lib/binary-io.h

   1 /* Binary mode I/O.
   2    Copyright (C) 2001, 2003, 2005, 2008-2024 Free Software Foundation, Inc.
   3
   4    This file is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU Lesser General Public License as
   6    published by the Free Software Foundation; either version 2.1 of the
   7    License, or (at your option) any later version.
   8
   9    This file is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public License
  15    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  16
  17 #ifndef _BINARY_H
  18 #define _BINARY_H
  19
  20 /* This file uses _GL_INLINE_HEADER_BEGIN, _GL_INLINE, _GL_UNUSED.  */
  21 #if !_GL_CONFIG_H_INCLUDED
  22  #error "Please include config.h first."
  23 #endif
  24
  25 /* For systems that distinguish between text and binary I/O.
  26    O_BINARY is guaranteed by the gnulib <fcntl.h>. */
  27 #include <fcntl.h>
  28
  29 /* The MSVC7 <stdio.h> doesn't like to be included after '#define fileno ...',
  30    so we include it here first.  */
  31 #include <stdio.h>
  32
  33 _GL_INLINE_HEADER_BEGIN
  34 #ifndef BINARY_IO_INLINE
  35 # define BINARY_IO_INLINE _GL_INLINE
  36 #endif
  37
  38 #if O_BINARY
  39 # if defined __EMX__ || defined __DJGPP__ || defined __CYGWIN__
  40 #  include <io.h> /* declares setmode() */
  41 #  define __gl_setmode setmode
  42 # else
  43 #  define __gl_setmode _setmode
  44 #  undef fileno
  45 #  define fileno _fileno
  46 # endif
  47 #else
  48   /* On reasonable systems, binary I/O is the only choice.  */
  49   /* Use a function rather than a macro, to avoid gcc warnings
  50      "warning: statement with no effect".  */
  51 BINARY_IO_INLINE int
  52 __gl_setmode (_GL_UNUSED int fd, _GL_UNUSED int mode)
  53 {
  54   return O_BINARY;
  55 }
  56 #endif
  57
  58 #ifdef __cplusplus
  59 extern "C" {
  60 #endif
  61
  62
  63 /* Set FD's mode to MODE, which should be either O_TEXT or O_BINARY.
  64    Return the old mode if successful, -1 (setting errno) on failure.
  65    Ordinarily this function would be called 'setmode', since that is
  66    its old name on MS-Windows, but it is called 'set_binary_mode' here
  67    to avoid colliding with a BSD function of another name.  */
  68
  69 #if defined __DJGPP__ || defined __EMX__
  70 extern int set_binary_mode (int fd, int mode);
  71 #else
  72 BINARY_IO_INLINE int
  73 set_binary_mode (int fd, int mode)
  74 {
  75   return __gl_setmode (fd, mode);
  76 }
  77 #endif
  78
  79 /* This macro is obsolescent.  */
  80 #define SET_BINARY(fd) ((void) set_binary_mode (fd, O_BINARY))
  81
  82
  83 #ifdef __cplusplus
  84 }
  85 #endif
  86
  87 _GL_INLINE_HEADER_END
  88
  89 #endif /* _BINARY_H */