libcc1/rpc.hh

   1 /* RPC call and callback templates
   2    Copyright (C) 2014-2020 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify it under
   7 the terms of the GNU General Public License as published by the Free
   8 Software Foundation; either version 3, or (at your option) any later
   9 version.
  10
  11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14 for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GCC; see the file COPYING3.  If not see
  18 <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef CC1_PLUGIN_RPC_HH
  21 #define CC1_PLUGIN_RPC_HH
  22
  23 #include "status.hh"
  24 #include "connection.hh"
  25
  26 namespace cc1_plugin
  27 {
  28   // The plugin API may contain some "const" method parameters.
  29   // However, when unmarshalling we cannot unmarshall into a const
  30   // object; and furthermore we want to be able to deallocate pointers
  31   // when finished with them.  This wrapper class lets us properly
  32   // remove the "const" and handle deallocation from pointer types.
  33
  34   template<typename T>
  35   class argument_wrapper
  36   {
  37   public:
  38
  39     argument_wrapper () { }
  40     ~argument_wrapper () { }
  41
  42     operator T () const { return m_object; }
  43
  44     status unmarshall (connection *conn)
  45     {
  46       return ::cc1_plugin::unmarshall (conn, &m_object);
  47     }
  48
  49   private:
  50
  51     T m_object;
  52
  53     // No copying or assignment allowed.
  54     argument_wrapper (const argument_wrapper &);
  55     argument_wrapper &operator= (const argument_wrapper &);
  56   };
  57
  58   // Specialization for any kind of pointer.  This is declared but not
  59   // defined to avoid bugs if a new pointer type is introduced into
  60   // the API.  Instead you will just get a compilation error.
  61   template<typename T>
  62   class argument_wrapper<const T *>;
  63
  64   // Specialization for string types.
  65   template<>
  66   class argument_wrapper<const char *>
  67   {
  68   public:
  69     argument_wrapper () : m_object (NULL) { }
  70     ~argument_wrapper ()
  71     {
  72       delete[] m_object;
  73     }
  74
  75     operator const char * () const
  76     {
  77       return m_object;
  78     }
  79
  80     status unmarshall (connection *conn)
  81     {
  82       return ::cc1_plugin::unmarshall (conn, &m_object);
  83     }
  84
  85   private:
  86
  87     char *m_object;
  88
  89     // No copying or assignment allowed.
  90     argument_wrapper (const argument_wrapper &);
  91     argument_wrapper &operator= (const argument_wrapper &);
  92   };
  93
  94   // Specialization for gcc_type_array.
  95   template<>
  96   class argument_wrapper<const gcc_type_array *>
  97   {
  98   public:
  99     argument_wrapper () : m_object (NULL) { }
 100     ~argument_wrapper ()
 101     {
 102       // It would be nicer if gcc_type_array could have a destructor.
 103       // But, it is in code shared with gdb and cannot.
 104       if (m_object != NULL)
 105         delete[] m_object->elements;
 106       delete m_object;
 107     }
 108
 109     operator const gcc_type_array * () const
 110     {
 111       return m_object;
 112     }
 113
 114     status unmarshall (connection *conn)
 115     {
 116       return ::cc1_plugin::unmarshall (conn, &m_object);
 117     }
 118
 119   private:
 120
 121     gcc_type_array *m_object;
 122
 123     // No copying or assignment allowed.
 124     argument_wrapper (const argument_wrapper &);
 125     argument_wrapper &operator= (const argument_wrapper &);
 126   };
 127
 128 #ifdef GCC_CP_INTERFACE_H
 129   // Specialization for gcc_vbase_array.
 130   template<>
 131   class argument_wrapper<const gcc_vbase_array *>
 132   {
 133   public:
 134     argument_wrapper () : m_object (NULL) { }
 135     ~argument_wrapper ()
 136     {
 137       // It would be nicer if gcc_type_array could have a destructor.
 138       // But, it is in code shared with gdb and cannot.
 139       if (m_object != NULL)
 140         {
 141           delete[] m_object->flags;
 142           delete[] m_object->elements;
 143         }
 144       delete m_object;
 145     }
 146
 147     operator const gcc_vbase_array * () const
 148     {
 149       return m_object;
 150     }
 151
 152     status unmarshall (connection *conn)
 153     {
 154       return ::cc1_plugin::unmarshall (conn, &m_object);
 155     }
 156
 157   private:
 158
 159     gcc_vbase_array *m_object;
 160
 161     // No copying or assignment allowed.
 162     argument_wrapper (const argument_wrapper &);
 163     argument_wrapper &operator= (const argument_wrapper &);
 164   };
 165
 166   // Specialization for gcc_cp_template_args.
 167   template<>
 168   class argument_wrapper<const gcc_cp_template_args *>
 169   {
 170   public:
 171     argument_wrapper () : m_object (NULL) { }
 172     ~argument_wrapper ()
 173     {
 174       // It would be nicer if gcc_type_array could have a destructor.
 175       // But, it is in code shared with gdb and cannot.
 176       if (m_object != NULL)
 177         {
 178           delete[] m_object->elements;
 179           delete[] m_object->kinds;
 180         }
 181       delete m_object;
 182     }
 183
 184     operator const gcc_cp_template_args * () const
 185     {
 186       return m_object;
 187     }
 188
 189     status unmarshall (connection *conn)
 190     {
 191       return ::cc1_plugin::unmarshall (conn, &m_object);
 192     }
 193
 194   private:
 195
 196     gcc_cp_template_args *m_object;
 197
 198     // No copying or assignment allowed.
 199     argument_wrapper (const argument_wrapper &);
 200     argument_wrapper &operator= (const argument_wrapper &);
 201   };
 202
 203   // Specialization for gcc_cp_function_args.
 204   template<>
 205   class argument_wrapper<const gcc_cp_function_args *>
 206   {
 207   public:
 208     argument_wrapper () : m_object (NULL) { }
 209     ~argument_wrapper ()
 210     {
 211       // It would be nicer if gcc_type_array could have a destructor.
 212       // But, it is in code shared with gdb and cannot.
 213       if (m_object != NULL)
 214         {
 215           delete[] m_object->elements;
 216         }
 217       delete m_object;
 218     }
 219
 220     operator const gcc_cp_function_args * () const
 221     {
 222       return m_object;
 223     }
 224
 225     status unmarshall (connection *conn)
 226     {
 227       return ::cc1_plugin::unmarshall (conn, &m_object);
 228     }
 229
 230   private:
 231
 232     gcc_cp_function_args *m_object;
 233
 234     // No copying or assignment allowed.
 235     argument_wrapper (const argument_wrapper &);
 236     argument_wrapper &operator= (const argument_wrapper &);
 237   };
 238 #endif /* GCC_CP_INTERFACE_H */
 239
 240   // There are two kinds of template functions here: "call" and
 241   // "callback".  They are each repeated multiple times to handle
 242   // different numbers of arguments.  (This would be improved with
 243   // C++11, though applying a call is still tricky until C++14 can be
 244   // used.)
 245
 246   // The "call" template is used for making a remote procedure call.
 247   // It starts a query ('Q') packet, marshalls its arguments, waits
 248   // for a result, and finally reads and returns the result via an
 249   // "out" parameter.
 250
 251   // The "callback" template is used when receiving a remote procedure
 252   // call.  This template function is suitable for use with the
 253   // "callbacks" and "connection" classes.  It decodes incoming
 254   // arguments, passes them to the wrapped function, and finally
 255   // marshalls a reply packet.
 256
 257   template<typename R>
 258   status
 259   call (connection *conn, const char *method, R *result)
 260   {
 261     if (!conn->send ('Q'))
 262       return FAIL;
 263     if (!marshall (conn, method))
 264       return FAIL;
 265     if (!marshall (conn, 0))
 266       return FAIL;
 267     if (!conn->wait_for_result ())
 268       return FAIL;
 269     if (!unmarshall (conn, result))
 270       return FAIL;
 271     return OK;
 272   }
 273
 274   template<typename R, R (*func) (connection *)>
 275   status
 276   callback (connection *conn)
 277   {
 278     R result;
 279
 280     if (!unmarshall_check (conn, 0))
 281       return FAIL;
 282     result = func (conn);
 283     if (!conn->send ('R'))
 284       return FAIL;
 285     return marshall (conn, result);
 286   }
 287
 288   template<typename R, typename A>
 289   status
 290   call (connection *conn, const char *method, R *result, A arg)
 291   {
 292     if (!conn->send ('Q'))
 293       return FAIL;
 294     if (!marshall (conn, method))
 295       return FAIL;
 296     if (!marshall (conn, 1))
 297       return FAIL;
 298     if (!marshall (conn, arg))
 299       return FAIL;
 300     if (!conn->wait_for_result ())
 301       return FAIL;
 302     if (!unmarshall (conn, result))
 303       return FAIL;
 304     return OK;
 305   }
 306
 307   template<typename R, typename A, R (*func) (connection *, A)>
 308   status
 309   callback (connection *conn)
 310   {
 311     argument_wrapper<A> arg;
 312     R result;
 313
 314     if (!unmarshall_check (conn, 1))
 315       return FAIL;
 316     if (!arg.unmarshall (conn))
 317       return FAIL;
 318     result = func (conn, arg);
 319     if (!conn->send ('R'))
 320       return FAIL;
 321     return marshall (conn, result);
 322   }
 323
 324   template<typename R, typename A1, typename A2>
 325   status
 326   call (connection *conn, const char *method, R *result, A1 arg1, A2 arg2)
 327   {
 328     if (!conn->send ('Q'))
 329       return FAIL;
 330     if (!marshall (conn, method))
 331       return FAIL;
 332     if (!marshall (conn, 2))
 333       return FAIL;
 334     if (!marshall (conn, arg1))
 335       return FAIL;
 336     if (!marshall (conn, arg2))
 337       return FAIL;
 338     if (!conn->wait_for_result ())
 339       return FAIL;
 340     if (!unmarshall (conn, result))
 341       return FAIL;
 342     return OK;
 343   }
 344
 345   template<typename R, typename A1, typename A2, R (*func) (connection *,
 346                                                             A1, A2)>
 347   status
 348   callback (connection *conn)
 349   {
 350     argument_wrapper<A1> arg1;
 351     argument_wrapper<A2> arg2;
 352     R result;
 353
 354     if (!unmarshall_check (conn, 2))
 355       return FAIL;
 356     if (!arg1.unmarshall (conn))
 357       return FAIL;
 358     if (!arg2.unmarshall (conn))
 359       return FAIL;
 360     result = func (conn, arg1, arg2);
 361     if (!conn->send ('R'))
 362       return FAIL;
 363     return marshall (conn, result);
 364   }
 365
 366   template<typename R, typename A1, typename A2, typename A3>
 367   status
 368   call (connection *conn, const char *method, R *result, A1 arg1, A2 arg2,
 369         A3 arg3)
 370   {
 371     if (!conn->send ('Q'))
 372       return FAIL;
 373     if (!marshall (conn, method))
 374       return FAIL;
 375     if (!marshall (conn, 3))
 376       return FAIL;
 377     if (!marshall (conn, arg1))
 378       return FAIL;
 379     if (!marshall (conn, arg2))
 380       return FAIL;
 381     if (!marshall (conn, arg3))
 382       return FAIL;
 383     if (!conn->wait_for_result ())
 384       return FAIL;
 385     if (!unmarshall (conn, result))
 386       return FAIL;
 387     return OK;
 388   }
 389
 390   template<typename R, typename A1, typename A2, typename A3,
 391            R (*func) (connection *, A1, A2, A3)>
 392   status
 393   callback (connection *conn)
 394   {
 395     argument_wrapper<A1> arg1;
 396     argument_wrapper<A2> arg2;
 397     argument_wrapper<A3> arg3;
 398     R result;
 399
 400     if (!unmarshall_check (conn, 3))
 401       return FAIL;
 402     if (!arg1.unmarshall (conn))
 403       return FAIL;
 404     if (!arg2.unmarshall (conn))
 405       return FAIL;
 406     if (!arg3.unmarshall (conn))
 407       return FAIL;
 408     result = func (conn, arg1, arg2, arg3);
 409     if (!conn->send ('R'))
 410       return FAIL;
 411     return marshall (conn, result);
 412   }
 413
 414   template<typename R, typename A1, typename A2, typename A3, typename A4>
 415   status
 416   call (connection *conn, const char *method, R *result, A1 arg1, A2 arg2,
 417         A3 arg3, A4 arg4)
 418   {
 419     if (!conn->send ('Q'))
 420       return FAIL;
 421     if (!marshall (conn, method))
 422       return FAIL;
 423     if (!marshall (conn, 4))
 424       return FAIL;
 425     if (!marshall (conn, arg1))
 426       return FAIL;
 427     if (!marshall (conn, arg2))
 428       return FAIL;
 429     if (!marshall (conn, arg3))
 430       return FAIL;
 431     if (!marshall (conn, arg4))
 432       return FAIL;
 433     if (!conn->wait_for_result ())
 434       return FAIL;
 435     if (!unmarshall (conn, result))
 436       return FAIL;
 437     return OK;
 438   }
 439
 440   template<typename R, typename A1, typename A2, typename A3, typename A4,
 441            R (*func) (connection *, A1, A2, A3, A4)>
 442   status
 443   callback (connection *conn)
 444   {
 445     argument_wrapper<A1> arg1;
 446     argument_wrapper<A2> arg2;
 447     argument_wrapper<A3> arg3;
 448     argument_wrapper<A4> arg4;
 449     R result;
 450
 451     if (!unmarshall_check (conn, 4))
 452       return FAIL;
 453     if (!arg1.unmarshall (conn))
 454       return FAIL;
 455     if (!arg2.unmarshall (conn))
 456       return FAIL;
 457     if (!arg3.unmarshall (conn))
 458       return FAIL;
 459     if (!arg4.unmarshall (conn))
 460       return FAIL;
 461     result = func (conn, arg1, arg2, arg3, arg4);
 462     if (!conn->send ('R'))
 463       return FAIL;
 464     return marshall (conn, result);
 465   }
 466
 467   template<typename R, typename A1, typename A2, typename A3, typename A4,
 468            typename A5>
 469   status
 470   call (connection *conn, const char *method, R *result, A1 arg1, A2 arg2,
 471         A3 arg3, A4 arg4, A5 arg5)
 472   {
 473     if (!conn->send ('Q'))
 474       return FAIL;
 475     if (!marshall (conn, method))
 476       return FAIL;
 477     if (!marshall (conn, 5))
 478       return FAIL;
 479     if (!marshall (conn, arg1))
 480       return FAIL;
 481     if (!marshall (conn, arg2))
 482       return FAIL;
 483     if (!marshall (conn, arg3))
 484       return FAIL;
 485     if (!marshall (conn, arg4))
 486       return FAIL;
 487     if (!marshall (conn, arg5))
 488       return FAIL;
 489     if (!conn->wait_for_result ())
 490       return FAIL;
 491     if (!unmarshall (conn, result))
 492       return FAIL;
 493     return OK;
 494   }
 495
 496   template<typename R, typename A1, typename A2, typename A3, typename A4,
 497            typename A5, R (*func) (connection *, A1, A2, A3, A4, A5)>
 498   status
 499   callback (connection *conn)
 500   {
 501     argument_wrapper<A1> arg1;
 502     argument_wrapper<A2> arg2;
 503     argument_wrapper<A3> arg3;
 504     argument_wrapper<A4> arg4;
 505     argument_wrapper<A5> arg5;
 506     R result;
 507
 508     if (!unmarshall_check (conn, 5))
 509       return FAIL;
 510     if (!arg1.unmarshall (conn))
 511       return FAIL;
 512     if (!arg2.unmarshall (conn))
 513       return FAIL;
 514     if (!arg3.unmarshall (conn))
 515       return FAIL;
 516     if (!arg4.unmarshall (conn))
 517       return FAIL;
 518     if (!arg5.unmarshall (conn))
 519       return FAIL;
 520     result = func (conn, arg1, arg2, arg3, arg4, arg5);
 521     if (!conn->send ('R'))
 522       return FAIL;
 523     return marshall (conn, result);
 524   }
 525
 526   template<typename R, typename A1, typename A2, typename A3, typename A4,
 527            typename A5, typename A6, typename A7>
 528   status
 529   call (connection *conn, const char *method, R *result, A1 arg1, A2 arg2,
 530         A3 arg3, A4 arg4, A5 arg5, A6 arg6, A7 arg7)
 531   {
 532     if (!conn->send ('Q'))
 533       return FAIL;
 534     if (!marshall (conn, method))
 535       return FAIL;
 536     if (!marshall (conn, 7))
 537       return FAIL;
 538     if (!marshall (conn, arg1))
 539       return FAIL;
 540     if (!marshall (conn, arg2))
 541       return FAIL;
 542     if (!marshall (conn, arg3))
 543       return FAIL;
 544     if (!marshall (conn, arg4))
 545       return FAIL;
 546     if (!marshall (conn, arg5))
 547       return FAIL;
 548     if (!marshall (conn, arg6))
 549       return FAIL;
 550     if (!marshall (conn, arg7))
 551       return FAIL;
 552     if (!conn->wait_for_result ())
 553       return FAIL;
 554     if (!unmarshall (conn, result))
 555       return FAIL;
 556     return OK;
 557   }
 558
 559   template<typename R, typename A1, typename A2, typename A3, typename A4,
 560            typename A5, typename A6, typename A7,
 561            R (*func) (connection *, A1, A2, A3, A4, A5, A6, A7)>
 562   status
 563   callback (connection *conn)
 564   {
 565     argument_wrapper<A1> arg1;
 566     argument_wrapper<A2> arg2;
 567     argument_wrapper<A3> arg3;
 568     argument_wrapper<A4> arg4;
 569     argument_wrapper<A5> arg5;
 570     argument_wrapper<A6> arg6;
 571     argument_wrapper<A7> arg7;
 572     R result;
 573
 574     if (!unmarshall_check (conn, 7))
 575       return FAIL;
 576     if (!arg1.unmarshall (conn))
 577       return FAIL;
 578     if (!arg2.unmarshall (conn))
 579       return FAIL;
 580     if (!arg3.unmarshall (conn))
 581       return FAIL;
 582     if (!arg4.unmarshall (conn))
 583       return FAIL;
 584     if (!arg5.unmarshall (conn))
 585       return FAIL;
 586     if (!arg6.unmarshall (conn))
 587       return FAIL;
 588     if (!arg7.unmarshall (conn))
 589       return FAIL;
 590     result = func (conn, arg1, arg2, arg3, arg4, arg5, arg6, arg7);
 591     if (!conn->send ('R'))
 592       return FAIL;
 593     return marshall (conn, result);
 594   }
 595 };
 596
 597 #endif // CC1_PLUGIN_RPC_HH