minio/vendor/github.com/golang/protobuf/proto/table_merge.go
Nitish Tiwari 2aa18cafc6 Update federation target to etcd/clientv3 (#6119)
With CoreDNS now supporting etcdv3 as the DNS backend, we
can update our federation target to etcdv3. Users will now be
able to use etcdv3 server as the federation backbone.

Minio will update bucket data to etcdv3 and CoreDNS can pick
that data up and serve it as bucket style DNS path.
2018-07-12 14:12:40 -07:00

655 lines
17 KiB
Go

// Go support for Protocol Buffers - Google's data interchange format
//
// Copyright 2016 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"
)
// Merge merges the src message into dst.
// This assumes that dst and src of the same type and are non-nil.
func (a *InternalMessageInfo) Merge(dst, src Message) {
mi := atomicLoadMergeInfo(&a.merge)
if mi == nil {
mi = getMergeInfo(reflect.TypeOf(dst).Elem())
atomicStoreMergeInfo(&a.merge, mi)
}
mi.merge(toPointer(&dst), toPointer(&src))
}
type mergeInfo struct {
typ reflect.Type
initialized int32 // 0: only typ is valid, 1: everything is valid
lock sync.Mutex
fields []mergeFieldInfo
unrecognized field // Offset of XXX_unrecognized
}
type mergeFieldInfo struct {
field field // Offset of field, guaranteed to be valid
// isPointer reports whether the value in the field is a pointer.
// This is true for the following situations:
// * Pointer to struct
// * Pointer to basic type (proto2 only)
// * Slice (first value in slice header is a pointer)
// * String (first value in string header is a pointer)
isPointer bool
// basicWidth reports the width of the field assuming that it is directly
// embedded in the struct (as is the case for basic types in proto3).
// The possible values are:
// 0: invalid
// 1: bool
// 4: int32, uint32, float32
// 8: int64, uint64, float64
basicWidth int
// Where dst and src are pointers to the types being merged.
merge func(dst, src pointer)
}
var (
mergeInfoMap = map[reflect.Type]*mergeInfo{}
mergeInfoLock sync.Mutex
)
func getMergeInfo(t reflect.Type) *mergeInfo {
mergeInfoLock.Lock()
defer mergeInfoLock.Unlock()
mi := mergeInfoMap[t]
if mi == nil {
mi = &mergeInfo{typ: t}
mergeInfoMap[t] = mi
}
return mi
}
// merge merges src into dst assuming they are both of type *mi.typ.
func (mi *mergeInfo) merge(dst, src pointer) {
if dst.isNil() {
panic("proto: nil destination")
}
if src.isNil() {
return // Nothing to do.
}
if atomic.LoadInt32(&mi.initialized) == 0 {
mi.computeMergeInfo()
}
for _, fi := range mi.fields {
sfp := src.offset(fi.field)
// As an optimization, we can avoid the merge function call cost
// if we know for sure that the source will have no effect
// by checking if it is the zero value.
if unsafeAllowed {
if fi.isPointer && sfp.getPointer().isNil() { // Could be slice or string
continue
}
if fi.basicWidth > 0 {
switch {
case fi.basicWidth == 1 && !*sfp.toBool():
continue
case fi.basicWidth == 4 && *sfp.toUint32() == 0:
continue
case fi.basicWidth == 8 && *sfp.toUint64() == 0:
continue
}
}
}
dfp := dst.offset(fi.field)
fi.merge(dfp, sfp)
}
// TODO: Make this faster?
out := dst.asPointerTo(mi.typ).Elem()
in := src.asPointerTo(mi.typ).Elem()
if emIn, err := extendable(in.Addr().Interface()); err == nil {
emOut, _ := extendable(out.Addr().Interface())
mIn, muIn := emIn.extensionsRead()
if mIn != nil {
mOut := emOut.extensionsWrite()
muIn.Lock()
mergeExtension(mOut, mIn)
muIn.Unlock()
}
}
if mi.unrecognized.IsValid() {
if b := *src.offset(mi.unrecognized).toBytes(); len(b) > 0 {
*dst.offset(mi.unrecognized).toBytes() = append([]byte(nil), b...)
}
}
}
func (mi *mergeInfo) computeMergeInfo() {
mi.lock.Lock()
defer mi.lock.Unlock()
if mi.initialized != 0 {
return
}
t := mi.typ
n := t.NumField()
props := GetProperties(t)
for i := 0; i < n; i++ {
f := t.Field(i)
if strings.HasPrefix(f.Name, "XXX_") {
continue
}
mfi := mergeFieldInfo{field: toField(&f)}
tf := f.Type
// As an optimization, we can avoid the merge function call cost
// if we know for sure that the source will have no effect
// by checking if it is the zero value.
if unsafeAllowed {
switch tf.Kind() {
case reflect.Ptr, reflect.Slice, reflect.String:
// As a special case, we assume slices and strings are pointers
// since we know that the first field in the SliceSlice or
// StringHeader is a data pointer.
mfi.isPointer = true
case reflect.Bool:
mfi.basicWidth = 1
case reflect.Int32, reflect.Uint32, reflect.Float32:
mfi.basicWidth = 4
case reflect.Int64, reflect.Uint64, reflect.Float64:
mfi.basicWidth = 8
}
}
// Unwrap tf to get at 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("both pointer and slice for basic type in " + tf.Name())
}
switch tf.Kind() {
case reflect.Int32:
switch {
case isSlice: // E.g., []int32
mfi.merge = func(dst, src pointer) {
// NOTE: toInt32Slice is not defined (see pointer_reflect.go).
/*
sfsp := src.toInt32Slice()
if *sfsp != nil {
dfsp := dst.toInt32Slice()
*dfsp = append(*dfsp, *sfsp...)
if *dfsp == nil {
*dfsp = []int64{}
}
}
*/
sfs := src.getInt32Slice()
if sfs != nil {
dfs := dst.getInt32Slice()
dfs = append(dfs, sfs...)
if dfs == nil {
dfs = []int32{}
}
dst.setInt32Slice(dfs)
}
}
case isPointer: // E.g., *int32
mfi.merge = func(dst, src pointer) {
// NOTE: toInt32Ptr is not defined (see pointer_reflect.go).
/*
sfpp := src.toInt32Ptr()
if *sfpp != nil {
dfpp := dst.toInt32Ptr()
if *dfpp == nil {
*dfpp = Int32(**sfpp)
} else {
**dfpp = **sfpp
}
}
*/
sfp := src.getInt32Ptr()
if sfp != nil {
dfp := dst.getInt32Ptr()
if dfp == nil {
dst.setInt32Ptr(*sfp)
} else {
*dfp = *sfp
}
}
}
default: // E.g., int32
mfi.merge = func(dst, src pointer) {
if v := *src.toInt32(); v != 0 {
*dst.toInt32() = v
}
}
}
case reflect.Int64:
switch {
case isSlice: // E.g., []int64
mfi.merge = func(dst, src pointer) {
sfsp := src.toInt64Slice()
if *sfsp != nil {
dfsp := dst.toInt64Slice()
*dfsp = append(*dfsp, *sfsp...)
if *dfsp == nil {
*dfsp = []int64{}
}
}
}
case isPointer: // E.g., *int64
mfi.merge = func(dst, src pointer) {
sfpp := src.toInt64Ptr()
if *sfpp != nil {
dfpp := dst.toInt64Ptr()
if *dfpp == nil {
*dfpp = Int64(**sfpp)
} else {
**dfpp = **sfpp
}
}
}
default: // E.g., int64
mfi.merge = func(dst, src pointer) {
if v := *src.toInt64(); v != 0 {
*dst.toInt64() = v
}
}
}
case reflect.Uint32:
switch {
case isSlice: // E.g., []uint32
mfi.merge = func(dst, src pointer) {
sfsp := src.toUint32Slice()
if *sfsp != nil {
dfsp := dst.toUint32Slice()
*dfsp = append(*dfsp, *sfsp...)
if *dfsp == nil {
*dfsp = []uint32{}
}
}
}
case isPointer: // E.g., *uint32
mfi.merge = func(dst, src pointer) {
sfpp := src.toUint32Ptr()
if *sfpp != nil {
dfpp := dst.toUint32Ptr()
if *dfpp == nil {
*dfpp = Uint32(**sfpp)
} else {
**dfpp = **sfpp
}
}
}
default: // E.g., uint32
mfi.merge = func(dst, src pointer) {
if v := *src.toUint32(); v != 0 {
*dst.toUint32() = v
}
}
}
case reflect.Uint64:
switch {
case isSlice: // E.g., []uint64
mfi.merge = func(dst, src pointer) {
sfsp := src.toUint64Slice()
if *sfsp != nil {
dfsp := dst.toUint64Slice()
*dfsp = append(*dfsp, *sfsp...)
if *dfsp == nil {
*dfsp = []uint64{}
}
}
}
case isPointer: // E.g., *uint64
mfi.merge = func(dst, src pointer) {
sfpp := src.toUint64Ptr()
if *sfpp != nil {
dfpp := dst.toUint64Ptr()
if *dfpp == nil {
*dfpp = Uint64(**sfpp)
} else {
**dfpp = **sfpp
}
}
}
default: // E.g., uint64
mfi.merge = func(dst, src pointer) {
if v := *src.toUint64(); v != 0 {
*dst.toUint64() = v
}
}
}
case reflect.Float32:
switch {
case isSlice: // E.g., []float32
mfi.merge = func(dst, src pointer) {
sfsp := src.toFloat32Slice()
if *sfsp != nil {
dfsp := dst.toFloat32Slice()
*dfsp = append(*dfsp, *sfsp...)
if *dfsp == nil {
*dfsp = []float32{}
}
}
}
case isPointer: // E.g., *float32
mfi.merge = func(dst, src pointer) {
sfpp := src.toFloat32Ptr()
if *sfpp != nil {
dfpp := dst.toFloat32Ptr()
if *dfpp == nil {
*dfpp = Float32(**sfpp)
} else {
**dfpp = **sfpp
}
}
}
default: // E.g., float32
mfi.merge = func(dst, src pointer) {
if v := *src.toFloat32(); v != 0 {
*dst.toFloat32() = v
}
}
}
case reflect.Float64:
switch {
case isSlice: // E.g., []float64
mfi.merge = func(dst, src pointer) {
sfsp := src.toFloat64Slice()
if *sfsp != nil {
dfsp := dst.toFloat64Slice()
*dfsp = append(*dfsp, *sfsp...)
if *dfsp == nil {
*dfsp = []float64{}
}
}
}
case isPointer: // E.g., *float64
mfi.merge = func(dst, src pointer) {
sfpp := src.toFloat64Ptr()
if *sfpp != nil {
dfpp := dst.toFloat64Ptr()
if *dfpp == nil {
*dfpp = Float64(**sfpp)
} else {
**dfpp = **sfpp
}
}
}
default: // E.g., float64
mfi.merge = func(dst, src pointer) {
if v := *src.toFloat64(); v != 0 {
*dst.toFloat64() = v
}
}
}
case reflect.Bool:
switch {
case isSlice: // E.g., []bool
mfi.merge = func(dst, src pointer) {
sfsp := src.toBoolSlice()
if *sfsp != nil {
dfsp := dst.toBoolSlice()
*dfsp = append(*dfsp, *sfsp...)
if *dfsp == nil {
*dfsp = []bool{}
}
}
}
case isPointer: // E.g., *bool
mfi.merge = func(dst, src pointer) {
sfpp := src.toBoolPtr()
if *sfpp != nil {
dfpp := dst.toBoolPtr()
if *dfpp == nil {
*dfpp = Bool(**sfpp)
} else {
**dfpp = **sfpp
}
}
}
default: // E.g., bool
mfi.merge = func(dst, src pointer) {
if v := *src.toBool(); v {
*dst.toBool() = v
}
}
}
case reflect.String:
switch {
case isSlice: // E.g., []string
mfi.merge = func(dst, src pointer) {
sfsp := src.toStringSlice()
if *sfsp != nil {
dfsp := dst.toStringSlice()
*dfsp = append(*dfsp, *sfsp...)
if *dfsp == nil {
*dfsp = []string{}
}
}
}
case isPointer: // E.g., *string
mfi.merge = func(dst, src pointer) {
sfpp := src.toStringPtr()
if *sfpp != nil {
dfpp := dst.toStringPtr()
if *dfpp == nil {
*dfpp = String(**sfpp)
} else {
**dfpp = **sfpp
}
}
}
default: // E.g., string
mfi.merge = func(dst, src pointer) {
if v := *src.toString(); v != "" {
*dst.toString() = v
}
}
}
case reflect.Slice:
isProto3 := props.Prop[i].proto3
switch {
case isPointer:
panic("bad pointer in byte slice case in " + tf.Name())
case tf.Elem().Kind() != reflect.Uint8:
panic("bad element kind in byte slice case in " + tf.Name())
case isSlice: // E.g., [][]byte
mfi.merge = func(dst, src pointer) {
sbsp := src.toBytesSlice()
if *sbsp != nil {
dbsp := dst.toBytesSlice()
for _, sb := range *sbsp {
if sb == nil {
*dbsp = append(*dbsp, nil)
} else {
*dbsp = append(*dbsp, append([]byte{}, sb...))
}
}
if *dbsp == nil {
*dbsp = [][]byte{}
}
}
}
default: // E.g., []byte
mfi.merge = func(dst, src pointer) {
sbp := src.toBytes()
if *sbp != nil {
dbp := dst.toBytes()
if !isProto3 || len(*sbp) > 0 {
*dbp = append([]byte{}, *sbp...)
}
}
}
}
case reflect.Struct:
switch {
case !isPointer:
panic(fmt.Sprintf("message field %s without pointer", tf))
case isSlice: // E.g., []*pb.T
mi := getMergeInfo(tf)
mfi.merge = func(dst, src pointer) {
sps := src.getPointerSlice()
if sps != nil {
dps := dst.getPointerSlice()
for _, sp := range sps {
var dp pointer
if !sp.isNil() {
dp = valToPointer(reflect.New(tf))
mi.merge(dp, sp)
}
dps = append(dps, dp)
}
if dps == nil {
dps = []pointer{}
}
dst.setPointerSlice(dps)
}
}
default: // E.g., *pb.T
mi := getMergeInfo(tf)
mfi.merge = func(dst, src pointer) {
sp := src.getPointer()
if !sp.isNil() {
dp := dst.getPointer()
if dp.isNil() {
dp = valToPointer(reflect.New(tf))
dst.setPointer(dp)
}
mi.merge(dp, sp)
}
}
}
case reflect.Map:
switch {
case isPointer || isSlice:
panic("bad pointer or slice in map case in " + tf.Name())
default: // E.g., map[K]V
mfi.merge = func(dst, src pointer) {
sm := src.asPointerTo(tf).Elem()
if sm.Len() == 0 {
return
}
dm := dst.asPointerTo(tf).Elem()
if dm.IsNil() {
dm.Set(reflect.MakeMap(tf))
}
switch tf.Elem().Kind() {
case reflect.Ptr: // Proto struct (e.g., *T)
for _, key := range sm.MapKeys() {
val := sm.MapIndex(key)
val = reflect.ValueOf(Clone(val.Interface().(Message)))
dm.SetMapIndex(key, val)
}
case reflect.Slice: // E.g. Bytes type (e.g., []byte)
for _, key := range sm.MapKeys() {
val := sm.MapIndex(key)
val = reflect.ValueOf(append([]byte{}, val.Bytes()...))
dm.SetMapIndex(key, val)
}
default: // Basic type (e.g., string)
for _, key := range sm.MapKeys() {
val := sm.MapIndex(key)
dm.SetMapIndex(key, val)
}
}
}
}
case reflect.Interface:
// Must be oneof field.
switch {
case isPointer || isSlice:
panic("bad pointer or slice in interface case in " + tf.Name())
default: // E.g., interface{}
// TODO: Make this faster?
mfi.merge = func(dst, src pointer) {
su := src.asPointerTo(tf).Elem()
if !su.IsNil() {
du := dst.asPointerTo(tf).Elem()
typ := su.Elem().Type()
if du.IsNil() || du.Elem().Type() != typ {
du.Set(reflect.New(typ.Elem())) // Initialize interface if empty
}
sv := su.Elem().Elem().Field(0)
if sv.Kind() == reflect.Ptr && sv.IsNil() {
return
}
dv := du.Elem().Elem().Field(0)
if dv.Kind() == reflect.Ptr && dv.IsNil() {
dv.Set(reflect.New(sv.Type().Elem())) // Initialize proto message if empty
}
switch sv.Type().Kind() {
case reflect.Ptr: // Proto struct (e.g., *T)
Merge(dv.Interface().(Message), sv.Interface().(Message))
case reflect.Slice: // E.g. Bytes type (e.g., []byte)
dv.Set(reflect.ValueOf(append([]byte{}, sv.Bytes()...)))
default: // Basic type (e.g., string)
dv.Set(sv)
}
}
}
}
default:
panic(fmt.Sprintf("merger not found for type:%s", tf))
}
mi.fields = append(mi.fields, mfi)
}
mi.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")
}
mi.unrecognized = toField(&f)
}
atomic.StoreInt32(&mi.initialized, 1)
}