/* 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)); } }
/* 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; }
/* 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; }
/* 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; }