1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
|
/*
* 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 REGENTS 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.
*
*/
#include <stdarg.h>
#include <unistd.h>
#include <fcntl.h>
#ifdef _THREAD_SAFE
#include <pthread.h>
#include "pthread_private.h"
int
fcntl(int fd, int cmd,...)
{
int flags = 0;
int nonblock;
int oldfd;
int ret;
int status;
va_list ap;
/* Lock the file descriptor: */
if ((ret = _FD_LOCK(fd, FD_RDWR, NULL)) == 0) {
/* Initialise the variable argument list: */
va_start(ap, cmd);
/* Process according to file control command type: */
switch (cmd) {
/* Duplicate a file descriptor: */
case F_DUPFD:
/*
* Get the file descriptor that the caller wants to
* use:
*/
oldfd = va_arg(ap, int);
/* Initialise the file descriptor table entry: */
if ((ret = _thread_sys_fcntl(fd, cmd, oldfd)) < 0) {
}
/* Initialise the file descriptor table entry: */
else if (_thread_fd_table_init(ret) != 0) {
/* Quietly close the file: */
_thread_sys_close(ret);
/* Reset the file descriptor: */
ret = -1;
} else {
/*
* Save the file open flags so that they can
* be checked later:
*/
_thread_fd_table[ret]->flags = _thread_fd_table[fd]->flags;
}
break;
case F_SETFD:
flags = va_arg(ap, int);
ret = _thread_sys_fcntl(fd, cmd, flags);
break;
case F_GETFD:
ret = _thread_sys_fcntl(fd, cmd, 0);
break;
case F_GETFL:
ret = _thread_fd_table[fd]->flags;
break;
case F_SETFL:
/*
* Get the file descriptor flags passed by the
* caller:
*/
flags = va_arg(ap, int);
/*
* Check if the user wants a non-blocking file
* descriptor:
*/
nonblock = flags & O_NONBLOCK;
/* Set the file descriptor flags: */
if ((ret = _thread_sys_fcntl(fd, cmd, flags | O_NONBLOCK)) != 0) {
/* Get the flags so that we behave like the kernel: */
} else if ((flags = _thread_sys_fcntl(fd,
F_GETFL, 0)) == -1) {
/* Error getting flags: */
ret = -1;
/*
* Check if the file descriptor is non-blocking
* with respect to the user:
*/
} else if (nonblock)
/* A non-blocking descriptor: */
_thread_fd_table[fd]->flags = flags | O_NONBLOCK;
else
/* Save the flags: */
_thread_fd_table[fd]->flags = flags & ~O_NONBLOCK;
break;
default:
/* Might want to make va_arg use a union */
ret = _thread_sys_fcntl(fd, cmd, va_arg(ap, void *));
break;
}
/* Free variable arguments: */
va_end(ap);
/* Unlock the file descriptor: */
_FD_UNLOCK(fd, FD_RDWR);
}
/* Return the completion status: */
return (ret);
}
#endif
|
