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 | * 4. Neither the name of the University nor the names of its contributors␊ |
17 | * may be used to endorse or promote products derived from this software␊ |
18 | * without specific prior written permission.␊ |
19 | *␊ |
20 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND␊ |
21 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE␊ |
22 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE␊ |
23 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE␊ |
24 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL␊ |
25 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS␊ |
26 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)␊ |
27 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT␊ |
28 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY␊ |
29 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF␊ |
30 | * SUCH DAMAGE.␊ |
31 | */␊ |
32 | ␊ |
33 | #if defined(LIBC_SCCS) && !defined(lint)␊ |
34 | static char sccsid[] = "@(#)fread.c␉8.2 (Berkeley) 12/11/93";␊ |
35 | #endif /* LIBC_SCCS and not lint */␊ |
36 | #include <sys/cdefs.h>␊ |
37 | __FBSDID("$FreeBSD: src/lib/libc/stdio/fread.c,v 1.16 2009/07/12 13:09:43 ed Exp $");␊ |
38 | ␊ |
39 | #include "namespace.h"␊ |
40 | #include <stdio.h>␊ |
41 | #include <string.h>␊ |
42 | #include "un-namespace.h"␊ |
43 | #include "local.h"␊ |
44 | ␊ |
45 | ␊ |
46 | ␊ |
47 | ␊ |
48 | size_t␊ |
49 | fread(void * __restrict buf, size_t size, size_t count, FILE * __restrict fp)␊ |
50 | {␊ |
51 | ␉size_t ret;␊ |
52 | ␊ |
53 | ␉ret = __fread(buf, size, count, fp);␊ |
54 | ␉return (ret);␊ |
55 | }␊ |
56 | ␊ |
57 | size_t␊ |
58 | __fread(void * __restrict buf, size_t size, size_t count, FILE * __restrict fp)␊ |
59 | {␊ |
60 | ␉size_t resid;␊ |
61 | ␉char *p;␊ |
62 | ␉int r, ret;␊ |
63 | ␉size_t total;␊ |
64 | ␊ |
65 | ␉/*␊ |
66 | ␉ * ANSI and SUSv2 require a return value of 0 if size or count are 0.␊ |
67 | ␉ */␊ |
68 | ␉if ((resid = count * size) == 0)␊ |
69 | ␉␉return (0);␊ |
70 | ␉ORIENT(fp, -1);␊ |
71 | ␉if (fp->_r < 0)␊ |
72 | ␉␉fp->_r = 0;␊ |
73 | ␉total = resid;␊ |
74 | ␉p = buf;␊ |
75 | ␉/* first deal with anything left in buffer, plus any ungetc buffers */␊ |
76 | ␉while (resid > (r = fp->_r)) {␊ |
77 | ␉␉(void)memcpy((void *)p, (void *)fp->_p, (size_t)r);␊ |
78 | ␉␉fp->_p += r;␊ |
79 | ␉␉/* fp->_r = 0 ... done in __srefill */␊ |
80 | ␉␉p += r;␊ |
81 | ␉␉resid -= r;␊ |
82 | ␉␉if ((ret = __srefill0(fp)) > 0)␊ |
83 | ␉␉␉break;␊ |
84 | ␉␉else if (ret) {␊ |
85 | ␉␉␉/* no more input: return partial result */␊ |
86 | ␉␉␉return ((total - resid) / size);␊ |
87 | ␉␉}␊ |
88 | ␉}␊ |
89 | ␉/*␊ |
90 | ␉ * 5980080: don't use optimization if __SMBF not set (meaning setvbuf␊ |
91 | ␉ * was called, and the buffer belongs to the user).␊ |
92 | ␉ * 6180417: but for unbuffered (__SMBF is not set), so specifically␊ |
93 | ␉ * test for it.␊ |
94 | ␉ */␊ |
95 | ␉if ((fp->_flags & (__SMBF | __SNBF)) && resid > fp->_bf._size) {␊ |
96 | ␉␉struct __sbuf save;␊ |
97 | ␉␉size_t n;␊ |
98 | ␊ |
99 | ␉␉save = fp->_bf;␊ |
100 | ␉␉fp->_bf._base = (unsigned char␉*)p;␊ |
101 | ␉␉fp->_bf._size = resid;␊ |
102 | ␉␉while (fp->_bf._size > 0) {␊ |
103 | ␉␉␉if ((ret = __srefill1(fp)) != 0) {␊ |
104 | ␉␉␉␉/* no more input: return partial result */␊ |
105 | ␉␉␉␉resid = fp->_bf._size;␊ |
106 | ␉␉␉␉fp->_bf = save;␊ |
107 | ␉␉␉␉fp->_p = fp->_bf._base;␊ |
108 | ␉␉␉␉/* fp->_r = 0; already set in __srefill1 */␊ |
109 | ␉␉␉␉return ((total - resid) / size);␊ |
110 | ␉␉␉}␊ |
111 | ␉␉␉fp->_bf._base += fp->_r;␊ |
112 | ␉␉␉fp->_bf._size -= fp->_r;␊ |
113 | ␉␉}␊ |
114 | ␉␉fp->_bf = save;␊ |
115 | ␉␉n = fp->_bf._size * ((resid - 1) / fp->_bf._size);␊ |
116 | ␉␉r = resid - n;␊ |
117 | ␉␉(void)memcpy((void *)fp->_bf._base, (void *)(p + n), (size_t)r);␊ |
118 | ␉␉fp->_p = fp->_bf._base + r;␊ |
119 | ␉␉fp->_r = 0;␊ |
120 | ␉} else {␊ |
121 | ␉␉while (resid > (r = fp->_r)) {␊ |
122 | ␉␉␉(void)memcpy((void *)p, (void *)fp->_p, (size_t)r);␊ |
123 | ␉␉␉fp->_p += r;␊ |
124 | ␉␉␉/* fp->_r = 0 ... done in __srefill */␊ |
125 | ␉␉␉p += r;␊ |
126 | ␉␉␉resid -= r;␊ |
127 | ␉␉␉if (__srefill1(fp)) {␊ |
128 | ␉␉␉␉/* no more input: return partial result */␊ |
129 | ␉␉␉␉return ((total - resid) / size);␊ |
130 | ␉␉␉}␊ |
131 | ␉␉}␊ |
132 | ␉␉(void)memcpy((void *)p, (void *)fp->_p, resid);␊ |
133 | ␉␉fp->_r -= resid;␊ |
134 | ␉␉fp->_p += resid;␊ |
135 | ␉}␊ |
136 | ␉return (count);␊ |
137 | }␊ |
138 | |