Fumofumotris/source/fumoengine/include/dictionary.c
2024-05-15 17:10:47 -05:00

98 lines
2.1 KiB
C

#include "dictionary.h"
#include <stdalign.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
bool CreateDictionary(struct Dictionary *dict, usize value_size)
{
void *bkts = calloc(16, value_size);
if (bkts == nullptr)
return false;
dict->value_size = value_size;
dict->value_offset = max(alignof(u32), alignof(u8[dict->value_size]));
dict->bkt_size = dict->value_offset + value_size;
dict->filled = 0;
dict->capacity = 16;
dict->bkts = bkts;
return true;
}
void FreeDictionary(struct Dictionary *dict)
{
free(dict->bkts);
}
void *index_bkt(struct Dictionary *dict, usize i)
{
return (u8 *)dict->bkts + i * dict->bkt_size;
}
u32 *get_key(struct Dictionary *dict, void *bkt)
{
return (u32 *)bkt;
}
void *get_value_ptr(struct Dictionary *dict, void *bkt)
{
return (u8 *)bkt + dict->value_offset;
}
void set_bkt(struct Dictionary *dict, void *bkt, u32 key, void *value_ptr)
{
*get_key(dict, bkt) = key;
memcpy(get_value_ptr(dict, bkt), value_ptr, dict->value_size);
}
void *probe_bkt(struct Dictionary *dict, usize index, u32 key)
{
for (usize i = 0; i < dict->capacity; i++) {
void *bkt = index_bkt(dict, (index + i) % dict->capacity);
if (*get_key(dict, bkt) == key)
return bkt;
}
return nullptr;
}
void *probe_empty_bkt(struct Dictionary *dict, usize index, u32 key)
{
for (usize i = 0; i < dict->capacity; i++) {
void *bkt = index_bkt(dict, (index + i) % dict->capacity);
u32 k = *get_key(dict, bkt);
if (k == 0 or k == key)
return bkt;
}
return nullptr;
}
void *DictionaryFind(struct Dictionary *dict, u32 key)
{
usize index = key % dict->capacity;
void *bkt = probe_bkt(dict, index, key);
if (bkt == nullptr)
return false;
return get_value_ptr(dict, bkt);
}
void *DictionarySet(struct Dictionary *dict, u32 key, void *value_ptr)
{
usize index = key % dict->capacity;
void *bkt = probe_empty_bkt(dict, index, key);
if (*get_key(dict, bkt) == 0)
set_bkt(dict, bkt, key, value_ptr);
return bkt;
}