sysdeps/generic/sigset.h

   1 /* __sig_atomic_t, __sigset_t, and related definitions.  Generic/BSD version.
   2 Copyright (C) 1991, 1992, 1994, 1996 Free Software Foundation, Inc.
   3 This file is part of the GNU C Library.
   4
   5 The GNU C Library is free software; you can redistribute it and/or
   6 modify it under the terms of the GNU Library General Public License as
   7 published by the Free Software Foundation; either version 2 of the
   8 License, or (at your option) any later version.
   9
  10 The GNU C Library 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 GNU
  13 Library General Public License for more details.
  14
  15 You should have received a copy of the GNU Library General Public
  16 License along with the GNU C Library; see the file COPYING.LIB.  If
  17 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
  18 Cambridge, MA 02139, USA.  */
  19
  20 #ifndef _SIGSET_H_types
  21 #define _SIGSET_H_types 1
  22
  23 typedef int __sig_atomic_t;
  24
  25 /* A `sigset_t' has a bit for each signal.  */
  26 typedef unsigned long int __sigset_t;
  27
  28 #endif
  29
  30
  31 /* We only want to define these functions if <signal.h> was actually
  32    included; otherwise we were included just to define the types.  Since we
  33    are namespace-clean, it wouldn't hurt to define extra macros.  But
  34    trouble can be caused by functions being defined (e.g., any global
  35    register vars declared later will cause compilation errors).  */
  36
  37 #if !defined (_SIGSET_H_fns) && defined (_SIGNAL_H)
  38 #define _SIGSET_H_fns 1
  39
  40 /* Return a mask that includes SIG only.  The cast to `sigset_t' avoids
  41    overflow if `sigset_t' is wider than `int'.  */
  42 #define __sigmask(sig)  (((__sigset_t) 1) << ((sig) - 1))
  43
  44 #define __sigemptyset(set)      ((*(set) = (__sigset_t) 0), 0)
  45 #define __sigfillset(set)       ((*(set) = ~(__sigset_t) 0), 0)
  46
  47 /* These functions must check for a bogus signal number.  We detect it by a
  48    zero sigmask, since a number too low or too high will have shifted the 1
  49    off the high end of the mask.  If we find an error, we punt to a random
  50    call we know fails with EINVAL (kludge city!), so as to avoid referring
  51    to `errno' in this file (sigh).  */
  52
  53 extern int __sigismember (__const __sigset_t *, int);
  54 extern int __sigaddset (__sigset_t *, int);
  55 extern int __sigdelset (__sigset_t *, int);
  56
  57 #ifndef _EXTERN_INLINE
  58 #define _EXTERN_INLINE extern __inline
  59 #endif
  60 #define __SIGSETFN(NAME, BODY, CONST)                                         \
  61   _EXTERN_INLINE int                                                          \
  62   __##NAME (CONST __sigset_t *__set, int __sig)                               \
  63   {                                                                           \
  64     if (__sig < 1 || __sig > (int) sizeof (__sigset_t) * 8)                   \
  65       {                                                                       \
  66         extern int raise (int);                                               \
  67         return raise (-1);                                                    \
  68       }                                                                       \
  69     else                                                                      \
  70       {                                                                       \
  71         __sigset_t __mask = __sigmask (__sig);                                \
  72         return BODY;                                                          \
  73       }                                                                       \
  74   }
  75
  76 __SIGSETFN (sigismember, (*__set & __mask) ? 1 : 0, __const)
  77 __SIGSETFN (sigaddset, ((*__set |= __mask), 0), )
  78 __SIGSETFN (sigdelset, ((*__set &= ~__mask), 0), )
  79
  80 #undef __SIGSETFN
  81
  82
  83 #endif /* ! _SIGSET_H_fns.  */