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-rw-r--r--vendor/google.golang.org/protobuf/internal/filetype/build.go297
1 files changed, 297 insertions, 0 deletions
diff --git a/vendor/google.golang.org/protobuf/internal/filetype/build.go b/vendor/google.golang.org/protobuf/internal/filetype/build.go
new file mode 100644
index 000000000..0a0dd35de
--- /dev/null
+++ b/vendor/google.golang.org/protobuf/internal/filetype/build.go
@@ -0,0 +1,297 @@
+// 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 filetype provides functionality for wrapping descriptors
+// with Go type information.
+package filetype
+
+import (
+ "reflect"
+
+ "google.golang.org/protobuf/internal/descopts"
+ fdesc "google.golang.org/protobuf/internal/filedesc"
+ pimpl "google.golang.org/protobuf/internal/impl"
+ pref "google.golang.org/protobuf/reflect/protoreflect"
+ preg "google.golang.org/protobuf/reflect/protoregistry"
+)
+
+// Builder constructs type descriptors from a raw file descriptor
+// and associated Go types for each enum and message declaration.
+//
+//
+// Flattened Ordering
+//
+// The protobuf type system represents declarations as a tree. Certain nodes in
+// the tree require us to either associate it with a concrete Go type or to
+// resolve a dependency, which is information that must be provided separately
+// since it cannot be derived from the file descriptor alone.
+//
+// However, representing a tree as Go literals is difficult to simply do in a
+// space and time efficient way. Thus, we store them as a flattened list of
+// objects where the serialization order from the tree-based form is important.
+//
+// The "flattened ordering" is defined as a tree traversal of all enum, message,
+// extension, and service declarations using the following algorithm:
+//
+// def VisitFileDecls(fd):
+// for e in fd.Enums: yield e
+// for m in fd.Messages: yield m
+// for x in fd.Extensions: yield x
+// for s in fd.Services: yield s
+// for m in fd.Messages: yield from VisitMessageDecls(m)
+//
+// def VisitMessageDecls(md):
+// for e in md.Enums: yield e
+// for m in md.Messages: yield m
+// for x in md.Extensions: yield x
+// for m in md.Messages: yield from VisitMessageDecls(m)
+//
+// The traversal starts at the root file descriptor and yields each direct
+// declaration within each node before traversing into sub-declarations
+// that children themselves may have.
+type Builder struct {
+ // File is the underlying file descriptor builder.
+ File fdesc.Builder
+
+ // GoTypes is a unique set of the Go types for all declarations and
+ // dependencies. Each type is represented as a zero value of the Go type.
+ //
+ // Declarations are Go types generated for enums and messages directly
+ // declared (not publicly imported) in the proto source file.
+ // Messages for map entries are accounted for, but represented by nil.
+ // Enum declarations in "flattened ordering" come first, followed by
+ // message declarations in "flattened ordering".
+ //
+ // Dependencies are Go types for enums or messages referenced by
+ // message fields (excluding weak fields), for parent extended messages of
+ // extension fields, for enums or messages referenced by extension fields,
+ // and for input and output messages referenced by service methods.
+ // Dependencies must come after declarations, but the ordering of
+ // dependencies themselves is unspecified.
+ GoTypes []interface{}
+
+ // DependencyIndexes is an ordered list of indexes into GoTypes for the
+ // dependencies of messages, extensions, or services.
+ //
+ // There are 5 sub-lists in "flattened ordering" concatenated back-to-back:
+ // 0. Message field dependencies: list of the enum or message type
+ // referred to by every message field.
+ // 1. Extension field targets: list of the extended parent message of
+ // every extension.
+ // 2. Extension field dependencies: list of the enum or message type
+ // referred to by every extension field.
+ // 3. Service method inputs: list of the input message type
+ // referred to by every service method.
+ // 4. Service method outputs: list of the output message type
+ // referred to by every service method.
+ //
+ // The offset into DependencyIndexes for the start of each sub-list
+ // is appended to the end in reverse order.
+ DependencyIndexes []int32
+
+ // EnumInfos is a list of enum infos in "flattened ordering".
+ EnumInfos []pimpl.EnumInfo
+
+ // MessageInfos is a list of message infos in "flattened ordering".
+ // If provided, the GoType and PBType for each element is populated.
+ //
+ // Requirement: len(MessageInfos) == len(Build.Messages)
+ MessageInfos []pimpl.MessageInfo
+
+ // ExtensionInfos is a list of extension infos in "flattened ordering".
+ // Each element is initialized and registered with the protoregistry package.
+ //
+ // Requirement: len(LegacyExtensions) == len(Build.Extensions)
+ ExtensionInfos []pimpl.ExtensionInfo
+
+ // TypeRegistry is the registry to register each type descriptor.
+ // If nil, it uses protoregistry.GlobalTypes.
+ TypeRegistry interface {
+ RegisterMessage(pref.MessageType) error
+ RegisterEnum(pref.EnumType) error
+ RegisterExtension(pref.ExtensionType) error
+ }
+}
+
+// Out is the output of the builder.
+type Out struct {
+ File pref.FileDescriptor
+}
+
+func (tb Builder) Build() (out Out) {
+ // Replace the resolver with one that resolves dependencies by index,
+ // which is faster and more reliable than relying on the global registry.
+ if tb.File.FileRegistry == nil {
+ tb.File.FileRegistry = preg.GlobalFiles
+ }
+ tb.File.FileRegistry = &resolverByIndex{
+ goTypes: tb.GoTypes,
+ depIdxs: tb.DependencyIndexes,
+ fileRegistry: tb.File.FileRegistry,
+ }
+
+ // Initialize registry if unpopulated.
+ if tb.TypeRegistry == nil {
+ tb.TypeRegistry = preg.GlobalTypes
+ }
+
+ fbOut := tb.File.Build()
+ out.File = fbOut.File
+
+ // Process enums.
+ enumGoTypes := tb.GoTypes[:len(fbOut.Enums)]
+ if len(tb.EnumInfos) != len(fbOut.Enums) {
+ panic("mismatching enum lengths")
+ }
+ if len(fbOut.Enums) > 0 {
+ for i := range fbOut.Enums {
+ tb.EnumInfos[i] = pimpl.EnumInfo{
+ GoReflectType: reflect.TypeOf(enumGoTypes[i]),
+ Desc: &fbOut.Enums[i],
+ }
+ // Register enum types.
+ if err := tb.TypeRegistry.RegisterEnum(&tb.EnumInfos[i]); err != nil {
+ panic(err)
+ }
+ }
+ }
+
+ // Process messages.
+ messageGoTypes := tb.GoTypes[len(fbOut.Enums):][:len(fbOut.Messages)]
+ if len(tb.MessageInfos) != len(fbOut.Messages) {
+ panic("mismatching message lengths")
+ }
+ if len(fbOut.Messages) > 0 {
+ for i := range fbOut.Messages {
+ if messageGoTypes[i] == nil {
+ continue // skip map entry
+ }
+
+ tb.MessageInfos[i].GoReflectType = reflect.TypeOf(messageGoTypes[i])
+ tb.MessageInfos[i].Desc = &fbOut.Messages[i]
+
+ // Register message types.
+ if err := tb.TypeRegistry.RegisterMessage(&tb.MessageInfos[i]); err != nil {
+ panic(err)
+ }
+ }
+
+ // As a special-case for descriptor.proto,
+ // locally register concrete message type for the options.
+ if out.File.Path() == "google/protobuf/descriptor.proto" && out.File.Package() == "google.protobuf" {
+ for i := range fbOut.Messages {
+ switch fbOut.Messages[i].Name() {
+ case "FileOptions":
+ descopts.File = messageGoTypes[i].(pref.ProtoMessage)
+ case "EnumOptions":
+ descopts.Enum = messageGoTypes[i].(pref.ProtoMessage)
+ case "EnumValueOptions":
+ descopts.EnumValue = messageGoTypes[i].(pref.ProtoMessage)
+ case "MessageOptions":
+ descopts.Message = messageGoTypes[i].(pref.ProtoMessage)
+ case "FieldOptions":
+ descopts.Field = messageGoTypes[i].(pref.ProtoMessage)
+ case "OneofOptions":
+ descopts.Oneof = messageGoTypes[i].(pref.ProtoMessage)
+ case "ExtensionRangeOptions":
+ descopts.ExtensionRange = messageGoTypes[i].(pref.ProtoMessage)
+ case "ServiceOptions":
+ descopts.Service = messageGoTypes[i].(pref.ProtoMessage)
+ case "MethodOptions":
+ descopts.Method = messageGoTypes[i].(pref.ProtoMessage)
+ }
+ }
+ }
+ }
+
+ // Process extensions.
+ if len(tb.ExtensionInfos) != len(fbOut.Extensions) {
+ panic("mismatching extension lengths")
+ }
+ var depIdx int32
+ for i := range fbOut.Extensions {
+ // For enum and message kinds, determine the referent Go type so
+ // that we can construct their constructors.
+ const listExtDeps = 2
+ var goType reflect.Type
+ switch fbOut.Extensions[i].L1.Kind {
+ case pref.EnumKind:
+ j := depIdxs.Get(tb.DependencyIndexes, listExtDeps, depIdx)
+ goType = reflect.TypeOf(tb.GoTypes[j])
+ depIdx++
+ case pref.MessageKind, pref.GroupKind:
+ j := depIdxs.Get(tb.DependencyIndexes, listExtDeps, depIdx)
+ goType = reflect.TypeOf(tb.GoTypes[j])
+ depIdx++
+ default:
+ goType = goTypeForPBKind[fbOut.Extensions[i].L1.Kind]
+ }
+ if fbOut.Extensions[i].IsList() {
+ goType = reflect.SliceOf(goType)
+ }
+
+ pimpl.InitExtensionInfo(&tb.ExtensionInfos[i], &fbOut.Extensions[i], goType)
+
+ // Register extension types.
+ if err := tb.TypeRegistry.RegisterExtension(&tb.ExtensionInfos[i]); err != nil {
+ panic(err)
+ }
+ }
+
+ return out
+}
+
+var goTypeForPBKind = map[pref.Kind]reflect.Type{
+ pref.BoolKind: reflect.TypeOf(bool(false)),
+ pref.Int32Kind: reflect.TypeOf(int32(0)),
+ pref.Sint32Kind: reflect.TypeOf(int32(0)),
+ pref.Sfixed32Kind: reflect.TypeOf(int32(0)),
+ pref.Int64Kind: reflect.TypeOf(int64(0)),
+ pref.Sint64Kind: reflect.TypeOf(int64(0)),
+ pref.Sfixed64Kind: reflect.TypeOf(int64(0)),
+ pref.Uint32Kind: reflect.TypeOf(uint32(0)),
+ pref.Fixed32Kind: reflect.TypeOf(uint32(0)),
+ pref.Uint64Kind: reflect.TypeOf(uint64(0)),
+ pref.Fixed64Kind: reflect.TypeOf(uint64(0)),
+ pref.FloatKind: reflect.TypeOf(float32(0)),
+ pref.DoubleKind: reflect.TypeOf(float64(0)),
+ pref.StringKind: reflect.TypeOf(string("")),
+ pref.BytesKind: reflect.TypeOf([]byte(nil)),
+}
+
+type depIdxs []int32
+
+// Get retrieves the jth element of the ith sub-list.
+func (x depIdxs) Get(i, j int32) int32 {
+ return x[x[int32(len(x))-i-1]+j]
+}
+
+type (
+ resolverByIndex struct {
+ goTypes []interface{}
+ depIdxs depIdxs
+ fileRegistry
+ }
+ fileRegistry interface {
+ FindFileByPath(string) (pref.FileDescriptor, error)
+ FindDescriptorByName(pref.FullName) (pref.Descriptor, error)
+ RegisterFile(pref.FileDescriptor) error
+ }
+)
+
+func (r *resolverByIndex) FindEnumByIndex(i, j int32, es []fdesc.Enum, ms []fdesc.Message) pref.EnumDescriptor {
+ if depIdx := int(r.depIdxs.Get(i, j)); int(depIdx) < len(es)+len(ms) {
+ return &es[depIdx]
+ } else {
+ return pimpl.Export{}.EnumDescriptorOf(r.goTypes[depIdx])
+ }
+}
+
+func (r *resolverByIndex) FindMessageByIndex(i, j int32, es []fdesc.Enum, ms []fdesc.Message) pref.MessageDescriptor {
+ if depIdx := int(r.depIdxs.Get(i, j)); depIdx < len(es)+len(ms) {
+ return &ms[depIdx-len(es)]
+ } else {
+ return pimpl.Export{}.MessageDescriptorOf(r.goTypes[depIdx])
+ }
+}