1 /* 2 * Copyright (c) 2005, David Xu <davidxu@freebsd.org> 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 unmodified, this list of conditions, and the following 10 * disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 * 26 * $FreeBSD$ 27 */ 28 29 #include <sys/param.h> 30 #include <sys/types.h> 31 #include <sys/signalvar.h> 32 #include <signal.h> 33 #include <errno.h> 34 #include <fcntl.h> 35 #include <unistd.h> 36 #include <string.h> 37 #include <pthread.h> 38 39 #include "thr_private.h" 40 41 /* #define DEBUG_SIGNAL */ 42 #ifdef DEBUG_SIGNAL 43 #define DBG_MSG stdout_debug 44 #else 45 #define DBG_MSG(x...) 46 #endif 47 48 static void 49 sigcancel_handler(int sig, siginfo_t *info, ucontext_t *ucp) 50 { 51 struct pthread *curthread = _get_curthread(); 52 53 if (curthread->cancelflags & THR_CANCEL_AT_POINT) 54 pthread_testcancel(); 55 if (curthread->flags & THR_FLAGS_NEED_SUSPEND) { 56 __sys_sigprocmask(SIG_SETMASK, &ucp->uc_sigmask, NULL); 57 _thr_suspend_check(curthread); 58 } 59 } 60 61 void 62 _thr_suspend_check(struct pthread *curthread) 63 { 64 long cycle; 65 66 /* Async suspend. */ 67 _thr_signal_block(curthread); 68 THR_LOCK(curthread); 69 if ((curthread->flags & (THR_FLAGS_NEED_SUSPEND | THR_FLAGS_SUSPENDED)) 70 == THR_FLAGS_NEED_SUSPEND) { 71 curthread->flags |= THR_FLAGS_SUSPENDED; 72 while (curthread->flags & THR_FLAGS_NEED_SUSPEND) { 73 cycle = curthread->cycle; 74 THR_UNLOCK(curthread); 75 _thr_signal_unblock(curthread); 76 _thr_umtx_wait(&curthread->cycle, cycle, NULL); 77 _thr_signal_block(curthread); 78 THR_LOCK(curthread); 79 } 80 curthread->flags &= ~THR_FLAGS_SUSPENDED; 81 } 82 THR_UNLOCK(curthread); 83 _thr_signal_unblock(curthread); 84 } 85 86 void 87 _thr_signal_init(void) 88 { 89 struct sigaction act; 90 91 /* Install cancel handler. */ 92 SIGEMPTYSET(act.sa_mask); 93 act.sa_flags = SA_SIGINFO | SA_RESTART; 94 act.sa_sigaction = (__siginfohandler_t *)&sigcancel_handler; 95 __sys_sigaction(SIGCANCEL, &act, NULL); 96 } 97 98 void 99 _thr_signal_deinit(void) 100 { 101 } 102 103 __weak_reference(_sigaction, sigaction); 104 105 int 106 _sigaction(int sig, const struct sigaction * act, struct sigaction * oact) 107 { 108 /* Check if the signal number is out of range: */ 109 if (sig < 1 || sig > _SIG_MAXSIG || sig == SIGCANCEL) { 110 /* Return an invalid argument: */ 111 errno = EINVAL; 112 return (-1); 113 } 114 115 return __sys_sigaction(sig, act, oact); 116 } 117 118 __weak_reference(_sigprocmask, sigprocmask); 119 120 int 121 _sigprocmask(int how, const sigset_t *set, sigset_t *oset) 122 { 123 const sigset_t *p = set; 124 sigset_t newset; 125 126 if (how != SIG_UNBLOCK) { 127 if (set != NULL) { 128 newset = *set; 129 SIGDELSET(newset, SIGCANCEL); 130 p = &newset; 131 } 132 } 133 return (__sys_sigprocmask(how, p, oset)); 134 } 135 136 __weak_reference(_pthread_sigmask, pthread_sigmask); 137 138 int 139 _pthread_sigmask(int how, const sigset_t *set, sigset_t *oset) 140 { 141 if (_sigprocmask(how, set, oset)) 142 return (errno); 143 return (0); 144 } 145 146 __weak_reference(_sigsuspend, sigsuspend); 147 148 int 149 _sigsuspend(const sigset_t * set) 150 { 151 struct pthread *curthread = _get_curthread(); 152 sigset_t newset; 153 const sigset_t *pset; 154 int oldcancel; 155 int ret; 156 157 if (SIGISMEMBER(*set, SIGCANCEL)) { 158 newset = *set; 159 SIGDELSET(newset, SIGCANCEL); 160 pset = &newset; 161 } else 162 pset = set; 163 164 oldcancel = _thr_cancel_enter(curthread); 165 ret = __sys_sigsuspend(pset); 166 _thr_cancel_leave(curthread, oldcancel); 167 168 return (ret); 169 } 170 171 __weak_reference(__sigwait, sigwait); 172 __weak_reference(__sigtimedwait, sigtimedwait); 173 __weak_reference(__sigwaitinfo, sigwaitinfo); 174 175 int 176 __sigtimedwait(const sigset_t *set, siginfo_t *info, 177 const struct timespec * timeout) 178 { 179 struct pthread *curthread = _get_curthread(); 180 sigset_t newset; 181 const sigset_t *pset; 182 int oldcancel; 183 int ret; 184 185 if (SIGISMEMBER(*set, SIGCANCEL)) { 186 newset = *set; 187 SIGDELSET(newset, SIGCANCEL); 188 pset = &newset; 189 } else 190 pset = set; 191 oldcancel = _thr_cancel_enter(curthread); 192 ret = __sys_sigtimedwait(pset, info, timeout); 193 _thr_cancel_leave(curthread, oldcancel); 194 return (ret); 195 } 196 197 int 198 __sigwaitinfo(const sigset_t *set, siginfo_t *info) 199 { 200 struct pthread *curthread = _get_curthread(); 201 sigset_t newset; 202 const sigset_t *pset; 203 int oldcancel; 204 int ret; 205 206 if (SIGISMEMBER(*set, SIGCANCEL)) { 207 newset = *set; 208 SIGDELSET(newset, SIGCANCEL); 209 pset = &newset; 210 } else 211 pset = set; 212 213 oldcancel = _thr_cancel_enter(curthread); 214 ret = __sys_sigwaitinfo(pset, info); 215 _thr_cancel_leave(curthread, oldcancel); 216 return (ret); 217 } 218 219 int 220 __sigwait(const sigset_t *set, int *sig) 221 { 222 struct pthread *curthread = _get_curthread(); 223 sigset_t newset; 224 const sigset_t *pset; 225 int oldcancel; 226 int ret; 227 228 if (SIGISMEMBER(*set, SIGCANCEL)) { 229 newset = *set; 230 SIGDELSET(newset, SIGCANCEL); 231 pset = &newset; 232 } else 233 pset = set; 234 235 oldcancel = _thr_cancel_enter(curthread); 236 ret = __sys_sigwait(pset, sig); 237 _thr_cancel_leave(curthread, oldcancel); 238 return (ret); 239 } 240