1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 /* Copyright (c) 1988 AT&T */ 28 /* All Rights Reserved */ 29 30 #pragma ident "%Z%%M% %I% %E% SMI" 31 32 #include "lint.h" 33 #include "file64.h" 34 #include "mtlib.h" 35 #include <stdio.h> 36 #include <stddef.h> 37 #include <values.h> 38 #include <memory.h> 39 #include <thread.h> 40 #include <synch.h> 41 #include <errno.h> 42 #include <sys/types.h> 43 #include "stdiom.h" 44 #include "mse.h" 45 46 size_t 47 fread(void *ptr, size_t size, size_t count, FILE *iop) 48 { 49 ssize_t s; 50 int c; 51 char *dptr = (char *)ptr; 52 rmutex_t *lk; 53 54 FLOCKFILE(lk, iop); 55 56 _SET_ORIENTATION_BYTE(iop); 57 58 /* is it a readable stream */ 59 if (!(iop->_flag & (_IOREAD | _IORW))) { 60 iop->_flag |= _IOERR; 61 errno = EBADF; 62 FUNLOCKFILE(lk); 63 return (0); 64 } 65 66 if (iop->_flag & _IOEOF) { 67 FUNLOCKFILE(lk); 68 return (0); 69 } 70 71 /* These checks are here to avoid the multiply */ 72 if (count == 1) 73 s = size; 74 else if (size == 1) 75 s = count; 76 else 77 s = size * count; 78 79 while (s > 0) { 80 if (iop->_cnt < s) { 81 if (iop->_cnt > 0) { 82 (void) memcpy((void*)dptr, iop->_ptr, 83 iop->_cnt); 84 dptr += iop->_cnt; 85 s -= iop->_cnt; 86 } 87 /* 88 * filbuf clobbers _cnt & _ptr, 89 * so don't waste time setting them. 90 */ 91 if ((c = __filbuf(iop)) == EOF) 92 break; 93 *dptr++ = (char)c; 94 s--; 95 } 96 if (iop->_cnt >= s) { 97 char *tmp = (char *)iop->_ptr; 98 switch (s) { 99 case 8: 100 *dptr++ = *tmp++; 101 /*FALLTHRU*/ 102 case 7: 103 *dptr++ = *tmp++; 104 /*FALLTHRU*/ 105 case 6: 106 *dptr++ = *tmp++; 107 /*FALLTHRU*/ 108 case 5: 109 *dptr++ = *tmp++; 110 /*FALLTHRU*/ 111 case 4: 112 *dptr++ = *tmp++; 113 /*FALLTHRU*/ 114 case 3: 115 *dptr++ = *tmp++; 116 /*FALLTHRU*/ 117 case 2: 118 *dptr++ = *tmp++; 119 /*FALLTHRU*/ 120 case 1: 121 *dptr++ = *tmp++; 122 break; 123 default: 124 (void) memcpy((void*)dptr, iop->_ptr, 125 (size_t)s); 126 } 127 iop->_ptr += s; 128 iop->_cnt -= s; 129 FUNLOCKFILE(lk); 130 return (count); 131 } 132 } 133 FUNLOCKFILE(lk); 134 return (size != 0 ? count - ((s + size - 1) / size) : 0); 135 } 136