From fe856aa957978504137c1d425815d4ed8a22be40 Mon Sep 17 00:00:00 2001 From: Ton Voon Date: Wed, 24 Jan 2007 22:47:25 +0000 Subject: Sync with gnulib - lots of extraneous code removed in preference to GNU code git-svn-id: https://nagiosplug.svn.sourceforge.net/svnroot/nagiosplug/nagiosplug/trunk@1580 f882894a-f735-0410-b71e-b25c423dba1c --- gl/fd-safer.c | 57 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+) create mode 100644 gl/fd-safer.c (limited to 'gl/fd-safer.c') diff --git a/gl/fd-safer.c b/gl/fd-safer.c new file mode 100644 index 00000000..256bfa4a --- /dev/null +++ b/gl/fd-safer.c @@ -0,0 +1,57 @@ +/* Return a safer copy of a file descriptor. + + Copyright (C) 2005, 2006 Free Software Foundation, Inc. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2, or (at your option) + any later version. + + This program 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 General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software Foundation, + Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ + +/* Written by Paul Eggert. */ + +#include + +#include "unistd-safer.h" + +#include + +#include +#ifndef STDIN_FILENO +# define STDIN_FILENO 0 +#endif +#ifndef STDERR_FILENO +# define STDERR_FILENO 2 +#endif + +/* Return FD, unless FD would be a copy of standard input, output, or + error; in that case, return a duplicate of FD, closing FD. On + failure to duplicate, close FD, set errno, and return -1. Preserve + errno if FD is negative, so that the caller can always inspect + errno when the returned value is negative. + + This function is usefully wrapped around functions that return file + descriptors, e.g., fd_safer (open ("file", O_RDONLY)). */ + +int +fd_safer (int fd) +{ + if (STDIN_FILENO <= fd && fd <= STDERR_FILENO) + { + int f = dup_safer (fd); + int e = errno; + close (fd); + errno = e; + fd = f; + } + + return fd; +} -- cgit v1.2.3-74-g34f1