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-rw-r--r--vendor/google.golang.org/protobuf/internal/impl/message.go215
1 files changed, 215 insertions, 0 deletions
diff --git a/vendor/google.golang.org/protobuf/internal/impl/message.go b/vendor/google.golang.org/protobuf/internal/impl/message.go
new file mode 100644
index 000000000..7dd994bd9
--- /dev/null
+++ b/vendor/google.golang.org/protobuf/internal/impl/message.go
@@ -0,0 +1,215 @@
+// Copyright 2018 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 impl
+
+import (
+ "fmt"
+ "reflect"
+ "strconv"
+ "strings"
+ "sync"
+ "sync/atomic"
+
+ "google.golang.org/protobuf/internal/genname"
+ "google.golang.org/protobuf/reflect/protoreflect"
+ pref "google.golang.org/protobuf/reflect/protoreflect"
+)
+
+// MessageInfo provides protobuf related functionality for a given Go type
+// that represents a message. A given instance of MessageInfo is tied to
+// exactly one Go type, which must be a pointer to a struct type.
+//
+// The exported fields must be populated before any methods are called
+// and cannot be mutated after set.
+type MessageInfo struct {
+ // GoReflectType is the underlying message Go type and must be populated.
+ GoReflectType reflect.Type // pointer to struct
+
+ // Desc is the underlying message descriptor type and must be populated.
+ Desc pref.MessageDescriptor
+
+ // Exporter must be provided in a purego environment in order to provide
+ // access to unexported fields.
+ Exporter exporter
+
+ // OneofWrappers is list of pointers to oneof wrapper struct types.
+ OneofWrappers []interface{}
+
+ initMu sync.Mutex // protects all unexported fields
+ initDone uint32
+
+ reflectMessageInfo // for reflection implementation
+ coderMessageInfo // for fast-path method implementations
+}
+
+// exporter is a function that returns a reference to the ith field of v,
+// where v is a pointer to a struct. It returns nil if it does not support
+// exporting the requested field (e.g., already exported).
+type exporter func(v interface{}, i int) interface{}
+
+// getMessageInfo returns the MessageInfo for any message type that
+// is generated by our implementation of protoc-gen-go (for v2 and on).
+// If it is unable to obtain a MessageInfo, it returns nil.
+func getMessageInfo(mt reflect.Type) *MessageInfo {
+ m, ok := reflect.Zero(mt).Interface().(pref.ProtoMessage)
+ if !ok {
+ return nil
+ }
+ mr, ok := m.ProtoReflect().(interface{ ProtoMessageInfo() *MessageInfo })
+ if !ok {
+ return nil
+ }
+ return mr.ProtoMessageInfo()
+}
+
+func (mi *MessageInfo) init() {
+ // This function is called in the hot path. Inline the sync.Once logic,
+ // since allocating a closure for Once.Do is expensive.
+ // Keep init small to ensure that it can be inlined.
+ if atomic.LoadUint32(&mi.initDone) == 0 {
+ mi.initOnce()
+ }
+}
+
+func (mi *MessageInfo) initOnce() {
+ mi.initMu.Lock()
+ defer mi.initMu.Unlock()
+ if mi.initDone == 1 {
+ return
+ }
+
+ t := mi.GoReflectType
+ if t.Kind() != reflect.Ptr && t.Elem().Kind() != reflect.Struct {
+ panic(fmt.Sprintf("got %v, want *struct kind", t))
+ }
+ t = t.Elem()
+
+ si := mi.makeStructInfo(t)
+ mi.makeReflectFuncs(t, si)
+ mi.makeCoderMethods(t, si)
+
+ atomic.StoreUint32(&mi.initDone, 1)
+}
+
+// getPointer returns the pointer for a message, which should be of
+// the type of the MessageInfo. If the message is of a different type,
+// it returns ok==false.
+func (mi *MessageInfo) getPointer(m pref.Message) (p pointer, ok bool) {
+ switch m := m.(type) {
+ case *messageState:
+ return m.pointer(), m.messageInfo() == mi
+ case *messageReflectWrapper:
+ return m.pointer(), m.messageInfo() == mi
+ }
+ return pointer{}, false
+}
+
+type (
+ SizeCache = int32
+ WeakFields = map[int32]protoreflect.ProtoMessage
+ UnknownFields = []byte
+ ExtensionFields = map[int32]ExtensionField
+)
+
+var (
+ sizecacheType = reflect.TypeOf(SizeCache(0))
+ weakFieldsType = reflect.TypeOf(WeakFields(nil))
+ unknownFieldsType = reflect.TypeOf(UnknownFields(nil))
+ extensionFieldsType = reflect.TypeOf(ExtensionFields(nil))
+)
+
+type structInfo struct {
+ sizecacheOffset offset
+ weakOffset offset
+ unknownOffset offset
+ extensionOffset offset
+
+ fieldsByNumber map[pref.FieldNumber]reflect.StructField
+ oneofsByName map[pref.Name]reflect.StructField
+ oneofWrappersByType map[reflect.Type]pref.FieldNumber
+ oneofWrappersByNumber map[pref.FieldNumber]reflect.Type
+}
+
+func (mi *MessageInfo) makeStructInfo(t reflect.Type) structInfo {
+ si := structInfo{
+ sizecacheOffset: invalidOffset,
+ weakOffset: invalidOffset,
+ unknownOffset: invalidOffset,
+ extensionOffset: invalidOffset,
+
+ fieldsByNumber: map[pref.FieldNumber]reflect.StructField{},
+ oneofsByName: map[pref.Name]reflect.StructField{},
+ oneofWrappersByType: map[reflect.Type]pref.FieldNumber{},
+ oneofWrappersByNumber: map[pref.FieldNumber]reflect.Type{},
+ }
+
+fieldLoop:
+ for i := 0; i < t.NumField(); i++ {
+ switch f := t.Field(i); f.Name {
+ case genname.SizeCache, genname.SizeCacheA:
+ if f.Type == sizecacheType {
+ si.sizecacheOffset = offsetOf(f, mi.Exporter)
+ }
+ case genname.WeakFields, genname.WeakFieldsA:
+ if f.Type == weakFieldsType {
+ si.weakOffset = offsetOf(f, mi.Exporter)
+ }
+ case genname.UnknownFields, genname.UnknownFieldsA:
+ if f.Type == unknownFieldsType {
+ si.unknownOffset = offsetOf(f, mi.Exporter)
+ }
+ case genname.ExtensionFields, genname.ExtensionFieldsA, genname.ExtensionFieldsB:
+ if f.Type == extensionFieldsType {
+ si.extensionOffset = offsetOf(f, mi.Exporter)
+ }
+ default:
+ for _, s := range strings.Split(f.Tag.Get("protobuf"), ",") {
+ if len(s) > 0 && strings.Trim(s, "0123456789") == "" {
+ n, _ := strconv.ParseUint(s, 10, 64)
+ si.fieldsByNumber[pref.FieldNumber(n)] = f
+ continue fieldLoop
+ }
+ }
+ if s := f.Tag.Get("protobuf_oneof"); len(s) > 0 {
+ si.oneofsByName[pref.Name(s)] = f
+ continue fieldLoop
+ }
+ }
+ }
+
+ // Derive a mapping of oneof wrappers to fields.
+ oneofWrappers := mi.OneofWrappers
+ for _, method := range []string{"XXX_OneofFuncs", "XXX_OneofWrappers"} {
+ if fn, ok := reflect.PtrTo(t).MethodByName(method); ok {
+ for _, v := range fn.Func.Call([]reflect.Value{reflect.Zero(fn.Type.In(0))}) {
+ if vs, ok := v.Interface().([]interface{}); ok {
+ oneofWrappers = vs
+ }
+ }
+ }
+ }
+ for _, v := range oneofWrappers {
+ tf := reflect.TypeOf(v).Elem()
+ f := tf.Field(0)
+ for _, s := range strings.Split(f.Tag.Get("protobuf"), ",") {
+ if len(s) > 0 && strings.Trim(s, "0123456789") == "" {
+ n, _ := strconv.ParseUint(s, 10, 64)
+ si.oneofWrappersByType[tf] = pref.FieldNumber(n)
+ si.oneofWrappersByNumber[pref.FieldNumber(n)] = tf
+ break
+ }
+ }
+ }
+
+ return si
+}
+
+func (mi *MessageInfo) New() protoreflect.Message {
+ return mi.MessageOf(reflect.New(mi.GoReflectType.Elem()).Interface())
+}
+func (mi *MessageInfo) Zero() protoreflect.Message {
+ return mi.MessageOf(reflect.Zero(mi.GoReflectType).Interface())
+}
+func (mi *MessageInfo) Descriptor() protoreflect.MessageDescriptor { return mi.Desc }