snprintf/fflush.c

   1 /*      $OpenBSD: fflush.c,v 1.7 2009/10/22 01:23:16 guenther Exp $ */
   2 /*
   3  * SPDX-License-Identifier: BSD-3-Clause
   4  *
   5  * Copyright (C) 1990, 1993
   6  *      The Regents of the University of California.  All rights reserved.
   7  *
   8  * This code is derived from software contributed to Berkeley by
   9  * Chris Torek.
  10  */
  11
  12 #include <errno.h>
  13 #include <stdio.h>
  14 #include "local.h"
  15
  16 /* Flush a single file, or (if fp is NULL) all files.  */
  17 int ust_safe_fflush(LTTNG_UST_LFILE *fp)
  18 {
  19
  20         if (fp == NULL)
  21                 return 0;
  22 //              return (_fwalk(__sflush));
  23         if ((fp->_flags & (__SWR | __SRW)) == 0) {
  24                 errno = EBADF;
  25                 return (EOF);
  26         }
  27         return (__sflush(fp));
  28 }
  29
  30 int
  31 __sflush(LTTNG_UST_LFILE *fp)
  32 {
  33         unsigned char *p;
  34         int n, t;
  35
  36         t = fp->_flags;
  37         if ((t & __SWR) == 0)
  38                 return (0);
  39
  40         if ((p = fp->_bf._base) == NULL)
  41                 return (0);
  42
  43         n = fp->_p - p;         /* write this much */
  44
  45         /*
  46          * Set these immediately to avoid problems with longjmp and to allow
  47          * exchange buffering (via setvbuf) in user write function.
  48          */
  49         fp->_p = p;
  50         fp->_w = t & (__SLBF|__SNBF) ? 0 : fp->_bf._size;
  51
  52         for (; n > 0; n -= t, p += t) {
  53                 t = (*fp->_write)(fp->_cookie, (char *)p, n);
  54                 if (t <= 0) {
  55                         fp->_flags |= __SERR;
  56                         return (EOF);
  57                 }
  58         }
  59         return (0);
  60 }