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 // This file contains miscellaneous helper code used by generated code --
36 // including lite types -- but which should not be used directly by users.
37
38 #ifndef GOOGLE_PROTOBUF_GENERATED_MESSAGE_UTIL_H__
39 #define GOOGLE_PROTOBUF_GENERATED_MESSAGE_UTIL_H__
40
41 #include <assert.h>
42
43 #include <atomic>
44 #include <climits>
45 #include <string>
46 #include <vector>
47
48 #include <google/protobuf/stubs/common.h>
49 #include <google/protobuf/any.h>
50 #include <google/protobuf/has_bits.h>
51 #include <google/protobuf/implicit_weak_message.h>
52 #include <google/protobuf/message_lite.h>
53 #include <google/protobuf/stubs/once.h> // Add direct dep on port for pb.cc
54 #include <google/protobuf/port.h>
55 #include <google/protobuf/repeated_field.h>
56 #include <google/protobuf/wire_format_lite.h>
57 #include <google/protobuf/stubs/strutil.h>
58 #include <google/protobuf/stubs/casts.h>
59
60 #include <google/protobuf/port_def.inc>
61
62 #ifdef SWIG
63 #error "You cannot SWIG proto headers"
64 #endif
65
66 namespace google {
67 namespace protobuf {
68
69 class Arena;
70 class Message;
71
72 namespace io {
73 class CodedInputStream;
74 }
75
76 namespace internal {
77
78 template <typename To, typename From>
DownCast(From * f)79 inline To DownCast(From* f) {
80 return PROTOBUF_NAMESPACE_ID::internal::down_cast<To>(f);
81 }
82 template <typename To, typename From>
DownCast(From & f)83 inline To DownCast(From& f) {
84 return PROTOBUF_NAMESPACE_ID::internal::down_cast<To>(f);
85 }
86
87
88 PROTOBUF_EXPORT void InitProtobufDefaults();
89
90 // This used by proto1
GetEmptyString()91 PROTOBUF_EXPORT inline const std::string& GetEmptyString() {
92 InitProtobufDefaults();
93 return GetEmptyStringAlreadyInited();
94 }
95
96
97 // True if IsInitialized() is true for all elements of t. Type is expected
98 // to be a RepeatedPtrField<some message type>. It's useful to have this
99 // helper here to keep the protobuf compiler from ever having to emit loops in
100 // IsInitialized() methods. We want the C++ compiler to inline this or not
101 // as it sees fit.
102 template <typename Msg>
AllAreInitialized(const RepeatedPtrField<Msg> & t)103 bool AllAreInitialized(const RepeatedPtrField<Msg>& t) {
104 for (int i = t.size(); --i >= 0;) {
105 if (!t.Get(i).IsInitialized()) return false;
106 }
107 return true;
108 }
109
110 // "Weak" variant of AllAreInitialized, used to implement implicit weak fields.
111 // This version operates on MessageLite to avoid introducing a dependency on the
112 // concrete message type.
113 template <class T>
AllAreInitializedWeak(const RepeatedPtrField<T> & t)114 bool AllAreInitializedWeak(const RepeatedPtrField<T>& t) {
115 for (int i = t.size(); --i >= 0;) {
116 if (!reinterpret_cast<const RepeatedPtrFieldBase&>(t)
117 .Get<ImplicitWeakTypeHandler<T> >(i)
118 .IsInitialized()) {
119 return false;
120 }
121 }
122 return true;
123 }
124
IsPresent(const void * base,uint32 hasbit)125 inline bool IsPresent(const void* base, uint32 hasbit) {
126 const uint32* has_bits_array = static_cast<const uint32*>(base);
127 return (has_bits_array[hasbit / 32] & (1u << (hasbit & 31))) != 0;
128 }
129
IsOneofPresent(const void * base,uint32 offset,uint32 tag)130 inline bool IsOneofPresent(const void* base, uint32 offset, uint32 tag) {
131 const uint32* oneof =
132 reinterpret_cast<const uint32*>(static_cast<const uint8*>(base) + offset);
133 return *oneof == tag >> 3;
134 }
135
136 typedef void (*SpecialSerializer)(const uint8* base, uint32 offset, uint32 tag,
137 uint32 has_offset,
138 io::CodedOutputStream* output);
139
140 PROTOBUF_EXPORT void ExtensionSerializer(const uint8* base, uint32 offset,
141 uint32 tag, uint32 has_offset,
142 io::CodedOutputStream* output);
143 PROTOBUF_EXPORT void UnknownFieldSerializerLite(const uint8* base,
144 uint32 offset, uint32 tag,
145 uint32 has_offset,
146 io::CodedOutputStream* output);
147
148 PROTOBUF_EXPORT MessageLite* DuplicateIfNonNullInternal(MessageLite* message);
149 PROTOBUF_EXPORT MessageLite* GetOwnedMessageInternal(Arena* message_arena,
150 MessageLite* submessage,
151 Arena* submessage_arena);
152 PROTOBUF_EXPORT void GenericSwap(MessageLite* m1, MessageLite* m2);
153 // We specialize GenericSwap for non-lite messages to benefit from reflection.
154 PROTOBUF_EXPORT void GenericSwap(Message* m1, Message* m2);
155
156 template <typename T>
DuplicateIfNonNull(T * message)157 T* DuplicateIfNonNull(T* message) {
158 // The casts must be reinterpret_cast<> because T might be a forward-declared
159 // type that the compiler doesn't know is related to MessageLite.
160 return reinterpret_cast<T*>(
161 DuplicateIfNonNullInternal(reinterpret_cast<MessageLite*>(message)));
162 }
163
164 template <typename T>
GetOwnedMessage(Arena * message_arena,T * submessage,Arena * submessage_arena)165 T* GetOwnedMessage(Arena* message_arena, T* submessage,
166 Arena* submessage_arena) {
167 // The casts must be reinterpret_cast<> because T might be a forward-declared
168 // type that the compiler doesn't know is related to MessageLite.
169 return reinterpret_cast<T*>(GetOwnedMessageInternal(
170 message_arena, reinterpret_cast<MessageLite*>(submessage),
171 submessage_arena));
172 }
173
174 // Hide atomic from the public header and allow easy change to regular int
175 // on platforms where the atomic might have a perf impact.
176 class PROTOBUF_EXPORT CachedSize {
177 public:
Get()178 int Get() const { return size_.load(std::memory_order_relaxed); }
Set(int size)179 void Set(int size) { size_.store(size, std::memory_order_relaxed); }
180
181 private:
182 std::atomic<int> size_{0};
183 };
184
185 // SCCInfo represents information of a strongly connected component of
186 // mutual dependent messages.
187 struct PROTOBUF_EXPORT SCCInfoBase {
188 // We use 0 for the Initialized state, because test eax,eax, jnz is smaller
189 // and is subject to macro fusion.
190 enum {
191 kInitialized = 0, // final state
192 kRunning = 1,
193 kUninitialized = -1, // initial state
194 };
195 #if defined(_MSC_VER) && !defined(__clang__)
196 // MSVC doesn't make std::atomic constant initialized. This union trick
197 // makes it so.
198 union {
199 int visit_status_to_make_linker_init;
200 std::atomic<int> visit_status;
201 };
202 #else
203 std::atomic<int> visit_status;
204 #endif
205 int num_deps;
206 int num_implicit_weak_deps;
207 void (*init_func)();
208 // This is followed by an array of num_deps
209 // const SCCInfoBase* deps[];
210 };
211
212 // Zero-length arrays are a language extension available in GCC and Clang but
213 // not MSVC.
214 #ifdef __GNUC__
215 #define PROTOBUF_ARRAY_SIZE(n) (n)
216 #else
217 #define PROTOBUF_ARRAY_SIZE(n) ((n) ? (n) : 1)
218 #endif
219
220 template <int N>
221 struct SCCInfo {
222 SCCInfoBase base;
223 // Semantically this is const SCCInfo<T>* which is is a templated type.
224 // The obvious inheriting from SCCInfoBase mucks with struct initialization.
225 // Attempts showed the compiler was generating dynamic initialization code.
226 // This deps array consists of base.num_deps pointers to SCCInfoBase followed
227 // by base.num_implicit_weak_deps pointers to SCCInfoBase*. We need the extra
228 // pointer indirection for implicit weak fields. We cannot use a union type
229 // here, since that would prevent the array from being linker-initialized.
230 void* deps[PROTOBUF_ARRAY_SIZE(N)];
231 };
232
233 #undef PROTOBUF_ARRAY_SIZE
234
235 PROTOBUF_EXPORT void InitSCCImpl(SCCInfoBase* scc);
236
InitSCC(SCCInfoBase * scc)237 inline void InitSCC(SCCInfoBase* scc) {
238 auto status = scc->visit_status.load(std::memory_order_acquire);
239 if (PROTOBUF_PREDICT_FALSE(status != SCCInfoBase::kInitialized))
240 InitSCCImpl(scc);
241 }
242
243 PROTOBUF_EXPORT void DestroyMessage(const void* message);
244 PROTOBUF_EXPORT void DestroyString(const void* s);
245 // Destroy (not delete) the message
OnShutdownDestroyMessage(const void * ptr)246 inline void OnShutdownDestroyMessage(const void* ptr) {
247 OnShutdownRun(DestroyMessage, ptr);
248 }
249 // Destroy the string (call std::string destructor)
OnShutdownDestroyString(const std::string * ptr)250 inline void OnShutdownDestroyString(const std::string* ptr) {
251 OnShutdownRun(DestroyString, ptr);
252 }
253
254 } // namespace internal
255 } // namespace protobuf
256 } // namespace google
257
258 #include <google/protobuf/port_undef.inc>
259
260 #endif // GOOGLE_PROTOBUF_GENERATED_MESSAGE_UTIL_H__
261