Annotation of parser3/src/include/pa_hash.h, revision 1.17
1.1 paf 1: /*
1.17 ! paf 2: $Id: pa_hash.h,v 1.16 2001/02/22 16:21:48 paf Exp $
1.1 paf 3: */
4:
5: /*
6:
7:
8: */
9:
10: #ifndef PA_HASH_H
11: #define PA_HASH_H
12:
13: #include <stddef.h>
14:
1.14 paf 15: #include "pa_pool.h"
1.1 paf 16: #include "pa_types.h"
17: #include "pa_string.h"
18:
1.16 paf 19: class Hash : virtual public Pooled {
1.1 paf 20: public:
21:
1.3 paf 22: typedef String Key;
23: typedef void Value;
24:
1.8 paf 25: public:
26:
1.15 paf 27: Hash(Pool& apool,bool) : Pooled(apool) { construct(apool, true); }
28: Hash(Pool& apool) : Pooled(apool) { construct(apool, false); }
1.10 paf 29:
1.8 paf 30: // useful generic hash function
1.12 paf 31: static uint generic_code(uint aresult, const char *start, uint size);
1.8 paf 32:
33: // put a [value] under the [key]
1.13 paf 34: /*SYNCHRONIZED*/ void put(const Key& key, Value *value);
1.8 paf 35:
36: // get associated [value] by the [key]
1.15 paf 37: /*SYNCHRONIZED*/ Value *get(const Key& key) const;
1.17 ! paf 38:
! 39: // put a [value] under the [key] if that [key] existed, return existed or not
! 40: /*SYNCHRONIZED*/ bool replace(const Key& key, Value *value);
1.11 paf 41:
1.13 paf 42: void put(const Key& key, int value) { put(key, reinterpret_cast<Value *>(value)); }
43: void put(const Key& key, String *value) { put(key, static_cast<Value *>(value)); }
1.11 paf 44:
1.13 paf 45: int get_int(const Key& key) { return reinterpret_cast<int>(get(key)); }
46: String *get_string(const Key& key) { return static_cast<String *>(get(key)); }
1.10 paf 47:
1.15 paf 48: protected:
49:
50: void construct(Pool& apool, bool athread_safe);
51:
1.1 paf 52: private:
53:
1.6 paf 54: // expand when these %% of size exausted
1.1 paf 55: enum {
56: THRESHOLD_PERCENT=75
57: };
58:
1.9 paf 59: // am I thread-safe?
60: bool thread_safe;
61:
1.5 paf 62: // the index of [size] in [sizes]
1.1 paf 63: int size_index;
64:
1.5 paf 65: // possible [sizes]. prime numbers
1.1 paf 66: static uint sizes[];
67: static int sizes_count;
68:
69: // number of allocated pairs
70: int size;
71:
72: // helper: expanding when used == threshold
73: int threshold;
74:
75: // used pairs
76: int used;
77:
78: // main storage
79: class Pair {
1.2 paf 80: friend Hash;
81:
1.1 paf 82: uint code;
1.15 paf 83: const Key key;
1.1 paf 84: Value *value;
85: Pair *link;
1.2 paf 86:
1.11 paf 87: void *operator new(size_t size, Pool& apool);
1.2 paf 88:
1.13 paf 89: Pair(uint acode, const Key& akey, Value *avalue, Pair *alink) :
1.1 paf 90: code(acode),
91: key(akey),
92: value(avalue),
1.2 paf 93: link(alink) {}
94: } **refs;
1.1 paf 95:
1.5 paf 96: // filled to threshold: needs expanding
97: bool full() { return used==threshold; }
98:
99: // allocate larger buffer & rehash
1.1 paf 100: void expand();
1.4 paf 101:
102: private: //disabled
103:
1.11 paf 104: //Hash(Hash&) {}
1.12 paf 105: Hash& operator = (const Hash&) { return *this; }
1.1 paf 106: };
107:
108: #endif
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