| 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 | |
