sysdeps/unix/sysv/linux/bits/sigset.h

   1 /* __sig_atomic_t, __sigset_t, and related definitions.  Linux version.
   2    Copyright (C) 1991-2014 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 Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the 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    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #ifndef _SIGSET_H_types
  20 # define _SIGSET_H_types        1
  21
  22 typedef int __sig_atomic_t;
  23
  24 /* A `sigset_t' has a bit for each signal.  */
  25
  26 # define _SIGSET_NWORDS (1024 / (8 * sizeof (unsigned long int)))
  27 typedef struct
  28   {
  29     unsigned long int __val[_SIGSET_NWORDS];
  30   } __sigset_t;
  31
  32 #endif
  33
  34
  35 /* We only want to define these functions if <signal.h> was actually
  36    included; otherwise we were included just to define the types.  Since we
  37    are namespace-clean, it wouldn't hurt to define extra macros.  But
  38    trouble can be caused by functions being defined (e.g., any global
  39    register vars declared later will cause compilation errors).  */
  40
  41 #if !defined _SIGSET_H_fns && defined _SIGNAL_H
  42 # define _SIGSET_H_fns 1
  43
  44 # ifndef _EXTERN_INLINE
  45 #  define _EXTERN_INLINE __extern_inline
  46 # endif
  47
  48 /* Return a mask that includes the bit for SIG only.  */
  49 # define __sigmask(sig) \
  50   (((unsigned long int) 1) << (((sig) - 1) % (8 * sizeof (unsigned long int))))
  51
  52 /* Return the word index for SIG.  */
  53 # define __sigword(sig) (((sig) - 1) / (8 * sizeof (unsigned long int)))
  54
  55 # if defined __GNUC__ && __GNUC__ >= 2
  56 #  define __sigemptyset(set) \
  57   (__extension__ ({ int __cnt = _SIGSET_NWORDS;                               \
  58                     sigset_t *__set = (set);                                  \
  59                     while (--__cnt >= 0) __set->__val[__cnt] = 0;             \
  60                     0; }))
  61 #  define __sigfillset(set) \
  62   (__extension__ ({ int __cnt = _SIGSET_NWORDS;                               \
  63                     sigset_t *__set = (set);                                  \
  64                     while (--__cnt >= 0) __set->__val[__cnt] = ~0UL;          \
  65                     0; }))
  66
  67 #  ifdef __USE_GNU
  68 /* The POSIX does not specify for handling the whole signal set in one
  69    command.  This is often wanted and so we define three more functions
  70    here.  */
  71 #   define __sigisemptyset(set) \
  72   (__extension__ ({ int __cnt = _SIGSET_NWORDS;                               \
  73                     const sigset_t *__set = (set);                            \
  74                     int __ret = __set->__val[--__cnt];                        \
  75                     while (!__ret && --__cnt >= 0)                            \
  76                         __ret = __set->__val[__cnt];                          \
  77                     __ret == 0; }))
  78 #   define __sigandset(dest, left, right) \
  79   (__extension__ ({ int __cnt = _SIGSET_NWORDS;                               \
  80                     sigset_t *__dest = (dest);                                \
  81                     const sigset_t *__left = (left);                          \
  82                     const sigset_t *__right = (right);                        \
  83                     while (--__cnt >= 0)                                      \
  84                       __dest->__val[__cnt] = (__left->__val[__cnt]            \
  85                                               & __right->__val[__cnt]);       \
  86                     0; }))
  87 #   define __sigorset(dest, left, right) \
  88   (__extension__ ({ int __cnt = _SIGSET_NWORDS;                               \
  89                     sigset_t *__dest = (dest);                                \
  90                     const sigset_t *__left = (left);                          \
  91                     const sigset_t *__right = (right);                        \
  92                     while (--__cnt >= 0)                                      \
  93                       __dest->__val[__cnt] = (__left->__val[__cnt]            \
  94                                               | __right->__val[__cnt]);       \
  95                     0; }))
  96 #  endif
  97 # endif
  98
  99 /* These functions needn't check for a bogus signal number -- error
 100    checking is done in the non __ versions.  */
 101
 102 extern int __sigismember (const __sigset_t *, int);
 103 extern int __sigaddset (__sigset_t *, int);
 104 extern int __sigdelset (__sigset_t *, int);
 105
 106 # ifdef __USE_EXTERN_INLINES
 107 #  define __SIGSETFN(NAME, BODY, CONST)                                       \
 108   _EXTERN_INLINE int                                                          \
 109   NAME (CONST __sigset_t *__set, int __sig)                                   \
 110   {                                                                           \
 111     unsigned long int __mask = __sigmask (__sig);                             \
 112     unsigned long int __word = __sigword (__sig);                             \
 113     return BODY;                                                              \
 114   }
 115
 116 __SIGSETFN (__sigismember, (__set->__val[__word] & __mask) ? 1 : 0, const)
 117 __SIGSETFN (__sigaddset, ((__set->__val[__word] |= __mask), 0), )
 118 __SIGSETFN (__sigdelset, ((__set->__val[__word] &= ~__mask), 0), )
 119
 120 #  undef __SIGSETFN
 121 # endif
 122
 123
 124 #endif /* ! _SIGSET_H_fns.  */