/* default chk_snd function for scheduled tasks */
static void stream_int_chk_snd(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;
if (!(si->flags & SI_FL_WAIT_DATA) || /* not waiting for data */
channel_is_empty(oc)) /* 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(oc->wex))
oc->wex = tick_add_ifset(now_ms, oc->wto);
if (!(si->flags & SI_FL_DONT_WAKE))
task_wakeup(si_task(si), TASK_WOKEN_IO);
}
/*
* This function performs a shutdown-read on a detached stream interface in a
* connected or init state (it does nothing for other states). It either shuts
* the read side or marks itself as closed. The buffer flags are updated to
* reflect the new state. If the stream interface has SI_FL_NOHALF, we also
* forward the close to the write side. The owner task is woken up if it exists.
*/
static void stream_int_shutr(struct stream_interface *si)
{
struct channel *ic = si_ic(si);
ic->flags &= ~CF_SHUTR_NOW;
if (ic->flags & CF_SHUTR)
return;
ic->flags |= CF_SHUTR;
ic->rex = TICK_ETERNITY;
si->flags &= ~SI_FL_WAIT_ROOM;
if (si->state != SI_ST_EST && si->state != SI_ST_CON)
return;
if (si_oc(si)->flags & CF_SHUTW) {
si->state = SI_ST_DIS;
si->exp = TICK_ETERNITY;
}
else if (si->flags & SI_FL_NOHALF) {
/* we want to immediately forward this close to the write side */
return stream_int_shutw(si);
}
/* note that if the task exists, it must unregister itself once it runs */
if (!(si->flags & SI_FL_DONT_WAKE))
task_wakeup(si_task(si), TASK_WOKEN_IO);
}
/* Register an applet to handle a stream_interface as a new appctx. The SI will
* wake it up everytime it is solicited. The appctx must be deleted by the task
* handler using si_release_endpoint(), possibly from within the function itself.
* It also pre-initializes the applet's context and returns it (or NULL in case
* it could not be allocated).
*/
struct appctx *stream_int_register_handler(struct stream_interface *si, struct applet *app)
{
struct appctx *appctx;
DPRINTF(stderr, "registering handler %p for si %p (was %p)\n", app, si, si_task(si));
appctx = si_alloc_appctx(si, app);
if (!appctx)
return NULL;
si_applet_cant_get(si);
appctx_wakeup(appctx);
return si_appctx(si);
}
/* Register an applet to handle a stream_interface as part of the
* stream interface's owner task. The SI will wake it up everytime it
* is solicited. The task's processing function must call the applet's
* function before returning. It must be deleted by the task handler
* using stream_int_unregister_handler(), possibly from within the
* function itself. It also pre-initializes the applet's context and
* returns it (or NULL in case it could not be allocated).
*/
struct appctx *stream_int_register_handler(struct stream_interface *si, struct si_applet *app)
{
struct appctx *appctx;
DPRINTF(stderr, "registering handler %p for si %p (was %p)\n", app, si, si_task(si));
appctx = si_alloc_appctx(si);
if (!appctx)
return NULL;
appctx_set_applet(appctx, app);
si->flags |= SI_FL_WAIT_DATA;
return si_appctx(si);
}
/*
* This function performs a shutdown-write on a stream interface attached to an
* applet in a connected or init state (it does nothing for other states). It
* either shuts the write side or marks itself as closed. The buffer flags are
* updated to reflect the new state. It does also close everything if the SI
* was marked as being in error state. The owner task is woken up if it exists.
*/
static void stream_int_shutw(struct stream_interface *si)
{
struct channel *ic = si_ic(si);
struct channel *oc = si_oc(si);
oc->flags &= ~CF_SHUTW_NOW;
if (oc->flags & CF_SHUTW)
return;
oc->flags |= CF_SHUTW;
oc->wex = TICK_ETERNITY;
si->flags &= ~SI_FL_WAIT_DATA;
switch (si->state) {
case SI_ST_EST:
/* we have to shut before closing, otherwise some short messages
* may never leave the system, especially when there are remaining
* unread data in the socket input buffer, or when nolinger is set.
* However, if SI_FL_NOLINGER is explicitly set, we know there is
* no risk so we close both sides immediately.
*/
if (!(si->flags & (SI_FL_ERR | SI_FL_NOLINGER)) &&
!(ic->flags & (CF_SHUTR|CF_DONT_READ)))
return;
/* fall through */
case SI_ST_CON:
case SI_ST_CER:
case SI_ST_QUE:
case SI_ST_TAR:
/* Note that none of these states may happen with applets */
si->state = SI_ST_DIS;
si_applet_release(si);
default:
si->flags &= ~(SI_FL_WAIT_ROOM | SI_FL_NOLINGER);
ic->flags &= ~CF_SHUTR_NOW;
ic->flags |= CF_SHUTR;
ic->rex = TICK_ETERNITY;
si->exp = TICK_ETERNITY;
}
/* note that if the task exists, it must unregister itself once it runs */
if (!(si->flags & SI_FL_DONT_WAKE))
task_wakeup(si_task(si), TASK_WOKEN_IO);
}
/* 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);
}
}
/* Callback to be used by applet handlers upon completion. It updates the stream
* (which may or may not take this opportunity to try to forward data), then
* may disable the applet's based on the channels and stream interface's final
* states.
*/
void si_applet_wake_cb(struct stream_interface *si)
{
struct channel *ic = si_ic(si);
/* If the applet wants to write and the channel is closed, it's a
* broken pipe and it must be reported.
*/
if ((si->flags & SI_FL_WANT_PUT) && (ic->flags & CF_SHUTR))
si->flags |= SI_FL_ERR;
/* update the stream-int, channels, and possibly wake the stream up */
stream_int_notify(si);
/* Get away from the active list if we can't work anymore.
* We also do that if the main task has already scheduled, because it
* saves a useless wakeup/pause/wakeup cycle causing one useless call
* per session on average.
*/
if (task_in_rq(si_task(si)) ||
(((si->flags & (SI_FL_WANT_PUT|SI_FL_WAIT_ROOM)) != SI_FL_WANT_PUT) &&
((si->flags & (SI_FL_WANT_GET|SI_FL_WAIT_DATA)) != SI_FL_WANT_GET)))
appctx_pause(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 *oc = si_oc(si);
struct connection *conn = __objt_conn(si->end);
if (unlikely(si->state > SI_ST_EST || (oc->flags & CF_SHUTW)))
return;
if (unlikely(channel_is_empty(oc))) /* called with nothing to send ! */
return;
if (!oc->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(oc)) {
/* 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 (((oc->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 ((oc->flags & (CF_SHUTW|CF_SHUTW_NOW)) == 0)
si->flags |= SI_FL_WAIT_DATA;
oc->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(oc->wex))
oc->wex = tick_add_ifset(now_ms, oc->wto);
}
if (likely(oc->flags & CF_WRITE_ACTIVITY)) {
struct channel *ic = si_ic(si);
/* update timeout if we have written something */
if ((oc->flags & (CF_SHUTW|CF_WRITE_PARTIAL)) == CF_WRITE_PARTIAL &&
!channel_is_empty(oc))
oc->wex = tick_add_ifset(now_ms, oc->wto);
if (tick_isset(ic->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.
*/
ic->rex = tick_add_ifset(now_ms, ic->rto);
}
}
/* in case of special condition (error, shutdown, end of write...), we
* have to notify the task.
*/
if (likely((oc->flags & (CF_WRITE_NULL|CF_WRITE_ERROR|CF_SHUTW)) ||
((oc->flags & CF_WAKE_WRITE) &&
((channel_is_empty(oc) && !oc->to_forward) ||
si->state != SI_ST_EST)))) {
out_wakeup:
if (!(si->flags & SI_FL_DONT_WAKE))
task_wakeup(si_task(si), TASK_WOKEN_IO);
}
/* commit possible polling changes */
conn_cond_update_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));
}
/* 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;
}
/* 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;
}
