1 /*- 2 * Copyright (c) 1990 The Regents of the University of California. 3 * 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 37 #if defined(LIBC_SCCS) && !defined(lint) 38 /*static char *sccsid = "from: @(#)fread.c 5.4 (Berkeley) 5/4/91";*/ 39 static char *rcsid = "$Id: fread.c,v 1.5 1993/12/14 23:17:09 jtc Exp $"; 40 #endif /* LIBC_SCCS and not lint */ 41 42 #include <stdio.h> 43 #include <string.h> 44 45 size_t 46 fread(buf, size, count, fp) 47 void *buf; 48 size_t size, count; 49 register FILE *fp; 50 { 51 register size_t resid; 52 register char *p; 53 register int r; 54 size_t total; 55 56 if ((resid = count * size) == 0) 57 return (0); 58 if (fp->_r < 0) 59 fp->_r = 0; 60 total = resid; 61 p = buf; 62 while (resid > (r = fp->_r)) { 63 (void) bcopy((void *)fp->_p, (void *)p, (size_t)r); 64 fp->_p += r; 65 /* fp->_r = 0 ... done in __srefill */ 66 p += r; 67 resid -= r; 68 if (__srefill(fp)) { 69 /* no more input: return partial result */ 70 return ((total - resid) / size); 71 } 72 } 73 (void) bcopy((void *)fp->_p, (void *)p, resid); 74 fp->_r -= resid; 75 fp->_p += resid; 76 return (count); 77 } 78