thr_fcntl.c revision 75369 
1/*
2 * Copyright (c) 1995-1998 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 AUTHOR 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 * $FreeBSD: head/lib/libkse/thread/thr_fcntl.c 75369 2001-04-10 04:19:21Z deischen $
33 */
34#include <stdarg.h>
35#include <unistd.h>
36#include <fcntl.h>
37#include <pthread.h>
38#include "pthread_private.h"
39
40__weak_reference(__fcntl, fcntl);
41
42int
43_fcntl(int fd, int cmd,...)
44{
45	int             flags = 0;
46	int		nonblock;
47	int             oldfd;
48	int             ret;
49	va_list         ap;
50
51	/* Lock the file descriptor: */
52	if ((ret = _FD_LOCK(fd, FD_RDWR, NULL)) == 0) {
53		/* Initialise the variable argument list: */
54		va_start(ap, cmd);
55
56		/* Process according to file control command type: */
57		switch (cmd) {
58		/* Duplicate a file descriptor: */
59		case F_DUPFD:
60			/*
61			 * Get the file descriptor that the caller wants to
62			 * use:
63			 */
64			oldfd = va_arg(ap, int);
65
66			/* Initialise the file descriptor table entry: */
67			if ((ret = __sys_fcntl(fd, cmd, oldfd)) < 0) {
68			}
69			/* Initialise the file descriptor table entry: */
70			else if (_thread_fd_table_init(ret) != 0) {
71				/* Quietly close the file: */
72				__sys_close(ret);
73
74				/* Reset the file descriptor: */
75				ret = -1;
76			} else {
77				/*
78				 * Save the file open flags so that they can
79				 * be         checked later:
80				 */
81				_thread_fd_table[ret]->flags = _thread_fd_table[fd]->flags;
82			}
83			break;
84		case F_SETFD:
85			flags = va_arg(ap, int);
86			ret = __sys_fcntl(fd, cmd, flags);
87			break;
88		case F_GETFD:
89			ret = __sys_fcntl(fd, cmd, 0);
90			break;
91		case F_GETFL:
92			ret = _thread_fd_table[fd]->flags;
93			break;
94		case F_SETFL:
95			/*
96			 * Get the file descriptor flags passed by the
97			 * caller:
98			 */
99			flags = va_arg(ap, int);
100
101			/*
102			 * Check if the user wants a non-blocking file
103			 * descriptor:
104			 */
105			nonblock = flags & O_NONBLOCK;
106
107			/* Set the file descriptor flags: */
108			if ((ret = __sys_fcntl(fd, cmd, flags | O_NONBLOCK)) != 0) {
109
110			/* Get the flags so that we behave like the kernel: */
111			} else if ((flags = __sys_fcntl(fd,
112			    F_GETFL, 0)) == -1) {
113				/* Error getting flags: */
114				ret = -1;
115
116			/*
117			 * Check if the file descriptor is non-blocking
118			 * with respect to the user:
119			 */
120			} else if (nonblock)
121				/* A non-blocking descriptor: */
122				_thread_fd_table[fd]->flags = flags | O_NONBLOCK;
123			else
124				/* Save the flags: */
125				_thread_fd_table[fd]->flags = flags & ~O_NONBLOCK;
126			break;
127		default:
128			/* Might want to make va_arg use a union */
129			ret = __sys_fcntl(fd, cmd, va_arg(ap, void *));
130			break;
131		}
132
133		/* Free variable arguments: */
134		va_end(ap);
135
136		/* Unlock the file descriptor: */
137		_FD_UNLOCK(fd, FD_RDWR);
138	}
139	/* Return the completion status: */
140	return (ret);
141}
142
143int
144__fcntl(int fd, int cmd,...)
145{
146	int	ret;
147	va_list	ap;
148
149	_thread_enter_cancellation_point();
150
151	va_start(ap, cmd);
152	switch (cmd) {
153		case F_DUPFD:
154		case F_SETFD:
155		case F_SETFL:
156			ret = _fcntl(fd, cmd, va_arg(ap, int));
157			break;
158		case F_GETFD:
159		case F_GETFL:
160			ret = _fcntl(fd, cmd);
161			break;
162		default:
163			ret = _fcntl(fd, cmd, va_arg(ap, void *));
164	}
165	va_end(ap);
166
167	_thread_leave_cancellation_point();
168
169	return ret;
170}
171