From e0023883c6d2e6745a19e4b48e186ed156c1fca8 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 17:19:27 +0200 Subject: Adding upstream version 2.11.2. Signed-off-by: Daniel Baumann --- gl/lib/fd-safer.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 49 insertions(+) create mode 100644 gl/lib/fd-safer.c (limited to 'gl/lib/fd-safer.c') diff --git a/gl/lib/fd-safer.c b/gl/lib/fd-safer.c new file mode 100644 index 0000000..e37b7b3 --- /dev/null +++ b/gl/lib/fd-safer.c @@ -0,0 +1,49 @@ +/* Return a safer copy of a file descriptor. + + Copyright (C) 2005-2006, 2009-2022 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 3 of the License, 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, see . */ + +/* Written by Paul Eggert. */ + +#include + +#include "unistd-safer.h" + +#include +#include + +/* 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