Function hp_malloc_init

mem/hp_malloc.c:530–590

initialise the allocator and return its main block */

/* initialise the allocator and return its main block */
static struct hp_block *hp_malloc_init(char *address, unsigned long size,
										char *name)
{
	char *start;
	char *end;
	struct hp_block *hpb;
	unsigned long init_overhead;

	/* make address and size multiple of 8*/
	start = (char *)ROUNDUP((unsigned long) address);
	LM_DBG("HP_OPTIMIZE=%lu, HP_LINEAR_HASH_SIZE=%lu, %lu-bytes aligned\n",
			HP_MALLOC_OPTIMIZE, HP_LINEAR_HASH_SIZE, (unsigned long)ROUNDTO);
	LM_DBG("HP_HASH_SIZE=%lu, HP_EXTRA_HASH_SIZE=%lu, hp_block size=%zu, "
			"frag_size=%zu\n", HP_HASH_SIZE, HP_EXTRA_HASH_SIZE,
			sizeof(struct hp_block), sizeof(struct hp_frag));
	LM_DBG("params (%p, %lu), start=%p\n", address, size, start);

	if (size < (unsigned long)(start - address))
		return NULL;

	size -= start - address;

	if (size < (MIN_FRAG_SIZE+FRAG_OVERHEAD))
		return NULL;

	size = ROUNDDOWN(size);

	init_overhead = ROUNDUP(sizeof(struct hp_block)) + 2 * FRAG_OVERHEAD;
	if (size < init_overhead)
	{
		LM_ERR("not enough memory for the basic structures! "
		       "need %lu bytes\n", init_overhead);
		/* not enough mem to create our control structures !!!*/
		return NULL;
	}

	end = start + size;
	hpb = (struct hp_block *)(void *)start;
	memset(hpb, 0, sizeof(struct hp_block));
	hpb->name = name;
	hpb->size = size;

	hpb->used = 0;
	hpb->real_used = init_overhead;
	hpb->max_real_used = init_overhead;
	hpb->total_fragments = 2;
	gettimeofday(&hpb->last_updated, NULL);

	hpb->first_frag = (struct hp_frag *)(void *)(start + ROUNDUP(sizeof(struct hp_block)));
	hpb->last_frag = (struct hp_frag *)(void *)end - 1;
	hpb->last_frag->size = 0;

	/* init initial fragment */
	hpb->first_frag->size = size - init_overhead;
	hpb->first_frag->prev = NULL;
	hpb->last_frag->prev  = NULL;

	hp_frag_attach(hpb, hpb->first_frag);