1
2// Copyright 2005-2014 Daniel James.
3// Distributed under the Boost Software License, Version 1.0. (See accompanying
4// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
5
6// Based on Peter Dimov's proposal
7// http://www.open-std.org/JTC1/SC22/WG21/docs/papers/2005/n1756.pdf
8// issue 6.18.
9//
10// This also contains public domain code from MurmurHash. From the
11// MurmurHash header:
12
13// MurmurHash3 was written by Austin Appleby, and is placed in the public
14// domain. The author hereby disclaims copyright to this source code.
15
16#if !defined(BOOST_FUNCTIONAL_HASH_HASH_HPP)
17#define BOOST_FUNCTIONAL_HASH_HASH_HPP
18
19#include <boost/functional/hash/hash_fwd.hpp>
20#include <functional>
21#include <boost/functional/hash/detail/hash_float.hpp>
22#include <string>
23#include <boost/limits.hpp>
24#include <boost/type_traits/is_enum.hpp>
25#include <boost/type_traits/is_integral.hpp>
26#include <boost/utility/enable_if.hpp>
27#include <boost/cstdint.hpp>
28
29#if defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
30#include <boost/type_traits/is_pointer.hpp>
31#endif
32
33#if !defined(BOOST_NO_CXX11_HDR_TYPEINDEX)
34#include <typeindex>
35#endif
36
37#if defined(BOOST_MSVC)
38#pragma warning(push)
39
40#if BOOST_MSVC >= 1400
41#pragma warning(disable:6295) // Ill-defined for-loop : 'unsigned int' values
42 // are always of range '0' to '4294967295'.
43 // Loop executes infinitely.
44#endif
45
46#endif
47
48#if BOOST_WORKAROUND(__GNUC__, < 3) \
49 && !defined(__SGI_STL_PORT) && !defined(_STLPORT_VERSION)
50#define BOOST_HASH_CHAR_TRAITS string_char_traits
51#else
52#define BOOST_HASH_CHAR_TRAITS char_traits
53#endif
54
55#if defined(_MSC_VER)
56# define BOOST_FUNCTIONAL_HASH_ROTL32(x, r) _rotl(x,r)
57#else
58# define BOOST_FUNCTIONAL_HASH_ROTL32(x, r) (x << r) | (x >> (32 - r))
59#endif
60
61namespace boost
62{
63 namespace hash_detail
64 {
65 struct enable_hash_value { typedef std::size_t type; };
66
67 template <typename T> struct basic_numbers {};
68 template <typename T> struct long_numbers;
69 template <typename T> struct ulong_numbers;
70 template <typename T> struct float_numbers {};
71
72 template <> struct basic_numbers<bool> :
73 boost::hash_detail::enable_hash_value {};
74 template <> struct basic_numbers<char> :
75 boost::hash_detail::enable_hash_value {};
76 template <> struct basic_numbers<unsigned char> :
77 boost::hash_detail::enable_hash_value {};
78 template <> struct basic_numbers<signed char> :
79 boost::hash_detail::enable_hash_value {};
80 template <> struct basic_numbers<short> :
81 boost::hash_detail::enable_hash_value {};
82 template <> struct basic_numbers<unsigned short> :
83 boost::hash_detail::enable_hash_value {};
84 template <> struct basic_numbers<int> :
85 boost::hash_detail::enable_hash_value {};
86 template <> struct basic_numbers<unsigned int> :
87 boost::hash_detail::enable_hash_value {};
88 template <> struct basic_numbers<long> :
89 boost::hash_detail::enable_hash_value {};
90 template <> struct basic_numbers<unsigned long> :
91 boost::hash_detail::enable_hash_value {};
92
93#if !defined(BOOST_NO_INTRINSIC_WCHAR_T)
94 template <> struct basic_numbers<wchar_t> :
95 boost::hash_detail::enable_hash_value {};
96#endif
97
98 // long_numbers is defined like this to allow for separate
99 // specialization for long_long and int128_type, in case
100 // they conflict.
101 template <typename T> struct long_numbers2 {};
102 template <typename T> struct ulong_numbers2 {};
103 template <typename T> struct long_numbers : long_numbers2<T> {};
104 template <typename T> struct ulong_numbers : ulong_numbers2<T> {};
105
106#if !defined(BOOST_NO_LONG_LONG)
107 template <> struct long_numbers<boost::long_long_type> :
108 boost::hash_detail::enable_hash_value {};
109 template <> struct ulong_numbers<boost::ulong_long_type> :
110 boost::hash_detail::enable_hash_value {};
111#endif
112
113#if defined(BOOST_HAS_INT128)
114 template <> struct long_numbers2<boost::int128_type> :
115 boost::hash_detail::enable_hash_value {};
116 template <> struct ulong_numbers2<boost::uint128_type> :
117 boost::hash_detail::enable_hash_value {};
118#endif
119
120 template <> struct float_numbers<float> :
121 boost::hash_detail::enable_hash_value {};
122 template <> struct float_numbers<double> :
123 boost::hash_detail::enable_hash_value {};
124 template <> struct float_numbers<long double> :
125 boost::hash_detail::enable_hash_value {};
126 }
127
128 template <typename T>
129 typename boost::hash_detail::basic_numbers<T>::type hash_value(T);
130 template <typename T>
131 typename boost::hash_detail::long_numbers<T>::type hash_value(T);
132 template <typename T>
133 typename boost::hash_detail::ulong_numbers<T>::type hash_value(T);
134
135 template <typename T>
136 typename boost::enable_if<boost::is_enum<T>, std::size_t>::type
137 hash_value(T);
138
139#if !BOOST_WORKAROUND(__DMC__, <= 0x848)
140 template <class T> std::size_t hash_value(T* const&);
141#else
142 template <class T> std::size_t hash_value(T*);
143#endif
144
145#if !defined(BOOST_NO_FUNCTION_TEMPLATE_ORDERING)
146 template< class T, unsigned N >
147 std::size_t hash_value(const T (&x)[N]);
148
149 template< class T, unsigned N >
150 std::size_t hash_value(T (&x)[N]);
151#endif
152
153 template <class Ch, class A>
154 std::size_t hash_value(
155 std::basic_string<Ch, std::BOOST_HASH_CHAR_TRAITS<Ch>, A> const&);
156
157 template <typename T>
158 typename boost::hash_detail::float_numbers<T>::type hash_value(T);
159
160#if !defined(BOOST_NO_CXX11_HDR_TYPEINDEX)
161 std::size_t hash_value(std::type_index);
162#endif
163
164 // Implementation
165
166 namespace hash_detail
167 {
168 template <class T>
169 inline std::size_t hash_value_signed(T val)
170 {
171 const int size_t_bits = std::numeric_limits<std::size_t>::digits;
172 // ceiling(std::numeric_limits<T>::digits / size_t_bits) - 1
173 const int length = (std::numeric_limits<T>::digits - 1)
174 / size_t_bits;
175
176 std::size_t seed = 0;
177 T positive = val < 0 ? -1 - val : val;
178
179 // Hopefully, this loop can be unrolled.
180 for(unsigned int i = length * size_t_bits; i > 0; i -= size_t_bits)
181 {
182 seed ^= (std::size_t) (positive >> i) + (seed<<6) + (seed>>2);
183 }
184 seed ^= (std::size_t) val + (seed<<6) + (seed>>2);
185
186 return seed;
187 }
188
189 template <class T>
190 inline std::size_t hash_value_unsigned(T val)
191 {
192 const int size_t_bits = std::numeric_limits<std::size_t>::digits;
193 // ceiling(std::numeric_limits<T>::digits / size_t_bits) - 1
194 const int length = (std::numeric_limits<T>::digits - 1)
195 / size_t_bits;
196
197 std::size_t seed = 0;
198
199 // Hopefully, this loop can be unrolled.
200 for(unsigned int i = length * size_t_bits; i > 0; i -= size_t_bits)
201 {
202 seed ^= (std::size_t) (val >> i) + (seed<<6) + (seed>>2);
203 }
204 seed ^= (std::size_t) val + (seed<<6) + (seed>>2);
205
206 return seed;
207 }
208
209 template <typename SizeT>
210 inline void hash_combine_impl(SizeT& seed, SizeT value)
211 {
212 seed ^= value + 0x9e3779b9 + (seed<<6) + (seed>>2);
213 }
214
215 template <typename SizeT>
216 inline void hash_combine_impl(boost::uint32_t& h1,
217 boost::uint32_t k1)
218 {
219 const uint32_t c1 = 0xcc9e2d51;
220 const uint32_t c2 = 0x1b873593;
221
222 k1 *= c1;
223 k1 = BOOST_FUNCTIONAL_HASH_ROTL32(k1,15);
224 k1 *= c2;
225
226 h1 ^= k1;
227 h1 = BOOST_FUNCTIONAL_HASH_ROTL32(h1,13);
228 h1 = h1*5+0xe6546b64;
229 }
230
231
232// Don't define 64-bit hash combine on platforms with 64 bit integers,
233// and also not for 32-bit gcc as it warns about the 64-bit constant.
234#if !defined(BOOST_NO_INT64_T) && \
235 !(defined(__GNUC__) && ULONG_MAX == 0xffffffff)
236
237 template <typename SizeT>
238 inline void hash_combine_impl(boost::uint64_t& h,
239 boost::uint64_t k)
240 {
241 const uint64_t m = UINT64_C(0xc6a4a7935bd1e995);
242 const int r = 47;
243
244 k *= m;
245 k ^= k >> r;
246 k *= m;
247
248 h ^= k;
249 h *= m;
250 }
251
252#endif // BOOST_NO_INT64_T
253 }
254
255 template <typename T>
256 typename boost::hash_detail::basic_numbers<T>::type hash_value(T v)
257 {
258 return static_cast<std::size_t>(v);
259 }
260
261 template <typename T>
262 typename boost::hash_detail::long_numbers<T>::type hash_value(T v)
263 {
264 return hash_detail::hash_value_signed(v);
265 }
266
267 template <typename T>
268 typename boost::hash_detail::ulong_numbers<T>::type hash_value(T v)
269 {
270 return hash_detail::hash_value_unsigned(v);
271 }
272
273 template <typename T>
274 typename boost::enable_if<boost::is_enum<T>, std::size_t>::type
275 hash_value(T v)
276 {
277 return static_cast<std::size_t>(v);
278 }
279
280 // Implementation by Alberto Barbati and Dave Harris.
281#if !BOOST_WORKAROUND(__DMC__, <= 0x848)
282 template <class T> std::size_t hash_value(T* const& v)
283#else
284 template <class T> std::size_t hash_value(T* v)
285#endif
286 {
287#if defined(__VMS) && __INITIAL_POINTER_SIZE == 64
288 // for some reason ptrdiff_t on OpenVMS compiler with
289 // 64 bit is not 64 bit !!!
290 std::size_t x = static_cast<std::size_t>(
291 reinterpret_cast<long long int>(v));
292#else
293 std::size_t x = static_cast<std::size_t>(
294 reinterpret_cast<std::ptrdiff_t>(v));
295#endif
296 return x + (x >> 3);
297 }
298
299#if defined(BOOST_MSVC)
300#pragma warning(push)
301#if BOOST_MSVC <= 1400
302#pragma warning(disable:4267) // 'argument' : conversion from 'size_t' to
303 // 'unsigned int', possible loss of data
304 // A misguided attempt to detect 64-bit
305 // incompatability.
306#endif
307#endif
308
309 template <class T>
310 inline void hash_combine(std::size_t& seed, T const& v)
311 {
312 boost::hash<T> hasher;
313 return boost::hash_detail::hash_combine_impl(seed, hasher(v));
314 }
315
316#if defined(BOOST_MSVC)
317#pragma warning(pop)
318#endif
319
320 template <class It>
321 inline std::size_t hash_range(It first, It last)
322 {
323 std::size_t seed = 0;
324
325 for(; first != last; ++first)
326 {
327 hash_combine(seed, *first);
328 }
329
330 return seed;
331 }
332
333 template <class It>
334 inline void hash_range(std::size_t& seed, It first, It last)
335 {
336 for(; first != last; ++first)
337 {
338 hash_combine(seed, *first);
339 }
340 }
341
342#if BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x551))
343 template <class T>
344 inline std::size_t hash_range(T* first, T* last)
345 {
346 std::size_t seed = 0;
347
348 for(; first != last; ++first)
349 {
350 boost::hash<T> hasher;
351 seed ^= hasher(*first) + 0x9e3779b9 + (seed<<6) + (seed>>2);
352 }
353
354 return seed;
355 }
356
357 template <class T>
358 inline void hash_range(std::size_t& seed, T* first, T* last)
359 {
360 for(; first != last; ++first)
361 {
362 boost::hash<T> hasher;
363 seed ^= hasher(*first) + 0x9e3779b9 + (seed<<6) + (seed>>2);
364 }
365 }
366#endif
367
368#if !defined(BOOST_NO_FUNCTION_TEMPLATE_ORDERING)
369 template< class T, unsigned N >
370 inline std::size_t hash_value(const T (&x)[N])
371 {
372 return hash_range(x, x + N);
373 }
374
375 template< class T, unsigned N >
376 inline std::size_t hash_value(T (&x)[N])
377 {
378 return hash_range(x, x + N);
379 }
380#endif
381
382 template <class Ch, class A>
383 inline std::size_t hash_value(
384 std::basic_string<Ch, std::BOOST_HASH_CHAR_TRAITS<Ch>, A> const& v)
385 {
386 return hash_range(v.begin(), v.end());
387 }
388
389 template <typename T>
390 typename boost::hash_detail::float_numbers<T>::type hash_value(T v)
391 {
392 return boost::hash_detail::float_hash_value(v);
393 }
394
395#if !defined(BOOST_NO_CXX11_HDR_TYPEINDEX)
396 inline std::size_t hash_value(std::type_index v)
397 {
398 return v.hash_code();
399 }
400#endif
401
402 //
403 // boost::hash
404 //
405
406 // Define the specializations required by the standard. The general purpose
407 // boost::hash is defined later in extensions.hpp if
408 // BOOST_HASH_NO_EXTENSIONS is not defined.
409
410 // BOOST_HASH_SPECIALIZE - define a specialization for a type which is
411 // passed by copy.
412 //
413 // BOOST_HASH_SPECIALIZE_REF - define a specialization for a type which is
414 // passed by const reference.
415 //
416 // These are undefined later.
417
418#define BOOST_HASH_SPECIALIZE(type) \
419 template <> struct hash<type> \
420 : public std::unary_function<type, std::size_t> \
421 { \
422 std::size_t operator()(type v) const \
423 { \
424 return boost::hash_value(v); \
425 } \
426 };
427
428#define BOOST_HASH_SPECIALIZE_REF(type) \
429 template <> struct hash<type> \
430 : public std::unary_function<type, std::size_t> \
431 { \
432 std::size_t operator()(type const& v) const \
433 { \
434 return boost::hash_value(v); \
435 } \
436 };
437
438 BOOST_HASH_SPECIALIZE(bool)
439 BOOST_HASH_SPECIALIZE(char)
440 BOOST_HASH_SPECIALIZE(signed char)
441 BOOST_HASH_SPECIALIZE(unsigned char)
442#if !defined(BOOST_NO_INTRINSIC_WCHAR_T)
443 BOOST_HASH_SPECIALIZE(wchar_t)
444#endif
445 BOOST_HASH_SPECIALIZE(short)
446 BOOST_HASH_SPECIALIZE(unsigned short)
447 BOOST_HASH_SPECIALIZE(int)
448 BOOST_HASH_SPECIALIZE(unsigned int)
449 BOOST_HASH_SPECIALIZE(long)
450 BOOST_HASH_SPECIALIZE(unsigned long)
451
452 BOOST_HASH_SPECIALIZE(float)
453 BOOST_HASH_SPECIALIZE(double)
454 BOOST_HASH_SPECIALIZE(long double)
455
456 BOOST_HASH_SPECIALIZE_REF(std::string)
457#if !defined(BOOST_NO_STD_WSTRING)
458 BOOST_HASH_SPECIALIZE_REF(std::wstring)
459#endif
460
461#if !defined(BOOST_NO_LONG_LONG)
462 BOOST_HASH_SPECIALIZE(boost::long_long_type)
463 BOOST_HASH_SPECIALIZE(boost::ulong_long_type)
464#endif
465
466#if defined(BOOST_HAS_INT128)
467 BOOST_HASH_SPECIALIZE(boost::int128_type)
468 BOOST_HASH_SPECIALIZE(boost::uint128_type)
469#endif
470
471#if !defined(BOOST_NO_CXX11_HDR_TYPEINDEX)
472 BOOST_HASH_SPECIALIZE(std::type_index)
473#endif
474
475#undef BOOST_HASH_SPECIALIZE
476#undef BOOST_HASH_SPECIALIZE_REF
477
478// Specializing boost::hash for pointers.
479
480#if !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
481
482 template <class T>
483 struct hash<T*>
484 : public std::unary_function<T*, std::size_t>
485 {
486 std::size_t operator()(T* v) const
487 {
488#if !BOOST_WORKAROUND(__SUNPRO_CC, <= 0x590)
489 return boost::hash_value(v);
490#else
491 std::size_t x = static_cast<std::size_t>(
492 reinterpret_cast<std::ptrdiff_t>(v));
493
494 return x + (x >> 3);
495#endif
496 }
497 };
498
499#else
500
501 // For compilers without partial specialization, we define a
502 // boost::hash for all remaining types. But hash_impl is only defined
503 // for pointers in 'extensions.hpp' - so when BOOST_HASH_NO_EXTENSIONS
504 // is defined there will still be a compile error for types not supported
505 // in the standard.
506
507 namespace hash_detail
508 {
509 template <bool IsPointer>
510 struct hash_impl;
511
512 template <>
513 struct hash_impl<true>
514 {
515 template <class T>
516 struct inner
517 : public std::unary_function<T, std::size_t>
518 {
519 std::size_t operator()(T val) const
520 {
521#if !BOOST_WORKAROUND(__SUNPRO_CC, <= 590)
522 return boost::hash_value(val);
523#else
524 std::size_t x = static_cast<std::size_t>(
525 reinterpret_cast<std::ptrdiff_t>(val));
526
527 return x + (x >> 3);
528#endif
529 }
530 };
531 };
532 }
533
534 template <class T> struct hash
535 : public boost::hash_detail::hash_impl<boost::is_pointer<T>::value>
536 ::BOOST_NESTED_TEMPLATE inner<T>
537 {
538 };
539
540#endif
541}
542
543#undef BOOST_HASH_CHAR_TRAITS
544#undef BOOST_FUNCTIONAL_HASH_ROTL32
545
546#if defined(BOOST_MSVC)
547#pragma warning(pop)
548#endif
549
550#endif // BOOST_FUNCTIONAL_HASH_HASH_HPP
551
552// Include this outside of the include guards in case the file is included
553// twice - once with BOOST_HASH_NO_EXTENSIONS defined, and then with it
554// undefined.
555
556#if !defined(BOOST_HASH_NO_EXTENSIONS) \
557 && !defined(BOOST_FUNCTIONAL_HASH_EXTENSIONS_HPP)
558#include <boost/functional/hash/extensions.hpp>
559#endif
560