1/* Return arc hyperbole sine for long double value.
2   Copyright (C) 1997, 1998 Free Software Foundation, Inc.
3   This file is part of the GNU C Library.
4   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
5
6   The GNU C Library is free software; you can redistribute it and/or
7   modify it under the terms of the GNU Lesser General Public
8   License as published by the Free Software Foundation; either
9   version 2.1 of the License, or (at your option) any later version.
10
11   The GNU C Library is distributed in the hope that it will be useful,
12   but WITHOUT ANY WARRANTY; without even the implied warranty of
13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14   Lesser General Public License for more details.
15
16   You should have received a copy of the GNU Lesser General Public
17   License along with the GNU C Library; if not, write to the Free
18   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
19   02111-1307 USA.  */
20
21#include <complex.h>
22#include <math.h>
23
24
25__complex__ long double
26__casinhl (__complex__ long double x)
27{
28  __complex__ long double res;
29  int rcls = fpclassify (__real__ x);
30  int icls = fpclassify (__imag__ x);
31
32  if (rcls <= FP_INFINITE || icls <= FP_INFINITE)
33    {
34      if (icls == FP_INFINITE)
35	{
36	  __real__ res = copysignl (HUGE_VALL, __real__ x);
37
38	  if (rcls == FP_NAN)
39	    __imag__ res = nanl ("");
40	  else
41	    __imag__ res = copysignl (rcls >= FP_ZERO ? M_PI_2l : M_PI_4l,
42					__imag__ x);
43	}
44      else if (rcls <= FP_INFINITE)
45	{
46	  __real__ res = __real__ x;
47	  if ((rcls == FP_INFINITE && icls >= FP_ZERO)
48	      || (rcls == FP_NAN && icls == FP_ZERO))
49	    __imag__ res = copysignl (0.0, __imag__ x);
50	  else
51	    __imag__ res = nanl ("");
52	}
53      else
54	{
55	  __real__ res = nanl ("");
56	  __imag__ res = nanl ("");
57	}
58    }
59  else if (rcls == FP_ZERO && icls == FP_ZERO)
60    {
61      res = x;
62    }
63  else
64    {
65      __complex__ long double y;
66
67      __real__ y = (__real__ x - __imag__ x) * (__real__ x + __imag__ x) + 1.0;
68      __imag__ y = 2.0 * __real__ x * __imag__ x;
69
70      y = __csqrtl (y);
71
72      __real__ y += __real__ x;
73      __imag__ y += __imag__ x;
74
75      res = __clogl (y);
76    }
77
78  return res;
79}
80weak_alias (__casinhl, casinhl)
81