tab.c

   1 #include <stdlib.h>
   2 #include <string.h>
   3 #include "tab.h"
   4
   5 struct tab {
   6         char **keys;
   7         void **vals;
   8         int n;
   9         int *next;
  10         int head[256];
  11 };
  12
  13 struct tab *tab_alloc(int sz)
  14 {
  15         struct tab *tab = malloc(sizeof(*tab));
  16         int i;
  17         memset(tab, 0, sizeof(*tab));
  18         tab->keys = malloc(sz * sizeof(tab->keys[0]));
  19         tab->vals = malloc(sz * sizeof(tab->vals[0]));
  20         tab->next = malloc(sz * sizeof(tab->next[0]));
  21         for (i = 0; i < 256; i++)
  22                 tab->head[i] = -1;
  23         return tab;
  24 }
  25
  26 void tab_free(struct tab *tab)
  27 {
  28         free(tab->keys);
  29         free(tab->vals);
  30         free(tab->next);
  31         free(tab);
  32 }
  33
  34 void tab_put(struct tab *tab, char *k, void *v)
  35 {
  36         tab->keys[tab->n] = k;
  37         tab->vals[tab->n] = v;
  38         tab->next[tab->n] = tab->head[(unsigned char) k[0]];
  39         tab->head[(unsigned char) k[0]] = tab->n;
  40         tab->n++;
  41 }
  42
  43 void *tab_get(struct tab *tab, char *k)
  44 {
  45         int i = tab->head[(unsigned char) k[0]];
  46         while (i >= 0) {
  47                 if (k[1] == tab->keys[i][1] && !strcmp(k, tab->keys[i]))
  48                         return tab->vals[i];
  49                 i = tab->next[i];
  50         }
  51         return NULL;
  52 }