/* default chk_snd function for scheduled tasks */
static void stream_int_chk_snd(struct stream_interface *si)
{
struct channel *ob = si->ob;
DPRINTF(stderr, "%s: si=%p, si->state=%d ib->flags=%08x ob->flags=%08x\n",
__FUNCTION__,
si, si->state, si->ib->flags, si->ob->flags);
if (unlikely(si->state != SI_ST_EST || (si->ob->flags & CF_SHUTW)))
return;
if (!(si->flags & SI_FL_WAIT_DATA) || /* not waiting for data */
channel_is_empty(ob)) /* called with nothing to send ! */
return;
/* Otherwise there are remaining data to be sent in the buffer,
* so we tell the handler.
*/
si->flags &= ~SI_FL_WAIT_DATA;
if (!tick_isset(ob->wex))
ob->wex = tick_add_ifset(now_ms, ob->wto);
if (!(si->flags & SI_FL_DONT_WAKE) && si->owner)
task_wakeup(si->owner, TASK_WOKEN_IO);
}
/* 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);
}
}
}
}
}
/* 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 bo_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 bo_getline(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 = bo_ptr(chn->buf);
if (max > chn->buf->o) {
max = chn->buf->o;
str[max-1] = 0;
}
while (max) {
*str++ = *p;
ret++;
max--;
if (*p == '\n')
break;
p = buffer_wrap_add(chn->buf, p + 1);
}
if (ret > 0 && ret < len &&
(ret < chn->buf->o || !channel_full(chn)) &&
*(str-1) != '\n' &&
!(chn->flags & (CF_SHUTW|CF_SHUTW_NOW)))
ret = 0;
out:
if (max)
*str = 0;
return ret;
}
/* 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;
}
/* 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;
}
/* 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);
}
/* chk_snd function for applets */
static void stream_int_chk_snd_applet(struct stream_interface *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, si_ic(si)->flags, oc->flags);
if (unlikely(si->state != SI_ST_EST || (oc->flags & CF_SHUTW)))
return;
/* we only wake the applet up if it was waiting for some data */
if (!(si->flags & SI_FL_WAIT_DATA))
return;
if (!tick_isset(oc->wex))
oc->wex = tick_add_ifset(now_ms, oc->wto);
if (!channel_is_empty(oc)) {
/* (re)start sending */
appctx_wakeup(si_appctx(si));
}
}
/* This function is used for inter-stream-interface calls. It is called by the
* producer to inform the consumer side that it may be interested in checking
* for data in the buffer. Note that it intentionally does not update timeouts,
* so that we can still check them later at wake-up.
*/
static void stream_int_chk_snd_conn(struct stream_interface *si)
{
struct channel *ob = si->ob;
struct connection *conn = __objt_conn(si->end);
if (unlikely(si->state > SI_ST_EST || (ob->flags & CF_SHUTW)))
return;
if (unlikely(channel_is_empty(ob))) /* called with nothing to send ! */
return;
if (!ob->pipe && /* spliced data wants to be forwarded ASAP */
!(si->flags & SI_FL_WAIT_DATA)) /* not waiting for data */
return;
if (conn->flags & (CO_FL_DATA_WR_ENA|CO_FL_CURR_WR_ENA)) {
/* already subscribed to write notifications, will be called
* anyway, so let's avoid calling it especially if the reader
* is not ready.
*/
return;
}
/* Before calling the data-level operations, we have to prepare
* the polling flags to ensure we properly detect changes.
*/
conn_refresh_polling_flags(conn);
__conn_data_want_send(conn);
if (!(conn->flags & (CO_FL_HANDSHAKE|CO_FL_WAIT_L4_CONN|CO_FL_WAIT_L6_CONN))) {
si_conn_send(conn);
if (conn->flags & CO_FL_ERROR) {
/* Write error on the file descriptor */
__conn_data_stop_both(conn);
si->flags |= SI_FL_ERR;
goto out_wakeup;
}
}
/* OK, so now we know that some data might have been sent, and that we may
* have to poll first. We have to do that too if the buffer is not empty.
*/
if (channel_is_empty(ob)) {
/* the connection is established but we can't write. Either the
* buffer is empty, or we just refrain from sending because the
* ->o limit was reached. Maybe we just wrote the last
* chunk and need to close.
*/
__conn_data_stop_send(conn);
if (((ob->flags & (CF_SHUTW|CF_AUTO_CLOSE|CF_SHUTW_NOW)) ==
(CF_AUTO_CLOSE|CF_SHUTW_NOW)) &&
(si->state == SI_ST_EST)) {
si_shutw(si);
goto out_wakeup;
}
if ((ob->flags & (CF_SHUTW|CF_SHUTW_NOW)) == 0)
si->flags |= SI_FL_WAIT_DATA;
ob->wex = TICK_ETERNITY;
}
else {
/* Otherwise there are remaining data to be sent in the buffer,
* which means we have to poll before doing so.
*/
__conn_data_want_send(conn);
si->flags &= ~SI_FL_WAIT_DATA;
if (!tick_isset(ob->wex))
ob->wex = tick_add_ifset(now_ms, ob->wto);
}
if (likely(ob->flags & CF_WRITE_ACTIVITY)) {
/* update timeout if we have written something */
if ((ob->flags & (CF_SHUTW|CF_WRITE_PARTIAL)) == CF_WRITE_PARTIAL &&
!channel_is_empty(ob))
ob->wex = tick_add_ifset(now_ms, ob->wto);
if (tick_isset(si->ib->rex) && !(si->flags & SI_FL_INDEP_STR)) {
/* Note: to prevent the client from expiring read timeouts
* during writes, we refresh it. We only do this if the
* interface is not configured for "independent streams",
* because for some applications it's better not to do this,
* for instance when continuously exchanging small amounts
* of data which can full the socket buffers long before a
* write timeout is detected.
*/
si->ib->rex = tick_add_ifset(now_ms, si->ib->rto);
}
}
/* in case of special condition (error, shutdown, end of write...), we
* have to notify the task.
*/
if (likely((ob->flags & (CF_WRITE_NULL|CF_WRITE_ERROR|CF_SHUTW)) ||
((ob->flags & CF_WAKE_WRITE) &&
((channel_is_empty(si->ob) && !ob->to_forward) ||
si->state != SI_ST_EST)))) {
out_wakeup:
if (!(si->flags & SI_FL_DONT_WAKE) && si->owner)
task_wakeup(si->owner, TASK_WOKEN_IO);
}
/* commit possible polling changes */
conn_cond_update_polling(conn);
}
/* 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;
DPRINTF(stderr, "%s: si=%p, si->state=%d ib->flags=%08x ob->flags=%08x\n",
__FUNCTION__,
si, si->state, si->ib->flags, si->ob->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;
si->ob->flags |= CF_WRITE_NULL;
}
/* process consumer side */
if (channel_is_empty(si->ob)) {
if (((si->ob->flags & (CF_SHUTW|CF_SHUTW_NOW)) == CF_SHUTW_NOW) &&
(si->state == SI_ST_EST))
stream_int_shutw_conn(si);
__conn_data_stop_send(conn);
si->ob->wex = TICK_ETERNITY;
}
if ((si->ob->flags & (CF_SHUTW|CF_SHUTW_NOW)) == 0 && !channel_full(si->ob))
si->flags |= SI_FL_WAIT_DATA;
if (si->ob->flags & CF_WRITE_ACTIVITY) {
/* update timeouts if we have written something */
if ((si->ob->flags & (CF_SHUTW|CF_WRITE_PARTIAL)) == CF_WRITE_PARTIAL &&
!channel_is_empty(si->ob))
if (tick_isset(si->ob->wex))
si->ob->wex = tick_add_ifset(now_ms, si->ob->wto);
if (!(si->flags & SI_FL_INDEP_STR))
if (tick_isset(si->ib->rex))
si->ib->rex = tick_add_ifset(now_ms, si->ib->rto);
if (likely((si->ob->flags & (CF_SHUTW|CF_WRITE_PARTIAL|CF_DONT_READ)) == CF_WRITE_PARTIAL &&
!channel_full(si->ob) &&
(si->ob->prod->flags & SI_FL_WAIT_ROOM)))
si_chk_rcv(si->ob->prod);
}
/* 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 (((si->ib->flags & CF_READ_PARTIAL) && !channel_is_empty(si->ib)) &&
(si->ib->pipe /* always try to send spliced data */ ||
(si->ib->buf->i == 0 && (si->ib->cons->flags & SI_FL_WAIT_DATA)))) {
int last_len = si->ib->pipe ? si->ib->pipe->data : 0;
si_chk_snd(si->ib->cons);
/* check if the consumer has freed some space either in the
* buffer or in the pipe.
*/
if (!channel_full(si->ib) &&
(!last_len || !si->ib->pipe || si->ib->pipe->data < last_len))
si->flags &= ~SI_FL_WAIT_ROOM;
}
if (si->flags & SI_FL_WAIT_ROOM) {
__conn_data_stop_recv(conn);
si->ib->rex = TICK_ETERNITY;
}
else if ((si->ib->flags & (CF_SHUTR|CF_READ_PARTIAL|CF_DONT_READ)) == CF_READ_PARTIAL &&
!channel_full(si->ib)) {
/* we must re-enable reading if si_chk_snd() has freed some space */
__conn_data_want_recv(conn);
if (!(si->ib->flags & CF_READ_NOEXP) && tick_isset(si->ib->rex))
si->ib->rex = tick_add_ifset(now_ms, si->ib->rto);
}
/* wake the task up only when needed */
if (/* changes on the production side */
(si->ib->flags & (CF_READ_NULL|CF_READ_ERROR)) ||
si->state != SI_ST_EST ||
(si->flags & SI_FL_ERR) ||
((si->ib->flags & CF_READ_PARTIAL) &&
(!si->ib->to_forward || si->ib->cons->state != SI_ST_EST)) ||
/* changes on the consumption side */
(si->ob->flags & (CF_WRITE_NULL|CF_WRITE_ERROR)) ||
((si->ob->flags & CF_WRITE_ACTIVITY) &&
((si->ob->flags & CF_SHUTW) ||
((si->ob->flags & CF_WAKE_WRITE) &&
(si->ob->prod->state != SI_ST_EST ||
(channel_is_empty(si->ob) && !si->ob->to_forward)))))) {
task_wakeup(si->owner, TASK_WOKEN_IO);
}
if (si->ib->flags & CF_READ_ACTIVITY)
si->ib->flags &= ~CF_READ_DONTWAIT;
return 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;
DPRINTF(stderr, "%s: si=%p, si->state=%d ib->flags=%08x ob->flags=%08x\n",
__FUNCTION__,
si, si->state, si->ib->flags, si->ob->flags);
if (si->state != SI_ST_EST)
return;
if ((si->ob->flags & (CF_SHUTW|CF_SHUTW_NOW)) == CF_SHUTW_NOW &&
channel_is_empty(si->ob))
si_shutw(si);
if ((si->ob->flags & (CF_SHUTW|CF_SHUTW_NOW)) == 0 && !channel_full(si->ob))
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 ((si->ib->flags & (CF_SHUTR|CF_DONT_READ)) == 0 && !channel_is_empty(si->ib))
si->flags |= SI_FL_WAIT_ROOM;
if (si->ob->flags & CF_WRITE_ACTIVITY) {
if (tick_isset(si->ob->wex))
si->ob->wex = tick_add_ifset(now_ms, si->ob->wto);
}
if (si->ib->flags & CF_READ_ACTIVITY ||
(si->ob->flags & CF_WRITE_ACTIVITY && !(si->flags & SI_FL_INDEP_STR))) {
if (tick_isset(si->ib->rex))
si->ib->rex = tick_add_ifset(now_ms, si->ib->rto);
}
/* save flags to detect changes */
old_flags = si->flags;
if (likely((si->ob->flags & (CF_SHUTW|CF_WRITE_PARTIAL|CF_DONT_READ)) == CF_WRITE_PARTIAL &&
!channel_full(si->ob) &&
(si->ob->prod->flags & SI_FL_WAIT_ROOM)))
si_chk_rcv(si->ob->prod);
if (((si->ib->flags & CF_READ_PARTIAL) && !channel_is_empty(si->ib)) &&
(si->ib->cons->flags & SI_FL_WAIT_DATA)) {
si_chk_snd(si->ib->cons);
/* check if the consumer has freed some space */
if (!channel_full(si->ib))
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 */
(si->ib->flags & (CF_READ_NULL|CF_READ_ERROR)) ||
si->state != SI_ST_EST ||
(si->flags & SI_FL_ERR) ||
((si->ib->flags & CF_READ_PARTIAL) &&
(!si->ib->to_forward || si->ib->cons->state != SI_ST_EST)) ||
/* changes on the consumption side */
(si->ob->flags & (CF_WRITE_NULL|CF_WRITE_ERROR)) ||
((si->ob->flags & CF_WRITE_ACTIVITY) &&
((si->ob->flags & CF_SHUTW) ||
((si->ob->flags & CF_WAKE_WRITE) &&
(si->ob->prod->state != SI_ST_EST ||
(channel_is_empty(si->ob) && !si->ob->to_forward)))))) {
if (!(si->flags & SI_FL_DONT_WAKE) && si->owner)
task_wakeup(si->owner, TASK_WOKEN_IO);
}
if (si->ib->flags & CF_READ_ACTIVITY)
si->ib->flags &= ~CF_READ_DONTWAIT;
}
/* 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));
}