xref: /minix3/lib/libm/noieee_src/n_roundf.c (revision 2fe8fb192fe7e8720e3e7a77f928da545e872a6a)
1*2fe8fb19SBen Gras /*-
2*2fe8fb19SBen Gras  * Copyright (c) 2003, Steven G. Kargl
3*2fe8fb19SBen Gras  * All rights reserved.
4*2fe8fb19SBen Gras  *
5*2fe8fb19SBen Gras  * Redistribution and use in source and binary forms, with or without
6*2fe8fb19SBen Gras  * modification, are permitted provided that the following conditions
7*2fe8fb19SBen Gras  * are met:
8*2fe8fb19SBen Gras  * 1. Redistributions of source code must retain the above copyright
9*2fe8fb19SBen Gras  *    notice unmodified, this list of conditions, and the following
10*2fe8fb19SBen Gras  *    disclaimer.
11*2fe8fb19SBen Gras  * 2. Redistributions in binary form must reproduce the above copyright
12*2fe8fb19SBen Gras  *    notice, this list of conditions and the following disclaimer in the
13*2fe8fb19SBen Gras  *    documentation and/or other materials provided with the distribution.
14*2fe8fb19SBen Gras  *
15*2fe8fb19SBen Gras  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16*2fe8fb19SBen Gras  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17*2fe8fb19SBen Gras  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18*2fe8fb19SBen Gras  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19*2fe8fb19SBen Gras  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20*2fe8fb19SBen Gras  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21*2fe8fb19SBen Gras  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22*2fe8fb19SBen Gras  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23*2fe8fb19SBen Gras  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24*2fe8fb19SBen Gras  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25*2fe8fb19SBen Gras  */
26*2fe8fb19SBen Gras 
27*2fe8fb19SBen Gras #include <sys/cdefs.h>
28*2fe8fb19SBen Gras #if defined(LIBM_SCCS) && !defined(lint)
29*2fe8fb19SBen Gras __RCSID("$NetBSD: n_roundf.c,v 1.1 2006/01/17 13:16:08 is Exp $");
30*2fe8fb19SBen Gras #if 0
31*2fe8fb19SBen Gras __FBSDID("$FreeBSD: src/lib/msun/src/s_roundf.c,v 1.1 2004/06/07 08:05:36 das Exp $");
32*2fe8fb19SBen Gras #endif
33*2fe8fb19SBen Gras #endif
34*2fe8fb19SBen Gras 
35*2fe8fb19SBen Gras #include <math.h>
36*2fe8fb19SBen Gras 
37*2fe8fb19SBen Gras float
roundf(float x)38*2fe8fb19SBen Gras roundf(float x)
39*2fe8fb19SBen Gras {
40*2fe8fb19SBen Gras 	float t;
41*2fe8fb19SBen Gras 
42*2fe8fb19SBen Gras 	if (x >= 0.0) {
43*2fe8fb19SBen Gras 		t = ceilf(x);
44*2fe8fb19SBen Gras 		if (t - x > 0.5)
45*2fe8fb19SBen Gras 			t -= 1.0;
46*2fe8fb19SBen Gras 		return (t);
47*2fe8fb19SBen Gras 	} else {
48*2fe8fb19SBen Gras 		t = ceilf(-x);
49*2fe8fb19SBen Gras 		if (t + x > 0.5)
50*2fe8fb19SBen Gras 			t -= 1.0;
51*2fe8fb19SBen Gras 		return (-t);
52*2fe8fb19SBen Gras 	}
53*2fe8fb19SBen Gras }
54