wget/lib/pipe2-safer.c

53 lines
1.4 KiB
C

/* Invoke pipe2, but avoid some glitches.
Copyright (C) 2005-2006, 2009-2019 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 <https://www.gnu.org/licenses/>. */
/* Written by Eric Blake. */
#include <config.h>
/* Specification. */
#include "unistd-safer.h"
#include <unistd.h>
#include <errno.h>
/* Like pipe2, but ensure that neither of the file descriptors is
STDIN_FILENO, STDOUT_FILENO, or STDERR_FILENO. */
int
pipe2_safer (int fd[2], int flags)
{
/* This is a generalization of the pipe_safer implementation. */
if (pipe2 (fd, flags) == 0)
{
int i;
for (i = 0; i < 2; i++)
{
fd[i] = fd_safer_flag (fd[i], flags);
if (fd[i] < 0)
{
int e = errno;
close (fd[1 - i]);
errno = e;
return -1;
}
}
return 0;
}
return -1;
}