Annotation of parser3/src/include/pa_hash.h, revision 1.57
1.28 paf 1: /** @file
1.29 paf 2: Parser: hash class decl.
3:
1.53 paf 4: Copyright (c) 2001, 2002 ArtLebedev Group (http://www.artlebedev.com)
1.29 paf 5:
1.54 paf 6: Author: Alexandr Petrosian <paf@design.ru> (http://paf.design.ru)
1.1 paf 7: */
8:
9: #ifndef PA_HASH_H
10: #define PA_HASH_H
1.56 paf 11:
1.57 ! paf 12: static const char* IDENT_HASH_H="$Date: pa_hash.h,v 1.56 2002/08/01 11:26:47 paf Exp $";
1.1 paf 13:
1.14 paf 14: #include "pa_pool.h"
1.1 paf 15: #include "pa_types.h"
16: #include "pa_string.h"
17:
1.29 paf 18: /**
19: Pooled hash.
20:
21: Automatically rehashed when almost full.
1.51 paf 22: Contains no 0 values.
23: get returning 0 means there were no such.
24: "put value 0" means "remove"
1.29 paf 25: */
1.23 paf 26: class Hash : public Pooled {
1.1 paf 27: public:
28:
1.29 paf 29: typedef String Key; ///< hash Key type. longing for templates
1.30 paf 30: typedef void Val; ///< hash Val type. longing for templates
1.3 paf 31:
1.31 paf 32: /// for_each iterator function type
33: typedef void (*For_each_func)(const Key& key, Val *value, void *info);
1.25 paf 34:
1.45 paf 35: /// for_each iterator function type
36: typedef void (*For_each_func_refed)(const Key& key, Val *& value, void *info);
37:
1.38 paf 38: /// first_that iterator function type
1.42 parser 39: typedef void *(*First_that_func)(const Key& key, Val *value, void *info);
1.38 paf 40:
1.8 paf 41: public:
42:
1.35 paf 43: Hash(Pool& apool) : Pooled(apool) {
1.43 parser 44: construct_new();
45: }
46:
47: Hash(const Hash& source) : Pooled(source.pool()){
48: construct_copy(source);
1.24 paf 49: }
1.10 paf 50:
1.29 paf 51: /// useful generic hash function
1.19 paf 52: static uint generic_code(uint aresult, const char *start, uint allocated);
1.8 paf 53:
1.51 paf 54: /// put a [value] under the [key] @returns existed or not
1.40 parser 55: bool put(const Key& key, Val *value);
1.48 paf 56:
1.51 paf 57: /// remove the [key] @returns existed or not
58: bool remove(const Key& key);
1.33 paf 59: /*
60: /// dirty hack to allow constant items storage. I long for Hash<const Val*>
1.40 parser 61: bool put(const Key& key, const Val *value) {
1.33 paf 62: return put(key, const_cast<Val *>(value));
63: }
64: */
1.29 paf 65: /// get associated [value] by the [key]
1.40 parser 66: Val *get(const Key& key) const;
1.17 paf 67:
1.51 paf 68: /// put a [value] under the [key] if that [key] existed @returns existed or not
1.40 parser 69: bool put_replace(const Key& key, Val *value);
1.18 paf 70:
1.51 paf 71: /// put a [value] under the [key] if that [key] NOT existed @returns existed or not
1.40 parser 72: bool put_dont_replace(const Key& key, Val *value);
1.18 paf 73:
1.29 paf 74: /// put all 'src' values if NO with same key existed
1.40 parser 75: void merge_dont_replace(const Hash& src);
1.11 paf 76:
1.30 paf 77: void put(const Key& key, int value) { put(key, reinterpret_cast<Val *>(value)); }
1.36 paf 78: void put(const Key& key, const String *value) {
79: put(key, static_cast<Val *>(const_cast<String *>(value)));
80: }
1.11 paf 81:
1.29 paf 82: //@{
83: /// handy get, longing for Hash<int>, Hash<String *>
1.32 paf 84: int get_int(const Key& key) const { return reinterpret_cast<int>(get(key)); }
85: const String *get_string(const Key& key) const { return static_cast<String *>(get(key)); }
1.29 paf 86: //@}
1.10 paf 87:
1.29 paf 88: /// number of elements in hash
1.44 parser 89: int size() const { return count; }
1.25 paf 90:
1.29 paf 91: /// iterate over all not zero elements
1.36 paf 92: void for_each(For_each_func func, void *info=0) const;
1.45 paf 93:
94: /// iterate over all not zero elements, passing references
95: void for_each(For_each_func_refed func, void *info=0) const;
1.38 paf 96:
97: /// iterate over all elements until condition
1.42 parser 98: void *first_that(First_that_func func, void *info=0) const;
1.27 paf 99:
1.29 paf 100: /// remove all elements
1.27 paf 101: void clear();
1.19 paf 102:
1.15 paf 103: protected:
104:
1.43 parser 105: void construct_new();
106: void construct_copy(const Hash& source);
1.15 paf 107:
1.1 paf 108: private:
109:
1.39 paf 110: /// expand when these %% of allocated exausted
1.1 paf 111: enum {
112: THRESHOLD_PERCENT=75
113: };
1.9 paf 114:
1.39 paf 115: /// the index of [allocated] in [allocates]
1.19 paf 116: int allocates_index;
1.1 paf 117:
1.39 paf 118: /// possible [allocates]. prime numbers
1.19 paf 119: static uint allocates[];
120: static int allocates_count;
1.1 paf 121:
1.39 paf 122: /// number of allocated pairs
1.19 paf 123: int allocated;
1.1 paf 124:
1.39 paf 125: /// helper: expanding when used == threshold
1.1 paf 126: int threshold;
127:
1.39 paf 128: /// used pairs
1.1 paf 129: int used;
1.44 parser 130:
131: /// stored pairs total (including those by links)
132: int count;
1.1 paf 133:
1.39 paf 134: /// pair storage
1.1 paf 135: class Pair {
1.46 paf 136: friend class Hash;
1.2 paf 137:
1.1 paf 138: uint code;
1.47 paf 139: const Key& key;
1.30 paf 140: Val *value;
1.1 paf 141: Pair *link;
1.2 paf 142:
1.19 paf 143: void *operator new(size_t allocated, Pool& apool);
1.2 paf 144:
1.30 paf 145: Pair(uint acode, const Key& akey, Val *avalue, Pair *alink) :
1.1 paf 146: code(acode),
147: key(akey),
148: value(avalue),
1.2 paf 149: link(alink) {}
150: } **refs;
1.1 paf 151:
1.39 paf 152: /// filled to threshold: needs expanding
1.5 paf 153: bool full() { return used==threshold; }
154:
1.39 paf 155: /// allocate larger buffer & rehash
1.1 paf 156: void expand();
1.4 paf 157:
158: private: //disabled
159:
1.12 paf 160: Hash& operator = (const Hash&) { return *this; }
1.1 paf 161: };
1.49 paf 162:
1.55 paf 163: /// Auto-object used for temporarily substituting/removing hash values
164: class Temp_hash_value {
165: Hash& fhash;
166: const Hash::Key& fname;
167: Hash::Val *saved_value;
168: public:
169: Temp_hash_value(Hash& ahash, const Hash::Key& aname, Hash::Val *avalue) :
170: fhash(ahash),
171: fname(aname),
172: saved_value(ahash.get(aname)) {
173: fhash.put(aname, avalue);
174: }
175: ~Temp_hash_value() {
176: fhash.put(fname, saved_value);
177: }
178: };
1.1 paf 179:
180: #endif
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