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/* $OpenBSD: uthread_dup2.c,v 1.12 2008/02/02 21:44:59 kurt Exp $ */
/* PUBLIC DOMAIN <marc@snafu.org> */
#include <errno.h>
#include <unistd.h>
#ifdef _THREAD_SAFE
#include <pthread.h>
#include "pthread_private.h"
int
dup2(int fd, int newfd)
{
int ret = 0;
int saved_errno;
int *kern_pipe_fd = NULL;
if (newfd < 0 || newfd >= _thread_max_fdtsize) {
errno = EBADF;
return(-1);
}
/*
* Defer signals so another thread is not scheduled
* while we're checking and possibly moving the pipe fd.
*/
_thread_kern_sig_defer();
/* Check if newfd will collide with our internal pipe. */
if (newfd == _thread_kern_pipe[0])
kern_pipe_fd = &_thread_kern_pipe[0];
else if (newfd == _thread_kern_pipe[1])
kern_pipe_fd = &_thread_kern_pipe[1];
/* if we have a conflict move the internal pipe fd */
if (kern_pipe_fd != NULL) {
ret = _thread_sys_dup(*kern_pipe_fd);
if (ret != -1) {
*kern_pipe_fd = ret;
ret = 0;
}
}
_thread_kern_sig_undefer();
if (ret == 0) {
ret = _FD_LOCK(fd, FD_RDWR, NULL);
if (ret == 0) {
if ((ret = _FD_LOCK(newfd, FD_RDWR_CLOSE, NULL)) == 0) {
/*
* If newfd was open then drop reference
* and reset flags if needed.
*/
_thread_fs_flags_replace(newfd, NULL);
ret = _thread_sys_dup2(fd, newfd);
if (ret != -1)
if(_thread_fd_table_init(newfd, FD_INIT_DUP2,
_thread_fd_table[fd]->status_flags) == -1)
ret = -1;
/*
* If the dup2 or the _thread_fd_table_init
* failed we've already removed the status
* flags, so finish closing newfd. Return
* the current errno in case the sys_close
* fails too.
*/
if (ret == -1) {
saved_errno = errno;
_SPINLOCK(&_thread_fd_table[newfd]->lock);
_thread_fd_entry_close(newfd);
_thread_sys_close(newfd);
_SPINUNLOCK(&_thread_fd_table[newfd]->lock);
errno = saved_errno ;
}
_FD_UNLOCK(newfd, FD_RDWR_CLOSE);
}
_FD_UNLOCK(fd, FD_RDWR);
}
}
return (ret);
}
#endif
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