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 __semwait_signal(int cond_sem, int mutex_sem, int timeout, int relative, __int64_t tv_sec, __int32_t tv_nsec);
  77 extern int __sigwait(const sigset_t *set, int *sig);
  78
  79 /*
  80  * Wait for a thread to terminate and obtain its exit value.
  81  */
  82 int
  83 pthread_join(pthread_t thread,
  84              void **value_ptr)
  85 {
  86         int res = 0;
  87         pthread_t self = pthread_self();
  88         mach_port_t kthport;
  89         int conforming = 0;
  90 #if !__DARWIN_UNIX03
  91         kern_return_t kern_res;
  92 #endif
  93
  94 #if __DARWIN_UNIX03
  95         if (__unix_conforming == 0)
  96                 __unix_conforming = 1;
  97
  98 #ifdef VARIANT_CANCELABLE
  99         _pthread_testcancel(self, 1);
 100 #endif /* VARIANT_CANCELABLE */
 101 #endif /* __DARWIN_UNIX03 */
 102
 103         if ((res = _pthread_lookup_thread(thread, &kthport, 1)) != 0)
 104                 return(res);
 105
 106         if (thread->sig == _PTHREAD_SIG)
 107         {
 108         if (thread->newstyle == 0) {
 109                 semaphore_t death = new_sem_from_pool(); /* in case we need it */
 110
 111                 LOCK(thread->lock);
 112                 if ((thread->detached & PTHREAD_CREATE_JOINABLE) &&
 113                         thread->death == SEMAPHORE_NULL)
 114                 {
 115
 116                         assert(thread->joiner == NULL);
 117                         if (thread != self && (self == NULL || self->joiner != thread))
 118                         {
 119                                 int already_exited = (thread->detached & _PTHREAD_EXITED);
 120
 121                                 thread->death = death;
 122                                 thread->joiner = self;
 123                                 UNLOCK(thread->lock);
 124
 125                                 if (!already_exited)
 126                                 {
 127 #if __DARWIN_UNIX03
 128                                         /* Wait for it to signal... */
 129                                         pthread_cleanup_push(__posix_join_cleanup, (void *)thread);
 130                                         do {
 131                                                 res = __semwait_signal(death, 0, 0, 0, (int64_t)0, (int32_t)0);
 132                                         } while ((res < 0) && (errno == EINTR));
 133                                         pthread_cleanup_pop(0);
 134
 135 #else /* __DARWIN_UNIX03 */
 136                                         /* Wait for it to signal... */
 137                                         do {
 138                                                 PTHREAD_MACH_CALL(semaphore_wait(death), kern_res);
 139                                         } while (kern_res != KERN_SUCCESS);
 140 #endif /* __DARWIN_UNIX03 */
 141                                 }
 142
 143                                 LOCK(_pthread_list_lock);
 144                                 TAILQ_REMOVE(&__pthread_head, thread, plist);
 145 #if WQ_TRACE
 146                                 __kdebug_trace(0x9000010, thread, 0, 0, 16, 0);
 147 #endif
 148                                 UNLOCK(_pthread_list_lock);
 149                                 /* ... and wait for it to really be dead */
 150                                 while ((res = _pthread_reap_thread(thread,
 151                                                         thread->kernel_thread,
 152                                                         value_ptr, __unix_conforming)) == EAGAIN)
 153                                 {
 154                                         sched_yield();
 155                                 }
 156
 157                         } else {
 158                                 UNLOCK(thread->lock);
 159                                 res = EDEADLK;
 160                         }
 161                 } else {
 162                         UNLOCK(thread->lock);
 163                         res = EINVAL;
 164                 }
 165                 restore_sem_to_pool(death);
 166                 return res;
 167         } else {
 168                 /* new style */
 169
 170                 semaphore_t death = SEMAPHORE_NULL; /* in case we need it */
 171                 semaphore_t joinsem = SEMAPHORE_NULL;
 172
 173                 if (thread->joiner_notify == MACH_PORT_NULL)
 174                          death = new_sem_from_pool();
 175
 176                 LOCK(thread->lock);
 177                 if ((thread->detached & PTHREAD_CREATE_JOINABLE) &&
 178                         (thread->joiner == NULL))
 179                 {
 180                         assert(thread->kernel_thread == kthport);
 181                         if (thread != self && (self == NULL || self->joiner != thread))
 182                         {
 183                                 if (thread->joiner_notify == MACH_PORT_NULL) {
 184                                         if (death == SEMAPHORE_NULL)
 185                                                 LIBC_ABORT("thread %p: death == SEMAPHORE_NULL", thread);
 186                                         thread->joiner_notify = death;
 187                                         death = SEMAPHORE_NULL;
 188                                 }
 189                                 joinsem = thread->joiner_notify;
 190                                 thread->joiner = self;
 191                                 UNLOCK(thread->lock);
 192
 193                                 if (death != SEMAPHORE_NULL) {
 194                                         restore_sem_to_pool(death);
 195                                         death = SEMAPHORE_NULL;
 196                                 }
 197 #if __DARWIN_UNIX03
 198                                 /* Wait for it to signal... */
 199                                 pthread_cleanup_push(__posix_join_cleanup, (void *)thread);
 200                                 do {
 201                                         res = __semwait_signal(joinsem, 0, 0, 0, (int64_t)0, (int32_t)0);
 202                                 } while ((res < 0) && (errno == EINTR));
 203                                 pthread_cleanup_pop(0);
 204 #else /* __DARWIN_UNIX03 */
 205                                 /* Wait for it to signal... */
 206                                 do {
 207                                         PTHREAD_MACH_CALL(semaphore_wait(joinsem), kern_res);
 208                                 } while (kern_res != KERN_SUCCESS);
 209 #endif /* __DARWIN_UNIX03 */
 210
 211                                 restore_sem_to_pool(joinsem);
 212                                 res = _pthread_join_cleanup(thread, value_ptr, conforming);
 213                         } else {
 214                                 UNLOCK(thread->lock);
 215                                 res = EDEADLK;
 216                         }
 217                 } else {
 218                         UNLOCK(thread->lock);
 219                         res = EINVAL;
 220                 }
 221                 if (death != SEMAPHORE_NULL)
 222                         restore_sem_to_pool(death);
 223                 return res;
 224         }/* end of new style */
 225         }
 226         return ESRCH;
 227 }
 228
 229 int
 230 pthread_cond_wait(pthread_cond_t *cond,
 231                   pthread_mutex_t *mutex)
 232 {
 233         int conforming;
 234 #if __DARWIN_UNIX03
 235
 236         if (__unix_conforming == 0)
 237                 __unix_conforming = 1;
 238
 239 #ifdef VARIANT_CANCELABLE
 240         conforming = 1;
 241 #else /* !VARIANT_CANCELABLE */
 242         conforming = -1;
 243 #endif /* VARIANT_CANCELABLE */
 244 #else /* __DARWIN_UNIX03 */
 245         conforming = 0;
 246 #endif /* __DARWIN_UNIX03 */
 247         return (_pthread_cond_wait(cond, mutex, (struct timespec *)NULL, 0, conforming));
 248 }
 249
 250 int
 251 pthread_cond_timedwait(pthread_cond_t *cond,
 252                        pthread_mutex_t *mutex,
 253                        const struct timespec *abstime)
 254 {
 255         int conforming;
 256 #if __DARWIN_UNIX03
 257         if (__unix_conforming == 0)
 258                 __unix_conforming = 1;
 259
 260 #ifdef VARIANT_CANCELABLE
 261         conforming = 1;
 262 #else /* !VARIANT_CANCELABLE */
 263         conforming = -1;
 264 #endif /* VARIANT_CANCELABLE */
 265 #else /* __DARWIN_UNIX03 */
 266         conforming = 0;
 267 #endif /* __DARWIN_UNIX03 */
 268
 269         return (_pthread_cond_wait(cond, mutex, abstime, 0, conforming));
 270 }
 271
 272 int
 273 sigwait(const sigset_t * set, int * sig)
 274 {
 275 #if __DARWIN_UNIX03
 276         int err = 0;
 277
 278         if (__unix_conforming == 0)
 279                 __unix_conforming = 1;
 280
 281 #ifdef VARIANT_CANCELABLE
 282         _pthread_testcancel(pthread_self(), 1);
 283 #endif /* VARIANT_CANCELABLE */
 284
 285         if (__sigwait(set, sig) == -1) {
 286                 err = errno;
 287
 288                 /*
 289                  * EINTR that isn't a result of pthread_cancel()
 290                  * is translated to 0.
 291                  */
 292                 if (err == EINTR) {
 293                         err = 0;
 294                 }
 295         }
 296         return(err);
 297 #else /* __DARWIN_UNIX03 */
 298         if (__sigwait(set, sig) == -1) {
 299                 /*
 300                  * EINTR that isn't a result of pthread_cancel()
 301                  * is translated to 0.
 302                  */
 303                 if (errno != EINTR) {
 304                         return -1;
 305                 }
 306         }
 307
 308         return 0;
 309 #endif /* __DARWIN_UNIX03 */
 310 }