sig.h

   1 /* sig.h -- header file for signal handler definitions. */
   2
   3 /* Copyright (C) 1994-2013 Free Software Foundation, Inc.
   4
   5    This file is part of GNU Bash, the Bourne Again SHell.
   6
   7    Bash is free software: you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation, either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    Bash is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with Bash.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 /* Make sure that this is included *after* config.h! */
  22
  23 #if !defined (_SIG_H_)
  24 #  define _SIG_H_
  25
  26 #include "stdc.h"
  27
  28 #include <signal.h>             /* for sig_atomic_t */
  29
  30 #if !defined (SIGABRT) && defined (SIGIOT)
  31 #  define SIGABRT SIGIOT
  32 #endif
  33
  34 #define sighandler void
  35 typedef void SigHandler PARAMS((int));
  36
  37 #define SIGRETURN(n)    return
  38
  39 /* Here is a definition for set_signal_handler () which simply expands to
  40    a call to signal () for non-Posix systems.  The code for set_signal_handler
  41    in the Posix case resides in general.c. */
  42 #if !defined (HAVE_POSIX_SIGNALS)
  43 #  define set_signal_handler(sig, handler) (SigHandler *)signal (sig, handler)
  44 #else
  45 extern SigHandler *set_signal_handler PARAMS((int, SigHandler *));      /* in sig.c */
  46 #endif /* _POSIX_VERSION */
  47
  48 #if !defined (SIGCHLD) && defined (SIGCLD)
  49 #  define SIGCHLD SIGCLD
  50 #endif
  51
  52 #if !defined (HAVE_POSIX_SIGNALS) && !defined (sigmask)
  53 #  define sigmask(x) (1 << ((x)-1))
  54 #endif /* !HAVE_POSIX_SIGNALS && !sigmask */
  55
  56 #if !defined (HAVE_POSIX_SIGNALS)
  57 #  if !defined (SIG_BLOCK)
  58 #    define SIG_BLOCK 2
  59 #    define SIG_SETMASK 3
  60 #  endif /* SIG_BLOCK */
  61
  62 /* sigset_t defined in config.h */
  63
  64 /* Make sure there is nothing inside the signal set. */
  65 #  define sigemptyset(set) (*(set) = 0)
  66
  67 /* Initialize the signal set to hold all signals. */
  68 #  define sigfillset(set) (*set) = sigmask (NSIG) - 1
  69
  70 /* Add SIG to the contents of SET. */
  71 #  define sigaddset(set, sig) *(set) |= sigmask (sig)
  72
  73 /* Delete SIG from signal set SET. */
  74 #  define sigdelset(set, sig) *(set) &= ~sigmask (sig)
  75
  76 /* Is SIG a member of the signal set SET? */
  77 #  define sigismember(set, sig) ((*(set) & sigmask (sig)) != 0)
  78
  79 /* Suspend the process until the reception of one of the signals
  80    not present in SET. */
  81 #  define sigsuspend(set) sigpause (*(set))
  82 #endif /* !HAVE_POSIX_SIGNALS */
  83
  84 /* These definitions are used both in POSIX and non-POSIX implementations. */
  85
  86 #define BLOCK_SIGNAL(sig, nvar, ovar) \
  87 do { \
  88   sigemptyset (&nvar); \
  89   sigaddset (&nvar, sig); \
  90   sigemptyset (&ovar); \
  91   sigprocmask (SIG_BLOCK, &nvar, &ovar); \
  92 } while (0)
  93
  94 #define UNBLOCK_SIGNAL(ovar) sigprocmask (SIG_SETMASK, &ovar, (sigset_t *) NULL)
  95
  96 #if defined (HAVE_POSIX_SIGNALS)
  97 #  define BLOCK_CHILD(nvar, ovar) BLOCK_SIGNAL (SIGCHLD, nvar, ovar)
  98 #  define UNBLOCK_CHILD(ovar) UNBLOCK_SIGNAL(ovar)
  99 #else /* !HAVE_POSIX_SIGNALS */
 100 #  define BLOCK_CHILD(nvar, ovar) ovar = sigblock (sigmask (SIGCHLD))
 101 #  define UNBLOCK_CHILD(ovar) sigsetmask (ovar)
 102 #endif /* !HAVE_POSIX_SIGNALS */
 103
 104 /* Extern variables */
 105 extern volatile sig_atomic_t sigwinch_received;
 106 extern volatile sig_atomic_t sigterm_received;
 107
 108 extern int interrupt_immediately;       /* no longer used */
 109 extern int terminate_immediately;
 110
 111 /* Functions from sig.c. */
 112 extern sighandler termsig_sighandler PARAMS((int));
 113 extern void termsig_handler PARAMS((int));
 114 extern sighandler sigint_sighandler PARAMS((int));
 115 extern void initialize_signals PARAMS((int));
 116 extern void initialize_terminating_signals PARAMS((void));
 117 extern void reset_terminating_signals PARAMS((void));
 118 extern void top_level_cleanup PARAMS((void));
 119 extern void throw_to_top_level PARAMS((void));
 120 extern void jump_to_top_level PARAMS((int)) __attribute__((__noreturn__));
 121 extern void restore_sigmask PARAMS((void));
 122
 123 extern sighandler sigwinch_sighandler PARAMS((int));
 124 extern void set_sigwinch_handler PARAMS((void));
 125 extern void unset_sigwinch_handler PARAMS((void));
 126
 127 extern sighandler sigterm_sighandler PARAMS((int));
 128
 129 /* Functions defined in trap.c. */
 130 extern SigHandler *set_sigint_handler PARAMS((void));
 131 extern SigHandler *trap_to_sighandler PARAMS((int));
 132 extern sighandler trap_handler PARAMS((int));
 133
 134 extern int block_trapped_signals PARAMS((sigset_t *, sigset_t *));
 135 extern int unblock_trapped_signals PARAMS((sigset_t *));
 136 #endif /* _SIG_H_ */