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-rw-r--r--vendor/github.com/golang/protobuf/proto/discard.go350
1 files changed, 350 insertions, 0 deletions
diff --git a/vendor/github.com/golang/protobuf/proto/discard.go b/vendor/github.com/golang/protobuf/proto/discard.go
new file mode 100644
index 0000000..dea2617
--- /dev/null
+++ b/vendor/github.com/golang/protobuf/proto/discard.go
@@ -0,0 +1,350 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2017 The Go Authors. All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+import (
+ "fmt"
+ "reflect"
+ "strings"
+ "sync"
+ "sync/atomic"
+)
+
+type generatedDiscarder interface {
+ XXX_DiscardUnknown()
+}
+
+// DiscardUnknown recursively discards all unknown fields from this message
+// and all embedded messages.
+//
+// When unmarshaling a message with unrecognized fields, the tags and values
+// of such fields are preserved in the Message. This allows a later call to
+// marshal to be able to produce a message that continues to have those
+// unrecognized fields. To avoid this, DiscardUnknown is used to
+// explicitly clear the unknown fields after unmarshaling.
+//
+// For proto2 messages, the unknown fields of message extensions are only
+// discarded from messages that have been accessed via GetExtension.
+func DiscardUnknown(m Message) {
+ if m, ok := m.(generatedDiscarder); ok {
+ m.XXX_DiscardUnknown()
+ return
+ }
+ // TODO: Dynamically populate a InternalMessageInfo for legacy messages,
+ // but the master branch has no implementation for InternalMessageInfo,
+ // so it would be more work to replicate that approach.
+ discardLegacy(m)
+}
+
+// DiscardUnknown recursively discards all unknown fields.
+func (a *InternalMessageInfo) DiscardUnknown(m Message) {
+ di := atomicLoadDiscardInfo(&a.discard)
+ if di == nil {
+ di = getDiscardInfo(reflect.TypeOf(m).Elem())
+ atomicStoreDiscardInfo(&a.discard, di)
+ }
+ di.discard(toPointer(&m))
+}
+
+type discardInfo struct {
+ typ reflect.Type
+
+ initialized int32 // 0: only typ is valid, 1: everything is valid
+ lock sync.Mutex
+
+ fields []discardFieldInfo
+ unrecognized field
+}
+
+type discardFieldInfo struct {
+ field field // Offset of field, guaranteed to be valid
+ discard func(src pointer)
+}
+
+var (
+ discardInfoMap = map[reflect.Type]*discardInfo{}
+ discardInfoLock sync.Mutex
+)
+
+func getDiscardInfo(t reflect.Type) *discardInfo {
+ discardInfoLock.Lock()
+ defer discardInfoLock.Unlock()
+ di := discardInfoMap[t]
+ if di == nil {
+ di = &discardInfo{typ: t}
+ discardInfoMap[t] = di
+ }
+ return di
+}
+
+func (di *discardInfo) discard(src pointer) {
+ if src.isNil() {
+ return // Nothing to do.
+ }
+
+ if atomic.LoadInt32(&di.initialized) == 0 {
+ di.computeDiscardInfo()
+ }
+
+ for _, fi := range di.fields {
+ sfp := src.offset(fi.field)
+ fi.discard(sfp)
+ }
+
+ // For proto2 messages, only discard unknown fields in message extensions
+ // that have been accessed via GetExtension.
+ if em, err := extendable(src.asPointerTo(di.typ).Interface()); err == nil {
+ // Ignore lock since DiscardUnknown is not concurrency safe.
+ emm, _ := em.extensionsRead()
+ for _, mx := range emm {
+ if m, ok := mx.value.(Message); ok {
+ DiscardUnknown(m)
+ }
+ }
+ }
+
+ if di.unrecognized.IsValid() {
+ *src.offset(di.unrecognized).toBytes() = nil
+ }
+}
+
+func (di *discardInfo) computeDiscardInfo() {
+ di.lock.Lock()
+ defer di.lock.Unlock()
+ if di.initialized != 0 {
+ return
+ }
+ t := di.typ
+ n := t.NumField()
+
+ for i := 0; i < n; i++ {
+ f := t.Field(i)
+ if strings.HasPrefix(f.Name, "XXX_") {
+ continue
+ }
+
+ dfi := discardFieldInfo{field: toField(&f)}
+ tf := f.Type
+
+ // Unwrap tf to get its most basic type.
+ var isPointer, isSlice bool
+ if tf.Kind() == reflect.Slice && tf.Elem().Kind() != reflect.Uint8 {
+ isSlice = true
+ tf = tf.Elem()
+ }
+ if tf.Kind() == reflect.Ptr {
+ isPointer = true
+ tf = tf.Elem()
+ }
+ if isPointer && isSlice && tf.Kind() != reflect.Struct {
+ panic(fmt.Sprintf("%v.%s cannot be a slice of pointers to primitive types", t, f.Name))
+ }
+
+ switch tf.Kind() {
+ case reflect.Struct:
+ switch {
+ case !isPointer:
+ panic(fmt.Sprintf("%v.%s cannot be a direct struct value", t, f.Name))
+ case isSlice: // E.g., []*pb.T
+ di := getDiscardInfo(tf)
+ dfi.discard = func(src pointer) {
+ sps := src.getPointerSlice()
+ for _, sp := range sps {
+ if !sp.isNil() {
+ di.discard(sp)
+ }
+ }
+ }
+ default: // E.g., *pb.T
+ di := getDiscardInfo(tf)
+ dfi.discard = func(src pointer) {
+ sp := src.getPointer()
+ if !sp.isNil() {
+ di.discard(sp)
+ }
+ }
+ }
+ case reflect.Map:
+ switch {
+ case isPointer || isSlice:
+ panic(fmt.Sprintf("%v.%s cannot be a pointer to a map or a slice of map values", t, f.Name))
+ default: // E.g., map[K]V
+ if tf.Elem().Kind() == reflect.Ptr { // Proto struct (e.g., *T)
+ dfi.discard = func(src pointer) {
+ sm := src.asPointerTo(tf).Elem()
+ if sm.Len() == 0 {
+ return
+ }
+ for _, key := range sm.MapKeys() {
+ val := sm.MapIndex(key)
+ DiscardUnknown(val.Interface().(Message))
+ }
+ }
+ } else {
+ dfi.discard = func(pointer) {} // Noop
+ }
+ }
+ case reflect.Interface:
+ // Must be oneof field.
+ switch {
+ case isPointer || isSlice:
+ panic(fmt.Sprintf("%v.%s cannot be a pointer to a interface or a slice of interface values", t, f.Name))
+ default: // E.g., interface{}
+ // TODO: Make this faster?
+ dfi.discard = func(src pointer) {
+ su := src.asPointerTo(tf).Elem()
+ if !su.IsNil() {
+ sv := su.Elem().Elem().Field(0)
+ if sv.Kind() == reflect.Ptr && sv.IsNil() {
+ return
+ }
+ switch sv.Type().Kind() {
+ case reflect.Ptr: // Proto struct (e.g., *T)
+ DiscardUnknown(sv.Interface().(Message))
+ }
+ }
+ }
+ }
+ default:
+ continue
+ }
+ di.fields = append(di.fields, dfi)
+ }
+
+ di.unrecognized = invalidField
+ if f, ok := t.FieldByName("XXX_unrecognized"); ok {
+ if f.Type != reflect.TypeOf([]byte{}) {
+ panic("expected XXX_unrecognized to be of type []byte")
+ }
+ di.unrecognized = toField(&f)
+ }
+
+ atomic.StoreInt32(&di.initialized, 1)
+}
+
+func discardLegacy(m Message) {
+ v := reflect.ValueOf(m)
+ if v.Kind() != reflect.Ptr || v.IsNil() {
+ return
+ }
+ v = v.Elem()
+ if v.Kind() != reflect.Struct {
+ return
+ }
+ t := v.Type()
+
+ for i := 0; i < v.NumField(); i++ {
+ f := t.Field(i)
+ if strings.HasPrefix(f.Name, "XXX_") {
+ continue
+ }
+ vf := v.Field(i)
+ tf := f.Type
+
+ // Unwrap tf to get its most basic type.
+ var isPointer, isSlice bool
+ if tf.Kind() == reflect.Slice && tf.Elem().Kind() != reflect.Uint8 {
+ isSlice = true
+ tf = tf.Elem()
+ }
+ if tf.Kind() == reflect.Ptr {
+ isPointer = true
+ tf = tf.Elem()
+ }
+ if isPointer && isSlice && tf.Kind() != reflect.Struct {
+ panic(fmt.Sprintf("%T.%s cannot be a slice of pointers to primitive types", m, f.Name))
+ }
+
+ switch tf.Kind() {
+ case reflect.Struct:
+ switch {
+ case !isPointer:
+ panic(fmt.Sprintf("%T.%s cannot be a direct struct value", m, f.Name))
+ case isSlice: // E.g., []*pb.T
+ for j := 0; j < vf.Len(); j++ {
+ discardLegacy(vf.Index(j).Interface().(Message))
+ }
+ default: // E.g., *pb.T
+ discardLegacy(vf.Interface().(Message))
+ }
+ case reflect.Map:
+ switch {
+ case isPointer || isSlice:
+ panic(fmt.Sprintf("%T.%s cannot be a pointer to a map or a slice of map values", m, f.Name))
+ default: // E.g., map[K]V
+ tv := vf.Type().Elem()
+ if tv.Kind() == reflect.Ptr && tv.Implements(protoMessageType) { // Proto struct (e.g., *T)
+ for _, key := range vf.MapKeys() {
+ val := vf.MapIndex(key)
+ discardLegacy(val.Interface().(Message))
+ }
+ }
+ }
+ case reflect.Interface:
+ // Must be oneof field.
+ switch {
+ case isPointer || isSlice:
+ panic(fmt.Sprintf("%T.%s cannot be a pointer to a interface or a slice of interface values", m, f.Name))
+ default: // E.g., test_proto.isCommunique_Union interface
+ if !vf.IsNil() && f.Tag.Get("protobuf_oneof") != "" {
+ vf = vf.Elem() // E.g., *test_proto.Communique_Msg
+ if !vf.IsNil() {
+ vf = vf.Elem() // E.g., test_proto.Communique_Msg
+ vf = vf.Field(0) // E.g., Proto struct (e.g., *T) or primitive value
+ if vf.Kind() == reflect.Ptr {
+ discardLegacy(vf.Interface().(Message))
+ }
+ }
+ }
+ }
+ }
+ }
+
+ if vf := v.FieldByName("XXX_unrecognized"); vf.IsValid() {
+ if vf.Type() != reflect.TypeOf([]byte{}) {
+ panic("expected XXX_unrecognized to be of type []byte")
+ }
+ vf.Set(reflect.ValueOf([]byte(nil)))
+ }
+
+ // For proto2 messages, only discard unknown fields in message extensions
+ // that have been accessed via GetExtension.
+ if em, err := extendable(m); err == nil {
+ // Ignore lock since discardLegacy is not concurrency safe.
+ emm, _ := em.extensionsRead()
+ for _, mx := range emm {
+ if m, ok := mx.value.(Message); ok {
+ discardLegacy(m)
+ }
+ }
+ }
+}