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 sccsid[] = "@(#)fflush.c 8.1 (Berkeley) 6/4/93"; 39 #endif /* LIBC_SCCS and not lint */ 40 #include <sys/cdefs.h> 41 __FBSDID("$FreeBSD$"); 42 43 #include "namespace.h" 44 #include <errno.h> 45 #include <stdio.h> 46 #include "un-namespace.h" 47 #include "libc_private.h" 48 #include "local.h" 49 50 static int sflush_locked(FILE *); 51 52 /* 53 * Flush a single file, or (if fp is NULL) all files. 54 * MT-safe version 55 */ 56 int 57 fflush(FILE *fp) 58 { 59 int retval; 60 61 if (fp == NULL) 62 return (_fwalk(sflush_locked)); 63 FLOCKFILE(fp); 64 if ((fp->_flags & (__SWR | __SRW)) == 0) { 65 errno = EBADF; 66 retval = EOF; 67 } else 68 retval = __sflush(fp); 69 FUNLOCKFILE(fp); 70 return (retval); 71 } 72 73 /* 74 * Flush a single file, or (if fp is NULL) all files. 75 * Non-MT-safe version 76 */ 77 int 78 __fflush(FILE *fp) 79 { 80 int retval; 81 82 if (fp == NULL) 83 return (_fwalk(sflush_locked)); 84 if ((fp->_flags & (__SWR | __SRW)) == 0) { 85 errno = EBADF; 86 retval = EOF; 87 } else 88 retval = __sflush(fp); 89 return (retval); 90 } 91 92 int 93 __sflush(FILE *fp) 94 { 95 unsigned char *p; 96 int n, t; 97 98 t = fp->_flags; 99 if ((t & __SWR) == 0) 100 return (0); 101 102 if ((p = fp->_bf._base) == NULL) 103 return (0); 104 105 n = fp->_p - p; /* write this much */ 106 107 /* 108 * Set these immediately to avoid problems with longjmp and to allow 109 * exchange buffering (via setvbuf) in user write function. 110 */ 111 fp->_p = p; 112 fp->_w = t & (__SLBF|__SNBF) ? 0 : fp->_bf._size; 113 114 for (; n > 0; n -= t, p += t) { 115 t = _swrite(fp, (char *)p, n); 116 if (t <= 0) { 117 fp->_flags |= __SERR; 118 return (EOF); 119 } 120 } 121 return (0); 122 } 123 124 static int 125 sflush_locked(FILE *fp) 126 { 127 int ret; 128 129 FLOCKFILE(fp); 130 ret = __sflush(fp); 131 FUNLOCKFILE(fp); 132 return (ret); 133 } 134