src/sysselect.h

   1 /* sysselect.h - System-dependent definitions for the select function.
   2    Copyright (C) 1995, 2001-2013 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
   9 (at 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 <http://www.gnu.org/licenses/>.  */
  18
  19 #ifndef EMACS_SYSSELECT_H
  20 #define EMACS_SYSSELECT_H
  21
  22 #ifndef DOS_NT
  23 #include <sys/select.h>
  24 #endif
  25
  26 #ifdef WINDOWSNT
  27
  28 /* File descriptor set emulation.  */
  29
  30 /* MSVC runtime library has limit of 64 descriptors by default */
  31 #define FD_SETSIZE  64
  32 typedef struct {
  33   unsigned int bits[FD_SETSIZE / 32];
  34 } fd_set;
  35
  36 /* standard access macros */
  37 #define FD_SET(n, p) \
  38   do { \
  39     if ((n) < FD_SETSIZE) { \
  40       (p)->bits[(n)/32] |= (1 << (n)%32); \
  41     } \
  42   } while (0)
  43 #define FD_CLR(n, p) \
  44   do { \
  45     if ((n) < FD_SETSIZE) { \
  46       (p)->bits[(n)/32] &= ~(1 << (n)%32); \
  47     } \
  48   } while (0)
  49 #define FD_ISSET(n, p) ((n) < FD_SETSIZE ? ((p)->bits[(n)/32] & (1 << (n)%32)) : 0)
  50 #define FD_ZERO(p) memset((p), 0, sizeof(fd_set))
  51
  52 #define SELECT_TYPE fd_set
  53
  54 #include "systime.h"
  55 extern int sys_select (int, SELECT_TYPE *, SELECT_TYPE *, SELECT_TYPE *,
  56                        EMACS_TIME *, sigset_t *);
  57
  58 #else  /* not WINDOWSNT */
  59
  60 #ifdef FD_SET
  61 #ifdef FD_SETSIZE
  62 #define MAXDESC FD_SETSIZE
  63 #else
  64 #define MAXDESC 64
  65 #endif
  66 #define SELECT_TYPE fd_set
  67 #else /* no FD_SET */
  68 #define MAXDESC 32
  69 #define SELECT_TYPE int
  70
  71 /* Define the macros to access a single-int bitmap of descriptors.  */
  72 #define FD_SET(n, p) (*(p) |= (1 << (n)))
  73 #define FD_CLR(n, p) (*(p) &= ~(1 << (n)))
  74 #define FD_ISSET(n, p) (*(p) & (1 << (n)))
  75 #define FD_ZERO(p) (*(p) = 0)
  76 #endif /* no FD_SET */
  77 #endif /* not WINDOWSNT */
  78
  79 #if !defined (HAVE_SELECT)
  80 #define select sys_select
  81 #endif
  82
  83 #ifdef MSDOS
  84 #define pselect sys_select
  85 #endif
  86
  87 #endif  /* EMACS_SYSSELECT_H */