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@google.com (Wink Saville),
32 // kenton@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
~MessageLite()46 MessageLite::~MessageLite() {}
47
InitializationErrorString() const48 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.
ByteSizeConsistencyError(int byte_size_before_serialization,int byte_size_after_serialization,int bytes_produced_by_serialization)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
InitializationErrorMessage(const char * action,const MessageLite & message)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
InlineMergeFromCodedStream(io::CodedInputStream * input,MessageLite * message)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
InlineParseFromCodedStream(io::CodedInputStream * input,MessageLite * message)129 bool InlineParseFromCodedStream(io::CodedInputStream* input,
130 MessageLite* message) {
131 message->Clear();
132 return InlineMergeFromCodedStream(input, message);
133 }
134
InlineParsePartialFromCodedStream(io::CodedInputStream * input,MessageLite * message)135 bool InlineParsePartialFromCodedStream(io::CodedInputStream* input,
136 MessageLite* message) {
137 message->Clear();
138 return message->MergePartialFromCodedStream(input);
139 }
140
InlineParseFromArray(const void * data,int size,MessageLite * message)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
InlineParsePartialFromArray(const void * data,int size,MessageLite * message)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
MergeFromCodedStream(io::CodedInputStream * input)156 bool MessageLite::MergeFromCodedStream(io::CodedInputStream* input) {
157 return InlineMergeFromCodedStream(input, this);
158 }
159
ParseFromCodedStream(io::CodedInputStream * input)160 bool MessageLite::ParseFromCodedStream(io::CodedInputStream* input) {
161 return InlineParseFromCodedStream(input, this);
162 }
163
ParsePartialFromCodedStream(io::CodedInputStream * input)164 bool MessageLite::ParsePartialFromCodedStream(io::CodedInputStream* input) {
165 return InlineParsePartialFromCodedStream(input, this);
166 }
167
ParseFromZeroCopyStream(io::ZeroCopyInputStream * input)168 bool MessageLite::ParseFromZeroCopyStream(io::ZeroCopyInputStream* input) {
169 io::CodedInputStream decoder(input);
170 return ParseFromCodedStream(&decoder) && decoder.ConsumedEntireMessage();
171 }
172
ParsePartialFromZeroCopyStream(io::ZeroCopyInputStream * input)173 bool MessageLite::ParsePartialFromZeroCopyStream(
174 io::ZeroCopyInputStream* input) {
175 io::CodedInputStream decoder(input);
176 return ParsePartialFromCodedStream(&decoder) &&
177 decoder.ConsumedEntireMessage();
178 }
179
ParseFromBoundedZeroCopyStream(io::ZeroCopyInputStream * input,int size)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
ParsePartialFromBoundedZeroCopyStream(io::ZeroCopyInputStream * input,int size)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
ParseFromString(const string & data)198 bool MessageLite::ParseFromString(const string& data) {
199 return InlineParseFromArray(data.data(), data.size(), this);
200 }
201
ParsePartialFromString(const string & data)202 bool MessageLite::ParsePartialFromString(const string& data) {
203 return InlineParsePartialFromArray(data.data(), data.size(), this);
204 }
205
ParseFromArray(const void * data,int size)206 bool MessageLite::ParseFromArray(const void* data, int size) {
207 return InlineParseFromArray(data, size, this);
208 }
209
ParsePartialFromArray(const void * data,int size)210 bool MessageLite::ParsePartialFromArray(const void* data, int size) {
211 return InlineParsePartialFromArray(data, size, this);
212 }
213
214
215 // ===================================================================
216
SerializeWithCachedSizesToArray(uint8 * target) const217 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
SerializeToCodedStream(io::CodedOutputStream * output) const228 bool MessageLite::SerializeToCodedStream(io::CodedOutputStream* output) const {
229 GOOGLE_DCHECK(IsInitialized()) << InitializationErrorMessage("serialize", *this);
230 return SerializePartialToCodedStream(output);
231 }
232
SerializePartialToCodedStream(io::CodedOutputStream * output) const233 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
SerializeToZeroCopyStream(io::ZeroCopyOutputStream * output) const260 bool MessageLite::SerializeToZeroCopyStream(
261 io::ZeroCopyOutputStream* output) const {
262 io::CodedOutputStream encoder(output);
263 return SerializeToCodedStream(&encoder);
264 }
265
SerializePartialToZeroCopyStream(io::ZeroCopyOutputStream * output) const266 bool MessageLite::SerializePartialToZeroCopyStream(
267 io::ZeroCopyOutputStream* output) const {
268 io::CodedOutputStream encoder(output);
269 return SerializePartialToCodedStream(&encoder);
270 }
271
AppendToString(string * output) const272 bool MessageLite::AppendToString(string* output) const {
273 GOOGLE_DCHECK(IsInitialized()) << InitializationErrorMessage("serialize", *this);
274 return AppendPartialToString(output);
275 }
276
AppendPartialToString(string * output) const277 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
SerializeToString(string * output) const289 bool MessageLite::SerializeToString(string* output) const {
290 output->clear();
291 return AppendToString(output);
292 }
293
SerializePartialToString(string * output) const294 bool MessageLite::SerializePartialToString(string* output) const {
295 output->clear();
296 return AppendPartialToString(output);
297 }
298
SerializeToArray(void * data,int size) const299 bool MessageLite::SerializeToArray(void* data, int size) const {
300 GOOGLE_DCHECK(IsInitialized()) << InitializationErrorMessage("serialize", *this);
301 return SerializePartialToArray(data, size);
302 }
303
SerializePartialToArray(void * data,int size) const304 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
SerializeAsString() const315 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
SerializePartialAsString() const326 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