libiberty/fopen_unlocked.c

   1 /* Implement fopen_unlocked and related functions.
   2    Copyright (C) 2005 Free Software Foundation, Inc.
   3    Written by Kaveh R. Ghazi <ghazi@caip.rutgers.edu>.
   4
   5 This file is part of the libiberty library.
   6 Libiberty is free software; you can redistribute it and/or
   7 modify it under the terms of the GNU Library General Public
   8 License as published by the Free Software Foundation; either
   9 version 2 of the License, or (at your option) any later version.
  10
  11 Libiberty 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 GNU
  14 Library General Public License for more details.
  15
  16 You should have received a copy of the GNU Library General Public
  17 License along with libiberty; see the file COPYING.LIB.  If
  18 not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21 /*
  22
  23 @deftypefn Extension FILE * fopen_unlocked (const char *@var{path}, const char * @var{mode})
  24
  25 Opens and returns a @code{FILE} pointer via @code{fopen}.  If the
  26 operating system supports it, ensure that the stream is setup to avoid
  27 any multi-threaded locking.  Otherwise return the @code{FILE} pointer
  28 unchanged.
  29
  30 @end deftypefn
  31
  32 @deftypefn Extension FILE * fdopen_unlocked (int @var{fildes}, const char * @var{mode})
  33
  34 Opens and returns a @code{FILE} pointer via @code{fdopen}.  If the
  35 operating system supports it, ensure that the stream is setup to avoid
  36 any multi-threaded locking.  Otherwise return the @code{FILE} pointer
  37 unchanged.
  38
  39 @end deftypefn
  40
  41 @deftypefn Extension FILE * freopen_unlocked (const char * @var{path}, const char * @var{mode}, FILE * @var{stream})
  42
  43 Opens and returns a @code{FILE} pointer via @code{freopen}.  If the
  44 operating system supports it, ensure that the stream is setup to avoid
  45 any multi-threaded locking.  Otherwise return the @code{FILE} pointer
  46 unchanged.
  47
  48 @end deftypefn
  49
  50 */
  51
  52 #ifdef HAVE_CONFIG_H
  53 #include "config.h"
  54 #endif
  55 #include <stdio.h>
  56 #ifdef HAVE_STDIO_EXT_H
  57 #include <stdio_ext.h>
  58 #endif
  59
  60 #include "libiberty.h"
  61
  62 FILE *
  63 fopen_unlocked (const char *path, const char *mode)
  64 {
  65   FILE *const fp = fopen (path, mode);
  66 #if defined(HAVE___FSETLOCKING) && defined(FSETLOCKING_BYCALLER)
  67   if (fp)
  68     __fsetlocking (fp, FSETLOCKING_BYCALLER);
  69 #endif
  70   return fp;
  71 }
  72
  73 FILE *
  74 fdopen_unlocked (int fildes, const char *mode)
  75 {
  76   FILE *const fp = fdopen (fildes, mode);
  77 #if defined(HAVE___FSETLOCKING) && defined(FSETLOCKING_BYCALLER)
  78   if (fp)
  79     __fsetlocking (fp, FSETLOCKING_BYCALLER);
  80 #endif
  81   return fp;
  82 }
  83
  84 FILE *
  85 freopen_unlocked (const char *path, const char *mode, FILE *stream)
  86 {
  87   FILE *const fp = freopen (path, mode, stream);
  88 #if defined(HAVE___FSETLOCKING) && defined(FSETLOCKING_BYCALLER)
  89   if (fp)
  90     __fsetlocking (fp, FSETLOCKING_BYCALLER);
  91 #endif
  92   return fp;
  93 }