ffap: Don't switch window unless needed
[emacs.git] / src / sysselect.h
blob2ddea665b308aef687041beaad8385a972b953e4
1 /* sysselect.h - System-dependent definitions for the select function.
2 Copyright (C) 1995, 2001-2017 Free Software Foundation, Inc.
4 This file is part of GNU Emacs.
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.
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.
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/>. */
19 #ifndef SYSSELECT_H
20 #define SYSSELECT_H 1
22 #ifndef DOS_NT
23 #include <sys/select.h>
24 #endif
26 #include "lisp.h"
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;
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 */
48 #if !defined (HAVE_SELECT)
49 #define select sys_select
50 #endif
52 #ifdef MSDOS
53 #define pselect sys_select
54 #endif
56 #ifndef WINDOWSNT
57 INLINE_HEADER_BEGIN
59 /* Check for out-of-range errors if ENABLE_CHECKING is defined. */
61 INLINE void
62 fd_CLR (int fd, fd_set *set)
64 eassume (0 <= fd && fd < FD_SETSIZE);
65 FD_CLR (fd, set);
68 INLINE bool
69 fd_ISSET (int fd, fd_set *set)
71 eassume (0 <= fd && fd < FD_SETSIZE);
72 return FD_ISSET (fd, set) != 0;
75 INLINE void
76 fd_SET (int fd, fd_set *set)
78 eassume (0 <= fd && fd < FD_SETSIZE);
79 FD_SET (fd, set);
82 #undef FD_CLR
83 #undef FD_ISSET
84 #undef FD_SET
85 #define FD_CLR(fd, set) fd_CLR (fd, set)
86 #define FD_ISSET(fd, set) fd_ISSET (fd, set)
87 #define FD_SET(fd, set) fd_SET (fd, set)
89 INLINE_HEADER_END
91 #endif /* !WINDOWSNT */
93 #endif