golden hour

/usr/include/c++/4.8.2/tr1

File/Folder	Size	Actions
array	6.8 KB
bessel_function.tcc	21.6 KB
beta_function.tcc	5.47 KB
ccomplex	1.23 KB
cctype	1.38 KB
cfenv	1.96 KB
cfloat	1.35 KB
cinttypes	2.2 KB
climits	1.42 KB
cmath	36.55 KB
complex	12.04 KB
complex.h	1.23 KB
cstdarg	1.22 KB
cstdbool	1.31 KB
cstdint	2.56 KB
cstdio	1.44 KB
cstdlib	1.74 KB
ctgmath	1.22 KB
ctime	1.21 KB
ctype.h	1.18 KB
cwchar	1.67 KB
cwctype	1.42 KB
ell_integral.tcc	26.85 KB
exp_integral.tcc	15.41 KB
fenv.h	1.18 KB
float.h	1.18 KB
functional	69.15 KB
functional_hash.h	5.7 KB
gamma.tcc	13.97 KB
hashtable.h	40.56 KB
hashtable_policy.h	24.64 KB
hypergeometric.tcc	27.07 KB
inttypes.h	1.24 KB
legendre_function.tcc	10.32 KB
limits.h	1.19 KB
math.h	4.45 KB
memory	1.75 KB
modified_bessel_func.tcc	15.35 KB
poly_hermite.tcc	3.61 KB
poly_laguerre.tcc	11.08 KB
random	1.55 KB
random.h	71.48 KB
random.tcc	52.73 KB
regex	90.77 KB
riemann_zeta.tcc	13.34 KB
shared_ptr.h	31.91 KB
special_function_util.h	4.71 KB
stdarg.h	1.19 KB
stdbool.h	1.19 KB
stdint.h	1.19 KB
stdio.h	1.18 KB
stdlib.h	1.45 KB
tgmath.h	1.23 KB
tuple	11.83 KB
type_traits	18.57 KB
unordered_map	1.54 KB
unordered_map.h	9.98 KB
unordered_set	1.54 KB
unordered_set.h	9.32 KB
utility	3.15 KB
wchar.h	1.22 KB
wctype.h	1.23 KB

Edit: functional_hash.h

// TR1 functional_hash.h header -*- C++ -*-

// Copyright (C) 2007-2013 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library.  This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.

// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.

// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
// <http://www.gnu.org/licenses/>.

/** @file tr1/functional_hash.h
 *  This is an internal header file, included by other library headers.
 *  Do not attempt to use it directly. @headername{tr1/functional}
 */

#ifndef _GLIBCXX_TR1_FUNCTIONAL_HASH_H
#define _GLIBCXX_TR1_FUNCTIONAL_HASH_H 1

#pragma GCC system_header

namespace std _GLIBCXX_VISIBILITY(default)
{
namespace tr1
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION

/// Class template hash.
  // Declaration of default hash functor std::tr1::hash.  The types for
  // which std::tr1::hash<T> is well-defined is in clause 6.3.3. of the PDTR.
  template<typename _Tp>
    struct hash : public std::unary_function<_Tp, size_t>
    {
      size_t
      operator()(_Tp __val) const;
    };

/// Partial specializations for pointer types.
  template<typename _Tp>
    struct hash<_Tp*> : public std::unary_function<_Tp*, size_t>
    {
      size_t
      operator()(_Tp* __p) const
      { return reinterpret_cast<size_t>(__p); }
    };

/// Explicit specializations for integer types.
#define _TR1_hashtable_define_trivial_hash(_Tp) 	\
  template<>						\
    inline size_t					\
    hash<_Tp>::operator()(_Tp __val) const		\
    { return static_cast<size_t>(__val); }

_TR1_hashtable_define_trivial_hash(bool);
  _TR1_hashtable_define_trivial_hash(char);
  _TR1_hashtable_define_trivial_hash(signed char);
  _TR1_hashtable_define_trivial_hash(unsigned char);
  _TR1_hashtable_define_trivial_hash(wchar_t);
  _TR1_hashtable_define_trivial_hash(short);
  _TR1_hashtable_define_trivial_hash(int);
  _TR1_hashtable_define_trivial_hash(long);
  _TR1_hashtable_define_trivial_hash(long long);
  _TR1_hashtable_define_trivial_hash(unsigned short);
  _TR1_hashtable_define_trivial_hash(unsigned int);
  _TR1_hashtable_define_trivial_hash(unsigned long);
  _TR1_hashtable_define_trivial_hash(unsigned long long);

#undef _TR1_hashtable_define_trivial_hash

// Fowler / Noll / Vo (FNV) Hash (type FNV-1a)
  // (Used by the next specializations of std::tr1::hash.)

/// Dummy generic implementation (for sizeof(size_t) != 4, 8).
  template<size_t>
    struct _Fnv_hash_base
    {
      template<typename _Tp>
        static size_t
        hash(const _Tp* __ptr, size_t __clength)
        {
	  size_t __result = 0;
	  const char* __cptr = reinterpret_cast<const char*>(__ptr);
	  for (; __clength; --__clength)
	    __result = (__result * 131) + *__cptr++;
	  return __result;
	}
    };

template<>
    struct _Fnv_hash_base<4>
    {
      template<typename _Tp>
        static size_t
        hash(const _Tp* __ptr, size_t __clength)
        {
	  size_t __result = static_cast<size_t>(2166136261UL);
	  const char* __cptr = reinterpret_cast<const char*>(__ptr);
	  for (; __clength; --__clength)
	    {
	      __result ^= static_cast<size_t>(*__cptr++);
	      __result *= static_cast<size_t>(16777619UL);
	    }
	  return __result;
	}
    };
  
  template<>
    struct _Fnv_hash_base<8>
    {
      template<typename _Tp>
        static size_t
        hash(const _Tp* __ptr, size_t __clength)
        {
	  size_t __result
	    = static_cast<size_t>(14695981039346656037ULL);
	  const char* __cptr = reinterpret_cast<const char*>(__ptr);
	  for (; __clength; --__clength)
	    {
	      __result ^= static_cast<size_t>(*__cptr++);
	      __result *= static_cast<size_t>(1099511628211ULL);
	    }
	  return __result;
	}
    };

struct _Fnv_hash
  : public _Fnv_hash_base<sizeof(size_t)>
  {
    using _Fnv_hash_base<sizeof(size_t)>::hash;

template<typename _Tp>
      static size_t
      hash(const _Tp& __val)
      { return hash(&__val, sizeof(__val)); }
  };

/// Explicit specializations for float.
  template<>
    inline size_t
    hash<float>::operator()(float __val) const
    {
      // 0 and -0 both hash to zero.
      return __val != 0.0f ? std::tr1::_Fnv_hash::hash(__val) : 0;
    }

/// Explicit specializations for double.
  template<>
    inline size_t
    hash<double>::operator()(double __val) const
    {
      // 0 and -0 both hash to zero.
      return __val != 0.0 ? std::tr1::_Fnv_hash::hash(__val) : 0;
    }

/// Explicit specializations for long double.
  template<>
    _GLIBCXX_PURE size_t
    hash<long double>::operator()(long double __val) const;

/// Explicit specialization of member operator for non-builtin types.
  template<>
    _GLIBCXX_PURE size_t
    hash<string>::operator()(string) const;

template<>
    _GLIBCXX_PURE size_t
    hash<const string&>::operator()(const string&) const;

#ifdef _GLIBCXX_USE_WCHAR_T
  template<>
    _GLIBCXX_PURE size_t
    hash<wstring>::operator()(wstring) const;

template<>
    _GLIBCXX_PURE size_t
    hash<const wstring&>::operator()(const wstring&) const;
#endif

_GLIBCXX_END_NAMESPACE_VERSION
}
}

#endif // _GLIBCXX_TR1_FUNCTIONAL_HASH_H