gcc/gthr-posix.h

   1 /* Threads compatibility routines for libgcc2 and libobjc.  */
   2 /* Compile this one with gcc.  */
   3 /* Copyright (C) 1997, 1999, 2000 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 = &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   else
 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     {
 250       pthread_t self = pthread_self();
 251
 252       return *(objc_thread_t *)&self;
 253     }
 254   else
 255     return (objc_thread_t)1;
 256 }
 257
 258 /* Sets the thread's local storage pointer. */
 259 static inline int
 260 __gthread_objc_thread_set_data(void *value)
 261 {
 262   if (__gthread_active_p ())
 263     return pthread_setspecific(_objc_thread_storage, value);
 264   else
 265     {
 266       thread_local_storage = value;
 267       return 0;
 268     }
 269 }
 270
 271 /* Returns the thread's local storage pointer. */
 272 static inline void *
 273 __gthread_objc_thread_get_data(void)
 274 {
 275   if (__gthread_active_p ())
 276     return pthread_getspecific(_objc_thread_storage);
 277   else
 278     return thread_local_storage;
 279 }
 280
 281 /* Backend mutex functions */
 282
 283 /* Allocate a mutex. */
 284 static inline int
 285 __gthread_objc_mutex_allocate(objc_mutex_t mutex)
 286 {
 287   if (__gthread_active_p ())
 288     {
 289       mutex->backend = objc_malloc(sizeof(pthread_mutex_t));
 290
 291       if (pthread_mutex_init((pthread_mutex_t *)mutex->backend, NULL))
 292         {
 293           objc_free(mutex->backend);
 294           mutex->backend = NULL;
 295           return -1;
 296         }
 297     }
 298
 299   return 0;
 300 }
 301
 302 /* Deallocate a mutex. */
 303 static inline int
 304 __gthread_objc_mutex_deallocate(objc_mutex_t mutex)
 305 {
 306   if (__gthread_active_p ())
 307     {
 308       int count;
 309
 310       /*
 311        * Posix Threads specifically require that the thread be unlocked
 312        * for pthread_mutex_destroy to work.
 313        */
 314
 315       do
 316         {
 317           count = pthread_mutex_unlock((pthread_mutex_t *)mutex->backend);
 318           if (count < 0)
 319             return -1;
 320         }
 321       while (count);
 322
 323       if (pthread_mutex_destroy((pthread_mutex_t *)mutex->backend))
 324         return -1;
 325
 326       objc_free(mutex->backend);
 327       mutex->backend = NULL;
 328     }
 329   return 0;
 330 }
 331
 332 /* Grab a lock on a mutex. */
 333 static inline int
 334 __gthread_objc_mutex_lock(objc_mutex_t mutex)
 335 {
 336   if (__gthread_active_p ())
 337     return pthread_mutex_lock((pthread_mutex_t *)mutex->backend);
 338   else
 339     return 0;
 340 }
 341
 342 /* Try to grab a lock on a mutex. */
 343 static inline int
 344 __gthread_objc_mutex_trylock(objc_mutex_t mutex)
 345 {
 346   if (__gthread_active_p ())
 347     return pthread_mutex_trylock((pthread_mutex_t *)mutex->backend);
 348   else
 349     return 0;
 350 }
 351
 352 /* Unlock the mutex */
 353 static inline int
 354 __gthread_objc_mutex_unlock(objc_mutex_t mutex)
 355 {
 356   if (__gthread_active_p ())
 357     return pthread_mutex_unlock((pthread_mutex_t *)mutex->backend);
 358   else
 359     return 0;
 360 }
 361
 362 /* Backend condition mutex functions */
 363
 364 /* Allocate a condition. */
 365 static inline int
 366 __gthread_objc_condition_allocate(objc_condition_t condition)
 367 {
 368   if (__gthread_active_p ())
 369     {
 370       condition->backend = objc_malloc(sizeof(pthread_cond_t));
 371
 372       if (pthread_cond_init((pthread_cond_t *)condition->backend, NULL))
 373         {
 374           objc_free(condition->backend);
 375           condition->backend = NULL;
 376           return -1;
 377         }
 378     }
 379
 380   return 0;
 381 }
 382
 383 /* Deallocate a condition. */
 384 static inline int
 385 __gthread_objc_condition_deallocate(objc_condition_t condition)
 386 {
 387   if (__gthread_active_p ())
 388     {
 389       if (pthread_cond_destroy((pthread_cond_t *)condition->backend))
 390         return -1;
 391
 392       objc_free(condition->backend);
 393       condition->backend = NULL;
 394     }
 395   return 0;
 396 }
 397
 398 /* Wait on the condition */
 399 static inline int
 400 __gthread_objc_condition_wait(objc_condition_t condition, objc_mutex_t mutex)
 401 {
 402   if (__gthread_active_p ())
 403     return pthread_cond_wait((pthread_cond_t *)condition->backend,
 404                            (pthread_mutex_t *)mutex->backend);
 405   else
 406     return 0;
 407 }
 408
 409 /* Wake up all threads waiting on this condition. */
 410 static inline int
 411 __gthread_objc_condition_broadcast(objc_condition_t condition)
 412 {
 413   if (__gthread_active_p ())
 414     return pthread_cond_broadcast((pthread_cond_t *)condition->backend);
 415   else
 416     return 0;
 417 }
 418
 419 /* Wake up one thread waiting on this condition. */
 420 static inline int
 421 __gthread_objc_condition_signal(objc_condition_t condition)
 422 {
 423   if (__gthread_active_p ())
 424     return pthread_cond_signal((pthread_cond_t *)condition->backend);
 425   else
 426     return 0;
 427 }
 428
 429 #else /* _LIBOBJC */
 430
 431 static inline int
 432 __gthread_once (__gthread_once_t *once, void (*func) (void))
 433 {
 434   if (__gthread_active_p ())
 435     return pthread_once (once, func);
 436   else
 437     return -1;
 438 }
 439
 440 static inline int
 441 __gthread_key_create (__gthread_key_t *key, void (*dtor) (void *))
 442 {
 443   return pthread_key_create (key, dtor);
 444 }
 445
 446 static inline int
 447 __gthread_key_dtor (__gthread_key_t key, void *ptr)
 448 {
 449   /* Just reset the key value to zero. */
 450   if (ptr)
 451     return pthread_setspecific (key, 0);
 452   else
 453     return 0;
 454 }
 455
 456 static inline int
 457 __gthread_key_delete (__gthread_key_t key)
 458 {
 459   return pthread_key_delete (key);
 460 }
 461
 462 static inline void *
 463 __gthread_getspecific (__gthread_key_t key)
 464 {
 465   return pthread_getspecific (key);
 466 }
 467
 468 static inline int
 469 __gthread_setspecific (__gthread_key_t key, const void *ptr)
 470 {
 471   return pthread_setspecific (key, ptr);
 472 }
 473
 474 static inline int
 475 __gthread_mutex_lock (__gthread_mutex_t *mutex)
 476 {
 477   if (__gthread_active_p ())
 478     return pthread_mutex_lock (mutex);
 479   else
 480     return 0;
 481 }
 482
 483 static inline int
 484 __gthread_mutex_trylock (__gthread_mutex_t *mutex)
 485 {
 486   if (__gthread_active_p ())
 487     return pthread_mutex_trylock (mutex);
 488   else
 489     return 0;
 490 }
 491
 492 static inline int
 493 __gthread_mutex_unlock (__gthread_mutex_t *mutex)
 494 {
 495   if (__gthread_active_p ())
 496     return pthread_mutex_unlock (mutex);
 497   else
 498     return 0;
 499 }
 500
 501 #endif /* _LIBOBJC */
 502
 503 #endif /* not __gthr_posix_h */