lib/libkse/thread/thr_sig.c

   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  * $FreeBSD$
  33  */
  34 #include <sys/param.h>
  35 #include <sys/types.h>
  36 #include <sys/signalvar.h>
  37 #include <signal.h>
  38 #include <errno.h>
  39 #include <fcntl.h>
  40 #include <unistd.h>
  41 #include <string.h>
  42 #include <pthread.h>
  43 #include "thr_private.h"
  44
  45 /* Prototypes: */
  46 static inline void build_siginfo(siginfo_t *info, int signo);
  47 #ifndef SYSTEM_SCOPE_ONLY
  48 static struct pthread *thr_sig_find(struct kse *curkse, int sig,
  49                     siginfo_t *info);
  50 #endif
  51 static inline void thr_sigframe_restore(struct pthread *thread,
  52         struct pthread_sigframe *psf);
  53 static inline void thr_sigframe_save(struct pthread *thread,
  54         struct pthread_sigframe *psf);
  55
  56 #define SA_KILL         0x01            /* terminates process by default */
  57 #define SA_STOP         0x02
  58 #define SA_CONT         0x04
  59
  60 static int sigproptbl[NSIG] = {
  61         SA_KILL,        /* SIGHUP */
  62         SA_KILL,        /* SIGINT */
  63         SA_KILL,        /* SIGQUIT */
  64         SA_KILL,        /* SIGILL */
  65         SA_KILL,        /* SIGTRAP */
  66         SA_KILL,        /* SIGABRT */
  67         SA_KILL,        /* SIGEMT */
  68         SA_KILL,        /* SIGFPE */
  69         SA_KILL,        /* SIGKILL */
  70         SA_KILL,        /* SIGBUS */
  71         SA_KILL,        /* SIGSEGV */
  72         SA_KILL,        /* SIGSYS */
  73         SA_KILL,        /* SIGPIPE */
  74         SA_KILL,        /* SIGALRM */
  75         SA_KILL,        /* SIGTERM */
  76         0,              /* SIGURG */
  77         SA_STOP,        /* SIGSTOP */
  78         SA_STOP,        /* SIGTSTP */
  79         SA_CONT,        /* SIGCONT */
  80         0,              /* SIGCHLD */
  81         SA_STOP,        /* SIGTTIN */
  82         SA_STOP,        /* SIGTTOU */
  83         0,              /* SIGIO */
  84         SA_KILL,        /* SIGXCPU */
  85         SA_KILL,        /* SIGXFSZ */
  86         SA_KILL,        /* SIGVTALRM */
  87         SA_KILL,        /* SIGPROF */
  88         0,              /* SIGWINCH  */
  89         0,              /* SIGINFO */
  90         SA_KILL,        /* SIGUSR1 */
  91         SA_KILL         /* SIGUSR2 */
  92 };
  93
  94 /* #define DEBUG_SIGNAL */
  95 #ifdef DEBUG_SIGNAL
  96 #define DBG_MSG         stdout_debug
  97 #else
  98 #define DBG_MSG(x...)
  99 #endif
 100
 101 /*
 102  * Signal setup and delivery.
 103  *
 104  * 1) Delivering signals to threads in the same KSE.
 105  *    These signals are sent by upcall events and are set in the
 106  *    km_sigscaught field of the KSE mailbox.  Since these signals
 107  *    are received while operating on the KSE stack, they can be
 108  *    delivered either by using signalcontext() to add a stack frame
 109  *    to the target thread's stack, or by adding them in the thread's
 110  *    pending set and having the thread run them down after it
 111  * 2) Delivering signals to threads in other KSEs/KSEGs.
 112  * 3) Delivering signals to threads in critical regions.
 113  * 4) Delivering signals to threads after they change their signal masks.
 114  *
 115  * Methods of delivering signals.
 116  *
 117  *   1) Add a signal frame to the thread's saved context.
 118  *   2) Add the signal to the thread structure, mark the thread as
 119  *      having signals to handle, and let the thread run them down
 120  *      after it resumes from the KSE scheduler.
 121  *
 122  * Problem with 1).  You can't do this to a running thread or a
 123  * thread in a critical region.
 124  *
 125  * Problem with 2).  You can't do this to a thread that doesn't
 126  * yield in some way (explicitly enters the scheduler).  A thread
 127  * blocked in the kernel or a CPU hungry thread will not see the
 128  * signal without entering the scheduler.
 129  *
 130  * The solution is to use both 1) and 2) to deliver signals:
 131  *
 132  *   o Thread in critical region - use 2).  When the thread
 133  *     leaves the critical region it will check to see if it
 134  *     has pending signals and run them down.
 135  *
 136  *   o Thread enters scheduler explicitly - use 2).  The thread
 137  *     can check for pending signals after it returns from the
 138  *     the scheduler.
 139  *
 140  *   o Thread is running and not current thread - use 2).  When the
 141  *     thread hits a condition specified by one of the other bullets,
 142  *     the signal will be delivered.
 143  *
 144  *   o Thread is running and is current thread (e.g., the thread
 145  *     has just changed its signal mask and now sees that it has
 146  *     pending signals) - just run down the pending signals.
 147  *
 148  *   o Thread is swapped out due to quantum expiration - use 1)
 149  *
 150  *   o Thread is blocked in kernel - kse_thr_wakeup() and then
 151  *     use 1)
 152  */
 153
 154 /*
 155  * Rules for selecting threads for signals received:
 156  *
 157  *   1) If the signal is a sychronous signal, it is delivered to
 158  *      the generating (current thread).  If the thread has the
 159  *      signal masked, it is added to the threads pending signal
 160  *      set until the thread unmasks it.
 161  *
 162  *   2) A thread in sigwait() where the signal is in the thread's
 163  *      waitset.
 164  *
 165  *   3) A thread in sigsuspend() where the signal is not in the
 166  *      thread's suspended signal mask.
 167  *
 168  *   4) Any thread (first found/easiest to deliver) that has the
 169  *      signal unmasked.
 170  */
 171
 172 #ifndef SYSTEM_SCOPE_ONLY
 173
 174 static void *
 175 sig_daemon(void *arg /* Unused */)
 176 {
 177         int i;
 178         kse_critical_t crit;
 179         struct timespec ts;
 180         sigset_t set;
 181         struct kse *curkse;
 182         struct pthread *curthread = _get_curthread();
 183
 184         DBG_MSG("signal daemon started(%p)\n", curthread);
 185
 186         curthread->name = strdup("signal thread");
 187         crit = _kse_critical_enter();
 188         curkse = _get_curkse();
 189
 190         /*
 191          * Daemon thread is a bound thread and we must be created with
 192          * all signals masked
 193          */
 194 #if 0
 195         SIGFILLSET(set);
 196         __sys_sigprocmask(SIG_SETMASK, &set, NULL);
 197 #endif
 198         __sys_sigpending(&set);
 199         ts.tv_sec = 0;
 200         ts.tv_nsec = 0;
 201         while (1) {
 202                 KSE_LOCK_ACQUIRE(curkse, &_thread_signal_lock);
 203                 _thr_proc_sigpending = set;
 204                 KSE_LOCK_RELEASE(curkse, &_thread_signal_lock);
 205                 for (i = 1; i <= _SIG_MAXSIG; i++) {
 206                         if (SIGISMEMBER(set, i) != 0)
 207                                 _thr_sig_dispatch(curkse, i,
 208                                     NULL /* no siginfo */);
 209                 }
 210                 ts.tv_sec = 30;
 211                 ts.tv_nsec = 0;
 212                 curkse->k_kcb->kcb_kmbx.km_flags =
 213                     KMF_NOUPCALL | KMF_NOCOMPLETED | KMF_WAITSIGEVENT;
 214                 kse_release(&ts);
 215                 curkse->k_kcb->kcb_kmbx.km_flags = 0;
 216                 set = curkse->k_kcb->kcb_kmbx.km_sigscaught;
 217         }
 218         return (0);
 219 }
 220
 221
 222 /* Utility function to create signal daemon thread */
 223 int
 224 _thr_start_sig_daemon(void)
 225 {
 226         pthread_attr_t attr;
 227         sigset_t sigset, oldset;
 228
 229         SIGFILLSET(sigset);
 230         pthread_sigmask(SIG_SETMASK, &sigset, &oldset);
 231         pthread_attr_init(&attr);
 232         pthread_attr_setscope(&attr, PTHREAD_SCOPE_SYSTEM);
 233         attr->flags |= THR_SIGNAL_THREAD;
 234         /* sigmask will be inherited */
 235         if (pthread_create(&_thr_sig_daemon, &attr, sig_daemon, NULL))
 236                 PANIC("can not create signal daemon thread!\n");
 237         pthread_attr_destroy(&attr);
 238         pthread_sigmask(SIG_SETMASK, &oldset, NULL);
 239         return (0);
 240 }
 241
 242 /*
 243  * This signal handler only delivers asynchronous signals.
 244  * This must be called with upcalls disabled and without
 245  * holding any locks.
 246  */
 247 void
 248 _thr_sig_dispatch(struct kse *curkse, int sig, siginfo_t *info)
 249 {
 250         struct kse_mailbox *kmbx;
 251         struct pthread *thread;
 252
 253         DBG_MSG(">>> _thr_sig_dispatch(%d)\n", sig);
 254
 255         /* Check if the signal requires a dump of thread information: */
 256         if (sig == SIGINFO) {
 257                 /* Dump thread information to file: */
 258                 _thread_dump_info();
 259         }
 260
 261         while ((thread = thr_sig_find(curkse, sig, info)) != NULL) {
 262                 /*
 263                  * Setup the target thread to receive the signal:
 264                  */
 265                 DBG_MSG("Got signal %d, selecting thread %p\n", sig, thread);
 266                 KSE_SCHED_LOCK(curkse, thread->kseg);
 267                 if ((thread->state == PS_DEAD) ||
 268                     (thread->state == PS_DEADLOCK) ||
 269                     THR_IS_EXITING(thread) || THR_IS_SUSPENDED(thread)) {
 270                         KSE_SCHED_UNLOCK(curkse, thread->kseg);
 271                         _thr_ref_delete(NULL, thread);
 272                 } else if (SIGISMEMBER(thread->sigmask, sig)) {
 273                         KSE_SCHED_UNLOCK(curkse, thread->kseg);
 274                         _thr_ref_delete(NULL, thread);
 275                 } else {
 276                         kmbx = _thr_sig_add(thread, sig, info);
 277                         KSE_SCHED_UNLOCK(curkse, thread->kseg);
 278                         _thr_ref_delete(NULL, thread);
 279                         if (kmbx != NULL)
 280                                 kse_wakeup(kmbx);
 281                         break;
 282                 }
 283         }
 284         DBG_MSG("<<< _thr_sig_dispatch\n");
 285 }
 286
 287 #endif /* ! SYSTEM_SCOPE_ONLY */
 288
 289 static __inline int
 290 sigprop(int sig)
 291 {
 292
 293         if (sig > 0 && sig < NSIG)
 294                 return (sigproptbl[_SIG_IDX(sig)]);
 295         return (0);
 296 }
 297
 298 typedef void (*ohandler)(int sig, int code,
 299         struct sigcontext *scp, char *addr, __sighandler_t *catcher);
 300
 301 void
 302 _thr_sig_handler(int sig, siginfo_t *info, ucontext_t *ucp)
 303 {
 304         struct pthread_sigframe psf;
 305         __siginfohandler_t *sigfunc;
 306         struct pthread *curthread;
 307         struct kse *curkse;
 308         struct sigaction act;
 309         int sa_flags, err_save;
 310
 311         err_save = errno;
 312
 313         DBG_MSG(">>> _thr_sig_handler(%d)\n", sig);
 314
 315         curthread = _get_curthread();
 316         if (curthread == NULL)
 317                 PANIC("No current thread.\n");
 318         if (!(curthread->attr.flags & PTHREAD_SCOPE_SYSTEM))
 319                 PANIC("Thread is not system scope.\n");
 320         if (curthread->flags & THR_FLAGS_EXITING) {
 321                 errno = err_save;
 322                 return;
 323         }
 324
 325         curkse = _get_curkse();
 326         /*
 327          * If thread is in critical region or if thread is on
 328          * the way of state transition, then latch signal into buffer.
 329          */
 330         if (_kse_in_critical() || THR_IN_CRITICAL(curthread) ||
 331             curthread->state != PS_RUNNING) {
 332                 DBG_MSG(">>> _thr_sig_handler(%d) in critical\n", sig);
 333                 curthread->siginfo[sig-1] = *info;
 334                 curthread->check_pending = 1;
 335                 curkse->k_sigseqno++;
 336                 SIGADDSET(curthread->sigpend, sig);
 337                 /*
 338                  * If the kse is on the way to idle itself, but
 339                  * we have signal ready, we should prevent it
 340                  * to sleep, kernel will latch the wakeup request,
 341                  * so kse_release will return from kernel immediately.
 342                  */
 343                 if (KSE_IS_IDLE(curkse))
 344                         kse_wakeup(&curkse->k_kcb->kcb_kmbx);
 345                 errno = err_save;
 346                 return;
 347         }
 348
 349         /* Check if the signal requires a dump of thread information: */
 350         if (sig == SIGINFO) {
 351                 /* Dump thread information to file: */
 352                 _thread_dump_info();
 353         }
 354
 355         /* Check the threads previous state: */
 356         curthread->critical_count++;
 357         if (curthread->sigbackout != NULL)
 358                 curthread->sigbackout((void *)curthread);
 359         curthread->critical_count--;
 360         thr_sigframe_save(curthread, &psf);
 361         THR_ASSERT(!(curthread->sigbackout), "sigbackout was not cleared.");
 362
 363         _kse_critical_enter();
 364         /* Get a fresh copy of signal mask */
 365         __sys_sigprocmask(SIG_BLOCK, NULL, &curthread->sigmask);
 366         KSE_LOCK_ACQUIRE(curkse, &_thread_signal_lock);
 367         sigfunc = _thread_sigact[sig - 1].sa_sigaction;
 368         sa_flags = _thread_sigact[sig - 1].sa_flags;
 369         if (sa_flags & SA_RESETHAND) {
 370                 act.sa_handler = SIG_DFL;
 371                 act.sa_flags = SA_RESTART;
 372                 SIGEMPTYSET(act.sa_mask);
 373                 __sys_sigaction(sig, &act, NULL);
 374                 __sys_sigaction(sig, NULL, &_thread_sigact[sig - 1]);
 375         }
 376         KSE_LOCK_RELEASE(curkse, &_thread_signal_lock);
 377         _kse_critical_leave(&curthread->tcb->tcb_tmbx);
 378
 379         /* Now invoke real handler */
 380         if (((__sighandler_t *)sigfunc != SIG_DFL) &&
 381             ((__sighandler_t *)sigfunc != SIG_IGN) &&
 382             (sigfunc != (__siginfohandler_t *)_thr_sig_handler)) {
 383                 if ((sa_flags & SA_SIGINFO) != 0 || info == NULL)
 384                         (*(sigfunc))(sig, info, ucp);
 385                 else {
 386                         ((ohandler)(*sigfunc))(
 387                                 sig, info->si_code, (struct sigcontext *)ucp,
 388                                 info->si_addr, (__sighandler_t *)sigfunc);
 389                 }
 390         } else {
 391                 if ((__sighandler_t *)sigfunc == SIG_DFL) {
 392                         if (sigprop(sig) & SA_KILL) {
 393                                 if (_kse_isthreaded())
 394                                         kse_thr_interrupt(NULL,
 395                                                  KSE_INTR_SIGEXIT, sig);
 396                                 else
 397                                         kill(getpid(), sig);
 398                         }
 399 #ifdef NOTYET
 400                         else if (sigprop(sig) & SA_STOP)
 401                                 kse_thr_interrupt(NULL, KSE_INTR_JOBSTOP, sig);
 402 #endif
 403                 }
 404         }
 405         _kse_critical_enter();
 406         curthread->sigmask = ucp->uc_sigmask;
 407         SIG_CANTMASK(curthread->sigmask);
 408         _kse_critical_leave(&curthread->tcb->tcb_tmbx);
 409
 410         thr_sigframe_restore(curthread, &psf);
 411
 412         DBG_MSG("<<< _thr_sig_handler(%d)\n", sig);
 413
 414         errno = err_save;
 415 }
 416
 417 struct sighandle_info {
 418         __siginfohandler_t *sigfunc;
 419         int sa_flags;
 420         int sig;
 421         siginfo_t *info;
 422         ucontext_t *ucp;
 423 };
 424
 425 static void handle_signal(struct pthread *curthread,
 426         struct sighandle_info *shi);
 427 static void handle_signal_altstack(struct pthread *curthread,
 428         struct sighandle_info *shi);
 429
 430 /* Must be called with signal lock and schedule lock held in order */
 431 static void
 432 thr_sig_invoke_handler(struct pthread *curthread, int sig, siginfo_t *info,
 433     ucontext_t *ucp)
 434 {
 435         __siginfohandler_t *sigfunc;
 436         sigset_t sigmask;
 437         int sa_flags;
 438         int onstack;
 439         struct sigaction act;
 440         struct kse *curkse;
 441         struct sighandle_info shi;
 442
 443         /*
 444          * Invoke the signal handler without going through the scheduler:
 445          */
 446         DBG_MSG("Got signal %d, calling handler for current thread %p\n",
 447             sig, curthread);
 448
 449         if (!_kse_in_critical())
 450                 PANIC("thr_sig_invoke_handler without in critical\n");
 451         curkse = curthread->kse;
 452         /*
 453          * Check that a custom handler is installed and if
 454          * the signal is not blocked:
 455          */
 456         sigfunc = _thread_sigact[sig - 1].sa_sigaction;
 457         sa_flags = _thread_sigact[sig - 1].sa_flags;
 458         sigmask = curthread->sigmask;
 459         SIGSETOR(curthread->sigmask, _thread_sigact[sig - 1].sa_mask);
 460         if (!(sa_flags & (SA_NODEFER | SA_RESETHAND)))
 461                 SIGADDSET(curthread->sigmask, sig);
 462         if ((sig != SIGILL) && (sa_flags & SA_RESETHAND)) {
 463                 act.sa_handler = SIG_DFL;
 464                 act.sa_flags = SA_RESTART;
 465                 SIGEMPTYSET(act.sa_mask);
 466                 __sys_sigaction(sig, &act, NULL);
 467                 __sys_sigaction(sig, NULL, &_thread_sigact[sig - 1]);
 468         }
 469         KSE_LOCK_RELEASE(curkse, &_thread_signal_lock);
 470         KSE_SCHED_UNLOCK(curkse, curkse->k_kseg);
 471         /*
 472          * We are processing buffered signals, synchronize working
 473          * signal mask into kernel.
 474          */
 475         if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM)
 476                 __sys_sigprocmask(SIG_SETMASK, &curthread->sigmask, NULL);
 477         onstack = _thr_sigonstack(&sigfunc);
 478         ucp->uc_stack = curthread->sigstk;
 479         ucp->uc_stack.ss_flags = (curthread->sigstk.ss_flags & SS_DISABLE)
 480                 ? SS_DISABLE : ((onstack) ? SS_ONSTACK : 0);
 481         if (curthread->oldsigmask) {
 482                 ucp->uc_sigmask = *(curthread->oldsigmask);
 483                 curthread->oldsigmask = NULL;
 484         } else
 485                 ucp->uc_sigmask = sigmask;
 486         shi.sigfunc = sigfunc;
 487         shi.sig = sig;
 488         shi.sa_flags = sa_flags;
 489         shi.info = info;
 490         shi.ucp = ucp;
 491         if ((curthread->sigstk.ss_flags & SS_DISABLE) == 0) {
 492                 /* Deliver signal on alternative stack */
 493                 if (sa_flags & SA_ONSTACK && !onstack)
 494                         handle_signal_altstack(curthread, &shi);
 495                 else
 496                         handle_signal(curthread, &shi);
 497         } else {
 498                 handle_signal(curthread, &shi);
 499         }
 500
 501         _kse_critical_enter();
 502         /* Don't trust after critical leave/enter */
 503         curkse = curthread->kse;
 504
 505         /*
 506          * Restore the thread's signal mask.
 507          */
 508         curthread->sigmask = ucp->uc_sigmask;
 509         SIG_CANTMASK(curthread->sigmask);
 510         if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM)
 511                 __sys_sigprocmask(SIG_SETMASK, &ucp->uc_sigmask, NULL);
 512         KSE_SCHED_LOCK(curkse, curkse->k_kseg);
 513         KSE_LOCK_ACQUIRE(curkse, &_thread_signal_lock);
 514
 515         DBG_MSG("Got signal %d, handler returned %p\n", sig, curthread);
 516 }
 517
 518 static void
 519 handle_signal(struct pthread *curthread, struct sighandle_info *shi)
 520 {
 521         _kse_critical_leave(&curthread->tcb->tcb_tmbx);
 522
 523         /* Check if the signal requires a dump of thread information: */
 524         if (shi->sig == SIGINFO) {
 525                 /* Dump thread information to file: */
 526                 _thread_dump_info();
 527         }
 528
 529         if (((__sighandler_t *)shi->sigfunc != SIG_DFL) &&
 530             ((__sighandler_t *)shi->sigfunc != SIG_IGN)) {
 531                 if ((shi->sa_flags & SA_SIGINFO) != 0 || shi->info == NULL)
 532                         (*(shi->sigfunc))(shi->sig, shi->info, shi->ucp);
 533                 else {
 534                         ((ohandler)(*shi->sigfunc))(
 535                                 shi->sig, shi->info->si_code,
 536                                 (struct sigcontext *)shi->ucp,
 537                                 shi->info->si_addr,
 538                                 (__sighandler_t *)shi->sigfunc);
 539                 }
 540         } else {
 541                 if ((__sighandler_t *)shi->sigfunc == SIG_DFL) {
 542                         if (sigprop(shi->sig) & SA_KILL) {
 543                                 if (_kse_isthreaded())
 544                                         kse_thr_interrupt(NULL,
 545                                                  KSE_INTR_SIGEXIT, shi->sig);
 546                                 else
 547                                         kill(getpid(), shi->sig);
 548                         }
 549 #ifdef NOTYET
 550                         else if (sigprop(shi->sig) & SA_STOP)
 551                                 kse_thr_interrupt(NULL, KSE_INTR_JOBSTOP,
 552                                         shi->sig);
 553 #endif
 554                 }
 555         }
 556 }
 557
 558 static void
 559 handle_signal_wrapper(struct pthread *curthread, ucontext_t *ret_uc,
 560         struct sighandle_info *shi)
 561 {
 562         shi->ucp->uc_stack.ss_flags = SS_ONSTACK;
 563         handle_signal(curthread, shi);
 564         if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM)
 565                 setcontext(ret_uc);
 566         else {
 567                 /* Work around for ia64, THR_SETCONTEXT does not work */
 568                 _kse_critical_enter();
 569                 curthread->tcb->tcb_tmbx.tm_context = *ret_uc;
 570                 _thread_switch(curthread->kse->k_kcb, curthread->tcb, 1);
 571                 /* THR_SETCONTEXT */
 572         }
 573 }
 574
 575 /*
 576  * Jump to stack set by sigaltstack before invoking signal handler
 577  */
 578 static void
 579 handle_signal_altstack(struct pthread *curthread, struct sighandle_info *shi)
 580 {
 581         volatile int once;
 582         ucontext_t uc1, *uc2;
 583
 584         THR_ASSERT(_kse_in_critical(), "Not in critical");
 585
 586         once = 0;
 587         THR_GETCONTEXT(&uc1);
 588         if (once == 0) {
 589                 once = 1;
 590                 /* XXX
 591                  * We are still in critical region, it is safe to operate thread
 592                  * context
 593                  */
 594                 uc2 = &curthread->tcb->tcb_tmbx.tm_context;
 595                 uc2->uc_stack = curthread->sigstk;
 596                 makecontext(uc2, (void (*)(void))handle_signal_wrapper,
 597                         3, curthread, &uc1, shi);
 598                 if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM)
 599                         setcontext(uc2);
 600                 else {
 601                         _thread_switch(curthread->kse->k_kcb, curthread->tcb, 1);
 602                         /* THR_SETCONTEXT(uc2); */
 603                 }
 604         }
 605 }
 606
 607 int
 608 _thr_getprocsig(int sig, siginfo_t *siginfo)
 609 {
 610         kse_critical_t crit;
 611         struct kse *curkse;
 612         int ret;
 613
 614         DBG_MSG(">>> _thr_getprocsig\n");
 615
 616         crit = _kse_critical_enter();
 617         curkse = _get_curkse();
 618         KSE_LOCK_ACQUIRE(curkse, &_thread_signal_lock);
 619         ret = _thr_getprocsig_unlocked(sig, siginfo);
 620         KSE_LOCK_RELEASE(curkse, &_thread_signal_lock);
 621         _kse_critical_leave(crit);
 622
 623         DBG_MSG("<<< _thr_getprocsig\n");
 624         return (ret);
 625 }
 626
 627 int
 628 _thr_getprocsig_unlocked(int sig, siginfo_t *siginfo)
 629 {
 630         sigset_t sigset;
 631         struct timespec ts;
 632
 633         /* try to retrieve signal from kernel */
 634         SIGEMPTYSET(sigset);
 635         SIGADDSET(sigset, sig);
 636         ts.tv_sec = 0;
 637         ts.tv_nsec = 0;
 638         SIGDELSET(_thr_proc_sigpending, sig);
 639         if (__sys_sigtimedwait(&sigset, siginfo, &ts) > 0)
 640                 return (sig);
 641         return (0);
 642 }
 643
 644 #ifndef SYSTEM_SCOPE_ONLY
 645 /*
 646  * Find a thread that can handle the signal.  This must be called
 647  * with upcalls disabled.
 648  */
 649 struct pthread *
 650 thr_sig_find(struct kse *curkse, int sig, siginfo_t *info)
 651 {
 652         struct kse_mailbox *kmbx = NULL;
 653         struct pthread  *pthread;
 654         struct pthread  *suspended_thread, *signaled_thread;
 655         __siginfohandler_t *sigfunc;
 656         siginfo_t si;
 657
 658         DBG_MSG("Looking for thread to handle signal %d\n", sig);
 659
 660         /*
 661          * Enter a loop to look for threads that have the signal
 662          * unmasked.  POSIX specifies that a thread in a sigwait
 663          * will get the signal over any other threads.  Second
 664          * preference will be threads in in a sigsuspend.  Third
 665          * preference will be the current thread.  If none of the
 666          * above, then the signal is delivered to the first thread
 667          * that is found.  Note that if a custom handler is not
 668          * installed, the signal only affects threads in sigwait.
 669          */
 670         suspended_thread = NULL;
 671         signaled_thread = NULL;
 672
 673         KSE_LOCK_ACQUIRE(curkse, &_thread_list_lock);
 674         TAILQ_FOREACH(pthread, &_thread_list, tle) {
 675                 if (pthread == _thr_sig_daemon)
 676                         continue;
 677                 /* Signal delivering to bound thread is done by kernel */
 678                 if (pthread->attr.flags & PTHREAD_SCOPE_SYSTEM)
 679                         continue;
 680                 /* Take the scheduling lock. */
 681                 KSE_SCHED_LOCK(curkse, pthread->kseg);
 682                 if ((pthread->state == PS_DEAD)         ||
 683                     (pthread->state == PS_DEADLOCK)     ||
 684                     THR_IS_EXITING(pthread)             ||
 685                     THR_IS_SUSPENDED(pthread)) {
 686                         ; /* Skip this thread. */
 687                 } else if (pthread->state == PS_SIGWAIT &&
 688                            SIGISMEMBER(*(pthread->data.sigwait->waitset), sig)) {
 689                         /*
 690                          * retrieve signal from kernel, if it is job control
 691                          * signal, and sigaction is SIG_DFL, then we will
 692                          * be stopped in kernel, we hold lock here, but that
 693                          * does not matter, because that's job control, and
 694                          * whole process should be stopped.
 695                          */
 696                         if (_thr_getprocsig(sig, &si)) {
 697                                 DBG_MSG("Waking thread %p in sigwait"
 698                                         " with signal %d\n", pthread, sig);
 699                                 /*  where to put siginfo ? */
 700                                 *(pthread->data.sigwait->siginfo) = si;
 701                                 kmbx = _thr_setrunnable_unlocked(pthread);
 702                         }
 703                         KSE_SCHED_UNLOCK(curkse, pthread->kseg);
 704                         /*
 705                          * POSIX doesn't doesn't specify which thread
 706                          * will get the signal if there are multiple
 707                          * waiters, so we give it to the first thread
 708                          * we find.
 709                          *
 710                          * Do not attempt to deliver this signal
 711                          * to other threads and do not add the signal
 712                          * to the process pending set.
 713                          */
 714                         KSE_LOCK_RELEASE(curkse, &_thread_list_lock);
 715                         if (kmbx != NULL)
 716                                 kse_wakeup(kmbx);
 717                         if (suspended_thread != NULL)
 718                                 _thr_ref_delete(NULL, suspended_thread);
 719                         if (signaled_thread != NULL)
 720                                 _thr_ref_delete(NULL, signaled_thread);
 721                         return (NULL);
 722                 } else if (!SIGISMEMBER(pthread->sigmask, sig)) {
 723                         /*
 724                          * If debugger is running, we don't quick exit,
 725                          * and give it a chance to check the signal.
 726                          */
 727                         if (_libkse_debug == 0) {
 728                                 sigfunc = _thread_sigact[sig - 1].sa_sigaction;
 729                                 if ((__sighandler_t *)sigfunc == SIG_DFL) {
 730                                         if (sigprop(sig) & SA_KILL) {
 731                                                 kse_thr_interrupt(NULL,
 732                                                          KSE_INTR_SIGEXIT, sig);
 733                                                 /* Never reach */
 734                                         }
 735                                 }
 736                         }
 737                         if (pthread->state == PS_SIGSUSPEND) {
 738                                 if (suspended_thread == NULL) {
 739                                         suspended_thread = pthread;
 740                                         suspended_thread->refcount++;
 741                                 }
 742                         } else if (signaled_thread == NULL) {
 743                                 signaled_thread = pthread;
 744                                 signaled_thread->refcount++;
 745                         }
 746                 }
 747                 KSE_SCHED_UNLOCK(curkse, pthread->kseg);
 748         }
 749         KSE_LOCK_RELEASE(curkse, &_thread_list_lock);
 750
 751         if (suspended_thread != NULL) {
 752                 pthread = suspended_thread;
 753                 if (signaled_thread)
 754                         _thr_ref_delete(NULL, signaled_thread);
 755         } else if (signaled_thread) {
 756                 pthread = signaled_thread;
 757         } else {
 758                 pthread = NULL;
 759         }
 760         return (pthread);
 761 }
 762 #endif /* ! SYSTEM_SCOPE_ONLY */
 763
 764 static inline void
 765 build_siginfo(siginfo_t *info, int signo)
 766 {
 767         bzero(info, sizeof(*info));
 768         info->si_signo = signo;
 769         info->si_pid = _thr_pid;
 770 }
 771
 772 /*
 773  * This is called by a thread when it has pending signals to deliver.
 774  * It should only be called from the context of the thread.
 775  */
 776 void
 777 _thr_sig_rundown(struct pthread *curthread, ucontext_t *ucp)
 778 {
 779         struct pthread_sigframe psf;
 780         siginfo_t siginfo;
 781         int i, err_save;
 782         kse_critical_t crit;
 783         struct kse *curkse;
 784         sigset_t sigmask;
 785
 786         err_save = errno;
 787
 788         DBG_MSG(">>> thr_sig_rundown (%p)\n", curthread);
 789
 790         /* Check the threads previous state: */
 791         curthread->critical_count++;
 792         if (curthread->sigbackout != NULL)
 793                 curthread->sigbackout((void *)curthread);
 794         curthread->critical_count--;
 795
 796         THR_ASSERT(!(curthread->sigbackout), "sigbackout was not cleared.");
 797         THR_ASSERT((curthread->state == PS_RUNNING), "state is not PS_RUNNING");
 798
 799         thr_sigframe_save(curthread, &psf);
 800         /*
 801          * Lower the priority before calling the handler in case
 802          * it never returns (longjmps back):
 803          */
 804         crit = _kse_critical_enter();
 805         curkse = curthread->kse;
 806         KSE_SCHED_LOCK(curkse, curkse->k_kseg);
 807         KSE_LOCK_ACQUIRE(curkse, &_thread_signal_lock);
 808         curthread->active_priority &= ~THR_SIGNAL_PRIORITY;
 809         SIGFILLSET(sigmask);
 810         while (1) {
 811                 /*
 812                  * For bound thread, we mask all signals and get a fresh
 813                  * copy of signal mask from kernel
 814                  */
 815                 if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM) {
 816                         __sys_sigprocmask(SIG_SETMASK, &sigmask,
 817                                  &curthread->sigmask);
 818                 }
 819                 for (i = 1; i <= _SIG_MAXSIG; i++) {
 820                         if (SIGISMEMBER(curthread->sigmask, i))
 821                                 continue;
 822                         if (SIGISMEMBER(curthread->sigpend, i)) {
 823                                 SIGDELSET(curthread->sigpend, i);
 824                                 siginfo = curthread->siginfo[i-1];
 825                                 break;
 826                         }
 827                         if (!(curthread->attr.flags & PTHREAD_SCOPE_SYSTEM)
 828                             && SIGISMEMBER(_thr_proc_sigpending, i)) {
 829                                 if (_thr_getprocsig_unlocked(i, &siginfo))
 830                                         break;
 831                         }
 832                 }
 833                 if (i <= _SIG_MAXSIG)
 834                         thr_sig_invoke_handler(curthread, i, &siginfo, ucp);
 835                 else {
 836                         if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM) {
 837                                 __sys_sigprocmask(SIG_SETMASK,
 838                                                  &curthread->sigmask, NULL);
 839                         }
 840                         break;
 841                 }
 842         }
 843
 844         /* Don't trust after signal handling */
 845         curkse = curthread->kse;
 846         KSE_LOCK_RELEASE(curkse, &_thread_signal_lock);
 847         KSE_SCHED_UNLOCK(curkse, curkse->k_kseg);
 848         _kse_critical_leave(&curthread->tcb->tcb_tmbx);
 849         /* repost masked signal to kernel, it hardly happens in real world */
 850         if ((curthread->attr.flags & PTHREAD_SCOPE_SYSTEM) &&
 851             !SIGISEMPTY(curthread->sigpend)) { /* dirty read */
 852                 __sys_sigprocmask(SIG_SETMASK, &sigmask, &curthread->sigmask);
 853                 for (i = 1; i <= _SIG_MAXSIG; ++i) {
 854                         if (SIGISMEMBER(curthread->sigpend, i)) {
 855                                 SIGDELSET(curthread->sigpend, i);
 856                                 if (!_kse_isthreaded())
 857                                         kill(getpid(), i);
 858                                 else
 859                                         kse_thr_interrupt(
 860                                                 &curthread->tcb->tcb_tmbx,
 861                                                 KSE_INTR_SENDSIG,
 862                                                 i);
 863                         }
 864                 }
 865                 __sys_sigprocmask(SIG_SETMASK, &curthread->sigmask, NULL);
 866         }
 867         DBG_MSG("<<< thr_sig_rundown (%p)\n", curthread);
 868
 869         thr_sigframe_restore(curthread, &psf);
 870         errno = err_save;
 871 }
 872
 873 /*
 874  * This checks pending signals for the current thread.  It should be
 875  * called whenever a thread changes its signal mask.  Note that this
 876  * is called from a thread (using its stack).
 877  *
 878  * XXX - We might want to just check to see if there are pending
 879  *       signals for the thread here, but enter the UTS scheduler
 880  *       to actually install the signal handler(s).
 881  */
 882 void
 883 _thr_sig_check_pending(struct pthread *curthread)
 884 {
 885         ucontext_t uc;
 886         volatile int once;
 887         int errsave;
 888
 889         /*
 890          * If the thread is in critical region, delay processing signals.
 891          * If the thread state is not PS_RUNNING, it might be switching
 892          * into UTS and but a THR_LOCK_RELEASE saw check_pending, and it
 893          * goes here, in the case we delay processing signals, lets UTS
 894          * process complicated things, normally UTS will call _thr_sig_add
 895          * to resume the thread, so we needn't repeat doing it here.
 896          */
 897         if (THR_IN_CRITICAL(curthread) || curthread->state != PS_RUNNING)
 898                 return;
 899
 900         errsave = errno;
 901         once = 0;
 902         THR_GETCONTEXT(&uc);
 903         if (once == 0) {
 904                 once = 1;
 905                 curthread->check_pending = 0;
 906                 _thr_sig_rundown(curthread, &uc);
 907         }
 908         errno = errsave;
 909 }
 910
 911 /*
 912  * Perform thread specific actions in response to a signal.
 913  * This function is only called if there is a handler installed
 914  * for the signal, and if the target thread has the signal
 915  * unmasked.
 916  *
 917  * This must be called with the thread's scheduling lock held.
 918  */
 919 struct kse_mailbox *
 920 _thr_sig_add(struct pthread *pthread, int sig, siginfo_t *info)
 921 {
 922         siginfo_t siginfo;
 923         struct kse *curkse;
 924         struct kse_mailbox *kmbx = NULL;
 925         struct pthread *curthread = _get_curthread();
 926         int     restart;
 927         int     suppress_handler = 0;
 928         int     fromproc = 0;
 929         __sighandler_t *sigfunc;
 930
 931         DBG_MSG(">>> _thr_sig_add %p (%d)\n", pthread, sig);
 932
 933         curkse = _get_curkse();
 934         restart = _thread_sigact[sig - 1].sa_flags & SA_RESTART;
 935         sigfunc = _thread_sigact[sig - 1].sa_handler;
 936         fromproc = (curthread == _thr_sig_daemon);
 937
 938         if (pthread->state == PS_DEAD || pthread->state == PS_DEADLOCK ||
 939             pthread->state == PS_STATE_MAX)
 940                 return (NULL); /* return false */
 941
 942         if ((pthread->attr.flags & PTHREAD_SCOPE_SYSTEM) &&
 943             (curthread != pthread)) {
 944                 PANIC("Please use _thr_send_sig for bound thread");
 945                 return (NULL);
 946         }
 947
 948         if (pthread->state != PS_SIGWAIT &&
 949             SIGISMEMBER(pthread->sigmask, sig)) {
 950                 /* signal is masked, just add signal to thread. */
 951                 if (!fromproc) {
 952                         SIGADDSET(pthread->sigpend, sig);
 953                         if (info == NULL)
 954                                 build_siginfo(&pthread->siginfo[sig-1], sig);
 955                         else if (info != &pthread->siginfo[sig-1])
 956                                 memcpy(&pthread->siginfo[sig-1], info,
 957                                          sizeof(*info));
 958                 } else {
 959                         if (!_thr_getprocsig(sig, &pthread->siginfo[sig-1]))
 960                                 return (NULL);
 961                         SIGADDSET(pthread->sigpend, sig);
 962                 }
 963         }
 964         else {
 965                 /* if process signal not exists, just return */
 966                 if (fromproc) {
 967                         if (!_thr_getprocsig(sig, &siginfo))
 968                                 return (NULL);
 969                         info = &siginfo;
 970                 }
 971
 972                 if (pthread->state != PS_SIGWAIT && sigfunc == SIG_DFL &&
 973                     (sigprop(sig) & SA_KILL)) {
 974                         kse_thr_interrupt(NULL, KSE_INTR_SIGEXIT, sig);
 975                         /* Never reach */
 976                 }
 977
 978                 /*
 979                  * Process according to thread state:
 980                  */
 981                 switch (pthread->state) {
 982                 case PS_DEAD:
 983                 case PS_DEADLOCK:
 984                 case PS_STATE_MAX:
 985                         return (NULL);  /* XXX return false */
 986                 case PS_LOCKWAIT:
 987                 case PS_SUSPENDED:
 988                         /*
 989                          * You can't call a signal handler for threads in these
 990                          * states.
 991                          */
 992                         suppress_handler = 1;
 993                         break;
 994                 case PS_RUNNING:
 995                         if ((pthread->flags & THR_FLAGS_IN_RUNQ)) {
 996                                 THR_RUNQ_REMOVE(pthread);
 997                                 pthread->active_priority |= THR_SIGNAL_PRIORITY;
 998                                 THR_RUNQ_INSERT_TAIL(pthread);
 999                         } else {
1000                                 /* Possible not in RUNQ and has curframe ? */
1001                                 pthread->active_priority |= THR_SIGNAL_PRIORITY;
1002                         }
1003                         break;
1004                 /*
1005                  * States which cannot be interrupted but still require the
1006                  * signal handler to run:
1007                  */
1008                 case PS_COND_WAIT:
1009                 case PS_MUTEX_WAIT:
1010                         break;
1011
1012                 case PS_SLEEP_WAIT:
1013                         /*
1014                          * Unmasked signals always cause sleep to terminate
1015                          * early regardless of SA_RESTART:
1016                          */
1017                         pthread->interrupted = 1;
1018                         break;
1019
1020                 case PS_JOIN:
1021                         break;
1022
1023                 case PS_SIGSUSPEND:
1024                         pthread->interrupted = 1;
1025                         break;
1026
1027                 case PS_SIGWAIT:
1028                         if (info == NULL)
1029                                 build_siginfo(&pthread->siginfo[sig-1], sig);
1030                         else if (info != &pthread->siginfo[sig-1])
1031                                 memcpy(&pthread->siginfo[sig-1], info,
1032                                         sizeof(*info));
1033                         /*
1034                          * The signal handler is not called for threads in
1035                          * SIGWAIT.
1036                          */
1037                         suppress_handler = 1;
1038                         /* Wake up the thread if the signal is not blocked. */
1039                         if (SIGISMEMBER(*(pthread->data.sigwait->waitset), sig)) {
1040                                 /* Return the signal number: */
1041                                 *(pthread->data.sigwait->siginfo) = pthread->siginfo[sig-1];
1042                                 /* Make the thread runnable: */
1043                                 kmbx = _thr_setrunnable_unlocked(pthread);
1044                         } else {
1045                                 /* Increment the pending signal count. */
1046                                 SIGADDSET(pthread->sigpend, sig);
1047                                 if (!SIGISMEMBER(pthread->sigmask, sig)) {
1048                                         if (sigfunc == SIG_DFL &&
1049                                             sigprop(sig) & SA_KILL) {
1050                                                 kse_thr_interrupt(NULL,
1051                                                          KSE_INTR_SIGEXIT,
1052                                                          sig);
1053                                                 /* Never reach */
1054                                         }
1055                                         pthread->check_pending = 1;
1056                                         pthread->interrupted = 1;
1057                                         kmbx = _thr_setrunnable_unlocked(pthread);
1058                                 }
1059                         }
1060                         return (kmbx);
1061                 }
1062
1063                 SIGADDSET(pthread->sigpend, sig);
1064                 if (info == NULL)
1065                         build_siginfo(&pthread->siginfo[sig-1], sig);
1066                 else if (info != &pthread->siginfo[sig-1])
1067                         memcpy(&pthread->siginfo[sig-1], info, sizeof(*info));
1068                 pthread->check_pending = 1;
1069                 if (!(pthread->attr.flags & PTHREAD_SCOPE_SYSTEM) &&
1070                     (pthread->blocked != 0) && !THR_IN_CRITICAL(pthread))
1071                         kse_thr_interrupt(&pthread->tcb->tcb_tmbx,
1072                             restart ? KSE_INTR_RESTART : KSE_INTR_INTERRUPT, 0);
1073                 if (suppress_handler == 0) {
1074                         /*
1075                          * Setup a signal frame and save the current threads
1076                          * state:
1077                          */
1078                         if (pthread->state != PS_RUNNING) {
1079                                 if (pthread->flags & THR_FLAGS_IN_RUNQ)
1080                                         THR_RUNQ_REMOVE(pthread);
1081                                 pthread->active_priority |= THR_SIGNAL_PRIORITY;
1082                                 kmbx = _thr_setrunnable_unlocked(pthread);
1083                         }
1084                 }
1085         }
1086         return (kmbx);
1087 }
1088
1089 /*
1090  * Send a signal to a specific thread (ala pthread_kill):
1091  */
1092 void
1093 _thr_sig_send(struct pthread *pthread, int sig)
1094 {
1095         struct pthread *curthread = _get_curthread();
1096         struct kse_mailbox *kmbx;
1097
1098         if (pthread->attr.flags & PTHREAD_SCOPE_SYSTEM) {
1099                 kse_thr_interrupt(&pthread->tcb->tcb_tmbx, KSE_INTR_SENDSIG, sig);
1100                 return;
1101         }
1102
1103         /* Lock the scheduling queue of the target thread. */
1104         THR_SCHED_LOCK(curthread, pthread);
1105         if (_thread_sigact[sig - 1].sa_handler != SIG_IGN) {
1106                 kmbx = _thr_sig_add(pthread, sig, NULL);
1107                 /* Add a preemption point. */
1108                 if (kmbx == NULL && (curthread->kseg == pthread->kseg) &&
1109                     (pthread->active_priority > curthread->active_priority))
1110                         curthread->critical_yield = 1;
1111                 THR_SCHED_UNLOCK(curthread, pthread);
1112                 if (kmbx != NULL)
1113                         kse_wakeup(kmbx);
1114                 /* XXX
1115                  * If thread sent signal to itself, check signals now.
1116                  * It is not really needed, _kse_critical_leave should
1117                  * have already checked signals.
1118                  */
1119                 if (pthread == curthread && curthread->check_pending)
1120                         _thr_sig_check_pending(curthread);
1121
1122         } else  {
1123                 THR_SCHED_UNLOCK(curthread, pthread);
1124         }
1125 }
1126
1127 static inline void
1128 thr_sigframe_restore(struct pthread *curthread, struct pthread_sigframe *psf)
1129 {
1130         kse_critical_t crit;
1131         struct kse *curkse;
1132
1133         THR_THREAD_LOCK(curthread, curthread);
1134         curthread->cancelflags = psf->psf_cancelflags;
1135         crit = _kse_critical_enter();
1136         curkse = curthread->kse;
1137         KSE_SCHED_LOCK(curkse, curthread->kseg);
1138         curthread->flags = psf->psf_flags;
1139         curthread->interrupted = psf->psf_interrupted;
1140         curthread->timeout = psf->psf_timeout;
1141         curthread->data = psf->psf_wait_data;
1142         curthread->wakeup_time = psf->psf_wakeup_time;
1143         curthread->continuation = psf->psf_continuation;
1144         KSE_SCHED_UNLOCK(curkse, curthread->kseg);
1145         _kse_critical_leave(crit);
1146         THR_THREAD_UNLOCK(curthread, curthread);
1147 }
1148
1149 static inline void
1150 thr_sigframe_save(struct pthread *curthread, struct pthread_sigframe *psf)
1151 {
1152         kse_critical_t crit;
1153         struct kse *curkse;
1154
1155         THR_THREAD_LOCK(curthread, curthread);
1156         psf->psf_cancelflags = curthread->cancelflags;
1157         crit = _kse_critical_enter();
1158         curkse = curthread->kse;
1159         KSE_SCHED_LOCK(curkse, curthread->kseg);
1160         /* This has to initialize all members of the sigframe. */
1161         psf->psf_flags = (curthread->flags & (THR_FLAGS_PRIVATE | THR_FLAGS_EXITING));
1162         psf->psf_interrupted = curthread->interrupted;
1163         psf->psf_timeout = curthread->timeout;
1164         psf->psf_wait_data = curthread->data;
1165         psf->psf_wakeup_time = curthread->wakeup_time;
1166         psf->psf_continuation = curthread->continuation;
1167         KSE_SCHED_UNLOCK(curkse, curthread->kseg);
1168         _kse_critical_leave(crit);
1169         THR_THREAD_UNLOCK(curthread, curthread);
1170 }
1171
1172 void
1173 _thr_signal_init(void)
1174 {
1175         struct sigaction act;
1176         __siginfohandler_t *sigfunc;
1177         int i;
1178         sigset_t sigset;
1179
1180         SIGFILLSET(sigset);
1181         __sys_sigprocmask(SIG_SETMASK, &sigset, &_thr_initial->sigmask);
1182         /* Enter a loop to get the existing signal status: */
1183         for (i = 1; i <= _SIG_MAXSIG; i++) {
1184                 /* Get the signal handler details: */
1185                 if (__sys_sigaction(i, NULL, &_thread_sigact[i - 1]) != 0) {
1186                         /*
1187                          * Abort this process if signal
1188                          * initialisation fails:
1189                          */
1190                         PANIC("Cannot read signal handler info");
1191                 }
1192                 /* Intall wrapper if handler was set */
1193                 sigfunc = _thread_sigact[i - 1].sa_sigaction;
1194                 if (((__sighandler_t *)sigfunc) != SIG_DFL &&
1195                     ((__sighandler_t *)sigfunc) != SIG_IGN) {
1196                         act = _thread_sigact[i - 1];
1197                         act.sa_flags |= SA_SIGINFO;
1198                         act.sa_sigaction =
1199                                 (__siginfohandler_t *)_thr_sig_handler;
1200                         __sys_sigaction(i, &act, NULL);
1201                 }
1202         }
1203         /*
1204          * Install the signal handler for SIGINFO.  It isn't
1205          * really needed, but it is nice to have for debugging
1206          * purposes.
1207          */
1208         _thread_sigact[SIGINFO - 1].sa_flags = SA_SIGINFO | SA_RESTART;
1209         SIGEMPTYSET(act.sa_mask);
1210         act.sa_flags = SA_SIGINFO | SA_RESTART;
1211         act.sa_sigaction = (__siginfohandler_t *)&_thr_sig_handler;
1212         if (__sys_sigaction(SIGINFO, &act, NULL) != 0) {
1213                 __sys_sigprocmask(SIG_SETMASK, &_thr_initial->sigmask, NULL);
1214                 /*
1215                  * Abort this process if signal initialisation fails:
1216                  */
1217                 PANIC("Cannot initialize signal handler");
1218         }
1219         __sys_sigprocmask(SIG_SETMASK, &_thr_initial->sigmask, NULL);
1220         __sys_sigaltstack(NULL, &_thr_initial->sigstk);
1221 }
1222
1223 void
1224 _thr_signal_deinit(void)
1225 {
1226         int i;
1227         struct pthread *curthread = _get_curthread();
1228
1229         /* Clear process pending signals. */
1230         sigemptyset(&_thr_proc_sigpending);
1231
1232         /* Enter a loop to get the existing signal status: */
1233         for (i = 1; i <= _SIG_MAXSIG; i++) {
1234                 /* Check for signals which cannot be trapped: */
1235                 if (i == SIGKILL || i == SIGSTOP) {
1236                 }
1237
1238                 /* Set the signal handler details: */
1239                 else if (__sys_sigaction(i, &_thread_sigact[i - 1],
1240                          NULL) != 0) {
1241                         /*
1242                          * Abort this process if signal
1243                          * initialisation fails:
1244                          */
1245                         PANIC("Cannot set signal handler info");
1246                 }
1247         }
1248         __sys_sigaltstack(&curthread->sigstk, NULL);
1249 }
1250