xref: /dflybsd-src/lib/libc/stdio/sreadahead.c (revision dc6df0be9981bbfad8c62ebbe41d842dd7d81b15)
1*dc6df0beSMatthew Dillon /*
2*dc6df0beSMatthew Dillon  * Copyright (c) 2008 The DragonFly Project.  All rights reserved.
3*dc6df0beSMatthew Dillon  *
4*dc6df0beSMatthew Dillon  * This code is derived from software contributed to The DragonFly Project
5*dc6df0beSMatthew Dillon  * by Matthew Dillon <dillon@backplane.com>
6*dc6df0beSMatthew Dillon  *
7*dc6df0beSMatthew Dillon  * Redistribution and use in source and binary forms, with or without
8*dc6df0beSMatthew Dillon  * modification, are permitted provided that the following conditions
9*dc6df0beSMatthew Dillon  * are met:
10*dc6df0beSMatthew Dillon  *
11*dc6df0beSMatthew Dillon  * 1. Redistributions of source code must retain the above copyright
12*dc6df0beSMatthew Dillon  *    notice, this list of conditions and the following disclaimer.
13*dc6df0beSMatthew Dillon  * 2. Redistributions in binary form must reproduce the above copyright
14*dc6df0beSMatthew Dillon  *    notice, this list of conditions and the following disclaimer in
15*dc6df0beSMatthew Dillon  *    the documentation and/or other materials provided with the
16*dc6df0beSMatthew Dillon  *    distribution.
17*dc6df0beSMatthew Dillon  * 3. Neither the name of The DragonFly Project nor the names of its
18*dc6df0beSMatthew Dillon  *    contributors may be used to endorse or promote products derived
19*dc6df0beSMatthew Dillon  *    from this software without specific, prior written permission.
20*dc6df0beSMatthew Dillon  *
21*dc6df0beSMatthew Dillon  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22*dc6df0beSMatthew Dillon  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23*dc6df0beSMatthew Dillon  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24*dc6df0beSMatthew Dillon  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
25*dc6df0beSMatthew Dillon  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26*dc6df0beSMatthew Dillon  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27*dc6df0beSMatthew Dillon  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28*dc6df0beSMatthew Dillon  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29*dc6df0beSMatthew Dillon  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30*dc6df0beSMatthew Dillon  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31*dc6df0beSMatthew Dillon  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32*dc6df0beSMatthew Dillon  * SUCH DAMAGE.
33*dc6df0beSMatthew Dillon  *
34*dc6df0beSMatthew Dillon  * $DragonFly: src/lib/libc/stdio/sreadahead.c,v 1.1 2008/04/15 01:16:14 dillon Exp $
35*dc6df0beSMatthew Dillon  */
36*dc6df0beSMatthew Dillon /*
37*dc6df0beSMatthew Dillon  * This is an externalized internal function that the M4 package needs.
38*dc6df0beSMatthew Dillon  * It was easiest just to throw it into lib.
39*dc6df0beSMatthew Dillon  */
40*dc6df0beSMatthew Dillon 
41*dc6df0beSMatthew Dillon #include "namespace.h"
42*dc6df0beSMatthew Dillon #include <stdio.h>
43*dc6df0beSMatthew Dillon #include <stdlib.h>
44*dc6df0beSMatthew Dillon #include <string.h>
45*dc6df0beSMatthew Dillon #include "un-namespace.h"
46*dc6df0beSMatthew Dillon 
47*dc6df0beSMatthew Dillon #include "local.h"
48*dc6df0beSMatthew Dillon #include "libc_private.h"
49*dc6df0beSMatthew Dillon #include "priv_stdio.h"
50*dc6df0beSMatthew Dillon 
51*dc6df0beSMatthew Dillon size_t
52*dc6df0beSMatthew Dillon __sreadahead(FILE *fp)
53*dc6df0beSMatthew Dillon {
54*dc6df0beSMatthew Dillon 	size_t count;
55*dc6df0beSMatthew Dillon 
56*dc6df0beSMatthew Dillon 	count = fp->pub._r;
57*dc6df0beSMatthew Dillon 	if (HASUB(fp))
58*dc6df0beSMatthew Dillon 		count += fp->_ur;
59*dc6df0beSMatthew Dillon 	return(count);
60*dc6df0beSMatthew Dillon }
61*dc6df0beSMatthew Dillon 
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