1 // Protocol Buffers - Google's data interchange format 2 // Copyright 2008 Google Inc. All rights reserved. 3 // http://code.google.com/p/protobuf/ 4 // 5 // Redistribution and use in source and binary forms, with or without 6 // modification, are permitted provided that the following conditions are 7 // met: 8 // 9 // * Redistributions of source code must retain the above copyright 10 // notice, this list of conditions and the following disclaimer. 11 // * Redistributions in binary form must reproduce the above 12 // copyright notice, this list of conditions and the following disclaimer 13 // in the documentation and/or other materials provided with the 14 // distribution. 15 // * Neither the name of Google Inc. nor the names of its 16 // contributors may be used to endorse or promote products derived from 17 // this software without specific prior written permission. 18 // 19 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 20 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 21 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 22 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 23 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 24 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 25 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 26 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 27 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 28 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 29 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 30 31 // Authors: wink (at) google.com (Wink Saville), 32 // kenton (at) google.com (Kenton Varda) 33 // Based on original Protocol Buffers design by 34 // Sanjay Ghemawat, Jeff Dean, and others. 35 36 #include <google/protobuf/message_lite.h> 37 #include <string> 38 #include <google/protobuf/stubs/common.h> 39 #include <google/protobuf/io/coded_stream.h> 40 #include <google/protobuf/io/zero_copy_stream_impl.h> 41 #include <google/protobuf/stubs/stl_util-inl.h> 42 43 namespace google { 44 namespace protobuf { 45 46 MessageLite::~MessageLite() {} 47 48 string MessageLite::InitializationErrorString() const { 49 return "(cannot determine missing fields for lite message)"; 50 } 51 52 namespace { 53 54 // When serializing, we first compute the byte size, then serialize the message. 55 // If serialization produces a different number of bytes than expected, we 56 // call this function, which crashes. The problem could be due to a bug in the 57 // protobuf implementation but is more likely caused by concurrent modification 58 // of the message. This function attempts to distinguish between the two and 59 // provide a useful error message. 60 void ByteSizeConsistencyError(int byte_size_before_serialization, 61 int byte_size_after_serialization, 62 int bytes_produced_by_serialization) { 63 GOOGLE_CHECK_EQ(byte_size_before_serialization, byte_size_after_serialization) 64 << "Protocol message was modified concurrently during serialization."; 65 GOOGLE_CHECK_EQ(bytes_produced_by_serialization, byte_size_before_serialization) 66 << "Byte size calculation and serialization were inconsistent. This " 67 "may indicate a bug in protocol buffers or it may be caused by " 68 "concurrent modification of the message."; 69 GOOGLE_LOG(FATAL) << "This shouldn't be called if all the sizes are equal."; 70 } 71 72 string InitializationErrorMessage(const char* action, 73 const MessageLite& message) { 74 // Note: We want to avoid depending on strutil in the lite library, otherwise 75 // we'd use: 76 // 77 // return strings::Substitute( 78 // "Can't $0 message of type \"$1\" because it is missing required " 79 // "fields: $2", 80 // action, message.GetTypeName(), 81 // message.InitializationErrorString()); 82 83 string result; 84 result += "Can't "; 85 result += action; 86 result += " message of type \""; 87 result += message.GetTypeName(); 88 result += "\" because it is missing required fields: "; 89 result += message.InitializationErrorString(); 90 return result; 91 } 92 93 // Several of the Parse methods below just do one thing and then call another 94 // method. In a naive implementation, we might have ParseFromString() call 95 // ParseFromArray() which would call ParseFromZeroCopyStream() which would call 96 // ParseFromCodedStream() which would call MergeFromCodedStream() which would 97 // call MergePartialFromCodedStream(). However, when parsing very small 98 // messages, every function call introduces significant overhead. To avoid 99 // this without reproducing code, we use these forced-inline helpers. 100 // 101 // Note: GCC only allows GOOGLE_ATTRIBUTE_ALWAYS_INLINE on declarations, not 102 // definitions. 103 inline bool InlineMergeFromCodedStream(io::CodedInputStream* input, 104 MessageLite* message) 105 GOOGLE_ATTRIBUTE_ALWAYS_INLINE; 106 inline bool InlineParseFromCodedStream(io::CodedInputStream* input, 107 MessageLite* message) 108 GOOGLE_ATTRIBUTE_ALWAYS_INLINE; 109 inline bool InlineParsePartialFromCodedStream(io::CodedInputStream* input, 110 MessageLite* message) 111 GOOGLE_ATTRIBUTE_ALWAYS_INLINE; 112 inline bool InlineParseFromArray(const void* data, int size, 113 MessageLite* message) 114 GOOGLE_ATTRIBUTE_ALWAYS_INLINE; 115 inline bool InlineParsePartialFromArray(const void* data, int size, 116 MessageLite* message) 117 GOOGLE_ATTRIBUTE_ALWAYS_INLINE; 118 119 bool InlineMergeFromCodedStream(io::CodedInputStream* input, 120 MessageLite* message) { 121 if (!message->MergePartialFromCodedStream(input)) return false; 122 if (!message->IsInitialized()) { 123 GOOGLE_LOG(ERROR) << InitializationErrorMessage("parse", *message); 124 return false; 125 } 126 return true; 127 } 128 129 bool InlineParseFromCodedStream(io::CodedInputStream* input, 130 MessageLite* message) { 131 message->Clear(); 132 return InlineMergeFromCodedStream(input, message); 133 } 134 135 bool InlineParsePartialFromCodedStream(io::CodedInputStream* input, 136 MessageLite* message) { 137 message->Clear(); 138 return message->MergePartialFromCodedStream(input); 139 } 140 141 bool InlineParseFromArray(const void* data, int size, MessageLite* message) { 142 io::CodedInputStream input(reinterpret_cast<const uint8*>(data), size); 143 return InlineParseFromCodedStream(&input, message) && 144 input.ConsumedEntireMessage(); 145 } 146 147 bool InlineParsePartialFromArray(const void* data, int size, 148 MessageLite* message) { 149 io::CodedInputStream input(reinterpret_cast<const uint8*>(data), size); 150 return InlineParsePartialFromCodedStream(&input, message) && 151 input.ConsumedEntireMessage(); 152 } 153 154 } // namespace 155 156 bool MessageLite::MergeFromCodedStream(io::CodedInputStream* input) { 157 return InlineMergeFromCodedStream(input, this); 158 } 159 160 bool MessageLite::ParseFromCodedStream(io::CodedInputStream* input) { 161 return InlineParseFromCodedStream(input, this); 162 } 163 164 bool MessageLite::ParsePartialFromCodedStream(io::CodedInputStream* input) { 165 return InlineParsePartialFromCodedStream(input, this); 166 } 167 168 bool MessageLite::ParseFromZeroCopyStream(io::ZeroCopyInputStream* input) { 169 io::CodedInputStream decoder(input); 170 return ParseFromCodedStream(&decoder) && decoder.ConsumedEntireMessage(); 171 } 172 173 bool MessageLite::ParsePartialFromZeroCopyStream( 174 io::ZeroCopyInputStream* input) { 175 io::CodedInputStream decoder(input); 176 return ParsePartialFromCodedStream(&decoder) && 177 decoder.ConsumedEntireMessage(); 178 } 179 180 bool MessageLite::ParseFromBoundedZeroCopyStream( 181 io::ZeroCopyInputStream* input, int size) { 182 io::CodedInputStream decoder(input); 183 decoder.PushLimit(size); 184 return ParseFromCodedStream(&decoder) && 185 decoder.ConsumedEntireMessage() && 186 decoder.BytesUntilLimit() == 0; 187 } 188 189 bool MessageLite::ParsePartialFromBoundedZeroCopyStream( 190 io::ZeroCopyInputStream* input, int size) { 191 io::CodedInputStream decoder(input); 192 decoder.PushLimit(size); 193 return ParsePartialFromCodedStream(&decoder) && 194 decoder.ConsumedEntireMessage() && 195 decoder.BytesUntilLimit() == 0; 196 } 197 198 bool MessageLite::ParseFromString(const string& data) { 199 return InlineParseFromArray(data.data(), data.size(), this); 200 } 201 202 bool MessageLite::ParsePartialFromString(const string& data) { 203 return InlineParsePartialFromArray(data.data(), data.size(), this); 204 } 205 206 bool MessageLite::ParseFromArray(const void* data, int size) { 207 return InlineParseFromArray(data, size, this); 208 } 209 210 bool MessageLite::ParsePartialFromArray(const void* data, int size) { 211 return InlineParsePartialFromArray(data, size, this); 212 } 213 214 215 // =================================================================== 216 217 uint8* MessageLite::SerializeWithCachedSizesToArray(uint8* target) const { 218 // We only optimize this when using optimize_for = SPEED. In other cases 219 // we just use the CodedOutputStream path. 220 int size = GetCachedSize(); 221 io::ArrayOutputStream out(target, size); 222 io::CodedOutputStream coded_out(&out); 223 SerializeWithCachedSizes(&coded_out); 224 GOOGLE_CHECK(!coded_out.HadError()); 225 return target + size; 226 } 227 228 bool MessageLite::SerializeToCodedStream(io::CodedOutputStream* output) const { 229 GOOGLE_DCHECK(IsInitialized()) << InitializationErrorMessage("serialize", *this); 230 return SerializePartialToCodedStream(output); 231 } 232 233 bool MessageLite::SerializePartialToCodedStream( 234 io::CodedOutputStream* output) const { 235 const int size = ByteSize(); // Force size to be cached. 236 uint8* buffer = output->GetDirectBufferForNBytesAndAdvance(size); 237 if (buffer != NULL) { 238 uint8* end = SerializeWithCachedSizesToArray(buffer); 239 if (end - buffer != size) { 240 ByteSizeConsistencyError(size, ByteSize(), end - buffer); 241 } 242 return true; 243 } else { 244 int original_byte_count = output->ByteCount(); 245 SerializeWithCachedSizes(output); 246 if (output->HadError()) { 247 return false; 248 } 249 int final_byte_count = output->ByteCount(); 250 251 if (final_byte_count - original_byte_count != size) { 252 ByteSizeConsistencyError(size, ByteSize(), 253 final_byte_count - original_byte_count); 254 } 255 256 return true; 257 } 258 } 259 260 bool MessageLite::SerializeToZeroCopyStream( 261 io::ZeroCopyOutputStream* output) const { 262 io::CodedOutputStream encoder(output); 263 return SerializeToCodedStream(&encoder); 264 } 265 266 bool MessageLite::SerializePartialToZeroCopyStream( 267 io::ZeroCopyOutputStream* output) const { 268 io::CodedOutputStream encoder(output); 269 return SerializePartialToCodedStream(&encoder); 270 } 271 272 bool MessageLite::AppendToString(string* output) const { 273 GOOGLE_DCHECK(IsInitialized()) << InitializationErrorMessage("serialize", *this); 274 return AppendPartialToString(output); 275 } 276 277 bool MessageLite::AppendPartialToString(string* output) const { 278 int old_size = output->size(); 279 int byte_size = ByteSize(); 280 STLStringResizeUninitialized(output, old_size + byte_size); 281 uint8* start = reinterpret_cast<uint8*>(string_as_array(output) + old_size); 282 uint8* end = SerializeWithCachedSizesToArray(start); 283 if (end - start != byte_size) { 284 ByteSizeConsistencyError(byte_size, ByteSize(), end - start); 285 } 286 return true; 287 } 288 289 bool MessageLite::SerializeToString(string* output) const { 290 output->clear(); 291 return AppendToString(output); 292 } 293 294 bool MessageLite::SerializePartialToString(string* output) const { 295 output->clear(); 296 return AppendPartialToString(output); 297 } 298 299 bool MessageLite::SerializeToArray(void* data, int size) const { 300 GOOGLE_DCHECK(IsInitialized()) << InitializationErrorMessage("serialize", *this); 301 return SerializePartialToArray(data, size); 302 } 303 304 bool MessageLite::SerializePartialToArray(void* data, int size) const { 305 int byte_size = ByteSize(); 306 if (size < byte_size) return false; 307 uint8* start = reinterpret_cast<uint8*>(data); 308 uint8* end = SerializeWithCachedSizesToArray(start); 309 if (end - start != byte_size) { 310 ByteSizeConsistencyError(byte_size, ByteSize(), end - start); 311 } 312 return true; 313 } 314 315 string MessageLite::SerializeAsString() const { 316 // If the compiler implements the (Named) Return Value Optimization, 317 // the local variable 'result' will not actually reside on the stack 318 // of this function, but will be overlaid with the object that the 319 // caller supplied for the return value to be constructed in. 320 string output; 321 if (!AppendToString(&output)) 322 output.clear(); 323 return output; 324 } 325 326 string MessageLite::SerializePartialAsString() const { 327 string output; 328 if (!AppendPartialToString(&output)) 329 output.clear(); 330 return output; 331 } 332 333 } // namespace protobuf 334 } // namespace google 335