ipc/ipc_message_macros.h

   1 // Copyright (c) 2011 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 // Defining IPC Messages
   6 //
   7 // Your IPC messages will be defined by macros inside of an XXX_messages.h
   8 // header file.  Most of the time, the system can automatically generate all
   9 // of messaging mechanism from these definitions, but sometimes some manual
  10 // coding is required.  In these cases, you will also have an XXX_messages.cc
  11 // implemation file as well.
  12 //
  13 // The senders of your messages will include your XXX_messages.h file to
  14 // get the full set of definitions they need to send your messages.
  15 //
  16 // Each XXX_messages.h file must be registered with the IPC system.  This
  17 // requires adding two things:
  18 //   - An XXXMsgStart value to the IPCMessageStart enum in ipc_message_utils.h
  19 //   - An inclusion of XXX_messages.h file in a message generator .h file
  20 //
  21 // The XXXMsgStart value is an enumeration that ensures uniqueness for
  22 // each different message file.  Later, you will use this inside your
  23 // XXX_messages.h file before invoking message declatation macros:
  24 //     #define IPC_MESSAGE_START XXXMsgStart
  25 //       ( ... your macro invocations go here ... )
  26 //
  27 // Message Generator Files
  28 //
  29 // A message generator .h header file pulls in all other message-declaring
  30 // headers for a given component.  It is included by a message generator
  31 // .cc file, which is where all the generated code will wind up.  Typically,
  32 // you will use an existing generator (e.g. common_message_generator.cc
  33 // in /chrome/common), but there are circumstances where you may add a
  34 // new one.
  35 //
  36 // In the rare cicrucmstances where you can't re-use an existing file,
  37 // your YYY_message_generator.cc file for a component YYY would contain
  38 // the following code:
  39 //     // Get basic type definitions.
  40 //     #define IPC_MESSAGE_IMPL
  41 //     #include "path/to/YYY_message_generator.h"
  42 //     // Generate constructors.
  43 //     #include "ipc/struct_constructor_macros.h"
  44 //     #include "path/to/YYY_message_generator.h"
  45 //     // Generate destructors.
  46 //     #include "ipc/struct_destructor_macros.h"
  47 //     #include "path/to/YYY_message_generator.h"
  48 //     // Generate param traits write methods.
  49 //     #include "ipc/param_traits_write_macros.h"
  50 //     namespace IPC {
  51 //     #include "path/to/YYY_message_generator.h"
  52 //     }  // namespace IPC
  53 //     // Generate param traits read methods.
  54 //     #include "ipc/param_traits_read_macros.h"
  55 //     namespace IPC {
  56 //     #include "path/to/YYY_message_generator.h"
  57 //     }  // namespace IPC
  58 //     // Generate param traits log methods.
  59 //     #include "ipc/param_traits_log_macros.h"
  60 //     namespace IPC {
  61 //     #include "path/to/YYY_message_generator.h"
  62 //     }  // namespace IPC
  63 //
  64 // In cases where manual generation is required, in your XXX_messages.cc
  65 // file, put the following after all the includes for param types:
  66 //     #define IPC_MESSAGE_IMPL
  67 //     #include "XXX_messages.h"
  68 //        (... implementation of traits not auto-generated ...)
  69 //
  70 // Multiple Inclusion
  71 //
  72 // The XXX_messages.h file will be multiply-included by the
  73 // YYY_message_generator.cc file, so your XXX_messages file can't be
  74 // guarded in the usual manner.  Ideally, there will be no need for any
  75 // inclusion guard, since the XXX_messages.h file should consist soley
  76 // of inclusions of other headers (which are self-guarding) and IPC
  77 // macros (which are multiply evaluating).
  78 //
  79 // Note that there is no #pragma once either; doing so would mark the whole
  80 // file as being singly-included.  Since your XXX_messages.h file is only
  81 // partially-guarded, care must be taken to ensure that it is only included
  82 // by other .cc files (and the YYY_message_generator.h file).  Including an
  83 // XXX_messages.h file in some other .h file may result in duplicate
  84 // declarations and a compilation failure.
  85 //
  86 // Type Declarations
  87 //
  88 // It is generally a bad idea to have type definitions in a XXX_messages.h
  89 // file; most likely the typedef will then be used in the message, as opposed
  90 // to the struct iself.  Later, an IPC message dispatcher wil need to call
  91 // a function taking that type, and that function is declared in some other
  92 // header.  Thus, in order to get the type definition, the other header
  93 // would have to include the XXX_messages.h file, violating the rule above
  94 // about not including XXX_messages.h file in other .h files.
  95 //
  96 // One approach here is to move these type definitions to another (guarded)
  97 // .h file and include this second .h in your XXX_messages.h file.  This
  98 // is still less than ideal, because the dispatched function would have to
  99 // redeclare the typedef or include this second header.  This may be
 100 // reasonable in a few cases.
 101 //
 102 // Failing all of the above, then you will want to bracket the smallest
 103 // possible section of your XXX_messages.h file containing these types
 104 // with an include guard macro.  Be aware that providing an incomplete
 105 // class type declaration to avoid pulling in a long chain of headers is
 106 // acceptable when your XXX_messages.h header is being included by the
 107 // message sending caller's code, but not when the YYY_message_generator.c
 108 // is building the messages. In addtion, due to the multiple inclusion
 109 // restriction, these type ought to be guarded.  Follow a convention like:
 110 //      #ifndef SOME_GUARD_MACRO
 111 //      #define SOME_GUARD_MACRO
 112 //      class some_class;        // One incomplete class declaration
 113 //      class_some_other_class;  // Another incomplete class declaration
 114 //      #endif  // SOME_GUARD_MACRO
 115 //      #ifdef IPC_MESSAGE_IMPL
 116 //      #inlcude "path/to/some_class.h"        // Full class declaration
 117 //      #inlcude "path/to/some_other_class.h"  // Full class declaration
 118 //      #endif  // IPC_MESSAGE_IMPL
 119 //        (.. IPC macros using some_class and some_other_class ...)
 120 //
 121 // Macro Invocations
 122 //
 123 // You will use IPC message macro invocations for three things:
 124 //   - New struct definitions for IPC
 125 //   - Registering existing struct and enum definitions with IPC
 126 //   - Defining the messages themselves
 127 //
 128 // New structs are defined with IPC_STRUCT_BEGIN(), IPC_STRUCT_MEMBER(),
 129 // IPC_STRUCT_END() family of macros.  These cause the XXX_messages.h
 130 // to proclaim equivalent struct declarations for use by callers, as well
 131 // as later registering the type with the message generation.  Note that
 132 // IPC_STRUCT_MEMBER() is only permitted inside matching calls to
 133 // IPC_STRUCT_BEGIN() / IPC_STRUCT_END().
 134 //
 135 // Externally-defined structs are registered with IPC_STRUCT_TRAITS_BEGIN(),
 136 // IPC_STRUCT_TRAITS_MEMBER(), and IPC_STRUCT_TRAITS_END() macros. These
 137 // cause registration of the types with message generation only.
 138 // There's also IPC_STRUCT_TRAITS_PARENT, which is used to register a parent
 139 // class (whose own traits are already defined). Note that
 140 // IPC_STRUCT_TRAITS_MEMBER() and IPC_STRUCT_TRAITS_PARENT are only permitted
 141 // inside matching calls to IPC_STRUCT_TRAITS_BEGIN() /
 142 // IPC_STRUCT_TRAITS_END().
 143 //
 144 // Enum types are registered with a single IPC_ENUM_TRAITS() macro.  There
 145 // is no need to enumerate each value to the IPC mechanism.
 146 //
 147 // Do not place semicolons following these IPC_ macro invocations.  There
 148 // is no reason to expect that their expansion corresponds one-to-one with
 149 // C++ statements.
 150 //
 151 // Once the types have been declared / registered, message definitions follow.
 152 // "Sync" messages are just synchronous calls, the Send() call doesn't return
 153 // until a reply comes back.  Input parameters are first (const TYPE&), and
 154 // To declare a sync message, use the IPC_SYNC_ macros.  The numbers at the
 155 // end show how many input/output parameters there are (i.e. 1_2 is 1 in, 2
 156 // out). The caller does a Send([route id, ], in1, &out1, &out2).
 157 // The receiver's handler function will be
 158 //     void OnSyncMessageName(const type1& in1, type2* out1, type3* out2)
 159 //
 160 // A caller can also send a synchronous message, while the receiver can respond
 161 // at a later time.  This is transparent from the sender's side.  The receiver
 162 // needs to use a different handler that takes in a IPC::Message* as the output
 163 // type, stash the message, and when it has the data it can Send the message.
 164 //
 165 // Use the IPC_MESSAGE_HANDLER_DELAY_REPLY macro instead of IPC_MESSAGE_HANDLER
 166 //     IPC_MESSAGE_HANDLER_DELAY_REPLY(ViewHostMsg_SyncMessageName,
 167 //                                     OnSyncMessageName)
 168 //
 169 // The handler function will look like:
 170 //     void OnSyncMessageName(const type1& in1, IPC::Message* reply_msg);
 171 //
 172 // Receiver stashes the IPC::Message* pointer, and when it's ready, it does:
 173 //     ViewHostMsg_SyncMessageName::WriteReplyParams(reply_msg, out1, out2);
 174 //     Send(reply_msg);
 175
 176 #ifndef IPC_IPC_MESSAGE_MACROS_H_
 177 #define IPC_IPC_MESSAGE_MACROS_H_
 178
 179 #include "ipc/ipc_message_utils.h"
 180 #include "ipc/param_traits_macros.h"
 181
 182 #if defined(IPC_MESSAGE_IMPL)
 183 #include "ipc/ipc_message_utils_impl.h"
 184 #endif
 185
 186 // Macros for defining structs.  May be subsequently redefined.
 187 #define IPC_STRUCT_BEGIN(struct_name) \
 188   struct struct_name; \
 189   IPC_STRUCT_TRAITS_BEGIN(struct_name) \
 190   IPC_STRUCT_TRAITS_END() \
 191   struct struct_name : IPC::NoParams { \
 192     struct_name(); \
 193     ~struct_name();
 194 #define IPC_STRUCT_MEMBER(type, name) type name;
 195 #define IPC_STRUCT_END() };
 196
 197 // Message macros collect specific numbers of arguments and funnel them into
 198 // the common message generation macro.  These should never be redefined.
 199 #define IPC_MESSAGE_CONTROL0(msg_class) \
 200   IPC_MESSAGE_DECL(EMPTY, CONTROL, msg_class, 0, 0, (), ())
 201
 202 #define IPC_MESSAGE_CONTROL1(msg_class, type1) \
 203   IPC_MESSAGE_DECL(ASYNC, CONTROL, msg_class, 1, 0, (type1), ())
 204
 205 #define IPC_MESSAGE_CONTROL2(msg_class, type1, type2) \
 206   IPC_MESSAGE_DECL(ASYNC, CONTROL, msg_class, 2, 0, (type1, type2), ())
 207
 208 #define IPC_MESSAGE_CONTROL3(msg_class, type1, type2, type3) \
 209   IPC_MESSAGE_DECL(ASYNC, CONTROL, msg_class, 3, 0, (type1, type2, type3), ())
 210
 211 #define IPC_MESSAGE_CONTROL4(msg_class, type1, type2, type3, type4) \
 212   IPC_MESSAGE_DECL(ASYNC, CONTROL, msg_class, 4, 0, (type1, type2, type3, type4), ())
 213
 214 #define IPC_MESSAGE_CONTROL5(msg_class, type1, type2, type3, type4, type5) \
 215   IPC_MESSAGE_DECL(ASYNC, CONTROL, msg_class, 5, 0, (type1, type2, type3, type4, type5), ())
 216
 217 #define IPC_MESSAGE_CONTROL6(msg_class, type1, type2, type3, type4, type5, type6) \
 218         IPC_MESSAGE_DECL(ASYNC, CONTROL, msg_class, 6, 0, (type1, type2, type3, type4, type5, type6), ())
 219
 220
 221 #define IPC_MESSAGE_ROUTED0(msg_class) \
 222   IPC_MESSAGE_DECL(EMPTY, ROUTED, msg_class, 0, 0, (), ())
 223
 224 #define IPC_MESSAGE_ROUTED1(msg_class, type1) \
 225   IPC_MESSAGE_DECL(ASYNC, ROUTED, msg_class, 1, 0, (type1), ())
 226
 227 #define IPC_MESSAGE_ROUTED2(msg_class, type1, type2) \
 228   IPC_MESSAGE_DECL(ASYNC, ROUTED, msg_class, 2, 0, (type1, type2), ())
 229
 230 #define IPC_MESSAGE_ROUTED3(msg_class, type1, type2, type3) \
 231   IPC_MESSAGE_DECL(ASYNC, ROUTED, msg_class, 3, 0, (type1, type2, type3), ())
 232
 233 #define IPC_MESSAGE_ROUTED4(msg_class, type1, type2, type3, type4) \
 234   IPC_MESSAGE_DECL(ASYNC, ROUTED, msg_class, 4, 0, (type1, type2, type3, type4), ())
 235
 236 #define IPC_MESSAGE_ROUTED5(msg_class, type1, type2, type3, type4, type5) \
 237   IPC_MESSAGE_DECL(ASYNC, ROUTED, msg_class, 5, 0, (type1, type2, type3, type4, type5), ())
 238
 239 #define IPC_MESSAGE_ROUTED6(msg_class, type1, type2, type3, type4, type5, type6) \
 240         IPC_MESSAGE_DECL(ASYNC, ROUTED, msg_class, 6, 0, (type1, type2, type3, type4, type5, type6), ())
 241
 242 #define IPC_SYNC_MESSAGE_CONTROL0_0(msg_class) \
 243   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 0, 0, (), ())
 244
 245 #define IPC_SYNC_MESSAGE_CONTROL0_1(msg_class, type1_out) \
 246   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 0, 1, (), (type1_out))
 247
 248 #define IPC_SYNC_MESSAGE_CONTROL0_2(msg_class, type1_out, type2_out) \
 249   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 0, 2, (), (type1_out, type2_out))
 250
 251 #define IPC_SYNC_MESSAGE_CONTROL0_3(msg_class, type1_out, type2_out, type3_out) \
 252   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 0, 3, (), (type1_out, type2_out, type3_out))
 253
 254 #define IPC_SYNC_MESSAGE_CONTROL0_4(msg_class, type1_out, type2_out, type3_out, type4_out) \
 255   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 0, 4, (), (type1_out, type2_out, type3_out, type4_out))
 256
 257 #define IPC_SYNC_MESSAGE_CONTROL1_0(msg_class, type1_in) \
 258   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 1, 0, (type1_in), ())
 259
 260 #define IPC_SYNC_MESSAGE_CONTROL1_1(msg_class, type1_in, type1_out) \
 261   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 1, 1, (type1_in), (type1_out))
 262
 263 #define IPC_SYNC_MESSAGE_CONTROL1_2(msg_class, type1_in, type1_out, type2_out) \
 264   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 1, 2, (type1_in), (type1_out, type2_out))
 265
 266 #define IPC_SYNC_MESSAGE_CONTROL1_3(msg_class, type1_in, type1_out, type2_out, type3_out) \
 267   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 1, 3, (type1_in), (type1_out, type2_out, type3_out))
 268
 269 #define IPC_SYNC_MESSAGE_CONTROL1_4(msg_class, type1_in, type1_out, type2_out, type3_out, type4_out) \
 270   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 1, 4, (type1_in), (type1_out, type2_out, type3_out, type4_out))
 271
 272 #define IPC_SYNC_MESSAGE_CONTROL2_0(msg_class, type1_in, type2_in) \
 273   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 2, 0, (type1_in, type2_in), ())
 274
 275 #define IPC_SYNC_MESSAGE_CONTROL2_1(msg_class, type1_in, type2_in, type1_out) \
 276   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 2, 1, (type1_in, type2_in), (type1_out))
 277
 278 #define IPC_SYNC_MESSAGE_CONTROL2_2(msg_class, type1_in, type2_in, type1_out, type2_out) \
 279   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 2, 2, (type1_in, type2_in), (type1_out, type2_out))
 280
 281 #define IPC_SYNC_MESSAGE_CONTROL2_3(msg_class, type1_in, type2_in, type1_out, type2_out, type3_out) \
 282   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 2, 3, (type1_in, type2_in), (type1_out, type2_out, type3_out))
 283
 284 #define IPC_SYNC_MESSAGE_CONTROL2_4(msg_class, type1_in, type2_in, type1_out, type2_out, type3_out, type4_out) \
 285   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 2, 4, (type1_in, type2_in), (type1_out, type2_out, type3_out, type4_out))
 286
 287 #define IPC_SYNC_MESSAGE_CONTROL3_0(msg_class, type1_in, type2_in, type3_in) \
 288   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 3, 0, (type1_in, type2_in, type3_in), ())
 289
 290 #define IPC_SYNC_MESSAGE_CONTROL3_1(msg_class, type1_in, type2_in, type3_in, type1_out) \
 291   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 3, 1, (type1_in, type2_in, type3_in), (type1_out))
 292
 293 #define IPC_SYNC_MESSAGE_CONTROL3_2(msg_class, type1_in, type2_in, type3_in, type1_out, type2_out) \
 294   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 3, 2, (type1_in, type2_in, type3_in), (type1_out, type2_out))
 295
 296 #define IPC_SYNC_MESSAGE_CONTROL3_3(msg_class, type1_in, type2_in, type3_in, type1_out, type2_out, type3_out) \
 297   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 3, 3, (type1_in, type2_in, type3_in), (type1_out, type2_out, type3_out))
 298
 299 #define IPC_SYNC_MESSAGE_CONTROL3_4(msg_class, type1_in, type2_in, type3_in, type1_out, type2_out, type3_out, type4_out) \
 300   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 3, 4, (type1_in, type2_in, type3_in), (type1_out, type2_out, type3_out, type4_out))
 301
 302 #define IPC_SYNC_MESSAGE_CONTROL4_0(msg_class, type1_in, type2_in, type3_in, type4_in) \
 303   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 4, 0, (type1_in, type2_in, type3_in, type4_in), ())
 304
 305 #define IPC_SYNC_MESSAGE_CONTROL4_1(msg_class, type1_in, type2_in, type3_in, type4_in, type1_out) \
 306   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 4, 1, (type1_in, type2_in, type3_in, type4_in), (type1_out))
 307
 308 #define IPC_SYNC_MESSAGE_CONTROL4_2(msg_class, type1_in, type2_in, type3_in, type4_in, type1_out, type2_out) \
 309   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 4, 2, (type1_in, type2_in, type3_in, type4_in), (type1_out, type2_out))
 310
 311 #define IPC_SYNC_MESSAGE_CONTROL4_3(msg_class, type1_in, type2_in, type3_in, type4_in, type1_out, type2_out, type3_out) \
 312   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 4, 3, (type1_in, type2_in, type3_in, type4_in), (type1_out, type2_out, type3_out))
 313
 314 #define IPC_SYNC_MESSAGE_CONTROL4_4(msg_class, type1_in, type2_in, type3_in, type4_in, type1_out, type2_out, type3_out, type4_out) \
 315   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 4, 4, (type1_in, type2_in, type3_in, type4_in), (type1_out, type2_out, type3_out, type4_out))
 316
 317 #define IPC_SYNC_MESSAGE_CONTROL5_0(msg_class, type1_in, type2_in, type3_in, type4_in, type5_in) \
 318   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 5, 0, (type1_in, type2_in, type3_in, type4_in, type5_in), ())
 319
 320 #define IPC_SYNC_MESSAGE_CONTROL5_1(msg_class, type1_in, type2_in, type3_in, type4_in, type5_in, type1_out) \
 321   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 5, 1, (type1_in, type2_in, type3_in, type4_in, type5_in), (type1_out))
 322
 323 #define IPC_SYNC_MESSAGE_CONTROL5_2(msg_class, type1_in, type2_in, type3_in, type4_in, type5_in, type1_out, type2_out) \
 324   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 5, 2, (type1_in, type2_in, type3_in, type4_in, type5_in), (type1_out, type2_out))
 325
 326 #define IPC_SYNC_MESSAGE_CONTROL5_3(msg_class, type1_in, type2_in, type3_in, type4_in, type5_in, type1_out, type2_out, type3_out) \
 327   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 5, 3, (type1_in, type2_in, type3_in, type4_in, type5_in), (type1_out, type2_out, type3_out))
 328
 329 #define IPC_SYNC_MESSAGE_CONTROL5_4(msg_class, type1_in, type2_in, type3_in, type4_in, type5_in, type1_out, type2_out, type3_out, type4_out) \
 330   IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 5, 4, (type1_in, type2_in, type3_in, type4_in, type5_in), (type1_out, type2_out, type3_out, type4_out))
 331
 332 #define IPC_SYNC_MESSAGE_CONTROL6_0(msg_class, type1_in, type2_in, type3_in, type4_in, type5_in, type6_in) \
 333         IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 6, 0, (type1_in, type2_in, type3_in, type4_in, type5_in, type6_in), ())
 334
 335 #define IPC_SYNC_MESSAGE_CONTROL6_1(msg_class, type1_in, type2_in, type3_in, type4_in, type5_in, type6_in, type1_out) \
 336         IPC_MESSAGE_DECL(SYNC, CONTROL, msg_class, 6, 1, (type1_in, type2_in, type3_in, type4_in, type5_in, type6_in), (type1_out))
 337
 338 #define IPC_SYNC_MESSAGE_ROUTED0_0(msg_class) \
 339   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 0, 0, (), ())
 340
 341 #define IPC_SYNC_MESSAGE_ROUTED0_1(msg_class, type1_out) \
 342   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 0, 1, (), (type1_out))
 343
 344 #define IPC_SYNC_MESSAGE_ROUTED0_2(msg_class, type1_out, type2_out) \
 345   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 0, 2, (), (type1_out, type2_out))
 346
 347 #define IPC_SYNC_MESSAGE_ROUTED0_3(msg_class, type1_out, type2_out, type3_out) \
 348   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 0, 3, (), (type1_out, type2_out, type3_out))
 349
 350 #define IPC_SYNC_MESSAGE_ROUTED0_4(msg_class, type1_out, type2_out, type3_out, type4_out) \
 351   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 0, 4, (), (type1_out, type2_out, type3_out, type4_out))
 352
 353 #define IPC_SYNC_MESSAGE_ROUTED1_0(msg_class, type1_in) \
 354   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 1, 0, (type1_in), ())
 355
 356 #define IPC_SYNC_MESSAGE_ROUTED1_1(msg_class, type1_in, type1_out) \
 357   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 1, 1, (type1_in), (type1_out))
 358
 359 #define IPC_SYNC_MESSAGE_ROUTED1_2(msg_class, type1_in, type1_out, type2_out) \
 360   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 1, 2, (type1_in), (type1_out, type2_out))
 361
 362 #define IPC_SYNC_MESSAGE_ROUTED1_3(msg_class, type1_in, type1_out, type2_out, type3_out) \
 363   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 1, 3, (type1_in), (type1_out, type2_out, type3_out))
 364
 365 #define IPC_SYNC_MESSAGE_ROUTED1_4(msg_class, type1_in, type1_out, type2_out, type3_out, type4_out) \
 366   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 1, 4, (type1_in), (type1_out, type2_out, type3_out, type4_out))
 367
 368 #define IPC_SYNC_MESSAGE_ROUTED2_0(msg_class, type1_in, type2_in) \
 369   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 2, 0, (type1_in, type2_in), ())
 370
 371 #define IPC_SYNC_MESSAGE_ROUTED2_1(msg_class, type1_in, type2_in, type1_out) \
 372   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 2, 1, (type1_in, type2_in), (type1_out))
 373
 374 #define IPC_SYNC_MESSAGE_ROUTED2_2(msg_class, type1_in, type2_in, type1_out, type2_out) \
 375   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 2, 2, (type1_in, type2_in), (type1_out, type2_out))
 376
 377 #define IPC_SYNC_MESSAGE_ROUTED2_3(msg_class, type1_in, type2_in, type1_out, type2_out, type3_out) \
 378   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 2, 3, (type1_in, type2_in), (type1_out, type2_out, type3_out))
 379
 380 #define IPC_SYNC_MESSAGE_ROUTED2_4(msg_class, type1_in, type2_in, type1_out, type2_out, type3_out, type4_out) \
 381   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 2, 4, (type1_in, type2_in), (type1_out, type2_out, type3_out, type4_out))
 382
 383 #define IPC_SYNC_MESSAGE_ROUTED3_0(msg_class, type1_in, type2_in, type3_in) \
 384   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 3, 0, (type1_in, type2_in, type3_in), ())
 385
 386 #define IPC_SYNC_MESSAGE_ROUTED3_1(msg_class, type1_in, type2_in, type3_in, type1_out) \
 387   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 3, 1, (type1_in, type2_in, type3_in), (type1_out))
 388
 389 #define IPC_SYNC_MESSAGE_ROUTED3_2(msg_class, type1_in, type2_in, type3_in, type1_out, type2_out) \
 390   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 3, 2, (type1_in, type2_in, type3_in), (type1_out, type2_out))
 391
 392 #define IPC_SYNC_MESSAGE_ROUTED3_3(msg_class, type1_in, type2_in, type3_in, type1_out, type2_out, type3_out) \
 393   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 3, 3, (type1_in, type2_in, type3_in), (type1_out, type2_out, type3_out))
 394
 395 #define IPC_SYNC_MESSAGE_ROUTED3_4(msg_class, type1_in, type2_in, type3_in, type1_out, type2_out, type3_out, type4_out) \
 396   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 3, 4, (type1_in, type2_in, type3_in), (type1_out, type2_out, type3_out, type4_out))
 397
 398 #define IPC_SYNC_MESSAGE_ROUTED4_0(msg_class, type1_in, type2_in, type3_in, type4_in) \
 399   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 4, 1, (type1_in, type2_in, type3_in, type4_in), ())
 400
 401 #define IPC_SYNC_MESSAGE_ROUTED4_1(msg_class, type1_in, type2_in, type3_in, type4_in, type1_out) \
 402   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 4, 1, (type1_in, type2_in, type3_in, type4_in), (type1_out))
 403
 404 #define IPC_SYNC_MESSAGE_ROUTED4_2(msg_class, type1_in, type2_in, type3_in, type4_in, type1_out, type2_out) \
 405   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 4, 2, (type1_in, type2_in, type3_in, type4_in), (type1_out, type2_out))
 406
 407 #define IPC_SYNC_MESSAGE_ROUTED4_3(msg_class, type1_in, type2_in, type3_in, type4_in, type1_out, type2_out, type3_out) \
 408   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 4, 3, (type1_in, type2_in, type3_in, type4_in), (type1_out, type2_out, type3_out))
 409
 410 #define IPC_SYNC_MESSAGE_ROUTED4_4(msg_class, type1_in, type2_in, type3_in, type4_in, type1_out, type2_out, type3_out, type4_out) \
 411   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 4, 4, (type1_in, type2_in, type3_in, type4_in), (type1_out, type2_out, type3_out, type4_out))
 412
 413 #define IPC_SYNC_MESSAGE_ROUTED5_0(msg_class, type1_in, type2_in, type3_in, type4_in, type5_in) \
 414   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 5, 1, (type1_in, type2_in, type3_in, type4_in, type5_in), ())
 415
 416 #define IPC_SYNC_MESSAGE_ROUTED5_1(msg_class, type1_in, type2_in, type3_in, type4_in, type5_in, type1_out) \
 417   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 5, 1, (type1_in, type2_in, type3_in, type4_in, type5_in), (type1_out))
 418
 419 #define IPC_SYNC_MESSAGE_ROUTED5_2(msg_class, type1_in, type2_in, type3_in, type4_in, type5_in, type1_out, type2_out) \
 420   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 5, 2, (type1_in, type2_in, type3_in, type4_in, type5_in), (type1_out, type2_out))
 421
 422 #define IPC_SYNC_MESSAGE_ROUTED5_3(msg_class, type1_in, type2_in, type3_in, type4_in, type5_in, type1_out, type2_out, type3_out) \
 423   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 5, 3, (type1_in, type2_in, type3_in, type4_in, type5_in), (type1_out, type2_out, type3_out))
 424
 425 #define IPC_SYNC_MESSAGE_ROUTED5_4(msg_class, type1_in, type2_in, type3_in, type4_in, type5_in, type1_out, type2_out, type3_out, type4_out) \
 426   IPC_MESSAGE_DECL(SYNC, ROUTED, msg_class, 5, 4, (type1_in, type2_in, type3_in, type4_in, type5_in), (type1_out, type2_out, type3_out, type4_out))
 427
 428 // Common message macro which dispatches into one of the 6 (sync x kind)
 429 // routines.  There is a way that these 6 cases can be lumped together,
 430 // but the  macros get very complicated in that case.
 431 // Note: intended be redefined to generate other information.
 432 #define IPC_MESSAGE_DECL(sync, kind, msg_class,                               \
 433                          in_cnt, out_cnt, in_list, out_list)                  \
 434   IPC_##sync##_##kind##_DECL(msg_class, in_cnt, out_cnt, in_list, out_list)   \
 435   IPC_MESSAGE_EXTRA(sync, kind, msg_class, in_cnt, out_cnt, in_list, out_list)
 436
 437 #define IPC_EMPTY_CONTROL_DECL(msg_class, in_cnt, out_cnt, in_list, out_list) \
 438   class __attribute__((visibility("default"))) msg_class : public IPC::Message\
 439   {                                                                           \
 440    public:                                                                    \
 441     enum { ID = IPC_MESSAGE_ID() };                                           \
 442     msg_class() : IPC::Message(MSG_ROUTING_CONTROL, ID, PRIORITY_NORMAL) {}   \
 443   };
 444
 445 #define IPC_EMPTY_ROUTED_DECL(msg_class, in_cnt, out_cnt, in_list, out_list)  \
 446   class __attribute__((visibility("default"))) msg_class : public IPC::Message\
 447   {                                                                           \
 448    public:                                                                    \
 449     enum { ID = IPC_MESSAGE_ID() };                                           \
 450     msg_class(int32 routing_id)                                               \
 451         : IPC::Message(routing_id, ID, PRIORITY_NORMAL) {}                    \
 452   };
 453
 454 #define IPC_ASYNC_CONTROL_DECL(msg_class, in_cnt, out_cnt, in_list, out_list) \
 455   class __attribute__((visibility("default"))) msg_class :                    \
 456       public IPC::MessageWithTuple<IPC_TUPLE_IN_##in_cnt in_list> {           \
 457    public:                                                                    \
 458     enum { ID = IPC_MESSAGE_ID() };                                           \
 459     msg_class(IPC_TYPE_IN_##in_cnt in_list);                                  \
 460     virtual ~msg_class();                                                     \
 461     static void Log(std::string* name, const Message* msg, std::string* l);   \
 462   };
 463
 464 #define IPC_ASYNC_ROUTED_DECL(msg_class, in_cnt, out_cnt, in_list, out_list)  \
 465   class __attribute__((visibility("default"))) msg_class :                    \
 466       public IPC::MessageWithTuple<IPC_TUPLE_IN_##in_cnt in_list> {           \
 467    public:                                                                    \
 468     enum { ID = IPC_MESSAGE_ID() };                                           \
 469     msg_class(int32 routing_id IPC_COMMA_##in_cnt                             \
 470               IPC_TYPE_IN_##in_cnt in_list);                                  \
 471     virtual ~msg_class();                                                     \
 472     static void Log(std::string* name, const Message* msg, std::string* l);   \
 473   };
 474
 475 #define IPC_SYNC_CONTROL_DECL(msg_class, in_cnt, out_cnt, in_list, out_list)  \
 476   class __attribute__((visibility("default"))) msg_class :                    \
 477       public IPC::MessageWithReply<IPC_TUPLE_IN_##in_cnt in_list,             \
 478                                    IPC_TUPLE_OUT_##out_cnt out_list> {        \
 479    public:                                                                    \
 480     enum { ID = IPC_MESSAGE_ID() };                                           \
 481     msg_class(IPC_TYPE_IN_##in_cnt in_list                                    \
 482               IPC_COMMA_AND_##in_cnt(IPC_COMMA_##out_cnt)                     \
 483               IPC_TYPE_OUT_##out_cnt out_list);                               \
 484     virtual ~msg_class();                                                     \
 485     static void Log(std::string* name, const Message* msg, std::string* l);   \
 486   };
 487
 488 #define IPC_SYNC_ROUTED_DECL(msg_class, in_cnt, out_cnt, in_list, out_list)   \
 489   class __attribute__((visibility("default"))) msg_class :                    \
 490       public IPC::MessageWithReply<IPC_TUPLE_IN_##in_cnt in_list,             \
 491                                    IPC_TUPLE_OUT_##out_cnt out_list> {        \
 492    public:                                                                    \
 493     enum { ID = IPC_MESSAGE_ID() };                                           \
 494     msg_class(int32 routing_id                                                \
 495               IPC_COMMA_OR_##in_cnt(IPC_COMMA_##out_cnt)                      \
 496               IPC_TYPE_IN_##in_cnt in_list                                    \
 497               IPC_COMMA_AND_##in_cnt(IPC_COMMA_##out_cnt)                     \
 498               IPC_TYPE_OUT_##out_cnt out_list);                               \
 499     virtual ~msg_class();                                                     \
 500     static void Log(std::string* name, const Message* msg, std::string* l);   \
 501   };
 502
 503 #if defined(IPC_MESSAGE_IMPL)
 504
 505 // "Implementation" inclusion produces constructors, destructors, and
 506 // logging functions, except for the no-arg special cases, where the
 507 // implementation occurs in the declaration, and there is no special
 508 // logging function.
 509 #define IPC_MESSAGE_EXTRA(sync, kind, msg_class,                              \
 510                           in_cnt, out_cnt, in_list, out_list)                 \
 511   IPC_##sync##_##kind##_IMPL(msg_class, in_cnt, out_cnt, in_list, out_list)   \
 512   IPC_##sync##_MESSAGE_LOG(msg_class)
 513
 514 #define IPC_EMPTY_CONTROL_IMPL(msg_class, in_cnt, out_cnt, in_list, out_list)
 515 #define IPC_EMPTY_ROUTED_IMPL(msg_class, in_cnt, out_cnt, in_list, out_list)
 516
 517 #define IPC_ASYNC_CONTROL_IMPL(msg_class, in_cnt, out_cnt, in_list, out_list) \
 518   msg_class::msg_class(IPC_TYPE_IN_##in_cnt in_list) :                        \
 519       IPC::MessageWithTuple<IPC_TUPLE_IN_##in_cnt in_list>                    \
 520       (MSG_ROUTING_CONTROL, ID, IPC_NAME_IN_##in_cnt in_list)                 \
 521       {}                                                                      \
 522   msg_class::~msg_class() {}
 523
 524 #define IPC_ASYNC_ROUTED_IMPL(msg_class, in_cnt, out_cnt, in_list, out_list)  \
 525   msg_class::msg_class(int32 routing_id IPC_COMMA_##in_cnt                    \
 526                        IPC_TYPE_IN_##in_cnt in_list) :                        \
 527       IPC::MessageWithTuple<IPC_TUPLE_IN_##in_cnt in_list>                    \
 528       (routing_id, ID, IPC_NAME_IN_##in_cnt in_list)                          \
 529       {}                                                                      \
 530   msg_class::~msg_class() {}
 531
 532 #define IPC_SYNC_CONTROL_IMPL(msg_class, in_cnt, out_cnt, in_list, out_list)  \
 533   msg_class::msg_class(IPC_TYPE_IN_##in_cnt in_list                           \
 534                        IPC_COMMA_AND_##in_cnt(IPC_COMMA_##out_cnt)            \
 535                        IPC_TYPE_OUT_##out_cnt out_list) :                     \
 536       IPC::MessageWithReply<IPC_TUPLE_IN_##in_cnt in_list,                    \
 537                             IPC_TUPLE_OUT_##out_cnt out_list>                 \
 538       (MSG_ROUTING_CONTROL, ID,                                               \
 539        IPC_NAME_IN_##in_cnt in_list,                                          \
 540        IPC_NAME_OUT_##out_cnt out_list)                                       \
 541   {                                                                     \
 542   }                                                                     \
 543   msg_class::~msg_class() {}
 544
 545 #define IPC_SYNC_ROUTED_IMPL(msg_class, in_cnt, out_cnt, in_list, out_list)   \
 546   msg_class::msg_class(int32 routing_id                                       \
 547                        IPC_COMMA_OR_##in_cnt(IPC_COMMA_##out_cnt)             \
 548                        IPC_TYPE_IN_##in_cnt in_list                           \
 549                        IPC_COMMA_AND_##in_cnt(IPC_COMMA_##out_cnt)            \
 550                        IPC_TYPE_OUT_##out_cnt out_list) :                     \
 551       IPC::MessageWithReply<IPC_TUPLE_IN_##in_cnt in_list,                    \
 552                             IPC_TUPLE_OUT_##out_cnt out_list>                 \
 553       (routing_id, ID,                                                        \
 554        IPC_NAME_IN_##in_cnt in_list,                                          \
 555        IPC_NAME_OUT_##out_cnt out_list)                                       \
 556       {}                                                                      \
 557   msg_class::~msg_class() {}
 558
 559 #define IPC_EMPTY_MESSAGE_LOG(msg_class)
 560
 561 #define IPC_ASYNC_MESSAGE_LOG(msg_class)                                \
 562   void msg_class::Log(std::string* name,                                \
 563                       const Message* msg,                               \
 564                       std::string* l) {                                 \
 565     if (name)                                                           \
 566         {                                                                                                                                       \
 567       *name = #msg_class;                                               \
 568         }                                                                                                                                       \
 569     if (!msg || !l)                                                     \
 570         {                                                                                                                                       \
 571       return;                                                           \
 572         }                                                                                                                                       \
 573     Param p;                                                            \
 574     if (Read(msg, &p))                                                  \
 575         {                                                                                                                                       \
 576       IPC::LogParam(p, l);                                              \
 577         }                                                                                                                                       \
 578   }
 579
 580 #define IPC_SYNC_MESSAGE_LOG(msg_class)                                 \
 581   void msg_class::Log(std::string* name,                                \
 582                       const Message* msg,                               \
 583                       std::string* l) {                                 \
 584     if (name)                                                           \
 585         {                                                                                                                                       \
 586       *name = #msg_class;                                               \
 587         }                                                                                                                                       \
 588     if (!msg || !l)                                                     \
 589         {                                                                                                                                       \
 590       return;                                                           \
 591         }                                                                                                                                       \
 592     if (msg->is_sync()) {                                               \
 593       TupleTypes<SendParam>::ValueTuple p;                              \
 594       if (ReadSendParam(msg, &p))                                       \
 595           {                                                                                                                                     \
 596         IPC::LogParam(p, l);                                            \
 597           }                                                                                                                                     \
 598       AddOutputParamsToLog(msg, l);                                     \
 599     } else {                                                            \
 600       TupleTypes<ReplyParam>::ValueTuple p;                             \
 601       if (ReadReplyParam(msg, &p))                                      \
 602           {                                                                                                                                     \
 603         IPC::LogParam(p, l);                                            \
 604           }                                                                                                                                     \
 605     }                                                                   \
 606   }
 607
 608 #elif defined(IPC_MESSAGE_MACROS_LOG_ENABLED)
 609
 610 #ifndef IPC_LOG_TABLE_CREATED
 611 #define IPC_LOG_TABLE_CREATED
 612
 613 #include "base/hash_tables.h"
 614
 615 typedef void (*LogFunction)(std::string* name,
 616                             const IPC::Message* msg,
 617                             std::string* params);
 618
 619 typedef base::hash_map<uint32, LogFunction > LogFunctionMap;
 620 LogFunctionMap g_log_function_mapping;
 621
 622 #endif  // IPC_LOG_TABLE_CREATED
 623
 624 // "Log table" inclusion produces extra logging registration code.
 625 #define IPC_MESSAGE_EXTRA(sync, kind, msg_class,                        \
 626                           in_cnt, out_cnt, in_list, out_list)           \
 627   class __attribute__((visibility("default"))) LoggerRegisterHelper##msg_class { \
 628  public:                                                                \
 629     LoggerRegisterHelper##msg_class() {                                 \
 630       g_log_function_mapping[msg_class::ID] = msg_class::Log;           \
 631     }                                                                   \
 632   };                                                                    \
 633   LoggerRegisterHelper##msg_class g_LoggerRegisterHelper##msg_class;
 634
 635 #else
 636
 637 // Normal inclusion produces nothing extra.
 638 #define IPC_MESSAGE_EXTRA(sync, kind, msg_class,                \
 639                           in_cnt, out_cnt, in_list, out_list)
 640
 641 #endif // defined(IPC_MESSAGE_IMPL)
 642
 643 // Handle variable sized argument lists.  These are usually invoked by token
 644 // pasting against the argument counts.
 645 #define IPC_TYPE_IN_0()
 646 #define IPC_TYPE_IN_1(t1)                   const t1& arg1
 647 #define IPC_TYPE_IN_2(t1, t2)               const t1& arg1, const t2& arg2
 648 #define IPC_TYPE_IN_3(t1, t2, t3)           const t1& arg1, const t2& arg2, const t3& arg3
 649 #define IPC_TYPE_IN_4(t1, t2, t3, t4)       const t1& arg1, const t2& arg2, const t3& arg3, const t4& arg4
 650 #define IPC_TYPE_IN_5(t1, t2, t3, t4, t5)   const t1& arg1, const t2& arg2, const t3& arg3, const t4& arg4, const t5& arg5
 651 #define IPC_TYPE_IN_6(t1, t2, t3, t4, t5, t6)   const t1& arg1, const t2& arg2, const t3& arg3, const t4& arg4, const t5& arg5, const t6& arg6
 652
 653 #define IPC_TYPE_OUT_0()
 654 #define IPC_TYPE_OUT_1(t1)                  t1* arg7
 655 #define IPC_TYPE_OUT_2(t1, t2)              t1* arg7, t2* arg8
 656 #define IPC_TYPE_OUT_3(t1, t2, t3)          t1* arg7, t2* arg8, t3* arg9
 657 #define IPC_TYPE_OUT_4(t1, t2, t3, t4)      t1* arg7, t2* arg8, t3* arg9, t4* arg10
 658
 659 #define IPC_TUPLE_IN_0()                    Tuple0
 660 #define IPC_TUPLE_IN_1(t1)                  Tuple1<t1>
 661 #define IPC_TUPLE_IN_2(t1, t2)              Tuple2<t1, t2>
 662 #define IPC_TUPLE_IN_3(t1, t2, t3)          Tuple3<t1, t2, t3>
 663 #define IPC_TUPLE_IN_4(t1, t2, t3, t4)      Tuple4<t1, t2, t3, t4>
 664 #define IPC_TUPLE_IN_5(t1, t2, t3, t4, t5)  Tuple5<t1, t2, t3, t4, t5>
 665 #define IPC_TUPLE_IN_6(t1, t2, t3, t4, t5, t6)  Tuple6<t1, t2, t3, t4, t5, t6>
 666
 667 #define IPC_TUPLE_OUT_0()                   Tuple0
 668 #define IPC_TUPLE_OUT_1(t1)                 Tuple1<t1&>
 669 #define IPC_TUPLE_OUT_2(t1, t2)             Tuple2<t1&, t2&>
 670 #define IPC_TUPLE_OUT_3(t1, t2, t3)         Tuple3<t1&, t2&, t3&>
 671 #define IPC_TUPLE_OUT_4(t1, t2, t3, t4)     Tuple4<t1&, t2&, t3&, t4&>
 672
 673 #define IPC_NAME_IN_0()                     MakeTuple()
 674 #define IPC_NAME_IN_1(t1)                   MakeRefTuple(arg1)
 675 #define IPC_NAME_IN_2(t1, t2)               MakeRefTuple(arg1, arg2)
 676 #define IPC_NAME_IN_3(t1, t2, t3)           MakeRefTuple(arg1, arg2, arg3)
 677 #define IPC_NAME_IN_4(t1, t2, t3, t4)       MakeRefTuple(arg1, arg2, arg3, arg4)
 678 #define IPC_NAME_IN_5(t1, t2, t3, t4, t5)   MakeRefTuple(arg1, arg2, arg3, arg4, arg5)
 679 #define IPC_NAME_IN_6(t1, t2, t3, t4, t5, t6)   MakeRefTuple(arg1, arg2, arg3, arg4, arg5, arg6)
 680
 681 #define IPC_NAME_OUT_0()                    MakeTuple()
 682 #define IPC_NAME_OUT_1(t1)                  MakeRefTuple(*arg7)
 683 #define IPC_NAME_OUT_2(t1, t2)              MakeRefTuple(*arg7, *arg8)
 684 #define IPC_NAME_OUT_3(t1, t2, t3)          MakeRefTuple(*arg7, *arg8, *arg9)
 685 #define IPC_NAME_OUT_4(t1, t2, t3, t4)      MakeRefTuple(*arg7, *arg8, *arg9, *arg10)
 686
 687 // There are places where the syntax requires a comma if there are input args,
 688 // if there are input args and output args, or if there are input args or
 689 // output args.  These macros allow generation of the comma as needed; invoke
 690 // by token pasting against the argument counts.
 691 #define IPC_COMMA_0
 692 #define IPC_COMMA_1 ,
 693 #define IPC_COMMA_2 ,
 694 #define IPC_COMMA_3 ,
 695 #define IPC_COMMA_4 ,
 696 #define IPC_COMMA_5 ,
 697 #define IPC_COMMA_6 ,
 698
 699 #define IPC_COMMA_AND_0(x)
 700 #define IPC_COMMA_AND_1(x) x
 701 #define IPC_COMMA_AND_2(x) x
 702 #define IPC_COMMA_AND_3(x) x
 703 #define IPC_COMMA_AND_4(x) x
 704 #define IPC_COMMA_AND_5(x) x
 705 #define IPC_COMMA_AND_6(x) x
 706
 707 #define IPC_COMMA_OR_0(x) x
 708 #define IPC_COMMA_OR_1(x) ,
 709 #define IPC_COMMA_OR_2(x) ,
 710 #define IPC_COMMA_OR_3(x) ,
 711 #define IPC_COMMA_OR_4(x) ,
 712 #define IPC_COMMA_OR_5(x) ,
 713 #define IPC_COMMA_OR_6(x) ,
 714
 715 // Message IDs
 716 // Note: we currently use __LINE__ to give unique IDs to messages within
 717 // a file.  They're globally unique since each file defines its own
 718 // IPC_MESSAGE_START.  Ideally, we wouldn't use line numbers (a possibility
 719 // is to instead use the __COUNTER__ macro, but it needs gcc 4.3 and xcode
 720 // doesn't use it yet).
 721 #define IPC_MESSAGE_ID() ((IPC_MESSAGE_START << 16) + __LINE__)
 722 #define IPC_MESSAGE_ID_CLASS(id) ((id) >> 16)
 723 #define IPC_MESSAGE_ID_LINE(id) ((id) & 0xffff)
 724
 725 // Message crackers and handlers.
 726 // Prefer to use the IPC_BEGIN_MESSAGE_MAP_EX to the older macros since they
 727 // allow you to detect when a message could not be de-serialized. Usage:
 728 //
 729 //   bool MyClass::OnMessageReceived(const IPC::Message& msg) {
 730 //     bool handled = true;
 731 //     bool msg_is_good = false;
 732 //     IPC_BEGIN_MESSAGE_MAP_EX(MyClass, msg, msg_is_good)
 733 //       IPC_MESSAGE_HANDLER(MsgClassOne, OnMsgClassOne)
 734 //       ...more handlers here ...
 735 //       IPC_MESSAGE_HANDLER(MsgClassTen, OnMsgClassTen)
 736 //       IPC_MESSAGE_UNHANDLED(handled = false)
 737 //     IPC_END_MESSAGE_MAP_EX()
 738 //     if (!msg_is_good) {
 739 //       // Signal error here or terminate offending process.
 740 //     }
 741 //     return handled;
 742 //   }
 743
 744
 745 #define IPC_BEGIN_MESSAGE_MAP_EX(class_name, msg, msg_is_ok) \
 746   { \
 747     typedef class_name _IpcMessageHandlerClass; \
 748     const IPC::Message& ipc_message__ = msg; \
 749     bool& msg_is_ok__ = msg_is_ok; \
 750     switch (ipc_message__.type()) { \
 751
 752 #define IPC_BEGIN_MESSAGE_MAP(class_name, msg) \
 753   { \
 754     typedef class_name _IpcMessageHandlerClass; \
 755     const IPC::Message& ipc_message__ = msg; \
 756     bool msg_is_ok__ = true; \
 757     switch (ipc_message__.type()) { \
 758
 759 #define IPC_MESSAGE_FORWARD(msg_class, obj, member_func) \
 760   case msg_class::ID: \
 761     msg_is_ok__ = msg_class::Dispatch(&ipc_message__, obj, this, &member_func); \
 762     break;
 763
 764 #define IPC_MESSAGE_FORWARD_EX(msg_class, obj, sender, member_func)     \
 765   case msg_class::ID: \
 766   msg_is_ok__ = msg_class::Dispatch(&ipc_message__, obj, sender, &member_func); \
 767     break;
 768
 769 #define IPC_MESSAGE_HANDLER(msg_class, member_func, sender)                     \
 770     IPC_MESSAGE_FORWARD_EX(msg_class, this, sender, _IpcMessageHandlerClass::member_func)
 771
 772 #define IPC_MESSAGE_HANDLER_EX(msg_class, sender, member_func)                  \
 773     IPC_MESSAGE_FORWARD_EX(msg_class, this, sender, _IpcMessageHandlerClass::member_func)
 774
 775 #define IPC_MESSAGE_FORWARD_DELAY_REPLY(msg_class, obj, member_func) \
 776     case msg_class::ID: \
 777     msg_is_ok__ = msg_class::DispatchDelayReply(&ipc_message__, obj, &member_func); \
 778     break;
 779
 780 #define IPC_MESSAGE_HANDLER_DELAY_REPLY(msg_class, member_func) \
 781   IPC_MESSAGE_FORWARD_DELAY_REPLY(msg_class, this, \
 782                                   _IpcMessageHandlerClass::member_func)
 783
 784 #define IPC_MESSAGE_HANDLER_GENERIC(msg_class, code) \
 785   case msg_class::ID: \
 786     code; \
 787     break;
 788
 789 #define IPC_REPLY_HANDLER(func) \
 790    case IPC_REPLY_ID: \
 791      func(ipc_message__); \
 792      break;
 793
 794
 795 #define IPC_MESSAGE_UNHANDLED(code) \
 796   default: \
 797     code; \
 798     break;
 799
 800 #define IPC_MESSAGE_UNHANDLED_ERROR() \
 801   IPC_MESSAGE_UNHANDLED(NOTREACHED() << \
 802                               "Invalid message with type = " << \
 803                               ipc_message__.type())
 804
 805 #define IPC_END_MESSAGE_MAP() \
 806   } \
 807 }
 808
 809 #define IPC_END_MESSAGE_MAP_EX() \
 810   } \
 811 }
 812
 813 // This corresponds to an enum value from IPCMessageStart.
 814 #define IPC_MESSAGE_CLASS(message) \
 815   IPC_MESSAGE_ID_CLASS(message.type())
 816
 817 #endif  // IPC_IPC_MESSAGE_MACROS_H_
 818
 819 // Clean up IPC_MESSAGE_START in this unguarded section so that the
 820 // XXX_messages.h files need not do so themselves.  This makes the
 821 // XXX_messages.h files easier to write.
 822 #undef IPC_MESSAGE_START