| // Copyright 2019 The Go Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| package protodesc |
| |
| import ( |
| "fmt" |
| "os" |
| "sync" |
| |
| "google.golang.org/protobuf/internal/editiondefaults" |
| "google.golang.org/protobuf/internal/filedesc" |
| "google.golang.org/protobuf/proto" |
| "google.golang.org/protobuf/reflect/protoreflect" |
| "google.golang.org/protobuf/types/descriptorpb" |
| gofeaturespb "google.golang.org/protobuf/types/gofeaturespb" |
| ) |
| |
| var defaults = &descriptorpb.FeatureSetDefaults{} |
| var defaultsCacheMu sync.Mutex |
| var defaultsCache = make(map[filedesc.Edition]*descriptorpb.FeatureSet) |
| |
| func init() { |
| err := proto.Unmarshal(editiondefaults.Defaults, defaults) |
| if err != nil { |
| fmt.Fprintf(os.Stderr, "unmarshal editions defaults: %v\n", err) |
| os.Exit(1) |
| } |
| } |
| |
| func fromEditionProto(epb descriptorpb.Edition) filedesc.Edition { |
| return filedesc.Edition(epb) |
| } |
| |
| func toEditionProto(ed filedesc.Edition) descriptorpb.Edition { |
| switch ed { |
| case filedesc.EditionUnknown: |
| return descriptorpb.Edition_EDITION_UNKNOWN |
| case filedesc.EditionProto2: |
| return descriptorpb.Edition_EDITION_PROTO2 |
| case filedesc.EditionProto3: |
| return descriptorpb.Edition_EDITION_PROTO3 |
| case filedesc.Edition2023: |
| return descriptorpb.Edition_EDITION_2023 |
| default: |
| panic(fmt.Sprintf("unknown value for edition: %v", ed)) |
| } |
| } |
| |
| func getFeatureSetFor(ed filedesc.Edition) *descriptorpb.FeatureSet { |
| defaultsCacheMu.Lock() |
| defer defaultsCacheMu.Unlock() |
| if def, ok := defaultsCache[ed]; ok { |
| return def |
| } |
| edpb := toEditionProto(ed) |
| if defaults.GetMinimumEdition() > edpb || defaults.GetMaximumEdition() < edpb { |
| // This should never happen protodesc.(FileOptions).New would fail when |
| // initializing the file descriptor. |
| // This most likely means the embedded defaults were not updated. |
| fmt.Fprintf(os.Stderr, "internal error: unsupported edition %v (did you forget to update the embedded defaults (i.e. the bootstrap descriptor proto)?)\n", edpb) |
| os.Exit(1) |
| } |
| fsed := defaults.GetDefaults()[0] |
| // Using a linear search for now. |
| // Editions are guaranteed to be sorted and thus we could use a binary search. |
| // Given that there are only a handful of editions (with one more per year) |
| // there is not much reason to use a binary search. |
| for _, def := range defaults.GetDefaults() { |
| if def.GetEdition() <= edpb { |
| fsed = def |
| } else { |
| break |
| } |
| } |
| fs := proto.Clone(fsed.GetFixedFeatures()).(*descriptorpb.FeatureSet) |
| proto.Merge(fs, fsed.GetOverridableFeatures()) |
| defaultsCache[ed] = fs |
| return fs |
| } |
| |
| // mergeEditionFeatures merges the parent and child feature sets. This function |
| // should be used when initializing Go descriptors from descriptor protos which |
| // is why the parent is a filedesc.EditionsFeatures (Go representation) while |
| // the child is a descriptorproto.FeatureSet (protoc representation). |
| // Any feature set by the child overwrites what is set by the parent. |
| func mergeEditionFeatures(parentDesc protoreflect.Descriptor, child *descriptorpb.FeatureSet) filedesc.EditionFeatures { |
| var parentFS filedesc.EditionFeatures |
| switch p := parentDesc.(type) { |
| case *filedesc.File: |
| parentFS = p.L1.EditionFeatures |
| case *filedesc.Message: |
| parentFS = p.L1.EditionFeatures |
| default: |
| panic(fmt.Sprintf("unknown parent type %T", parentDesc)) |
| } |
| if child == nil { |
| return parentFS |
| } |
| if fp := child.FieldPresence; fp != nil { |
| parentFS.IsFieldPresence = *fp == descriptorpb.FeatureSet_LEGACY_REQUIRED || |
| *fp == descriptorpb.FeatureSet_EXPLICIT |
| parentFS.IsLegacyRequired = *fp == descriptorpb.FeatureSet_LEGACY_REQUIRED |
| } |
| if et := child.EnumType; et != nil { |
| parentFS.IsOpenEnum = *et == descriptorpb.FeatureSet_OPEN |
| } |
| |
| if rfe := child.RepeatedFieldEncoding; rfe != nil { |
| parentFS.IsPacked = *rfe == descriptorpb.FeatureSet_PACKED |
| } |
| |
| if utf8val := child.Utf8Validation; utf8val != nil { |
| parentFS.IsUTF8Validated = *utf8val == descriptorpb.FeatureSet_VERIFY |
| } |
| |
| if me := child.MessageEncoding; me != nil { |
| parentFS.IsDelimitedEncoded = *me == descriptorpb.FeatureSet_DELIMITED |
| } |
| |
| if jf := child.JsonFormat; jf != nil { |
| parentFS.IsJSONCompliant = *jf == descriptorpb.FeatureSet_ALLOW |
| } |
| |
| if goFeatures, ok := proto.GetExtension(child, gofeaturespb.E_Go).(*gofeaturespb.GoFeatures); ok && goFeatures != nil { |
| if luje := goFeatures.LegacyUnmarshalJsonEnum; luje != nil { |
| parentFS.GenerateLegacyUnmarshalJSON = *luje |
| } |
| } |
| |
| return parentFS |
| } |
| |
| // initFileDescFromFeatureSet initializes editions related fields in fd based |
| // on fs. If fs is nil it is assumed to be an empty featureset and all fields |
| // will be initialized with the appropriate default. fd.L1.Edition must be set |
| // before calling this function. |
| func initFileDescFromFeatureSet(fd *filedesc.File, fs *descriptorpb.FeatureSet) { |
| dfs := getFeatureSetFor(fd.L1.Edition) |
| // initialize the featureset with the defaults |
| fd.L1.EditionFeatures = mergeEditionFeatures(fd, dfs) |
| // overwrite any options explicitly specified |
| fd.L1.EditionFeatures = mergeEditionFeatures(fd, fs) |
| } |