stdio.c (3236B)
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 * 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 rcsid[] = "$OpenBSD: stdio.c,v 1.3 1997/11/09 23:40:41 flipk Exp $"; 39 #endif /* LIBC_SCCS and not lint */ 40 41 #include <fcntl.h> 42 #include <unistd.h> 43 #include <stdio.h> 44 #include "local.h" 45 46 /* 47 * Small standard I/O/seek/close functions. 48 * These maintain the `known seek offset' for seek optimisation. 49 */ 50 int 51 __sread(cookie, buf, n) 52 void *cookie; 53 char *buf; 54 int n; 55 { 56 register FILE *fp = cookie; 57 register int ret; 58 59 ret = read(fp->_file, buf, n); 60 /* if the read succeeded, update the current offset */ 61 if (ret >= 0) 62 fp->_offset += ret; 63 else 64 fp->_flags &= ~__SOFF; /* paranoia */ 65 return (ret); 66 } 67 68 int 69 __swrite(cookie, buf, n) 70 void *cookie; 71 char const *buf; 72 int n; 73 { 74 register FILE *fp = cookie; 75 76 if (fp->_flags & __SAPP) 77 (void) lseek(fp->_file, (off_t)0, SEEK_END); 78 fp->_flags &= ~__SOFF; /* in case FAPPEND mode is set */ 79 return (write(fp->_file, buf, n)); 80 } 81 82 fpos_t 83 __sseek(cookie, offset, whence) 84 void *cookie; 85 fpos_t offset; 86 int whence; 87 { 88 register FILE *fp = cookie; 89 register off_t ret; 90 91 ret = lseek(fp->_file, (off_t)offset, whence); 92 if (ret == (off_t)-1) 93 fp->_flags &= ~__SOFF; 94 else { 95 fp->_flags |= __SOFF; 96 fp->_offset = ret; 97 } 98 return (ret); 99 } 100 101 int 102 __sclose(cookie) 103 void *cookie; 104 { 105 106 return (close(((FILE *)cookie)->_file)); 107 }