github.com/matm/etcd@v0.3.1-0.20140328024009-5b4a473f1453/third_party/code.google.com/p/gogoprotobuf/proto/skip_gogo.go (about) 1 // Copyright (c) 2013, Vastech SA (PTY) LTD. All rights reserved. 2 // http://code.google.com/p/gogoprotobuf/gogoproto 3 // 4 // Redistribution and use in source and binary forms, with or without 5 // modification, are permitted provided that the following conditions are 6 // met: 7 // 8 // * Redistributions of source code must retain the above copyright 9 // notice, this list of conditions and the following disclaimer. 10 // * Redistributions in binary form must reproduce the above 11 // copyright notice, this list of conditions and the following disclaimer 12 // in the documentation and/or other materials provided with the 13 // distribution. 14 // 15 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 18 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 19 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 20 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 21 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 25 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 27 package proto 28 29 import ( 30 "io" 31 ) 32 33 func Skip(data []byte) (n int, err error) { 34 l := len(data) 35 index := 0 36 for index < l { 37 var wire uint64 38 for shift := uint(0); ; shift += 7 { 39 if index >= l { 40 return 0, io.ErrUnexpectedEOF 41 } 42 b := data[index] 43 index++ 44 wire |= (uint64(b) & 0x7F) << shift 45 if b < 0x80 { 46 break 47 } 48 } 49 wireType := int(wire & 0x7) 50 switch wireType { 51 case 0: 52 for { 53 if index >= l { 54 return 0, io.ErrUnexpectedEOF 55 } 56 index++ 57 if data[index-1] < 0x80 { 58 break 59 } 60 } 61 return index, nil 62 case 1: 63 index += 8 64 return index, nil 65 case 2: 66 var length int 67 for shift := uint(0); ; shift += 7 { 68 if index >= l { 69 return 0, io.ErrUnexpectedEOF 70 } 71 b := data[index] 72 index++ 73 length |= (int(b) & 0x7F) << shift 74 if b < 0x80 { 75 break 76 } 77 } 78 index += length 79 return index, nil 80 case 3: 81 for { 82 var wire uint64 83 var start int = index 84 for shift := uint(0); ; shift += 7 { 85 if index >= l { 86 return 0, io.ErrUnexpectedEOF 87 } 88 b := data[index] 89 index++ 90 wire |= (uint64(b) & 0x7F) << shift 91 if b < 0x80 { 92 break 93 } 94 } 95 wireType := int(wire & 0x7) 96 if wireType == 4 { 97 break 98 } 99 next, err := Skip(data[start:]) 100 if err != nil { 101 return 0, err 102 } 103 index = start + next 104 } 105 return index, nil 106 case 4: 107 return index, nil 108 case 5: 109 index += 4 110 return index, nil 111 default: 112 return 0, ErrWrongType 113 } 114 } 115 panic("unreachable") 116 }