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 * @(#)stdio.c 8.1 (Berkeley) 6/4/93 33 * $FreeBSD: src/lib/libc/stdio/stdio.c,v 1.28 2008/05/05 16:14:02 jhb Exp $ 34 * $DragonFly: src/lib/libc/stdio/stdio.c,v 1.7 2005/11/20 11:07:30 swildner Exp $ 35 */ 36 37 #include "namespace.h" 38 #include <errno.h> 39 #include <fcntl.h> 40 #include <limits.h> 41 #include <stdio.h> 42 #include <stdlib.h> 43 #include <unistd.h> 44 #include "un-namespace.h" 45 #include "local.h" 46 #include "priv_stdio.h" 47 48 /* 49 * Small standard I/O/seek/close functions. 50 */ 51 int 52 __sread(void *cookie, char *buf, int n) 53 { 54 FILE *fp = cookie; 55 56 return(_read(fp->pub._fileno, buf, (size_t)n)); 57 } 58 59 int 60 __swrite(void *cookie, const char *buf, int n) 61 { 62 FILE *fp = cookie; 63 64 return (_write(fp->pub._fileno, buf, (size_t)n)); 65 } 66 67 fpos_t 68 __sseek(void *cookie, fpos_t offset, int whence) 69 { 70 FILE *fp = cookie; 71 72 return (lseek(fp->pub._fileno, (off_t)offset, whence)); 73 } 74 75 int 76 __sclose(void *cookie) 77 { 78 79 return (_close(((FILE *)cookie)->pub._fileno)); 80 } 81 82 /* 83 * Higher level wrappers. 84 */ 85 int 86 _sread(FILE *fp, char *buf, int n) 87 { 88 int ret; 89 90 ret = (*fp->_read)(fp->_cookie, buf, n); 91 if (ret > 0) { 92 if (fp->pub._flags & __SOFF) { 93 if (fp->_offset <= OFF_MAX - ret) 94 fp->_offset += ret; 95 else 96 fp->pub._flags &= ~__SOFF; 97 } 98 } else if (ret < 0) 99 fp->pub._flags &= ~__SOFF; 100 return (ret); 101 } 102 103 int 104 _swrite(FILE *fp, const char *buf, int n) 105 { 106 int ret; 107 int serrno; 108 109 if (fp->pub._flags & __SAPP) { 110 serrno = errno; 111 if (_sseek(fp, (fpos_t)0, SEEK_END) == -1 && 112 (fp->pub._flags & __SOPT)) 113 return (-1); 114 errno = serrno; 115 } 116 ret = (*fp->_write)(fp->_cookie, buf, n); 117 /* __SOFF removed even on success in case O_APPEND mode is set. */ 118 if (ret >= 0) { 119 if ((fp->pub._flags & (__SAPP|__SOFF)) == (__SAPP|__SOFF) && 120 fp->_offset <= OFF_MAX - ret) 121 fp->_offset += ret; 122 else 123 fp->pub._flags &= ~__SOFF; 124 125 } else if (ret < 0) 126 fp->pub._flags &= ~__SOFF; 127 return (ret); 128 } 129 130 fpos_t 131 _sseek(FILE *fp, fpos_t offset, int whence) 132 { 133 fpos_t ret; 134 int serrno, errret; 135 136 serrno = errno; 137 errno = 0; 138 ret = (*fp->_seek)(fp->_cookie, offset, whence); 139 errret = errno; 140 if (errno == 0) 141 errno = serrno; 142 /* 143 * Disallow negative seeks per POSIX. 144 * It is needed here to help upper level caller 145 * in the cases it can't detect. 146 */ 147 if (ret < 0) { 148 if (errret == 0) { 149 if (offset != 0 || whence != SEEK_CUR) { 150 if (HASUB(fp)) 151 FREEUB(fp); 152 fp->pub._p = fp->_bf._base; 153 fp->pub._r = 0; 154 fp->pub._flags &= ~__SEOF; 155 } 156 fp->pub._flags |= __SERR; 157 errno = EINVAL; 158 } else if (errret == ESPIPE) 159 fp->pub._flags &= ~__SAPP; 160 fp->pub._flags &= ~__SOFF; 161 ret = -1; 162 } else if (fp->pub._flags & __SOPT) { 163 fp->pub._flags |= __SOFF; 164 fp->_offset = ret; 165 } 166 return (ret); 167 } 168