thr_read.c revision 13546 
1/*
2 * Copyright (c) 1995 John Birrell <jb@cimlogic.com.au>.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by John Birrell.
16 * 4. Neither the name of the author nor the names of any co-contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 *
32 */
33#include <sys/types.h>
34#include <sys/fcntl.h>
35#include <sys/uio.h>
36#include <errno.h>
37#include <unistd.h>
38#ifdef _THREAD_SAFE
39#include <pthread.h>
40#include "pthread_private.h"
41
42ssize_t
43read(int fd, void *buf, size_t nbytes)
44{
45	int             nonblock;
46	int             ret;
47	int             status;
48	if (fd < 0 || fd > _thread_dtablesize || _thread_fd_table[fd] == NULL) {
49		_thread_seterrno(_thread_run, EBADF);
50		ret = -1;
51	} else if ((nonblock = _thread_fd_table[fd]->flags & O_NONBLOCK) == 0 && (ret = _thread_fd_lock(fd, FD_READ, NULL, __FILE__, __LINE__)) != 0) {
52		/* Cannot lock file descriptor. */
53	} else {
54		while ((ret = _thread_sys_read(fd, buf, nbytes)) < 0) {
55			if (nonblock == 0 && (errno == EWOULDBLOCK || errno == EAGAIN)) {
56				_thread_kern_sig_block(&status);
57				_thread_run->data.fd.fd = fd;
58				_thread_kern_set_timeout(NULL);
59				_thread_kern_sched_state(PS_FDR_WAIT, __FILE__, __LINE__);
60				if (errno == EINTR) {
61					ret = -1;
62					break;
63				}
64			} else {
65				break;
66			}
67		}
68		if (nonblock == 0) {
69			_thread_fd_unlock(fd, FD_READ);
70		}
71	}
72	return (ret);
73}
74#endif
75