 /* Account for SACKS, we may need to fragment due to this. * It is just like the real MSS changing on us midstream. * We also handle things correctly when the user adds some * IP options mid-stream.  Silly to do, but cover it. */ mss_now = tcp_current_mss(sk, 1); 
static int tcp_write_xmit(struct sock *sk, int nonagle){	struct tcp_sock *tp = tcp_sk(sk);	struct sk_buff *skb;	unsigned int mss_now;	int sent_pkts;	/* If we are closed, the bytes will have to remain here.	 * In time closedown will finish, we empty the write queue and all	 * will be happy.	 */	if (unlikely(sk->sk_state == TCP_CLOSE))		return 0;	/* Account for SACKS, we may need to fragment due to this.	 * It is just like the real MSS changing on us midstream.	 * We also handle things correctly when the user adds some	 * IP options mid-stream.  Silly to do, but cover it.	 */	mss_now = tcp_current_mss(sk, 1);	sent_pkts = 0;	while ((skb = sk->sk_send_head) &&	       tcp_snd_test(sk, skb, mss_now,			    tcp_skb_is_last(sk, skb) ? nonagle :			    TCP_NAGLE_PUSH)) {		if (skb->len > mss_now) {			if (tcp_fragment(sk, skb, mss_now))				break;		}		TCP_SKB_CB(skb)->when = tcp_time_stamp;		tcp_tso_set_push(skb);		if (tcp_transmit_skb(sk, skb_clone(skb, GFP_ATOMIC)))			break;		/* Advance the send_head.  This one is sent out.		 * This call will increment packets_out.		 */		update_send_head(sk, tp, skb);		tcp_minshall_update(tp, mss_now, skb);		sent_pkts = 1;	}	if (sent_pkts) {		tcp_cwnd_validate(sk, tp);		return 0;	}	return !tp->packets_out && sk->sk_send_head;}
10457	/local/tlutelli/issta_data/temp/c/2005_temp/2005/10457/a2e2a59c93cc8ba39caa9011c2573f429e40ccd9/tcp_output.c/clean/net/ipv4/tcp_output.c