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 // Author: kenton@google.com (Kenton Varda)
32 // atenasio@google.com (Chris Atenasio) (ZigZag transform)
33 // Based on original Protocol Buffers design by
34 // Sanjay Ghemawat, Jeff Dean, and others.
35 //
36 // This header is logically internal, but is made public because it is used
37 // from protocol-compiler-generated code, which may reside in other components.
38
39 #ifndef GOOGLE_PROTOBUF_WIRE_FORMAT_H__
40 #define GOOGLE_PROTOBUF_WIRE_FORMAT_H__
41
42 #include <string>
43 #include <google/protobuf/descriptor.pb.h>
44 #include <google/protobuf/descriptor.h>
45 #include <google/protobuf/message.h>
46 #include <google/protobuf/wire_format_lite.h>
47
48 // Do UTF-8 validation on string type in Debug build only
49 #ifndef NDEBUG
50 #define GOOGLE_PROTOBUF_UTF8_VALIDATION_ENABLED
51 #endif
52
53 namespace google {
54 namespace protobuf {
55 namespace io {
56 class CodedInputStream; // coded_stream.h
57 class CodedOutputStream; // coded_stream.h
58 }
59 class UnknownFieldSet; // unknown_field_set.h
60 }
61
62 namespace protobuf {
63 namespace internal {
64
65 // This class is for internal use by the protocol buffer library and by
66 // protocol-complier-generated message classes. It must not be called
67 // directly by clients.
68 //
69 // This class contains code for implementing the binary protocol buffer
70 // wire format via reflection. The WireFormatLite class implements the
71 // non-reflection based routines.
72 //
73 // This class is really a namespace that contains only static methods
74 class LIBPROTOBUF_EXPORT WireFormat {
75 public:
76
77 // Given a field return its WireType
78 static inline WireFormatLite::WireType WireTypeForField(
79 const FieldDescriptor* field);
80
81 // Given a FieldSescriptor::Type return its WireType
82 static inline WireFormatLite::WireType WireTypeForFieldType(
83 FieldDescriptor::Type type);
84
85 // Compute the byte size of a tag. For groups, this includes both the start
86 // and end tags.
87 static inline int TagSize(int field_number, FieldDescriptor::Type type);
88
89 // These procedures can be used to implement the methods of Message which
90 // handle parsing and serialization of the protocol buffer wire format
91 // using only the Reflection interface. When you ask the protocol
92 // compiler to optimize for code size rather than speed, it will implement
93 // those methods in terms of these procedures. Of course, these are much
94 // slower than the specialized implementations which the protocol compiler
95 // generates when told to optimize for speed.
96
97 // Read a message in protocol buffer wire format.
98 //
99 // This procedure reads either to the end of the input stream or through
100 // a WIRETYPE_END_GROUP tag ending the message, whichever comes first.
101 // It returns false if the input is invalid.
102 //
103 // Required fields are NOT checked by this method. You must call
104 // IsInitialized() on the resulting message yourself.
105 static bool ParseAndMergePartial(io::CodedInputStream* input,
106 Message* message);
107
108 // Serialize a message in protocol buffer wire format.
109 //
110 // Any embedded messages within the message must have their correct sizes
111 // cached. However, the top-level message need not; its size is passed as
112 // a parameter to this procedure.
113 //
114 // These return false iff the underlying stream returns a write error.
115 static void SerializeWithCachedSizes(
116 const Message& message,
117 int size, io::CodedOutputStream* output);
118
119 // Implements Message::ByteSize() via reflection. WARNING: The result
120 // of this method is *not* cached anywhere. However, all embedded messages
121 // will have their ByteSize() methods called, so their sizes will be cached.
122 // Therefore, calling this method is sufficient to allow you to call
123 // WireFormat::SerializeWithCachedSizes() on the same object.
124 static int ByteSize(const Message& message);
125
126 // -----------------------------------------------------------------
127 // Helpers for dealing with unknown fields
128
129 // Skips a field value of the given WireType. The input should start
130 // positioned immediately after the tag. If unknown_fields is non-NULL,
131 // the contents of the field will be added to it.
132 static bool SkipField(io::CodedInputStream* input, uint32 tag,
133 UnknownFieldSet* unknown_fields);
134
135 // Reads and ignores a message from the input. If unknown_fields is non-NULL,
136 // the contents will be added to it.
137 static bool SkipMessage(io::CodedInputStream* input,
138 UnknownFieldSet* unknown_fields);
139
140 // Write the contents of an UnknownFieldSet to the output.
141 static void SerializeUnknownFields(const UnknownFieldSet& unknown_fields,
142 io::CodedOutputStream* output);
143 // Same as above, except writing directly to the provided buffer.
144 // Requires that the buffer have sufficient capacity for
145 // ComputeUnknownFieldsSize(unknown_fields).
146 //
147 // Returns a pointer past the last written byte.
148 static uint8* SerializeUnknownFieldsToArray(
149 const UnknownFieldSet& unknown_fields,
150 uint8* target);
151
152 // Same thing except for messages that have the message_set_wire_format
153 // option.
154 static void SerializeUnknownMessageSetItems(
155 const UnknownFieldSet& unknown_fields,
156 io::CodedOutputStream* output);
157 // Same as above, except writing directly to the provided buffer.
158 // Requires that the buffer have sufficient capacity for
159 // ComputeUnknownMessageSetItemsSize(unknown_fields).
160 //
161 // Returns a pointer past the last written byte.
162 static uint8* SerializeUnknownMessageSetItemsToArray(
163 const UnknownFieldSet& unknown_fields,
164 uint8* target);
165
166 // Compute the size of the UnknownFieldSet on the wire.
167 static int ComputeUnknownFieldsSize(const UnknownFieldSet& unknown_fields);
168
169 // Same thing except for messages that have the message_set_wire_format
170 // option.
171 static int ComputeUnknownMessageSetItemsSize(
172 const UnknownFieldSet& unknown_fields);
173
174
175 // Helper functions for encoding and decoding tags. (Inlined below and in
176 // _inl.h)
177 //
178 // This is different from MakeTag(field->number(), field->type()) in the case
179 // of packed repeated fields.
180 static uint32 MakeTag(const FieldDescriptor* field);
181
182 // Parse a single field. The input should start out positioned immidately
183 // after the tag.
184 static bool ParseAndMergeField(
185 uint32 tag,
186 const FieldDescriptor* field, // May be NULL for unknown
187 Message* message,
188 io::CodedInputStream* input);
189
190 // Serialize a single field.
191 static void SerializeFieldWithCachedSizes(
192 const FieldDescriptor* field, // Cannot be NULL
193 const Message& message,
194 io::CodedOutputStream* output);
195
196 // Compute size of a single field. If the field is a message type, this
197 // will call ByteSize() for the embedded message, insuring that it caches
198 // its size.
199 static int FieldByteSize(
200 const FieldDescriptor* field, // Cannot be NULL
201 const Message& message);
202
203 // Parse/serialize a MessageSet::Item group. Used with messages that use
204 // opion message_set_wire_format = true.
205 static bool ParseAndMergeMessageSetItem(
206 io::CodedInputStream* input,
207 Message* message);
208 static void SerializeMessageSetItemWithCachedSizes(
209 const FieldDescriptor* field,
210 const Message& message,
211 io::CodedOutputStream* output);
212 static int MessageSetItemByteSize(
213 const FieldDescriptor* field,
214 const Message& message);
215
216 // Computes the byte size of a field, excluding tags. For packed fields, it
217 // only includes the size of the raw data, and not the size of the total
218 // length, but for other length-delimited types, the size of the length is
219 // included.
220 static int FieldDataOnlyByteSize(
221 const FieldDescriptor* field, // Cannot be NULL
222 const Message& message);
223
224 enum Operation {
225 PARSE,
226 SERIALIZE,
227 };
228
229 // Verifies that a string field is valid UTF8, logging an error if not.
230 static void VerifyUTF8String(const char* data, int size, Operation op);
231
232 private:
233 // Verifies that a string field is valid UTF8, logging an error if not.
234 static void VerifyUTF8StringFallback(
235 const char* data,
236 int size,
237 Operation op);
238
239
240
241 GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(WireFormat);
242 };
243
244 // Subclass of FieldSkipper which saves skipped fields to an UnknownFieldSet.
245 class LIBPROTOBUF_EXPORT UnknownFieldSetFieldSkipper : public FieldSkipper {
246 public:
UnknownFieldSetFieldSkipper(UnknownFieldSet * unknown_fields)247 UnknownFieldSetFieldSkipper(UnknownFieldSet* unknown_fields)
248 : unknown_fields_(unknown_fields) {}
~UnknownFieldSetFieldSkipper()249 virtual ~UnknownFieldSetFieldSkipper() {}
250
251 // implements FieldSkipper -----------------------------------------
252 virtual bool SkipField(io::CodedInputStream* input, uint32 tag);
253 virtual bool SkipMessage(io::CodedInputStream* input);
254 virtual void SkipUnknownEnum(int field_number, int value);
255
256 private:
257 UnknownFieldSet* unknown_fields_;
258 };
259
260 // inline methods ====================================================
261
WireTypeForField(const FieldDescriptor * field)262 inline WireFormatLite::WireType WireFormat::WireTypeForField(
263 const FieldDescriptor* field) {
264 if (field->options().packed()) {
265 return WireFormatLite::WIRETYPE_LENGTH_DELIMITED;
266 } else {
267 return WireTypeForFieldType(field->type());
268 }
269 }
270
WireTypeForFieldType(FieldDescriptor::Type type)271 inline WireFormatLite::WireType WireFormat::WireTypeForFieldType(
272 FieldDescriptor::Type type) {
273 // Some compilers don't like enum -> enum casts, so we implicit_cast to
274 // int first.
275 return WireFormatLite::WireTypeForFieldType(
276 static_cast<WireFormatLite::FieldType>(
277 implicit_cast<int>(type)));
278 }
279
MakeTag(const FieldDescriptor * field)280 inline uint32 WireFormat::MakeTag(const FieldDescriptor* field) {
281 return WireFormatLite::MakeTag(field->number(), WireTypeForField(field));
282 }
283
TagSize(int field_number,FieldDescriptor::Type type)284 inline int WireFormat::TagSize(int field_number, FieldDescriptor::Type type) {
285 // Some compilers don't like enum -> enum casts, so we implicit_cast to
286 // int first.
287 return WireFormatLite::TagSize(field_number,
288 static_cast<WireFormatLite::FieldType>(
289 implicit_cast<int>(type)));
290 }
291
VerifyUTF8String(const char * data,int size,WireFormat::Operation op)292 inline void WireFormat::VerifyUTF8String(const char* data, int size,
293 WireFormat::Operation op) {
294 #ifdef GOOGLE_PROTOBUF_UTF8_VALIDATION_ENABLED
295 WireFormat::VerifyUTF8StringFallback(data, size, op);
296 #endif
297 }
298
299
300 } // namespace internal
301 } // namespace protobuf
302
303 } // namespace google
304 #endif // GOOGLE_PROTOBUF_WIRE_FORMAT_H__
305