xref: /titanic_41/usr/src/cmd/sendmail/libsm/fpurge.c (revision 7c478bd95313f5f23a4c958a745db2134aa03244)
1*7c478bd9Sstevel@tonic-gate /*
2*7c478bd9Sstevel@tonic-gate  * Copyright (c) 2000-2001 Sendmail, Inc. and its suppliers.
3*7c478bd9Sstevel@tonic-gate  *      All rights reserved.
4*7c478bd9Sstevel@tonic-gate  * Copyright (c) 1990, 1993
5*7c478bd9Sstevel@tonic-gate  *	The Regents of the University of California.  All rights reserved.
6*7c478bd9Sstevel@tonic-gate  *
7*7c478bd9Sstevel@tonic-gate  * This code is derived from software contributed to Berkeley by
8*7c478bd9Sstevel@tonic-gate  * Chris Torek.
9*7c478bd9Sstevel@tonic-gate  *
10*7c478bd9Sstevel@tonic-gate  * By using this file, you agree to the terms and conditions set
11*7c478bd9Sstevel@tonic-gate  * forth in the LICENSE file which can be found at the top level of
12*7c478bd9Sstevel@tonic-gate  * the sendmail distribution.
13*7c478bd9Sstevel@tonic-gate  */
14*7c478bd9Sstevel@tonic-gate 
15*7c478bd9Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
16*7c478bd9Sstevel@tonic-gate 
17*7c478bd9Sstevel@tonic-gate #include <sm/gen.h>
18*7c478bd9Sstevel@tonic-gate SM_RCSID("@(#)$Id: fpurge.c,v 1.18 2001/01/28 00:29:35 ca Exp $")
19*7c478bd9Sstevel@tonic-gate #include <stdlib.h>
20*7c478bd9Sstevel@tonic-gate #include <errno.h>
21*7c478bd9Sstevel@tonic-gate #include <sm/io.h>
22*7c478bd9Sstevel@tonic-gate #include <sm/assert.h>
23*7c478bd9Sstevel@tonic-gate #include "local.h"
24*7c478bd9Sstevel@tonic-gate 
25*7c478bd9Sstevel@tonic-gate /*
26*7c478bd9Sstevel@tonic-gate **  SM_IO_PURGE -- purge/empty the buffer without committing buffer content
27*7c478bd9Sstevel@tonic-gate **
28*7c478bd9Sstevel@tonic-gate **	Parameters:
29*7c478bd9Sstevel@tonic-gate **		fp -- file pointer to purge
30*7c478bd9Sstevel@tonic-gate **
31*7c478bd9Sstevel@tonic-gate **	Returns:
32*7c478bd9Sstevel@tonic-gate **		Failure: returns SM_IO_EOF and sets errno
33*7c478bd9Sstevel@tonic-gate **		Success: returns 0 (zero)
34*7c478bd9Sstevel@tonic-gate */
35*7c478bd9Sstevel@tonic-gate 
36*7c478bd9Sstevel@tonic-gate int
37*7c478bd9Sstevel@tonic-gate sm_io_purge(fp)
38*7c478bd9Sstevel@tonic-gate 	register SM_FILE_T *fp;
39*7c478bd9Sstevel@tonic-gate {
40*7c478bd9Sstevel@tonic-gate 	SM_REQUIRE_ISA(fp, SmFileMagic);
41*7c478bd9Sstevel@tonic-gate 	if (!fp->f_flags)
42*7c478bd9Sstevel@tonic-gate 	{
43*7c478bd9Sstevel@tonic-gate 		errno = EBADF;
44*7c478bd9Sstevel@tonic-gate 		return SM_IO_EOF;
45*7c478bd9Sstevel@tonic-gate 	}
46*7c478bd9Sstevel@tonic-gate 
47*7c478bd9Sstevel@tonic-gate 	if (HASUB(fp))
48*7c478bd9Sstevel@tonic-gate 		FREEUB(fp);
49*7c478bd9Sstevel@tonic-gate 	fp->f_p = fp->f_bf.smb_base;
50*7c478bd9Sstevel@tonic-gate 	fp->f_r = 0;
51*7c478bd9Sstevel@tonic-gate 
52*7c478bd9Sstevel@tonic-gate 	/* implies SMFBF */
53*7c478bd9Sstevel@tonic-gate 	fp->f_w = fp->f_flags & (SMLBF|SMNBF) ? 0 : fp->f_bf.smb_size;
54*7c478bd9Sstevel@tonic-gate 	return 0;
55*7c478bd9Sstevel@tonic-gate }
56