1/*
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24
25#ifndef SHARE_LIBADT_DICT_HPP
26#define SHARE_LIBADT_DICT_HPP
27
28// Dictionaries - An Abstract Data Type
29
30#include "memory/allocation.hpp"
31#include "memory/resourceArea.hpp"
32#include "runtime/thread.hpp"
33
34class Dict;
35
36// These dictionaries define a key-value mapping. They can be inserted to,
37// searched or deleted from. They grow and shrink as needed. The key is a
38// pointer to something (or anything which can be stored in a pointer). A
39// key comparison routine determines if two keys are equal or not. A hash
40// function can be provided; if it's not provided the key itself is used
41// instead. A nice string hash function is included.
42typedef int32_t (*CmpKey)(const void *key1, const void *key2);
43typedef int (*Hash)(const void *key);
44typedef void (*FuncDict)(const void *key, const void *val, Dict *d);
45
46class Dict : public ResourceObj { // Dictionary structure
47 private:
48 class Arena *_arena; // Where to draw storage from
49 class bucket *_bin; // Hash table is array of buckets
50 uint _size; // Size (# of slots) in hash table
51 uint32_t _cnt; // Number of key-value pairs in hash table
52 const Hash _hash; // Hashing function
53 const CmpKey _cmp; // Key comparison function
54 void doubhash( void ); // Double hash table size
55
56 public:
57 friend class DictI; // Friendly iterator function
58
59 // cmp is a key comparision routine. hash is a routine to hash a key.
60 Dict( CmpKey cmp, Hash hash );
61 Dict( CmpKey cmp, Hash hash, Arena *arena, int size=16 );
62 ~Dict();
63
64 Dict( const Dict & ); // Deep-copy guts
65 Dict &operator =( const Dict & );
66
67 // Zap to empty; ready for re-use
68 void Clear();
69
70 // Return # of key-value pairs in dict
71 uint32_t Size(void) const { return _cnt; }
72
73 // Insert inserts the given key-value pair into the dictionary. The prior
74 // value of the key is returned; NULL if the key was not previously defined.
75 void *Insert(void *key, void *val, bool replace = true); // A new key-value
76 void *Delete(void *key); // Delete & return old
77
78 // Find finds the value of a given key; or NULL if not found.
79 // The dictionary is NOT changed.
80 void *operator [](const void *key) const; // Do a lookup
81
82 // == compares two dictionaries; they must have the same keys (their keys
83 // must match using CmpKey) and they must have the same values (pointer
84 // comparison). If so 1 is returned, if not 0 is returned.
85 int32_t operator ==(const Dict &d) const; // Compare dictionaries for equal
86
87 // Print out the dictionary contents as key-value pairs
88 void print();
89};
90
91// Hashing functions
92int hashstr(const void *s); // Nice string hash
93// Slimey cheap hash function; no guaranteed performance. Better than the
94// default for pointers, especially on MS-DOS machines.
95int hashptr(const void *key);
96// Slimey cheap hash function; no guaranteed performance.
97int hashkey(const void *key);
98
99// Key comparators
100int32_t cmpstr(const void *k1, const void *k2);
101// Slimey cheap key comparator.
102int32_t cmpkey(const void *key1, const void *key2);
103
104//------------------------------Iteration--------------------------------------
105// The class of dictionary iterators. Fails in the presences of modifications
106// to the dictionary during iteration (including searches).
107// Usage: for( DictI i(dict); i.test(); ++i ) { body = i.key; body = i.value;}
108class DictI {
109 private:
110 const Dict *_d; // Dictionary being iterated over
111 uint _i; // Counter over the bins
112 uint _j; // Counter inside each bin
113 public:
114 const void *_key, *_value; // Easy access to the key-value pair
115 DictI( const Dict *d ) {reset(d);}; // Create a new iterator
116 void reset( const Dict *dict ); // Reset existing iterator
117 void operator ++(void); // Increment iterator
118 int test(void) { return _i<_d->_size;} // Test for end of iteration
119};
120
121#endif // SHARE_LIBADT_DICT_HPP
122