Re: [9fans] tcp!

[erik quanstrom <quanstro@quanstro.net>]

> - add support for new reno,

i apoligize for not mentioning that the new reno work
was part of the nix/9k tcp.  i'm not sure who wrote it.

sorry!

also i forgot to mention that this version of qread can
potentially cut the number of reads on tcp channels by up
to 1/2.  one might as well completely satisfy the read,
if possible.  especially since typical iounits (8192) do not
divide up into typical mss-sized (1460) packets evenly.

[...]
	/* if we get here, there's at least one block in the queue */
	if(q->state & Qcoalesce){
		/* when coalescing, 0 length blocks just go away */
		b = q->bfirst;
		if(BLEN(b) <= 0){
			freeb(qremove(q));
			goto again;
		}

		/*
		 * grab the first block and as many following
		 * blocks as will partially fit in the read
		 */
		n = 0;
		l = &first;
		for(;;) {
			*l = qremove(q);
			l = &b->next;
			n += BLEN(b);
			if(n >= len || (b = q->bfirst) == nil)
				break;
		}

- erik