snprintf/fflush.c

   1 /*      $OpenBSD: fflush.c,v 1.7 2009/10/22 01:23:16 guenther Exp $ */
   2 /*-
   3  * Copyright (c) 1990, 1993
   4  *      The Regents of the University of California.  All rights reserved.
   5  *
   6  * This code is derived from software contributed to Berkeley by
   7  * Chris Torek.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #include <errno.h>
  35 #include <stdio.h>
  36 #include "local.h"
  37
  38 /* Flush a single file, or (if fp is NULL) all files.  */
  39 int ust_safe_fflush(LFILE *fp)
  40 {
  41
  42         if (fp == NULL)
  43                 return 0;
  44 //              return (_fwalk(__sflush));
  45         if ((fp->_flags & (__SWR | __SRW)) == 0) {
  46                 errno = EBADF;
  47                 return (EOF);
  48         }
  49         return (__sflush(fp));
  50 }
  51
  52 int
  53 __sflush(LFILE *fp)
  54 {
  55         unsigned char *p;
  56         int n, t;
  57
  58         t = fp->_flags;
  59         if ((t & __SWR) == 0)
  60                 return (0);
  61
  62         if ((p = fp->_bf._base) == NULL)
  63                 return (0);
  64
  65         n = fp->_p - p;         /* write this much */
  66
  67         /*
  68          * Set these immediately to avoid problems with longjmp and to allow
  69          * exchange buffering (via setvbuf) in user write function.
  70          */
  71         fp->_p = p;
  72         fp->_w = t & (__SLBF|__SNBF) ? 0 : fp->_bf._size;
  73
  74         for (; n > 0; n -= t, p += t) {
  75                 t = (*fp->_write)(fp->_cookie, (char *)p, n);
  76                 if (t <= 0) {
  77                         fp->_flags |= __SERR;
  78                         return (EOF);
  79                 }
  80         }
  81         return (0);
  82 }