	p := initPrebuiltModuleCommon(module)
224	p.srcsPropertyName = "-"
225}
226
227// Initialize the module as a prebuilt module that uses the provided supplier to access the
228// prebuilt sources of the module.
229//
230// The supplier will be called multiple times and must return the same values each time it
231// is called. If it returns an empty array (or nil) then the prebuilt module will not be used
232// as a replacement for a source module with the same name even if prefer = true.
233//
234// If the Prebuilt.SingleSourcePath() is called on the module then this must return an array
235// containing exactly one source file.
236//
237// The provided property name is used to provide helpful error messages in the event that
238// a problem arises, e.g. calling SingleSourcePath() when more than one source is provided.
239func InitPrebuiltModuleWithSrcSupplier(module PrebuiltInterface, srcsSupplier PrebuiltSrcsSupplier, srcsPropertyName string) {
240	if srcsSupplier == nil {
241		panic(fmt.Errorf("srcsSupplier must not be nil"))
242	}
243	if srcsPropertyName == "" {
244		panic(fmt.Errorf("srcsPropertyName must not be empty"))
245	}
246
247	p := initPrebuiltModuleCommon(module)
248	p.srcsSupplier = srcsSupplier
249	p.srcsPropertyName = srcsPropertyName
250}
251
252// InitPrebuiltModule is the same as InitPrebuiltModuleWithSrcSupplier, but uses the
253// provided list of strings property as the source provider.
254func InitPrebuiltModule(module PrebuiltInterface, srcs *[]string) {
255	if srcs == nil {
256		panic(fmt.Errorf("srcs must not be nil"))
257	}
258
259	srcsSupplier := func(ctx BaseModuleContext, _ Module) []string {
260		return *srcs
261	}
262
263	InitPrebuiltModuleWithSrcSupplier(module, srcsSupplier, "srcs")
264}
265
266// InitConfigurablePrebuiltModule is the same as InitPrebuiltModule, but uses a
267// Configurable list of strings property instead of a regular list of strings.
268func InitConfigurablePrebuiltModule(module PrebuiltInterface, srcs *proptools.Configurable[[]string]) {
269	if srcs == nil {
270		panic(fmt.Errorf("srcs must not be nil"))
271	}
272
273	srcsSupplier := func(ctx BaseModuleContext, _ Module) []string {
274		return srcs.GetOrDefault(ctx, nil)
275	}
276
277	InitPrebuiltModuleWithSrcSupplier(module, srcsSupplier, "srcs")
278}
279
280// InitConfigurablePrebuiltModuleString is the same as InitPrebuiltModule, but uses a
281// Configurable string property instead of a regular list of strings. It only produces a single
282// source file.
283func InitConfigurablePrebuiltModuleString(module PrebuiltInterface, srcs *proptools.Configurable[string], propertyName string) {
284	if srcs == nil {
285		panic(fmt.Errorf("%s must not be nil", propertyName))
286	}
287
288	srcsSupplier := func(ctx BaseModuleContext, _ Module) []string {
289		src := srcs.GetOrDefault(ctx, "")
290		if src == "" {
291			return nil
292		}
293		return []string{src}
294	}
295
296	InitPrebuiltModuleWithSrcSupplier(module, srcsSupplier, propertyName)
297}
298
299func InitSingleSourcePrebuiltModule(module PrebuiltInterface, srcProps interface{}, srcField string) {
300	srcPropsValue := reflect.ValueOf(srcProps).Elem()
301	srcStructField, _ := srcPropsValue.Type().FieldByName(srcField)
302	if !srcPropsValue.IsValid() || srcStructField.Name == "" {
303		panic(fmt.Errorf("invalid single source prebuilt %+v", module))
304	}
305
306	if srcPropsValue.Kind() != reflect.Struct && srcPropsValue.Kind() != reflect.Interface {
307		panic(fmt.Errorf("invalid single source prebuilt %+v", srcProps))
308	}
309
310	srcFieldIndex := srcStructField.Index
311	srcPropertyName := proptools.PropertyNameForField(srcField)
312
313	srcsSupplier := func(ctx BaseModuleContext, _ Module) []string {
314		if !module.Enabled(ctx) {
315			return nil
316		}
317		value := srcPropsValue.FieldByIndex(srcFieldIndex)
318		if value.Kind() == reflect.Ptr {
319			if value.IsNil() {
320				return nil
321			}
322			value = value.Elem()
323		}
324		if value.Kind() != reflect.String {
325			panic(fmt.Errorf("prebuilt src field %q in %T in module %s should be a string or a pointer to one but was %v", srcField, srcProps, module, value))
326		}
327		src := value.String()
328		if src == "" {
329			return nil
330		}
331		return []string{src}
332	}
333
334	InitPrebuiltModuleWithSrcSupplier(module, srcsSupplier, srcPropertyName)
335}
336
337type PrebuiltInterface interface {
338	Module
339	Prebuilt() *Prebuilt
340}
341
342// IsModulePreferred returns true if the given module is preferred.
343//
344// A source module is preferred if there is no corresponding prebuilt module or the prebuilt module
345// does not have "prefer: true".
346//
347// A prebuilt module is preferred if there is no corresponding source module or the prebuilt module
348// has "prefer: true".
349func IsModulePreferred(module Module) bool {
350	if module.IsReplacedByPrebuilt() {
351		// A source module that has been replaced by a prebuilt counterpart.
352		return false
353	}
354	if p := GetEmbeddedPrebuilt(module); p != nil {
355		return p.UsePrebuilt()
356	}
357	return true
358}
359
360func IsModulePreferredProxy(ctx OtherModuleProviderContext, module ModuleProxy) bool {
361	if OtherModulePointerProviderOrDefault(ctx, module, CommonModuleInfoProvider).ReplacedByPrebuilt {
362		// A source module that has been replaced by a prebuilt counterpart.
363		return false
364	}
365	if p, ok := OtherModuleProvider(ctx, module, PrebuiltModuleInfoProvider); ok {
366		return p.UsePrebuilt
367	}
368	return true
369}
370
371// IsModulePrebuilt returns true if the module implements PrebuiltInterface and
372// has been initialized as a prebuilt and so returns a non-nil value from the
373// PrebuiltInterface.Prebuilt() method.
374func IsModulePrebuilt(module Module) bool {
375	return GetEmbeddedPrebuilt(module) != nil
376}
377
378// GetEmbeddedPrebuilt returns a pointer to the embedded Prebuilt structure or
379// nil if the module does not implement PrebuiltInterface or has not been
380// initialized as a prebuilt module.
381func GetEmbeddedPrebuilt(module Module) *Prebuilt {
382	if p, ok := module.(PrebuiltInterface); ok {
383		return p.Prebuilt()
384	}
385
386	return nil
387}
388
389// PrebuiltGetPreferred returns the module that is preferred for the given
390// module. That is either the module itself or the prebuilt counterpart that has
391// taken its place. The given module must be a direct dependency of the current
392// context module, and it must be the source module if both source and prebuilt
393// exist.
394//
395// This function is for use on dependencies after PrebuiltPostDepsMutator has
396// run - any dependency that is registered before that will already reference
397// the right module. This function is only safe to call after all TransitionMutators
398// have run, e.g. in GenerateAndroidBuildActions.
399func PrebuiltGetPreferred(ctx BaseModuleContext, module Module) Module {
400	if !OtherModulePointerProviderOrDefault(ctx, module, CommonModuleInfoProvider).ReplacedByPrebuilt {
401		return module
402	}
403	if _, ok := OtherModuleProvider(ctx, module, PrebuiltModuleInfoProvider); ok {
404		// If we're given a prebuilt then assume there's no source module around.
405		return module
406	}
407
408	sourceModDepFound := false
409	var prebuiltMod Module
410
411	ctx.WalkDepsProxy(func(child, parent ModuleProxy) bool {
412		if prebuiltMod != nil {
413			return false
414		}
415		if EqualModules(parent, ctx.Module()) {
416			// First level: Only recurse if the module is found as a direct dependency.
417			sourceModDepFound = child == module
418			return sourceModDepFound
419		}
420		// Second level: Follow PrebuiltDepTag to the prebuilt.
421		if t := ctx.OtherModuleDependencyTag(child); t == PrebuiltDepTag {
422			prebuiltMod = child
423		}
424		return false
425	})
426
427	if prebuiltMod == nil {
428		if !sourceModDepFound {
429			panic(fmt.Errorf("Failed to find source module as a direct dependency: %s", module))
430		} else {
431			panic(fmt.Errorf("Failed to find prebuilt for source module: %s", module))
432		}
433	}
434	return prebuiltMod
435}
436
437func RegisterPrebuiltsPreArchMutators(ctx RegisterMutatorsContext) {
438	ctx.BottomUp("prebuilt_rename", PrebuiltRenameMutator).UsesRename()
439}
440
441func RegisterPrebuiltsPreDepsMutators(ctx RegisterMutatorsContext) {
442	ctx.BottomUp("prebuilt_source", PrebuiltSourceDepsMutator).UsesReverseDependencies()
443	ctx.BottomUp("prebuilt_select", PrebuiltSelectModuleMutator)
444}
445
446func RegisterPrebuiltsPostDepsMutators(ctx RegisterMutatorsContext) {
447	ctx.BottomUp("prebuilt_postdeps", PrebuiltPostDepsMutator).UsesReplaceDependencies()
448}
449
450// Returns the name of the source module corresponding to a prebuilt module
451// For source modules, it returns its own name
452type baseModuleName interface {
453	BaseModuleName() string
454}
455
456// PrebuiltRenameMutator ensures that there always is a module with an
457// undecorated name.
458func PrebuiltRenameMutator(ctx BottomUpMutatorContext) {
459	m := ctx.Module()
460	if p := GetEmbeddedPrebuilt(m); p != nil {
461		bmn, _ := m.(baseModuleName)
462		name := bmn.BaseModuleName()
463		if !ctx.OtherModuleExists(name) {
464			ctx.Rename(name)
465			p.properties.PrebuiltRenamedToSource = true
466		}
467	}
468}
469
470// PrebuiltSourceDepsMutator adds dependencies to the prebuilt module from the
471// corresponding source module, if one exists for the same variant.
472// Add a dependency from the prebuilt to `all_apex_contributions`
473// The metadata will be used for source vs prebuilts selection
474func PrebuiltSourceDepsMutator(ctx BottomUpMutatorContext) {
475	m := ctx.Module()
476	if p := GetEmbeddedPrebuilt(m); p != nil {
477		// Add a dependency from the prebuilt to the `all_apex_contributions`
478		// metadata module
479		// TODO: When all branches contain this singleton module, make this strict
480		// TODO: Add this dependency only for mainline prebuilts and not every prebuilt module
481		if ctx.OtherModuleExists("all_apex_contributions") {
482			ctx.AddDependency(m, AcDepTag, "all_apex_contributions")
483		}
484		if m.Enabled(ctx) && !p.properties.PrebuiltRenamedToSource {
485			// If this module is a prebuilt, is enabled and has not been renamed to source then add a
486			// dependency onto the source if it is present.
487			bmn, _ := m.(baseModuleName)
488			name := bmn.BaseModuleName()
489			if ctx.OtherModuleReverseDependencyVariantExists(name) {
490				ctx.AddReverseVariationDependency(nil, PrebuiltDepTag, name)
491				p.properties.SourceExists = true
492			}
493		}
494	}
495}
496
497// checkInvariantsForSourceAndPrebuilt checks if invariants are kept when replacing
498// source with prebuilt. Note that the current module for the context is the source module.
499func checkInvariantsForSourceAndPrebuilt(ctx BaseModuleContext, s, p Module) {
500	if _, ok := s.(OverrideModule); ok {
501		// skip the check when the source module is `override_X` because it's only a placeholder
502		// for the actual source module. The check will be invoked for the actual module.
503		return
504	}
505	if sourcePartition, prebuiltPartition := s.PartitionTag(ctx.DeviceConfig()), p.PartitionTag(ctx.DeviceConfig()); sourcePartition != prebuiltPartition {
506		ctx.OtherModuleErrorf(p, "partition is different: %s(%s) != %s(%s)",
507			sourcePartition, ctx.ModuleName(), prebuiltPartition, ctx.OtherModuleName(p))
508	}
509}
510
511// PrebuiltSelectModuleMutator marks prebuilts that are used, either overriding source modules or
512// because the source module doesn't exist.  It also disables installing overridden source modules.
513//
514// If the visited module is the metadata module `all_apex_contributions`, it sets a
515// provider containing metadata about whether source or prebuilt of mainline modules should be used.
516// This logic was added here to prevent the overhead of creating a new mutator.
517func PrebuiltSelectModuleMutator(ctx BottomUpMutatorContext) {
518	m := ctx.Module()
519	if p := GetEmbeddedPrebuilt(m); p != nil {
520		if p.srcsSupplier == nil && p.srcsPropertyName == "" {
521			panic(fmt.Errorf("prebuilt module did not have InitPrebuiltModule called on it"))
522		}
523		if !p.properties.SourceExists {
524			p.properties.UsePrebuilt = p.usePrebuilt(ctx, nil, m)
525		}
526		// Propagate the provider received from `all_apex_contributions`
527		// to the source module
528		ctx.VisitDirectDepsWithTag(AcDepTag, func(am Module) {
529			psi, _ := OtherModuleProvider(ctx, am, PrebuiltSelectionInfoProvider)
530			SetProvider(ctx, PrebuiltSelectionInfoProvider, psi)
531		})
532
533	} else if s, ok := ctx.Module().(Module); ok {
534		// Use `all_apex_contributions` for source vs prebuilt selection.
535		psi := PrebuiltSelectionInfoMap{}
536		ctx.VisitDirectDepsWithTag(PrebuiltDepTag, func(am Module) {
537			// The value of psi gets overwritten with the provider from the last visited prebuilt.
538			// But all prebuilts have the same value of the provider, so this should be idempontent.
539			psi, _ = OtherModuleProvider(ctx, am, PrebuiltSelectionInfoProvider)
540		})
541		ctx.VisitDirectDepsWithTag(PrebuiltDepTag, func(prebuiltModule Module) {
542			p := GetEmbeddedPrebuilt(prebuiltModule)
543			if p.usePrebuilt(ctx, s, prebuiltModule) {
544				checkInvariantsForSourceAndPrebuilt(ctx, s, prebuiltModule)
545
546				p.properties.UsePrebuilt = true
547				s.ReplacedByPrebuilt()
548			}
549		})
550
551		// If any module in this mainline module family has been flagged using apex_contributions, disable every other module in that family
552		// Add source
553		allModules := []Module{s}
554		// Add each prebuilt
555		ctx.VisitDirectDepsWithTag(PrebuiltDepTag, func(prebuiltModule Module) {
556			allModules = append(allModules, prebuiltModule)
557		})
558		hideUnflaggedModules(ctx, psi, allModules)
559
560	}
561
562	// If this is `all_apex_contributions`, set a provider containing
563	// metadata about source vs prebuilts selection
564	if am, ok := m.(*allApexContributions); ok {
565		am.SetPrebuiltSelectionInfoProvider(ctx)
566	}
567}
568
569// If any module in this mainline module family has been flagged using apex_contributions, disable every other module in that family
570func hideUnflaggedModules(ctx BottomUpMutatorContext, psi PrebuiltSelectionInfoMap, allModulesInFamily []Module) {
571	var selectedModuleInFamily Module
572	// query all_apex_contributions to see if any module in this family has been selected
573	for _, moduleInFamily := range allModulesInFamily {
574		// validate that are no duplicates
575		if isSelected(psi, moduleInFamily) {
576			if selectedModuleInFamily == nil {
577				// Store this so we can validate that there are no duplicates
578				selectedModuleInFamily = moduleInFamily
579			} else {
580				// There are duplicate modules from the same mainline module family
581				ctx.ModuleErrorf("Found duplicate variations of the same module in apex_contributions: %s and %s. Please remove one of these.\n", selectedModuleInFamily.Name(), moduleInFamily.Name())
582			}
583		}
584	}
585
586	// If a module has been selected, hide all other modules
587	if selectedModuleInFamily != nil {
588		for _, moduleInFamily := range allModulesInFamily {
589			if moduleInFamily.Name() != selectedModuleInFamily.Name() {
590				moduleInFamily.HideFromMake()
591				moduleInFamily.SkipInstall()
592				// If this is a prebuilt module, unset properties.UsePrebuilt
593				// properties.UsePrebuilt might evaluate to true via soong config var fallback mechanism
594				// Set it to false explicitly so that the following mutator does not replace rdeps to this unselected prebuilt
595				if p := GetEmbeddedPrebuilt(moduleInFamily); p != nil {
596					p.properties.UsePrebuilt = false
597				}
598			}
599		}
600	}
601	// Do a validation pass to make sure that multiple prebuilts of a specific module are not selected.
602	// This might happen if the prebuilts share the same soong config var namespace.
603	// This should be an error, unless one of the prebuilts has been explicitly declared in apex_contributions
604	var selectedPrebuilt Module
605	for _, moduleInFamily := range allModulesInFamily {
606		// Skip if this module is in a different namespace
607		if !moduleInFamily.ExportedToMake() {
608			continue
609		}
610		if p := GetEmbeddedPrebuilt(moduleInFamily); p != nil && p.properties.UsePrebuilt {
611			if selectedPrebuilt == nil {
612				selectedPrebuilt = moduleInFamily
613			} else {
614				ctx.ModuleErrorf("Multiple prebuilt modules %v and %v have been marked as preferred for this source module. "+
615					"Please add the appropriate prebuilt module to apex_contributions for this release config.", selectedPrebuilt.Name(), moduleInFamily.Name())
616			}
617		}
618	}
619}
620
621func IsDontReplaceSourceWithPrebuiltTag(tag blueprint.DependencyTag) bool {
622	if t, ok := tag.(ReplaceSourceWithPrebuilt); ok {
623		return !t.ReplaceSourceWithPrebuilt()
624	}
625	return false
626}
627
628// PrebuiltPostDepsMutator replaces dependencies on the source module with dependencies on the
629// prebuilt when both modules exist and the prebuilt should be used.  When the prebuilt should not
630// be used, disable installing it.
631func PrebuiltPostDepsMutator(ctx BottomUpMutatorContext) {
632	m := ctx.Module()
633	if p := GetEmbeddedPrebuilt(m); p != nil {
634		bmn, _ := m.(baseModuleName)
635		name := bmn.BaseModuleName()
636
637		if p.properties.UsePrebuilt {
638			if p.properties.SourceExists {
639				ctx.ReplaceDependenciesIf(name, func(from blueprint.Module, tag blueprint.DependencyTag, to blueprint.Module) bool {
640					if t, ok := tag.(ReplaceSourceWithPrebuilt); ok {
641						return t.ReplaceSourceWithPrebuilt()
642					}
643					return true
644				})
645			}
646		} else {
647			m.HideFromMake()
648			m.SkipInstall()
649		}
650	}
651}
652
653// A wrapper around PrebuiltSelectionInfoMap.IsSelected with special handling for java_sdk_library
654// java_sdk_library is a macro that creates
655// 1. top-level impl library
656// 2. stub libraries (suffixed with .stubs...)
657//
658// java_sdk_library_import is a macro that creates
659// 1. top-level "impl" library
660// 2. stub libraries (suffixed with .stubs...)
661func isSelected(psi PrebuiltSelectionInfoMap, m Module) bool {
662	if sdkLibrary, ok := m.(interface{ SdkLibraryName() *string }); ok && sdkLibrary.SdkLibraryName() != nil {
663		sln := proptools.String(sdkLibrary.SdkLibraryName())
664
665		// This is the top-level library
666		if bmn, ok := m.(baseModuleName); ok && sln == bmn.BaseModuleName() {
667			return psi.IsSelected(m.Name())
668		}
669
670		// Stub library created by java_sdk_library_import
671		// java_sdk_library creates several child modules (java_import + prebuilt_stubs_sources) dynamically.
672		// This code block ensures that these child modules are selected if the top-level java_sdk_library_import is listed
673		// in the selected apex_contributions.
674		if javaImport, ok := m.(createdByJavaSdkLibraryName); ok && javaImport.CreatedByJavaSdkLibraryName() != nil {
675			return psi.IsSelected(PrebuiltNameFromSource(proptools.String(javaImport.CreatedByJavaSdkLibraryName())))
676		}
677
678		// Stub library created by java_sdk_library
679		return psi.IsSelected(sln)
680	}
681	return psi.IsSelected(m.Name())
682}
683
684// implemented by child modules of java_sdk_library_import
685type createdByJavaSdkLibraryName interface {
686	CreatedByJavaSdkLibraryName() *string
687}
688
689// Returns true if the prebuilt variant is disabled
690// e.g. for a cc_prebuilt_library_shared, this will return
691// - true for the static variant of the module
692// - false for the shared variant of the module
693//
694// Even though this is a cc_prebuilt_library_shared, we create both the variants today
695// https://source.corp.google.com/h/googleplex-android/platform/build/soong/+/e08e32b45a18a77bc3c3e751f730539b1b374f1b:cc/library.go;l=2113-2116;drc=2c4a9779cd1921d0397a12b3d3521f4c9b30d747;bpv=1;bpt=0
696func (p *Prebuilt) variantIsDisabled(ctx BaseModuleContext, prebuilt Module) bool {
697	return p.srcsSupplier != nil && len(p.srcsSupplier(ctx, prebuilt)) == 0
698}
699
700type apexVariationName interface {
701	ApexVariationName() string
702}
703
704// usePrebuilt returns true if a prebuilt should be used instead of the source module.  The prebuilt
705// will be used if it is marked "prefer" or if the source module is disabled.
706func (p *Prebuilt) usePrebuilt(ctx BaseModuleContext, source Module, prebuilt Module) bool {
707	isMainlinePrebuilt := func(prebuilt Module) bool {
708		apex, ok := prebuilt.(apexVariationName)
709		if !ok {
710			return false
711		}
712		// Prebuilts of aosp apexes in prebuilts/runtime
713		// Used in minimal art branches
714		if prebuilt.base().BaseModuleName() == apex.ApexVariationName() {
715			return false
716		}
717		return InList(apex.ApexVariationName(), ctx.Config().AllMainlineApexNames())
718	}
719
720	// Use `all_apex_contributions` for source vs prebuilt selection.
721	psi := PrebuiltSelectionInfoMap{}
722	var psiDepTag blueprint.DependencyTag
723	if p := GetEmbeddedPrebuilt(ctx.Module()); p != nil {
724		// This is a prebuilt module, visit all_apex_contributions to get the info
725		psiDepTag = AcDepTag
726	} else {
727		// This is a source module, visit any of its prebuilts to get the info
728		psiDepTag = PrebuiltDepTag
729	}
730	ctx.VisitDirectDepsWithTag(psiDepTag, func(am Module) {
731		psi, _ = OtherModuleProvider(ctx, am, PrebuiltSelectionInfoProvider)
732	})
733
734	// If the source module is explicitly listed in the metadata module, use that
735	if source != nil && isSelected(psi, source) {
736		return false
737	}
738	// If the prebuilt module is explicitly listed in the metadata module, use that
739	if isSelected(psi, prebuilt) && !p.variantIsDisabled(ctx, prebuilt) {
740		return true
741	}
742
743	// If this is a mainline prebuilt, but has not been flagged, hide it.
744	if isMainlinePrebuilt(prebuilt) {
745		return false
746	}
747
748	// If the baseModuleName could not be found in the metadata module,
749	// fall back to the existing source vs prebuilt selection.
750	// TODO: Drop the fallback mechanisms
751
752	if p.variantIsDisabled(ctx, prebuilt) {
753		return false
754	}
755
756	// Skip prebuilt modules under unexported namespaces so that we won't
757	// end up shadowing non-prebuilt module when prebuilt module under same
758	// name happens to have a `Prefer` property set to true.
759	if ctx.Config().KatiEnabled() && !prebuilt.ExportedToMake() {
760		return false
761	}
762
763	// If source is not available or is disabled then always use the prebuilt.
764	if source == nil || !source.Enabled(ctx) {
765		return true
766	}
767
768	// TODO: use p.Properties.Name and ctx.ModuleDir to override preference
769	return p.properties.Prefer.GetOrDefault(ctx, false)
770}
771
772func (p *Prebuilt) SourceExists() bool {
773	return p.properties.SourceExists
774}
775