1*0Sstevel@tonic-gate /* 2*0Sstevel@tonic-gate * CDDL HEADER START 3*0Sstevel@tonic-gate * 4*0Sstevel@tonic-gate * The contents of this file are subject to the terms of the 5*0Sstevel@tonic-gate * Common Development and Distribution License, Version 1.0 only 6*0Sstevel@tonic-gate * (the "License"). You may not use this file except in compliance 7*0Sstevel@tonic-gate * with the License. 8*0Sstevel@tonic-gate * 9*0Sstevel@tonic-gate * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10*0Sstevel@tonic-gate * or http://www.opensolaris.org/os/licensing. 11*0Sstevel@tonic-gate * See the License for the specific language governing permissions 12*0Sstevel@tonic-gate * and limitations under the License. 13*0Sstevel@tonic-gate * 14*0Sstevel@tonic-gate * When distributing Covered Code, include this CDDL HEADER in each 15*0Sstevel@tonic-gate * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16*0Sstevel@tonic-gate * If applicable, add the following below this CDDL HEADER, with the 17*0Sstevel@tonic-gate * fields enclosed by brackets "[]" replaced with your own identifying 18*0Sstevel@tonic-gate * information: Portions Copyright [yyyy] [name of copyright owner] 19*0Sstevel@tonic-gate * 20*0Sstevel@tonic-gate * CDDL HEADER END 21*0Sstevel@tonic-gate */ 22*0Sstevel@tonic-gate /* 23*0Sstevel@tonic-gate * Copyright 2005 Sun Microsystems, Inc. All rights reserved. 24*0Sstevel@tonic-gate * Use is subject to license terms. 25*0Sstevel@tonic-gate */ 26*0Sstevel@tonic-gate 27*0Sstevel@tonic-gate #pragma ident "%Z%%M% %I% %E% SMI" 28*0Sstevel@tonic-gate 29*0Sstevel@tonic-gate #include "lint.h" 30*0Sstevel@tonic-gate #include "thr_uberdata.h" 31*0Sstevel@tonic-gate 32*0Sstevel@tonic-gate /* 33*0Sstevel@tonic-gate * pthread_cancel: tries to cancel the targeted thread. 34*0Sstevel@tonic-gate * If the target thread has already exited no action is taken. 35*0Sstevel@tonic-gate * Else send SIGCANCEL to request the other thread to cancel itself. 36*0Sstevel@tonic-gate */ 37*0Sstevel@tonic-gate #pragma weak pthread_cancel = _pthread_cancel 38*0Sstevel@tonic-gate int 39*0Sstevel@tonic-gate _pthread_cancel(thread_t tid) 40*0Sstevel@tonic-gate { 41*0Sstevel@tonic-gate ulwp_t *self = curthread; 42*0Sstevel@tonic-gate uberdata_t *udp = self->ul_uberdata; 43*0Sstevel@tonic-gate ulwp_t *ulwp; 44*0Sstevel@tonic-gate int error = 0; 45*0Sstevel@tonic-gate 46*0Sstevel@tonic-gate if ((ulwp = find_lwp(tid)) == NULL) 47*0Sstevel@tonic-gate return (ESRCH); 48*0Sstevel@tonic-gate 49*0Sstevel@tonic-gate if (ulwp->ul_cancel_pending) { 50*0Sstevel@tonic-gate /* 51*0Sstevel@tonic-gate * Don't send SIGCANCEL more than once. 52*0Sstevel@tonic-gate */ 53*0Sstevel@tonic-gate ulwp_unlock(ulwp, udp); 54*0Sstevel@tonic-gate } else if (ulwp == self) { 55*0Sstevel@tonic-gate /* 56*0Sstevel@tonic-gate * Unlock self before cancelling. 57*0Sstevel@tonic-gate */ 58*0Sstevel@tonic-gate ulwp_unlock(ulwp, udp); 59*0Sstevel@tonic-gate ulwp->ul_nocancel = 0; /* cancellation is now possible */ 60*0Sstevel@tonic-gate if (ulwp->ul_sigdefer) 61*0Sstevel@tonic-gate ulwp->ul_cancel_pending = 1; 62*0Sstevel@tonic-gate else 63*0Sstevel@tonic-gate do_sigcancel(); 64*0Sstevel@tonic-gate } else if (ulwp->ul_cancel_disabled) { 65*0Sstevel@tonic-gate /* 66*0Sstevel@tonic-gate * Don't send SIGCANCEL if cancellation is disabled; 67*0Sstevel@tonic-gate * just set the thread's ulwp->ul_cancel_pending flag. 68*0Sstevel@tonic-gate * This avoids a potential EINTR for the target thread. 69*0Sstevel@tonic-gate */ 70*0Sstevel@tonic-gate ulwp->ul_cancel_pending = 1; 71*0Sstevel@tonic-gate ulwp_unlock(ulwp, udp); 72*0Sstevel@tonic-gate } else { 73*0Sstevel@tonic-gate /* 74*0Sstevel@tonic-gate * Request the other thread to cancel itself. 75*0Sstevel@tonic-gate */ 76*0Sstevel@tonic-gate error = __lwp_kill(tid, SIGCANCEL); 77*0Sstevel@tonic-gate ulwp_unlock(ulwp, udp); 78*0Sstevel@tonic-gate } 79*0Sstevel@tonic-gate 80*0Sstevel@tonic-gate return (error); 81*0Sstevel@tonic-gate } 82*0Sstevel@tonic-gate 83*0Sstevel@tonic-gate /* 84*0Sstevel@tonic-gate * pthread_setcancelstate: sets the state ENABLED or DISABLED 85*0Sstevel@tonic-gate * If the state is being set as ENABLED, then it becomes 86*0Sstevel@tonic-gate * a cancellation point only if the type of cancellation is 87*0Sstevel@tonic-gate * ASYNCHRONOUS and a cancel request is pending. 88*0Sstevel@tonic-gate * Disabling cancellation is not a cancellation point. 89*0Sstevel@tonic-gate */ 90*0Sstevel@tonic-gate #pragma weak pthread_setcancelstate = _pthread_setcancelstate 91*0Sstevel@tonic-gate int 92*0Sstevel@tonic-gate _pthread_setcancelstate(int state, int *oldstate) 93*0Sstevel@tonic-gate { 94*0Sstevel@tonic-gate ulwp_t *self = curthread; 95*0Sstevel@tonic-gate uberdata_t *udp = self->ul_uberdata; 96*0Sstevel@tonic-gate int was_disabled; 97*0Sstevel@tonic-gate 98*0Sstevel@tonic-gate /* 99*0Sstevel@tonic-gate * Grab ulwp_lock(self) to protect the setting of ul_cancel_disabled 100*0Sstevel@tonic-gate * since it is tested under this lock by pthread_cancel(), above. 101*0Sstevel@tonic-gate * This has the side-effect of calling enter_critical() and this 102*0Sstevel@tonic-gate * defers SIGCANCEL until ulwp_unlock(self) when exit_critical() 103*0Sstevel@tonic-gate * is called. (self->ul_cancel_pending is set in the SIGCANCEL 104*0Sstevel@tonic-gate * handler and we must be async-signal safe here.) 105*0Sstevel@tonic-gate */ 106*0Sstevel@tonic-gate ulwp_lock(self, udp); 107*0Sstevel@tonic-gate 108*0Sstevel@tonic-gate was_disabled = self->ul_cancel_disabled; 109*0Sstevel@tonic-gate switch (state) { 110*0Sstevel@tonic-gate case PTHREAD_CANCEL_ENABLE: 111*0Sstevel@tonic-gate self->ul_cancel_disabled = 0; 112*0Sstevel@tonic-gate break; 113*0Sstevel@tonic-gate case PTHREAD_CANCEL_DISABLE: 114*0Sstevel@tonic-gate self->ul_cancel_disabled = 1; 115*0Sstevel@tonic-gate break; 116*0Sstevel@tonic-gate default: 117*0Sstevel@tonic-gate ulwp_unlock(self, udp); 118*0Sstevel@tonic-gate return (EINVAL); 119*0Sstevel@tonic-gate } 120*0Sstevel@tonic-gate 121*0Sstevel@tonic-gate /* 122*0Sstevel@tonic-gate * If this thread has been requested to be canceled and 123*0Sstevel@tonic-gate * is in async mode and is or was enabled, then exit. 124*0Sstevel@tonic-gate */ 125*0Sstevel@tonic-gate if ((!self->ul_cancel_disabled || !was_disabled) && 126*0Sstevel@tonic-gate self->ul_cancel_async && self->ul_cancel_pending) { 127*0Sstevel@tonic-gate ulwp_unlock(self, udp); 128*0Sstevel@tonic-gate _pthread_exit(PTHREAD_CANCELED); 129*0Sstevel@tonic-gate } 130*0Sstevel@tonic-gate 131*0Sstevel@tonic-gate ulwp_unlock(self, udp); 132*0Sstevel@tonic-gate 133*0Sstevel@tonic-gate if (oldstate != NULL) { 134*0Sstevel@tonic-gate if (was_disabled) 135*0Sstevel@tonic-gate *oldstate = PTHREAD_CANCEL_DISABLE; 136*0Sstevel@tonic-gate else 137*0Sstevel@tonic-gate *oldstate = PTHREAD_CANCEL_ENABLE; 138*0Sstevel@tonic-gate } 139*0Sstevel@tonic-gate return (0); 140*0Sstevel@tonic-gate } 141*0Sstevel@tonic-gate 142*0Sstevel@tonic-gate /* 143*0Sstevel@tonic-gate * pthread_setcanceltype: sets the type DEFERRED or ASYNCHRONOUS 144*0Sstevel@tonic-gate * If the type is being set as ASYNC, then it becomes 145*0Sstevel@tonic-gate * a cancellation point if there is a cancellation pending. 146*0Sstevel@tonic-gate */ 147*0Sstevel@tonic-gate #pragma weak pthread_setcanceltype = _pthread_setcanceltype 148*0Sstevel@tonic-gate int 149*0Sstevel@tonic-gate _pthread_setcanceltype(int type, int *oldtype) 150*0Sstevel@tonic-gate { 151*0Sstevel@tonic-gate ulwp_t *self = curthread; 152*0Sstevel@tonic-gate int was_async; 153*0Sstevel@tonic-gate 154*0Sstevel@tonic-gate /* 155*0Sstevel@tonic-gate * Call enter_critical() to defer SIGCANCEL until exit_critical(). 156*0Sstevel@tonic-gate * We do this because curthread->ul_cancel_pending is set in the 157*0Sstevel@tonic-gate * SIGCANCEL handler and we must be async-signal safe here. 158*0Sstevel@tonic-gate */ 159*0Sstevel@tonic-gate enter_critical(self); 160*0Sstevel@tonic-gate 161*0Sstevel@tonic-gate was_async = self->ul_cancel_async; 162*0Sstevel@tonic-gate switch (type) { 163*0Sstevel@tonic-gate case PTHREAD_CANCEL_ASYNCHRONOUS: 164*0Sstevel@tonic-gate self->ul_cancel_async = 1; 165*0Sstevel@tonic-gate break; 166*0Sstevel@tonic-gate case PTHREAD_CANCEL_DEFERRED: 167*0Sstevel@tonic-gate self->ul_cancel_async = 0; 168*0Sstevel@tonic-gate break; 169*0Sstevel@tonic-gate default: 170*0Sstevel@tonic-gate exit_critical(self); 171*0Sstevel@tonic-gate return (EINVAL); 172*0Sstevel@tonic-gate } 173*0Sstevel@tonic-gate self->ul_save_async = self->ul_cancel_async; 174*0Sstevel@tonic-gate 175*0Sstevel@tonic-gate /* 176*0Sstevel@tonic-gate * If this thread has been requested to be canceled and 177*0Sstevel@tonic-gate * is in enabled mode and is or was in async mode, exit. 178*0Sstevel@tonic-gate */ 179*0Sstevel@tonic-gate if ((self->ul_cancel_async || was_async) && 180*0Sstevel@tonic-gate self->ul_cancel_pending && !self->ul_cancel_disabled) { 181*0Sstevel@tonic-gate exit_critical(self); 182*0Sstevel@tonic-gate _pthread_exit(PTHREAD_CANCELED); 183*0Sstevel@tonic-gate } 184*0Sstevel@tonic-gate 185*0Sstevel@tonic-gate exit_critical(self); 186*0Sstevel@tonic-gate 187*0Sstevel@tonic-gate if (oldtype != NULL) { 188*0Sstevel@tonic-gate if (was_async) 189*0Sstevel@tonic-gate *oldtype = PTHREAD_CANCEL_ASYNCHRONOUS; 190*0Sstevel@tonic-gate else 191*0Sstevel@tonic-gate *oldtype = PTHREAD_CANCEL_DEFERRED; 192*0Sstevel@tonic-gate } 193*0Sstevel@tonic-gate return (0); 194*0Sstevel@tonic-gate } 195*0Sstevel@tonic-gate 196*0Sstevel@tonic-gate /* 197*0Sstevel@tonic-gate * pthread_testcancel: tests for any cancellation pending 198*0Sstevel@tonic-gate * if the cancellation is enabled and is pending, act on 199*0Sstevel@tonic-gate * it by calling thr_exit. thr_exit takes care of calling 200*0Sstevel@tonic-gate * cleanup handlers. 201*0Sstevel@tonic-gate */ 202*0Sstevel@tonic-gate #pragma weak _private_testcancel = _pthread_testcancel 203*0Sstevel@tonic-gate #pragma weak pthread_testcancel = _pthread_testcancel 204*0Sstevel@tonic-gate void 205*0Sstevel@tonic-gate _pthread_testcancel(void) 206*0Sstevel@tonic-gate { 207*0Sstevel@tonic-gate ulwp_t *self = curthread; 208*0Sstevel@tonic-gate 209*0Sstevel@tonic-gate if (self->ul_cancel_pending && !self->ul_cancel_disabled) 210*0Sstevel@tonic-gate _pthread_exit(PTHREAD_CANCELED); 211*0Sstevel@tonic-gate } 212*0Sstevel@tonic-gate 213*0Sstevel@tonic-gate /* 214*0Sstevel@tonic-gate * For deferred mode, this routine makes a thread cancelable. 215*0Sstevel@tonic-gate * It is called from the functions which want to be cancellation 216*0Sstevel@tonic-gate * points and are about to block, such as cond_wait(). 217*0Sstevel@tonic-gate */ 218*0Sstevel@tonic-gate void 219*0Sstevel@tonic-gate _cancelon() 220*0Sstevel@tonic-gate { 221*0Sstevel@tonic-gate ulwp_t *self = curthread; 222*0Sstevel@tonic-gate 223*0Sstevel@tonic-gate ASSERT(!(self->ul_cancelable && self->ul_cancel_disabled)); 224*0Sstevel@tonic-gate if (!self->ul_cancel_disabled) { 225*0Sstevel@tonic-gate ASSERT(self->ul_cancelable >= 0); 226*0Sstevel@tonic-gate self->ul_cancelable++; 227*0Sstevel@tonic-gate if (self->ul_cancel_pending) 228*0Sstevel@tonic-gate _pthread_exit(PTHREAD_CANCELED); 229*0Sstevel@tonic-gate } 230*0Sstevel@tonic-gate } 231*0Sstevel@tonic-gate 232*0Sstevel@tonic-gate /* 233*0Sstevel@tonic-gate * This routine turns cancelability off and possible calls pthread_exit(). 234*0Sstevel@tonic-gate * It is called from functions which are cancellation points, like cond_wait(). 235*0Sstevel@tonic-gate */ 236*0Sstevel@tonic-gate void 237*0Sstevel@tonic-gate _canceloff() 238*0Sstevel@tonic-gate { 239*0Sstevel@tonic-gate ulwp_t *self = curthread; 240*0Sstevel@tonic-gate 241*0Sstevel@tonic-gate ASSERT(!(self->ul_cancelable && self->ul_cancel_disabled)); 242*0Sstevel@tonic-gate if (!self->ul_cancel_disabled) { 243*0Sstevel@tonic-gate if (self->ul_cancel_pending) 244*0Sstevel@tonic-gate _pthread_exit(PTHREAD_CANCELED); 245*0Sstevel@tonic-gate self->ul_cancelable--; 246*0Sstevel@tonic-gate ASSERT(self->ul_cancelable >= 0); 247*0Sstevel@tonic-gate } 248*0Sstevel@tonic-gate } 249*0Sstevel@tonic-gate 250*0Sstevel@tonic-gate /* 251*0Sstevel@tonic-gate * Same as _canceloff() but don't actually cancel the thread. 252*0Sstevel@tonic-gate * This is used by cond_wait() and sema_wait() when they don't get EINTR. 253*0Sstevel@tonic-gate */ 254*0Sstevel@tonic-gate void 255*0Sstevel@tonic-gate _canceloff_nocancel() 256*0Sstevel@tonic-gate { 257*0Sstevel@tonic-gate ulwp_t *self = curthread; 258*0Sstevel@tonic-gate 259*0Sstevel@tonic-gate ASSERT(!(self->ul_cancelable && self->ul_cancel_disabled)); 260*0Sstevel@tonic-gate if (!self->ul_cancel_disabled) { 261*0Sstevel@tonic-gate self->ul_cancelable--; 262*0Sstevel@tonic-gate ASSERT(self->ul_cancelable >= 0); 263*0Sstevel@tonic-gate } 264*0Sstevel@tonic-gate } 265*0Sstevel@tonic-gate 266*0Sstevel@tonic-gate /* 267*0Sstevel@tonic-gate * __pthread_cleanup_push: called by macro in pthread.h which defines 268*0Sstevel@tonic-gate * POSIX.1c pthread_cleanup_push(). Macro in pthread.h allocates the 269*0Sstevel@tonic-gate * cleanup struct and calls this routine to push the handler off the 270*0Sstevel@tonic-gate * curthread's struct. 271*0Sstevel@tonic-gate */ 272*0Sstevel@tonic-gate void 273*0Sstevel@tonic-gate __pthread_cleanup_push(void (*routine)(void *), 274*0Sstevel@tonic-gate void *args, caddr_t fp, _cleanup_t *clnup_info) 275*0Sstevel@tonic-gate { 276*0Sstevel@tonic-gate ulwp_t *self = curthread; 277*0Sstevel@tonic-gate __cleanup_t *infop = (__cleanup_t *)clnup_info; 278*0Sstevel@tonic-gate 279*0Sstevel@tonic-gate infop->func = routine; 280*0Sstevel@tonic-gate infop->arg = args; 281*0Sstevel@tonic-gate infop->fp = fp; 282*0Sstevel@tonic-gate infop->next = self->ul_clnup_hdr; 283*0Sstevel@tonic-gate self->ul_clnup_hdr = infop; 284*0Sstevel@tonic-gate } 285*0Sstevel@tonic-gate 286*0Sstevel@tonic-gate /* 287*0Sstevel@tonic-gate * __pthread_cleanup_pop: called by macro in pthread.h which defines 288*0Sstevel@tonic-gate * POSIX.1c pthread_cleanup_pop(). It calls this routine to pop the 289*0Sstevel@tonic-gate * handler off the curthread's struct and execute it if necessary. 290*0Sstevel@tonic-gate */ 291*0Sstevel@tonic-gate /* ARGSUSED1 */ 292*0Sstevel@tonic-gate void 293*0Sstevel@tonic-gate __pthread_cleanup_pop(int ex, _cleanup_t *clnup_info) 294*0Sstevel@tonic-gate { 295*0Sstevel@tonic-gate ulwp_t *self = curthread; 296*0Sstevel@tonic-gate __cleanup_t *infop = self->ul_clnup_hdr; 297*0Sstevel@tonic-gate 298*0Sstevel@tonic-gate self->ul_clnup_hdr = infop->next; 299*0Sstevel@tonic-gate if (ex) 300*0Sstevel@tonic-gate (*infop->func)(infop->arg); 301*0Sstevel@tonic-gate } 302