1 // Protocol Buffers - Google's data interchange format
2 // Copyright 2008 Google Inc.  All rights reserved.
3 // https://developers.google.com/protocol-buffers/
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 //  Based on original Protocol Buffers design by
33 //  Sanjay Ghemawat, Jeff Dean, and others.
34 //
35 // Contains classes used to keep track of unrecognized fields seen while
36 // parsing a protocol message.
37 
38 #ifndef GOOGLE_PROTOBUF_UNKNOWN_FIELD_SET_H__
39 #define GOOGLE_PROTOBUF_UNKNOWN_FIELD_SET_H__
40 
41 #include <assert.h>
42 #include <string>
43 #include <vector>
44 #include <google/protobuf/stubs/common.h>
45 
46 namespace google {
47 namespace protobuf {
48   namespace io {
49     class CodedInputStream;         // coded_stream.h
50     class CodedOutputStream;        // coded_stream.h
51     class ZeroCopyInputStream;      // zero_copy_stream.h
52   }
53   namespace internal {
54     class WireFormat;               // wire_format.h
55     class MessageSetFieldSkipperUsingCord;
56                                     // extension_set_heavy.cc
57   }
58 
59 class Message;                      // message.h
60 class UnknownField;                 // below
61 
62 // An UnknownFieldSet contains fields that were encountered while parsing a
63 // message but were not defined by its type.  Keeping track of these can be
64 // useful, especially in that they may be written if the message is serialized
65 // again without being cleared in between.  This means that software which
66 // simply receives messages and forwards them to other servers does not need
67 // to be updated every time a new field is added to the message definition.
68 //
69 // To get the UnknownFieldSet attached to any message, call
70 // Reflection::GetUnknownFields().
71 //
72 // This class is necessarily tied to the protocol buffer wire format, unlike
73 // the Reflection interface which is independent of any serialization scheme.
74 class LIBPROTOBUF_EXPORT UnknownFieldSet {
75  public:
76   UnknownFieldSet();
77   ~UnknownFieldSet();
78 
79   // Remove all fields.
80   inline void Clear();
81 
82   // Remove all fields and deallocate internal data objects
83   void ClearAndFreeMemory();
84 
85   // Is this set empty?
86   inline bool empty() const;
87 
88   // Merge the contents of some other UnknownFieldSet with this one.
89   void MergeFrom(const UnknownFieldSet& other);
90 
91   // Swaps the contents of some other UnknownFieldSet with this one.
92   inline void Swap(UnknownFieldSet* x);
93 
94   // Computes (an estimate of) the total number of bytes currently used for
95   // storing the unknown fields in memory. Does NOT include
96   // sizeof(*this) in the calculation.
97   int SpaceUsedExcludingSelf() const;
98 
99   // Version of SpaceUsed() including sizeof(*this).
100   int SpaceUsed() const;
101 
102   // Returns the number of fields present in the UnknownFieldSet.
103   inline int field_count() const;
104   // Get a field in the set, where 0 <= index < field_count().  The fields
105   // appear in the order in which they were added.
106   inline const UnknownField& field(int index) const;
107   // Get a mutable pointer to a field in the set, where
108   // 0 <= index < field_count().  The fields appear in the order in which
109   // they were added.
110   inline UnknownField* mutable_field(int index);
111 
112   // Adding fields ---------------------------------------------------
113 
114   void AddVarint(int number, uint64 value);
115   void AddFixed32(int number, uint32 value);
116   void AddFixed64(int number, uint64 value);
117   void AddLengthDelimited(int number, const string& value);
118   string* AddLengthDelimited(int number);
119   UnknownFieldSet* AddGroup(int number);
120 
121   // Adds an unknown field from another set.
122   void AddField(const UnknownField& field);
123 
124   // Delete fields with indices in the range [start .. start+num-1].
125   // Caution: implementation moves all fields with indices [start+num .. ].
126   void DeleteSubrange(int start, int num);
127 
128   // Delete all fields with a specific field number. The order of left fields
129   // is preserved.
130   // Caution: implementation moves all fields after the first deleted field.
131   void DeleteByNumber(int number);
132 
133   // Parsing helpers -------------------------------------------------
134   // These work exactly like the similarly-named methods of Message.
135 
136   bool MergeFromCodedStream(io::CodedInputStream* input);
137   bool ParseFromCodedStream(io::CodedInputStream* input);
138   bool ParseFromZeroCopyStream(io::ZeroCopyInputStream* input);
139   bool ParseFromArray(const void* data, int size);
ParseFromString(const string & data)140   inline bool ParseFromString(const string& data) {
141     return ParseFromArray(data.data(), static_cast<int>(data.size()));
142   }
143 
144  private:
145 
146   void ClearFallback();
147 
148   std::vector<UnknownField>* fields_;
149 
150   GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(UnknownFieldSet);
151 };
152 
153 // Represents one field in an UnknownFieldSet.
154 class LIBPROTOBUF_EXPORT UnknownField {
155  public:
156   enum Type {
157     TYPE_VARINT,
158     TYPE_FIXED32,
159     TYPE_FIXED64,
160     TYPE_LENGTH_DELIMITED,
161     TYPE_GROUP
162   };
163 
164   // The field's tag number, as seen on the wire.
165   inline int number() const;
166 
167   // The field type.
168   inline Type type() const;
169 
170   // Accessors -------------------------------------------------------
171   // Each method works only for UnknownFields of the corresponding type.
172 
173   inline uint64 varint() const;
174   inline uint32 fixed32() const;
175   inline uint64 fixed64() const;
176   inline const string& length_delimited() const;
177   inline const UnknownFieldSet& group() const;
178 
179   inline void set_varint(uint64 value);
180   inline void set_fixed32(uint32 value);
181   inline void set_fixed64(uint64 value);
182   inline void set_length_delimited(const string& value);
183   inline string* mutable_length_delimited();
184   inline UnknownFieldSet* mutable_group();
185 
186   // Serialization API.
187   // These methods can take advantage of the underlying implementation and may
188   // archieve a better performance than using getters to retrieve the data and
189   // do the serialization yourself.
190   void SerializeLengthDelimitedNoTag(io::CodedOutputStream* output) const;
191   uint8* SerializeLengthDelimitedNoTagToArray(uint8* target) const;
192 
193   inline int GetLengthDelimitedSize() const;
194 
195  private:
196   friend class UnknownFieldSet;
197 
198   // If this UnknownField contains a pointer, delete it.
199   void Delete();
200 
201   // Make a deep copy of any pointers in this UnknownField.
202   void DeepCopy();
203 
204   // Set the wire type of this UnknownField. Should only be used when this
205   // UnknownField is being created.
206   inline void SetType(Type type);
207 
208   uint32 number_;
209   uint32 type_;
210   union {
211     uint64 varint_;
212     uint32 fixed32_;
213     uint64 fixed64_;
214     mutable union {
215       string* string_value_;
216     } length_delimited_;
217     UnknownFieldSet* group_;
218   };
219 };
220 
221 // ===================================================================
222 // inline implementations
223 
Clear()224 inline void UnknownFieldSet::Clear() {
225   if (fields_ != NULL) {
226     ClearFallback();
227   }
228 }
229 
empty()230 inline bool UnknownFieldSet::empty() const {
231   return fields_ == NULL || fields_->empty();
232 }
233 
Swap(UnknownFieldSet * x)234 inline void UnknownFieldSet::Swap(UnknownFieldSet* x) {
235   std::swap(fields_, x->fields_);
236 }
237 
field_count()238 inline int UnknownFieldSet::field_count() const {
239   return (fields_ == NULL) ? 0 : static_cast<int>(fields_->size());
240 }
field(int index)241 inline const UnknownField& UnknownFieldSet::field(int index) const {
242   return (*fields_)[index];
243 }
mutable_field(int index)244 inline UnknownField* UnknownFieldSet::mutable_field(int index) {
245   return &(*fields_)[index];
246 }
247 
AddLengthDelimited(int number,const string & value)248 inline void UnknownFieldSet::AddLengthDelimited(
249     int number, const string& value) {
250   AddLengthDelimited(number)->assign(value);
251 }
252 
253 
number()254 inline int UnknownField::number() const { return number_; }
type()255 inline UnknownField::Type UnknownField::type() const {
256   return static_cast<Type>(type_);
257 }
258 
varint()259 inline uint64 UnknownField::varint() const {
260   assert(type() == TYPE_VARINT);
261   return varint_;
262 }
fixed32()263 inline uint32 UnknownField::fixed32() const {
264   assert(type() == TYPE_FIXED32);
265   return fixed32_;
266 }
fixed64()267 inline uint64 UnknownField::fixed64() const {
268   assert(type() == TYPE_FIXED64);
269   return fixed64_;
270 }
length_delimited()271 inline const string& UnknownField::length_delimited() const {
272   assert(type() == TYPE_LENGTH_DELIMITED);
273   return *length_delimited_.string_value_;
274 }
group()275 inline const UnknownFieldSet& UnknownField::group() const {
276   assert(type() == TYPE_GROUP);
277   return *group_;
278 }
279 
set_varint(uint64 value)280 inline void UnknownField::set_varint(uint64 value) {
281   assert(type() == TYPE_VARINT);
282   varint_ = value;
283 }
set_fixed32(uint32 value)284 inline void UnknownField::set_fixed32(uint32 value) {
285   assert(type() == TYPE_FIXED32);
286   fixed32_ = value;
287 }
set_fixed64(uint64 value)288 inline void UnknownField::set_fixed64(uint64 value) {
289   assert(type() == TYPE_FIXED64);
290   fixed64_ = value;
291 }
set_length_delimited(const string & value)292 inline void UnknownField::set_length_delimited(const string& value) {
293   assert(type() == TYPE_LENGTH_DELIMITED);
294   length_delimited_.string_value_->assign(value);
295 }
mutable_length_delimited()296 inline string* UnknownField::mutable_length_delimited() {
297   assert(type() == TYPE_LENGTH_DELIMITED);
298   return length_delimited_.string_value_;
299 }
mutable_group()300 inline UnknownFieldSet* UnknownField::mutable_group() {
301   assert(type() == TYPE_GROUP);
302   return group_;
303 }
304 
GetLengthDelimitedSize()305 inline int UnknownField::GetLengthDelimitedSize() const {
306   GOOGLE_DCHECK_EQ(TYPE_LENGTH_DELIMITED, type());
307   return static_cast<int>(length_delimited_.string_value_->size());
308 }
309 
SetType(Type type)310 inline void UnknownField::SetType(Type type) {
311   type_ = type;
312 }
313 
314 
315 }  // namespace protobuf
316 
317 }  // namespace google
318 #endif  // GOOGLE_PROTOBUF_UNKNOWN_FIELD_SET_H__
319