1 /* $NetBSD: stdio.c,v 1.22 2013/05/19 17:07:04 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 1990, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Chris Torek. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #include <sys/cdefs.h> 36 #if defined(LIBC_SCCS) && !defined(lint) 37 #if 0 38 static char sccsid[] = "@(#)stdio.c 8.1 (Berkeley) 6/4/93"; 39 #else 40 __RCSID("$NetBSD: stdio.c,v 1.22 2013/05/19 17:07:04 christos Exp $"); 41 #endif 42 #endif /* LIBC_SCCS and not lint */ 43 44 #include "namespace.h" 45 46 #include <assert.h> 47 #include <errno.h> 48 #include <fcntl.h> 49 #include <stdio.h> 50 #include <unistd.h> 51 52 #include "reentrant.h" 53 #include "local.h" 54 55 /* 56 * Small standard I/O/seek/close functions. 57 * These maintain the `known seek offset' for seek optimisation. 58 */ 59 ssize_t 60 __sread(void *cookie, void *buf, size_t n) 61 { 62 FILE *fp = cookie; 63 ssize_t ret; 64 65 _DIAGASSERT(cookie != NULL); 66 _DIAGASSERT(cookie == fp->_cookie); 67 _DIAGASSERT(buf != NULL); 68 69 ret = read(__sfileno(fp), buf, n); 70 /* if the read succeeded, update the current offset */ 71 if (ret >= 0) 72 fp->_offset += ret; 73 else 74 fp->_flags &= ~__SOFF; /* paranoia */ 75 76 return ret; 77 } 78 79 ssize_t 80 __swrite(void *cookie, const void *buf, size_t n) 81 { 82 FILE *fp = cookie; 83 84 _DIAGASSERT(cookie != NULL); 85 _DIAGASSERT(cookie == fp->_cookie); 86 _DIAGASSERT(buf != NULL); 87 88 if (fp->_flags & __SAPP) 89 if (lseek(__sfileno(fp), (off_t)0, SEEK_END) == (off_t)-1) { 90 if (errno == ESPIPE) /* if unseekable, OK, */ 91 fp->_flags &= ~__SAPP; /* all writes append. */ 92 else 93 return -1; 94 } 95 fp->_flags &= ~__SOFF; /* in case FAPPEND mode is set */ 96 return write(__sfileno(fp), buf, n); 97 } 98 99 off_t 100 __sseek(void *cookie, off_t offset, int whence) 101 { 102 FILE *fp = cookie; 103 off_t ret; 104 105 _DIAGASSERT(cookie != NULL); 106 _DIAGASSERT(cookie == fp->_cookie); 107 108 ret = lseek(__sfileno(fp), offset, whence); 109 if (ret == (off_t)-1L) 110 fp->_flags &= ~__SOFF; 111 else { 112 fp->_flags |= __SOFF; 113 fp->_offset = ret; 114 } 115 return ret; 116 } 117 118 int 119 __sclose(void *cookie) 120 { 121 FILE *fp = cookie; 122 123 _DIAGASSERT(cookie != NULL); 124 _DIAGASSERT(cookie == fp->_cookie); 125 126 return close(__sfileno(fp)); 127 } 128