86 lines
2.5 KiB
C
86 lines
2.5 KiB
C
/* Copyright (C) 1991, 1993 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Library General Public License as
|
|
published by the Free Software Foundation; either version 2 of the
|
|
License, or (at your option) any later version.
|
|
|
|
The GNU C Library 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
|
|
Library General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Library General Public
|
|
License along with the GNU C Library; see the file COPYING.LIB. If
|
|
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
|
|
Cambridge, MA 02139, USA. */
|
|
|
|
#include <ansidecl.h>
|
|
#include <stddef.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
|
|
|
|
/* Make STREAM use the buffering method given in MODE.
|
|
If MODE indicates full or line buffering, use BUF,
|
|
a buffer of SIZE bytes; if BUF is NULL, malloc a buffer. */
|
|
int
|
|
DEFUN(setvbuf, (stream, buf, mode, size),
|
|
FILE *stream AND char *buf AND int mode AND size_t size)
|
|
{
|
|
if (!__validfp(stream))
|
|
{
|
|
errno = EINVAL;
|
|
return EOF;
|
|
}
|
|
|
|
/* The ANSI standard says setvbuf can only be called before any I/O is done,
|
|
but we allow it to replace an old buffer, flushing it first. */
|
|
if (stream->__buffer != NULL)
|
|
{
|
|
(void) fflush(stream);
|
|
/* Free the old buffer if it was malloc'd. */
|
|
if (!stream->__userbuf)
|
|
free(stream->__buffer);
|
|
}
|
|
|
|
stream->__get_limit = stream->__put_limit = NULL;
|
|
stream->__bufp = stream->__buffer = NULL;
|
|
stream->__userbuf = stream->__linebuf = stream->__linebuf_active = 0;
|
|
|
|
switch (mode)
|
|
{
|
|
default:
|
|
errno = EINVAL;
|
|
return EOF;
|
|
case _IONBF: /* Unbuffered. */
|
|
stream->__buffer = NULL;
|
|
stream->__bufsize = 0;
|
|
stream->__userbuf = 1;
|
|
break;
|
|
case _IOLBF: /* Line buffered. */
|
|
stream->__linebuf = 1;
|
|
case _IOFBF: /* Fully buffered. */
|
|
if (size == 0)
|
|
{
|
|
errno = EINVAL;
|
|
return EOF;
|
|
}
|
|
stream->__bufsize = size;
|
|
if (buf != NULL)
|
|
stream->__userbuf = 1;
|
|
else if ((buf = (char *) malloc(size)) == NULL)
|
|
return EOF;
|
|
stream->__buffer = buf;
|
|
break;
|
|
}
|
|
|
|
stream->__bufp = stream->__buffer;
|
|
stream->__get_limit = stream->__buffer;
|
|
/* The next output operation will prime the stream for writing. */
|
|
stream->__put_limit = stream->__buffer;
|
|
|
|
return 0;
|
|
}
|