Function qm_malloc_init

mem/q_malloc.c:185–255

init malloc and return a qm_block*/

/* init malloc and return a qm_block*/
struct qm_block *qm_malloc_init(char *address, unsigned long size, char *name)
{
	char *start;
	char *end;
	struct qm_block *qm;
	unsigned long init_overhead;
	int h;

	/* make address and size multiple of 8*/
	start=(char*)ROUNDUP((unsigned long) address);
	LM_DBG("QM_OPTIMIZE=%lu, /ROUNDTO=%lu, %lu-bytes aligned\n",
			Q_MALLOC_OPTIMIZE, Q_MALLOC_OPTIMIZE/QM_ROUNDTO,
			(unsigned long)QM_ROUNDTO);
	LM_DBG("QM_HASH_SIZE=%lu, qm_block size=%zu, frag_size=%zu\n",
			QM_HASH_SIZE, sizeof(struct qm_block), FRAG_OVERHEAD);
	LM_DBG("params (%p, %lu), start=%p\n", address, size, start);
	if (size<start-address) return 0;
	size-=(start-address);
	if (size <(MIN_FRAG_SIZE+FRAG_OVERHEAD)) return 0;
	size=ROUNDDOWN(size);

	init_overhead=ROUNDUP(sizeof(struct qm_block))+sizeof(struct qm_frag)+
		sizeof(struct qm_frag_end);
	LM_DBG("size= %lu, init_overhead=%lu\n", size, init_overhead);

	if (size < init_overhead)
	{
		/* not enough mem to create our control structures !!!*/
		return 0;
	}
	end=start+size;
	qm=(struct qm_block*)(void *)start;
	memset(qm, 0, sizeof(struct qm_block));
	qm->name=name;
	qm->size=size;
	qm->used=size-init_overhead;
	qm->fragments = 0;

	qm->real_used=size;
	qm->max_real_used = 0;
	size-=init_overhead;

	qm->first_frag=(struct qm_frag*)(void *)(start+ROUNDUP(sizeof(struct qm_block)));
	qm->last_frag_end=(struct qm_frag_end*)(void *)end-1;
	/* init initial fragment*/
	qm->first_frag->size=size;
	qm->last_frag_end->size=size;

#ifdef DBG_MALLOC
	qm->first_frag->check=ST_CHECK_PATTERN;
	qm->last_frag_end->check1=END_CHECK_PATTERN1;
	qm->last_frag_end->check2=END_CHECK_PATTERN2;
#endif
	/* init free_hash* */
	for (h=0; h<QM_HASH_SIZE;h++){
		qm->free_hash[h].head.u.nxt_free=&(qm->free_hash[h].head);
		qm->free_hash[h].tail.prev_free=&(qm->free_hash[h].head);
		qm->free_hash[h].head.size=0;