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 = check_thread_self();
  26
  27   /* If we're in a sigwait operation, just record the signal received
  28      and return without calling the user's handler */
  29   if (THREAD_GETMEM(self, p_sigwaiting)) {
  30     THREAD_SETMEM(self, p_sigwaiting, 0);
  31     THREAD_SETMEM(self, p_signal, signo);
  32     return;
  33   }
  34   /* Record that we're in a signal handler and call the user's
  35      handler function */
  36   in_sighandler = THREAD_GETMEM(self, p_in_sighandler);
  37   if (in_sighandler == NULL)
  38     THREAD_SETMEM(self, p_in_sighandler, CURRENT_STACK_FRAME);
  39   CALL_SIGHANDLER(__sighandler[signo].old, signo, ctx);
  40   if (in_sighandler == NULL)
  41     THREAD_SETMEM(self, p_in_sighandler, NULL);
  42 }
  43
  44 /* The same, this time for real-time signals.  */
  45 void __pthread_sighandler_rt(int signo, struct siginfo *si,
  46                              struct ucontext *uc)
  47 {
  48   pthread_descr self;
  49   char * in_sighandler;
  50   self = check_thread_self();
  51
  52   /* If we're in a sigwait operation, just record the signal received
  53      and return without calling the user's handler */
  54   if (THREAD_GETMEM(self, p_sigwaiting)) {
  55     THREAD_SETMEM(self, p_sigwaiting, 0);
  56     THREAD_SETMEM(self, p_signal, signo);
  57     return;
  58   }
  59   /* Record that we're in a signal handler and call the user's
  60      handler function */
  61   in_sighandler = THREAD_GETMEM(self, p_in_sighandler);
  62   if (in_sighandler == NULL)
  63     THREAD_SETMEM(self, p_in_sighandler, CURRENT_STACK_FRAME);
  64   __sighandler[signo].rt(signo, si, uc);
  65   if (in_sighandler == NULL)
  66     THREAD_SETMEM(self, p_in_sighandler, NULL);
  67 }
  68
  69
  70 /* A signal handler that does nothing */
  71 void __pthread_null_sighandler(int sig) { }