1 /* GLIB - Library of useful routines for C programming 2 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald 3 * 4 * gthread.c: posix thread system implementation 5 * Copyright 1998 Sebastian Wilhelmi; University of Karlsruhe 6 * 7 * This library is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2 of the License, or (at your option) any later version. 11 * 12 * This library 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 GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with this library; if not, write to the 19 * Free Software Foundation, Inc., 59 Temple Place - Suite 330, 20 * Boston, MA 02111-1307, USA. 21 */ 22 23 /* 24 * Modified by the GLib Team and others 1997-2000. See the AUTHORS 25 * file for a list of people on the GLib Team. See the ChangeLog 26 * files for a list of changes. These files are distributed with 27 * GLib at ftp://ftp.gtk.org/pub/gtk/. 28 */ 29 30 /* 31 * MT safe 32 */ 33 34 #include "config.h" 35 36 #include <pthread.h> 37 #include <errno.h> 38 #include <stdlib.h> 39 #ifdef HAVE_SYS_TIME_H 40 # include <sys/time.h> 41 #endif 42 #ifdef HAVE_UNISTD_H 43 # include <unistd.h> 44 #endif 45 46 #ifdef HAVE_SCHED_H 47 #include <sched.h> 48 #endif 49 50 #define posix_check_err(err, name) G_STMT_START{ \ 51 int error = (err); \ 52 if (error) \ 53 g_error ("file %s: line %d (%s): error '%s' during '%s'", \ 54 __FILE__, __LINE__, G_STRFUNC, \ 55 g_strerror (error), name); \ 56 }G_STMT_END 57 58 #define posix_check_cmd(cmd) posix_check_err (posix_error (cmd), #cmd) 59 60 #ifdef G_ENABLE_DEBUG 61 static gboolean posix_check_cmd_prio_warned = FALSE; 62 # define posix_check_cmd_prio(cmd) G_STMT_START{ \ 63 int err = posix_error (cmd); \ 64 if (err == EPERM) \ 65 { \ 66 if (!posix_check_cmd_prio_warned) \ 67 { \ 68 posix_check_cmd_prio_warned = TRUE; \ 69 g_warning ("Priorities can only be changed " \ 70 "(resp. increased) by root."); \ 71 } \ 72 } \ 73 else \ 74 posix_check_err (err, #cmd); \ 75 }G_STMT_END 76 #else /* G_ENABLE_DEBUG */ 77 # define posix_check_cmd_prio(cmd) G_STMT_START{ \ 78 int err = posix_error (cmd); \ 79 if (err != EPERM) \ 80 posix_check_err (err, #cmd); \ 81 }G_STMT_END 82 #endif /* G_ENABLE_DEBUG */ 83 84 #if defined(G_THREADS_IMPL_POSIX) 85 # define posix_error(what) (what) 86 # define mutexattr_default NULL 87 # define condattr_default NULL 88 #elif defined(G_THREADS_IMPL_DCE) 89 # define posix_error(what) ((what) == -1 ? errno : 0) 90 # define pthread_key_create(a, b) pthread_keycreate (a, b) 91 # define pthread_attr_init(a) pthread_attr_create (a) 92 # define pthread_attr_destroy(a) pthread_attr_delete (a) 93 # define pthread_create(a, b, c, d) pthread_create (a, *b, c, d) 94 # define mutexattr_default (pthread_mutexattr_default) 95 # define condattr_default (pthread_condattr_default) 96 #else /* neither G_THREADS_IMPL_POSIX nor G_THREADS_IMPL_DCE are defined */ 97 # error This should not happen. Contact the GLib team. 98 #endif 99 100 #if defined (POSIX_MIN_PRIORITY) && defined (POSIX_MAX_PRIORITY) 101 # define HAVE_PRIORITIES 1 102 static gint priority_normal_value; 103 # ifdef __FreeBSD__ 104 /* FreeBSD threads use different priority values from the POSIX_ 105 * defines so we just set them here. The corresponding macros 106 * PTHREAD_MIN_PRIORITY and PTHREAD_MAX_PRIORITY are implied to be 107 * exported by the docs, but they aren't. 108 */ 109 # define PRIORITY_LOW_VALUE 0 110 # define PRIORITY_URGENT_VALUE 31 111 # else /* !__FreeBSD__ */ 112 # define PRIORITY_LOW_VALUE POSIX_MIN_PRIORITY 113 # define PRIORITY_URGENT_VALUE POSIX_MAX_PRIORITY 114 # endif /* !__FreeBSD__ */ 115 # define PRIORITY_NORMAL_VALUE priority_normal_value 116 #endif /* POSIX_MIN_PRIORITY && POSIX_MAX_PRIORITY */ 117 118 static gulong g_thread_min_stack_size = 0; 119 120 #define G_MUTEX_SIZE (sizeof (pthread_mutex_t)) 121 122 #if defined(HAVE_CLOCK_GETTIME) && defined(HAVE_MONOTONIC_CLOCK) 123 #define USE_CLOCK_GETTIME 1 124 static gint posix_clock = 0; 125 #endif 126 127 #if defined(_SC_THREAD_STACK_MIN) || defined (HAVE_PRIORITIES) || defined (USE_CLOCK_GETTIME) 128 #define HAVE_G_THREAD_IMPL_INIT 129 static void 130 g_thread_impl_init(void) 131 { 132 #ifdef _SC_THREAD_STACK_MIN 133 g_thread_min_stack_size = MAX (sysconf (_SC_THREAD_STACK_MIN), 0); 134 #endif /* _SC_THREAD_STACK_MIN */ 135 #ifdef HAVE_PRIORITIES 136 # ifdef G_THREADS_IMPL_POSIX 137 { 138 struct sched_param sched; 139 int policy; 140 posix_check_cmd (pthread_getschedparam (pthread_self(), &policy, &sched)); 141 priority_normal_value = sched.sched_priority; 142 } 143 # else /* G_THREADS_IMPL_DCE */ 144 posix_check_cmd (priority_normal_value = 145 pthread_getprio (*(pthread_t*)thread, 146 g_thread_priority_map [priority])); 147 # endif 148 #endif /* HAVE_PRIORITIES */ 149 150 #ifdef USE_CLOCK_GETTIME 151 if (sysconf (_SC_MONOTONIC_CLOCK) >= 0) 152 posix_clock = CLOCK_MONOTONIC; 153 else 154 posix_clock = CLOCK_REALTIME; 155 #endif 156 } 157 #endif /* _SC_THREAD_STACK_MIN || HAVE_PRIORITIES */ 158 159 static GMutex * 160 g_mutex_new_posix_impl (void) 161 { 162 GMutex *result = (GMutex *) g_new (pthread_mutex_t, 1); 163 posix_check_cmd (pthread_mutex_init ((pthread_mutex_t *) result, 164 mutexattr_default)); 165 return result; 166 } 167 168 static void 169 g_mutex_free_posix_impl (GMutex * mutex) 170 { 171 posix_check_cmd (pthread_mutex_destroy ((pthread_mutex_t *) mutex)); 172 g_free (mutex); 173 } 174 175 /* NOTE: the functions g_mutex_lock and g_mutex_unlock may not use 176 functions from gmem.c and gmessages.c; */ 177 178 /* pthread_mutex_lock, pthread_mutex_unlock can be taken directly, as 179 signature and semantic are right, but without error check then!!!!, 180 we might want to change this therefore. */ 181 182 static gboolean 183 g_mutex_trylock_posix_impl (GMutex * mutex) 184 { 185 int result; 186 187 result = pthread_mutex_trylock ((pthread_mutex_t *) mutex); 188 189 #ifdef G_THREADS_IMPL_POSIX 190 if (result == EBUSY) 191 return FALSE; 192 #else /* G_THREADS_IMPL_DCE */ 193 if (result == 0) 194 return FALSE; 195 #endif 196 197 posix_check_err (posix_error (result), "pthread_mutex_trylock"); 198 return TRUE; 199 } 200 201 static GCond * 202 g_cond_new_posix_impl (void) 203 { 204 GCond *result = (GCond *) g_new (pthread_cond_t, 1); 205 posix_check_cmd (pthread_cond_init ((pthread_cond_t *) result, 206 condattr_default)); 207 return result; 208 } 209 210 /* pthread_cond_signal, pthread_cond_broadcast and pthread_cond_wait 211 can be taken directly, as signature and semantic are right, but 212 without error check then!!!!, we might want to change this 213 therefore. */ 214 215 #define G_NSEC_PER_SEC 1000000000 216 217 static gboolean 218 g_cond_timed_wait_posix_impl (GCond * cond, 219 GMutex * entered_mutex, 220 GTimeVal * abs_time) 221 { 222 int result; 223 struct timespec end_time; 224 gboolean timed_out; 225 226 g_return_val_if_fail (cond != NULL, FALSE); 227 g_return_val_if_fail (entered_mutex != NULL, FALSE); 228 229 if (!abs_time) 230 { 231 result = pthread_cond_wait ((pthread_cond_t *)cond, 232 (pthread_mutex_t *) entered_mutex); 233 timed_out = FALSE; 234 } 235 else 236 { 237 end_time.tv_sec = abs_time->tv_sec; 238 end_time.tv_nsec = abs_time->tv_usec * (G_NSEC_PER_SEC / G_USEC_PER_SEC); 239 240 g_return_val_if_fail (end_time.tv_nsec < G_NSEC_PER_SEC, TRUE); 241 242 result = pthread_cond_timedwait ((pthread_cond_t *) cond, 243 (pthread_mutex_t *) entered_mutex, 244 &end_time); 245 #ifdef G_THREADS_IMPL_POSIX 246 timed_out = (result == ETIMEDOUT); 247 #else /* G_THREADS_IMPL_DCE */ 248 timed_out = (result == -1) && (errno == EAGAIN); 249 #endif 250 } 251 252 if (!timed_out) 253 posix_check_err (posix_error (result), "pthread_cond_timedwait"); 254 255 return !timed_out; 256 } 257 258 static void 259 g_cond_free_posix_impl (GCond * cond) 260 { 261 posix_check_cmd (pthread_cond_destroy ((pthread_cond_t *) cond)); 262 g_free (cond); 263 } 264 265 static GPrivate * 266 g_private_new_posix_impl (GDestroyNotify destructor) 267 { 268 GPrivate *result = (GPrivate *) g_new (pthread_key_t, 1); 269 posix_check_cmd (pthread_key_create ((pthread_key_t *) result, destructor)); 270 return result; 271 } 272 273 /* NOTE: the functions g_private_get and g_private_set may not use 274 functions from gmem.c and gmessages.c */ 275 276 static void 277 g_private_set_posix_impl (GPrivate * private_key, gpointer value) 278 { 279 if (!private_key) 280 return; 281 pthread_setspecific (*(pthread_key_t *) private_key, value); 282 } 283 284 static gpointer 285 g_private_get_posix_impl (GPrivate * private_key) 286 { 287 if (!private_key) 288 return NULL; 289 #ifdef G_THREADS_IMPL_POSIX 290 return pthread_getspecific (*(pthread_key_t *) private_key); 291 #else /* G_THREADS_IMPL_DCE */ 292 { 293 void* data; 294 posix_check_cmd (pthread_getspecific (*(pthread_key_t *) private_key, 295 &data)); 296 return data; 297 } 298 #endif 299 } 300 301 static void 302 g_thread_create_posix_impl (GThreadFunc thread_func, 303 gpointer arg, 304 gulong stack_size, 305 gboolean joinable, 306 gboolean bound, 307 GThreadPriority priority, 308 gpointer thread, 309 GError **error) 310 { 311 pthread_attr_t attr; 312 gint ret; 313 314 g_return_if_fail (thread_func); 315 g_return_if_fail (priority >= G_THREAD_PRIORITY_LOW); 316 g_return_if_fail (priority <= G_THREAD_PRIORITY_URGENT); 317 318 posix_check_cmd (pthread_attr_init (&attr)); 319 320 #ifdef HAVE_PTHREAD_ATTR_SETSTACKSIZE 321 if (stack_size) 322 { 323 stack_size = MAX (g_thread_min_stack_size, stack_size); 324 /* No error check here, because some systems can't do it and 325 * we simply don't want threads to fail because of that. */ 326 pthread_attr_setstacksize (&attr, stack_size); 327 } 328 #endif /* HAVE_PTHREAD_ATTR_SETSTACKSIZE */ 329 330 #ifdef PTHREAD_SCOPE_SYSTEM 331 if (bound) 332 /* No error check here, because some systems can't do it and we 333 * simply don't want threads to fail because of that. */ 334 pthread_attr_setscope (&attr, PTHREAD_SCOPE_SYSTEM); 335 #endif /* PTHREAD_SCOPE_SYSTEM */ 336 337 #ifdef G_THREADS_IMPL_POSIX 338 posix_check_cmd (pthread_attr_setdetachstate (&attr, 339 joinable ? PTHREAD_CREATE_JOINABLE : PTHREAD_CREATE_DETACHED)); 340 #endif /* G_THREADS_IMPL_POSIX */ 341 342 #ifdef HAVE_PRIORITIES 343 # ifdef G_THREADS_IMPL_POSIX 344 { 345 struct sched_param sched; 346 posix_check_cmd (pthread_attr_getschedparam (&attr, &sched)); 347 sched.sched_priority = g_thread_priority_map [priority]; 348 posix_check_cmd_prio (pthread_attr_setschedparam (&attr, &sched)); 349 } 350 # else /* G_THREADS_IMPL_DCE */ 351 posix_check_cmd_prio 352 (pthread_attr_setprio (&attr, g_thread_priority_map [priority])); 353 # endif /* G_THREADS_IMPL_DCE */ 354 #endif /* HAVE_PRIORITIES */ 355 ret = posix_error (pthread_create (thread, &attr, 356 (void* (*)(void*))thread_func, arg)); 357 358 posix_check_cmd (pthread_attr_destroy (&attr)); 359 360 if (ret == EAGAIN) 361 { 362 g_set_error (error, G_THREAD_ERROR, G_THREAD_ERROR_AGAIN, 363 "Error creating thread: %s", g_strerror (ret)); 364 return; 365 } 366 367 posix_check_err (ret, "pthread_create"); 368 369 #ifdef G_THREADS_IMPL_DCE 370 if (!joinable) 371 posix_check_cmd (pthread_detach (thread)); 372 #endif /* G_THREADS_IMPL_DCE */ 373 } 374 375 static void 376 g_thread_yield_posix_impl (void) 377 { 378 POSIX_YIELD_FUNC; 379 } 380 381 static void 382 g_thread_join_posix_impl (gpointer thread) 383 { 384 gpointer ignore; 385 posix_check_cmd (pthread_join (*(pthread_t*)thread, &ignore)); 386 } 387 388 static void 389 g_thread_exit_posix_impl (void) 390 { 391 pthread_exit (NULL); 392 } 393 394 static void 395 g_thread_set_priority_posix_impl (gpointer thread, GThreadPriority priority) 396 { 397 g_return_if_fail (priority >= G_THREAD_PRIORITY_LOW); 398 g_return_if_fail (priority <= G_THREAD_PRIORITY_URGENT); 399 #ifdef HAVE_PRIORITIES 400 # ifdef G_THREADS_IMPL_POSIX 401 { 402 struct sched_param sched; 403 int policy; 404 posix_check_cmd (pthread_getschedparam (*(pthread_t*)thread, &policy, 405 &sched)); 406 sched.sched_priority = g_thread_priority_map [priority]; 407 posix_check_cmd_prio (pthread_setschedparam (*(pthread_t*)thread, policy, 408 &sched)); 409 } 410 # else /* G_THREADS_IMPL_DCE */ 411 posix_check_cmd_prio (pthread_setprio (*(pthread_t*)thread, 412 g_thread_priority_map [priority])); 413 # endif 414 #endif /* HAVE_PRIORITIES */ 415 } 416 417 static void 418 g_thread_self_posix_impl (gpointer thread) 419 { 420 *(pthread_t*)thread = pthread_self(); 421 } 422 423 static gboolean 424 g_thread_equal_posix_impl (gpointer thread1, gpointer thread2) 425 { 426 return (pthread_equal (*(pthread_t*)thread1, *(pthread_t*)thread2) != 0); 427 } 428 429 #ifdef USE_CLOCK_GETTIME 430 static guint64 431 gettime (void) 432 { 433 struct timespec tv; 434 435 clock_gettime (posix_clock, &tv); 436 437 return (guint64) tv.tv_sec * G_NSEC_PER_SEC + tv.tv_nsec; 438 } 439 static guint64 (*g_thread_gettime_impl)(void) = gettime; 440 #else 441 static guint64 (*g_thread_gettime_impl)(void) = 0; 442 #endif 443 444 static GThreadFunctions g_thread_functions_for_glib_use_default = 445 { 446 g_mutex_new_posix_impl, 447 (void (*)(GMutex *)) pthread_mutex_lock, 448 g_mutex_trylock_posix_impl, 449 (void (*)(GMutex *)) pthread_mutex_unlock, 450 g_mutex_free_posix_impl, 451 g_cond_new_posix_impl, 452 (void (*)(GCond *)) pthread_cond_signal, 453 (void (*)(GCond *)) pthread_cond_broadcast, 454 (void (*)(GCond *, GMutex *)) pthread_cond_wait, 455 g_cond_timed_wait_posix_impl, 456 g_cond_free_posix_impl, 457 g_private_new_posix_impl, 458 g_private_get_posix_impl, 459 g_private_set_posix_impl, 460 g_thread_create_posix_impl, 461 g_thread_yield_posix_impl, 462 g_thread_join_posix_impl, 463 g_thread_exit_posix_impl, 464 g_thread_set_priority_posix_impl, 465 g_thread_self_posix_impl, 466 g_thread_equal_posix_impl 467 }; 468
