1  /* Copyright (C) 1997-2023 Free Software Foundation, Inc.
       2     This file is part of the GNU C Library.
       3  
       4     The GNU C Library is free software; you can redistribute it and/or
       5     modify it under the terms of the GNU Lesser General Public
       6     License as published by the Free Software Foundation; either
       7     version 2.1 of the License, or (at your option) any later version.
       8  
       9     The GNU C Library is distributed in the hope that it will be useful,
      10     but WITHOUT ANY WARRANTY; without even the implied warranty of
      11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      12     Lesser General Public License for more details.
      13  
      14     You should have received a copy of the GNU Lesser General Public
      15     License along with the GNU C Library; if not, see
      16     <https://www.gnu.org/licenses/>.  */
      17  
      18  #include <errno.h>
      19  #include <signal.h>
      20  #include <string.h>
      21  
      22  #include <sysdep.h>
      23  #include <sys/syscall.h>
      24  
      25  /* New ports should not define the obsolete SA_RESTORER, however some
      26     architecture requires for compat mode and/or due old ABI.  */
      27  #include <kernel_sigaction.h>
      28  
      29  #ifndef SA_RESTORER
      30  # define SET_SA_RESTORER(kact, act)
      31  # define RESET_SA_RESTORER(act, kact)
      32  #endif
      33  
      34  /* SPARC passes the restore function as an argument to rt_sigaction.  */
      35  #ifndef STUB
      36  # define STUB(act, sigsetsize) (sigsetsize)
      37  #endif
      38  
      39  /* If ACT is not NULL, change the action for SIG to *ACT.
      40     If OACT is not NULL, put the old action for SIG in *OACT.  */
      41  int
      42  __libc_sigaction (int sig, const struct sigaction *act, struct sigaction *oact)
      43  {
      44    int result;
      45  
      46    struct kernel_sigaction kact, koact;
      47  
      48    if (act)
      49      {
      50        kact.k_sa_handler = act->sa_handler;
      51        memcpy (&kact.sa_mask, &act->sa_mask, sizeof (sigset_t));
      52        kact.sa_flags = act->sa_flags;
      53        SET_SA_RESTORER (&kact, act);
      54      }
      55  
      56    /* XXX The size argument hopefully will have to be changed to the
      57       real size of the user-level sigset_t.  */
      58    result = INLINE_SYSCALL_CALL (rt_sigaction, sig,
      59  				act ? &kact : NULL,
      60  				oact ? &koact : NULL, STUB (act,
      61  							    __NSIG_BYTES));
      62  
      63    if (oact && result >= 0)
      64      {
      65        oact->sa_handler = koact.k_sa_handler;
      66        memcpy (&oact->sa_mask, &koact.sa_mask, sizeof (sigset_t));
      67        oact->sa_flags = koact.sa_flags;
      68        RESET_SA_RESTORER (oact, &koact);
      69      }
      70    return result;
      71  }
      72  libc_hidden_def (__libc_sigaction)