_string_hash.h

Go to the documentation of this file.

/*
 * Copyright (c) 1997-1999
 * Silicon Graphics Computer Systems, Inc.
 *
 * Copyright (c) 1999
 * Boris Fomitchev
 *
 * This material is provided "as is", with absolutely no warranty expressed
 * or implied. Any use is at your own risk.
 *
 * Permission to use or copy this software for any purpose is hereby granted
 * without fee, provided the above notices are retained on all copies.
 * Permission to modify the code and to distribute modified code is granted,
 * provided the above notices are retained, and a notice that the code was
 * modified is included with the above copyright notice.
 *
 */
 
#ifndef _STLP_STRING_HASH_H
#define _STLP_STRING_HASH_H
 
#ifndef _STLP_HASH_FUN_H
# include <stl/_hash_fun.h>
#endif
 
#ifndef _STLP_INTERNAL_STRING_H
# include <stl/_string.h>
#endif
 
_STLP_BEGIN_NAMESPACE
 
template <class _CharT, class _Traits, class _Alloc>
_STLP_INLINE_LOOP size_t
__stl_string_hash(const basic_string<_CharT,_Traits,_Alloc>& __s) {
  unsigned long __h = 0;
  size_t __len = __s.size();
  const _CharT* __data = __s.data();
  for ( size_t __i = 0; __i < __len; ++__i)
    __h = /* 5 *__h */(__h << 2) + __h + __data[__i];
  return size_t(__h);
}
 
#if defined (_STLP_CLASS_PARTIAL_SPECIALIZATION) && \
  (!defined(__BORLANDC__) || (__BORLANDC__ >= 0x560))
template <class _CharT, class _Traits, class _Alloc>
struct hash<basic_string<_CharT,_Traits,_Alloc> > {
  size_t operator()(const basic_string<_CharT,_Traits,_Alloc>& __s) const
    { return __stl_string_hash(__s); }
};
 
#else
 
_STLP_TEMPLATE_NULL
struct _STLP_CLASS_DECLSPEC hash<string> {
  size_t operator()(const string& __s) const
    { return __stl_string_hash(__s); }
};
 
#  if defined (_STLP_HAS_WCHAR_T)
_STLP_TEMPLATE_NULL
struct _STLP_CLASS_DECLSPEC hash<wstring> {
  size_t operator()(const wstring& __s) const
    { return __stl_string_hash(__s); }
};
#  endif
 
#endif /* _STLP_CLASS_PARTIAL_SPECIALIZATION */
 
_STLP_END_NAMESPACE
 
#endif