301 lines
8.7 KiB
Go
301 lines
8.7 KiB
Go
// Go support for Protocol Buffers - Google's data interchange format
|
|
//
|
|
// Copyright 2011 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.
|
|
|
|
// Protocol buffer comparison.
|
|
|
|
package proto
|
|
|
|
import (
|
|
"bytes"
|
|
"log"
|
|
"reflect"
|
|
"strings"
|
|
)
|
|
|
|
/*
|
|
Equal returns true iff protocol buffers a and b are equal.
|
|
The arguments must both be pointers to protocol buffer structs.
|
|
|
|
Equality is defined in this way:
|
|
- Two messages are equal iff they are the same type,
|
|
corresponding fields are equal, unknown field sets
|
|
are equal, and extensions sets are equal.
|
|
- Two set scalar fields are equal iff their values are equal.
|
|
If the fields are of a floating-point type, remember that
|
|
NaN != x for all x, including NaN. If the message is defined
|
|
in a proto3 .proto file, fields are not "set"; specifically,
|
|
zero length proto3 "bytes" fields are equal (nil == {}).
|
|
- Two repeated fields are equal iff their lengths are the same,
|
|
and their corresponding elements are equal. Note a "bytes" field,
|
|
although represented by []byte, is not a repeated field and the
|
|
rule for the scalar fields described above applies.
|
|
- Two unset fields are equal.
|
|
- Two unknown field sets are equal if their current
|
|
encoded state is equal.
|
|
- Two extension sets are equal iff they have corresponding
|
|
elements that are pairwise equal.
|
|
- Two map fields are equal iff their lengths are the same,
|
|
and they contain the same set of elements. Zero-length map
|
|
fields are equal.
|
|
- Every other combination of things are not equal.
|
|
|
|
The return value is undefined if a and b are not protocol buffers.
|
|
*/
|
|
func Equal(a, b Message) bool {
|
|
if a == nil || b == nil {
|
|
return a == b
|
|
}
|
|
v1, v2 := reflect.ValueOf(a), reflect.ValueOf(b)
|
|
if v1.Type() != v2.Type() {
|
|
return false
|
|
}
|
|
if v1.Kind() == reflect.Ptr {
|
|
if v1.IsNil() {
|
|
return v2.IsNil()
|
|
}
|
|
if v2.IsNil() {
|
|
return false
|
|
}
|
|
v1, v2 = v1.Elem(), v2.Elem()
|
|
}
|
|
if v1.Kind() != reflect.Struct {
|
|
return false
|
|
}
|
|
return equalStruct(v1, v2)
|
|
}
|
|
|
|
// v1 and v2 are known to have the same type.
|
|
func equalStruct(v1, v2 reflect.Value) bool {
|
|
sprop := GetProperties(v1.Type())
|
|
for i := 0; i < v1.NumField(); i++ {
|
|
f := v1.Type().Field(i)
|
|
if strings.HasPrefix(f.Name, "XXX_") {
|
|
continue
|
|
}
|
|
f1, f2 := v1.Field(i), v2.Field(i)
|
|
if f.Type.Kind() == reflect.Ptr {
|
|
if n1, n2 := f1.IsNil(), f2.IsNil(); n1 && n2 {
|
|
// both unset
|
|
continue
|
|
} else if n1 != n2 {
|
|
// set/unset mismatch
|
|
return false
|
|
}
|
|
f1, f2 = f1.Elem(), f2.Elem()
|
|
}
|
|
if !equalAny(f1, f2, sprop.Prop[i]) {
|
|
return false
|
|
}
|
|
}
|
|
|
|
if em1 := v1.FieldByName("XXX_InternalExtensions"); em1.IsValid() {
|
|
em2 := v2.FieldByName("XXX_InternalExtensions")
|
|
if !equalExtensions(v1.Type(), em1.Interface().(XXX_InternalExtensions), em2.Interface().(XXX_InternalExtensions)) {
|
|
return false
|
|
}
|
|
}
|
|
|
|
if em1 := v1.FieldByName("XXX_extensions"); em1.IsValid() {
|
|
em2 := v2.FieldByName("XXX_extensions")
|
|
if !equalExtMap(v1.Type(), em1.Interface().(map[int32]Extension), em2.Interface().(map[int32]Extension)) {
|
|
return false
|
|
}
|
|
}
|
|
|
|
uf := v1.FieldByName("XXX_unrecognized")
|
|
if !uf.IsValid() {
|
|
return true
|
|
}
|
|
|
|
u1 := uf.Bytes()
|
|
u2 := v2.FieldByName("XXX_unrecognized").Bytes()
|
|
return bytes.Equal(u1, u2)
|
|
}
|
|
|
|
// v1 and v2 are known to have the same type.
|
|
// prop may be nil.
|
|
func equalAny(v1, v2 reflect.Value, prop *Properties) bool {
|
|
if v1.Type() == protoMessageType {
|
|
m1, _ := v1.Interface().(Message)
|
|
m2, _ := v2.Interface().(Message)
|
|
return Equal(m1, m2)
|
|
}
|
|
switch v1.Kind() {
|
|
case reflect.Bool:
|
|
return v1.Bool() == v2.Bool()
|
|
case reflect.Float32, reflect.Float64:
|
|
return v1.Float() == v2.Float()
|
|
case reflect.Int32, reflect.Int64:
|
|
return v1.Int() == v2.Int()
|
|
case reflect.Interface:
|
|
// Probably a oneof field; compare the inner values.
|
|
n1, n2 := v1.IsNil(), v2.IsNil()
|
|
if n1 || n2 {
|
|
return n1 == n2
|
|
}
|
|
e1, e2 := v1.Elem(), v2.Elem()
|
|
if e1.Type() != e2.Type() {
|
|
return false
|
|
}
|
|
return equalAny(e1, e2, nil)
|
|
case reflect.Map:
|
|
if v1.Len() != v2.Len() {
|
|
return false
|
|
}
|
|
for _, key := range v1.MapKeys() {
|
|
val2 := v2.MapIndex(key)
|
|
if !val2.IsValid() {
|
|
// This key was not found in the second map.
|
|
return false
|
|
}
|
|
if !equalAny(v1.MapIndex(key), val2, nil) {
|
|
return false
|
|
}
|
|
}
|
|
return true
|
|
case reflect.Ptr:
|
|
// Maps may have nil values in them, so check for nil.
|
|
if v1.IsNil() && v2.IsNil() {
|
|
return true
|
|
}
|
|
if v1.IsNil() != v2.IsNil() {
|
|
return false
|
|
}
|
|
return equalAny(v1.Elem(), v2.Elem(), prop)
|
|
case reflect.Slice:
|
|
if v1.Type().Elem().Kind() == reflect.Uint8 {
|
|
// short circuit: []byte
|
|
|
|
// Edge case: if this is in a proto3 message, a zero length
|
|
// bytes field is considered the zero value.
|
|
if prop != nil && prop.proto3 && v1.Len() == 0 && v2.Len() == 0 {
|
|
return true
|
|
}
|
|
if v1.IsNil() != v2.IsNil() {
|
|
return false
|
|
}
|
|
return bytes.Equal(v1.Interface().([]byte), v2.Interface().([]byte))
|
|
}
|
|
|
|
if v1.Len() != v2.Len() {
|
|
return false
|
|
}
|
|
for i := 0; i < v1.Len(); i++ {
|
|
if !equalAny(v1.Index(i), v2.Index(i), prop) {
|
|
return false
|
|
}
|
|
}
|
|
return true
|
|
case reflect.String:
|
|
return v1.Interface().(string) == v2.Interface().(string)
|
|
case reflect.Struct:
|
|
return equalStruct(v1, v2)
|
|
case reflect.Uint32, reflect.Uint64:
|
|
return v1.Uint() == v2.Uint()
|
|
}
|
|
|
|
// unknown type, so not a protocol buffer
|
|
log.Printf("proto: don't know how to compare %v", v1)
|
|
return false
|
|
}
|
|
|
|
// base is the struct type that the extensions are based on.
|
|
// x1 and x2 are InternalExtensions.
|
|
func equalExtensions(base reflect.Type, x1, x2 XXX_InternalExtensions) bool {
|
|
em1, _ := x1.extensionsRead()
|
|
em2, _ := x2.extensionsRead()
|
|
return equalExtMap(base, em1, em2)
|
|
}
|
|
|
|
func equalExtMap(base reflect.Type, em1, em2 map[int32]Extension) bool {
|
|
if len(em1) != len(em2) {
|
|
return false
|
|
}
|
|
|
|
for extNum, e1 := range em1 {
|
|
e2, ok := em2[extNum]
|
|
if !ok {
|
|
return false
|
|
}
|
|
|
|
m1, m2 := e1.value, e2.value
|
|
|
|
if m1 == nil && m2 == nil {
|
|
// Both have only encoded form.
|
|
if bytes.Equal(e1.enc, e2.enc) {
|
|
continue
|
|
}
|
|
// The bytes are different, but the extensions might still be
|
|
// equal. We need to decode them to compare.
|
|
}
|
|
|
|
if m1 != nil && m2 != nil {
|
|
// Both are unencoded.
|
|
if !equalAny(reflect.ValueOf(m1), reflect.ValueOf(m2), nil) {
|
|
return false
|
|
}
|
|
continue
|
|
}
|
|
|
|
// At least one is encoded. To do a semantically correct comparison
|
|
// we need to unmarshal them first.
|
|
var desc *ExtensionDesc
|
|
if m := extensionMaps[base]; m != nil {
|
|
desc = m[extNum]
|
|
}
|
|
if desc == nil {
|
|
// If both have only encoded form and the bytes are the same,
|
|
// it is handled above. We get here when the bytes are different.
|
|
// We don't know how to decode it, so just compare them as byte
|
|
// slices.
|
|
log.Printf("proto: don't know how to compare extension %d of %v", extNum, base)
|
|
return false
|
|
}
|
|
var err error
|
|
if m1 == nil {
|
|
m1, err = decodeExtension(e1.enc, desc)
|
|
}
|
|
if m2 == nil && err == nil {
|
|
m2, err = decodeExtension(e2.enc, desc)
|
|
}
|
|
if err != nil {
|
|
// The encoded form is invalid.
|
|
log.Printf("proto: badly encoded extension %d of %v: %v", extNum, base, err)
|
|
return false
|
|
}
|
|
if !equalAny(reflect.ValueOf(m1), reflect.ValueOf(m2), nil) {
|
|
return false
|
|
}
|
|
}
|
|
|
|
return true
|
|
}
|