linuxthreads/sighandler.c

   1 /* Linuxthreads - a simple clone()-based implementation of Posix        */
   2 /* threads for Linux.                                                   */
   3 /* Copyright (C) 1996 Xavier Leroy (Xavier.Leroy@inria.fr)              */
   4 /*                                                                      */
   5 /* This program is free software; you can redistribute it and/or        */
   6 /* modify it under the terms of the GNU Library General Public License  */
   7 /* as published by the Free Software Foundation; either version 2       */
   8 /* of the License, or (at your option) any later version.               */
   9 /*                                                                      */
  10 /* This program is distributed in the hope that it will be useful,      */
  11 /* but WITHOUT ANY WARRANTY; without even the implied warranty of       */
  12 /* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the        */
  13 /* GNU Library General Public License for more details.                 */
  14
  15 /* Signal handlers */
  16
  17 #include "internals.h"
  18
  19
  20 /* The wrapper around user-provided signal handlers */
  21 void __pthread_sighandler(int signo, SIGCONTEXT ctx)
  22 {
  23   pthread_descr self;
  24   char * in_sighandler;
  25   self = thread_self();
  26   /* If we're in a sigwait operation, just record the signal received
  27      and return without calling the user's handler */
  28   if (THREAD_GETMEM(self, p_sigwaiting)) {
  29     THREAD_SETMEM(self, p_sigwaiting, 0);
  30     THREAD_SETMEM(self, p_signal, signo);
  31     return;
  32   }
  33   /* Record that we're in a signal handler and call the user's
  34      handler function */
  35   in_sighandler = THREAD_GETMEM(self, p_in_sighandler);
  36   if (in_sighandler == NULL)
  37     THREAD_SETMEM(self, p_in_sighandler, CURRENT_STACK_FRAME);
  38   CALL_SIGHANDLER(__sighandler[signo].old, signo, ctx);
  39   if (in_sighandler == NULL)
  40     THREAD_SETMEM(self, p_in_sighandler, NULL);
  41 }
  42
  43 /* The same, this time for real-time signals.  */
  44 void __pthread_sighandler_rt(int signo, struct siginfo *si,
  45                              struct ucontext *uc)
  46 {
  47   pthread_descr self;
  48   char * in_sighandler;
  49   self =  thread_self();
  50   /* If we're in a sigwait operation, just record the signal received
  51      and return without calling the user's handler */
  52   if (THREAD_GETMEM(self, p_sigwaiting)) {
  53     THREAD_SETMEM(self, p_sigwaiting, 0);
  54     THREAD_SETMEM(self, p_signal, signo);
  55     return;
  56   }
  57   /* Record that we're in a signal handler and call the user's
  58      handler function */
  59   in_sighandler = THREAD_GETMEM(self, p_in_sighandler);
  60   if (in_sighandler == NULL)
  61     THREAD_SETMEM(self, p_in_sighandler, CURRENT_STACK_FRAME);
  62   __sighandler[signo].rt(signo, si, uc);
  63   if (in_sighandler == NULL)
  64     THREAD_SETMEM(self, p_in_sighandler, NULL);
  65 }
  66
  67
  68 /* A signal handler that does nothing */
  69 void __pthread_null_sighandler(int sig) { }