1 /////////////////////////////////////////////////////////////////////////////
3 // Purpose: wxHashMap class
4 // Author: Mattia Barbon
8 // Copyright: (c) Mattia Barbon
9 // Licence: wxWindows licence
10 /////////////////////////////////////////////////////////////////////////////
12 #ifndef _WX_HASHMAP_H_
13 #define _WX_HASHMAP_H_
15 #if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
16 #pragma interface "hashmap.h"
19 #include "wx/string.h"
21 #if (defined(HAVE_EXT_HASH_MAP) || defined(HAVE_HASH_MAP)) \
22 && (defined(HAVE_GNU_CXX_HASH_MAP) || defined(HAVE_STD_HASH_MAP))
23 #define HAVE_STL_HASH_MAP
26 #if wxUSE_STL && defined(HAVE_STL_HASH_MAP)
28 #if defined(HAVE_EXT_HASH_MAP)
29 #include <ext/hash_map>
30 #elif defined(HAVE_HASH_MAP)
34 #if defined(HAVE_GNU_CXX_HASH_MAP)
35 #define WX_HASH_MAP_NAMESPACE __gnu_cxx
36 #elif defined(HAVE_STD_HASH_MAP)
37 #define WX_HASH_MAP_NAMESPACE std
40 #define _WX_DECLARE_HASH_MAP( KEY_T, VALUE_T, HASH_T, KEY_EQ_T, CLASSNAME, CLASSEXP ) \
41 typedef WX_HASH_MAP_NAMESPACE::hash_map< KEY_T, VALUE_T, HASH_T, KEY_EQ_T > CLASSNAME;
43 #else // !wxUSE_STL || !defined(HAVE_STL_HASH_MAP)
45 #include <stddef.h> // for ptrdiff_t
48 typedef int ptrdiff_t;
52 struct WXDLLIMPEXP_BASE _wxHashTable_NodeBase
54 _wxHashTable_NodeBase() : m_nxt(0) {}
56 _wxHashTable_NodeBase
* m_nxt
;
59 // DECLARE_NO_COPY_CLASS(_wxHashTable_NodeBase)
60 // without rewriting the macros, which require a public copy constructor.
64 class WXDLLIMPEXP_BASE _wxHashTableBase2
67 typedef void (*NodeDtor
)(_wxHashTable_NodeBase
*);
68 typedef unsigned long (*BucketFromNode
)(_wxHashTableBase2
*,_wxHashTable_NodeBase
*);
69 typedef _wxHashTable_NodeBase
* (*ProcessNode
)(_wxHashTable_NodeBase
*);
71 static _wxHashTable_NodeBase
* DummyProcessNode(_wxHashTable_NodeBase
* node
);
72 static void DeleteNodes( size_t buckets
, _wxHashTable_NodeBase
** table
,
74 static _wxHashTable_NodeBase
* GetFirstNode( size_t buckets
,
75 _wxHashTable_NodeBase
** table
)
77 for( size_t i
= 0; i
< buckets
; ++i
)
83 // as static const unsigned prime_count = 31 but works with all compilers
84 enum { prime_count
= 31 };
85 static const unsigned long ms_primes
[prime_count
];
87 // returns the first prime in ms_primes greater than n
88 static unsigned long GetNextPrime( unsigned long n
);
90 // returns the first prime in ms_primes smaller than n
91 // ( or ms_primes[0] if n is very small )
92 static unsigned long GetPreviousPrime( unsigned long n
);
94 static void CopyHashTable( _wxHashTable_NodeBase
** srcTable
,
95 size_t srcBuckets
, _wxHashTableBase2
* dst
,
96 _wxHashTable_NodeBase
** dstTable
,
97 BucketFromNode func
, ProcessNode proc
);
99 static void** AllocTable( size_t sz
)
101 return (void **)calloc(sz
, sizeof(void*));
105 #define _WX_DECLARE_HASHTABLE( VALUE_T, KEY_T, HASH_T, KEY_EX_T, KEY_EQ_T, CLASSNAME, CLASSEXP, SHOULD_GROW, SHOULD_SHRINK ) \
106 CLASSEXP CLASSNAME : protected _wxHashTableBase2 \
109 typedef KEY_T key_type; \
110 typedef VALUE_T value_type; \
111 typedef HASH_T hasher; \
112 typedef KEY_EQ_T key_equal; \
114 typedef size_t size_type; \
115 typedef ptrdiff_t difference_type; \
116 typedef value_type* pointer; \
117 typedef const value_type* const_pointer; \
118 typedef value_type& reference; \
119 typedef const value_type& const_reference; \
120 /* should these be protected? */ \
121 typedef const KEY_T const_key_type; \
122 typedef const VALUE_T const_mapped_type; \
125 typedef KEY_EX_T key_extractor; \
126 typedef CLASSNAME Self; \
129 size_t m_tableBuckets; \
132 key_equal m_equals; \
133 key_extractor m_getKey; \
135 struct Node:public _wxHashTable_NodeBase \
138 Node( const value_type& value ) \
139 : m_value( value ) {} \
140 Node* m_next() { return (Node*)this->m_nxt; } \
142 value_type m_value; \
146 friend struct Iterator; \
148 static void DeleteNode( _wxHashTable_NodeBase* node ) \
150 delete (Node*)node; \
154 /* forward iterator */ \
161 Iterator() : m_node(0), m_ht(0) {} \
162 Iterator( Node* node, const Self* ht ) \
163 : m_node(node), m_ht((Self*)ht) {} \
164 bool operator ==( const Iterator& it ) const \
165 { return m_node == it.m_node; } \
166 bool operator !=( const Iterator& it ) const \
167 { return m_node != it.m_node; } \
169 Node* GetNextNode() \
171 size_type bucket = GetBucketForNode(m_ht,m_node); \
172 for( size_type i = bucket + 1; i < m_ht->m_tableBuckets; ++i ) \
174 if( m_ht->m_table[i] ) \
175 return m_ht->m_table[i]; \
182 Node* next = m_node->m_next(); \
183 m_node = next ? next : GetNextNode(); \
188 struct iterator:public Iterator \
190 iterator() : Iterator() {} \
191 iterator( Node* node, Self* ht ) : Iterator( node, ht ) {} \
192 iterator& operator++() { PlusPlus(); return *this; } \
193 iterator operator++(int) { iterator it=*this;PlusPlus();return it; } \
194 reference operator *() const { return m_node->m_value; } \
195 pointer operator ->() const { return &(m_node->m_value); } \
198 struct const_iterator:public Iterator \
200 const_iterator() : Iterator() {} \
201 const_iterator( Node* node, const Self* ht ) \
202 : Iterator( node, (Self*)ht ) {} \
203 const_iterator& operator++() { PlusPlus();return *this; } \
204 const_iterator operator++(int) { const_iterator it=*this;PlusPlus();return it; } \
205 const_reference operator *() const { return m_node->m_value; } \
206 const_pointer operator ->() const { return &(m_node->m_value); } \
209 CLASSNAME( size_type sz = 10, const hasher& hfun = hasher(), \
210 const key_equal& k_eq = key_equal(), \
211 const key_extractor& k_ex = key_extractor() ) \
212 : m_tableBuckets( GetNextPrime( (unsigned long) sz ) ), \
218 m_table = (Node**)AllocTable( m_tableBuckets ); \
221 CLASSNAME( const Self& ht ) \
223 m_tableBuckets( 0 ), \
224 m_items( ht.m_items ), \
225 m_hasher( ht.m_hasher ), \
226 m_equals( ht.m_equals ), \
227 m_getKey( ht.m_getKey ) \
232 const Self& operator=( const Self& ht ) \
235 m_hasher = ht.m_hasher; \
236 m_equals = ht.m_equals; \
237 m_getKey = ht.m_getKey; \
238 m_items = ht.m_items; \
250 hasher hash_funct() { return m_hasher; } \
251 key_equal key_eq() { return m_equals; } \
253 /* removes all elements from the hash table, but does not */ \
254 /* shrink it ( perhaps it should ) */ \
257 DeleteNodes( m_tableBuckets, (_wxHashTable_NodeBase**)m_table, \
262 size_type size() const { return m_items; } \
263 size_type max_size() const { return size_type(-1); } \
264 bool empty() const { return size() == 0; } \
266 const_iterator end() const { return const_iterator( 0, this ); } \
267 iterator end() { return iterator( 0, this ); } \
268 const_iterator begin() const \
269 { return const_iterator( (Node*)GetFirstNode( m_tableBuckets, (_wxHashTable_NodeBase**)m_table ), this ); }; \
271 { return iterator( (Node*)GetFirstNode( m_tableBuckets, (_wxHashTable_NodeBase**)m_table ), this ); }; \
273 size_type erase( const const_key_type& key ) \
275 Node** node = GetNodePtr( key ); \
281 Node* temp = (*node)->m_next(); \
284 if( SHOULD_SHRINK( m_tableBuckets, m_items ) ) \
285 ResizeTable( GetPreviousPrime( (unsigned long) m_tableBuckets ) - 1 ); \
290 static size_type GetBucketForNode( Self* ht, Node* node ) \
292 return ht->m_hasher( ht->m_getKey( node->m_value ) ) \
293 % ht->m_tableBuckets; \
295 static Node* CopyNode( Node* node ) { return new Node( *node ); } \
297 Node* GetOrCreateNode( const value_type& value ) \
299 const const_key_type& key = m_getKey( value ); \
300 size_t bucket = m_hasher( key ) % m_tableBuckets; \
301 Node* node = m_table[bucket]; \
305 if( m_equals( m_getKey( node->m_value ), key ) ) \
307 node = node->m_next(); \
309 return CreateNode( value , bucket); \
311 Node * CreateNode( const value_type& value, size_t bucket ) \
313 Node* node = new Node( value ); \
314 node->m_nxt = m_table[bucket]; \
315 m_table[bucket] = node; \
317 /* must be after the node is inserted */ \
319 if( SHOULD_GROW( m_tableBuckets, m_items ) ) \
320 ResizeTable( m_tableBuckets ); \
324 void CreateNode( const value_type& value ) \
326 CreateNode(value, m_hasher( m_getKey(value) ) % m_tableBuckets ); \
329 /* returns NULL if not found */ \
330 Node** GetNodePtr( const const_key_type& key ) const \
332 unsigned long hash = m_hasher( key ); \
333 Node** node = &m_table[hash % m_tableBuckets]; \
337 if( m_equals( m_getKey( (*node)->m_value ), key ) ) \
339 node = (Node**)&(*node)->m_nxt; \
345 /* returns NULL if not found */ \
346 /* expressing it in terms of GetNodePtr is 5-8% slower :-( */ \
347 Node* GetNode( const const_key_type& key ) const \
349 unsigned long hash = m_hasher( key ); \
350 Node* node = m_table[hash % m_tableBuckets]; \
354 if( m_equals( m_getKey( node->m_value ), key ) ) \
356 node = node->m_next(); \
362 void ResizeTable( size_t newSize ) \
364 newSize = GetNextPrime( (unsigned long)newSize ); \
365 Node** srcTable = m_table; \
366 size_t srcBuckets = m_tableBuckets; \
367 m_table = (Node**)AllocTable( newSize ); \
368 m_tableBuckets = newSize; \
370 CopyHashTable( (_wxHashTable_NodeBase**)srcTable, srcBuckets, \
371 this, (_wxHashTable_NodeBase**)m_table, \
372 (BucketFromNode)GetBucketForNode,\
373 (ProcessNode)&DummyProcessNode ); \
377 /* this must be called _after_ m_table has been cleaned */ \
378 void HashCopy( const Self& ht ) \
380 ResizeTable( ht.size() ); \
381 CopyHashTable( (_wxHashTable_NodeBase**)ht.m_table, ht.m_tableBuckets,\
382 (_wxHashTableBase2*)this, \
383 (_wxHashTable_NodeBase**)m_table, \
384 (BucketFromNode)GetBucketForNode, \
385 (ProcessNode)CopyNode ); \
389 // defines an STL-like pair class CLASSNAME storing two fields: first of type
390 // KEY_T and second of type VALUE_T
391 #define _WX_DECLARE_PAIR( KEY_T, VALUE_T, CLASSNAME, CLASSEXP ) \
396 typedef VALUE_T t2; \
397 typedef const KEY_T const_t1; \
398 typedef const VALUE_T const_t2; \
400 CLASSNAME( const const_t1& f, const const_t2& s ):first(t1(f)),second(t2(s)) {} \
406 // defines the class CLASSNAME returning the key part (of type KEY_T) from a
407 // pair of type PAIR_T
408 #define _WX_DECLARE_HASH_MAP_KEY_EX( KEY_T, PAIR_T, CLASSNAME, CLASSEXP ) \
411 typedef KEY_T key_type; \
412 typedef PAIR_T pair_type; \
413 typedef const key_type const_key_type; \
414 typedef const pair_type const_pair_type; \
415 typedef const_key_type& const_key_reference; \
416 typedef const_pair_type& const_pair_reference; \
419 const_key_reference operator()( const_pair_reference pair ) const { return pair.first; }\
421 /* the dummy assignment operator is needed to suppress compiler */ \
422 /* warnings from hash table class' operator=(): gcc complains about */ \
423 /* "statement with no effect" without it */ \
424 CLASSNAME& operator=(const CLASSNAME&) { return *this; } \
427 // grow/shrink predicates
428 inline bool never_grow( size_t, size_t ) { return FALSE
; }
429 inline bool never_shrink( size_t, size_t ) { return FALSE
; }
430 inline bool grow_lf70( size_t buckets
, size_t items
)
432 return float(items
)/float(buckets
) >= 0.85;
435 #endif // !wxUSE_STL || !defined(HAVE_STL_HASH_MAP)
437 // ----------------------------------------------------------------------------
438 // hashing and comparison functors
439 // ----------------------------------------------------------------------------
441 // NB: implementation detail: all of these classes must have dummy assignment
442 // operators to suppress warnings about "statement with no effect" from gcc
443 // in the hash table class assignment operator (where they're assigned)
445 #if wxUSE_STL && defined(HAVE_STL_HASH_MAP)
448 class WXDLLIMPEXP_BASE wxIntegerHash
450 WX_HASH_MAP_NAMESPACE::hash
<long> longHash
;
451 WX_HASH_MAP_NAMESPACE::hash
<unsigned long> ulongHash
;
452 WX_HASH_MAP_NAMESPACE::hash
<int> intHash
;
453 WX_HASH_MAP_NAMESPACE::hash
<unsigned int> uintHash
;
454 WX_HASH_MAP_NAMESPACE::hash
<short> shortHash
;
455 WX_HASH_MAP_NAMESPACE::hash
<unsigned short> ushortHash
;
458 size_t operator()( long x
) const { return longHash( x
); }
459 size_t operator()( unsigned long x
) const { return ulongHash( x
); }
460 size_t operator()( int x
) const { return intHash( x
); }
461 size_t operator()( unsigned int x
) const { return uintHash( x
); }
462 size_t operator()( short x
) const { return shortHash( x
); }
463 size_t operator()( unsigned short x
) const { return ushortHash( x
); }
465 wxIntegerHash
& operator=(const wxIntegerHash
&) { return *this; }
468 #else // !wxUSE_STL || !defined(HAVE_STL_HASH_MAP)
471 class WXDLLIMPEXP_BASE wxIntegerHash
475 unsigned long operator()( long x
) const { return (unsigned long)x
; }
476 unsigned long operator()( unsigned long x
) const { return x
; }
477 unsigned long operator()( int x
) const { return (unsigned long)x
; }
478 unsigned long operator()( unsigned int x
) const { return x
; }
479 unsigned long operator()( short x
) const { return (unsigned long)x
; }
480 unsigned long operator()( unsigned short x
) const { return x
; }
482 wxIntegerHash
& operator=(const wxIntegerHash
&) { return *this; }
485 #endif // !wxUSE_STL || !defined(HAVE_STL_HASH_MAP)
487 class WXDLLIMPEXP_BASE wxIntegerEqual
491 bool operator()( long a
, long b
) const { return a
== b
; }
492 bool operator()( unsigned long a
, unsigned long b
) const { return a
== b
; }
493 bool operator()( int a
, int b
) const { return a
== b
; }
494 bool operator()( unsigned int a
, unsigned int b
) const { return a
== b
; }
495 bool operator()( short a
, short b
) const { return a
== b
; }
496 bool operator()( unsigned short a
, unsigned short b
) const { return a
== b
; }
498 wxIntegerEqual
& operator=(const wxIntegerEqual
&) { return *this; }
502 class WXDLLIMPEXP_BASE wxPointerHash
507 // TODO: this might not work well on architectures with 64 bit pointers but
508 // 32 bit longs, we should use % ULONG_MAX there
509 #if wxUSE_STL && defined(HAVE_STL_HASH_MAP)
510 size_t operator()( const void* k
) const { return (size_t)k
; }
512 unsigned long operator()( const void* k
) const { return (unsigned long)wxPtrToULong(k
); }
515 wxPointerHash
& operator=(const wxPointerHash
&) { return *this; }
518 class WXDLLIMPEXP_BASE wxPointerEqual
522 bool operator()( const void* a
, const void* b
) const { return a
== b
; }
524 wxPointerEqual
& operator=(const wxPointerEqual
&) { return *this; }
527 // wxString, char*, wxChar*
528 class WXDLLIMPEXP_BASE wxStringHash
532 unsigned long operator()( const wxString
& x
) const
533 { return wxCharStringHash( x
.c_str() ); }
534 unsigned long operator()( const wxChar
* x
) const
535 { return wxCharStringHash( x
); }
536 static unsigned long wxCharStringHash( const wxChar
* );
538 unsigned long operator()( const char* x
) const
539 { return charStringHash( x
); }
540 static unsigned long charStringHash( const char* );
541 #endif // wxUSE_UNICODE
543 wxStringHash
& operator=(const wxStringHash
&) { return *this; }
546 class WXDLLIMPEXP_BASE wxStringEqual
550 bool operator()( const wxString
& a
, const wxString
& b
) const
552 bool operator()( const wxChar
* a
, const wxChar
* b
) const
553 { return wxStrcmp( a
, b
) == 0; }
555 bool operator()( const char* a
, const char* b
) const
556 { return strcmp( a
, b
) == 0; }
557 #endif // wxUSE_UNICODE
559 wxStringEqual
& operator=(const wxStringEqual
&) { return *this; }
562 #if !wxUSE_STL || !defined(HAVE_STL_HASH_MAP)
564 #define _WX_DECLARE_HASH_MAP( KEY_T, VALUE_T, HASH_T, KEY_EQ_T, CLASSNAME, CLASSEXP ) \
565 _WX_DECLARE_PAIR( KEY_T, VALUE_T, CLASSNAME##_wxImplementation_Pair, CLASSEXP ) \
566 _WX_DECLARE_HASH_MAP_KEY_EX( KEY_T, CLASSNAME##_wxImplementation_Pair, CLASSNAME##_wxImplementation_KeyEx, CLASSEXP ) \
567 _WX_DECLARE_HASHTABLE( CLASSNAME##_wxImplementation_Pair, KEY_T, HASH_T, CLASSNAME##_wxImplementation_KeyEx, KEY_EQ_T, CLASSNAME##_wxImplementation_HashTable, CLASSEXP, grow_lf70, never_shrink ) \
568 CLASSEXP CLASSNAME:public CLASSNAME##_wxImplementation_HashTable \
571 typedef VALUE_T mapped_type; \
573 wxEXPLICIT CLASSNAME( size_type hint = 100, hasher hf = hasher(), \
574 key_equal eq = key_equal() ) \
575 : CLASSNAME##_wxImplementation_HashTable( hint, hf, eq, \
576 CLASSNAME##_wxImplementation_KeyEx() ) {} \
578 mapped_type& operator[]( const const_key_type& key ) \
580 return GetOrCreateNode( CLASSNAME##_wxImplementation_Pair( key, mapped_type() ) )->m_value.second; \
583 const_iterator find( const const_key_type& key ) const \
585 return const_iterator( GetNode( key ), this ); \
588 iterator find( const const_key_type& key ) \
590 return iterator( GetNode( key ), this ); \
593 void insert( const value_type& v ) { (*this)[v.first] = v.second; } \
595 size_type erase( const key_type& k ) \
596 { return CLASSNAME##_wxImplementation_HashTable::erase( k ); } \
597 void erase( const iterator& it ) { erase( it->first ); } \
598 void erase( const const_iterator& it ) { erase( it->first ); } \
600 /* count() == 0 | 1 */ \
601 size_type count( const const_key_type& key ) \
602 { return GetNode( key ) ? 1 : 0; } \
605 #endif // !wxUSE_STL || !defined(HAVE_STL_HASH_MAP)
607 // these macros are to be used in the user code
608 #define WX_DECLARE_HASH_MAP( KEY_T, VALUE_T, HASH_T, KEY_EQ_T, CLASSNAME) \
609 _WX_DECLARE_HASH_MAP( KEY_T, VALUE_T, HASH_T, KEY_EQ_T, CLASSNAME, class )
611 #define WX_DECLARE_STRING_HASH_MAP( VALUE_T, CLASSNAME ) \
612 _WX_DECLARE_HASH_MAP( wxString, VALUE_T, wxStringHash, wxStringEqual, \
615 #define WX_DECLARE_VOIDPTR_HASH_MAP( VALUE_T, CLASSNAME ) \
616 _WX_DECLARE_HASH_MAP( void*, VALUE_T, wxPointerHash, wxPointerEqual, \
619 // and these do exactly the same thing but should be used inside the
621 #define WX_DECLARE_HASH_MAP_WITH_DECL( KEY_T, VALUE_T, HASH_T, KEY_EQ_T, CLASSNAME, DECL) \
622 _WX_DECLARE_HASH_MAP( KEY_T, VALUE_T, HASH_T, KEY_EQ_T, CLASSNAME, DECL )
624 #define WX_DECLARE_EXPORTED_HASH_MAP( KEY_T, VALUE_T, HASH_T, KEY_EQ_T, CLASSNAME) \
625 WX_DECLARE_HASH_MAP_WITH_DECL( KEY_T, VALUE_T, HASH_T, KEY_EQ_T, \
626 CLASSNAME, class WXDLLEXPORT )
628 #define WX_DECLARE_STRING_HASH_MAP_WITH_DECL( VALUE_T, CLASSNAME, DECL ) \
629 _WX_DECLARE_HASH_MAP( wxString, VALUE_T, wxStringHash, wxStringEqual, \
632 #define WX_DECLARE_EXPORTED_STRING_HASH_MAP( VALUE_T, CLASSNAME ) \
633 WX_DECLARE_STRING_HASH_MAP_WITH_DECL( VALUE_T, CLASSNAME, \
636 #define WX_DECLARE_VOIDPTR_HASH_MAP_WITH_DECL( VALUE_T, CLASSNAME, DECL ) \
637 _WX_DECLARE_HASH_MAP( void*, VALUE_T, wxPointerHash, wxPointerEqual, \
640 #define WX_DECLARE_EXPORTED_VOIDPTR_HASH_MAP( VALUE_T, CLASSNAME ) \
641 WX_DECLARE_VOIDPTR_HASH_MAP_WITH_DECL( VALUE_T, CLASSNAME, \
644 // delete all hash elements
646 // NB: the class declaration of the hash elements must be visible from the
647 // place where you use this macro, otherwise the proper destructor may not
648 // be called (a decent compiler should give a warning about it, but don't
650 #define WX_CLEAR_HASH_MAP(type, hashmap) \
652 type::iterator it, en; \
653 for( it = (hashmap).begin(), en = (hashmap).end(); it != en; ++it ) \
658 //---------------------------------------------------------------------------
659 // Declarations of common hashmap classes
661 WX_DECLARE_HASH_MAP_WITH_DECL( long, long, wxIntegerHash
, wxIntegerEqual
,
662 wxLongToLongHashMap
, class WXDLLIMPEXP_BASE
);
665 #endif // _WX_HASHMAP_H_