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 Free Software Foundation, Inc.
   4
   5 This file is part of GNU CC.
   6
   7 GNU CC is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2, or (at your option)
  10 any later version.
  11
  12 GNU CC is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GNU CC; see the file COPYING.  If not, write to
  19 the Free Software Foundation, 59 Temple Place - Suite 330,
  20 Boston, MA 02111-1307, USA.  */
  21
  22 /* As a special exception, if you link this library with other files,
  23    some of which are compiled with GCC, to produce an executable,
  24    this library does not by itself cause the resulting executable
  25    to be covered by the GNU General Public License.
  26    This exception does not however invalidate any other reasons why
  27    the executable file might be covered by the GNU General Public License.  */
  28
  29 #ifndef __gthr_posix_h
  30 #define __gthr_posix_h
  31
  32 /* POSIX threads specific definitions.
  33    Easy, since the interface is just one-to-one mapping. */
  34
  35 #define __GTHREADS 1
  36
  37 #include <pthread.h>
  38
  39 typedef pthread_key_t __gthread_key_t;
  40 typedef pthread_once_t __gthread_once_t;
  41 typedef pthread_mutex_t __gthread_mutex_t;
  42
  43 #define __GTHREAD_MUTEX_INIT PTHREAD_MUTEX_INITIALIZER
  44 #define __GTHREAD_ONCE_INIT PTHREAD_ONCE_INIT
  45
  46 #if SUPPORTS_WEAK && GTHREAD_USE_WEAK
  47
  48 #pragma weak pthread_once
  49 #pragma weak pthread_key_create
  50 #pragma weak pthread_key_delete
  51 #pragma weak pthread_getspecific
  52 #pragma weak pthread_setspecific
  53 #pragma weak pthread_create
  54
  55 #pragma weak pthread_mutex_lock
  56 #pragma weak pthread_mutex_trylock
  57 #pragma weak pthread_mutex_unlock
  58
  59 #ifdef _LIBOBJC
  60 /* Objective C. */
  61 #pragma weak pthread_cond_broadcast
  62 #pragma weak pthread_cond_destroy
  63 #pragma weak pthread_cond_init
  64 #pragma weak pthread_cond_signal
  65 #pragma weak pthread_cond_wait
  66 #pragma weak pthread_exit
  67 #pragma weak pthread_mutex_init
  68 #pragma weak pthread_mutex_destroy
  69 #pragma weak pthread_self
  70 #pragma weak sched_yield
  71 #pragma weak pthread_attr_destroy
  72 #pragma weak pthread_attr_init
  73 #pragma weak pthread_attr_setdetachstate
  74 #pragma weak pthread_getschedparam
  75 #pragma weak pthread_setschedparam
  76 #endif
  77
  78 static void *__gthread_active_ptr = (void *) &pthread_create;
  79
  80 static inline int
  81 __gthread_active_p (void)
  82 {
  83   return __gthread_active_ptr != 0;
  84 }
  85
  86 #else /* not SUPPORTS_WEAK */
  87
  88 static inline int
  89 __gthread_active_p (void)
  90 {
  91   return 1;
  92 }
  93
  94 #endif /* SUPPORTS_WEAK */
  95
  96 #ifdef _LIBOBJC
  97
  98 /* This is the config.h file in libobjc/ */
  99 #include <config.h>
 100
 101 #ifdef HAVE_SCHED_H
 102 # include <sched.h>
 103 #endif
 104
 105 /* Key structure for maintaining thread specific storage */
 106 static pthread_key_t _objc_thread_storage;
 107 static pthread_attr_t _objc_thread_attribs;
 108
 109 /* Thread local storage for a single thread */
 110 static void *thread_local_storage = NULL;
 111
 112 /* Backend initialization functions */
 113
 114 /* Initialize the threads subsystem. */
 115 static inline int
 116 __gthread_objc_init_thread_system(void)
 117 {
 118   if (__gthread_active_p ())
 119     {
 120       /* Initialize the thread storage key */
 121       if (pthread_key_create(&_objc_thread_storage, NULL) == 0)
 122         {
 123           /* The normal default detach state for threads is
 124            * PTHREAD_CREATE_JOINABLE which causes threads to not die
 125            * when you think they should.  */
 126           if (pthread_attr_init(&_objc_thread_attribs) == 0
 127               && pthread_attr_setdetachstate(&_objc_thread_attribs,
 128                                              PTHREAD_CREATE_DETACHED) == 0)
 129             return 0;
 130         }
 131     }
 132
 133   return -1;
 134 }
 135
 136 /* Close the threads subsystem. */
 137 static inline int
 138 __gthread_objc_close_thread_system(void)
 139 {
 140   if (__gthread_active_p ()
 141       && pthread_key_delete(_objc_thread_storage) == 0
 142       && pthread_attr_destroy(&_objc_thread_attribs) == 0)
 143     return 0;
 144
 145   return -1;
 146 }
 147
 148 /* Backend thread functions */
 149
 150 /* Create a new thread of execution. */
 151 static inline objc_thread_t
 152 __gthread_objc_thread_detach(void (*func)(void *), void *arg)
 153 {
 154   objc_thread_t thread_id;
 155   pthread_t new_thread_handle;
 156
 157   if (!__gthread_active_p ())
 158     return NULL;
 159
 160   if ( !(pthread_create(&new_thread_handle, NULL, (void *)func, arg)) )
 161     thread_id = (objc_thread_t) new_thread_handle;
 162   else
 163     thread_id = NULL;
 164
 165   return thread_id;
 166 }
 167
 168 /* Set the current thread's priority. */
 169 static inline int
 170 __gthread_objc_thread_set_priority(int priority)
 171 {
 172   if (!__gthread_active_p())
 173     return -1;
 174   else {
 175     pthread_t thread_id = pthread_self();
 176     int policy;
 177     struct sched_param params;
 178     int priority_min, priority_max;
 179
 180     if (pthread_getschedparam(thread_id, &policy, &params) == 0)
 181       {
 182         if ((priority_max = sched_get_priority_max(policy)) != 0)
 183           return -1;
 184
 185         if ((priority_min = sched_get_priority_min(policy)) != 0)
 186           return -1;
 187
 188         if (priority > priority_max)
 189           priority = priority_max;
 190         else if (priority < priority_min)
 191           priority = priority_min;
 192         params.sched_priority = priority;
 193
 194         /*
 195          * The solaris 7 and several other man pages incorrectly state that
 196          * this should be a pointer to policy but pthread.h is universally
 197          * at odds with this.
 198          */
 199         if (pthread_setschedparam(thread_id, policy, &params) == 0)
 200           return 0;
 201       }
 202     return -1;
 203   }
 204 }
 205
 206 /* Return the current thread's priority. */
 207 static inline int
 208 __gthread_objc_thread_get_priority(void)
 209 {
 210   if (__gthread_active_p ())
 211     {
 212       int policy;
 213       struct sched_param params;
 214
 215       if (pthread_getschedparam(pthread_self(), &policy, &params) == 0)
 216         return params.sched_priority;
 217       else
 218         return -1;
 219     }
 220   else
 221     return OBJC_THREAD_INTERACTIVE_PRIORITY;
 222 }
 223
 224 /* Yield our process time to another thread. */
 225 static inline void
 226 __gthread_objc_thread_yield(void)
 227 {
 228   if (__gthread_active_p ())
 229     sched_yield();
 230 }
 231
 232 /* Terminate the current thread. */
 233 static inline int
 234 __gthread_objc_thread_exit(void)
 235 {
 236   if (__gthread_active_p ())
 237     /* exit the thread */
 238     pthread_exit(&__objc_thread_exit_status);
 239
 240   /* Failed if we reached here */
 241   return -1;
 242 }
 243
 244 /* Returns an integer value which uniquely describes a thread. */
 245 static inline objc_thread_t
 246 __gthread_objc_thread_id(void)
 247 {
 248   if (__gthread_active_p ())
 249     return (objc_thread_t) pthread_self();
 250   else
 251     return (objc_thread_t) 1;
 252 }
 253
 254 /* Sets the thread's local storage pointer. */
 255 static inline int
 256 __gthread_objc_thread_set_data(void *value)
 257 {
 258   if (__gthread_active_p ())
 259     return pthread_setspecific(_objc_thread_storage, value);
 260   else
 261     {
 262       thread_local_storage = value;
 263       return 0;
 264     }
 265 }
 266
 267 /* Returns the thread's local storage pointer. */
 268 static inline void *
 269 __gthread_objc_thread_get_data(void)
 270 {
 271   if (__gthread_active_p ())
 272     return pthread_getspecific(_objc_thread_storage);
 273   else
 274     return thread_local_storage;
 275 }
 276
 277 /* Backend mutex functions */
 278
 279 /* Allocate a mutex. */
 280 static inline int
 281 __gthread_objc_mutex_allocate(objc_mutex_t mutex)
 282 {
 283   if (__gthread_active_p ())
 284     {
 285       mutex->backend = objc_malloc(sizeof(pthread_mutex_t));
 286
 287       if (pthread_mutex_init((pthread_mutex_t *)mutex->backend, NULL))
 288         {
 289           objc_free(mutex->backend);
 290           mutex->backend = NULL;
 291           return -1;
 292         }
 293     }
 294
 295   return 0;
 296 }
 297
 298 /* Deallocate a mutex. */
 299 static inline int
 300 __gthread_objc_mutex_deallocate(objc_mutex_t mutex)
 301 {
 302   if (__gthread_active_p ())
 303     {
 304       int count;
 305
 306       /*
 307        * Posix Threads specifically require that the thread be unlocked
 308        * for pthread_mutex_destroy to work.
 309        */
 310
 311       do
 312         {
 313           count = pthread_mutex_unlock((pthread_mutex_t *)mutex->backend);
 314           if (count < 0)
 315             return -1;
 316         }
 317       while (count);
 318
 319       if (pthread_mutex_destroy((pthread_mutex_t *)mutex->backend))
 320         return -1;
 321
 322       objc_free(mutex->backend);
 323       mutex->backend = NULL;
 324     }
 325   return 0;
 326 }
 327
 328 /* Grab a lock on a mutex. */
 329 static inline int
 330 __gthread_objc_mutex_lock(objc_mutex_t mutex)
 331 {
 332   if (__gthread_active_p ())
 333     return pthread_mutex_lock((pthread_mutex_t *)mutex->backend);
 334   else
 335     return 0;
 336 }
 337
 338 /* Try to grab a lock on a mutex. */
 339 static inline int
 340 __gthread_objc_mutex_trylock(objc_mutex_t mutex)
 341 {
 342   if (__gthread_active_p ())
 343     return pthread_mutex_trylock((pthread_mutex_t *)mutex->backend);
 344   else
 345     return 0;
 346 }
 347
 348 /* Unlock the mutex */
 349 static inline int
 350 __gthread_objc_mutex_unlock(objc_mutex_t mutex)
 351 {
 352   if (__gthread_active_p ())
 353     return pthread_mutex_unlock((pthread_mutex_t *)mutex->backend);
 354   else
 355     return 0;
 356 }
 357
 358 /* Backend condition mutex functions */
 359
 360 /* Allocate a condition. */
 361 static inline int
 362 __gthread_objc_condition_allocate(objc_condition_t condition)
 363 {
 364   if (__gthread_active_p ())
 365     {
 366       condition->backend = objc_malloc(sizeof(pthread_cond_t));
 367
 368       if (pthread_cond_init((pthread_cond_t *)condition->backend, NULL))
 369         {
 370           objc_free(condition->backend);
 371           condition->backend = NULL;
 372           return -1;
 373         }
 374     }
 375
 376   return 0;
 377 }
 378
 379 /* Deallocate a condition. */
 380 static inline int
 381 __gthread_objc_condition_deallocate(objc_condition_t condition)
 382 {
 383   if (__gthread_active_p ())
 384     {
 385       if (pthread_cond_destroy((pthread_cond_t *)condition->backend))
 386         return -1;
 387
 388       objc_free(condition->backend);
 389       condition->backend = NULL;
 390     }
 391   return 0;
 392 }
 393
 394 /* Wait on the condition */
 395 static inline int
 396 __gthread_objc_condition_wait(objc_condition_t condition, objc_mutex_t mutex)
 397 {
 398   if (__gthread_active_p ())
 399     return pthread_cond_wait((pthread_cond_t *)condition->backend,
 400                            (pthread_mutex_t *)mutex->backend);
 401   else
 402     return 0;
 403 }
 404
 405 /* Wake up all threads waiting on this condition. */
 406 static inline int
 407 __gthread_objc_condition_broadcast(objc_condition_t condition)
 408 {
 409   if (__gthread_active_p ())
 410     return pthread_cond_broadcast((pthread_cond_t *)condition->backend);
 411   else
 412     return 0;
 413 }
 414
 415 /* Wake up one thread waiting on this condition. */
 416 static inline int
 417 __gthread_objc_condition_signal(objc_condition_t condition)
 418 {
 419   if (__gthread_active_p ())
 420     return pthread_cond_signal((pthread_cond_t *)condition->backend);
 421   else
 422     return 0;
 423 }
 424
 425 #else /* _LIBOBJC */
 426
 427 static inline int
 428 __gthread_once (__gthread_once_t *once, void (*func) (void))
 429 {
 430   if (__gthread_active_p ())
 431     return pthread_once (once, func);
 432   else
 433     return -1;
 434 }
 435
 436 static inline int
 437 __gthread_key_create (__gthread_key_t *key, void (*dtor) (void *))
 438 {
 439   return pthread_key_create (key, dtor);
 440 }
 441
 442 static inline int
 443 __gthread_key_dtor (__gthread_key_t key, void *ptr)
 444 {
 445   /* Just reset the key value to zero. */
 446   if (ptr)
 447     return pthread_setspecific (key, 0);
 448   else
 449     return 0;
 450 }
 451
 452 static inline int
 453 __gthread_key_delete (__gthread_key_t key)
 454 {
 455   return pthread_key_delete (key);
 456 }
 457
 458 static inline void *
 459 __gthread_getspecific (__gthread_key_t key)
 460 {
 461   return pthread_getspecific (key);
 462 }
 463
 464 static inline int
 465 __gthread_setspecific (__gthread_key_t key, const void *ptr)
 466 {
 467   return pthread_setspecific (key, ptr);
 468 }
 469
 470 static inline int
 471 __gthread_mutex_lock (__gthread_mutex_t *mutex)
 472 {
 473   if (__gthread_active_p ())
 474     return pthread_mutex_lock (mutex);
 475   else
 476     return 0;
 477 }
 478
 479 static inline int
 480 __gthread_mutex_trylock (__gthread_mutex_t *mutex)
 481 {
 482   if (__gthread_active_p ())
 483     return pthread_mutex_trylock (mutex);
 484   else
 485     return 0;
 486 }
 487
 488 static inline int
 489 __gthread_mutex_unlock (__gthread_mutex_t *mutex)
 490 {
 491   if (__gthread_active_p ())
 492     return pthread_mutex_unlock (mutex);
 493   else
 494     return 0;
 495 }
 496
 497 #endif /* _LIBOBJC */
 498
 499 #endif /* not __gthr_posix_h */