1/* Return arc hyperbolic cosine for a complex type.
2   Copyright (C) 1997-2018 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, see
18   <http://www.gnu.org/licenses/>.  */
19
20#include "quadmath-imp.h"
21
22__complex128
23cacoshq (__complex128 x)
24{
25  __complex128 res;
26  int rcls = fpclassifyq (__real__ x);
27  int icls = fpclassifyq (__imag__ x);
28
29  if (rcls <= QUADFP_INFINITE || icls <= QUADFP_INFINITE)
30    {
31      if (icls == QUADFP_INFINITE)
32	{
33	  __real__ res = HUGE_VALQ;
34
35	  if (rcls == QUADFP_NAN)
36	    __imag__ res = nanq ("");
37	  else
38	    __imag__ res = copysignq ((rcls == QUADFP_INFINITE
39					? (__real__ x < 0
40					   ? M_PIq - M_PI_4q
41					   : M_PI_4q)
42					: M_PI_2q), __imag__ x);
43	}
44      else if (rcls == QUADFP_INFINITE)
45	{
46	  __real__ res = HUGE_VALQ;
47
48	  if (icls >= QUADFP_ZERO)
49	    __imag__ res = copysignq (signbitq (__real__ x)
50				       ? M_PIq : 0, __imag__ x);
51	  else
52	    __imag__ res = nanq ("");
53	}
54      else
55	{
56	  __real__ res = nanq ("");
57	  if (rcls == QUADFP_ZERO)
58	    __imag__ res = M_PI_2q;
59	  else
60	    __imag__ res = nanq ("");
61	}
62    }
63  else if (rcls == QUADFP_ZERO && icls == QUADFP_ZERO)
64    {
65      __real__ res = 0;
66      __imag__ res = copysignq (M_PI_2q, __imag__ x);
67    }
68  else
69    {
70      __complex128 y;
71
72      __real__ y = -__imag__ x;
73      __imag__ y = __real__ x;
74
75      y = __quadmath_kernel_casinhq (y, 1);
76
77      if (signbitq (__imag__ x))
78	{
79	  __real__ res = __real__ y;
80	  __imag__ res = -__imag__ y;
81	}
82      else
83	{
84	  __real__ res = -__real__ y;
85	  __imag__ res = __imag__ y;
86	}
87    }
88
89  return res;
90}
91