1/* Complex cosine hyperbole function for double.
2   Copyright (C) 1997 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 <fenv.h>
23#include <math.h>
24
25#include "math_private.h"
26
27
28__complex__ double
29__ccosh (__complex__ double x)
30{
31  __complex__ double retval;
32  int rcls = fpclassify (__real__ x);
33  int icls = fpclassify (__imag__ x);
34
35  if (rcls >= FP_ZERO)
36    {
37      /* Real part is finite.  */
38      if (icls >= FP_ZERO)
39	{
40	  /* Imaginary part is finite.  */
41	  double sinh_val = sinh (__real__ x);
42	  double cosh_val = cosh (__real__ x);
43	  double sinix, cosix;
44
45	  sincos (__imag__ x, &sinix, &cosix);
46
47	  __real__ retval = cosh_val * cosix;
48	  __imag__ retval = sinh_val * sinix;
49	}
50      else
51	{
52	  __imag__ retval = __real__ x == 0.0 ? 0.0 : nan ("");
53	  __real__ retval = nan ("") + nan ("");
54
55#ifdef FE_INVALID
56	  if (icls == FP_INFINITE)
57	    feraiseexcept (FE_INVALID);
58#endif
59	}
60    }
61  else if (rcls == FP_INFINITE)
62    {
63      /* Real part is infinite.  */
64      if (icls == FP_ZERO)
65	{
66	  /* Imaginary part is 0.0.  */
67	  __real__ retval = HUGE_VAL;
68	  __imag__ retval = __imag__ x * copysign (1.0, __real__ x);
69	}
70      else if (icls > FP_ZERO)
71	{
72	  /* Imaginary part is finite.  */
73	  double sinix, cosix;
74
75	  sincos (__imag__ x, &sinix, &cosix);
76
77	  __real__ retval = copysign (HUGE_VAL, cosix);
78	  __imag__ retval = (copysign (HUGE_VAL, sinix)
79			     * copysign (1.0, __real__ x));
80	}
81      else
82	{
83	  /* The addition raises the invalid exception.  */
84	  __real__ retval = HUGE_VAL;
85	  __imag__ retval = nan ("") + nan ("");
86
87#ifdef FE_INVALID
88	  if (icls == FP_INFINITE)
89	    feraiseexcept (FE_INVALID);
90#endif
91	}
92    }
93  else
94    {
95      __real__ retval = nan ("");
96      __imag__ retval = __imag__ x == 0.0 ? __imag__ x : nan ("");
97    }
98
99  return retval;
100}
101weak_alias (__ccosh, ccosh)
102#ifdef NO_LONG_DOUBLE
103strong_alias (__ccosh, __ccoshl)
104weak_alias (__ccosh, ccoshl)
105#endif
106