pthreads/pthread_cancelable.c

   1 /*
   2  * Copyright (c) 2000-2008 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23 /*
  24  * Copyright 1996 1995 by Open Software Foundation, Inc. 1997 1996 1995 1994 1993 1992 1991
  25  *              All Rights Reserved
  26  *
  27  * Permission to use, copy, modify, and distribute this software and
  28  * its documentation for any purpose and without fee is hereby granted,
  29  * provided that the above copyright notice appears in all copies and
  30  * that both the copyright notice and this permission notice appear in
  31  * supporting documentation.
  32  *
  33  * OSF DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE
  34  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  35  * FOR A PARTICULAR PURPOSE.
  36  *
  37  * IN NO EVENT SHALL OSF BE LIABLE FOR ANY SPECIAL, INDIRECT, OR
  38  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
  39  * LOSS OF USE, DATA OR PROFITS, WHETHER IN ACTION OF CONTRACT,
  40  * NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
  41  * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  42  *
  43  */
  44 /*
  45  * MkLinux
  46  */
  47
  48 /*
  49  * POSIX Pthread Library
  50  */
  51
  52 #include "pthread_internals.h"
  53
  54 #include <assert.h>
  55 #include <stdio.h>      /* For printf(). */
  56 #include <stdlib.h>
  57 #include <errno.h>      /* For __mach_errno_addr() prototype. */
  58 #include <signal.h>
  59 #include <sys/time.h>
  60 #include <sys/resource.h>
  61 #include <sys/sysctl.h>
  62 #include <sys/queue.h>
  63 #include <machine/vmparam.h>
  64 #include <mach/vm_statistics.h>
  65
  66 extern int __unix_conforming;
  67 extern void __posix_join_cleanup(void *arg);
  68 extern pthread_lock_t _pthread_list_lock;
  69 extern void _pthread_testcancel(pthread_t thread, int isconforming);
  70 extern int _pthread_reap_thread(pthread_t th, mach_port_t kernel_thread, void **value_ptr, int conforming);
  71 extern int _pthread_cond_wait(pthread_cond_t *cond,
  72                         pthread_mutex_t *mutex,
  73                         const struct timespec *abstime,
  74                         int isRelative,
  75                         int isconforming);
  76 extern int __sigwait(const sigset_t *set, int *sig);
  77
  78 #ifdef VARIANT_CANCELABLE
  79 extern int __semwait_signal(int cond_sem, int mutex_sem, int timeout, int relative, __int64_t tv_sec, __int32_t tv_nsec);
  80 #else
  81 extern int __semwait_signal(int cond_sem, int mutex_sem, int timeout, int relative, __int64_t tv_sec, __int32_t tv_nsec)  __asm__("___semwait_signal_nocancel");
  82 #endif
  83
  84 /*
  85  * Wait for a thread to terminate and obtain its exit value.
  86  */
  87 int
  88 pthread_join(pthread_t thread,
  89              void **value_ptr)
  90 {
  91         int res = 0;
  92         pthread_t self = pthread_self();
  93         mach_port_t kthport;
  94         int conforming = 0;
  95 #if !__DARWIN_UNIX03
  96         kern_return_t kern_res;
  97 #endif
  98
  99 #if __DARWIN_UNIX03
 100         if (__unix_conforming == 0)
 101                 __unix_conforming = 1;
 102
 103 #ifdef VARIANT_CANCELABLE
 104         _pthread_testcancel(self, 1);
 105 #endif /* VARIANT_CANCELABLE */
 106 #endif /* __DARWIN_UNIX03 */
 107
 108         if ((res = _pthread_lookup_thread(thread, &kthport, 1)) != 0)
 109                 return(res);
 110
 111         if (thread->sig == _PTHREAD_SIG)
 112         {
 113         if (thread->newstyle == 0) {
 114                 semaphore_t death = new_sem_from_pool(); /* in case we need it */
 115
 116                 LOCK(thread->lock);
 117                 if ((thread->detached & PTHREAD_CREATE_JOINABLE) &&
 118                         thread->death == SEMAPHORE_NULL)
 119                 {
 120
 121                         assert(thread->joiner == NULL);
 122                         if (thread != self && (self == NULL || self->joiner != thread))
 123                         {
 124                                 int already_exited = (thread->detached & _PTHREAD_EXITED);
 125
 126                                 thread->death = death;
 127                                 thread->joiner = self;
 128                                 UNLOCK(thread->lock);
 129
 130                                 if (!already_exited)
 131                                 {
 132 #if __DARWIN_UNIX03
 133                                         /* Wait for it to signal... */
 134                                         pthread_cleanup_push(__posix_join_cleanup, (void *)thread);
 135                                         do {
 136                                                 res = __semwait_signal(death, 0, 0, 0, (int64_t)0, (int32_t)0);
 137                                         } while ((res < 0) && (errno == EINTR));
 138                                         pthread_cleanup_pop(0);
 139
 140 #else /* __DARWIN_UNIX03 */
 141                                         /* Wait for it to signal... */
 142                                         do {
 143                                                 PTHREAD_MACH_CALL(semaphore_wait(death), kern_res);
 144                                         } while (kern_res != KERN_SUCCESS);
 145 #endif /* __DARWIN_UNIX03 */
 146                                 }
 147
 148                                 LOCK(_pthread_list_lock);
 149                                 TAILQ_REMOVE(&__pthread_head, thread, plist);
 150 #if WQ_TRACE
 151                                 __kdebug_trace(0x9000010, thread, 0, 0, 16, 0);
 152 #endif
 153                                 UNLOCK(_pthread_list_lock);
 154                                 /* ... and wait for it to really be dead */
 155                                 while ((res = _pthread_reap_thread(thread,
 156                                                         thread->kernel_thread,
 157                                                         value_ptr, __unix_conforming)) == EAGAIN)
 158                                 {
 159                                         sched_yield();
 160                                 }
 161
 162                         } else {
 163                                 UNLOCK(thread->lock);
 164                                 res = EDEADLK;
 165                         }
 166                 } else {
 167                         UNLOCK(thread->lock);
 168                         res = EINVAL;
 169                 }
 170                 restore_sem_to_pool(death);
 171                 return res;
 172         } else {
 173                 /* new style */
 174
 175                 semaphore_t death = SEMAPHORE_NULL; /* in case we need it */
 176                 semaphore_t joinsem = SEMAPHORE_NULL;
 177
 178                 if (thread->joiner_notify == MACH_PORT_NULL)
 179                          death = new_sem_from_pool();
 180
 181                 LOCK(thread->lock);
 182                 if ((thread->detached & PTHREAD_CREATE_JOINABLE) &&
 183                         (thread->joiner == NULL))
 184                 {
 185                         assert(thread->kernel_thread == kthport);
 186                         if (thread != self && (self == NULL || self->joiner != thread))
 187                         {
 188                                 if (thread->joiner_notify == MACH_PORT_NULL) {
 189                                         if (death == SEMAPHORE_NULL)
 190                                                 LIBC_ABORT("thread %p: death == SEMAPHORE_NULL", thread);
 191                                         thread->joiner_notify = death;
 192                                         death = SEMAPHORE_NULL;
 193                                 }
 194                                 joinsem = thread->joiner_notify;
 195                                 thread->joiner = self;
 196                                 UNLOCK(thread->lock);
 197
 198                                 if (death != SEMAPHORE_NULL) {
 199                                         restore_sem_to_pool(death);
 200                                         death = SEMAPHORE_NULL;
 201                                 }
 202 #if __DARWIN_UNIX03
 203                                 /* Wait for it to signal... */
 204                                 pthread_cleanup_push(__posix_join_cleanup, (void *)thread);
 205                                 do {
 206                                         res = __semwait_signal(joinsem, 0, 0, 0, (int64_t)0, (int32_t)0);
 207                                 } while ((res < 0) && (errno == EINTR));
 208                                 pthread_cleanup_pop(0);
 209 #else /* __DARWIN_UNIX03 */
 210                                 /* Wait for it to signal... */
 211                                 do {
 212                                         PTHREAD_MACH_CALL(semaphore_wait(joinsem), kern_res);
 213                                 } while (kern_res != KERN_SUCCESS);
 214 #endif /* __DARWIN_UNIX03 */
 215
 216                                 restore_sem_to_pool(joinsem);
 217                                 res = _pthread_join_cleanup(thread, value_ptr, conforming);
 218                         } else {
 219                                 UNLOCK(thread->lock);
 220                                 res = EDEADLK;
 221                         }
 222                 } else {
 223                         UNLOCK(thread->lock);
 224                         res = EINVAL;
 225                 }
 226                 if (death != SEMAPHORE_NULL)
 227                         restore_sem_to_pool(death);
 228                 return res;
 229         }/* end of new style */
 230         }
 231         return ESRCH;
 232 }
 233
 234 int
 235 pthread_cond_wait(pthread_cond_t *cond,
 236                   pthread_mutex_t *mutex)
 237 {
 238         int conforming;
 239 #if __DARWIN_UNIX03
 240
 241         if (__unix_conforming == 0)
 242                 __unix_conforming = 1;
 243
 244 #ifdef VARIANT_CANCELABLE
 245         conforming = 1;
 246 #else /* !VARIANT_CANCELABLE */
 247         conforming = -1;
 248 #endif /* VARIANT_CANCELABLE */
 249 #else /* __DARWIN_UNIX03 */
 250         conforming = 0;
 251 #endif /* __DARWIN_UNIX03 */
 252         return (_pthread_cond_wait(cond, mutex, (struct timespec *)NULL, 0, conforming));
 253 }
 254
 255 int
 256 pthread_cond_timedwait(pthread_cond_t *cond,
 257                        pthread_mutex_t *mutex,
 258                        const struct timespec *abstime)
 259 {
 260         int conforming;
 261 #if __DARWIN_UNIX03
 262         if (__unix_conforming == 0)
 263                 __unix_conforming = 1;
 264
 265 #ifdef VARIANT_CANCELABLE
 266         conforming = 1;
 267 #else /* !VARIANT_CANCELABLE */
 268         conforming = -1;
 269 #endif /* VARIANT_CANCELABLE */
 270 #else /* __DARWIN_UNIX03 */
 271         conforming = 0;
 272 #endif /* __DARWIN_UNIX03 */
 273
 274         return (_pthread_cond_wait(cond, mutex, abstime, 0, conforming));
 275 }
 276
 277 int
 278 sigwait(const sigset_t * set, int * sig)
 279 {
 280 #if __DARWIN_UNIX03
 281         int err = 0;
 282
 283         if (__unix_conforming == 0)
 284                 __unix_conforming = 1;
 285
 286 #ifdef VARIANT_CANCELABLE
 287         _pthread_testcancel(pthread_self(), 1);
 288 #endif /* VARIANT_CANCELABLE */
 289
 290         if (__sigwait(set, sig) == -1) {
 291                 err = errno;
 292
 293 #ifdef VARIANT_CANCELABLE
 294                 _pthread_testcancel(pthread_self(), 1);
 295 #endif /* VARIANT_CANCELABLE */
 296
 297                 /*
 298                  * EINTR that isn't a result of pthread_cancel()
 299                  * is translated to 0.
 300                  */
 301                 if (err == EINTR) {
 302                         err = 0;
 303                 }
 304         }
 305         return(err);
 306 #else /* __DARWIN_UNIX03 */
 307         if (__sigwait(set, sig) == -1) {
 308                 /*
 309                  * EINTR that isn't a result of pthread_cancel()
 310                  * is translated to 0.
 311                  */
 312                 if (errno != EINTR) {
 313                         return -1;
 314                 }
 315         }
 316
 317         return 0;
 318 #endif /* __DARWIN_UNIX03 */
 319 }