src/sysselect.h

   1 /* sysselect.h - System-dependent definitions for the select function.
   2    Copyright (C) 1995, 2001-2018 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Emacs.
   5
   6 GNU Emacs is free software: you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation, either version 3 of the License, or (at
   9 your option) any later version.
  10
  11 GNU Emacs is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */
  18
  19 #ifndef SYSSELECT_H
  20 #define SYSSELECT_H 1
  21
  22 #ifndef DOS_NT
  23 #include <sys/select.h>
  24 #endif
  25
  26 #include "lisp.h"
  27
  28 /* The w32 build defines select stuff in w32.h, which is included
  29    where w32 needs it, but not where sysselect.h is included.  The w32
  30    definitions in w32.h are incompatible with the below.  */
  31 #ifndef WINDOWSNT
  32 #ifdef FD_SET
  33 #ifndef FD_SETSIZE
  34 #define FD_SETSIZE 64
  35 #endif
  36 #else /* no FD_SET */
  37 #define FD_SETSIZE 32
  38 typedef int fd_set;
  39
  40 /* Define the macros to access a single-int bitmap of descriptors.  */
  41 #define FD_SET(n, p) (*(p) |= (1 << (n)))
  42 #define FD_CLR(n, p) (*(p) &= ~(1 << (n)))
  43 #define FD_ISSET(n, p) (*(p) & (1 << (n)))
  44 #define FD_ZERO(p) (*(p) = 0)
  45 #endif /* no FD_SET */
  46 #endif /* not WINDOWSNT */
  47
  48 #if !defined (HAVE_SELECT)
  49 #define select sys_select
  50 #endif
  51
  52 #ifdef MSDOS
  53 /* The above #define for 'select' gets in the way because sysselect.h
  54    is included in thread.h, which is included everywhere, and 'select'
  55    declared in DJGPP system headers has a signature incompatible with
  56    'pselect', which we emulate in msdos.c.  */
  57 #undef select
  58 #define pselect sys_select
  59 #endif
  60
  61 #ifndef WINDOWSNT
  62 INLINE_HEADER_BEGIN
  63
  64 /* Check for out-of-range errors if ENABLE_CHECKING is defined.  */
  65
  66 INLINE void
  67 fd_CLR (int fd, fd_set *set)
  68 {
  69   eassume (0 <= fd && fd < FD_SETSIZE);
  70   FD_CLR (fd, set);
  71 }
  72
  73 INLINE bool
  74 fd_ISSET (int fd, fd_set *set)
  75 {
  76   eassume (0 <= fd && fd < FD_SETSIZE);
  77   return FD_ISSET (fd, set) != 0;
  78 }
  79
  80 INLINE void
  81 fd_SET (int fd, fd_set *set)
  82 {
  83   eassume (0 <= fd && fd < FD_SETSIZE);
  84   FD_SET (fd, set);
  85 }
  86
  87 #undef FD_CLR
  88 #undef FD_ISSET
  89 #undef FD_SET
  90 #define FD_CLR(fd, set) fd_CLR (fd, set)
  91 #define FD_ISSET(fd, set) fd_ISSET (fd, set)
  92 #define FD_SET(fd, set) fd_SET (fd, set)
  93
  94 INLINE_HEADER_END
  95
  96 #endif  /* !WINDOWSNT */
  97
  98 #endif