1 /* 2 * pthread_setcancelstate.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 (at) 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 int 42 pthread_setcancelstate (int state, int *oldstate) 43 /* 44 * ------------------------------------------------------ 45 * DOCPUBLIC 46 * This function atomically sets the calling thread's 47 * cancelability state to 'state' and returns the previous 48 * cancelability state at the location referenced by 49 * 'oldstate' 50 * 51 * PARAMETERS 52 * state, 53 * oldstate 54 * PTHREAD_CANCEL_ENABLE 55 * cancellation is enabled, 56 * 57 * PTHREAD_CANCEL_DISABLE 58 * cancellation is disabled 59 * 60 * 61 * DESCRIPTION 62 * This function atomically sets the calling thread's 63 * cancelability state to 'state' and returns the previous 64 * cancelability state at the location referenced by 65 * 'oldstate'. 66 * 67 * NOTES: 68 * 1) Use to disable cancellation around 'atomic' code that 69 * includes cancellation points 70 * 71 * COMPATIBILITY ADDITIONS 72 * If 'oldstate' is NULL then the previous state is not returned 73 * but the function still succeeds. (Solaris) 74 * 75 * RESULTS 76 * 0 successfully set cancelability type, 77 * EINVAL 'state' is invalid 78 * 79 * ------------------------------------------------------ 80 */ 81 { 82 ptw32_mcs_local_node_t stateLock; 83 int result = 0; 84 pthread_t self = pthread_self (); 85 ptw32_thread_t * sp = (ptw32_thread_t *) self.p; 86 87 if (sp == NULL 88 || (state != PTHREAD_CANCEL_ENABLE && state != PTHREAD_CANCEL_DISABLE)) 89 { 90 return EINVAL; 91 } 92 93 /* 94 * Lock for async-cancel safety. 95 */ 96 ptw32_mcs_lock_acquire (&sp->stateLock, &stateLock); 97 98 if (oldstate != NULL) 99 { 100 *oldstate = sp->cancelState; 101 } 102 103 sp->cancelState = state; 104 105 /* 106 * Check if there is a pending asynchronous cancel 107 */ 108 if (state == PTHREAD_CANCEL_ENABLE 109 && sp->cancelType == PTHREAD_CANCEL_ASYNCHRONOUS 110 && WaitForSingleObject (sp->cancelEvent, 0) == WAIT_OBJECT_0) 111 { 112 sp->state = PThreadStateCanceling; 113 sp->cancelState = PTHREAD_CANCEL_DISABLE; 114 ResetEvent (sp->cancelEvent); 115 ptw32_mcs_lock_release (&stateLock); 116 ptw32_throw (PTW32_EPS_CANCEL); 117 118 /* Never reached */ 119 } 120 121 ptw32_mcs_lock_release (&stateLock); 122 123 return (result); 124 125 } /* pthread_setcancelstate */ 126
