blob: 681bb4404cd0b6af1a0014d3195ee122c833ed86 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
|
/*
* pthread_spin_trylock.c
*
* Description:
* This translation unit implements spin lock primitives.
*
* --------------------------------------------------------------------------
*
* Pthreads-win32 - POSIX Threads Library for Win32
* Copyright(C) 1998 John E. Bossom
* Copyright(C) 1999,2004 Pthreads-win32 contributors
*
* Contact Email: rpj@callisto.canberra.edu.au
*
* The current list of contributors is contained
* in the file CONTRIBUTORS included with the source
* code distribution. The list can also be seen at the
* following World Wide Web location:
* http://sources.redhat.com/pthreads-win32/contributors.html
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library in the file COPYING.LIB;
* if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
*/
#include "pthread.h"
#include "implement.h"
int
pthread_spin_trylock (pthread_spinlock_t * lock)
{
register pthread_spinlock_t s;
if (NULL == lock || NULL == *lock)
{
return (EINVAL);
}
if (*lock == PTHREAD_SPINLOCK_INITIALIZER)
{
int result;
if ((result = ptw32_spinlock_check_need_init (lock)) != 0)
{
return (result);
}
}
s = *lock;
switch ((long)
PTW32_INTERLOCKED_COMPARE_EXCHANGE ((PTW32_INTERLOCKED_LPLONG) &
(s->interlock),
(PTW32_INTERLOCKED_LONG)
PTW32_SPIN_LOCKED,
(PTW32_INTERLOCKED_LONG)
PTW32_SPIN_UNLOCKED))
{
case PTW32_SPIN_UNLOCKED:
return 0;
case PTW32_SPIN_LOCKED:
return EBUSY;
case PTW32_SPIN_USE_MUTEX:
return pthread_mutex_trylock (&(s->u.mutex));
}
return EINVAL;
}
|