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 5This file is part of the libiberty library. 6Libiberty is free software; you can redistribute it and/or 7modify it under the terms of the GNU Library General Public 8License as published by the Free Software Foundation; either 9version 2 of the License, or (at your option) any later version. 10 11Libiberty is distributed in the hope that it will be useful, 12but WITHOUT ANY WARRANTY; without even the implied warranty of 13MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14Library General Public License for more details. 15 16You should have received a copy of the GNU Library General Public 17License along with libiberty; see the file COPYING.LIB. If 18not, write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor, 19Boston, MA 02110-1301, USA. */ 20 21/* 22 23@deftypefn Extension void unlock_stream (FILE * @var{stream}) 24 25If the OS supports it, ensure that the supplied stream is setup to 26avoid any multi-threaded locking. Otherwise leave the @code{FILE} 27pointer unchanged. If the @var{stream} is @code{NULL} do nothing. 28 29@end deftypefn 30 31@deftypefn Extension void unlock_std_streams (void) 32 33If the OS supports it, ensure that the standard I/O streams, 34@code{stdin}, @code{stdout} and @code{stderr} are setup to avoid any 35multi-threaded locking. Otherwise do nothing. 36 37@end deftypefn 38 39@deftypefn Extension {FILE *} fopen_unlocked (const char *@var{path}, const char * @var{mode}) 40 41Opens and returns a @code{FILE} pointer via @code{fopen}. If the 42operating system supports it, ensure that the stream is setup to avoid 43any multi-threaded locking. Otherwise return the @code{FILE} pointer 44unchanged. 45 46@end deftypefn 47 48@deftypefn Extension {FILE *} fdopen_unlocked (int @var{fildes}, const char * @var{mode}) 49 50Opens and returns a @code{FILE} pointer via @code{fdopen}. If the 51operating system supports it, ensure that the stream is setup to avoid 52any multi-threaded locking. Otherwise return the @code{FILE} pointer 53unchanged. 54 55@end deftypefn 56 57@deftypefn Extension {FILE *} freopen_unlocked (const char * @var{path}, const char * @var{mode}, FILE * @var{stream}) 58 59Opens and returns a @code{FILE} pointer via @code{freopen}. If the 60operating system supports it, ensure that the stream is setup to avoid 61any multi-threaded locking. Otherwise return the @code{FILE} pointer 62unchanged. 63 64@end deftypefn 65 66*/ 67 68#ifdef HAVE_CONFIG_H 69#include "config.h" 70#endif 71#include <stdio.h> 72#ifdef HAVE_STDIO_EXT_H 73#include <stdio_ext.h> 74#endif 75 76#include "libiberty.h" 77 78/* This is an inline helper function to consolidate attempts to unlock 79 a stream. */ 80 81static inline void 82unlock_1 (FILE *const fp ATTRIBUTE_UNUSED) 83{ 84#if defined(HAVE___FSETLOCKING) && defined(FSETLOCKING_BYCALLER) 85 if (fp) 86 __fsetlocking (fp, FSETLOCKING_BYCALLER); 87#endif 88} 89 90void 91unlock_stream (FILE *fp) 92{ 93 unlock_1 (fp); 94} 95 96void 97unlock_std_streams (void) 98{ 99 unlock_1 (stdin); 100 unlock_1 (stdout); 101 unlock_1 (stderr); 102} 103 104FILE * 105fopen_unlocked (const char *path, const char *mode) 106{ 107 FILE *const fp = fopen (path, mode); 108 unlock_1 (fp); 109 return fp; 110} 111 112FILE * 113fdopen_unlocked (int fildes, const char *mode) 114{ 115 FILE *const fp = fdopen (fildes, mode); 116 unlock_1 (fp); 117 return fp; 118} 119 120FILE * 121freopen_unlocked (const char *path, const char *mode, FILE *stream) 122{ 123 FILE *const fp = freopen (path, mode, stream); 124 unlock_1 (fp); 125 return fp; 126} 127