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Code: Select all

void *kmalloc (uint32_t l)
{
	l += sizeof (header_t);

	header_t *cur_header = heap_first, *prev_header = 0;
	while (cur_header)
	{
		if (cur_header->allocated == 0 && cur_header->length >= l)
		{
			split_chunk (cur_header, l);
			cur_header->allocated = 1;
			return (void*) ((uint32_t)cur_header + sizeof (header_t));
		}
		prev_header = cur_header;
		cur_header = cur_header->next;
	}

	uint32_t chunk_start;
	if (prev_header) chunk_start = (uint32_t)prev_header + prev_header->length;
	else
	{
		chunk_start = HEAP_START;
		heap_first = (header_t *)chunk_start;
	}

	alloc_chunk (chunk_start, l);
	cur_header = (header_t *)chunk_start;
	cur_header->prev = prev_header;
	cur_header->next = 0;
	cur_header->allocated = 1;
	cur_header->length = l;

	prev_header->next = cur_header;

	return (void*) (chunk_start + sizeof (header_t));
}

Code: Select all

alloc_chunk (chunk_start, l);
	printf("It works!");
	cur_header = (header_t *)chunk_start;
	cur_header->prev = prev_header;
	cur_header->next = 0;
	cur_header->allocated = 1;
	cur_header->length = l;

Code: Select all

void alloc_chunk (uint32_t start, uint32_t len)
{
	while (start + len > heap_max)
	{
		uint32_t page = pmm_alloc_page ();
		map (heap_max, page, PAGE_PRESENT | PAGE_WRITE);
		heap_max += 0x1000;
	}
}