xref: /titanic_51/usr/src/lib/libbc/libc/stdio/common/stdiom.h (revision 791a814c934fcd4deb13b26c1f116ff283272a0d)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*      Copyright (c) 1984 AT&T */
23 /*        All Rights Reserved   */
24 
25 #pragma ident	"%Z%%M%	%I%	%E% SMI"
26 
27 /* The following macros improve performance of the stdio by reducing the
28 	number of calls to _bufsync and _wrtchk.  _BUFSYNC has the same
29 	effect as _bufsync, and _WRTCHK has the same effect as _wrtchk,
30 	but often these functions have no effect, and in those cases the
31 	macros avoid the expense of calling the functions.  */
32 
33 #define _BUFSYNC(iop)	if ((iop->_base + iop->_bufsiz) - iop->_ptr <   \
34 				( iop->_cnt < 0 ? 0 : iop->_cnt ) )  \
35 					_bufsync(iop)
36 #define _WRTCHK(iop)	((((iop->_flag & (_IOWRT | _IOEOF)) != _IOWRT) \
37 				|| (iop->_base == NULL)  \
38 				|| (iop->_ptr == iop->_base && iop->_cnt == 0 \
39 					&& !(iop->_flag & (_IONBF | _IOLBF)))) \
40 			? _wrtchk(iop) : 0 )
41