--- /dev/null
+// 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
+}
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