setlinebuf.c

UNIX下SH的实现源码

/* setlinebuf.c - line-buffer a stdio stream. */

/* Copyright (C) 1997 Free Software Foundation, Inc.

   This file is part of GNU Bash, the Bourne Again SHell.

   Bash is free software; you can redistribute it and/or modify it under
   the terms of the GNU General Public License as published by the Free
   Software Foundation; either version 2, or (at your option) any later
   version.

   Bash is distributed in the hope that it will be useful, but WITHOUT ANY
   WARRANTY; without even the implied warranty of MERCHANTABILITY or
   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   for more details.

   You should have received a copy of the GNU General Public License along
   with Bash; see the file COPYING.  If not, write to the Free Software
   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA */

#include <config.h>

#include <stdio.h>

extern char *xmalloc();

#if defined (USING_BASH_MALLOC)
#  define LBUF_BUFSIZE	1008
#else
#  define LBUF_BUFSIZE	BUFSIZ
#endif

/* Cause STREAM to buffer lines as opposed to characters or blocks. */
int
sh_setlinebuf (stream)
     FILE *stream;
{
  char *local_linebuf;

#if !defined (HAVE_SETLINEBUF) && !defined (HAVE_SETVBUF)
  return (0);
#endif

#if defined (USING_BASH_MALLOC)
  local_linebuf = xmalloc (LBUF_BUFSIZE);
#else
  local_linebuf = (char *)NULL;
#endif

#if defined (HAVE_SETVBUF)

#  if defined (SETVBUF_REVERSED)
  return (setvbuf (stream, _IOLBF, local_linebuf, LBUF_BUFSIZE));
#  else /* !SETVBUF_REVERSED */
  return (setvbuf (stream, local_linebuf, _IOLBF, LBUF_BUFSIZE));
#  endif /* !SETVBUF_REVERSED */
# else /* !HAVE_SETVBUF */

  setlinebuf (stream));
  return (0);

#endif /* !HAVE_SETVBUF */
}