Function tcp_log_set_id

freebsd/netinet/tcp_log_buf.c:560–911

* Set the TCP log ID for a TCPCB. * Called with INPCB locked. Returns with it unlocked. */

 * Called with INPCB locked. Returns with it unlocked.
 */
int
tcp_log_set_id(struct tcpcb *tp, char *id)
{
	struct tcp_log_id_bucket *tlb, *tmp_tlb;
	struct tcp_log_id_node *tln;
	struct inpcb *inp;
	int tree_locked, rv;
	bool bucket_locked;

	tlb = NULL;
	tln = NULL;
	inp = tp->t_inpcb;
	tree_locked = TREE_UNLOCKED;
	bucket_locked = false;

restart:
	INP_WLOCK_ASSERT(inp);

	/* See if the ID is unchanged. */
	if ((tp->t_lib != NULL && !strcmp(tp->t_lib->tlb_id, id)) ||
	    (tp->t_lib == NULL && *id == 0)) {
		if (tp->t_lib != NULL) {
			tcp_log_increment_reqcnt(tp->t_lib);
			if ((tp->t_lib->tlb_logstate) &&
			    (tp->t_log_state_set == 0)) {
				/* Clone in any logging */

				tp->t_logstate = tp->t_lib->tlb_logstate;
			}
			if ((tp->t_lib->tlb_loglimit) &&
			    (tp->t_log_state_set == 0)) {
				/* We also have a limit set */

				tp->t_loglimit = tp->t_lib->tlb_loglimit;
			}
		}
		rv = 0;
		goto done;
	}

	/*
	 * If the TCPCB had a previous ID, we need to extricate it from
	 * the previous list.
	 *
	 * Drop the TCPCB lock and lock the tree and the bucket.
	 * Because this is called in the socket context, we (theoretically)
	 * don't need to worry about the INPCB completely going away
	 * while we are gone.
	 */
	if (tp->t_lib != NULL) {
		tlb = tp->t_lib;
		TCPID_BUCKET_REF(tlb);
		INP_WUNLOCK(inp);

		if (tree_locked == TREE_UNLOCKED) {
			TCPID_TREE_RLOCK();
			tree_locked = TREE_RLOCKED;
		}