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/* $OpenBSD: uthread_read.c,v 1.6 2001/08/17 06:50:25 fgsch Exp $ */
/*
* 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 AUTHOR 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.
*
* $FreeBSD: uthread_read.c,v 1.8 1999/08/28 00:03:43 peter Exp $
*
*/
#include <sys/types.h>
#include <sys/fcntl.h>
#include <sys/uio.h>
#include <errno.h>
#include <unistd.h>
#ifdef _THREAD_SAFE
#include <pthread.h>
#include "pthread_private.h"
ssize_t
read(int fd, void *buf, size_t nbytes)
{
ssize_t ret;
int type;
/* This is a cancellation point: */
_thread_enter_cancellation_point();
/* POSIX says to do just this: */
if (nbytes == 0)
ret = 0;
/* Lock the file descriptor for read: */
else if ((ret = _FD_LOCK(fd, FD_READ, NULL)) == 0) {
/* Get the read/write mode type: */
type = _thread_fd_table[fd]->flags & O_ACCMODE;
/* Check if the file is not open for read: */
if (type != O_RDONLY && type != O_RDWR) {
/* File is not open for read: */
errno = EBADF;
ret = -1;
}
/* Perform a non-blocking read syscall: */
else while ((ret = _thread_sys_read(fd, buf, nbytes)) < 0) {
if ((_thread_fd_table[fd]->flags & O_NONBLOCK) == 0 &&
(errno == EWOULDBLOCK || errno == EAGAIN)) {
_thread_run->data.fd.fd = fd;
_thread_kern_set_timeout(NULL);
/* Reset the interrupted operation flag: */
_thread_run->interrupted = 0;
_thread_kern_sched_state(PS_FDR_WAIT,
__FILE__, __LINE__);
/*
* Check if the operation was
* interrupted by a signal
*/
if (_thread_run->interrupted) {
errno = EINTR;
ret = -1;
break;
}
} else {
break;
}
}
_FD_UNLOCK(fd, FD_READ);
}
/* No longer in a cancellation point: */
_thread_leave_cancellation_point();
return (ret);
}
#endif
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