1 /*
2 * pthread_testcancel.c
3 *
4 * Description:
5 * POSIX thread functions related to thread cancellation.
6 *
7 * --------------------------------------------------------------------------
8 *
9 * Pthreads-win32 - POSIX Threads Library for Win32
10 * Copyright(C) 1998 John E. Bossom
11 * Copyright(C) 1999,2005 Pthreads-win32 contributors
12 *
13 * Contact Email: rpj@callisto.canberra.edu.au
14 *
15 * The current list of contributors is contained
16 * in the file CONTRIBUTORS included with the source
17 * code distribution. The list can also be seen at the
18 * following World Wide Web location:
19 * http://sources.redhat.com/pthreads-win32/contributors.html
20 *
21 * This library is free software; you can redistribute it and/or
22 * modify it under the terms of the GNU Lesser General Public
23 * License as published by the Free Software Foundation; either
24 * version 2 of the License, or (at your option) any later version.
25 *
26 * This library is distributed in the hope that it will be useful,
27 * but WITHOUT ANY WARRANTY; without even the implied warranty of
28 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
29 * Lesser General Public License for more details.
30 *
31 * You should have received a copy of the GNU Lesser General Public
32 * License along with this library in the file COPYING.LIB;
33 * if not, write to the Free Software Foundation, Inc.,
34 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
35 */
36
37 #include "pthread.h"
38 #include "implement.h"
39
40
41 void
pthread_testcancel(void)42 pthread_testcancel (void)
43 /*
44 * ------------------------------------------------------
45 * DOCPUBLIC
46 * This function creates a deferred cancellation point
47 * in the calling thread. The call has no effect if the
48 * current cancelability state is
49 * PTHREAD_CANCEL_DISABLE
50 *
51 * PARAMETERS
52 * N/A
53 *
54 *
55 * DESCRIPTION
56 * This function creates a deferred cancellation point
57 * in the calling thread. The call has no effect if the
58 * current cancelability state is
59 * PTHREAD_CANCEL_DISABLE
60 *
61 * NOTES:
62 * 1) Cancellation is asynchronous. Use pthread_join
63 * to wait for termination of thread if necessary
64 *
65 * RESULTS
66 * N/A
67 *
68 * ------------------------------------------------------
69 */
70 {
71 ptw32_mcs_local_node_t stateLock;
72 pthread_t self = pthread_self ();
73 ptw32_thread_t * sp = (ptw32_thread_t *) self.p;
74
75 if (sp == NULL)
76 {
77 return;
78 }
79
80 /*
81 * Pthread_cancel() will have set sp->state to PThreadStateCancelPending
82 * and set an event, so no need to enter kernel space if
83 * sp->state != PThreadStateCancelPending - that only slows us down.
84 */
85 if (sp->state != PThreadStateCancelPending)
86 {
87 return;
88 }
89
90 ptw32_mcs_lock_acquire (&sp->stateLock, &stateLock);
91
92 if (sp->cancelState != PTHREAD_CANCEL_DISABLE)
93 {
94 ResetEvent(sp->cancelEvent);
95 sp->state = PThreadStateCanceling;
96 sp->cancelState = PTHREAD_CANCEL_DISABLE;
97 ptw32_mcs_lock_release (&stateLock);
98 ptw32_throw (PTW32_EPS_CANCEL);
99 /* Never returns here */
100 }
101
102 ptw32_mcs_lock_release (&stateLock);
103 } /* pthread_testcancel */
104