podman

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// Go support for Protocol Buffers - Google's data interchange format
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//
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// Copyright 2011 The Go Authors.  All rights reserved.
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// https://github.com/golang/protobuf
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//
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// Redistribution and use in source and binary forms, with or without
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// modification, are permitted provided that the following conditions are
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// met:
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//
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//     * Redistributions of source code must retain the above copyright
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// notice, this list of conditions and the following disclaimer.
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//     * Redistributions in binary form must reproduce the above
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// copyright notice, this list of conditions and the following disclaimer
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// in the documentation and/or other materials provided with the
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// distribution.
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//     * Neither the name of Google Inc. nor the names of its
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// contributors may be used to endorse or promote products derived from
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// this software without specific prior written permission.
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//
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// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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// Protocol buffer deep copy and merge.
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// TODO: RawMessage.
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package proto
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import (
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	"fmt"
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	"log"
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	"reflect"
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	"strings"
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)
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// Clone returns a deep copy of a protocol buffer.
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func Clone(src Message) Message {
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	in := reflect.ValueOf(src)
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	if in.IsNil() {
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		return src
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	}
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	out := reflect.New(in.Type().Elem())
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	dst := out.Interface().(Message)
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	Merge(dst, src)
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	return dst
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}
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// Merger is the interface representing objects that can merge messages of the same type.
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type Merger interface {
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	// Merge merges src into this message.
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	// Required and optional fields that are set in src will be set to that value in dst.
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	// Elements of repeated fields will be appended.
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	//
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	// Merge may panic if called with a different argument type than the receiver.
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	Merge(src Message)
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}
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// generatedMerger is the custom merge method that generated protos will have.
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// We must add this method since a generate Merge method will conflict with
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// many existing protos that have a Merge data field already defined.
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type generatedMerger interface {
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	XXX_Merge(src Message)
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}
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// Merge merges src into dst.
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// Required and optional fields that are set in src will be set to that value in dst.
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// Elements of repeated fields will be appended.
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// Merge panics if src and dst are not the same type, or if dst is nil.
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func Merge(dst, src Message) {
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	if m, ok := dst.(Merger); ok {
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		m.Merge(src)
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		return
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	}
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	in := reflect.ValueOf(src)
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	out := reflect.ValueOf(dst)
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	if out.IsNil() {
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		panic("proto: nil destination")
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	}
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	if in.Type() != out.Type() {
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		panic(fmt.Sprintf("proto.Merge(%T, %T) type mismatch", dst, src))
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	}
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	if in.IsNil() {
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		return // Merge from nil src is a noop
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	}
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	if m, ok := dst.(generatedMerger); ok {
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		m.XXX_Merge(src)
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		return
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	}
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	mergeStruct(out.Elem(), in.Elem())
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}
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func mergeStruct(out, in reflect.Value) {
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	sprop := GetProperties(in.Type())
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	for i := 0; i < in.NumField(); i++ {
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		f := in.Type().Field(i)
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		if strings.HasPrefix(f.Name, "XXX_") {
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			continue
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		}
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		mergeAny(out.Field(i), in.Field(i), false, sprop.Prop[i])
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	}
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	if emIn, ok := in.Addr().Interface().(extensionsBytes); ok {
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		emOut := out.Addr().Interface().(extensionsBytes)
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		bIn := emIn.GetExtensions()
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		bOut := emOut.GetExtensions()
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		*bOut = append(*bOut, *bIn...)
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	} else if emIn, err := extendable(in.Addr().Interface()); err == nil {
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		emOut, _ := extendable(out.Addr().Interface())
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		mIn, muIn := emIn.extensionsRead()
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		if mIn != nil {
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			mOut := emOut.extensionsWrite()
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			muIn.Lock()
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			mergeExtension(mOut, mIn)
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			muIn.Unlock()
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		}
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	}
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	uf := in.FieldByName("XXX_unrecognized")
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	if !uf.IsValid() {
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		return
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	}
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	uin := uf.Bytes()
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	if len(uin) > 0 {
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		out.FieldByName("XXX_unrecognized").SetBytes(append([]byte(nil), uin...))
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	}
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}
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// mergeAny performs a merge between two values of the same type.
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// viaPtr indicates whether the values were indirected through a pointer (implying proto2).
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// prop is set if this is a struct field (it may be nil).
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func mergeAny(out, in reflect.Value, viaPtr bool, prop *Properties) {
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	if in.Type() == protoMessageType {
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		if !in.IsNil() {
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			if out.IsNil() {
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				out.Set(reflect.ValueOf(Clone(in.Interface().(Message))))
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			} else {
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				Merge(out.Interface().(Message), in.Interface().(Message))
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			}
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		}
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		return
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	}
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	switch in.Kind() {
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	case reflect.Bool, reflect.Float32, reflect.Float64, reflect.Int32, reflect.Int64,
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		reflect.String, reflect.Uint32, reflect.Uint64:
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		if !viaPtr && isProto3Zero(in) {
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			return
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		}
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		out.Set(in)
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	case reflect.Interface:
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		// Probably a oneof field; copy non-nil values.
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		if in.IsNil() {
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			return
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		}
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		// Allocate destination if it is not set, or set to a different type.
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		// Otherwise we will merge as normal.
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		if out.IsNil() || out.Elem().Type() != in.Elem().Type() {
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			out.Set(reflect.New(in.Elem().Elem().Type())) // interface -> *T -> T -> new(T)
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		}
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		mergeAny(out.Elem(), in.Elem(), false, nil)
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	case reflect.Map:
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		if in.Len() == 0 {
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			return
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		}
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		if out.IsNil() {
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			out.Set(reflect.MakeMap(in.Type()))
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		}
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		// For maps with value types of *T or []byte we need to deep copy each value.
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		elemKind := in.Type().Elem().Kind()
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		for _, key := range in.MapKeys() {
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			var val reflect.Value
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			switch elemKind {
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			case reflect.Ptr:
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				val = reflect.New(in.Type().Elem().Elem())
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				mergeAny(val, in.MapIndex(key), false, nil)
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			case reflect.Slice:
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				val = in.MapIndex(key)
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				val = reflect.ValueOf(append([]byte{}, val.Bytes()...))
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			default:
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				val = in.MapIndex(key)
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			}
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			out.SetMapIndex(key, val)
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		}
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	case reflect.Ptr:
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		if in.IsNil() {
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			return
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		}
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		if out.IsNil() {
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			out.Set(reflect.New(in.Elem().Type()))
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		}
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		mergeAny(out.Elem(), in.Elem(), true, nil)
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	case reflect.Slice:
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		if in.IsNil() {
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			return
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		}
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		if in.Type().Elem().Kind() == reflect.Uint8 {
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			// []byte is a scalar bytes field, not a repeated field.
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			// Edge case: if this is in a proto3 message, a zero length
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			// bytes field is considered the zero value, and should not
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			// be merged.
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			if prop != nil && prop.proto3 && in.Len() == 0 {
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				return
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			}
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			// Make a deep copy.
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			// Append to []byte{} instead of []byte(nil) so that we never end up
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			// with a nil result.
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			out.SetBytes(append([]byte{}, in.Bytes()...))
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			return
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		}
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		n := in.Len()
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		if out.IsNil() {
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			out.Set(reflect.MakeSlice(in.Type(), 0, n))
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		}
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		switch in.Type().Elem().Kind() {
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		case reflect.Bool, reflect.Float32, reflect.Float64, reflect.Int32, reflect.Int64,
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			reflect.String, reflect.Uint32, reflect.Uint64:
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			out.Set(reflect.AppendSlice(out, in))
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		default:
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			for i := 0; i < n; i++ {
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				x := reflect.Indirect(reflect.New(in.Type().Elem()))
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				mergeAny(x, in.Index(i), false, nil)
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				out.Set(reflect.Append(out, x))
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			}
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		}
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	case reflect.Struct:
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		mergeStruct(out, in)
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	default:
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		// unknown type, so not a protocol buffer
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		log.Printf("proto: don't know how to copy %v", in)
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	}
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}
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func mergeExtension(out, in map[int32]Extension) {
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	for extNum, eIn := range in {
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		eOut := Extension{desc: eIn.desc}
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		if eIn.value != nil {
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			v := reflect.New(reflect.TypeOf(eIn.value)).Elem()
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			mergeAny(v, reflect.ValueOf(eIn.value), false, nil)
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			eOut.value = v.Interface()
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		}
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		if eIn.enc != nil {
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			eOut.enc = make([]byte, len(eIn.enc))
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			copy(eOut.enc, eIn.enc)
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		}
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		out[extNum] = eOut
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	}
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}
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