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/*
* Copyright (c) 1995-1998 John Birrell <jb@cimlogic.com.au>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by John Birrell.
* 4. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
#include <errno.h>
#include <unistd.h>
#ifdef _THREAD_SAFE
#include <pthread.h>
#include "pthread_private.h"
int
dup2(int fd, int newfd)
{
int ret;
int newfd_opened;
/* Check if the file descriptor is out of range: */
if (newfd < 0 || newfd >= _thread_dtablesize) {
/* Return a bad file descriptor error: */
errno = EBADF;
ret = -1;
}
/* Lock the file descriptor: */
else if ((ret = _FD_LOCK(fd, FD_RDWR, NULL)) == 0) {
/* Lock the file descriptor: */
if (!(newfd_opened = (_thread_fd_table[newfd] != NULL)) ||
(ret = _FD_LOCK(newfd, FD_RDWR, NULL)) == 0) {
/* Perform the 'dup2' syscall: */
if ((ret = _thread_sys_dup2(fd, newfd)) < 0) {
}
/* Initialise the file descriptor table entry: */
else if (_thread_fd_table_init(ret) != 0) {
/* Quietly close the file: */
_thread_sys_close(ret);
/* Reset the file descriptor: */
ret = -1;
} else {
/*
* Save the file open flags so that they can
* be checked later:
*/
_thread_fd_table[ret]->flags = _thread_fd_table[fd]->flags;
}
/* Unlock the file descriptor: */
if (newfd_opened)
_FD_UNLOCK(newfd, FD_RDWR);
}
/* Unlock the file descriptor: */
_FD_UNLOCK(fd, FD_RDWR);
}
/* Return the completion status: */
return (ret);
}
#endif
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