/* This function is designed to be called from within the stream handler to
 * update the channels' expiration timers and the stream interface's flags
 * based on the channels' flags. It needs to be called only once after the
 * channels' flags have settled down, and before they are cleared, though it
 * doesn't harm to call it as often as desired (it just slightly hurts
 * performance). It must not be called from outside of the stream handler,
 * as what it does will be used to compute the stream task's expiration.
 */
void stream_int_update(struct stream_interface *si)
{
	struct channel *ic = si_ic(si);
	struct channel *oc = si_oc(si);

	if (!(ic->flags & CF_SHUTR)) {
		/* Read not closed, update FD status and timeout for reads */
		if ((ic->flags & CF_DONT_READ) || !channel_may_recv(ic)) {
			/* stop reading */
			if (!(si->flags & SI_FL_WAIT_ROOM)) {
				if (!(ic->flags & CF_DONT_READ)) /* full */
					si->flags |= SI_FL_WAIT_ROOM;
				ic->rex = TICK_ETERNITY;
			}
		}
		else {
			/* (re)start reading and update timeout. Note: we don't recompute the timeout
			 * everytime we get here, otherwise it would risk never to expire. We only
			 * update it if is was not yet set. The stream socket handler will already
			 * have updated it if there has been a completed I/O.
			 */
			si->flags &= ~SI_FL_WAIT_ROOM;
			if (!(ic->flags & (CF_READ_NOEXP|CF_DONT_READ)) && !tick_isset(ic->rex))
				ic->rex = tick_add_ifset(now_ms, ic->rto);
		}
	}

	if (!(oc->flags & CF_SHUTW)) {
		/* Write not closed, update FD status and timeout for writes */
		if (channel_is_empty(oc)) {
			/* stop writing */
			if (!(si->flags & SI_FL_WAIT_DATA)) {
				if ((oc->flags & CF_SHUTW_NOW) == 0)
					si->flags |= SI_FL_WAIT_DATA;
				oc->wex = TICK_ETERNITY;
			}
		}
		else {
			/* (re)start writing and update timeout. Note: we don't recompute the timeout
			 * everytime we get here, otherwise it would risk never to expire. We only
			 * update it if is was not yet set. The stream socket handler will already
			 * have updated it if there has been a completed I/O.
			 */
			si->flags &= ~SI_FL_WAIT_DATA;
			if (!tick_isset(oc->wex)) {
				oc->wex = tick_add_ifset(now_ms, oc->wto);
				if (tick_isset(ic->rex) && !(si->flags & SI_FL_INDEP_STR)) {
					/* Note: depending on the protocol, we don't know if we're waiting
					 * for incoming data or not. So in order to prevent the socket from
					 * expiring read timeouts during writes, we refresh the read timeout,
					 * except if it was already infinite or if we have explicitly setup
					 * independent streams.
					 */
					ic->rex = tick_add_ifset(now_ms, ic->rto);
				}
			}
		}
	}
}
/* chk_rcv function for applets */
static void stream_int_chk_rcv_applet(struct stream_interface *si)
{
	struct channel *ic = si_ic(si);

	DPRINTF(stderr, "%s: si=%p, si->state=%d ic->flags=%08x oc->flags=%08x\n",
		__FUNCTION__,
		si, si->state, ic->flags, si_oc(si)->flags);

	if (unlikely(si->state != SI_ST_EST || (ic->flags & (CF_SHUTR|CF_DONT_READ))))
		return;
	/* here we only wake the applet up if it was waiting for some room */
	if (!(si->flags & SI_FL_WAIT_ROOM))
		return;

	if (channel_may_recv(ic) && !ic->pipe) {
		/* (re)start reading */
		appctx_wakeup(si_appctx(si));
	}
}
示例#3
0
/* Gets one text line out of a channel's buffer from a stream interface.
 * Return values :
 *   >0 : number of bytes read. Includes the \n if present before len or end.
 *   =0 : no '\n' before end found. <str> is left undefined.
 *   <0 : no more bytes readable because output is shut.
 * The channel status is not changed. The caller must call co_skip() to
 * update it. The '\n' is waited for as long as neither the buffer nor the
 * output are full. If either of them is full, the string may be returned
 * as is, without the '\n'.
 */
int co_getline(const struct channel *chn, char *str, int len)
{
	int ret, max;
	char *p;

	ret = 0;
	max = len;

	/* closed or empty + imminent close = -1; empty = 0 */
	if (unlikely((chn->flags & CF_SHUTW) || channel_is_empty(chn))) {
		if (chn->flags & (CF_SHUTW|CF_SHUTW_NOW))
			ret = -1;
		goto out;
	}

	p = co_head(chn);

	if (max > co_data(chn)) {
		max = co_data(chn);
		str[max-1] = 0;
	}
	while (max) {
		*str++ = *p;
		ret++;
		max--;

		if (*p == '\n')
			break;
		p = b_next(&chn->buf, p);
	}
	if (ret > 0 && ret < len &&
	    (ret < co_data(chn) || channel_may_recv(chn)) &&
	    *(str-1) != '\n' &&
	    !(chn->flags & (CF_SHUTW|CF_SHUTW_NOW)))
		ret = 0;
 out:
	if (max)
		*str = 0;
	return ret;
}
示例#4
0
/* Tries to copy character <c> into the channel's buffer after some length
 * controls. The chn->o and to_forward pointers are updated. If the channel
 * input is closed, -2 is returned. If there is not enough room left in the
 * buffer, -1 is returned. Otherwise the number of bytes copied is returned
 * (1). Channel flag READ_PARTIAL is updated if some data can be transferred.
 */
int ci_putchr(struct channel *chn, char c)
{
	if (unlikely(channel_input_closed(chn)))
		return -2;

	if (!channel_may_recv(chn))
		return -1;

	*ci_tail(chn) = c;

	b_add(&chn->buf, 1);
	chn->flags |= CF_READ_PARTIAL;

	if (chn->to_forward >= 1) {
		if (chn->to_forward != CHN_INFINITE_FORWARD)
			chn->to_forward--;
		c_adv(chn, 1);
	}

	chn->total++;
	return 1;
}
/* Callback to be used by connection I/O handlers upon completion. It propagates
 * connection flags to the stream interface, updates the stream (which may or
 * may not take this opportunity to try to forward data), then update the
 * connection's polling based on the channels and stream interface's final
 * states. The function always returns 0.
 */
static int si_conn_wake_cb(struct connection *conn)
{
	struct stream_interface *si = conn->owner;
	struct channel *ic = si_ic(si);
	struct channel *oc = si_oc(si);

	/* First step, report to the stream-int what was detected at the
	 * connection layer : errors and connection establishment.
	 */
	if (conn->flags & CO_FL_ERROR)
		si->flags |= SI_FL_ERR;

	if (unlikely(!(conn->flags & (CO_FL_WAIT_L4_CONN | CO_FL_WAIT_L6_CONN | CO_FL_CONNECTED)))) {
		si->exp = TICK_ETERNITY;
		oc->flags |= CF_WRITE_NULL;
	}

	/* Second step : update the stream-int and channels, try to forward any
	 * pending data, then possibly wake the stream up based on the new
	 * stream-int status.
	 */
	stream_int_notify(si);

	/* Third step : update the connection's polling status based on what
	 * was done above (eg: maybe some buffers got emptied).
	 */
	if (channel_is_empty(oc))
		__conn_data_stop_send(conn);


	if (si->flags & SI_FL_WAIT_ROOM) {
		__conn_data_stop_recv(conn);
	}
	else if ((ic->flags & (CF_SHUTR|CF_READ_PARTIAL|CF_DONT_READ)) == CF_READ_PARTIAL &&
		 channel_may_recv(ic)) {
		__conn_data_want_recv(conn);
	}
	return 0;
}
/* default chk_rcv function for scheduled tasks */
static void stream_int_chk_rcv(struct stream_interface *si)
{
	struct channel *ic = si_ic(si);

	DPRINTF(stderr, "%s: si=%p, si->state=%d ic->flags=%08x oc->flags=%08x\n",
		__FUNCTION__,
		si, si->state, ic->flags, si_oc(si)->flags);

	if (unlikely(si->state != SI_ST_EST || (ic->flags & (CF_SHUTR|CF_DONT_READ))))
		return;

	if (!channel_may_recv(ic) || ic->pipe) {
		/* stop reading */
		si->flags |= SI_FL_WAIT_ROOM;
	}
	else {
		/* (re)start reading */
		si->flags &= ~SI_FL_WAIT_ROOM;
		if (!(si->flags & SI_FL_DONT_WAKE))
			task_wakeup(si_task(si), TASK_WOKEN_IO);
	}
}
/* This function is used for inter-stream-interface calls. It is called by the
 * consumer to inform the producer side that it may be interested in checking
 * for free space in the buffer. Note that it intentionally does not update
 * timeouts, so that we can still check them later at wake-up. This function is
 * dedicated to connection-based stream interfaces.
 */
static void stream_int_chk_rcv_conn(struct stream_interface *si)
{
	struct channel *ic = si_ic(si);
	struct connection *conn = __objt_conn(si->end);

	if (unlikely(si->state > SI_ST_EST || (ic->flags & CF_SHUTR)))
		return;

	conn_refresh_polling_flags(conn);

	if ((ic->flags & CF_DONT_READ) || !channel_may_recv(ic)) {
		/* stop reading */
		if (!(ic->flags & CF_DONT_READ)) /* full */
			si->flags |= SI_FL_WAIT_ROOM;
		__conn_data_stop_recv(conn);
	}
	else {
		/* (re)start reading */
		si->flags &= ~SI_FL_WAIT_ROOM;
		__conn_data_want_recv(conn);
	}
	conn_cond_update_data_polling(conn);
}
/* Updates the polling status of a connection outside of the connection handler
 * based on the channel's flags and the stream interface's flags. It needs to be
 * called once after the channels' flags have settled down and the stream has
 * been updated. It is not designed to be called from within the connection
 * handler itself.
 */
void stream_int_update_conn(struct stream_interface *si)
{
	struct channel *ic = si_ic(si);
	struct channel *oc = si_oc(si);
	struct connection *conn = __objt_conn(si->end);

	if (!(ic->flags & CF_SHUTR)) {
		/* Read not closed */
		if ((ic->flags & CF_DONT_READ) || !channel_may_recv(ic))
			__conn_data_stop_recv(conn);
		else
			__conn_data_want_recv(conn);
	}

	if (!(oc->flags & CF_SHUTW)) {
		/* Write not closed */
		if (channel_is_empty(oc))
			__conn_data_stop_send(conn);
		else
			__conn_data_want_send(conn);
	}

	conn_cond_update_data_polling(conn);
}
/* This function is the equivalent to stream_int_update() except that it's
 * designed to be called from outside the stream handlers, typically the lower
 * layers (applets, connections) after I/O completion. After updating the stream
 * interface and timeouts, it will try to forward what can be forwarded, then to
 * wake the associated task up if an important event requires special handling.
 * It should not be called from within the stream itself, stream_int_update()
 * is designed for this.
 */
void stream_int_notify(struct stream_interface *si)
{
	struct channel *ic = si_ic(si);
	struct channel *oc = si_oc(si);

	/* process consumer side */
	if (channel_is_empty(oc)) {
		if (((oc->flags & (CF_SHUTW|CF_SHUTW_NOW)) == CF_SHUTW_NOW) &&
		    (si->state == SI_ST_EST))
			si_shutw(si);
		oc->wex = TICK_ETERNITY;
	}

	/* indicate that we may be waiting for data from the output channel */
	if ((oc->flags & (CF_SHUTW|CF_SHUTW_NOW)) == 0 && channel_may_recv(oc))
		si->flags |= SI_FL_WAIT_DATA;

	/* update OC timeouts and wake the other side up if it's waiting for room */
	if (oc->flags & CF_WRITE_ACTIVITY) {
		if ((oc->flags & (CF_SHUTW|CF_WRITE_PARTIAL)) == CF_WRITE_PARTIAL &&
		    !channel_is_empty(oc))
			if (tick_isset(oc->wex))
				oc->wex = tick_add_ifset(now_ms, oc->wto);

		if (!(si->flags & SI_FL_INDEP_STR))
			if (tick_isset(ic->rex))
				ic->rex = tick_add_ifset(now_ms, ic->rto);

		if (likely((oc->flags & (CF_SHUTW|CF_WRITE_PARTIAL|CF_DONT_READ)) == CF_WRITE_PARTIAL &&
			   channel_may_recv(oc) &&
			   (si_opposite(si)->flags & SI_FL_WAIT_ROOM)))
			si_chk_rcv(si_opposite(si));
	}

	/* Notify the other side when we've injected data into the IC that
	 * needs to be forwarded. We can do fast-forwarding as soon as there
	 * are output data, but we avoid doing this if some of the data are
	 * not yet scheduled for being forwarded, because it is very likely
	 * that it will be done again immediately afterwards once the following
	 * data are parsed (eg: HTTP chunking). We only SI_FL_WAIT_ROOM once
	 * we've emptied *some* of the output buffer, and not just when there
	 * is available room, because applets are often forced to stop before
	 * the buffer is full. We must not stop based on input data alone because
	 * an HTTP parser might need more data to complete the parsing.
	 */
	if (!channel_is_empty(ic) &&
	    (si_opposite(si)->flags & SI_FL_WAIT_DATA) &&
	    (ic->buf->i == 0 || ic->pipe)) {
		int new_len, last_len;

		last_len = ic->buf->o;
		if (ic->pipe)
			last_len += ic->pipe->data;

		si_chk_snd(si_opposite(si));

		new_len = ic->buf->o;
		if (ic->pipe)
			new_len += ic->pipe->data;

		/* check if the consumer has freed some space either in the
		 * buffer or in the pipe.
		 */
		if (channel_may_recv(ic) && new_len < last_len)
			si->flags &= ~SI_FL_WAIT_ROOM;
	}

	if (si->flags & SI_FL_WAIT_ROOM) {
		ic->rex = TICK_ETERNITY;
	}
	else if ((ic->flags & (CF_SHUTR|CF_READ_PARTIAL|CF_DONT_READ)) == CF_READ_PARTIAL &&
		 channel_may_recv(ic)) {
		/* we must re-enable reading if si_chk_snd() has freed some space */
		if (!(ic->flags & CF_READ_NOEXP) && tick_isset(ic->rex))
			ic->rex = tick_add_ifset(now_ms, ic->rto);
	}

	/* wake the task up only when needed */
	if (/* changes on the production side */
	    (ic->flags & (CF_READ_NULL|CF_READ_ERROR)) ||
	    si->state != SI_ST_EST ||
	    (si->flags & SI_FL_ERR) ||
	    ((ic->flags & CF_READ_PARTIAL) &&
	     (!ic->to_forward || si_opposite(si)->state != SI_ST_EST)) ||

	    /* changes on the consumption side */
	    (oc->flags & (CF_WRITE_NULL|CF_WRITE_ERROR)) ||
	    ((oc->flags & CF_WRITE_ACTIVITY) &&
	     ((oc->flags & CF_SHUTW) ||
	      ((oc->flags & CF_WAKE_WRITE) &&
	       (si_opposite(si)->state != SI_ST_EST ||
	        (channel_is_empty(oc) && !oc->to_forward)))))) {
		task_wakeup(si_task(si), TASK_WOKEN_IO);
	}
	if (ic->flags & CF_READ_ACTIVITY)
		ic->flags &= ~CF_READ_DONTWAIT;

	stream_release_buffers(si_strm(si));
}
/*
 * This is the callback which is called by the connection layer to receive data
 * into the buffer from the connection. It iterates over the transport layer's
 * rcv_buf function.
 */
static void si_conn_recv_cb(struct connection *conn)
{
	struct stream_interface *si = conn->owner;
	struct channel *ic = si_ic(si);
	int ret, max, cur_read;
	int read_poll = MAX_READ_POLL_LOOPS;

	/* stop immediately on errors. Note that we DON'T want to stop on
	 * POLL_ERR, as the poller might report a write error while there
	 * are still data available in the recv buffer. This typically
	 * happens when we send too large a request to a backend server
	 * which rejects it before reading it all.
	 */
	if (conn->flags & CO_FL_ERROR)
		return;

	/* stop here if we reached the end of data */
	if (conn_data_read0_pending(conn))
		goto out_shutdown_r;

	/* maybe we were called immediately after an asynchronous shutr */
	if (ic->flags & CF_SHUTR)
		return;

	cur_read = 0;

	if ((ic->flags & (CF_STREAMER | CF_STREAMER_FAST)) && !ic->buf->o &&
	    global.tune.idle_timer &&
	    (unsigned short)(now_ms - ic->last_read) >= global.tune.idle_timer) {
		/* The buffer was empty and nothing was transferred for more
		 * than one second. This was caused by a pause and not by
		 * congestion. Reset any streaming mode to reduce latency.
		 */
		ic->xfer_small = 0;
		ic->xfer_large = 0;
		ic->flags &= ~(CF_STREAMER | CF_STREAMER_FAST);
	}

	/* First, let's see if we may splice data across the channel without
	 * using a buffer.
	 */
	if (conn->xprt->rcv_pipe &&
	    (ic->pipe || ic->to_forward >= MIN_SPLICE_FORWARD) &&
	    ic->flags & CF_KERN_SPLICING) {
		if (buffer_not_empty(ic->buf)) {
			/* We're embarrassed, there are already data pending in
			 * the buffer and we don't want to have them at two
			 * locations at a time. Let's indicate we need some
			 * place and ask the consumer to hurry.
			 */
			goto abort_splice;
		}

		if (unlikely(ic->pipe == NULL)) {
			if (pipes_used >= global.maxpipes || !(ic->pipe = get_pipe())) {
				ic->flags &= ~CF_KERN_SPLICING;
				goto abort_splice;
			}
		}

		ret = conn->xprt->rcv_pipe(conn, ic->pipe, ic->to_forward);
		if (ret < 0) {
			/* splice not supported on this end, let's disable it */
			ic->flags &= ~CF_KERN_SPLICING;
			goto abort_splice;
		}

		if (ret > 0) {
			if (ic->to_forward != CHN_INFINITE_FORWARD)
				ic->to_forward -= ret;
			ic->total += ret;
			cur_read += ret;
			ic->flags |= CF_READ_PARTIAL;
		}

		if (conn_data_read0_pending(conn))
			goto out_shutdown_r;

		if (conn->flags & CO_FL_ERROR)
			return;

		if (conn->flags & CO_FL_WAIT_ROOM) {
			/* the pipe is full or we have read enough data that it
			 * could soon be full. Let's stop before needing to poll.
			 */
			si->flags |= SI_FL_WAIT_ROOM;
			__conn_data_stop_recv(conn);
		}

		/* splice not possible (anymore), let's go on on standard copy */
	}

 abort_splice:
	if (ic->pipe && unlikely(!ic->pipe->data)) {
		put_pipe(ic->pipe);
		ic->pipe = NULL;
	}

	/* now we'll need a buffer */
	if (!stream_alloc_recv_buffer(ic)) {
		si->flags |= SI_FL_WAIT_ROOM;
		goto end_recv;
	}

	/* Important note : if we're called with POLL_IN|POLL_HUP, it means the read polling
	 * was enabled, which implies that the recv buffer was not full. So we have a guarantee
	 * that if such an event is not handled above in splice, it will be handled here by
	 * recv().
	 */
	while (!(conn->flags & (CO_FL_ERROR | CO_FL_SOCK_RD_SH | CO_FL_DATA_RD_SH | CO_FL_WAIT_ROOM | CO_FL_HANDSHAKE))) {
		max = channel_recv_max(ic);

		if (!max) {
			si->flags |= SI_FL_WAIT_ROOM;
			break;
		}

		ret = conn->xprt->rcv_buf(conn, ic->buf, max);
		if (ret <= 0)
			break;

		cur_read += ret;

		/* if we're allowed to directly forward data, we must update ->o */
		if (ic->to_forward && !(ic->flags & (CF_SHUTW|CF_SHUTW_NOW))) {
			unsigned long fwd = ret;
			if (ic->to_forward != CHN_INFINITE_FORWARD) {
				if (fwd > ic->to_forward)
					fwd = ic->to_forward;
				ic->to_forward -= fwd;
			}
			b_adv(ic->buf, fwd);
		}

		ic->flags |= CF_READ_PARTIAL;
		ic->total += ret;

		if (!channel_may_recv(ic)) {
			si->flags |= SI_FL_WAIT_ROOM;
			break;
		}

		if ((ic->flags & CF_READ_DONTWAIT) || --read_poll <= 0) {
			si->flags |= SI_FL_WAIT_ROOM;
			__conn_data_stop_recv(conn);
			break;
		}

		/* if too many bytes were missing from last read, it means that
		 * it's pointless trying to read again because the system does
		 * not have them in buffers.
		 */
		if (ret < max) {
			/* if a streamer has read few data, it may be because we
			 * have exhausted system buffers. It's not worth trying
			 * again.
			 */
			if (ic->flags & CF_STREAMER)
				break;

			/* if we read a large block smaller than what we requested,
			 * it's almost certain we'll never get anything more.
			 */
			if (ret >= global.tune.recv_enough)
				break;
		}
	} /* while !flags */

	if (cur_read) {
		if ((ic->flags & (CF_STREAMER | CF_STREAMER_FAST)) &&
		    (cur_read <= ic->buf->size / 2)) {
			ic->xfer_large = 0;
			ic->xfer_small++;
			if (ic->xfer_small >= 3) {
				/* we have read less than half of the buffer in
				 * one pass, and this happened at least 3 times.
				 * This is definitely not a streamer.
				 */
				ic->flags &= ~(CF_STREAMER | CF_STREAMER_FAST);
			}
			else if (ic->xfer_small >= 2) {
				/* if the buffer has been at least half full twice,
				 * we receive faster than we send, so at least it
				 * is not a "fast streamer".
				 */
				ic->flags &= ~CF_STREAMER_FAST;
			}
		}
		else if (!(ic->flags & CF_STREAMER_FAST) &&
			 (cur_read >= ic->buf->size - global.tune.maxrewrite)) {
			/* we read a full buffer at once */
			ic->xfer_small = 0;
			ic->xfer_large++;
			if (ic->xfer_large >= 3) {
				/* we call this buffer a fast streamer if it manages
				 * to be filled in one call 3 consecutive times.
				 */
				ic->flags |= (CF_STREAMER | CF_STREAMER_FAST);
			}
		}
		else {
			ic->xfer_small = 0;
			ic->xfer_large = 0;
		}
		ic->last_read = now_ms;
	}

 end_recv:
	if (conn->flags & CO_FL_ERROR)
		return;

	if (conn_data_read0_pending(conn))
		/* connection closed */
		goto out_shutdown_r;

	return;

 out_shutdown_r:
	/* we received a shutdown */
	ic->flags |= CF_READ_NULL;
	if (ic->flags & CF_AUTO_CLOSE)
		channel_shutw_now(ic);
	stream_sock_read0(si);
	conn_data_read0(conn);
	return;
}
示例#11
0
/* Callback to be used by connection I/O handlers upon completion. It differs from
 * the update function in that it is designed to be called by lower layers after I/O
 * events have been completed. It will also try to wake the associated task up if
 * an important event requires special handling. It relies on the connection handler
 * to commit any polling updates. The function always returns 0.
 */
static int si_conn_wake_cb(struct connection *conn)
{
	struct stream_interface *si = conn->owner;
	struct channel *ic = si_ic(si);
	struct channel *oc = si_oc(si);

	DPRINTF(stderr, "%s: si=%p, si->state=%d ic->flags=%08x oc->flags=%08x\n",
		__FUNCTION__,
		si, si->state, ic->flags, oc->flags);

	if (conn->flags & CO_FL_ERROR)
		si->flags |= SI_FL_ERR;

	/* check for recent connection establishment */
	if (unlikely(!(conn->flags & (CO_FL_WAIT_L4_CONN | CO_FL_WAIT_L6_CONN | CO_FL_CONNECTED)))) {
		si->exp = TICK_ETERNITY;
		oc->flags |= CF_WRITE_NULL;
	}

	/* process consumer side */
	if (channel_is_empty(oc)) {
		if (((oc->flags & (CF_SHUTW|CF_SHUTW_NOW)) == CF_SHUTW_NOW) &&
		    (si->state == SI_ST_EST))
			stream_int_shutw_conn(si);
		__conn_data_stop_send(conn);
		oc->wex = TICK_ETERNITY;
	}

	if ((oc->flags & (CF_SHUTW|CF_SHUTW_NOW)) == 0 && channel_may_recv(oc))
		si->flags |= SI_FL_WAIT_DATA;

	if (oc->flags & CF_WRITE_ACTIVITY) {
		/* update timeouts if we have written something */
		if ((oc->flags & (CF_SHUTW|CF_WRITE_PARTIAL)) == CF_WRITE_PARTIAL &&
		    !channel_is_empty(oc))
			if (tick_isset(oc->wex))
				oc->wex = tick_add_ifset(now_ms, oc->wto);

		if (!(si->flags & SI_FL_INDEP_STR))
			if (tick_isset(ic->rex))
				ic->rex = tick_add_ifset(now_ms, ic->rto);

		if (likely((oc->flags & (CF_SHUTW|CF_WRITE_PARTIAL|CF_DONT_READ)) == CF_WRITE_PARTIAL &&
			   channel_may_recv(oc) &&
			   (si_opposite(si)->flags & SI_FL_WAIT_ROOM)))
			si_chk_rcv(si_opposite(si));
	}

	/* process producer side.
	 * We might have some data the consumer is waiting for.
	 * We can do fast-forwarding, but we avoid doing this for partial
	 * buffers, because it is very likely that it will be done again
	 * immediately afterwards once the following data is parsed (eg:
	 * HTTP chunking).
	 */
	if (((ic->flags & CF_READ_PARTIAL) && !channel_is_empty(ic)) &&
	    (ic->pipe /* always try to send spliced data */ ||
	     (si_ib(si)->i == 0 && (si_opposite(si)->flags & SI_FL_WAIT_DATA)))) {
		int last_len = ic->pipe ? ic->pipe->data : 0;

		si_chk_snd(si_opposite(si));

		/* check if the consumer has freed some space either in the
		 * buffer or in the pipe.
		 */
		if (channel_may_recv(ic) &&
		    (!last_len || !ic->pipe || ic->pipe->data < last_len))
			si->flags &= ~SI_FL_WAIT_ROOM;
	}

	if (si->flags & SI_FL_WAIT_ROOM) {
		__conn_data_stop_recv(conn);
		ic->rex = TICK_ETERNITY;
	}
	else if ((ic->flags & (CF_SHUTR|CF_READ_PARTIAL|CF_DONT_READ)) == CF_READ_PARTIAL &&
		 channel_may_recv(ic)) {
		/* we must re-enable reading if si_chk_snd() has freed some space */
		__conn_data_want_recv(conn);
		if (!(ic->flags & CF_READ_NOEXP) && tick_isset(ic->rex))
			ic->rex = tick_add_ifset(now_ms, ic->rto);
	}

	/* wake the task up only when needed */
	if (/* changes on the production side */
	    (ic->flags & (CF_READ_NULL|CF_READ_ERROR)) ||
	    si->state != SI_ST_EST ||
	    (si->flags & SI_FL_ERR) ||
	    ((ic->flags & CF_READ_PARTIAL) &&
	     (!ic->to_forward || si_opposite(si)->state != SI_ST_EST)) ||

	    /* changes on the consumption side */
	    (oc->flags & (CF_WRITE_NULL|CF_WRITE_ERROR)) ||
	    ((oc->flags & CF_WRITE_ACTIVITY) &&
	     ((oc->flags & CF_SHUTW) ||
	      ((oc->flags & CF_WAKE_WRITE) &&
	       (si_opposite(si)->state != SI_ST_EST ||
	        (channel_is_empty(oc) && !oc->to_forward)))))) {
		task_wakeup(si_task(si), TASK_WOKEN_IO);
	}
	if (ic->flags & CF_READ_ACTIVITY)
		ic->flags &= ~CF_READ_DONTWAIT;

	session_release_buffers(si_sess(si));
	return 0;
}
示例#12
0
/* default update function for embedded tasks, to be used at the end of the i/o handler */
static void stream_int_update_embedded(struct stream_interface *si)
{
	int old_flags = si->flags;
	struct channel *ic = si_ic(si);
	struct channel *oc = si_oc(si);

	DPRINTF(stderr, "%s: si=%p, si->state=%d ic->flags=%08x oc->flags=%08x\n",
		__FUNCTION__,
		si, si->state, ic->flags, oc->flags);

	if (si->state != SI_ST_EST)
		return;

	if ((oc->flags & (CF_SHUTW|CF_SHUTW_NOW)) == CF_SHUTW_NOW &&
	    channel_is_empty(oc))
		si_shutw(si);

	if ((oc->flags & (CF_SHUTW|CF_SHUTW_NOW)) == 0 && channel_may_recv(oc))
		si->flags |= SI_FL_WAIT_DATA;

	/* we're almost sure that we need some space if the buffer is not
	 * empty, even if it's not full, because the applets can't fill it.
	 */
	if ((ic->flags & (CF_SHUTR|CF_DONT_READ)) == 0 && !channel_is_empty(ic))
		si->flags |= SI_FL_WAIT_ROOM;

	if (oc->flags & CF_WRITE_ACTIVITY) {
		if (tick_isset(oc->wex))
			oc->wex = tick_add_ifset(now_ms, oc->wto);
	}

	if (ic->flags & CF_READ_ACTIVITY ||
	    (oc->flags & CF_WRITE_ACTIVITY && !(si->flags & SI_FL_INDEP_STR))) {
		if (tick_isset(ic->rex))
			ic->rex = tick_add_ifset(now_ms, ic->rto);
	}

	/* save flags to detect changes */
	old_flags = si->flags;
	if (likely((oc->flags & (CF_SHUTW|CF_WRITE_PARTIAL|CF_DONT_READ)) == CF_WRITE_PARTIAL &&
		   channel_may_recv(oc) &&
		   (si_opposite(si)->flags & SI_FL_WAIT_ROOM)))
		si_chk_rcv(si_opposite(si));

	if (((ic->flags & CF_READ_PARTIAL) && !channel_is_empty(ic)) &&
	    (ic->pipe /* always try to send spliced data */ ||
	     (ic->buf->i == 0 && (si_opposite(si)->flags & SI_FL_WAIT_DATA)))) {
		si_chk_snd(si_opposite(si));
		/* check if the consumer has freed some space */
		if (channel_may_recv(ic) && !ic->pipe)
			si->flags &= ~SI_FL_WAIT_ROOM;
	}

	/* Note that we're trying to wake up in two conditions here :
	 *  - special event, which needs the holder task attention
	 *  - status indicating that the applet can go on working. This
	 *    is rather hard because we might be blocking on output and
	 *    don't want to wake up on input and vice-versa. The idea is
	 *    to only rely on the changes the chk_* might have performed.
	 */
	if (/* check stream interface changes */
	    ((old_flags & ~si->flags) & (SI_FL_WAIT_ROOM|SI_FL_WAIT_DATA)) ||

	    /* changes on the production side */
	    (ic->flags & (CF_READ_NULL|CF_READ_ERROR)) ||
	    si->state != SI_ST_EST ||
	    (si->flags & SI_FL_ERR) ||
	    ((ic->flags & CF_READ_PARTIAL) &&
	     (!ic->to_forward || si_opposite(si)->state != SI_ST_EST)) ||

	    /* changes on the consumption side */
	    (oc->flags & (CF_WRITE_NULL|CF_WRITE_ERROR)) ||
	    ((oc->flags & CF_WRITE_ACTIVITY) &&
	     ((oc->flags & CF_SHUTW) ||
	      ((oc->flags & CF_WAKE_WRITE) &&
	       (si_opposite(si)->state != SI_ST_EST ||
	        (channel_is_empty(oc) && !oc->to_forward)))))) {
		if (!(si->flags & SI_FL_DONT_WAKE))
			task_wakeup(si_task(si), TASK_WOKEN_IO);
	}
	if (ic->flags & CF_READ_ACTIVITY)
		ic->flags &= ~CF_READ_DONTWAIT;
}