|  | // Copyright 2019 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 ( | 
|  | "fmt" | 
|  | "reflect" | 
|  |  | 
|  | "github.com/google/blueprint" | 
|  | "github.com/google/blueprint/proptools" | 
|  | ) | 
|  |  | 
|  | // This file implements support for automatically adding dependencies on any module referenced | 
|  | // with the ":module" module reference syntax in a property that is annotated with `android:"path"`. | 
|  | // The dependency is used by android.PathForModuleSrc to convert the module reference into the path | 
|  | // to the output file of the referenced module. | 
|  |  | 
|  | func registerPathDepsMutator(ctx RegisterMutatorsContext) { | 
|  | ctx.BottomUp("pathdeps", pathDepsMutator) | 
|  | } | 
|  |  | 
|  | // The pathDepsMutator automatically adds dependencies on any module that is listed with the | 
|  | // ":module" module reference syntax in a property that is tagged with `android:"path"`. | 
|  | func pathDepsMutator(ctx BottomUpMutatorContext) { | 
|  | if _, ok := ctx.Module().(DefaultsModule); ok { | 
|  | // Defaults modules shouldn't have dependencies added for path properties, they have already been | 
|  | // squashed into the real modules. | 
|  | return | 
|  | } | 
|  | if !ctx.Module().Enabled(ctx) { | 
|  | return | 
|  | } | 
|  | props := ctx.Module().base().GetProperties() | 
|  | addPathDepsForProps(ctx, props) | 
|  | } | 
|  |  | 
|  | func addPathDepsForProps(ctx BottomUpMutatorContext, props []interface{}) { | 
|  | // Iterate through each property struct of the module extracting the contents of all properties | 
|  | // tagged with `android:"path"` or one of the variant-specifying tags. | 
|  | var pathProperties []string | 
|  | var pathDeviceFirstProperties []string | 
|  | var pathDeviceFirstPrefer32Properties []string | 
|  | var pathDeviceFirstVendorProperties []string | 
|  | var pathDeviceFirstVendorSharedProperties []string | 
|  | var pathDeviceCommonProperties []string | 
|  | var pathCommonOsProperties []string | 
|  | for _, ps := range props { | 
|  | pathProperties = append(pathProperties, taggedPropertiesForPropertyStruct(ctx, ps, "path")...) | 
|  | pathDeviceFirstProperties = append(pathDeviceFirstProperties, taggedPropertiesForPropertyStruct(ctx, ps, "path_device_first")...) | 
|  | pathDeviceFirstPrefer32Properties = append(pathDeviceFirstPrefer32Properties, taggedPropertiesForPropertyStruct(ctx, ps, "path_device_first_prefer32")...) | 
|  | pathDeviceFirstVendorProperties = append(pathDeviceFirstVendorProperties, taggedPropertiesForPropertyStruct(ctx, ps, "path_device_first_vendor")...) | 
|  | pathDeviceFirstVendorSharedProperties = append(pathDeviceFirstVendorSharedProperties, taggedPropertiesForPropertyStruct(ctx, ps, "path_device_first_vendor_shared")...) | 
|  | pathDeviceCommonProperties = append(pathDeviceCommonProperties, taggedPropertiesForPropertyStruct(ctx, ps, "path_device_common")...) | 
|  | pathCommonOsProperties = append(pathCommonOsProperties, taggedPropertiesForPropertyStruct(ctx, ps, "path_common_os")...) | 
|  | } | 
|  |  | 
|  | // Remove duplicates to avoid multiple dependencies. | 
|  | pathProperties = FirstUniqueStrings(pathProperties) | 
|  | pathDeviceFirstProperties = FirstUniqueStrings(pathDeviceFirstProperties) | 
|  | pathDeviceFirstPrefer32Properties = FirstUniqueStrings(pathDeviceFirstPrefer32Properties) | 
|  | pathDeviceFirstVendorProperties = FirstUniqueStrings(pathDeviceFirstVendorProperties) | 
|  | pathDeviceFirstVendorSharedProperties = FirstUniqueStrings(pathDeviceFirstVendorSharedProperties) | 
|  | pathDeviceCommonProperties = FirstUniqueStrings(pathDeviceCommonProperties) | 
|  | pathCommonOsProperties = FirstUniqueStrings(pathCommonOsProperties) | 
|  |  | 
|  | // Add dependencies to anything that is a module reference. | 
|  | for _, s := range pathProperties { | 
|  | if m, t := SrcIsModuleWithTag(s); m != "" { | 
|  | ctx.AddDependency(ctx.Module(), sourceOrOutputDepTag(m, t), m) | 
|  | } | 
|  | } | 
|  | // For properties tagged "path_device_first", use the first arch device variant when adding | 
|  | // dependencies. This allows host modules to have some properties that add dependencies on | 
|  | // device modules. | 
|  | for _, s := range pathDeviceFirstProperties { | 
|  | if m, t := SrcIsModuleWithTag(s); m != "" { | 
|  | ctx.AddVariationDependencies(ctx.Config().AndroidFirstDeviceTarget.Variations(), sourceOrOutputDepTag(m, t), m) | 
|  | } | 
|  | } | 
|  | // properties tagged path_device_first_prefer32 get the first 32 bit target if one is available, | 
|  | // otherwise they use the first 64 bit target | 
|  | if len(pathDeviceFirstPrefer32Properties) > 0 { | 
|  | var targets []Target | 
|  | if ctx.Config().IgnorePrefer32OnDevice() { | 
|  | targets, _ = decodeMultilibTargets("first", ctx.Config().Targets[Android], false) | 
|  | } else { | 
|  | targets, _ = decodeMultilibTargets("first_prefer32", ctx.Config().Targets[Android], false) | 
|  | } | 
|  | if len(targets) == 0 { | 
|  | ctx.ModuleErrorf("Could not find a first_prefer32 target") | 
|  | } else { | 
|  | for _, s := range pathDeviceFirstPrefer32Properties { | 
|  | if m, t := SrcIsModuleWithTag(s); m != "" { | 
|  | ctx.AddVariationDependencies(targets[0].Variations(), sourceOrOutputDepTag(m, t), m) | 
|  | } | 
|  | } | 
|  | } | 
|  | } | 
|  | // path_device_first_vendor is path_device_first + vendor variation | 
|  | deviceFirstVendorVariations := ctx.Config().AndroidFirstDeviceTarget.Variations() | 
|  | deviceFirstVendorVariations = append(deviceFirstVendorVariations, | 
|  | blueprint.Variation{Mutator: "image", Variation: "vendor"}) | 
|  | for _, s := range pathDeviceFirstVendorProperties { | 
|  | if m, t := SrcIsModuleWithTag(s); m != "" { | 
|  | ctx.AddVariationDependencies(deviceFirstVendorVariations, sourceOrOutputDepTag(m, t), m) | 
|  | } | 
|  | } | 
|  | // path_device_first_vendor_shared is path_device_first_vendor + shared linkage variation | 
|  | deviceFirstVendorSharedVariations := append(deviceFirstVendorVariations, | 
|  | blueprint.Variation{Mutator: "link", Variation: "shared"}) | 
|  | for _, s := range pathDeviceFirstVendorSharedProperties { | 
|  | if m, t := SrcIsModuleWithTag(s); m != "" { | 
|  | ctx.AddVariationDependencies(deviceFirstVendorSharedVariations, sourceOrOutputDepTag(m, t), m) | 
|  | } | 
|  | } | 
|  | // properties tagged "path_device_common" get the device common variant | 
|  | for _, s := range pathDeviceCommonProperties { | 
|  | if m, t := SrcIsModuleWithTag(s); m != "" { | 
|  | ctx.AddVariationDependencies(ctx.Config().AndroidCommonTarget.Variations(), sourceOrOutputDepTag(m, t), m) | 
|  | } | 
|  | } | 
|  | // properties tagged "path_common_os" get the CommonOs variant | 
|  | for _, s := range pathCommonOsProperties { | 
|  | if m, t := SrcIsModuleWithTag(s); m != "" { | 
|  | ctx.AddVariationDependencies([]blueprint.Variation{ | 
|  | {Mutator: "os", Variation: "common_os"}, | 
|  | {Mutator: "arch", Variation: ""}, | 
|  | }, sourceOrOutputDepTag(m, t), m) | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | // taggedPropertiesForPropertyStruct uses the indexes of properties that are tagged with | 
|  | // android:"tagValue" to extract all their values from a property struct, returning them as a single | 
|  | // slice of strings. | 
|  | func taggedPropertiesForPropertyStruct(ctx BottomUpMutatorContext, ps interface{}, tagValue string) []string { | 
|  | v := reflect.ValueOf(ps) | 
|  | if v.Kind() != reflect.Ptr || v.Elem().Kind() != reflect.Struct { | 
|  | panic(fmt.Errorf("type %s is not a pointer to a struct", v.Type())) | 
|  | } | 
|  |  | 
|  | // If the property struct is a nil pointer it can't have any paths set in it. | 
|  | if v.IsNil() { | 
|  | return nil | 
|  | } | 
|  |  | 
|  | // v is now the reflect.Value for the concrete property struct. | 
|  | v = v.Elem() | 
|  |  | 
|  | // Get or create the list of indexes of properties that are tagged with `android:"path"`. | 
|  | pathPropertyIndexes := taggedPropertyIndexesForPropertyStruct(ps, tagValue) | 
|  |  | 
|  | var ret []string | 
|  |  | 
|  | for _, i := range pathPropertyIndexes { | 
|  | var values []reflect.Value | 
|  | fieldsByIndex(v, i, &values) | 
|  | for _, sv := range values { | 
|  | if !sv.IsValid() { | 
|  | // Skip properties inside a nil pointer. | 
|  | continue | 
|  | } | 
|  |  | 
|  | // If the field is a non-nil pointer step into it. | 
|  | if sv.Kind() == reflect.Ptr { | 
|  | if sv.IsNil() { | 
|  | continue | 
|  | } | 
|  | sv = sv.Elem() | 
|  | } | 
|  |  | 
|  | // Collect paths from all strings and slices of strings. | 
|  | switch sv.Kind() { | 
|  | case reflect.String: | 
|  | ret = append(ret, sv.String()) | 
|  | case reflect.Slice: | 
|  | ret = append(ret, sv.Interface().([]string)...) | 
|  | case reflect.Struct: | 
|  | intf := sv.Interface() | 
|  | if configurable, ok := intf.(proptools.Configurable[string]); ok { | 
|  | ret = append(ret, configurable.GetOrDefault(ctx, "")) | 
|  | } else if configurable, ok := intf.(proptools.Configurable[[]string]); ok { | 
|  | ret = append(ret, configurable.GetOrDefault(ctx, nil)...) | 
|  | } else { | 
|  | panic(fmt.Errorf(`field %s in type %s has tag android:"path" but is not a string or slice of strings, it is a %s`, | 
|  | v.Type().FieldByIndex(i).Name, v.Type(), sv.Type())) | 
|  | } | 
|  | default: | 
|  | panic(fmt.Errorf(`field %s in type %s has tag android:"path" but is not a string or slice of strings, it is a %s`, | 
|  | v.Type().FieldByIndex(i).Name, v.Type(), sv.Type())) | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | return ret | 
|  | } | 
|  |  | 
|  | // fieldsByIndex is similar to reflect.Value.FieldByIndex, but is more robust: it doesn't track | 
|  | // nil pointers and it returns multiple values when there's slice of struct. | 
|  | func fieldsByIndex(v reflect.Value, index []int, values *[]reflect.Value) { | 
|  | // leaf case | 
|  | if len(index) == 1 { | 
|  | if isSliceOfStruct(v) { | 
|  | for i := 0; i < v.Len(); i++ { | 
|  | *values = append(*values, v.Index(i).Field(index[0])) | 
|  | } | 
|  | } else { | 
|  | // Dereference it if it's a pointer. | 
|  | if v.Kind() == reflect.Ptr { | 
|  | if v.IsNil() { | 
|  | return | 
|  | } | 
|  | v = v.Elem() | 
|  | } | 
|  | *values = append(*values, v.Field(index[0])) | 
|  | } | 
|  | return | 
|  | } | 
|  |  | 
|  | // recursion | 
|  | if v.Kind() == reflect.Ptr { | 
|  | // don't track nil pointer | 
|  | if v.IsNil() { | 
|  | return | 
|  | } | 
|  | v = v.Elem() | 
|  | } else if isSliceOfStruct(v) { | 
|  | // do the recursion for all elements | 
|  | for i := 0; i < v.Len(); i++ { | 
|  | fieldsByIndex(v.Index(i).Field(index[0]), index[1:], values) | 
|  | } | 
|  | return | 
|  | } | 
|  | fieldsByIndex(v.Field(index[0]), index[1:], values) | 
|  | return | 
|  | } | 
|  |  | 
|  | func isSliceOfStruct(v reflect.Value) bool { | 
|  | return v.Kind() == reflect.Slice && v.Type().Elem().Kind() == reflect.Struct | 
|  | } | 
|  |  | 
|  | var pathPropertyIndexesCache OncePer | 
|  |  | 
|  | // taggedPropertyIndexesForPropertyStruct returns a list of all of the indexes of properties in | 
|  | // property struct type that are tagged with `android:"tagValue"`.  Each index is a []int suitable | 
|  | // for passing to reflect.Value.FieldByIndex.  The value is cached in a global cache by type and | 
|  | // tagValue. | 
|  | func taggedPropertyIndexesForPropertyStruct(ps interface{}, tagValue string) [][]int { | 
|  | type pathPropertyIndexesOnceKey struct { | 
|  | propStructType reflect.Type | 
|  | tagValue       string | 
|  | } | 
|  | key := NewCustomOnceKey(pathPropertyIndexesOnceKey{ | 
|  | propStructType: reflect.TypeOf(ps), | 
|  | tagValue:       tagValue, | 
|  | }) | 
|  | return pathPropertyIndexesCache.Once(key, func() interface{} { | 
|  | return proptools.PropertyIndexesWithTag(ps, "android", tagValue) | 
|  | }).([][]int) | 
|  | } |