1/*
2 * Copyright (c) 2000-2001 Sendmail, Inc. and its suppliers.
3 *      All rights reserved.
4 * Copyright (c) 1990, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Chris Torek.
9 *
10 * By using this file, you agree to the terms and conditions set
11 * forth in the LICENSE file which can be found at the top level of
12 * the sendmail distribution.
13 */
14
15#pragma ident	"%Z%%M%	%I%	%E% SMI"
16
17#include <sm/gen.h>
18SM_RCSID("@(#)$Id: fpurge.c,v 1.18 2001/01/28 00:29:35 ca Exp $")
19#include <stdlib.h>
20#include <errno.h>
21#include <sm/io.h>
22#include <sm/assert.h>
23#include "local.h"
24
25/*
26**  SM_IO_PURGE -- purge/empty the buffer without committing buffer content
27**
28**	Parameters:
29**		fp -- file pointer to purge
30**
31**	Returns:
32**		Failure: returns SM_IO_EOF and sets errno
33**		Success: returns 0 (zero)
34*/
35
36int
37sm_io_purge(fp)
38	register SM_FILE_T *fp;
39{
40	SM_REQUIRE_ISA(fp, SmFileMagic);
41	if (!fp->f_flags)
42	{
43		errno = EBADF;
44		return SM_IO_EOF;
45	}
46
47	if (HASUB(fp))
48		FREEUB(fp);
49	fp->f_p = fp->f_bf.smb_base;
50	fp->f_r = 0;
51
52	/* implies SMFBF */
53	fp->f_w = fp->f_flags & (SMLBF|SMNBF) ? 0 : fp->f_bf.smb_size;
54	return 0;
55}
56