funopen.c revision 1.4
1/* $NetBSD: funopen.c,v 1.4 1995/02/02 02:09:44 jtc Exp $ */ 2 3/*- 4 * Copyright (c) 1990, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Chris Torek. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 */ 38 39#if defined(LIBC_SCCS) && !defined(lint) 40#if 0 41static char sccsid[] = "@(#)funopen.c 8.1 (Berkeley) 6/4/93"; 42#endif 43static char rcsid[] = "$NetBSD: funopen.c,v 1.4 1995/02/02 02:09:44 jtc Exp $"; 44#endif /* LIBC_SCCS and not lint */ 45 46#include <stdio.h> 47#include <errno.h> 48#include "local.h" 49 50FILE * 51funopen(cookie, readfn, writefn, seekfn, closefn) 52 const void *cookie; 53 int (*readfn)(), (*writefn)(); 54#if __STDC__ 55 fpos_t (*seekfn)(void *cookie, fpos_t off, int whence); 56#else 57 fpos_t (*seekfn)(); 58#endif 59 int (*closefn)(); 60{ 61 register FILE *fp; 62 int flags; 63 64 if (readfn == NULL) { 65 if (writefn == NULL) { /* illegal */ 66 errno = EINVAL; 67 return (NULL); 68 } else 69 flags = __SWR; /* write only */ 70 } else { 71 if (writefn == NULL) 72 flags = __SRD; /* read only */ 73 else 74 flags = __SRW; /* read-write */ 75 } 76 if ((fp = __sfp()) == NULL) 77 return (NULL); 78 fp->_flags = flags; 79 fp->_file = -1; 80 fp->_cookie = (void *)cookie; 81 fp->_read = readfn; 82 fp->_write = writefn; 83 fp->_seek = seekfn; 84 fp->_close = closefn; 85 return (fp); 86} 87