gcc/gthr-posix.h

   1 /* Threads compatibility routines for libgcc2 and libobjc.  */
   2 /* Compile this one with gcc.  */
   3 /* Copyright (C) 1997, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
   4    Free Software Foundation, Inc.
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 2, or (at your option) any later
  11 version.
  12
  13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GCC; see the file COPYING.  If not, write to the Free
  20 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
  21 02110-1301, USA.  */
  22
  23 /* As a special exception, if you link this library with other files,
  24    some of which are compiled with GCC, to produce an executable,
  25    this library does not by itself cause the resulting executable
  26    to be covered by the GNU General Public License.
  27    This exception does not however invalidate any other reasons why
  28    the executable file might be covered by the GNU General Public License.  */
  29
  30 #ifndef GCC_GTHR_POSIX_H
  31 #define GCC_GTHR_POSIX_H
  32
  33 /* POSIX threads specific definitions.
  34    Easy, since the interface is just one-to-one mapping.  */
  35
  36 #define __GTHREADS 1
  37
  38 /* Some implementations of <pthread.h> require this to be defined.  */
  39 #ifndef _REENTRANT
  40 #define _REENTRANT 1
  41 #endif
  42
  43 #include <pthread.h>
  44 #include <unistd.h>
  45
  46 typedef pthread_key_t __gthread_key_t;
  47 typedef pthread_once_t __gthread_once_t;
  48 typedef pthread_mutex_t __gthread_mutex_t;
  49 typedef pthread_mutex_t __gthread_recursive_mutex_t;
  50
  51 #define __GTHREAD_MUTEX_INIT PTHREAD_MUTEX_INITIALIZER
  52 #define __GTHREAD_ONCE_INIT PTHREAD_ONCE_INIT
  53 #if defined(PTHREAD_RECURSIVE_MUTEX_INITIALIZER)
  54 #define __GTHREAD_RECURSIVE_MUTEX_INIT PTHREAD_RECURSIVE_MUTEX_INITIALIZER
  55 #elif defined(PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP)
  56 #define __GTHREAD_RECURSIVE_MUTEX_INIT PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP
  57 #else
  58 #define __GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION __gthread_recursive_mutex_init_function
  59 #endif
  60
  61 #if SUPPORTS_WEAK && GTHREAD_USE_WEAK
  62 # define __gthrw2(name,name2) \
  63   static __typeof(name) __gthrw_ ## name __attribute__ ((__weakref__(#name2)));
  64 # define __gthrw_(name) __gthrw_ ## name
  65 #else
  66 # define __gthrw2(name,name2)
  67 # define __gthrw_(name) name
  68 #endif
  69
  70 /* Typically, __gthrw_foo is a weak reference to symbol foo.  */
  71 #define __gthrw(name) __gthrw2(name,name)
  72
  73 /* On Tru64, /usr/include/pthread.h uses #pragma extern_prefix "__" to
  74    map a subset of the POSIX pthread API to mangled versions of their
  75    names.  */
  76 #if defined(__osf__) && defined(_PTHREAD_USE_MANGLED_NAMES_)
  77 __gthrw2(pthread_once,__pthread_once)
  78 __gthrw2(pthread_getspecific,__pthread_getspecific)
  79 __gthrw2(pthread_setspecific,__pthread_setspecific)
  80 __gthrw2(pthread_create,__pthread_create)
  81 __gthrw2(pthread_cancel,__pthread_cancel)
  82 __gthrw2(pthread_mutex_lock,__pthread_mutex_lock)
  83 __gthrw2(pthread_mutex_trylock,__pthread_mutex_trylock)
  84 __gthrw2(pthread_mutex_unlock,__pthread_mutex_unlock)
  85 __gthrw2(pthread_mutex_init,__pthread_mutex_init)
  86 #else
  87 __gthrw(pthread_once)
  88 __gthrw(pthread_getspecific)
  89 __gthrw(pthread_setspecific)
  90 __gthrw(pthread_create)
  91 __gthrw(pthread_cancel)
  92 __gthrw(pthread_mutex_lock)
  93 __gthrw(pthread_mutex_trylock)
  94 __gthrw(pthread_mutex_unlock)
  95 __gthrw(pthread_mutex_init)
  96 #endif
  97
  98 __gthrw(pthread_key_create)
  99 __gthrw(pthread_key_delete)
 100 __gthrw(pthread_mutexattr_init)
 101 __gthrw(pthread_mutexattr_settype)
 102 __gthrw(pthread_mutexattr_destroy)
 103
 104
 105 #if defined(_LIBOBJC) || defined(_LIBOBJC_WEAK)
 106 /* Objective-C.  */
 107 #if defined(__osf__) && defined(_PTHREAD_USE_MANGLED_NAMES_)
 108 __gthrw2(pthread_cond_broadcast,__pthread_cond_broadcast)
 109 __gthrw2(pthread_cond_destroy,__pthread_cond_destroy)
 110 __gthrw2(pthread_cond_init,__pthread_cond_init)
 111 __gthrw2(pthread_cond_signal,__pthread_cond_signal)
 112 __gthrw2(pthread_cond_wait,__pthread_cond_wait)
 113 __gthrw2(pthread_exit,__pthread_exit)
 114 __gthrw2(pthread_mutex_destroy,__pthread_mutex_destroy)
 115 __gthrw2(pthread_self,__pthread_self)
 116 #else
 117 __gthrw(pthread_cond_broadcast)
 118 __gthrw(pthread_cond_destroy)
 119 __gthrw(pthread_cond_init)
 120 __gthrw(pthread_cond_signal)
 121 __gthrw(pthread_cond_wait)
 122 __gthrw(pthread_exit)
 123 __gthrw(pthread_mutex_destroy)
 124 __gthrw(pthread_self)
 125 #endif /* __osf__ && _PTHREAD_USE_MANGLED_NAMES_ */
 126 #ifdef _POSIX_PRIORITY_SCHEDULING
 127 #ifdef _POSIX_THREAD_PRIORITY_SCHEDULING
 128 __gthrw(sched_get_priority_max)
 129 __gthrw(sched_get_priority_min)
 130 #endif /* _POSIX_THREAD_PRIORITY_SCHEDULING */
 131 #endif /* _POSIX_PRIORITY_SCHEDULING */
 132 __gthrw(sched_yield)
 133 __gthrw(pthread_attr_destroy)
 134 __gthrw(pthread_attr_init)
 135 __gthrw(pthread_attr_setdetachstate)
 136 #ifdef _POSIX_THREAD_PRIORITY_SCHEDULING
 137 __gthrw(pthread_getschedparam)
 138 __gthrw(pthread_setschedparam)
 139 #endif /* _POSIX_THREAD_PRIORITY_SCHEDULING */
 140 #endif /* _LIBOBJC || _LIBOBJC_WEAK */
 141
 142 #if SUPPORTS_WEAK && GTHREAD_USE_WEAK
 143
 144 static inline int
 145 __gthread_active_p (void)
 146 {
 147   static void *const __gthread_active_ptr
 148     = __extension__ (void *) &__gthrw_(pthread_cancel);
 149   return __gthread_active_ptr != 0;
 150 }
 151
 152 #else /* not SUPPORTS_WEAK */
 153
 154 static inline int
 155 __gthread_active_p (void)
 156 {
 157   return 1;
 158 }
 159
 160 #endif /* SUPPORTS_WEAK */
 161
 162 #ifdef _LIBOBJC
 163
 164 /* This is the config.h file in libobjc/ */
 165 #include <config.h>
 166
 167 #ifdef HAVE_SCHED_H
 168 # include <sched.h>
 169 #endif
 170
 171 /* Key structure for maintaining thread specific storage */
 172 static pthread_key_t _objc_thread_storage;
 173 static pthread_attr_t _objc_thread_attribs;
 174
 175 /* Thread local storage for a single thread */
 176 static void *thread_local_storage = NULL;
 177
 178 /* Backend initialization functions */
 179
 180 /* Initialize the threads subsystem.  */
 181 static inline int
 182 __gthread_objc_init_thread_system (void)
 183 {
 184   if (__gthread_active_p ())
 185     {
 186       /* Initialize the thread storage key.  */
 187       if (__gthrw_(pthread_key_create) (&_objc_thread_storage, NULL) == 0)
 188         {
 189           /* The normal default detach state for threads is
 190            * PTHREAD_CREATE_JOINABLE which causes threads to not die
 191            * when you think they should.  */
 192           if (__gthrw_(pthread_attr_init) (&_objc_thread_attribs) == 0
 193               && __gthrw_(pthread_attr_setdetachstate) (&_objc_thread_attribs,
 194                                               PTHREAD_CREATE_DETACHED) == 0)
 195             return 0;
 196         }
 197     }
 198
 199   return -1;
 200 }
 201
 202 /* Close the threads subsystem.  */
 203 static inline int
 204 __gthread_objc_close_thread_system (void)
 205 {
 206   if (__gthread_active_p ()
 207       && __gthrw_(pthread_key_delete) (_objc_thread_storage) == 0
 208       && __gthrw_(pthread_attr_destroy) (&_objc_thread_attribs) == 0)
 209     return 0;
 210
 211   return -1;
 212 }
 213
 214 /* Backend thread functions */
 215
 216 /* Create a new thread of execution.  */
 217 static inline objc_thread_t
 218 __gthread_objc_thread_detach (void (*func)(void *), void *arg)
 219 {
 220   objc_thread_t thread_id;
 221   pthread_t new_thread_handle;
 222
 223   if (!__gthread_active_p ())
 224     return NULL;
 225
 226   if (!(__gthrw_(pthread_create) (&new_thread_handle, NULL, (void *) func, arg)))
 227     thread_id = (objc_thread_t) new_thread_handle;
 228   else
 229     thread_id = NULL;
 230
 231   return thread_id;
 232 }
 233
 234 /* Set the current thread's priority.  */
 235 static inline int
 236 __gthread_objc_thread_set_priority (int priority)
 237 {
 238   if (!__gthread_active_p ())
 239     return -1;
 240   else
 241     {
 242 #ifdef _POSIX_PRIORITY_SCHEDULING
 243 #ifdef _POSIX_THREAD_PRIORITY_SCHEDULING
 244       pthread_t thread_id = __gthrw_(pthread_self) ();
 245       int policy;
 246       struct sched_param params;
 247       int priority_min, priority_max;
 248
 249       if (__gthrw_(pthread_getschedparam) (thread_id, &policy, &params) == 0)
 250         {
 251           if ((priority_max = __gthrw_(sched_get_priority_max) (policy)) == -1)
 252             return -1;
 253
 254           if ((priority_min = __gthrw_(sched_get_priority_min) (policy)) == -1)
 255             return -1;
 256
 257           if (priority > priority_max)
 258             priority = priority_max;
 259           else if (priority < priority_min)
 260             priority = priority_min;
 261           params.sched_priority = priority;
 262
 263           /*
 264            * The solaris 7 and several other man pages incorrectly state that
 265            * this should be a pointer to policy but pthread.h is universally
 266            * at odds with this.
 267            */
 268           if (__gthrw_(pthread_setschedparam) (thread_id, policy, &params) == 0)
 269             return 0;
 270         }
 271 #endif /* _POSIX_THREAD_PRIORITY_SCHEDULING */
 272 #endif /* _POSIX_PRIORITY_SCHEDULING */
 273       return -1;
 274     }
 275 }
 276
 277 /* Return the current thread's priority.  */
 278 static inline int
 279 __gthread_objc_thread_get_priority (void)
 280 {
 281 #ifdef _POSIX_PRIORITY_SCHEDULING
 282 #ifdef _POSIX_THREAD_PRIORITY_SCHEDULING
 283   if (__gthread_active_p ())
 284     {
 285       int policy;
 286       struct sched_param params;
 287
 288       if (__gthrw_(pthread_getschedparam) (__gthrw_(pthread_self) (), &policy, &params) == 0)
 289         return params.sched_priority;
 290       else
 291         return -1;
 292     }
 293   else
 294 #endif /* _POSIX_THREAD_PRIORITY_SCHEDULING */
 295 #endif /* _POSIX_PRIORITY_SCHEDULING */
 296     return OBJC_THREAD_INTERACTIVE_PRIORITY;
 297 }
 298
 299 /* Yield our process time to another thread.  */
 300 static inline void
 301 __gthread_objc_thread_yield (void)
 302 {
 303   if (__gthread_active_p ())
 304     __gthrw_(sched_yield) ();
 305 }
 306
 307 /* Terminate the current thread.  */
 308 static inline int
 309 __gthread_objc_thread_exit (void)
 310 {
 311   if (__gthread_active_p ())
 312     /* exit the thread */
 313     __gthrw_(pthread_exit) (&__objc_thread_exit_status);
 314
 315   /* Failed if we reached here */
 316   return -1;
 317 }
 318
 319 /* Returns an integer value which uniquely describes a thread.  */
 320 static inline objc_thread_t
 321 __gthread_objc_thread_id (void)
 322 {
 323   if (__gthread_active_p ())
 324     return (objc_thread_t) __gthrw_(pthread_self) ();
 325   else
 326     return (objc_thread_t) 1;
 327 }
 328
 329 /* Sets the thread's local storage pointer.  */
 330 static inline int
 331 __gthread_objc_thread_set_data (void *value)
 332 {
 333   if (__gthread_active_p ())
 334     return __gthrw_(pthread_setspecific) (_objc_thread_storage, value);
 335   else
 336     {
 337       thread_local_storage = value;
 338       return 0;
 339     }
 340 }
 341
 342 /* Returns the thread's local storage pointer.  */
 343 static inline void *
 344 __gthread_objc_thread_get_data (void)
 345 {
 346   if (__gthread_active_p ())
 347     return __gthrw_(pthread_getspecific) (_objc_thread_storage);
 348   else
 349     return thread_local_storage;
 350 }
 351
 352 /* Backend mutex functions */
 353
 354 /* Allocate a mutex.  */
 355 static inline int
 356 __gthread_objc_mutex_allocate (objc_mutex_t mutex)
 357 {
 358   if (__gthread_active_p ())
 359     {
 360       mutex->backend = objc_malloc (sizeof (pthread_mutex_t));
 361
 362       if (__gthrw_(pthread_mutex_init) ((pthread_mutex_t *) mutex->backend, NULL))
 363         {
 364           objc_free (mutex->backend);
 365           mutex->backend = NULL;
 366           return -1;
 367         }
 368     }
 369
 370   return 0;
 371 }
 372
 373 /* Deallocate a mutex.  */
 374 static inline int
 375 __gthread_objc_mutex_deallocate (objc_mutex_t mutex)
 376 {
 377   if (__gthread_active_p ())
 378     {
 379       int count;
 380
 381       /*
 382        * Posix Threads specifically require that the thread be unlocked
 383        * for __gthrw_(pthread_mutex_destroy) to work.
 384        */
 385
 386       do
 387         {
 388           count = __gthrw_(pthread_mutex_unlock) ((pthread_mutex_t *) mutex->backend);
 389           if (count < 0)
 390             return -1;
 391         }
 392       while (count);
 393
 394       if (__gthrw_(pthread_mutex_destroy) ((pthread_mutex_t *) mutex->backend))
 395         return -1;
 396
 397       objc_free (mutex->backend);
 398       mutex->backend = NULL;
 399     }
 400   return 0;
 401 }
 402
 403 /* Grab a lock on a mutex.  */
 404 static inline int
 405 __gthread_objc_mutex_lock (objc_mutex_t mutex)
 406 {
 407   if (__gthread_active_p ()
 408       && __gthrw_(pthread_mutex_lock) ((pthread_mutex_t *) mutex->backend) != 0)
 409     {
 410       return -1;
 411     }
 412
 413   return 0;
 414 }
 415
 416 /* Try to grab a lock on a mutex.  */
 417 static inline int
 418 __gthread_objc_mutex_trylock (objc_mutex_t mutex)
 419 {
 420   if (__gthread_active_p ()
 421       && __gthrw_(pthread_mutex_trylock) ((pthread_mutex_t *) mutex->backend) != 0)
 422     {
 423       return -1;
 424     }
 425
 426   return 0;
 427 }
 428
 429 /* Unlock the mutex */
 430 static inline int
 431 __gthread_objc_mutex_unlock (objc_mutex_t mutex)
 432 {
 433   if (__gthread_active_p ()
 434       && __gthrw_(pthread_mutex_unlock) ((pthread_mutex_t *) mutex->backend) != 0)
 435     {
 436       return -1;
 437     }
 438
 439   return 0;
 440 }
 441
 442 /* Backend condition mutex functions */
 443
 444 /* Allocate a condition.  */
 445 static inline int
 446 __gthread_objc_condition_allocate (objc_condition_t condition)
 447 {
 448   if (__gthread_active_p ())
 449     {
 450       condition->backend = objc_malloc (sizeof (pthread_cond_t));
 451
 452       if (__gthrw_(pthread_cond_init) ((pthread_cond_t *) condition->backend, NULL))
 453         {
 454           objc_free (condition->backend);
 455           condition->backend = NULL;
 456           return -1;
 457         }
 458     }
 459
 460   return 0;
 461 }
 462
 463 /* Deallocate a condition.  */
 464 static inline int
 465 __gthread_objc_condition_deallocate (objc_condition_t condition)
 466 {
 467   if (__gthread_active_p ())
 468     {
 469       if (__gthrw_(pthread_cond_destroy) ((pthread_cond_t *) condition->backend))
 470         return -1;
 471
 472       objc_free (condition->backend);
 473       condition->backend = NULL;
 474     }
 475   return 0;
 476 }
 477
 478 /* Wait on the condition */
 479 static inline int
 480 __gthread_objc_condition_wait (objc_condition_t condition, objc_mutex_t mutex)
 481 {
 482   if (__gthread_active_p ())
 483     return __gthrw_(pthread_cond_wait) ((pthread_cond_t *) condition->backend,
 484                               (pthread_mutex_t *) mutex->backend);
 485   else
 486     return 0;
 487 }
 488
 489 /* Wake up all threads waiting on this condition.  */
 490 static inline int
 491 __gthread_objc_condition_broadcast (objc_condition_t condition)
 492 {
 493   if (__gthread_active_p ())
 494     return __gthrw_(pthread_cond_broadcast) ((pthread_cond_t *) condition->backend);
 495   else
 496     return 0;
 497 }
 498
 499 /* Wake up one thread waiting on this condition.  */
 500 static inline int
 501 __gthread_objc_condition_signal (objc_condition_t condition)
 502 {
 503   if (__gthread_active_p ())
 504     return __gthrw_(pthread_cond_signal) ((pthread_cond_t *) condition->backend);
 505   else
 506     return 0;
 507 }
 508
 509 #else /* _LIBOBJC */
 510
 511 static inline int
 512 __gthread_once (__gthread_once_t *once, void (*func) (void))
 513 {
 514   if (__gthread_active_p ())
 515     return __gthrw_(pthread_once) (once, func);
 516   else
 517     return -1;
 518 }
 519
 520 static inline int
 521 __gthread_key_create (__gthread_key_t *key, void (*dtor) (void *))
 522 {
 523   return __gthrw_(pthread_key_create) (key, dtor);
 524 }
 525
 526 static inline int
 527 __gthread_key_delete (__gthread_key_t key)
 528 {
 529   return __gthrw_(pthread_key_delete) (key);
 530 }
 531
 532 static inline void *
 533 __gthread_getspecific (__gthread_key_t key)
 534 {
 535   return __gthrw_(pthread_getspecific) (key);
 536 }
 537
 538 static inline int
 539 __gthread_setspecific (__gthread_key_t key, const void *ptr)
 540 {
 541   return __gthrw_(pthread_setspecific) (key, ptr);
 542 }
 543
 544 static inline int
 545 __gthread_mutex_lock (__gthread_mutex_t *mutex)
 546 {
 547   if (__gthread_active_p ())
 548     return __gthrw_(pthread_mutex_lock) (mutex);
 549   else
 550     return 0;
 551 }
 552
 553 static inline int
 554 __gthread_mutex_trylock (__gthread_mutex_t *mutex)
 555 {
 556   if (__gthread_active_p ())
 557     return __gthrw_(pthread_mutex_trylock) (mutex);
 558   else
 559     return 0;
 560 }
 561
 562 static inline int
 563 __gthread_mutex_unlock (__gthread_mutex_t *mutex)
 564 {
 565   if (__gthread_active_p ())
 566     return __gthrw_(pthread_mutex_unlock) (mutex);
 567   else
 568     return 0;
 569 }
 570
 571 #ifndef PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP
 572 static inline int
 573 __gthread_recursive_mutex_init_function (__gthread_recursive_mutex_t *mutex)
 574 {
 575   if (__gthread_active_p ())
 576     {
 577       pthread_mutexattr_t attr;
 578       int r;
 579
 580       r = __gthrw_(pthread_mutexattr_init) (&attr);
 581       if (!r)
 582         r = __gthrw_(pthread_mutexattr_settype) (&attr, PTHREAD_MUTEX_RECURSIVE);
 583       if (!r)
 584         r = __gthrw_(pthread_mutex_init) (mutex, &attr);
 585       if (!r)
 586         r = __gthrw_(pthread_mutexattr_destroy) (&attr);
 587       return r;
 588     }
 589   return 0;
 590 }
 591 #endif
 592
 593 static inline int
 594 __gthread_recursive_mutex_lock (__gthread_recursive_mutex_t *mutex)
 595 {
 596   return __gthread_mutex_lock (mutex);
 597 }
 598
 599 static inline int
 600 __gthread_recursive_mutex_trylock (__gthread_recursive_mutex_t *mutex)
 601 {
 602   return __gthread_mutex_trylock (mutex);
 603 }
 604
 605 static inline int
 606 __gthread_recursive_mutex_unlock (__gthread_recursive_mutex_t *mutex)
 607 {
 608   return __gthread_mutex_unlock (mutex);
 609 }
 610
 611 #endif /* _LIBOBJC */
 612
 613 #endif /* ! GCC_GTHR_POSIX_H */