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 * @(#)fflush.c 8.1 (Berkeley) 6/4/93 37 * $FreeBSD: src/lib/libc/stdio/fflush.c,v 1.7 1999/08/28 00:00:58 peter Exp $ 38 * $DragonFly: src/lib/libc/stdio/fflush.c,v 1.6 2005/07/23 20:23:05 joerg Exp $ 39 */ 40 41 #include "namespace.h" 42 #include <errno.h> 43 #include <stdio.h> 44 #include "un-namespace.h" 45 #include "libc_private.h" 46 47 #include "local.h" 48 #include "priv_stdio.h" 49 50 /* 51 * Flush a single file, or (if fp is NULL) all files. 52 * MT-safe version 53 */ 54 int 55 fflush(FILE *fp) 56 { 57 int retval; 58 59 if (fp == NULL) 60 return (_fwalk(__sflush)); 61 FLOCKFILE(fp); 62 if ((fp->pub._flags & (__SWR | __SRW)) == 0) { 63 errno = EBADF; 64 retval = EOF; 65 } else 66 retval = __sflush(fp); 67 68 FUNLOCKFILE(fp); 69 return (retval); 70 } 71 72 /* 73 * Flush a single file, or (if fp is NULL) all files. 74 * Non-MT-safe version 75 */ 76 int 77 __fflush(FILE *fp) 78 { 79 int retval; 80 81 if (fp == NULL) 82 return (_fwalk(__sflush)); 83 if ((fp->pub._flags & (__SWR | __SRW)) == 0) { 84 errno = EBADF; 85 retval = EOF; 86 } else 87 retval = __sflush(fp); 88 return (retval); 89 } 90 91 int 92 __sflush(FILE *fp) 93 { 94 unsigned char *p; 95 int n, t; 96 97 t = fp->pub._flags; 98 if ((t & __SWR) == 0) 99 return (0); 100 101 if ((p = fp->_bf._base) == NULL) 102 return (0); 103 104 n = fp->pub._p - p; /* write this much */ 105 106 /* 107 * Set these immediately to avoid problems with longjmp and to allow 108 * exchange buffering (via setvbuf) in user write function. 109 */ 110 fp->pub._p = p; 111 fp->pub._w = t & (__SLBF|__SNBF) ? 0 : fp->_bf._size; 112 113 for (; n > 0; n -= t, p += t) { 114 t = (*fp->_write)(fp->_cookie, (char *)p, n); 115 if (t <= 0) { 116 fp->pub._flags |= __SERR; 117 return (EOF); 118 } 119 } 120 return (0); 121 } 122