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73f7c32c | 1 | /* Copyright (C) 2002, 2003, 2004 Free Software Foundation, Inc. |
76a50749 UD |
2 | This file is part of the GNU C Library. |
3 | Contributed by Ulrich Drepper <drepper@redhat.com>, 2002. | |
4 | ||
5 | The GNU C Library is free software; you can redistribute it and/or | |
6 | modify it under the terms of the GNU Lesser General Public | |
7 | License as published by the Free Software Foundation; either | |
8 | version 2.1 of the License, or (at your option) any later version. | |
9 | ||
10 | The GNU C Library is distributed in the hope that it will be useful, | |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
13 | Lesser General Public License for more details. | |
14 | ||
15 | You should have received a copy of the GNU Lesser General Public | |
16 | License along with the GNU C Library; if not, write to the Free | |
17 | Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA | |
18 | 02111-1307 USA. */ | |
19 | ||
73f7c32c | 20 | #include <errno.h> |
bf293afe | 21 | #include <shlib-compat.h> |
76a50749 UD |
22 | #include "pthreadP.h" |
23 | ||
24 | ||
25 | int | |
83614008 | 26 | __pthread_cond_destroy (cond) |
76a50749 UD |
27 | pthread_cond_t *cond; |
28 | { | |
73f7c32c UD |
29 | /* Make sure we are alone. */ |
30 | lll_mutex_lock (cond->__data.__lock); | |
31 | ||
32 | if (cond->__data.__total_seq > cond->__data.__wakeup_seq) | |
33 | { | |
34 | /* If there are still some waiters which have not been | |
35 | woken up, this is an application bug. */ | |
36 | lll_mutex_unlock (cond->__data.__lock); | |
37 | return EBUSY; | |
38 | } | |
39 | ||
40 | /* Tell pthread_cond_*wait that this condvar is being destroyed. */ | |
41 | cond->__data.__total_seq = -1ULL; | |
42 | ||
43 | /* If there are waiters which have been already signalled or | |
44 | broadcasted, but still are using the pthread_cond_t structure, | |
45 | pthread_cond_destroy needs to wait for them. */ | |
46 | unsigned int nwaiters = cond->__data.__nwaiters; | |
0ecb606c JJ |
47 | |
48 | if (nwaiters >= (1 << COND_CLOCK_BITS)) | |
73f7c32c | 49 | { |
0ecb606c JJ |
50 | /* Wake everybody on the associated mutex in case there are |
51 | threads that have been requeued to it. | |
52 | Without this, pthread_cond_destroy could block potentially | |
53 | for a long time or forever, as it would depend on other | |
54 | thread's using the mutex. | |
55 | When all threads waiting on the mutex are woken up, pthread_cond_wait | |
56 | only waits for threads to acquire and release the internal | |
57 | condvar lock. */ | |
58 | if (cond->__data.__mutex != NULL | |
59 | && cond->__data.__mutex != (void *) ~0l) | |
60 | { | |
61 | pthread_mutex_t *mut = (pthread_mutex_t *) cond->__data.__mutex; | |
62 | lll_futex_wake (&mut->__data.__lock, INT_MAX); | |
63 | } | |
64 | ||
65 | do | |
66 | { | |
67 | lll_mutex_unlock (cond->__data.__lock); | |
73f7c32c | 68 | |
0ecb606c | 69 | lll_futex_wait (&cond->__data.__nwaiters, nwaiters); |
73f7c32c | 70 | |
0ecb606c | 71 | lll_mutex_lock (cond->__data.__lock); |
73f7c32c | 72 | |
0ecb606c JJ |
73 | nwaiters = cond->__data.__nwaiters; |
74 | } | |
75 | while (nwaiters >= (1 << COND_CLOCK_BITS)); | |
73f7c32c UD |
76 | } |
77 | ||
76a50749 UD |
78 | return 0; |
79 | } | |
bf293afe UD |
80 | versioned_symbol (libpthread, __pthread_cond_destroy, |
81 | pthread_cond_destroy, GLIBC_2_3_2); |