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 (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22/*
23 * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
24 */
25/*
26 * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
27 * Use is subject to license terms.
28 */
29
30#pragma weak __csin = csin
31
32/* INDENT OFF */
33/*
34 * dcomplex csin(dcomplex z);
35 *
36 * If z = x+iy, then since csin(iz) = i*csinh(z),  we have
37 *
38 * csin(z)	= csin((-1)*(-z)) = csin(i*i*(-z))
39 *		= i*csinh(i*(-z)) = i*csinh(i*(-x-yi))
40 *		= i*csinh(y-ix)
41 *		= -Im(csinh(y-ix))+i*Re(csinh(y-ix))
42 */
43/* INDENT ON */
44
45#include "libm.h"
46#include "complex_wrapper.h"
47
48dcomplex
49csin(dcomplex z) {
50	double x, y;
51	dcomplex ans, ct;
52
53	x = D_RE(z);
54	y = D_IM(z);
55	D_RE(z) = y;
56	D_IM(z) = -x;
57	ct = csinh(z);
58	D_RE(ans) = -D_IM(ct);
59	D_IM(ans) = D_RE(ct);
60	return (ans);
61}
62