1 /*	$OpenBSD: uthread_readv.c,v 1.7 2004/11/30 00:14:51 pat Exp $	*/
2 /*
3  * Copyright (c) 1995-1998 John Birrell <jb@cimlogic.com.au>
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. All advertising materials mentioning features or use of this software
15  *    must display the following acknowledgement:
16  *	This product includes software developed by John Birrell.
17  * 4. Neither the name of the author nor the names of any co-contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * $FreeBSD: uthread_readv.c,v 1.8 1999/08/28 00:03:43 peter Exp $
34  *
35  */
36 #include <sys/types.h>
37 #include <sys/fcntl.h>
38 #include <sys/uio.h>
39 #include <errno.h>
40 #include <unistd.h>
41 #ifdef _THREAD_SAFE
42 #include <pthread.h>
43 #include "pthread_private.h"
44 
45 ssize_t
readv(int fd,const struct iovec * iov,int iovcnt)46 readv(int fd, const struct iovec * iov, int iovcnt)
47 {
48 	struct pthread	*curthread = _get_curthread();
49 	ssize_t	ret;
50 	int	type;
51 
52 	/* This is a cancellation point: */
53 	_thread_enter_cancellation_point();
54 
55 	/* Lock the file descriptor for read: */
56 	if ((ret = _FD_LOCK(fd, FD_READ, NULL)) == 0) {
57 		/* Get the read/write mode type: */
58 		type = _thread_fd_table[fd]->flags & O_ACCMODE;
59 
60 		/* Check if the file is not open for read: */
61 		if (type != O_RDONLY && type != O_RDWR) {
62 			/* File is not open for read: */
63 			errno = EBADF;
64 			_FD_UNLOCK(fd, FD_READ);
65 			_thread_leave_cancellation_point();
66 			return (-1);
67 		}
68 
69 		/* Perform a non-blocking readv syscall: */
70 		while ((ret = _thread_sys_readv(fd, iov, iovcnt)) < 0) {
71 			if ((_thread_fd_table[fd]->flags & O_NONBLOCK) == 0 &&
72 			    (errno == EWOULDBLOCK || errno == EAGAIN)) {
73 				curthread->data.fd.fd = fd;
74 				_thread_kern_set_timeout(NULL);
75 
76 				/* Reset the interrupted operation flag: */
77 				curthread->interrupted = 0;
78 
79 				_thread_kern_sched_state(PS_FDR_WAIT,
80 				    __FILE__, __LINE__);
81 
82 				/*
83 				 * Check if the operation was
84 				 * interrupted by a signal
85 				 */
86 				if (curthread->interrupted) {
87 					errno = EINTR;
88 					ret = -1;
89 					break;
90 				}
91 			} else {
92 				break;
93 			}
94 		}
95 		_FD_UNLOCK(fd, FD_READ);
96 	}
97 
98 	/* No longer in a cancellation point: */
99 	_thread_leave_cancellation_point();
100 
101 	return (ret);
102 }
103 #endif
104