17c478bd9Sstevel@tonic-gate /* 27c478bd9Sstevel@tonic-gate * CDDL HEADER START 37c478bd9Sstevel@tonic-gate * 47c478bd9Sstevel@tonic-gate * The contents of this file are subject to the terms of the 534709573Sraf * Common Development and Distribution License (the "License"). 634709573Sraf * You may not use this file except in compliance with the License. 77c478bd9Sstevel@tonic-gate * 87c478bd9Sstevel@tonic-gate * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 97c478bd9Sstevel@tonic-gate * or http://www.opensolaris.org/os/licensing. 107c478bd9Sstevel@tonic-gate * See the License for the specific language governing permissions 117c478bd9Sstevel@tonic-gate * and limitations under the License. 127c478bd9Sstevel@tonic-gate * 137c478bd9Sstevel@tonic-gate * When distributing Covered Code, include this CDDL HEADER in each 147c478bd9Sstevel@tonic-gate * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 157c478bd9Sstevel@tonic-gate * If applicable, add the following below this CDDL HEADER, with the 167c478bd9Sstevel@tonic-gate * fields enclosed by brackets "[]" replaced with your own identifying 177c478bd9Sstevel@tonic-gate * information: Portions Copyright [yyyy] [name of copyright owner] 187c478bd9Sstevel@tonic-gate * 197c478bd9Sstevel@tonic-gate * CDDL HEADER END 207c478bd9Sstevel@tonic-gate */ 210293487cSraf 227c478bd9Sstevel@tonic-gate /* 23ae115bc7Smrj * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 247c478bd9Sstevel@tonic-gate * Use is subject to license terms. 257c478bd9Sstevel@tonic-gate */ 267c478bd9Sstevel@tonic-gate 277c478bd9Sstevel@tonic-gate #pragma ident "%Z%%M% %I% %E% SMI" 287c478bd9Sstevel@tonic-gate 297c478bd9Sstevel@tonic-gate #include "lint.h" 307c478bd9Sstevel@tonic-gate #include "thr_uberdata.h" 31f841f6adSraf #include "asyncio.h" 327c478bd9Sstevel@tonic-gate #include <signal.h> 337c478bd9Sstevel@tonic-gate #include <siginfo.h> 347c478bd9Sstevel@tonic-gate #include <ucontext.h> 357c478bd9Sstevel@tonic-gate #include <sys/systm.h> 367c478bd9Sstevel@tonic-gate 377c478bd9Sstevel@tonic-gate const sigset_t maskset = {MASKSET0, MASKSET1, 0, 0}; /* maskable signals */ 387c478bd9Sstevel@tonic-gate 397c478bd9Sstevel@tonic-gate /* 407c478bd9Sstevel@tonic-gate * Return true if the valid signal bits in both sets are the same. 417c478bd9Sstevel@tonic-gate */ 427c478bd9Sstevel@tonic-gate int 437c478bd9Sstevel@tonic-gate sigequalset(const sigset_t *s1, const sigset_t *s2) 447c478bd9Sstevel@tonic-gate { 457c478bd9Sstevel@tonic-gate /* 467c478bd9Sstevel@tonic-gate * We only test valid signal bits, not rubbish following MAXSIG 477c478bd9Sstevel@tonic-gate * (for speed). Algorithm: 487c478bd9Sstevel@tonic-gate * if (s1 & fillset) == (s2 & fillset) then (s1 ^ s2) & fillset == 0 497c478bd9Sstevel@tonic-gate */ 507c478bd9Sstevel@tonic-gate return (!((s1->__sigbits[0] ^ s2->__sigbits[0]) | 517c478bd9Sstevel@tonic-gate ((s1->__sigbits[1] ^ s2->__sigbits[1]) & FILLSET1))); 527c478bd9Sstevel@tonic-gate } 537c478bd9Sstevel@tonic-gate 547c478bd9Sstevel@tonic-gate /* 557c478bd9Sstevel@tonic-gate * Common code for calling the user-specified signal handler. 567c478bd9Sstevel@tonic-gate */ 577c478bd9Sstevel@tonic-gate void 587c478bd9Sstevel@tonic-gate call_user_handler(int sig, siginfo_t *sip, ucontext_t *ucp) 597c478bd9Sstevel@tonic-gate { 607c478bd9Sstevel@tonic-gate ulwp_t *self = curthread; 617c478bd9Sstevel@tonic-gate uberdata_t *udp = self->ul_uberdata; 627c478bd9Sstevel@tonic-gate struct sigaction uact; 637c478bd9Sstevel@tonic-gate volatile struct sigaction *sap; 647c478bd9Sstevel@tonic-gate 657c478bd9Sstevel@tonic-gate /* 667c478bd9Sstevel@tonic-gate * If we are taking a signal while parked or about to be parked 677c478bd9Sstevel@tonic-gate * on __lwp_park() then remove ourself from the sleep queue so 687c478bd9Sstevel@tonic-gate * that we can grab locks. The code in mutex_lock_queue() and 697c478bd9Sstevel@tonic-gate * cond_wait_common() will detect this and deal with it when 707c478bd9Sstevel@tonic-gate * __lwp_park() returns. 717c478bd9Sstevel@tonic-gate */ 727c478bd9Sstevel@tonic-gate unsleep_self(); 737c478bd9Sstevel@tonic-gate set_parking_flag(self, 0); 747c478bd9Sstevel@tonic-gate 757c478bd9Sstevel@tonic-gate if (__td_event_report(self, TD_CATCHSIG, udp)) { 767c478bd9Sstevel@tonic-gate self->ul_td_evbuf.eventnum = TD_CATCHSIG; 777c478bd9Sstevel@tonic-gate self->ul_td_evbuf.eventdata = (void *)(intptr_t)sig; 787c478bd9Sstevel@tonic-gate tdb_event(TD_CATCHSIG, udp); 797c478bd9Sstevel@tonic-gate } 807c478bd9Sstevel@tonic-gate 817c478bd9Sstevel@tonic-gate /* 827c478bd9Sstevel@tonic-gate * Get a self-consistent set of flags, handler, and mask 837c478bd9Sstevel@tonic-gate * while holding the sig's sig_lock for the least possible time. 847c478bd9Sstevel@tonic-gate * We must acquire the sig's sig_lock because some thread running 857c478bd9Sstevel@tonic-gate * in sigaction() might be establishing a new signal handler. 86*41efec22Sraf * The code in sigaction() acquires the writer lock; here 87*41efec22Sraf * we acquire the readers lock to ehance concurrency in the 88*41efec22Sraf * face of heavy signal traffic, such as generated by java. 897c478bd9Sstevel@tonic-gate * 907c478bd9Sstevel@tonic-gate * Locking exceptions: 917c478bd9Sstevel@tonic-gate * No locking for a child of vfork(). 927c478bd9Sstevel@tonic-gate * If the signal is SIGPROF with an si_code of PROF_SIG, 937c478bd9Sstevel@tonic-gate * then we assume that this signal was generated by 947c478bd9Sstevel@tonic-gate * setitimer(ITIMER_REALPROF) set up by the dbx collector. 957c478bd9Sstevel@tonic-gate * If the signal is SIGEMT with an si_code of EMT_CPCOVF, 967c478bd9Sstevel@tonic-gate * then we assume that the signal was generated by 977c478bd9Sstevel@tonic-gate * a hardware performance counter overflow. 987c478bd9Sstevel@tonic-gate * In these cases, assume that we need no locking. It is the 997c478bd9Sstevel@tonic-gate * monitoring program's responsibility to ensure correctness. 1007c478bd9Sstevel@tonic-gate */ 1017c478bd9Sstevel@tonic-gate sap = &udp->siguaction[sig].sig_uaction; 1027c478bd9Sstevel@tonic-gate if (self->ul_vfork || 1037c478bd9Sstevel@tonic-gate (sip != NULL && 1047c478bd9Sstevel@tonic-gate ((sig == SIGPROF && sip->si_code == PROF_SIG) || 1057c478bd9Sstevel@tonic-gate (sig == SIGEMT && sip->si_code == EMT_CPCOVF)))) { 1067c478bd9Sstevel@tonic-gate /* we wish this assignment could be atomic */ 1070293487cSraf (void) _private_memcpy(&uact, (void *)sap, sizeof (uact)); 1087c478bd9Sstevel@tonic-gate } else { 109*41efec22Sraf rwlock_t *rwlp = &udp->siguaction[sig].sig_lock; 110*41efec22Sraf lrw_rdlock(rwlp); 1110293487cSraf (void) _private_memcpy(&uact, (void *)sap, sizeof (uact)); 1127c478bd9Sstevel@tonic-gate if (sig == SIGCANCEL && (sap->sa_flags & SA_RESETHAND)) 1137c478bd9Sstevel@tonic-gate sap->sa_sigaction = SIG_DFL; 114*41efec22Sraf lrw_unlock(rwlp); 1157c478bd9Sstevel@tonic-gate } 1167c478bd9Sstevel@tonic-gate 1177c478bd9Sstevel@tonic-gate /* 1187c478bd9Sstevel@tonic-gate * Set the proper signal mask and call the user's signal handler. 1197c478bd9Sstevel@tonic-gate * (We overrode the user-requested signal mask with maskset 1207c478bd9Sstevel@tonic-gate * so we currently have all blockable signals blocked.) 1217c478bd9Sstevel@tonic-gate * 1227c478bd9Sstevel@tonic-gate * We would like to ASSERT() that the signal is not a member of the 1237c478bd9Sstevel@tonic-gate * signal mask at the previous level (ucp->uc_sigmask) or the specified 1247c478bd9Sstevel@tonic-gate * signal mask for sigsuspend() or pollsys() (self->ul_tmpmask) but 1257c478bd9Sstevel@tonic-gate * /proc can override this via PCSSIG, so we don't bother. 1267c478bd9Sstevel@tonic-gate * 1277c478bd9Sstevel@tonic-gate * We would also like to ASSERT() that the signal mask at the previous 1287c478bd9Sstevel@tonic-gate * level equals self->ul_sigmask (maskset for sigsuspend() / pollsys()), 1297c478bd9Sstevel@tonic-gate * but /proc can change the thread's signal mask via PCSHOLD, so we 1307c478bd9Sstevel@tonic-gate * don't bother with that either. 1317c478bd9Sstevel@tonic-gate */ 1327c478bd9Sstevel@tonic-gate ASSERT(ucp->uc_flags & UC_SIGMASK); 1337c478bd9Sstevel@tonic-gate if (self->ul_sigsuspend) { 1347c478bd9Sstevel@tonic-gate ucp->uc_sigmask = self->ul_sigmask; 1357c478bd9Sstevel@tonic-gate self->ul_sigsuspend = 0; 1367c478bd9Sstevel@tonic-gate /* the sigsuspend() or pollsys() signal mask */ 1377c478bd9Sstevel@tonic-gate sigorset(&uact.sa_mask, &self->ul_tmpmask); 1387c478bd9Sstevel@tonic-gate } else { 1397c478bd9Sstevel@tonic-gate /* the signal mask at the previous level */ 1407c478bd9Sstevel@tonic-gate sigorset(&uact.sa_mask, &ucp->uc_sigmask); 1417c478bd9Sstevel@tonic-gate } 1427c478bd9Sstevel@tonic-gate if (!(uact.sa_flags & SA_NODEFER)) /* add current signal */ 1437c478bd9Sstevel@tonic-gate (void) _private_sigaddset(&uact.sa_mask, sig); 1447c478bd9Sstevel@tonic-gate self->ul_sigmask = uact.sa_mask; 1457c478bd9Sstevel@tonic-gate self->ul_siglink = ucp; 1467c478bd9Sstevel@tonic-gate (void) __lwp_sigmask(SIG_SETMASK, &uact.sa_mask, NULL); 1477c478bd9Sstevel@tonic-gate 1487c478bd9Sstevel@tonic-gate /* 1497c478bd9Sstevel@tonic-gate * If this thread has been sent SIGCANCEL from the kernel 1507c478bd9Sstevel@tonic-gate * or from pthread_cancel(), it is being asked to exit. 1517c478bd9Sstevel@tonic-gate * The kernel may send SIGCANCEL without a siginfo struct. 1527c478bd9Sstevel@tonic-gate * If the SIGCANCEL is process-directed (from kill() or 1537c478bd9Sstevel@tonic-gate * sigqueue()), treat it as an ordinary signal. 1547c478bd9Sstevel@tonic-gate */ 1557c478bd9Sstevel@tonic-gate if (sig == SIGCANCEL) { 1567c478bd9Sstevel@tonic-gate if (sip == NULL || SI_FROMKERNEL(sip) || 1577c478bd9Sstevel@tonic-gate sip->si_code == SI_LWP) { 1587c478bd9Sstevel@tonic-gate do_sigcancel(); 1597c478bd9Sstevel@tonic-gate goto out; 1607c478bd9Sstevel@tonic-gate } 161f841f6adSraf /* SIGCANCEL is ignored by default */ 162f841f6adSraf if (uact.sa_sigaction == SIG_DFL || 163f841f6adSraf uact.sa_sigaction == SIG_IGN) 164f841f6adSraf goto out; 165f841f6adSraf } 166f841f6adSraf 167f841f6adSraf /* 168f841f6adSraf * If this thread has been sent SIGAIOCANCEL (SIGLWP) and 169f841f6adSraf * we are an aio worker thread, cancel the aio request. 170f841f6adSraf */ 171f841f6adSraf if (sig == SIGAIOCANCEL) { 172f841f6adSraf aio_worker_t *aiowp = _pthread_getspecific(_aio_key); 173f841f6adSraf 174f841f6adSraf if (sip != NULL && sip->si_code == SI_LWP && aiowp != NULL) 175f841f6adSraf _siglongjmp(aiowp->work_jmp_buf, 1); 176f841f6adSraf /* SIGLWP is ignored by default */ 1777c478bd9Sstevel@tonic-gate if (uact.sa_sigaction == SIG_DFL || 1787c478bd9Sstevel@tonic-gate uact.sa_sigaction == SIG_IGN) 1797c478bd9Sstevel@tonic-gate goto out; 1807c478bd9Sstevel@tonic-gate } 1817c478bd9Sstevel@tonic-gate 1827c478bd9Sstevel@tonic-gate if (!(uact.sa_flags & SA_SIGINFO)) 1837c478bd9Sstevel@tonic-gate sip = NULL; 1847c478bd9Sstevel@tonic-gate __sighndlr(sig, sip, ucp, uact.sa_sigaction); 1857c478bd9Sstevel@tonic-gate 1867c478bd9Sstevel@tonic-gate #if defined(sparc) || defined(__sparc) 1877c478bd9Sstevel@tonic-gate /* 1887c478bd9Sstevel@tonic-gate * If this is a floating point exception and the queue 1897c478bd9Sstevel@tonic-gate * is non-empty, pop the top entry from the queue. This 1907c478bd9Sstevel@tonic-gate * is to maintain expected behavior. 1917c478bd9Sstevel@tonic-gate */ 1927c478bd9Sstevel@tonic-gate if (sig == SIGFPE && ucp->uc_mcontext.fpregs.fpu_qcnt) { 1937c478bd9Sstevel@tonic-gate fpregset_t *fp = &ucp->uc_mcontext.fpregs; 1947c478bd9Sstevel@tonic-gate 1957c478bd9Sstevel@tonic-gate if (--fp->fpu_qcnt > 0) { 1967c478bd9Sstevel@tonic-gate unsigned char i; 1977c478bd9Sstevel@tonic-gate struct fq *fqp; 1987c478bd9Sstevel@tonic-gate 1997c478bd9Sstevel@tonic-gate fqp = fp->fpu_q; 2007c478bd9Sstevel@tonic-gate for (i = 0; i < fp->fpu_qcnt; i++) 2017c478bd9Sstevel@tonic-gate fqp[i] = fqp[i+1]; 2027c478bd9Sstevel@tonic-gate } 2037c478bd9Sstevel@tonic-gate } 2047c478bd9Sstevel@tonic-gate #endif /* sparc */ 2057c478bd9Sstevel@tonic-gate 2067c478bd9Sstevel@tonic-gate out: 2077c478bd9Sstevel@tonic-gate (void) _private_setcontext(ucp); 2087c478bd9Sstevel@tonic-gate thr_panic("call_user_handler(): _setcontext() returned"); 2097c478bd9Sstevel@tonic-gate } 2107c478bd9Sstevel@tonic-gate 2117c478bd9Sstevel@tonic-gate /* 2127c478bd9Sstevel@tonic-gate * take_deferred_signal() is called when ul_critical and ul_sigdefer become 2137c478bd9Sstevel@tonic-gate * zero and a deferred signal has been recorded on the current thread. 2147c478bd9Sstevel@tonic-gate * We are out of the critical region and are ready to take a signal. 2157c478bd9Sstevel@tonic-gate * The kernel has all signals blocked on this lwp, but our value of 2167c478bd9Sstevel@tonic-gate * ul_sigmask is the correct signal mask for the previous context. 2177c478bd9Sstevel@tonic-gate */ 2187c478bd9Sstevel@tonic-gate void 2197c478bd9Sstevel@tonic-gate take_deferred_signal(int sig) 2207c478bd9Sstevel@tonic-gate { 2217c478bd9Sstevel@tonic-gate ulwp_t *self = curthread; 2227c478bd9Sstevel@tonic-gate siginfo_t siginfo; 2237c478bd9Sstevel@tonic-gate siginfo_t *sip; 2247c478bd9Sstevel@tonic-gate ucontext_t uc; 2257c478bd9Sstevel@tonic-gate volatile int returning; 2267c478bd9Sstevel@tonic-gate 2277c478bd9Sstevel@tonic-gate ASSERT(self->ul_critical == 0); 2287c478bd9Sstevel@tonic-gate ASSERT(self->ul_sigdefer == 0); 2297c478bd9Sstevel@tonic-gate ASSERT(self->ul_cursig == 0); 2307c478bd9Sstevel@tonic-gate 2317c478bd9Sstevel@tonic-gate returning = 0; 2327c478bd9Sstevel@tonic-gate uc.uc_flags = UC_ALL; 2337c478bd9Sstevel@tonic-gate /* 2347c478bd9Sstevel@tonic-gate * We call _private_getcontext (a libc-private synonym for 2357c478bd9Sstevel@tonic-gate * _getcontext) rather than _getcontext because we need to 2367c478bd9Sstevel@tonic-gate * avoid the dynamic linker and link auditing problems here. 2377c478bd9Sstevel@tonic-gate */ 2387c478bd9Sstevel@tonic-gate (void) _private_getcontext(&uc); 2397c478bd9Sstevel@tonic-gate /* 2407c478bd9Sstevel@tonic-gate * If the application signal handler calls setcontext() on 2417c478bd9Sstevel@tonic-gate * the ucontext we give it, it returns here, then we return. 2427c478bd9Sstevel@tonic-gate */ 2437c478bd9Sstevel@tonic-gate if (returning) 2447c478bd9Sstevel@tonic-gate return; 2457c478bd9Sstevel@tonic-gate returning = 1; 2467c478bd9Sstevel@tonic-gate ASSERT(sigequalset(&uc.uc_sigmask, &maskset)); 2477c478bd9Sstevel@tonic-gate if (self->ul_siginfo.si_signo == 0) 2487c478bd9Sstevel@tonic-gate sip = NULL; 2497c478bd9Sstevel@tonic-gate else { 2500293487cSraf (void) _private_memcpy(&siginfo, 2510293487cSraf &self->ul_siginfo, sizeof (siginfo)); 2527c478bd9Sstevel@tonic-gate sip = &siginfo; 2537c478bd9Sstevel@tonic-gate } 2547c478bd9Sstevel@tonic-gate uc.uc_sigmask = self->ul_sigmask; 2557c478bd9Sstevel@tonic-gate call_user_handler(sig, sip, &uc); 2567c478bd9Sstevel@tonic-gate } 2577c478bd9Sstevel@tonic-gate 2587c478bd9Sstevel@tonic-gate void 2597c478bd9Sstevel@tonic-gate sigacthandler(int sig, siginfo_t *sip, void *uvp) 2607c478bd9Sstevel@tonic-gate { 2617c478bd9Sstevel@tonic-gate ucontext_t *ucp = uvp; 2627c478bd9Sstevel@tonic-gate ulwp_t *self = curthread; 2637c478bd9Sstevel@tonic-gate 2647c478bd9Sstevel@tonic-gate /* 2657c478bd9Sstevel@tonic-gate * Do this in case we took a signal while in a cancelable system call. 2667c478bd9Sstevel@tonic-gate * It does no harm if we were not in such a system call. 2677c478bd9Sstevel@tonic-gate */ 2687c478bd9Sstevel@tonic-gate self->ul_sp = 0; 2697c478bd9Sstevel@tonic-gate if (sig != SIGCANCEL) 2707c478bd9Sstevel@tonic-gate self->ul_cancel_async = self->ul_save_async; 2717c478bd9Sstevel@tonic-gate 2727c478bd9Sstevel@tonic-gate /* 2737c478bd9Sstevel@tonic-gate * If we are not in a critical region and are 2747c478bd9Sstevel@tonic-gate * not deferring signals, take the signal now. 2757c478bd9Sstevel@tonic-gate */ 2767c478bd9Sstevel@tonic-gate if ((self->ul_critical + self->ul_sigdefer) == 0) { 2777c478bd9Sstevel@tonic-gate call_user_handler(sig, sip, ucp); 2787c478bd9Sstevel@tonic-gate return; /* call_user_handler() cannot return */ 2797c478bd9Sstevel@tonic-gate } 2807c478bd9Sstevel@tonic-gate 2817c478bd9Sstevel@tonic-gate /* 2827c478bd9Sstevel@tonic-gate * We are in a critical region or we are deferring signals. When 2837c478bd9Sstevel@tonic-gate * we emerge from the region we will call take_deferred_signal(). 2847c478bd9Sstevel@tonic-gate */ 2857c478bd9Sstevel@tonic-gate ASSERT(self->ul_cursig == 0); 2867c478bd9Sstevel@tonic-gate self->ul_cursig = (char)sig; 2877c478bd9Sstevel@tonic-gate if (sip != NULL) 2880293487cSraf (void) _private_memcpy(&self->ul_siginfo, 2890293487cSraf sip, sizeof (siginfo_t)); 2907c478bd9Sstevel@tonic-gate else 2917c478bd9Sstevel@tonic-gate self->ul_siginfo.si_signo = 0; 2927c478bd9Sstevel@tonic-gate 2937c478bd9Sstevel@tonic-gate /* 2947c478bd9Sstevel@tonic-gate * Make sure that if we return to a call to __lwp_park() 2957c478bd9Sstevel@tonic-gate * or ___lwp_cond_wait() that it returns right away 2967c478bd9Sstevel@tonic-gate * (giving us a spurious wakeup but not a deadlock). 2977c478bd9Sstevel@tonic-gate */ 2987c478bd9Sstevel@tonic-gate set_parking_flag(self, 0); 2997c478bd9Sstevel@tonic-gate 3007c478bd9Sstevel@tonic-gate /* 3017c478bd9Sstevel@tonic-gate * Return to the previous context with all signals blocked. 3027c478bd9Sstevel@tonic-gate * We will restore the signal mask in take_deferred_signal(). 3037c478bd9Sstevel@tonic-gate * Note that we are calling the system call trap here, not 3047c478bd9Sstevel@tonic-gate * the _setcontext() wrapper. We don't want to change the 3057c478bd9Sstevel@tonic-gate * thread's ul_sigmask by this operation. 3067c478bd9Sstevel@tonic-gate */ 3077c478bd9Sstevel@tonic-gate ucp->uc_sigmask = maskset; 3087c478bd9Sstevel@tonic-gate (void) __setcontext_syscall(ucp); 3097c478bd9Sstevel@tonic-gate thr_panic("sigacthandler(): __setcontext() returned"); 3107c478bd9Sstevel@tonic-gate } 3117c478bd9Sstevel@tonic-gate 3129acbbeafSnn #pragma weak sigaction = _libc_sigaction 3139acbbeafSnn #pragma weak _sigaction = _libc_sigaction 3147c478bd9Sstevel@tonic-gate int 3159acbbeafSnn _libc_sigaction(int sig, const struct sigaction *nact, struct sigaction *oact) 3167c478bd9Sstevel@tonic-gate { 3177c478bd9Sstevel@tonic-gate ulwp_t *self = curthread; 3187c478bd9Sstevel@tonic-gate uberdata_t *udp = self->ul_uberdata; 3197c478bd9Sstevel@tonic-gate struct sigaction oaction; 3207c478bd9Sstevel@tonic-gate struct sigaction tact; 3217c478bd9Sstevel@tonic-gate struct sigaction *tactp = NULL; 3227c478bd9Sstevel@tonic-gate int rv; 3237c478bd9Sstevel@tonic-gate 3247c478bd9Sstevel@tonic-gate if (sig <= 0 || sig >= NSIG) { 3257c478bd9Sstevel@tonic-gate errno = EINVAL; 3267c478bd9Sstevel@tonic-gate return (-1); 3277c478bd9Sstevel@tonic-gate } 3287c478bd9Sstevel@tonic-gate 3297c478bd9Sstevel@tonic-gate if (!self->ul_vfork) 330*41efec22Sraf lrw_wrlock(&udp->siguaction[sig].sig_lock); 3317c478bd9Sstevel@tonic-gate 3327c478bd9Sstevel@tonic-gate oaction = udp->siguaction[sig].sig_uaction; 3337c478bd9Sstevel@tonic-gate 3347c478bd9Sstevel@tonic-gate if (nact != NULL) { 3357c478bd9Sstevel@tonic-gate tact = *nact; /* make a copy so we can modify it */ 3367c478bd9Sstevel@tonic-gate tactp = &tact; 3377c478bd9Sstevel@tonic-gate delete_reserved_signals(&tact.sa_mask); 3387c478bd9Sstevel@tonic-gate 3397c478bd9Sstevel@tonic-gate #if !defined(_LP64) 3407c478bd9Sstevel@tonic-gate tact.sa_resv[0] = tact.sa_resv[1] = 0; /* cleanliness */ 3417c478bd9Sstevel@tonic-gate #endif 3427c478bd9Sstevel@tonic-gate /* 3437c478bd9Sstevel@tonic-gate * To be compatible with the behavior of SunOS 4.x: 3447c478bd9Sstevel@tonic-gate * If the new signal handler is SIG_IGN or SIG_DFL, do 3457c478bd9Sstevel@tonic-gate * not change the signal's entry in the siguaction array. 3467c478bd9Sstevel@tonic-gate * This allows a child of vfork(2) to set signal handlers 3477c478bd9Sstevel@tonic-gate * to SIG_IGN or SIG_DFL without affecting the parent. 3487c478bd9Sstevel@tonic-gate * 3497c478bd9Sstevel@tonic-gate * This also covers a race condition with some thread 3507c478bd9Sstevel@tonic-gate * setting the signal action to SIG_DFL or SIG_IGN 3517c478bd9Sstevel@tonic-gate * when the thread has also received and deferred 3527c478bd9Sstevel@tonic-gate * that signal. When the thread takes the deferred 3537c478bd9Sstevel@tonic-gate * signal, even though it has set the action to SIG_DFL 3547c478bd9Sstevel@tonic-gate * or SIG_IGN, it will execute the old signal handler 3557c478bd9Sstevel@tonic-gate * anyway. This is an inherent signaling race condition 3567c478bd9Sstevel@tonic-gate * and is not a bug. 3577c478bd9Sstevel@tonic-gate * 3587c478bd9Sstevel@tonic-gate * A child of vfork() is not allowed to change signal 3597c478bd9Sstevel@tonic-gate * handlers to anything other than SIG_DFL or SIG_IGN. 3607c478bd9Sstevel@tonic-gate */ 3617c478bd9Sstevel@tonic-gate if (self->ul_vfork) { 3627c478bd9Sstevel@tonic-gate if (tact.sa_sigaction != SIG_IGN) 3637c478bd9Sstevel@tonic-gate tact.sa_sigaction = SIG_DFL; 364f841f6adSraf } else if (sig == SIGCANCEL || sig == SIGAIOCANCEL) { 3657c478bd9Sstevel@tonic-gate /* 366f841f6adSraf * Always catch these signals. 367f841f6adSraf * We need SIGCANCEL for pthread_cancel() to work. 368f841f6adSraf * We need SIGAIOCANCEL for aio_cancel() to work. 3697c478bd9Sstevel@tonic-gate */ 3707c478bd9Sstevel@tonic-gate udp->siguaction[sig].sig_uaction = tact; 3717c478bd9Sstevel@tonic-gate if (tact.sa_sigaction == SIG_DFL || 3727c478bd9Sstevel@tonic-gate tact.sa_sigaction == SIG_IGN) 3737c478bd9Sstevel@tonic-gate tact.sa_flags = SA_SIGINFO; 3747c478bd9Sstevel@tonic-gate else { 3757c478bd9Sstevel@tonic-gate tact.sa_flags |= SA_SIGINFO; 3767c478bd9Sstevel@tonic-gate tact.sa_flags &= ~(SA_NODEFER | SA_RESETHAND); 3777c478bd9Sstevel@tonic-gate } 3787c478bd9Sstevel@tonic-gate tact.sa_sigaction = udp->sigacthandler; 3797c478bd9Sstevel@tonic-gate tact.sa_mask = maskset; 3807c478bd9Sstevel@tonic-gate } else if (tact.sa_sigaction != SIG_DFL && 3817c478bd9Sstevel@tonic-gate tact.sa_sigaction != SIG_IGN) { 3827c478bd9Sstevel@tonic-gate udp->siguaction[sig].sig_uaction = tact; 3837c478bd9Sstevel@tonic-gate tact.sa_flags &= ~SA_NODEFER; 3847c478bd9Sstevel@tonic-gate tact.sa_sigaction = udp->sigacthandler; 3857c478bd9Sstevel@tonic-gate tact.sa_mask = maskset; 3867c478bd9Sstevel@tonic-gate } 3877c478bd9Sstevel@tonic-gate } 3887c478bd9Sstevel@tonic-gate 3897c478bd9Sstevel@tonic-gate if ((rv = __sigaction(sig, tactp, oact)) != 0) 3907c478bd9Sstevel@tonic-gate udp->siguaction[sig].sig_uaction = oaction; 3917c478bd9Sstevel@tonic-gate else if (oact != NULL && 3927c478bd9Sstevel@tonic-gate oact->sa_sigaction != SIG_DFL && 3937c478bd9Sstevel@tonic-gate oact->sa_sigaction != SIG_IGN) 3947c478bd9Sstevel@tonic-gate *oact = oaction; 3957c478bd9Sstevel@tonic-gate 396f841f6adSraf /* 397f841f6adSraf * We detect setting the disposition of SIGIO just to set the 398f841f6adSraf * _sigio_enabled flag for the asynchronous i/o (aio) code. 399f841f6adSraf */ 400f841f6adSraf if (sig == SIGIO && rv == 0 && tactp != NULL) { 401f841f6adSraf _sigio_enabled = 402f841f6adSraf (tactp->sa_handler != SIG_DFL && 403f841f6adSraf tactp->sa_handler != SIG_IGN); 404f841f6adSraf } 405f841f6adSraf 4067c478bd9Sstevel@tonic-gate if (!self->ul_vfork) 407*41efec22Sraf lrw_unlock(&udp->siguaction[sig].sig_lock); 4087c478bd9Sstevel@tonic-gate return (rv); 4097c478bd9Sstevel@tonic-gate } 4107c478bd9Sstevel@tonic-gate 4119acbbeafSnn void 4129acbbeafSnn setsigacthandler(void (*nsigacthandler)(int, siginfo_t *, void *), 4139acbbeafSnn void (**osigacthandler)(int, siginfo_t *, void *)) 4149acbbeafSnn { 4159acbbeafSnn ulwp_t *self = curthread; 4169acbbeafSnn uberdata_t *udp = self->ul_uberdata; 4179acbbeafSnn 4189acbbeafSnn if (osigacthandler != NULL) 4199acbbeafSnn *osigacthandler = udp->sigacthandler; 4209acbbeafSnn 4219acbbeafSnn udp->sigacthandler = nsigacthandler; 4229acbbeafSnn } 4239acbbeafSnn 4247c478bd9Sstevel@tonic-gate /* 4257c478bd9Sstevel@tonic-gate * Calling set_parking_flag(curthread, 1) informs the kernel that we are 4267c478bd9Sstevel@tonic-gate * calling __lwp_park or ___lwp_cond_wait(). If we take a signal in 4277c478bd9Sstevel@tonic-gate * the unprotected (from signals) interval before reaching the kernel, 4287c478bd9Sstevel@tonic-gate * sigacthandler() will call set_parking_flag(curthread, 0) to inform 4297c478bd9Sstevel@tonic-gate * the kernel to return immediately from these system calls, giving us 4307c478bd9Sstevel@tonic-gate * a spurious wakeup but not a deadlock. 4317c478bd9Sstevel@tonic-gate */ 4327c478bd9Sstevel@tonic-gate void 4337c478bd9Sstevel@tonic-gate set_parking_flag(ulwp_t *self, int park) 4347c478bd9Sstevel@tonic-gate { 4357c478bd9Sstevel@tonic-gate volatile sc_shared_t *scp; 4367c478bd9Sstevel@tonic-gate 4377c478bd9Sstevel@tonic-gate enter_critical(self); 4387c478bd9Sstevel@tonic-gate if ((scp = self->ul_schedctl) != NULL || 4397c478bd9Sstevel@tonic-gate (scp = setup_schedctl()) != NULL) 4407c478bd9Sstevel@tonic-gate scp->sc_park = park; 4417c478bd9Sstevel@tonic-gate else if (park == 0) /* schedctl failed, do it the long way */ 4427c478bd9Sstevel@tonic-gate __lwp_unpark(self->ul_lwpid); 4437c478bd9Sstevel@tonic-gate exit_critical(self); 4447c478bd9Sstevel@tonic-gate } 4457c478bd9Sstevel@tonic-gate 4467c478bd9Sstevel@tonic-gate /* 4477c478bd9Sstevel@tonic-gate * Tell the kernel to block all signals. 4487c478bd9Sstevel@tonic-gate * Use the schedctl interface, or failing that, use __lwp_sigmask(). 4497c478bd9Sstevel@tonic-gate * This action can be rescinded only by making a system call that 4507c478bd9Sstevel@tonic-gate * sets the signal mask: 4517c478bd9Sstevel@tonic-gate * __lwp_sigmask(), __sigprocmask(), __setcontext(), 4527c478bd9Sstevel@tonic-gate * __sigsuspend() or __pollsys(). 4537c478bd9Sstevel@tonic-gate * In particular, this action cannot be reversed by assigning 4547c478bd9Sstevel@tonic-gate * scp->sc_sigblock = 0. That would be a way to lose signals. 4557c478bd9Sstevel@tonic-gate * See the definition of restore_signals(self). 4567c478bd9Sstevel@tonic-gate */ 4577c478bd9Sstevel@tonic-gate void 4587c478bd9Sstevel@tonic-gate block_all_signals(ulwp_t *self) 4597c478bd9Sstevel@tonic-gate { 4607c478bd9Sstevel@tonic-gate volatile sc_shared_t *scp; 4617c478bd9Sstevel@tonic-gate 4627c478bd9Sstevel@tonic-gate enter_critical(self); 4637c478bd9Sstevel@tonic-gate if ((scp = self->ul_schedctl) != NULL || 4647c478bd9Sstevel@tonic-gate (scp = setup_schedctl()) != NULL) 4657c478bd9Sstevel@tonic-gate scp->sc_sigblock = 1; 4667c478bd9Sstevel@tonic-gate else 4677c478bd9Sstevel@tonic-gate (void) __lwp_sigmask(SIG_SETMASK, &maskset, NULL); 4687c478bd9Sstevel@tonic-gate exit_critical(self); 4697c478bd9Sstevel@tonic-gate } 4707c478bd9Sstevel@tonic-gate 4719acbbeafSnn /* 4729acbbeafSnn * _private_setcontext has code that forcibly restores the curthread 4739acbbeafSnn * pointer in a context passed to the setcontext(2) syscall. 4749acbbeafSnn * 4759acbbeafSnn * Certain processes may need to disable this feature, so these routines 4769acbbeafSnn * provide the mechanism to do so. 4779acbbeafSnn * 4789acbbeafSnn * (As an example, branded 32-bit x86 processes may use %gs for their own 4799acbbeafSnn * purposes, so they need to be able to specify a %gs value to be restored 4809acbbeafSnn * on return from a signal handler via the passed ucontext_t.) 4819acbbeafSnn */ 4829acbbeafSnn static int setcontext_enforcement = 1; 4839acbbeafSnn 4849acbbeafSnn void 4859acbbeafSnn set_setcontext_enforcement(int on) 4869acbbeafSnn { 4879acbbeafSnn setcontext_enforcement = on; 4889acbbeafSnn } 4899acbbeafSnn 4907c478bd9Sstevel@tonic-gate #pragma weak setcontext = _private_setcontext 4917c478bd9Sstevel@tonic-gate #pragma weak _setcontext = _private_setcontext 4927c478bd9Sstevel@tonic-gate int 4937c478bd9Sstevel@tonic-gate _private_setcontext(const ucontext_t *ucp) 4947c478bd9Sstevel@tonic-gate { 4957c478bd9Sstevel@tonic-gate ulwp_t *self = curthread; 4967c478bd9Sstevel@tonic-gate int ret; 4977c478bd9Sstevel@tonic-gate ucontext_t uc; 4987c478bd9Sstevel@tonic-gate 4997c478bd9Sstevel@tonic-gate /* 5007c478bd9Sstevel@tonic-gate * Returning from the main context (uc_link == NULL) causes 5017c478bd9Sstevel@tonic-gate * the thread to exit. See setcontext(2) and makecontext(3C). 5027c478bd9Sstevel@tonic-gate */ 5037c478bd9Sstevel@tonic-gate if (ucp == NULL) 5047c478bd9Sstevel@tonic-gate _thr_exit(NULL); 5050293487cSraf (void) _private_memcpy(&uc, ucp, sizeof (uc)); 5067c478bd9Sstevel@tonic-gate 5077c478bd9Sstevel@tonic-gate /* 5087c478bd9Sstevel@tonic-gate * Restore previous signal mask and context link. 5097c478bd9Sstevel@tonic-gate */ 5107c478bd9Sstevel@tonic-gate if (uc.uc_flags & UC_SIGMASK) { 5117c478bd9Sstevel@tonic-gate block_all_signals(self); 5127c478bd9Sstevel@tonic-gate delete_reserved_signals(&uc.uc_sigmask); 5137c478bd9Sstevel@tonic-gate self->ul_sigmask = uc.uc_sigmask; 5147c478bd9Sstevel@tonic-gate if (self->ul_cursig) { 5157c478bd9Sstevel@tonic-gate /* 5167c478bd9Sstevel@tonic-gate * We have a deferred signal present. 5177c478bd9Sstevel@tonic-gate * The signal mask will be set when the 5187c478bd9Sstevel@tonic-gate * signal is taken in take_deferred_signal(). 5197c478bd9Sstevel@tonic-gate */ 5207c478bd9Sstevel@tonic-gate ASSERT(self->ul_critical + self->ul_sigdefer != 0); 5217c478bd9Sstevel@tonic-gate uc.uc_flags &= ~UC_SIGMASK; 5227c478bd9Sstevel@tonic-gate } 5237c478bd9Sstevel@tonic-gate } 5247c478bd9Sstevel@tonic-gate self->ul_siglink = uc.uc_link; 5257c478bd9Sstevel@tonic-gate 5267c478bd9Sstevel@tonic-gate /* 5277c478bd9Sstevel@tonic-gate * We don't know where this context structure has been. 5287c478bd9Sstevel@tonic-gate * Preserve the curthread pointer, at least. 5299acbbeafSnn * 5309acbbeafSnn * Allow this feature to be disabled if a particular process 5319acbbeafSnn * requests it. 5327c478bd9Sstevel@tonic-gate */ 5339acbbeafSnn if (setcontext_enforcement) { 5347c478bd9Sstevel@tonic-gate #if defined(__sparc) 5359acbbeafSnn uc.uc_mcontext.gregs[REG_G7] = (greg_t)self; 5367c478bd9Sstevel@tonic-gate #elif defined(__amd64) 537ae115bc7Smrj uc.uc_mcontext.gregs[REG_FS] = (greg_t)0; /* null for fsbase */ 5387c478bd9Sstevel@tonic-gate #elif defined(__i386) 539ae115bc7Smrj uc.uc_mcontext.gregs[GS] = (greg_t)LWPGS_SEL; 5407c478bd9Sstevel@tonic-gate #else 5417c478bd9Sstevel@tonic-gate #error "none of __sparc, __amd64, __i386 defined" 5427c478bd9Sstevel@tonic-gate #endif 5439acbbeafSnn } 5449acbbeafSnn 5457c478bd9Sstevel@tonic-gate /* 5467c478bd9Sstevel@tonic-gate * Make sure that if we return to a call to __lwp_park() 5477c478bd9Sstevel@tonic-gate * or ___lwp_cond_wait() that it returns right away 5487c478bd9Sstevel@tonic-gate * (giving us a spurious wakeup but not a deadlock). 5497c478bd9Sstevel@tonic-gate */ 5507c478bd9Sstevel@tonic-gate set_parking_flag(self, 0); 5517c478bd9Sstevel@tonic-gate self->ul_sp = 0; 5527c478bd9Sstevel@tonic-gate ret = __setcontext_syscall(&uc); 5537c478bd9Sstevel@tonic-gate 5547c478bd9Sstevel@tonic-gate /* 5557c478bd9Sstevel@tonic-gate * It is OK for setcontext() to return if the user has not specified 5567c478bd9Sstevel@tonic-gate * UC_CPU. 5577c478bd9Sstevel@tonic-gate */ 5587c478bd9Sstevel@tonic-gate if (uc.uc_flags & UC_CPU) 5597c478bd9Sstevel@tonic-gate thr_panic("setcontext(): __setcontext() returned"); 5607c478bd9Sstevel@tonic-gate return (ret); 5617c478bd9Sstevel@tonic-gate } 5627c478bd9Sstevel@tonic-gate 5637c478bd9Sstevel@tonic-gate #pragma weak thr_sigsetmask = _thr_sigsetmask 5647c478bd9Sstevel@tonic-gate #pragma weak pthread_sigmask = _thr_sigsetmask 5657c478bd9Sstevel@tonic-gate #pragma weak _pthread_sigmask = _thr_sigsetmask 5667c478bd9Sstevel@tonic-gate int 5677c478bd9Sstevel@tonic-gate _thr_sigsetmask(int how, const sigset_t *set, sigset_t *oset) 5687c478bd9Sstevel@tonic-gate { 5697c478bd9Sstevel@tonic-gate ulwp_t *self = curthread; 5707c478bd9Sstevel@tonic-gate sigset_t saveset; 5717c478bd9Sstevel@tonic-gate 5727c478bd9Sstevel@tonic-gate if (set == NULL) { 5737c478bd9Sstevel@tonic-gate enter_critical(self); 5747c478bd9Sstevel@tonic-gate if (oset != NULL) 5757c478bd9Sstevel@tonic-gate *oset = self->ul_sigmask; 5767c478bd9Sstevel@tonic-gate exit_critical(self); 5777c478bd9Sstevel@tonic-gate } else { 5787c478bd9Sstevel@tonic-gate switch (how) { 5797c478bd9Sstevel@tonic-gate case SIG_BLOCK: 5807c478bd9Sstevel@tonic-gate case SIG_UNBLOCK: 5817c478bd9Sstevel@tonic-gate case SIG_SETMASK: 5827c478bd9Sstevel@tonic-gate break; 5837c478bd9Sstevel@tonic-gate default: 5847c478bd9Sstevel@tonic-gate return (EINVAL); 5857c478bd9Sstevel@tonic-gate } 5867c478bd9Sstevel@tonic-gate 5877c478bd9Sstevel@tonic-gate /* 5887c478bd9Sstevel@tonic-gate * The assignments to self->ul_sigmask must be protected from 5897c478bd9Sstevel@tonic-gate * signals. The nuances of this code are subtle. Be careful. 5907c478bd9Sstevel@tonic-gate */ 5917c478bd9Sstevel@tonic-gate block_all_signals(self); 5927c478bd9Sstevel@tonic-gate if (oset != NULL) 5937c478bd9Sstevel@tonic-gate saveset = self->ul_sigmask; 5947c478bd9Sstevel@tonic-gate switch (how) { 5957c478bd9Sstevel@tonic-gate case SIG_BLOCK: 5967c478bd9Sstevel@tonic-gate self->ul_sigmask.__sigbits[0] |= set->__sigbits[0]; 5977c478bd9Sstevel@tonic-gate self->ul_sigmask.__sigbits[1] |= set->__sigbits[1]; 5987c478bd9Sstevel@tonic-gate break; 5997c478bd9Sstevel@tonic-gate case SIG_UNBLOCK: 6007c478bd9Sstevel@tonic-gate self->ul_sigmask.__sigbits[0] &= ~set->__sigbits[0]; 6017c478bd9Sstevel@tonic-gate self->ul_sigmask.__sigbits[1] &= ~set->__sigbits[1]; 6027c478bd9Sstevel@tonic-gate break; 6037c478bd9Sstevel@tonic-gate case SIG_SETMASK: 6047c478bd9Sstevel@tonic-gate self->ul_sigmask.__sigbits[0] = set->__sigbits[0]; 6057c478bd9Sstevel@tonic-gate self->ul_sigmask.__sigbits[1] = set->__sigbits[1]; 6067c478bd9Sstevel@tonic-gate break; 6077c478bd9Sstevel@tonic-gate } 6087c478bd9Sstevel@tonic-gate delete_reserved_signals(&self->ul_sigmask); 6097c478bd9Sstevel@tonic-gate if (oset != NULL) 6107c478bd9Sstevel@tonic-gate *oset = saveset; 6117c478bd9Sstevel@tonic-gate restore_signals(self); 6127c478bd9Sstevel@tonic-gate } 6137c478bd9Sstevel@tonic-gate 6147c478bd9Sstevel@tonic-gate return (0); 6157c478bd9Sstevel@tonic-gate } 6167c478bd9Sstevel@tonic-gate 6177c478bd9Sstevel@tonic-gate #pragma weak sigprocmask = _sigprocmask 6187c478bd9Sstevel@tonic-gate int 6197c478bd9Sstevel@tonic-gate _sigprocmask(int how, const sigset_t *set, sigset_t *oset) 6207c478bd9Sstevel@tonic-gate { 6217c478bd9Sstevel@tonic-gate int error; 6227c478bd9Sstevel@tonic-gate 6237c478bd9Sstevel@tonic-gate /* 6247c478bd9Sstevel@tonic-gate * Guard against children of vfork(). 6257c478bd9Sstevel@tonic-gate */ 6267c478bd9Sstevel@tonic-gate if (curthread->ul_vfork) 6277c478bd9Sstevel@tonic-gate return (__lwp_sigmask(how, set, oset)); 6287c478bd9Sstevel@tonic-gate 6297c478bd9Sstevel@tonic-gate if ((error = _thr_sigsetmask(how, set, oset)) != 0) { 6307c478bd9Sstevel@tonic-gate errno = error; 6317c478bd9Sstevel@tonic-gate return (-1); 6327c478bd9Sstevel@tonic-gate } 6337c478bd9Sstevel@tonic-gate 6347c478bd9Sstevel@tonic-gate return (0); 6357c478bd9Sstevel@tonic-gate } 6367c478bd9Sstevel@tonic-gate 6377c478bd9Sstevel@tonic-gate /* 6387c478bd9Sstevel@tonic-gate * Called at library initialization to set up signal handling. 639*41efec22Sraf * All we really do is initialize the sig_lock rwlocks. 6407c478bd9Sstevel@tonic-gate * All signal handlers are either SIG_DFL or SIG_IGN on exec(). 6417c478bd9Sstevel@tonic-gate * However, if any signal handlers were established on alternate 6427c478bd9Sstevel@tonic-gate * link maps before the primary link map has been initialized, 6437c478bd9Sstevel@tonic-gate * then inform the kernel of the new sigacthandler. 6447c478bd9Sstevel@tonic-gate */ 6457c478bd9Sstevel@tonic-gate void 6467c478bd9Sstevel@tonic-gate signal_init() 6477c478bd9Sstevel@tonic-gate { 6487c478bd9Sstevel@tonic-gate uberdata_t *udp = curthread->ul_uberdata; 6497c478bd9Sstevel@tonic-gate struct sigaction *sap; 6507c478bd9Sstevel@tonic-gate struct sigaction act; 651*41efec22Sraf rwlock_t *rwlp; 6527c478bd9Sstevel@tonic-gate int sig; 6537c478bd9Sstevel@tonic-gate 6547c478bd9Sstevel@tonic-gate for (sig = 0; sig < NSIG; sig++) { 655*41efec22Sraf rwlp = &udp->siguaction[sig].sig_lock; 656*41efec22Sraf rwlp->rwlock_magic = RWL_MAGIC; 657*41efec22Sraf rwlp->mutex.mutex_flag = LOCK_INITED; 658*41efec22Sraf rwlp->mutex.mutex_magic = MUTEX_MAGIC; 6597c478bd9Sstevel@tonic-gate sap = &udp->siguaction[sig].sig_uaction; 6607c478bd9Sstevel@tonic-gate if (sap->sa_sigaction != SIG_DFL && 6617c478bd9Sstevel@tonic-gate sap->sa_sigaction != SIG_IGN && 6627c478bd9Sstevel@tonic-gate __sigaction(sig, NULL, &act) == 0 && 6637c478bd9Sstevel@tonic-gate act.sa_sigaction != SIG_DFL && 6647c478bd9Sstevel@tonic-gate act.sa_sigaction != SIG_IGN) { 6657c478bd9Sstevel@tonic-gate act = *sap; 6667c478bd9Sstevel@tonic-gate act.sa_flags &= ~SA_NODEFER; 6677c478bd9Sstevel@tonic-gate act.sa_sigaction = udp->sigacthandler; 6687c478bd9Sstevel@tonic-gate act.sa_mask = maskset; 6697c478bd9Sstevel@tonic-gate (void) __sigaction(sig, &act, NULL); 6707c478bd9Sstevel@tonic-gate } 6717c478bd9Sstevel@tonic-gate } 6727c478bd9Sstevel@tonic-gate } 6737c478bd9Sstevel@tonic-gate 6747c478bd9Sstevel@tonic-gate /* 6757c478bd9Sstevel@tonic-gate * Common code for cancelling self in _sigcancel() and pthread_cancel(). 6767c478bd9Sstevel@tonic-gate * If the thread is at a cancellation point (ul_cancelable) then just 6777c478bd9Sstevel@tonic-gate * return and let _canceloff() do the exit, else exit immediately if 6787c478bd9Sstevel@tonic-gate * async mode is in effect. 6797c478bd9Sstevel@tonic-gate */ 6807c478bd9Sstevel@tonic-gate void 6817c478bd9Sstevel@tonic-gate do_sigcancel() 6827c478bd9Sstevel@tonic-gate { 6837c478bd9Sstevel@tonic-gate ulwp_t *self = curthread; 6847c478bd9Sstevel@tonic-gate 6857c478bd9Sstevel@tonic-gate ASSERT(self->ul_critical == 0); 6867c478bd9Sstevel@tonic-gate ASSERT(self->ul_sigdefer == 0); 6877c478bd9Sstevel@tonic-gate self->ul_cancel_pending = 1; 6887c478bd9Sstevel@tonic-gate if (self->ul_cancel_async && 6897c478bd9Sstevel@tonic-gate !self->ul_cancel_disabled && 6907c478bd9Sstevel@tonic-gate !self->ul_cancelable) 6917c478bd9Sstevel@tonic-gate _pthread_exit(PTHREAD_CANCELED); 6927c478bd9Sstevel@tonic-gate } 6937c478bd9Sstevel@tonic-gate 6947c478bd9Sstevel@tonic-gate /* 695f841f6adSraf * Set up the SIGCANCEL handler for threads cancellation, 696f841f6adSraf * needed only when we have more than one thread, 697f841f6adSraf * or the SIGAIOCANCEL handler for aio cancellation, 698f841f6adSraf * called when aio is initialized, in __uaio_init(). 6997c478bd9Sstevel@tonic-gate */ 7007c478bd9Sstevel@tonic-gate void 701f841f6adSraf setup_cancelsig(int sig) 7027c478bd9Sstevel@tonic-gate { 7037c478bd9Sstevel@tonic-gate uberdata_t *udp = curthread->ul_uberdata; 704*41efec22Sraf rwlock_t *rwlp = &udp->siguaction[sig].sig_lock; 7057c478bd9Sstevel@tonic-gate struct sigaction act; 7067c478bd9Sstevel@tonic-gate 707f841f6adSraf ASSERT(sig == SIGCANCEL || sig == SIGAIOCANCEL); 708*41efec22Sraf lrw_rdlock(rwlp); 709f841f6adSraf act = udp->siguaction[sig].sig_uaction; 710*41efec22Sraf lrw_unlock(rwlp); 7117c478bd9Sstevel@tonic-gate if (act.sa_sigaction == SIG_DFL || 7127c478bd9Sstevel@tonic-gate act.sa_sigaction == SIG_IGN) 7137c478bd9Sstevel@tonic-gate act.sa_flags = SA_SIGINFO; 7147c478bd9Sstevel@tonic-gate else { 7157c478bd9Sstevel@tonic-gate act.sa_flags |= SA_SIGINFO; 7167c478bd9Sstevel@tonic-gate act.sa_flags &= ~(SA_NODEFER | SA_RESETHAND); 7177c478bd9Sstevel@tonic-gate } 7187c478bd9Sstevel@tonic-gate act.sa_sigaction = udp->sigacthandler; 7197c478bd9Sstevel@tonic-gate act.sa_mask = maskset; 720f841f6adSraf (void) __sigaction(sig, &act, NULL); 7217c478bd9Sstevel@tonic-gate } 722