thr_fcntl.c revision 56698 
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 56698 2000-01-27 23:07:25Z jasone $
33 */
34#include <stdarg.h>
35#include <unistd.h>
36#include <fcntl.h>
37#ifdef _THREAD_SAFE
38#include <pthread.h>
39#include "pthread_private.h"
40
41int
42_fcntl(int fd, int cmd,...)
43{
44	int             flags = 0;
45	int		nonblock;
46	int             oldfd;
47	int             ret;
48	va_list         ap;
49
50	/* Lock the file descriptor: */
51	if ((ret = _FD_LOCK(fd, FD_RDWR, NULL)) == 0) {
52		/* Initialise the variable argument list: */
53		va_start(ap, cmd);
54
55		/* Process according to file control command type: */
56		switch (cmd) {
57		/* Duplicate a file descriptor: */
58		case F_DUPFD:
59			/*
60			 * Get the file descriptor that the caller wants to
61			 * use:
62			 */
63			oldfd = va_arg(ap, int);
64
65			/* Initialise the file descriptor table entry: */
66			if ((ret = _thread_sys_fcntl(fd, cmd, oldfd)) < 0) {
67			}
68			/* Initialise the file descriptor table entry: */
69			else if (_thread_fd_table_init(ret) != 0) {
70				/* Quietly close the file: */
71				_thread_sys_close(ret);
72
73				/* Reset the file descriptor: */
74				ret = -1;
75			} else {
76				/*
77				 * Save the file open flags so that they can
78				 * be         checked later:
79				 */
80				_thread_fd_table[ret]->flags = _thread_fd_table[fd]->flags;
81			}
82			break;
83		case F_SETFD:
84			flags = va_arg(ap, int);
85			ret = _thread_sys_fcntl(fd, cmd, flags);
86			break;
87		case F_GETFD:
88			ret = _thread_sys_fcntl(fd, cmd, 0);
89			break;
90		case F_GETFL:
91			ret = _thread_fd_table[fd]->flags;
92			break;
93		case F_SETFL:
94			/*
95			 * Get the file descriptor flags passed by the
96			 * caller:
97			 */
98			flags = va_arg(ap, int);
99
100			/*
101			 * Check if the user wants a non-blocking file
102			 * descriptor:
103			 */
104			nonblock = flags & O_NONBLOCK;
105
106			/* Set the file descriptor flags: */
107			if ((ret = _thread_sys_fcntl(fd, cmd, flags | O_NONBLOCK)) != 0) {
108
109			/* Get the flags so that we behave like the kernel: */
110			} else if ((flags = _thread_sys_fcntl(fd,
111			    F_GETFL, 0)) == -1) {
112				/* Error getting flags: */
113				ret = -1;
114
115			/*
116			 * Check if the file descriptor is non-blocking
117			 * with respect to the user:
118			 */
119			} else if (nonblock)
120				/* A non-blocking descriptor: */
121				_thread_fd_table[fd]->flags = flags | O_NONBLOCK;
122			else
123				/* Save the flags: */
124				_thread_fd_table[fd]->flags = flags & ~O_NONBLOCK;
125			break;
126		default:
127			/* Might want to make va_arg use a union */
128			ret = _thread_sys_fcntl(fd, cmd, va_arg(ap, void *));
129			break;
130		}
131
132		/* Free variable arguments: */
133		va_end(ap);
134
135		/* Unlock the file descriptor: */
136		_FD_UNLOCK(fd, FD_RDWR);
137	}
138	/* Return the completion status: */
139	return (ret);
140}
141
142int
143fcntl(int fd, int cmd,...)
144{
145	int	ret;
146	va_list	ap;
147
148	_thread_enter_cancellation_point();
149
150	va_start(ap, cmd);
151	switch (cmd) {
152		case F_DUPFD:
153		case F_SETFD:
154		case F_SETFL:
155			ret = fcntl(fd, cmd, va_arg(ap, int));
156			break;
157		case F_GETFD:
158		case F_GETFL:
159			ret = fcntl(fd, cmd);
160			break;
161		default:
162			ret = fcntl(fd, cmd, va_arg(ap, void *));
163	}
164	va_end(ap);
165
166	_thread_leave_cancellation_point();
167
168	return ret;
169}
170#endif
171