emacs/lib/binary-io.h

90 lines
2.5 KiB
C

/* Binary mode I/O.
Copyright (C) 2001, 2003, 2005, 2008-2024 Free Software Foundation, Inc.
This file is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as
published by the Free Software Foundation; either version 2.1 of the
License, or (at your option) any later version.
This file is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>. */
#ifndef _BINARY_H
#define _BINARY_H
/* This file uses _GL_INLINE_HEADER_BEGIN, _GL_INLINE, _GL_UNUSED. */
#if !_GL_CONFIG_H_INCLUDED
#error "Please include config.h first."
#endif
/* For systems that distinguish between text and binary I/O.
O_BINARY is guaranteed by the gnulib <fcntl.h>. */
#include <fcntl.h>
/* The MSVC7 <stdio.h> doesn't like to be included after '#define fileno ...',
so we include it here first. */
#include <stdio.h>
_GL_INLINE_HEADER_BEGIN
#ifndef BINARY_IO_INLINE
# define BINARY_IO_INLINE _GL_INLINE
#endif
#if O_BINARY
# if defined __EMX__ || defined __DJGPP__ || defined __CYGWIN__
# include <io.h> /* declares setmode() */
# define __gl_setmode setmode
# else
# define __gl_setmode _setmode
# undef fileno
# define fileno _fileno
# endif
#else
/* On reasonable systems, binary I/O is the only choice. */
/* Use a function rather than a macro, to avoid gcc warnings
"warning: statement with no effect". */
BINARY_IO_INLINE int
__gl_setmode (_GL_UNUSED int fd, _GL_UNUSED int mode)
{
return O_BINARY;
}
#endif
#ifdef __cplusplus
extern "C" {
#endif
/* Set FD's mode to MODE, which should be either O_TEXT or O_BINARY.
Return the old mode if successful, -1 (setting errno) on failure.
Ordinarily this function would be called 'setmode', since that is
its old name on MS-Windows, but it is called 'set_binary_mode' here
to avoid colliding with a BSD function of another name. */
#if defined __DJGPP__ || defined __EMX__
extern int set_binary_mode (int fd, int mode);
#else
BINARY_IO_INLINE int
set_binary_mode (int fd, int mode)
{
return __gl_setmode (fd, mode);
}
#endif
/* This macro is obsolescent. */
#define SET_BINARY(fd) ((void) set_binary_mode (fd, O_BINARY))
#ifdef __cplusplus
}
#endif
_GL_INLINE_HEADER_END
#endif /* _BINARY_H */