diff options
Diffstat (limited to 'vendor/google.golang.org/protobuf/internal/impl/legacy_export.go')
-rw-r--r-- | vendor/google.golang.org/protobuf/internal/impl/legacy_export.go | 92 |
1 files changed, 92 insertions, 0 deletions
diff --git a/vendor/google.golang.org/protobuf/internal/impl/legacy_export.go b/vendor/google.golang.org/protobuf/internal/impl/legacy_export.go new file mode 100644 index 000000000..c3d741c2f --- /dev/null +++ b/vendor/google.golang.org/protobuf/internal/impl/legacy_export.go @@ -0,0 +1,92 @@ +// Copyright 2019 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package impl + +import ( + "encoding/binary" + "encoding/json" + "hash/crc32" + "math" + "reflect" + + "google.golang.org/protobuf/internal/errors" + pref "google.golang.org/protobuf/reflect/protoreflect" + piface "google.golang.org/protobuf/runtime/protoiface" +) + +// These functions exist to support exported APIs in generated protobufs. +// While these are deprecated, they cannot be removed for compatibility reasons. + +// LegacyEnumName returns the name of enums used in legacy code. +func (Export) LegacyEnumName(ed pref.EnumDescriptor) string { + return legacyEnumName(ed) +} + +// LegacyMessageTypeOf returns the protoreflect.MessageType for m, +// with name used as the message name if necessary. +func (Export) LegacyMessageTypeOf(m piface.MessageV1, name pref.FullName) pref.MessageType { + if mv := (Export{}).protoMessageV2Of(m); mv != nil { + return mv.ProtoReflect().Type() + } + return legacyLoadMessageInfo(reflect.TypeOf(m), name) +} + +// UnmarshalJSONEnum unmarshals an enum from a JSON-encoded input. +// The input can either be a string representing the enum value by name, +// or a number representing the enum number itself. +func (Export) UnmarshalJSONEnum(ed pref.EnumDescriptor, b []byte) (pref.EnumNumber, error) { + if b[0] == '"' { + var name pref.Name + if err := json.Unmarshal(b, &name); err != nil { + return 0, errors.New("invalid input for enum %v: %s", ed.FullName(), b) + } + ev := ed.Values().ByName(name) + if ev == nil { + return 0, errors.New("invalid value for enum %v: %s", ed.FullName(), name) + } + return ev.Number(), nil + } else { + var num pref.EnumNumber + if err := json.Unmarshal(b, &num); err != nil { + return 0, errors.New("invalid input for enum %v: %s", ed.FullName(), b) + } + return num, nil + } +} + +// CompressGZIP compresses the input as a GZIP-encoded file. +// The current implementation does no compression. +func (Export) CompressGZIP(in []byte) (out []byte) { + // RFC 1952, section 2.3.1. + var gzipHeader = [10]byte{0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff} + + // RFC 1951, section 3.2.4. + var blockHeader [5]byte + const maxBlockSize = math.MaxUint16 + numBlocks := 1 + len(in)/maxBlockSize + + // RFC 1952, section 2.3.1. + var gzipFooter [8]byte + binary.LittleEndian.PutUint32(gzipFooter[0:4], crc32.ChecksumIEEE(in)) + binary.LittleEndian.PutUint32(gzipFooter[4:8], uint32(len(in))) + + // Encode the input without compression using raw DEFLATE blocks. + out = make([]byte, 0, len(gzipHeader)+len(blockHeader)*numBlocks+len(in)+len(gzipFooter)) + out = append(out, gzipHeader[:]...) + for blockHeader[0] == 0 { + blockSize := maxBlockSize + if blockSize > len(in) { + blockHeader[0] = 0x01 // final bit per RFC 1951, section 3.2.3. + blockSize = len(in) + } + binary.LittleEndian.PutUint16(blockHeader[1:3], uint16(blockSize)^0x0000) + binary.LittleEndian.PutUint16(blockHeader[3:5], uint16(blockSize)^0xffff) + out = append(out, blockHeader[:]...) + out = append(out, in[:blockSize]...) + in = in[blockSize:] + } + out = append(out, gzipFooter[:]...) + return out +} |