///////////////////////////////////////////////////////////////////////////// // Name: hashmap.h // Purpose: wxHashMap class // Author: Mattia Barbon // Modified by: // Created: 29/01/2002 // RCS-ID: $Id$ // Copyright: (c) Mattia Barbon // Licence: wxWindows licence ///////////////////////////////////////////////////////////////////////////// #ifndef _WX_HASHMAP_H_ #define _WX_HASHMAP_H_ #if defined(__GNUG__) && !defined(NO_GCC_PRAGMA) #pragma interface "hashmap.h" #endif #include "wx/string.h" #include // for ptrdiff_t #ifdef __WXWINCE__ typedef int ptrdiff_t; #endif // private struct WXDLLIMPEXP_BASE _wxHashTable_NodeBase { _wxHashTable_NodeBase() : m_nxt(0) {} _wxHashTable_NodeBase* m_nxt; // Cannot do this: // DECLARE_NO_COPY_CLASS(_wxHashTable_NodeBase) // without rewriting the macros, which require a public copy constructor. }; // private class WXDLLIMPEXP_BASE _wxHashTableBase2 { public: typedef void (*NodeDtor)(_wxHashTable_NodeBase*); typedef unsigned long (*BucketFromNode)(_wxHashTableBase2*,_wxHashTable_NodeBase*); typedef _wxHashTable_NodeBase* (*ProcessNode)(_wxHashTable_NodeBase*); protected: static _wxHashTable_NodeBase* DummyProcessNode(_wxHashTable_NodeBase* node); static void DeleteNodes( size_t buckets, _wxHashTable_NodeBase** table, NodeDtor dtor ); static _wxHashTable_NodeBase* GetFirstNode( size_t buckets, _wxHashTable_NodeBase** table ) { for( size_t i = 0; i < buckets; ++i ) if( table[i] ) return table[i]; return 0; } // as static const unsigned prime_count = 31 but works with all compilers enum { prime_count = 31 }; static const unsigned long ms_primes[prime_count]; // returns the first prime in ms_primes greater than n static unsigned long GetNextPrime( unsigned long n ); // returns the first prime in ms_primes smaller than n // ( or ms_primes[0] if n is very small ) static unsigned long GetPreviousPrime( unsigned long n ); static void CopyHashTable( _wxHashTable_NodeBase** srcTable, size_t srcBuckets, _wxHashTableBase2* dst, _wxHashTable_NodeBase** dstTable, size_t dstBuckets, BucketFromNode func, ProcessNode proc ); static void** AllocTable( size_t sz ) { return (void **)calloc(sz, sizeof(void*)); } }; #define _WX_DECLARE_HASHTABLE( VALUE_T, KEY_T, HASH_T, KEY_EX_T, KEY_EQ_T, CLASSNAME, CLASSEXP, SHOULD_GROW, SHOULD_SHRINK ) \ CLASSEXP CLASSNAME : protected _wxHashTableBase2 \ { \ public: \ typedef KEY_T key_type; \ typedef VALUE_T value_type; \ typedef HASH_T hasher; \ typedef KEY_EQ_T key_equal; \ \ typedef size_t size_type; \ typedef ptrdiff_t difference_type; \ typedef value_type* pointer; \ typedef const value_type* const_pointer; \ typedef value_type& reference; \ typedef const value_type& const_reference; \ /* should these be protected? */ \ typedef const KEY_T const_key_type; \ typedef const VALUE_T const_mapped_type; \ public: \ struct Node; \ typedef KEY_EX_T key_extractor; \ typedef CLASSNAME Self; \ protected: \ Node** m_table; \ size_t m_tableBuckets; \ size_t m_items; \ hasher m_hasher; \ key_equal m_equals; \ key_extractor m_getKey; \ public: \ struct Node:public _wxHashTable_NodeBase \ { \ public: \ Node( const value_type& value ) \ : m_value( value ) {} \ Node* m_next() { return (Node*)this->m_nxt; } \ \ value_type m_value; \ }; \ \ struct Iterator; \ friend struct Iterator; \ protected: \ static void DeleteNode( _wxHashTable_NodeBase* node ) \ { \ delete (Node*)node; \ } \ public: \ /* */ \ /* forward iterator */ \ /* */ \ struct Iterator \ { \ Node* m_node; \ Self* m_ht; \ \ Iterator() : m_node(0), m_ht(0) {} \ Iterator( Node* node, const Self* ht ) \ : m_node(node), m_ht((Self*)ht) {} \ bool operator ==( const Iterator& it ) const \ { return m_node == it.m_node; } \ bool operator !=( const Iterator& it ) const \ { return m_node != it.m_node; } \ protected: \ Node* GetNextNode() \ { \ size_type bucket = GetBucketForNode(m_ht,m_node); \ for( size_type i = bucket + 1; i < m_ht->m_tableBuckets; ++i ) \ { \ if( m_ht->m_table[i] ) \ return m_ht->m_table[i]; \ } \ return 0; \ } \ \ void PlusPlus() \ { \ Node* next = m_node->m_next(); \ m_node = next ? next : GetNextNode(); \ } \ }; \ \ public: \ struct iterator:public Iterator \ { \ iterator() : Iterator() {} \ iterator( Node* node, Self* ht ) : Iterator( node, ht ) {} \ iterator& operator++() { PlusPlus(); return *this; } \ iterator operator++(int) { iterator it=*this;PlusPlus();return it; } \ reference operator *() const { return m_node->m_value; } \ pointer operator ->() const { return &(m_node->m_value); } \ }; \ \ struct const_iterator:public Iterator \ { \ const_iterator() : Iterator() {} \ const_iterator( Node* node, const Self* ht ) \ : Iterator( node, (Self*)ht ) {} \ const_iterator& operator++() { PlusPlus();return *this; } \ const_iterator operator++(int) { const_iterator it=*this;PlusPlus();return it; } \ const_reference operator *() const { return m_node->m_value; } \ const_pointer operator ->() const { return &(m_node->m_value); } \ }; \ \ CLASSNAME( size_type sz = 10, const hasher& hfun = hasher(), \ const key_equal& k_eq = key_equal(), \ const key_extractor& k_ex = key_extractor() ) \ : m_tableBuckets( GetNextPrime( (unsigned long) sz ) ), \ m_items( 0 ), \ m_hasher( hfun ), \ m_equals( k_eq ), \ m_getKey( k_ex ) \ { \ m_table = (Node**)AllocTable( m_tableBuckets ); \ } \ \ CLASSNAME( const Self& ht ) \ : m_table( 0 ), \ m_tableBuckets( 0 ), \ m_items( ht.m_items ), \ m_hasher( ht.m_hasher ), \ m_equals( ht.m_equals ), \ m_getKey( ht.m_getKey ) \ { \ HashCopy( ht ); \ } \ \ const Self& operator=( const Self& ht ) \ { \ clear(); \ m_hasher = ht.m_hasher; \ m_equals = ht.m_equals; \ m_getKey = ht.m_getKey; \ m_items = ht.m_items; \ HashCopy( ht ); \ return *this; \ } \ \ ~CLASSNAME() \ { \ clear(); \ \ free(m_table); \ } \ \ hasher hash_funct() { return m_hasher; } \ key_equal key_eq() { return m_equals; } \ \ /* removes all elements from the hash table, but does not */ \ /* shrink it ( perhaps it should ) */ \ void clear() \ { \ DeleteNodes( m_tableBuckets, (_wxHashTable_NodeBase**)m_table, \ DeleteNode ); \ m_items = 0; \ } \ \ size_type size() const { return m_items; } \ size_type max_size() const { return size_type(-1); } \ bool empty() const { return size() == 0; } \ \ const_iterator end() const { return const_iterator( 0, this ); } \ iterator end() { return iterator( 0, this ); } \ const_iterator begin() const \ { return const_iterator( (Node*)GetFirstNode( m_tableBuckets, (_wxHashTable_NodeBase**)m_table ), this ); }; \ iterator begin() \ { return iterator( (Node*)GetFirstNode( m_tableBuckets, (_wxHashTable_NodeBase**)m_table ), this ); }; \ \ size_type erase( const const_key_type& key ) \ { \ Node** node = GetNodePtr( key ); \ \ if( !node ) \ return 0; \ \ --m_items; \ Node* temp = (*node)->m_next(); \ delete *node; \ (*node) = temp; \ if( SHOULD_SHRINK( m_tableBuckets, m_items ) ) \ ResizeTable( GetPreviousPrime( (unsigned long) m_tableBuckets ) - 1 ); \ return 1; \ } \ \ protected: \ static size_type GetBucketForNode( Self* ht, Node* node ) \ { \ return ht->m_hasher( ht->m_getKey( node->m_value ) ) \ % ht->m_tableBuckets; \ } \ static Node* CopyNode( Node* node ) { return new Node( *node ); } \ \ Node* GetOrCreateNode( const value_type& value ) \ { \ const const_key_type& key = m_getKey( value ); \ size_t bucket = m_hasher( key ) % m_tableBuckets; \ Node* node = m_table[bucket]; \ \ while( node ) \ { \ if( m_equals( m_getKey( node->m_value ), key ) ) \ return node; \ node = node->m_next(); \ } \ return CreateNode( value , bucket); \ }\ Node * CreateNode( const value_type& value, size_t bucket ) \ {\ Node* node = new Node( value ); \ node->m_nxt = m_table[bucket]; \ m_table[bucket] = node; \ \ /* must be after the node is inserted */ \ ++m_items; \ if( SHOULD_GROW( m_tableBuckets, m_items ) ) \ ResizeTable( m_tableBuckets ); \ \ return node; \ } \ void CreateNodeLast( const value_type& value ) \ { \ size_t bucket = m_hasher( m_getKey(value) ) % m_tableBuckets; \ Node* curr = m_table[bucket], \ * next = m_table[bucket]; \ while( next ) { curr = next; next = next->m_next(); } \ Node** ptr = curr ? (Node**)&curr->m_nxt : &m_table[bucket]; \ *ptr = new Node( value ); \ /* must be after the node is inserted */ \ ++m_items; \ if( SHOULD_GROW( m_tableBuckets, m_items ) ) \ ResizeTable( m_tableBuckets ); \ } \ void CreateNode( const value_type& value ) \ {\ CreateNode(value, m_hasher( m_getKey(value) ) % m_tableBuckets ); \ }\ \ /* returns NULL if not found */ \ Node** GetNodePtr( const const_key_type& key ) const \ { \ unsigned long hash = m_hasher( key ); \ Node** node = &m_table[hash % m_tableBuckets]; \ \ while( *node ) \ { \ if( m_equals( m_getKey( (*node)->m_value ), key ) ) \ return node; \ node = (Node**)&(*node)->m_nxt; \ } \ \ return 0; \ } \ \ /* returns NULL if not found */ \ /* expressing it in terms of GetNodePtr is 5-8% slower :-( */ \ Node* GetNode( const const_key_type& key ) const \ { \ unsigned long hash = m_hasher( key ); \ Node* node = m_table[hash % m_tableBuckets]; \ \ while( node ) \ { \ if( m_equals( m_getKey( node->m_value ), key ) ) \ return node; \ node = node->m_next(); \ } \ \ return 0; \ } \ \ void ResizeTable( size_t newSize ) \ { \ newSize = GetNextPrime( (unsigned long)newSize ); \ Node** srcTable = m_table; \ size_t srcBuckets = m_tableBuckets; \ m_table = (Node**)AllocTable( newSize ); \ m_tableBuckets = newSize; \ \ CopyHashTable( (_wxHashTable_NodeBase**)srcTable, srcBuckets, \ this, (_wxHashTable_NodeBase**)m_table, newSize, \ (BucketFromNode)GetBucketForNode,\ (ProcessNode)&DummyProcessNode ); \ free(srcTable); \ } \ \ /* this must be called _after_ m_table has been cleaned */ \ void HashCopy( const Self& ht ) \ { \ ResizeTable( ht.size() ); \ CopyHashTable( (_wxHashTable_NodeBase**)ht.m_table, ht.m_tableBuckets,\ (_wxHashTableBase2*)this, \ (_wxHashTable_NodeBase**)m_table, m_tableBuckets, \ (BucketFromNode)GetBucketForNode, \ (ProcessNode)CopyNode ); \ } \ }; // defines an STL-like pair class CLASSNAME storing two fields: first of type // KEY_T and second of type VALUE_T #define _WX_DECLARE_PAIR( KEY_T, VALUE_T, CLASSNAME, CLASSEXP ) \ CLASSEXP CLASSNAME \ { \ public: \ typedef KEY_T t1; \ typedef VALUE_T t2; \ typedef const KEY_T const_t1; \ typedef const VALUE_T const_t2; \ \ CLASSNAME( const const_t1& f, const const_t2& s ):first(t1(f)),second(t2(s)) {} \ \ t1 first; \ t2 second; \ }; // defines the class CLASSNAME returning the key part (of type KEY_T) from a // pair of type PAIR_T #define _WX_DECLARE_HASH_MAP_KEY_EX( KEY_T, PAIR_T, CLASSNAME, CLASSEXP ) \ CLASSEXP CLASSNAME \ { \ typedef KEY_T key_type; \ typedef PAIR_T pair_type; \ typedef const key_type const_key_type; \ typedef const pair_type const_pair_type; \ typedef const_key_type& const_key_reference; \ typedef const_pair_type& const_pair_reference; \ public: \ CLASSNAME() { } \ const_key_reference operator()( const_pair_reference pair ) const { return pair.first; }\ \ /* the dummy assignment operator is needed to suppress compiler */ \ /* warnings from hash table class' operator=(): gcc complains about */ \ /* "statement with no effect" without it */ \ CLASSNAME& operator=(const CLASSNAME&) { return *this; } \ }; // grow/shrink predicates inline bool never_grow( size_t, size_t ) { return FALSE; } inline bool never_shrink( size_t, size_t ) { return FALSE; } inline bool grow_lf70( size_t buckets, size_t items ) { return float(items)/float(buckets) >= 0.85; } // ---------------------------------------------------------------------------- // hashing and comparison functors // ---------------------------------------------------------------------------- // NB: implementation detail: all of these classes must have dummy assignment // operators to suppress warnings about "statement with no effect" from gcc // in the hash table class assignment operator (where they're assigned) // integer types class WXDLLIMPEXP_BASE wxIntegerHash { public: wxIntegerHash() { } unsigned long operator()( long x ) const { return (unsigned long)x; } unsigned long operator()( unsigned long x ) const { return x; } unsigned long operator()( int x ) const { return (unsigned long)x; } unsigned long operator()( unsigned int x ) const { return x; } unsigned long operator()( short x ) const { return (unsigned long)x; } unsigned long operator()( unsigned short x ) const { return x; } wxIntegerHash& operator=(const wxIntegerHash&) { return *this; } }; class WXDLLIMPEXP_BASE wxIntegerEqual { public: wxIntegerEqual() { } bool operator()( long a, long b ) const { return a == b; } bool operator()( unsigned long a, unsigned long b ) const { return a == b; } bool operator()( int a, int b ) const { return a == b; } bool operator()( unsigned int a, unsigned int b ) const { return a == b; } bool operator()( short a, short b ) const { return a == b; } bool operator()( unsigned short a, unsigned short b ) const { return a == b; } wxIntegerEqual& operator=(const wxIntegerEqual&) { return *this; } }; // pointers class WXDLLIMPEXP_BASE wxPointerHash { public: wxPointerHash() { } // TODO: this might not work well on architectures with 64 bit pointers but // 32 bit longs, we should use % ULONG_MAX there unsigned long operator()( const void* k ) const { return (unsigned long)wxPtrToULong(k); } wxPointerHash& operator=(const wxPointerHash&) { return *this; } }; class WXDLLIMPEXP_BASE wxPointerEqual { public: wxPointerEqual() { } bool operator()( const void* a, const void* b ) const { return a == b; } wxPointerEqual& operator=(const wxPointerEqual&) { return *this; } }; // wxString, char*, wxChar* class WXDLLIMPEXP_BASE wxStringHash { public: wxStringHash() {} unsigned long operator()( const wxString& x ) const { return wxCharStringHash( x.c_str() ); } unsigned long operator()( const wxChar* x ) const { return wxCharStringHash( x ); } static unsigned long wxCharStringHash( const wxChar* ); #if wxUSE_UNICODE unsigned long operator()( const char* x ) const { return charStringHash( x ); } static unsigned long charStringHash( const char* ); #endif // wxUSE_UNICODE wxStringHash& operator=(const wxStringHash&) { return *this; } }; class WXDLLIMPEXP_BASE wxStringEqual { public: wxStringEqual() {} bool operator()( const wxString& a, const wxString& b ) const { return a == b; } bool operator()( const wxChar* a, const wxChar* b ) const { return wxStrcmp( a, b ) == 0; } #if wxUSE_UNICODE bool operator()( const char* a, const char* b ) const { return strcmp( a, b ) == 0; } #endif // wxUSE_UNICODE wxStringEqual& operator=(const wxStringEqual&) { return *this; } }; #define _WX_DECLARE_HASH_MAP( KEY_T, VALUE_T, HASH_T, KEY_EQ_T, CLASSNAME, CLASSEXP ) \ _WX_DECLARE_PAIR( KEY_T, VALUE_T, CLASSNAME##_wxImplementation_Pair, CLASSEXP ) \ _WX_DECLARE_HASH_MAP_KEY_EX( KEY_T, CLASSNAME##_wxImplementation_Pair, CLASSNAME##_wxImplementation_KeyEx, CLASSEXP ) \ _WX_DECLARE_HASHTABLE( CLASSNAME##_wxImplementation_Pair, KEY_T, HASH_T, CLASSNAME##_wxImplementation_KeyEx, KEY_EQ_T, CLASSNAME##_wxImplementation_HashTable, CLASSEXP, grow_lf70, never_shrink ) \ CLASSEXP CLASSNAME:public CLASSNAME##_wxImplementation_HashTable \ { \ public: \ typedef VALUE_T mapped_type; \ \ wxEXPLICIT CLASSNAME( size_type hint = 100, hasher hf = hasher(), \ key_equal eq = key_equal() ) \ : CLASSNAME##_wxImplementation_HashTable( hint, hf, eq, \ CLASSNAME##_wxImplementation_KeyEx() ) {} \ \ mapped_type& operator[]( const const_key_type& key ) \ { \ return GetOrCreateNode( CLASSNAME##_wxImplementation_Pair( key, mapped_type() ) )->m_value.second; \ } \ \ const_iterator find( const const_key_type& key ) const \ { \ return const_iterator( GetNode( key ), this ); \ } \ \ iterator find( const const_key_type& key ) \ { \ return iterator( GetNode( key ), this ); \ } \ \ void insert( const value_type& v ) { (*this)[v.first] = v.second; } \ \ size_type erase( const key_type& k ) \ { return CLASSNAME##_wxImplementation_HashTable::erase( k ); } \ void erase( const iterator& it ) { erase( it->first ); } \ void erase( const const_iterator& it ) { erase( it->first ); } \ \ /* count() == 0 | 1 */ \ size_type count( const const_key_type& key ) \ { return GetNode( key ) ? 1 : 0; } \ } // these macros are to be used in the user code #define WX_DECLARE_HASH_MAP( KEY_T, VALUE_T, HASH_T, KEY_EQ_T, CLASSNAME) \ _WX_DECLARE_HASH_MAP( KEY_T, VALUE_T, HASH_T, KEY_EQ_T, CLASSNAME, class ) #define WX_DECLARE_STRING_HASH_MAP( VALUE_T, CLASSNAME ) \ _WX_DECLARE_HASH_MAP( wxString, VALUE_T, wxStringHash, wxStringEqual, \ CLASSNAME, class ) #define WX_DECLARE_VOIDPTR_HASH_MAP( VALUE_T, CLASSNAME ) \ _WX_DECLARE_HASH_MAP( void*, VALUE_T, wxPointerHash, wxPointerEqual, \ CLASSNAME, class ) // and these do exactly the same thing but should be used inside the // library #define WX_DECLARE_HASH_MAP_WITH_DECL( KEY_T, VALUE_T, HASH_T, KEY_EQ_T, CLASSNAME, DECL) \ _WX_DECLARE_HASH_MAP( KEY_T, VALUE_T, HASH_T, KEY_EQ_T, CLASSNAME, DECL ) #define WX_DECLARE_EXPORTED_HASH_MAP( KEY_T, VALUE_T, HASH_T, KEY_EQ_T, CLASSNAME) \ WX_DECLARE_HASH_MAP_WITH_DECL( KEY_T, VALUE_T, HASH_T, KEY_EQ_T, \ CLASSNAME, class WXDLLEXPORT ) #define WX_DECLARE_STRING_HASH_MAP_WITH_DECL( VALUE_T, CLASSNAME, DECL ) \ _WX_DECLARE_HASH_MAP( wxString, VALUE_T, wxStringHash, wxStringEqual, \ CLASSNAME, DECL ) #define WX_DECLARE_EXPORTED_STRING_HASH_MAP( VALUE_T, CLASSNAME ) \ WX_DECLARE_STRING_HASH_MAP_WITH_DECL( VALUE_T, CLASSNAME, \ class WXDLLEXPORT ) #define WX_DECLARE_VOIDPTR_HASH_MAP_WITH_DECL( VALUE_T, CLASSNAME, DECL ) \ _WX_DECLARE_HASH_MAP( void*, VALUE_T, wxPointerHash, wxPointerEqual, \ CLASSNAME, DECL ) #define WX_DECLARE_EXPORTED_VOIDPTR_HASH_MAP( VALUE_T, CLASSNAME ) \ WX_DECLARE_VOIDPTR_HASH_MAP_WITH_DECL( VALUE_T, CLASSNAME, \ class WXDLLEXPORT ) // delete all hash elements // // NB: the class declaration of the hash elements must be visible from the // place where you use this macro, otherwise the proper destructor may not // be called (a decent compiler should give a warning about it, but don't // count on it)! #define WX_CLEAR_HASH_MAP(type, hashmap) \ { \ type::iterator it, en; \ for( it = (hashmap).begin(), en = (hashmap).end(); it != en; ++it ) \ delete it->second; \ (hashmap).clear(); \ } #endif // _WX_HASHMAP_H_