1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef IPC_IPC_MESSAGE_H_ 6 #define IPC_IPC_MESSAGE_H_ 7 8 #include <stddef.h> 9 #include <stdint.h> 10 11 #include <string> 12 13 #include "base/gtest_prod_util.h" 14 #include "base/memory/ref_counted.h" 15 #include "base/pickle.h" 16 #include "base/trace_event/trace_event.h" 17 #include "build/build_config.h" 18 #include "ipc/ipc_buildflags.h" 19 #include "ipc/ipc_message_support_export.h" 20 21 namespace mojo { 22 namespace internal { 23 struct UnmappedNativeStructSerializerImpl; 24 } 25 } // namespace mojo 26 27 namespace IPC { 28 29 namespace internal { 30 class ChannelReader; 31 } // namespace internal 32 33 //------------------------------------------------------------------------------ 34 35 struct LogData; 36 class MessageAttachmentSet; 37 38 class IPC_MESSAGE_SUPPORT_EXPORT Message : public base::Pickle { 39 public: 40 enum PriorityValue { 41 PRIORITY_LOW = 1, 42 PRIORITY_NORMAL, 43 PRIORITY_HIGH 44 }; 45 46 // Bit values used in the flags field. 47 // Upper 24 bits of flags store a reference number, so this enum is limited to 48 // 8 bits. 49 enum { 50 PRIORITY_MASK = 0x03, // Low 2 bits of store the priority value. 51 SYNC_BIT = 0x04, 52 REPLY_BIT = 0x08, 53 REPLY_ERROR_BIT = 0x10, 54 UNBLOCK_BIT = 0x20, 55 PUMPING_MSGS_BIT = 0x40, 56 HAS_SENT_TIME_BIT = 0x80, 57 }; 58 59 ~Message() override; 60 61 Message(); 62 63 // Initialize a message with a user-defined type, priority value, and 64 // destination WebView ID. 65 Message(int32_t routing_id, uint32_t type, PriorityValue priority); 66 67 // Initializes a message from a const block of data. The data is not copied; 68 // instead the data is merely referenced by this message. Only const methods 69 // should be used on the message when initialized this way. 70 Message(const char* data, int data_len); 71 72 Message(const Message& other); 73 Message& operator=(const Message& other); 74 75 bool IsValid() const { return header_size() == sizeof(Header) && header(); } 76 77 PriorityValue priority() const { 78 return static_cast<PriorityValue>(header()->flags & PRIORITY_MASK); 79 } 80 81 // True if this is a synchronous message. 82 void set_sync() { 83 header()->flags |= SYNC_BIT; 84 } 85 bool is_sync() const { 86 return (header()->flags & SYNC_BIT) != 0; 87 } 88 89 // Set this on a reply to a synchronous message. 90 void set_reply() { 91 header()->flags |= REPLY_BIT; 92 } 93 94 bool is_reply() const { 95 return (header()->flags & REPLY_BIT) != 0; 96 } 97 98 // Set this on a reply to a synchronous message to indicate that no receiver 99 // was found. 100 void set_reply_error() { 101 header()->flags |= REPLY_ERROR_BIT; 102 } 103 104 bool is_reply_error() const { 105 return (header()->flags & REPLY_ERROR_BIT) != 0; 106 } 107 108 // Normally when a receiver gets a message and they're blocked on a 109 // synchronous message Send, they buffer a message. Setting this flag causes 110 // the receiver to be unblocked and the message to be dispatched immediately. 111 void set_unblock(bool unblock) { 112 if (unblock) { 113 header()->flags |= UNBLOCK_BIT; 114 } else { 115 header()->flags &= ~UNBLOCK_BIT; 116 } 117 } 118 119 bool should_unblock() const { 120 return (header()->flags & UNBLOCK_BIT) != 0; 121 } 122 123 // Tells the receiver that the caller is pumping messages while waiting 124 // for the result. 125 bool is_caller_pumping_messages() const { 126 return (header()->flags & PUMPING_MSGS_BIT) != 0; 127 } 128 129 void set_dispatch_error() const { 130 dispatch_error_ = true; 131 } 132 133 bool dispatch_error() const { 134 return dispatch_error_; 135 } 136 137 uint32_t type() const { 138 return header()->type; 139 } 140 141 int32_t routing_id() const { 142 return header()->routing; 143 } 144 145 void set_routing_id(int32_t new_id) { 146 header()->routing = new_id; 147 } 148 149 uint32_t flags() const { 150 return header()->flags; 151 } 152 153 // Sets all the given header values. The message should be empty at this 154 // call. 155 void SetHeaderValues(int32_t routing, uint32_t type, uint32_t flags); 156 157 template<class T, class S, class P> 158 static bool Dispatch(const Message* msg, T* obj, S* sender, P* parameter, 159 void (T::*func)()) { 160 (obj->*func)(); 161 return true; 162 } 163 164 template<class T, class S, class P> 165 static bool Dispatch(const Message* msg, T* obj, S* sender, P* parameter, 166 void (T::*func)(P*)) { 167 (obj->*func)(parameter); 168 return true; 169 } 170 171 // Used for async messages with no parameters. 172 static void Log(std::string* name, const Message* msg, std::string* l) { 173 } 174 175 // The static method FindNext() returns several pieces of information, which 176 // are aggregated into an instance of this struct. 177 struct IPC_MESSAGE_SUPPORT_EXPORT NextMessageInfo { 178 NextMessageInfo(); 179 ~NextMessageInfo(); 180 181 // Total message size. Always valid if |message_found| is true. 182 // If |message_found| is false but we could determine message size 183 // from the header, this field is non-zero. Otherwise it's zero. 184 size_t message_size; 185 // Whether an entire message was found in the given memory range. 186 bool message_found; 187 // Only filled in if |message_found| is true. 188 // The start address is passed into FindNext() by the caller, so isn't 189 // repeated in this struct. The end address of the pickle should be used to 190 // construct a base::Pickle. 191 const char* pickle_end; 192 // Only filled in if |message_found| is true. 193 // The end address of the message should be used to determine the start 194 // address of the next message. 195 const char* message_end; 196 }; 197 198 // |info| is an output parameter and must not be nullptr. 199 static void FindNext(const char* range_start, 200 const char* range_end, 201 NextMessageInfo* info); 202 203 // WriteAttachment appends |attachment| to the end of the set. It returns 204 // false iff the set is full. 205 bool WriteAttachment( 206 scoped_refptr<base::Pickle::Attachment> attachment) override; 207 // ReadAttachment parses an attachment given the parsing state |iter| and 208 // writes it to |*attachment|. It returns true on success. 209 bool ReadAttachment( 210 base::PickleIterator* iter, 211 scoped_refptr<base::Pickle::Attachment>* attachment) const override; 212 // Returns true if there are any attachment in this message. 213 bool HasAttachments() const override; 214 215 #if BUILDFLAG(IPC_MESSAGE_LOG_ENABLED) 216 // Adds the outgoing time from Time::Now() at the end of the message and sets 217 // a bit to indicate that it's been added. 218 void set_sent_time(int64_t time); 219 int64_t sent_time() const; 220 221 void set_received_time(int64_t time) const; 222 int64_t received_time() const { return received_time_; } 223 void set_output_params(const std::string& op) const { output_params_ = op; } 224 const std::string& output_params() const { return output_params_; } 225 // The following four functions are needed so we can log sync messages with 226 // delayed replies. We stick the log data from the sent message into the 227 // reply message, so that when it's sent and we have the output parameters 228 // we can log it. As such, we set a flag on the sent message to not log it. 229 void set_sync_log_data(LogData* data) const { log_data_ = data; } 230 LogData* sync_log_data() const { return log_data_; } 231 void set_dont_log() const { dont_log_ = true; } 232 bool dont_log() const { return dont_log_; } 233 #endif 234 235 protected: 236 friend class Channel; 237 friend class ChannelMojo; 238 friend class ChannelNacl; 239 friend class ChannelPosix; 240 friend class ChannelWin; 241 friend class internal::ChannelReader; 242 friend class MessageReplyDeserializer; 243 friend class SyncMessage; 244 245 friend struct mojo::internal::UnmappedNativeStructSerializerImpl; 246 247 #pragma pack(push, 4) 248 struct Header : base::Pickle::Header { 249 int32_t routing; // ID of the view that this message is destined for 250 uint32_t type; // specifies the user-defined message type 251 uint32_t flags; // specifies control flags for the message 252 #if defined(OS_POSIX) || defined(OS_FUCHSIA) 253 uint16_t num_fds; // the number of descriptors included with this message 254 uint16_t pad; // explicitly initialize this to appease valgrind 255 #endif 256 }; 257 #pragma pack(pop) 258 259 Header* header() { 260 return headerT<Header>(); 261 } 262 const Header* header() const { 263 return headerT<Header>(); 264 } 265 266 void Init(); 267 268 // Used internally to support IPC::Listener::OnBadMessageReceived. 269 mutable bool dispatch_error_; 270 271 // The set of file descriptors associated with this message. 272 scoped_refptr<MessageAttachmentSet> attachment_set_; 273 274 // Ensure that a MessageAttachmentSet is allocated 275 void EnsureMessageAttachmentSet(); 276 277 MessageAttachmentSet* attachment_set() { 278 EnsureMessageAttachmentSet(); 279 return attachment_set_.get(); 280 } 281 const MessageAttachmentSet* attachment_set() const { 282 return attachment_set_.get(); 283 } 284 285 #if BUILDFLAG(IPC_MESSAGE_LOG_ENABLED) 286 // Used for logging. 287 mutable int64_t received_time_; 288 mutable std::string output_params_; 289 mutable LogData* log_data_; 290 mutable bool dont_log_; 291 #endif 292 293 FRIEND_TEST_ALL_PREFIXES(IPCMessageTest, FindNext); 294 FRIEND_TEST_ALL_PREFIXES(IPCMessageTest, FindNextOverflow); 295 }; 296 297 //------------------------------------------------------------------------------ 298 299 } // namespace IPC 300 301 enum SpecialRoutingIDs { 302 // indicates that we don't have a routing ID yet. 303 MSG_ROUTING_NONE = -2, 304 305 // indicates a general message not sent to a particular tab. 306 MSG_ROUTING_CONTROL = INT32_MAX, 307 }; 308 309 #define IPC_REPLY_ID 0xFFFFFFF0 // Special message id for replies 310 #define IPC_LOGGING_ID 0xFFFFFFF1 // Special message id for logging 311 312 #endif // IPC_IPC_MESSAGE_H_ 313