1 /* 2 * Copyright (c) 2003 Jeffrey Roberson <jeff@freebsd.org> 3 * Copyright (c) 2003 Jonathan Mini <mini@freebsd.org> 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice unmodified, this list of conditions, and the following 11 * disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 * 27 * $FreeBSD$ 28 */ 29 30 #include <sys/param.h> 31 #include <sys/types.h> 32 #include <sys/signalvar.h> 33 #include <signal.h> 34 #include <fcntl.h> 35 #include <unistd.h> 36 #include <setjmp.h> 37 #include <errno.h> 38 #include <pthread.h> 39 #include <stdlib.h> 40 41 #include "thr_private.h" 42 43 /* #define DEBUG_SIGNAL */ 44 #ifdef DEBUG_SIGNAL 45 #define DBG_MSG stdout_debug 46 #else 47 #define DBG_MSG(x...) 48 #endif 49 50 __weak_reference(_sigprocmask, sigprocmask); 51 52 int 53 _sigprocmask(int how, const sigset_t *set, sigset_t *oset) 54 { 55 sigset_t new; 56 57 /* 58 * Make sure applications can't unblock our synchronization 59 * signal. We always want to take this with sigwait(). 60 */ 61 if (set != NULL) { 62 new = *set; 63 switch (how) { 64 case SIG_BLOCK: 65 case SIG_SETMASK: 66 SIGADDSET(new, SIGTHR); 67 break; 68 case SIG_UNBLOCK: 69 SIGDELSET(new, SIGTHR); 70 break; 71 default: 72 break; 73 } 74 set = &new; 75 } 76 77 return (__sys_sigprocmask(how, set, oset)); 78 } 79 80 __weak_reference(_pthread_sigmask, pthread_sigmask); 81 82 int 83 _pthread_sigmask(int how, const sigset_t *set, sigset_t *oset) 84 { 85 int error; 86 87 /* 88 * This always sets the mask on the current thread. 89 */ 90 error = sigprocmask(how, set, oset); 91 92 /* 93 * pthread_sigmask returns errno or success while sigprocmask returns 94 * -1 and sets errno. 95 */ 96 if (error == -1) 97 error = errno; 98 99 return (error); 100 } 101 102 103 __weak_reference(_pthread_kill, pthread_kill); 104 105 int 106 _pthread_kill(pthread_t pthread, int sig) 107 { 108 109 if (_thread_initial == NULL) 110 _thread_init(); 111 return (thr_kill(pthread->thr_id, sig)); 112 } 113 114 /* 115 * User thread signal handler wrapper. 116 */ 117 void 118 _thread_sig_wrapper(int sig, siginfo_t *info, void *context) 119 { 120 struct pthread_state_data psd; 121 struct sigaction *actp; 122 __siginfohandler_t *handler; 123 struct umtx *up; 124 spinlock_t *sp; 125 126 /* 127 * Do a little cleanup handling for those threads in 128 * queues before calling the signal handler. Signals 129 * for these threads are temporarily blocked until 130 * after cleanup handling. 131 */ 132 switch (curthread->state) { 133 case PS_BARRIER_WAIT: 134 /* 135 * XXX - The thread has reached the barrier. We can't 136 * "back it away" from the barrier. 137 */ 138 _thread_critical_enter(curthread); 139 break; 140 case PS_COND_WAIT: 141 /* 142 * Cache the address, since it will not be available 143 * after it has been backed out. 144 */ 145 up = &curthread->data.cond->c_lock; 146 147 UMTX_LOCK(up); 148 _thread_critical_enter(curthread); 149 _cond_wait_backout(curthread); 150 UMTX_UNLOCK(up); 151 break; 152 case PS_MUTEX_WAIT: 153 /* 154 * Cache the address, since it will not be available 155 * after it has been backed out. 156 */ 157 sp = &curthread->data.mutex->lock; 158 159 _SPINLOCK(sp); 160 _thread_critical_enter(curthread); 161 _mutex_lock_backout(curthread); 162 _SPINUNLOCK(sp); 163 break; 164 default: 165 /* 166 * We need to lock the thread to read it's flags. 167 */ 168 _thread_critical_enter(curthread); 169 break; 170 } 171 172 /* 173 * We save the flags now so that any modifications done as part 174 * of the backout are reflected when the flags are restored. 175 */ 176 psd.psd_flags = curthread->flags; 177 178 PTHREAD_SET_STATE(curthread, PS_RUNNING); 179 _thread_critical_exit(curthread); 180 actp = proc_sigact_sigaction(sig); 181 handler = (__siginfohandler_t *)actp->sa_handler; 182 handler(sig, info, (ucontext_t *)context); 183 184 /* Restore the thread's flags, and make it runnable */ 185 _thread_critical_enter(curthread); 186 curthread->flags = psd.psd_flags; 187 PTHREAD_SET_STATE(curthread, PS_RUNNING); 188 _thread_critical_exit(curthread); 189 } 190