[17930] | 1 | /** \ingroup python |
---|
| 2 | * \file python/hash.c |
---|
| 3 | */ |
---|
| 4 | |
---|
| 5 | #include <stdlib.h> |
---|
| 6 | #include <unistd.h> |
---|
| 7 | #include <stdio.h> |
---|
| 8 | #include <string.h> |
---|
| 9 | |
---|
| 10 | #include "hash.h" |
---|
| 11 | |
---|
| 12 | #define CHUNK 1 |
---|
| 13 | |
---|
| 14 | struct filePath { |
---|
| 15 | char * dir; |
---|
| 16 | char * base; |
---|
| 17 | } ; |
---|
| 18 | |
---|
| 19 | struct bucket { |
---|
| 20 | struct filePath * data; |
---|
| 21 | int allocated; |
---|
| 22 | int firstFree; /* as in data[firstFree] */ |
---|
| 23 | }; |
---|
| 24 | |
---|
| 25 | struct hash_table { |
---|
| 26 | int size; |
---|
| 27 | int entries; |
---|
| 28 | int overHead; |
---|
| 29 | struct bucket *bucket; |
---|
| 30 | }; |
---|
| 31 | |
---|
| 32 | struct hash_table *htNewTable(int size) |
---|
| 33 | { |
---|
| 34 | struct hash_table *res; |
---|
| 35 | int i = 0; |
---|
| 36 | |
---|
| 37 | res = malloc(sizeof(struct hash_table)); |
---|
| 38 | res->bucket = malloc(sizeof(struct bucket) * size); |
---|
| 39 | res->size = size; |
---|
| 40 | res->entries = 0; |
---|
| 41 | res->overHead = sizeof(struct bucket) * size + CHUNK * sizeof(char *); |
---|
| 42 | |
---|
| 43 | while (i < size) { |
---|
| 44 | res->bucket[i].data = malloc(CHUNK * sizeof(*res->bucket[i].data)); |
---|
| 45 | res->bucket[i].allocated = CHUNK; |
---|
| 46 | res->bucket[i].firstFree = 0; |
---|
| 47 | i++; |
---|
| 48 | } |
---|
| 49 | |
---|
| 50 | return res; |
---|
| 51 | } |
---|
| 52 | |
---|
| 53 | void htFreeHashTable(struct hash_table *ht) |
---|
| 54 | { |
---|
| 55 | struct bucket * b; |
---|
| 56 | int item; |
---|
| 57 | |
---|
| 58 | b = ht->bucket; |
---|
| 59 | while (ht->size--) { |
---|
| 60 | for (item = 0; item < b->firstFree; item++) { |
---|
| 61 | free(b->data[item].dir); |
---|
| 62 | free(b->data[item].base); |
---|
| 63 | } |
---|
| 64 | free(b->data); |
---|
| 65 | b++; |
---|
| 66 | } |
---|
| 67 | free(ht->bucket); |
---|
| 68 | free(ht); |
---|
| 69 | } |
---|
| 70 | |
---|
| 71 | void htHashStats(const struct hash_table *t) |
---|
| 72 | { |
---|
| 73 | int i = 0; |
---|
| 74 | int empty = 0; |
---|
| 75 | |
---|
| 76 | while (i < t->size) { |
---|
| 77 | if (t->bucket[i].firstFree != 0) { |
---|
| 78 | /*printf("Bucket %d used %d\n", i, t->bucket[i].firstFree);*/ |
---|
| 79 | } else { |
---|
| 80 | empty++; |
---|
| 81 | } |
---|
| 82 | i++; |
---|
| 83 | } |
---|
| 84 | |
---|
| 85 | printf("Total Buckets : %d\n", t->size); |
---|
| 86 | printf("Empty Buckets : %d\n", empty); |
---|
| 87 | printf("Total Entries : %d\n", t->entries); |
---|
| 88 | printf("Total Overhead: %d\n", t->overHead); |
---|
| 89 | printf("Avergage Depth: %f\n", (double)t->entries / (double)t->size); |
---|
| 90 | } |
---|
| 91 | |
---|
| 92 | static unsigned int htHashStrings(const char * s, const char * t) |
---|
| 93 | { |
---|
| 94 | unsigned int res = 0; |
---|
| 95 | |
---|
| 96 | while (*s != '\0') |
---|
| 97 | res = ((res<<1) + (int)(*(s++))); |
---|
| 98 | while (*t != '\0') |
---|
| 99 | res = ((res<<1) + (int)(*(t++))); |
---|
| 100 | |
---|
| 101 | return res; |
---|
| 102 | } |
---|
| 103 | |
---|
| 104 | /* returns bucket # containing item, or -1 */ |
---|
| 105 | static int in_table_aux(struct hash_table *t, int hash, const char * dir, |
---|
| 106 | const char * base) |
---|
| 107 | { |
---|
| 108 | int x; |
---|
| 109 | |
---|
| 110 | x = 0; |
---|
| 111 | while (x < t->bucket[hash].firstFree) { |
---|
| 112 | if (! strcmp(t->bucket[hash].data[x].dir, dir) && |
---|
| 113 | ! strcmp(t->bucket[hash].data[x].base, base)) { |
---|
| 114 | return x; |
---|
| 115 | } |
---|
| 116 | x++; |
---|
| 117 | } |
---|
| 118 | |
---|
| 119 | return -1; |
---|
| 120 | } |
---|
| 121 | |
---|
| 122 | int htInTable(struct hash_table *t, const char * dir, const char * base) |
---|
| 123 | { |
---|
| 124 | int hash; |
---|
| 125 | |
---|
| 126 | hash = htHashStrings(dir, base) % t->size; |
---|
| 127 | |
---|
| 128 | if (in_table_aux(t, hash, dir, base) == -1) |
---|
| 129 | return 0; |
---|
| 130 | return 1; |
---|
| 131 | } |
---|
| 132 | |
---|
| 133 | void htAddToTable(struct hash_table *t, const char * dir, const char * base) |
---|
| 134 | { |
---|
| 135 | static int hash = 1; |
---|
| 136 | |
---|
| 137 | if (!dir || !base) |
---|
| 138 | return; |
---|
| 139 | |
---|
| 140 | hash = htHashStrings(dir, base) % t->size; |
---|
| 141 | if (in_table_aux(t, hash, dir, base) != -1) |
---|
| 142 | return; |
---|
| 143 | |
---|
| 144 | if (t->bucket[hash].firstFree == t->bucket[hash].allocated) { |
---|
| 145 | t->bucket[hash].allocated += CHUNK; |
---|
| 146 | t->bucket[hash].data = |
---|
| 147 | realloc(t->bucket[hash].data, |
---|
| 148 | t->bucket[hash].allocated * sizeof(*(t->bucket->data))); |
---|
| 149 | /*printf("Bucket %d grew to %d\n", hash, t->bucket[hash].allocated);*/ |
---|
| 150 | t->overHead += sizeof(char *) * CHUNK; |
---|
| 151 | } |
---|
| 152 | /*printf("In bucket %d, item %d\n", hash, t->bucket[hash].firstFree);*/ |
---|
| 153 | t->bucket[hash].data[t->bucket[hash].firstFree].dir = strdup(dir); |
---|
| 154 | t->bucket[hash].data[t->bucket[hash].firstFree++].base = strdup(base); |
---|
| 155 | t->entries++; |
---|
| 156 | } |
---|
| 157 | |
---|
| 158 | void htRemoveFromTable(struct hash_table *t, const char * dir, |
---|
| 159 | const char * base) { |
---|
| 160 | int hash; |
---|
| 161 | int item; |
---|
| 162 | int last; |
---|
| 163 | |
---|
| 164 | hash = htHashStrings(dir, base) % t->size; |
---|
| 165 | if ((item = in_table_aux(t, hash, dir, base)) == -1) { |
---|
| 166 | return; |
---|
| 167 | } |
---|
| 168 | |
---|
| 169 | free(t->bucket[hash].data[item].dir); |
---|
| 170 | free(t->bucket[hash].data[item].base); |
---|
| 171 | |
---|
| 172 | last = --t->bucket[hash].firstFree; |
---|
| 173 | t->bucket[hash].data[item] = t->bucket[hash].data[last]; |
---|
| 174 | } |
---|
| 175 | |
---|
| 176 | int htNumEntries(struct hash_table *t) { |
---|
| 177 | return t->entries; |
---|
| 178 | } |
---|
| 179 | |
---|
| 180 | void htIterStart(htIterator * iter) { |
---|
| 181 | iter->bucket = 0; |
---|
| 182 | iter->item = -1; |
---|
| 183 | } |
---|
| 184 | |
---|
| 185 | int htIterGetNext(struct hash_table * t, htIterator * iter, |
---|
| 186 | const char ** dir, const char ** base) { |
---|
| 187 | iter->item++; |
---|
| 188 | |
---|
| 189 | while (iter->bucket < t->size) { |
---|
| 190 | if (iter->item < t->bucket[iter->bucket].firstFree) { |
---|
| 191 | *dir = t->bucket[iter->bucket].data[iter->item].dir; |
---|
| 192 | *base = t->bucket[iter->bucket].data[iter->item].base; |
---|
| 193 | |
---|
| 194 | return 1; |
---|
| 195 | } |
---|
| 196 | |
---|
| 197 | iter->item++; |
---|
| 198 | if (iter->item >= t->bucket[iter->bucket].firstFree) { |
---|
| 199 | iter->bucket++; |
---|
| 200 | iter->item = 0; |
---|
| 201 | } |
---|
| 202 | } |
---|
| 203 | |
---|
| 204 | return 0; |
---|
| 205 | } |
---|