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 * $DragonFly: src/lib/libthread_xu/thread/thr_sig.c,v 1.4 2005/03/29 19:26:20 joerg Exp $ 33 */ 34 35 #include <sys/param.h> 36 #include <sys/signalvar.h> 37 38 #include <machine/tls.h> 39 40 #include <signal.h> 41 #include <errno.h> 42 #include <fcntl.h> 43 #include <unistd.h> 44 #include <string.h> 45 #include <pthread.h> 46 47 #include "thr_private.h" 48 49 /* #define DEBUG_SIGNAL */ 50 #ifdef DEBUG_SIGNAL 51 #define DBG_MSG stdout_debug 52 #else 53 #define DBG_MSG(x...) 54 #endif 55 56 static void 57 sigcancel_handler(int sig, siginfo_t *info, ucontext_t *ucp) 58 { 59 struct pthread *curthread = tls_get_curthread(); 60 61 if (curthread->cancelflags & THR_CANCEL_AT_POINT) 62 pthread_testcancel(); 63 if (curthread->flags & THR_FLAGS_NEED_SUSPEND) { 64 __sys_sigprocmask(SIG_SETMASK, &ucp->uc_sigmask, NULL); 65 _thr_suspend_check(curthread); 66 } 67 } 68 69 void 70 _thr_suspend_check(struct pthread *curthread) 71 { 72 long cycle; 73 74 /* Async suspend. */ 75 _thr_signal_block(curthread); 76 THR_LOCK(curthread); 77 if ((curthread->flags & (THR_FLAGS_NEED_SUSPEND | THR_FLAGS_SUSPENDED)) 78 == THR_FLAGS_NEED_SUSPEND) { 79 curthread->flags |= THR_FLAGS_SUSPENDED; 80 while (curthread->flags & THR_FLAGS_NEED_SUSPEND) { 81 cycle = curthread->cycle; 82 THR_UNLOCK(curthread); 83 _thr_signal_unblock(curthread); 84 _thr_umtx_wait(&curthread->cycle, cycle, NULL, 0); 85 _thr_signal_block(curthread); 86 THR_LOCK(curthread); 87 } 88 curthread->flags &= ~THR_FLAGS_SUSPENDED; 89 } 90 THR_UNLOCK(curthread); 91 _thr_signal_unblock(curthread); 92 } 93 94 void 95 _thr_signal_init(void) 96 { 97 struct sigaction act; 98 99 /* Install cancel handler. */ 100 SIGEMPTYSET(act.sa_mask); 101 act.sa_flags = SA_SIGINFO | SA_RESTART; 102 act.sa_sigaction = (__siginfohandler_t *)&sigcancel_handler; 103 __sys_sigaction(SIGCANCEL, &act, NULL); 104 } 105 106 void 107 _thr_signal_deinit(void) 108 { 109 } 110 111 __weak_reference(_sigaction, sigaction); 112 113 int 114 _sigaction(int sig, const struct sigaction * act, struct sigaction * oact) 115 { 116 /* Check if the signal number is out of range: */ 117 if (sig < 1 || sig > _SIG_MAXSIG || sig == SIGCANCEL) { 118 /* Return an invalid argument: */ 119 errno = EINVAL; 120 return (-1); 121 } 122 123 return __sys_sigaction(sig, act, oact); 124 } 125 126 __weak_reference(_sigprocmask, sigprocmask); 127 128 int 129 _sigprocmask(int how, const sigset_t *set, sigset_t *oset) 130 { 131 const sigset_t *p = set; 132 sigset_t newset; 133 134 if (how != SIG_UNBLOCK) { 135 if (set != NULL) { 136 newset = *set; 137 SIGDELSET(newset, SIGCANCEL); 138 p = &newset; 139 } 140 } 141 return (__sys_sigprocmask(how, p, oset)); 142 } 143 144 __weak_reference(_pthread_sigmask, pthread_sigmask); 145 146 int 147 _pthread_sigmask(int how, const sigset_t *set, sigset_t *oset) 148 { 149 if (_sigprocmask(how, set, oset)) 150 return (errno); 151 return (0); 152 } 153 154 __weak_reference(_sigsuspend, sigsuspend); 155 156 int 157 _sigsuspend(const sigset_t * set) 158 { 159 struct pthread *curthread = tls_get_curthread(); 160 sigset_t newset; 161 const sigset_t *pset; 162 int oldcancel; 163 int ret; 164 165 if (SIGISMEMBER(*set, SIGCANCEL)) { 166 newset = *set; 167 SIGDELSET(newset, SIGCANCEL); 168 pset = &newset; 169 } else 170 pset = set; 171 172 oldcancel = _thr_cancel_enter(curthread); 173 ret = __sys_sigsuspend(pset); 174 _thr_cancel_leave(curthread, oldcancel); 175 176 return (ret); 177 } 178 179 __weak_reference(__sigwait, sigwait); 180 __weak_reference(__sigtimedwait, sigtimedwait); 181 __weak_reference(__sigwaitinfo, sigwaitinfo); 182 183 int 184 __sigtimedwait(const sigset_t *set, siginfo_t *info, 185 const struct timespec * timeout) 186 { 187 struct pthread *curthread = tls_get_curthread(); 188 sigset_t newset; 189 const sigset_t *pset; 190 int oldcancel; 191 int ret; 192 193 if (SIGISMEMBER(*set, SIGCANCEL)) { 194 newset = *set; 195 SIGDELSET(newset, SIGCANCEL); 196 pset = &newset; 197 } else 198 pset = set; 199 oldcancel = _thr_cancel_enter(curthread); 200 ret = __sys_sigtimedwait(pset, info, timeout); 201 _thr_cancel_leave(curthread, oldcancel); 202 return (ret); 203 } 204 205 int 206 __sigwaitinfo(const sigset_t *set, siginfo_t *info) 207 { 208 struct pthread *curthread = tls_get_curthread(); 209 sigset_t newset; 210 const sigset_t *pset; 211 int oldcancel; 212 int ret; 213 214 if (SIGISMEMBER(*set, SIGCANCEL)) { 215 newset = *set; 216 SIGDELSET(newset, SIGCANCEL); 217 pset = &newset; 218 } else 219 pset = set; 220 221 oldcancel = _thr_cancel_enter(curthread); 222 ret = __sys_sigwaitinfo(pset, info); 223 _thr_cancel_leave(curthread, oldcancel); 224 return (ret); 225 } 226 227 int 228 __sigwait(const sigset_t *set, int *sig) 229 { 230 int s; 231 232 s = __sigwaitinfo(set, NULL); 233 if (s > 0) { 234 *sig = s; 235 return (0); 236 } 237 return (errno); 238 } 239