skcblitz/map.h

#define HASHM_BUCKETS 2

uint map_f_inthash(void *ptr) {
	uint hash = (uint)((ulong)ptr);
	return ((hash << 8) & 0xf000) | ((hash >> 8) & 0x0fff); // (hash >> 24) | ((hash >> 8) & 0x0000ff00) | ((hash << 8) & 0x00ff0000) | (hash << 24);
}

byte map_f_inteq(void *ptr1, void *ptr2) {
	return ptr1 == ptr2;
}

uint map_f_strhash(void *str) {
	int pos = 0;
	uint hash = 0;
	uint c;
	while(c = (uint)(((char*)str)[pos++])) {
		hash = 31 * hash + c;
	}
	return hash;
}

byte map_f_streq(void *str1, void *str2) {
	return strcmp((char*)str1, (char*)str2) == 0;
}

void map_init(map_t *map, map_hashfunc *hash, map_eqfunc *eq, uint load, byte cat) {
	map->hash_func = hash;
	map->eq_func = eq;
	map->elems = NULL;
	map->load = load;
	map->cat = cat;
	map->stored = 0;
}

/*
void **map_talloc(void ***ptr, byte offset) {
	void **list = *ptr;
	if(list == NULL) {
		*ptr = list = mem_alloc(sizeof(void **) * 256);
		memset(list, 0, sizeof(void **) * 256);
	}
	return list[offset];
}
*/

byte map_put(map_t *map, void *key, void *elem) {
	uint hash = map->hash_func(key);
	uint offset;
	uint size;
	void ***ptr = &map->elems;
	void **list = *ptr;
	void **elems;
	uint stored;
	for(int z = HASHM_BUCKETS - 1; z >= 0; z--) {
		offset = (hash >> (z << 3)) & 0xff;
		// list = *ptr;
		if(list == NULL) {
			*ptr = list = mem_alloc(sizeof(void **) * 256, map->cat);
			memset(list, 0, sizeof(void **) * 256);
		}
		ptr = (void***)&list[offset];
		list = list[offset];
	}
	if(list == NULL) {
		*ptr = list = mem_alloc(sizeof(void *) * map->load * 2 + sizeof(uint) * 2, map->cat);
		memset(list, 0, sizeof(void *) * map->load * 2 + sizeof(uint) * 2);
		((uint*)list)[0] = size = map->load;
		stored = 0;
	}
	else {
		size = ((uint*)list)[0];
		stored = ((uint*)list)[1];
	}
	elems = (void**)(((uint*)list) + 2);
	for(uint z = 0; z < size; z++) {
		if((elems[z*2] != NULL) && map->eq_func(key, elems[z*2])) {
			elems[z*2+0] = key;
			elems[z*2+1] = elem;
			return 0;
		}
	}
	if(stored == size) {
		*ptr = list = mem_realloc(list, sizeof(void *) * (size+(map->load)) * 2 + sizeof(uint) * 2, map->cat);
		elems = (void**)(((uint*)list) + 2);
		memset(&elems[size*2], 0, sizeof(void *) * map->load * 2); // + sizeof(uint) * 2);
		((uint*)list)[0] = size += map->load;
	}
	for(uint z = 0; z < size; z++) {
		if(elems[z*2] == NULL) {
			elems[z*2+0] = key;
			elems[z*2+1] = elem;
			break;
		}
	}
	((uint*)list)[1] = stored + 1;
	map->stored += 1;
	return 1;
}

void *map_get(map_t *map, void *key) {
	uint hash = map->hash_func(key);
	uint offset;
	uint size;
	void **list = map->elems;
	void **elems;
	for(int z = HASHM_BUCKETS - 1; z >= 0; z--) {
		if(list == NULL) {
			return NULL;
		}
		offset = (hash >> (z << 3)) & 0xff;
		list = list[offset];
	}
	if(list == NULL) {
		return NULL;
	}
	size = ((uint*)list)[0];
	elems = (void**)(((uint*)list) + 2);
	for(uint z = 0; z < size; z++) {
		if((elems[z*2] != NULL) && map->eq_func(key, elems[z*2+0])) {
			return elems[z*2+1];
		}
	}
	return NULL;
}

void *map_remove(map_t *map, void *key) {
	uint hash = map->hash_func(key);
	uint offset;
	uint size;
	uint stored;
	void **lists[HASHM_BUCKETS];
	void **list = map->elems;
	void **elems;
	void *elem;
	int s;
	for(int z = HASHM_BUCKETS - 1; z >= 0; z--) {
		if(list == NULL) {
			return NULL;
		}
		offset = (hash >> (z << 3)) & 0xff;
		lists[z] = list;
		list = list[offset];
	}
	size = ((uint*)list)[0];
	stored = ((uint*)list)[1];
	elems = (void**)(((uint*)list) + 2);
	for(uint z = 0; z < size; z++) {
		if((elems[z*2] != NULL) && map->eq_func(key, elems[z*2+0])) {
			elem = elems[z*2+1];
			elems[z*2+0] = elems[z*2+1] = NULL;
			((uint*)list)[1] = stored -= 1;
			// logd("t", "s %d", stored);
			if(stored == 0) {
				mem_free(list);
				for(int n = 0; n < HASHM_BUCKETS; n++) {
					// if(lists[n] == NULL) {
					// 	break;
					// }
					lists[n][(hash >> (n << 3)) & 0xff] = NULL;
					for(s = 0; s < 256; s++) {
						if(lists[n][s] != NULL) {
							break;
						}
					}
					if(s == 256) {
						mem_free(lists[n]);
						if(n == HASHM_BUCKETS - 1) {
							map->elems = NULL;
						}
						else {
							lists[n+1][(hash >> ((n+1) << 3)) & 0xff] = NULL;
						}
					}
					else {
						break;
					}
				}
			}
			map->stored -= 1;
			return elem;
		}
	}
	return NULL;
}

void map_rclear(void **list, int depth) {
	for(int z = 0; z < 256 && depth < HASHM_BUCKETS; z++) {
		if(list[z] != NULL) {
			map_rclear(list[z], depth+1);
		}
	}
	mem_free(list);
}

void map_clear(map_t *map) {
	map->stored = 0;
	if(map->elems)
		map_rclear(map->elems, 0);
	map->elems = NULL;
}