1 /* 2 * Copyright (c) 1995-1998 John Birrell <jb@cimlogic.com.au> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by John Birrell. 16 * 4. Neither the name of the author nor the names of any co-contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * $FreeBSD$ 33 */ 34 35 #include <sys/param.h> 36 #include <sys/types.h> 37 #include <sys/signalvar.h> 38 #include <signal.h> 39 #include <errno.h> 40 #include <fcntl.h> 41 #include <unistd.h> 42 #include <string.h> 43 #include <pthread.h> 44 45 #include "thr_private.h" 46 47 /* #define DEBUG_SIGNAL */ 48 #ifdef DEBUG_SIGNAL 49 #define DBG_MSG stdout_debug 50 #else 51 #define DBG_MSG(x...) 52 #endif 53 54 static void 55 sigcancel_handler(int sig, siginfo_t *info, ucontext_t *ucp) 56 { 57 struct pthread *curthread = _get_curthread(); 58 59 if (curthread->cancelflags & THR_CANCEL_AT_POINT) 60 pthread_testcancel(); 61 if (curthread->flags & THR_FLAGS_NEED_SUSPEND) { 62 __sys_sigprocmask(SIG_SETMASK, &ucp->uc_sigmask, NULL); 63 _thr_suspend_check(curthread); 64 } 65 } 66 67 void 68 _thr_suspend_check(struct pthread *curthread) 69 { 70 long cycle; 71 72 /* Async suspend. */ 73 _thr_signal_block(curthread); 74 THR_LOCK(curthread); 75 if ((curthread->flags & (THR_FLAGS_NEED_SUSPEND | THR_FLAGS_SUSPENDED)) 76 == THR_FLAGS_NEED_SUSPEND) { 77 curthread->flags |= THR_FLAGS_SUSPENDED; 78 while (curthread->flags & THR_FLAGS_NEED_SUSPEND) { 79 cycle = curthread->cycle; 80 THR_UNLOCK(curthread); 81 _thr_signal_unblock(curthread); 82 _thr_umtx_wait(&curthread->cycle, cycle, NULL); 83 _thr_signal_block(curthread); 84 THR_LOCK(curthread); 85 } 86 curthread->flags &= ~THR_FLAGS_SUSPENDED; 87 } 88 THR_UNLOCK(curthread); 89 _thr_signal_unblock(curthread); 90 } 91 92 void 93 _thr_signal_init(void) 94 { 95 struct sigaction act; 96 97 /* Install cancel handler. */ 98 SIGEMPTYSET(act.sa_mask); 99 act.sa_flags = SA_SIGINFO | SA_RESTART; 100 act.sa_sigaction = (__siginfohandler_t *)&sigcancel_handler; 101 __sys_sigaction(SIGCANCEL, &act, NULL); 102 } 103 104 void 105 _thr_signal_deinit(void) 106 { 107 } 108 109 __weak_reference(_sigaction, sigaction); 110 111 int 112 _sigaction(int sig, const struct sigaction * act, struct sigaction * oact) 113 { 114 /* Check if the signal number is out of range: */ 115 if (sig < 1 || sig > _SIG_MAXSIG || sig == SIGCANCEL) { 116 /* Return an invalid argument: */ 117 errno = EINVAL; 118 return (-1); 119 } 120 121 return __sys_sigaction(sig, act, oact); 122 } 123 124 __weak_reference(_sigprocmask, sigprocmask); 125 126 int 127 _sigprocmask(int how, const sigset_t *set, sigset_t *oset) 128 { 129 const sigset_t *p = set; 130 sigset_t newset; 131 132 if (how != SIG_UNBLOCK) { 133 if (set != NULL) { 134 newset = *set; 135 SIGDELSET(newset, SIGCANCEL); 136 p = &newset; 137 } 138 } 139 return (__sys_sigprocmask(how, p, oset)); 140 } 141 142 __weak_reference(_pthread_sigmask, pthread_sigmask); 143 144 int 145 _pthread_sigmask(int how, const sigset_t *set, sigset_t *oset) 146 { 147 if (_sigprocmask(how, set, oset)) 148 return (errno); 149 return (0); 150 } 151 152 __weak_reference(_sigsuspend, sigsuspend); 153 154 int 155 _sigsuspend(const sigset_t * set) 156 { 157 struct pthread *curthread = _get_curthread(); 158 sigset_t newset; 159 const sigset_t *pset; 160 int oldcancel; 161 int ret; 162 163 if (SIGISMEMBER(*set, SIGCANCEL)) { 164 newset = *set; 165 SIGDELSET(newset, SIGCANCEL); 166 pset = &newset; 167 } else 168 pset = set; 169 170 oldcancel = _thr_cancel_enter(curthread); 171 ret = __sys_sigsuspend(pset); 172 _thr_cancel_leave(curthread, oldcancel); 173 174 return (ret); 175 } 176 177 __weak_reference(__sigwait, sigwait); 178 __weak_reference(__sigtimedwait, sigtimedwait); 179 __weak_reference(__sigwaitinfo, sigwaitinfo); 180 181 int 182 __sigtimedwait(const sigset_t *set, siginfo_t *info, 183 const struct timespec * timeout) 184 { 185 struct pthread *curthread = _get_curthread(); 186 sigset_t newset; 187 const sigset_t *pset; 188 int oldcancel; 189 int ret; 190 191 if (SIGISMEMBER(*set, SIGCANCEL)) { 192 newset = *set; 193 SIGDELSET(newset, SIGCANCEL); 194 pset = &newset; 195 } else 196 pset = set; 197 oldcancel = _thr_cancel_enter(curthread); 198 ret = __sys_sigtimedwait(pset, info, timeout); 199 _thr_cancel_leave(curthread, oldcancel); 200 return (ret); 201 } 202 203 int 204 __sigwaitinfo(const sigset_t *set, siginfo_t *info) 205 { 206 struct pthread *curthread = _get_curthread(); 207 sigset_t newset; 208 const sigset_t *pset; 209 int oldcancel; 210 int ret; 211 212 if (SIGISMEMBER(*set, SIGCANCEL)) { 213 newset = *set; 214 SIGDELSET(newset, SIGCANCEL); 215 pset = &newset; 216 } else 217 pset = set; 218 219 oldcancel = _thr_cancel_enter(curthread); 220 ret = __sys_sigwaitinfo(pset, info); 221 _thr_cancel_leave(curthread, oldcancel); 222 return (ret); 223 } 224 225 int 226 __sigwait(const sigset_t *set, int *sig) 227 { 228 struct pthread *curthread = _get_curthread(); 229 sigset_t newset; 230 const sigset_t *pset; 231 int oldcancel; 232 int ret; 233 234 if (SIGISMEMBER(*set, SIGCANCEL)) { 235 newset = *set; 236 SIGDELSET(newset, SIGCANCEL); 237 pset = &newset; 238 } else 239 pset = set; 240 241 oldcancel = _thr_cancel_enter(curthread); 242 ret = __sys_sigwait(pset, sig); 243 _thr_cancel_leave(curthread, oldcancel); 244 return (ret); 245 } 246