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 #endif
  72
  73 static void *__gthread_active_ptr = &pthread_create;
  74
  75 static inline int
  76 __gthread_active_p (void)
  77 {
  78   return __gthread_active_ptr != 0;
  79 }
  80
  81 #else /* not SUPPORTS_WEAK */
  82
  83 static inline int
  84 __gthread_active_p (void)
  85 {
  86   return 1;
  87 }
  88
  89 #endif /* SUPPORTS_WEAK */
  90
  91 #ifdef _LIBOBJC
  92
  93 /* This is the config.h file in libobjc/ */
  94 #include <config.h>
  95
  96 #ifdef HAVE_SCHED_H
  97 # include <sched.h>
  98 #endif
  99
 100 /* Key structure for maintaining thread specific storage */
 101 static pthread_key_t _objc_thread_storage;
 102 static pthread_attr_t _objc_thread_attribs;
 103
 104 /* Thread local storage for a single thread */
 105 static void *thread_local_storage = NULL;
 106
 107 /* Backend initialization functions */
 108
 109 /* Initialize the threads subsystem. */
 110 static inline int
 111 __gthread_objc_init_thread_system(void)
 112 {
 113   if (__gthread_active_p ())
 114     {
 115       /* Initialize the thread storage key */
 116       if (pthread_key_create(&_objc_thread_storage, NULL) == 0)
 117         {
 118           /* The normal default detach state for threads is
 119            * PTHREAD_CREATE_JOINABLE which causes threads to not die
 120            * when you think they should.  */
 121           if (pthread_attr_init(&_objc_thread_attribs) == 0
 122               && pthread_attr_setdetachstate(&_objc_thread_attribs,
 123                                              PTHREAD_CREATE_DETACHED) == 0)
 124             return 0;
 125         }
 126     }
 127   else
 128     return -1;
 129 }
 130
 131 /* Close the threads subsystem. */
 132 static inline int
 133 __gthread_objc_close_thread_system(void)
 134 {
 135   if (__gthread_active_p ()
 136       && pthread_key_delete(_objc_thread_storage) == 0
 137       && pthread_attr_destroy(&_objc_thread_attribs) == 0)
 138     return 0;
 139
 140   return -1;
 141 }
 142
 143 /* Backend thread functions */
 144
 145 /* Create a new thread of execution. */
 146 static inline objc_thread_t
 147 __gthread_objc_thread_detach(void (*func)(void *), void *arg)
 148 {
 149   objc_thread_t thread_id;
 150   pthread_t new_thread_handle;
 151
 152   if (!__gthread_active_p ())
 153     return NULL;
 154
 155   if ( !(pthread_create(&new_thread_handle, NULL, (void *)func, arg)) )
 156     thread_id = *(objc_thread_t *)&new_thread_handle;
 157   else
 158     thread_id = NULL;
 159
 160   return thread_id;
 161 }
 162
 163 /* Set the current thread's priority. */
 164 static inline int
 165 __gthread_objc_thread_set_priority(int priority)
 166 {
 167   if (!__gthread_active_p())
 168     return -1;
 169   else {
 170     pthread_t thread_id = pthread_self();
 171     int policy;
 172     struct sched_param params;
 173     int priority_min, priority_max;
 174
 175     if (pthread_getschedparam(thread_id, &policy, &params) == 0)
 176       {
 177         if ((priority_max = sched_get_priority_max(policy)) != 0)
 178           return -1;
 179
 180         if ((priority_min = sched_get_priority_min(policy)) != 0)
 181           return -1;
 182
 183         if (priority > priority_max)
 184           priority = priority_max;
 185         else if (priority < priority_min)
 186           priority = priority_min;
 187         params.sched_priority = priority;
 188
 189         /*
 190          * The solaris 7 and several other man pages incorrectly state that
 191          * this should be a pointer to policy but pthread.h is universally
 192          * at odds with this.
 193          */
 194         if (pthread_setschedparam(thread_id, policy, &params) == 0)
 195           return 0;
 196       }
 197     return -1;
 198   }
 199 }
 200
 201 /* Return the current thread's priority. */
 202 static inline int
 203 __gthread_objc_thread_get_priority(void)
 204 {
 205   if (__gthread_active_p ())
 206     {
 207       int policy;
 208       struct sched_param params;
 209
 210       if (pthread_getschedparam(pthread_self(), &policy, &params) == 0)
 211         return params.sched_priority;
 212       else
 213         return -1;
 214     }
 215   else
 216     return OBJC_THREAD_INTERACTIVE_PRIORITY;
 217 }
 218
 219 /* Yield our process time to another thread. */
 220 static inline void
 221 __gthread_objc_thread_yield(void)
 222 {
 223   if (__gthread_active_p ())
 224     sched_yield();
 225 }
 226
 227 /* Terminate the current thread. */
 228 static inline int
 229 __gthread_objc_thread_exit(void)
 230 {
 231   if (__gthread_active_p ())
 232     /* exit the thread */
 233     pthread_exit(&__objc_thread_exit_status);
 234
 235   /* Failed if we reached here */
 236   return -1;
 237 }
 238
 239 /* Returns an integer value which uniquely describes a thread. */
 240 static inline objc_thread_t
 241 __gthread_objc_thread_id(void)
 242 {
 243   if (__gthread_active_p ())
 244     {
 245       pthread_t self = pthread_self();
 246
 247       return *(objc_thread_t *)&self;
 248     }
 249   else
 250     return (objc_thread_t)1;
 251 }
 252
 253 /* Sets the thread's local storage pointer. */
 254 static inline int
 255 __gthread_objc_thread_set_data(void *value)
 256 {
 257   if (__gthread_active_p ())
 258     return pthread_setspecific(_objc_thread_storage, value);
 259   else
 260     {
 261       thread_local_storage = value;
 262       return 0;
 263     }
 264 }
 265
 266 /* Returns the thread's local storage pointer. */
 267 static inline void *
 268 __gthread_objc_thread_get_data(void)
 269 {
 270   if (__gthread_active_p ())
 271     return pthread_getspecific(_objc_thread_storage);
 272   else
 273     return thread_local_storage;
 274 }
 275
 276 /* Backend mutex functions */
 277
 278 /* Allocate a mutex. */
 279 static inline int
 280 __gthread_objc_mutex_allocate(objc_mutex_t mutex)
 281 {
 282   if (__gthread_active_p ())
 283     {
 284       mutex->backend = objc_malloc(sizeof(pthread_mutex_t));
 285
 286       if (pthread_mutex_init((pthread_mutex_t *)mutex->backend, NULL))
 287         {
 288           objc_free(mutex->backend);
 289           mutex->backend = NULL;
 290           return -1;
 291         }
 292     }
 293
 294   return 0;
 295 }
 296
 297 /* Deallocate a mutex. */
 298 static inline int
 299 __gthread_objc_mutex_deallocate(objc_mutex_t mutex)
 300 {
 301   if (__gthread_active_p ())
 302     {
 303       int count;
 304
 305       /*
 306        * Posix Threads specifically require that the thread be unlocked
 307        * for pthread_mutex_destroy to work.
 308        */
 309
 310       do
 311         {
 312           count = pthread_mutex_unlock((pthread_mutex_t *)mutex->backend);
 313           if (count < 0)
 314             return -1;
 315         }
 316       while (count);
 317
 318       if (pthread_mutex_destroy((pthread_mutex_t *)mutex->backend))
 319         return -1;
 320
 321       objc_free(mutex->backend);
 322       mutex->backend = NULL;
 323     }
 324   return 0;
 325 }
 326
 327 /* Grab a lock on a mutex. */
 328 static inline int
 329 __gthread_objc_mutex_lock(objc_mutex_t mutex)
 330 {
 331   if (__gthread_active_p ())
 332     return pthread_mutex_lock((pthread_mutex_t *)mutex->backend);
 333   else
 334     return 0;
 335 }
 336
 337 /* Try to grab a lock on a mutex. */
 338 static inline int
 339 __gthread_objc_mutex_trylock(objc_mutex_t mutex)
 340 {
 341   if (__gthread_active_p ())
 342     return pthread_mutex_trylock((pthread_mutex_t *)mutex->backend);
 343   else
 344     return 0;
 345 }
 346
 347 /* Unlock the mutex */
 348 static inline int
 349 __gthread_objc_mutex_unlock(objc_mutex_t mutex)
 350 {
 351   if (__gthread_active_p ())
 352     return pthread_mutex_unlock((pthread_mutex_t *)mutex->backend);
 353   else
 354     return 0;
 355 }
 356
 357 /* Backend condition mutex functions */
 358
 359 /* Allocate a condition. */
 360 static inline int
 361 __gthread_objc_condition_allocate(objc_condition_t condition)
 362 {
 363   if (__gthread_active_p ())
 364     {
 365       condition->backend = objc_malloc(sizeof(pthread_cond_t));
 366
 367       if (pthread_cond_init((pthread_cond_t *)condition->backend, NULL))
 368         {
 369           objc_free(condition->backend);
 370           condition->backend = NULL;
 371           return -1;
 372         }
 373     }
 374
 375   return 0;
 376 }
 377
 378 /* Deallocate a condition. */
 379 static inline int
 380 __gthread_objc_condition_deallocate(objc_condition_t condition)
 381 {
 382   if (__gthread_active_p ())
 383     {
 384       if (pthread_cond_destroy((pthread_cond_t *)condition->backend))
 385         return -1;
 386
 387       objc_free(condition->backend);
 388       condition->backend = NULL;
 389     }
 390   return 0;
 391 }
 392
 393 /* Wait on the condition */
 394 static inline int
 395 __gthread_objc_condition_wait(objc_condition_t condition, objc_mutex_t mutex)
 396 {
 397   if (__gthread_active_p ())
 398     return pthread_cond_wait((pthread_cond_t *)condition->backend,
 399                            (pthread_mutex_t *)mutex->backend);
 400   else
 401     return 0;
 402 }
 403
 404 /* Wake up all threads waiting on this condition. */
 405 static inline int
 406 __gthread_objc_condition_broadcast(objc_condition_t condition)
 407 {
 408   if (__gthread_active_p ())
 409     return pthread_cond_broadcast((pthread_cond_t *)condition->backend);
 410   else
 411     return 0;
 412 }
 413
 414 /* Wake up one thread waiting on this condition. */
 415 static inline int
 416 __gthread_objc_condition_signal(objc_condition_t condition)
 417 {
 418   if (__gthread_active_p ())
 419     return pthread_cond_signal((pthread_cond_t *)condition->backend);
 420   else
 421     return 0;
 422 }
 423
 424 #else /* _LIBOBJC */
 425
 426 static inline int
 427 __gthread_once (__gthread_once_t *once, void (*func) (void))
 428 {
 429   if (__gthread_active_p ())
 430     return pthread_once (once, func);
 431   else
 432     return -1;
 433 }
 434
 435 static inline int
 436 __gthread_key_create (__gthread_key_t *key, void (*dtor) (void *))
 437 {
 438   return pthread_key_create (key, dtor);
 439 }
 440
 441 static inline int
 442 __gthread_key_dtor (__gthread_key_t key, void *ptr)
 443 {
 444   /* Just reset the key value to zero. */
 445   if (ptr)
 446     return pthread_setspecific (key, 0);
 447   else
 448     return 0;
 449 }
 450
 451 static inline int
 452 __gthread_key_delete (__gthread_key_t key)
 453 {
 454   return pthread_key_delete (key);
 455 }
 456
 457 static inline void *
 458 __gthread_getspecific (__gthread_key_t key)
 459 {
 460   return pthread_getspecific (key);
 461 }
 462
 463 static inline int
 464 __gthread_setspecific (__gthread_key_t key, const void *ptr)
 465 {
 466   return pthread_setspecific (key, ptr);
 467 }
 468
 469 static inline int
 470 __gthread_mutex_lock (__gthread_mutex_t *mutex)
 471 {
 472   if (__gthread_active_p ())
 473     return pthread_mutex_lock (mutex);
 474   else
 475     return 0;
 476 }
 477
 478 static inline int
 479 __gthread_mutex_trylock (__gthread_mutex_t *mutex)
 480 {
 481   if (__gthread_active_p ())
 482     return pthread_mutex_trylock (mutex);
 483   else
 484     return 0;
 485 }
 486
 487 static inline int
 488 __gthread_mutex_unlock (__gthread_mutex_t *mutex)
 489 {
 490   if (__gthread_active_p ())
 491     return pthread_mutex_unlock (mutex);
 492   else
 493     return 0;
 494 }
 495
 496 #endif /* _LIBOBJC */
 497
 498 #endif /* not __gthr_posix_h */