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Diffstat (limited to 'vendor/github.com/golang/protobuf/proto/equal.go')
-rw-r--r-- | vendor/github.com/golang/protobuf/proto/equal.go | 300 |
1 files changed, 300 insertions, 0 deletions
diff --git a/vendor/github.com/golang/protobuf/proto/equal.go b/vendor/github.com/golang/protobuf/proto/equal.go new file mode 100644 index 00000000..2ed1cf59 --- /dev/null +++ b/vendor/github.com/golang/protobuf/proto/equal.go @@ -0,0 +1,300 @@ +// 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 + } + b1, ok := f1.Interface().(raw) + if ok { + b2 := f2.Interface().(raw) + // RawMessage + if !bytes.Equal(b1.Bytes(), b2.Bytes()) { + return false + } + continue + } + 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() + if !bytes.Equal(u1, u2) { + return false + } + + return true +} + +// 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 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 { + log.Printf("proto: don't know how to compare extension %d of %v", extNum, base) + continue + } + 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 +} |