lib/libc/stdio/funopen.c

   1 /*-
   2  * Copyright (c) 1990, 1993
   3  *      The Regents of the University of California.  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  * $FreeBSD: src/lib/libc/stdio/funopen.c,v 1.1.1.1.14.1 2001/03/05 10:57:52 obrien Exp $
  37  * $DragonFly: src/lib/libc/stdio/funopen.c,v 1.5 2005/07/23 20:23:06 joerg Exp $
  38  *
  39  * @(#)funopen.c        8.1 (Berkeley) 6/4/93
  40  */
  41
  42 #include <stdio.h>
  43 #include <errno.h>
  44
  45 #include "local.h"
  46 #include "priv_stdio.h"
  47
  48 FILE *
  49 funopen(const void *cookie, int (*readfn)(void *, char *, int),
  50         int (*writefn)(void *, const char *, int),
  51         fpos_t (*seekfn)(void *cookie, fpos_t off, int whence),
  52         int (*closefn)(void *))
  53 {
  54         FILE *fp;
  55         int flags;
  56
  57         if (readfn == NULL) {
  58                 if (writefn == NULL) {          /* illegal */
  59                         errno = EINVAL;
  60                         return (NULL);
  61                 } else
  62                         flags = __SWR;          /* write only */
  63         } else {
  64                 if (writefn == NULL)
  65                         flags = __SRD;          /* read only */
  66                 else
  67                         flags = __SRW;          /* read-write */
  68         }
  69         if ((fp = __sfp()) == NULL)
  70                 return (NULL);
  71         fp->pub._flags = flags;
  72         fp->pub._fileno = -1;
  73         fp->_cookie = (void *)cookie;
  74         fp->_read = readfn;
  75         fp->_write = writefn;
  76         fp->_seek = seekfn;
  77         fp->_close = closefn;
  78         return (fp);
  79 }