xref: /titanic_41/usr/src/lib/libast/common/stdio/fwide.c (revision 0bb073995ac5a95bd35f2dd790df1ea3d8c2d507)
1 /***********************************************************************
2 *                                                                      *
3 *               This software is part of the ast package               *
4 *           Copyright (c) 1985-2007 AT&T Knowledge Ventures            *
5 *                      and is licensed under the                       *
6 *                  Common Public License, Version 1.0                  *
7 *                      by AT&T Knowledge Ventures                      *
8 *                                                                      *
9 *                A copy of the License is available at                 *
10 *            http://www.opensource.org/licenses/cpl1.0.txt             *
11 *         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
12 *                                                                      *
13 *              Information and Software Systems Research               *
14 *                            AT&T Research                             *
15 *                           Florham Park NJ                            *
16 *                                                                      *
17 *                 Glenn Fowler <gsf@research.att.com>                  *
18 *                  David Korn <dgk@research.att.com>                   *
19 *                   Phong Vo <kpv@research.att.com>                    *
20 *                                                                      *
21 ***********************************************************************/
22 #pragma prototyped
23 
24 #include "stdhdr.h"
25 
26 int
27 fwide(Sfio_t* f, int mode)
28 {
29 	STDIO_INT(f, "fwide", int, (Sfio_t*, int), (f, mode))
30 
31 	if (mode > 0)
32 	{
33 		f->bits &= ~SF_MB;
34 		f->bits |= SF_WC;
35 	}
36 	else if (mode < 0)
37 	{
38 		f->bits &= ~SF_WC;
39 		f->bits |= SF_MB;
40 	}
41 	if (f->bits & SF_MB)
42 		return -1;
43 	if (f->bits & SF_WC)
44 		return 1;
45 	if ((f->flags & SF_SYNCED) || f->next > f->data)
46 	{
47 		f->bits |= SF_MB;
48 		return -1;
49 	}
50 	return 0;
51 }
52