1 /*-
2 * Copyright (c) 1990 The Regents of the University of California.
3 * All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Chris Torek.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by the University of
19 * California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 */
36
37 #if defined(LIBC_SCCS) && !defined(lint)
38 static char sccsid[] = "@(#)funopen.c 5.2 (Berkeley) 2/5/91";
39 #endif /* LIBC_SCCS and not lint */
40
41 #include <stdio.h>
42 #include <errno.h>
43 #include "local.h"
44
45 FILE *
funopen(cookie,readfn,writefn,seekfn,closefn)46 funopen(cookie, readfn, writefn, seekfn, closefn)
47 const void *cookie;
48 int (*readfn)(), (*writefn)();
49 #if __STDC__
50 fpos_t (*seekfn)(void *cookie, fpos_t off, int whence);
51 #else
52 fpos_t (*seekfn)();
53 #endif
54 int (*closefn)();
55 {
56 register FILE *fp;
57 int flags;
58
59 if (readfn == NULL) {
60 if (writefn == NULL) { /* illegal */
61 errno = EINVAL;
62 return (NULL);
63 } else
64 flags = __SWR; /* write only */
65 } else {
66 if (writefn == NULL)
67 flags = __SRD; /* read only */
68 else
69 flags = __SRW; /* read-write */
70 }
71 if ((fp = __sfp()) == NULL)
72 return (NULL);
73 fp->_flags = flags;
74 fp->_file = -1;
75 fp->_cookie = (void *)cookie;
76 fp->_read = readfn;
77 fp->_write = writefn;
78 fp->_seek = seekfn;
79 fp->_close = closefn;
80 return (fp);
81 }
82