461 lines
23 KiB
Diff
461 lines
23 KiB
Diff
diff --git a/modules/http2/h2_session.c b/modules/http2/h2_session.c
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index 814d2a96..a1b31d2b 100644
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--- a/modules/http2/h2_session.c
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+++ b/modules/http2/h2_session.c
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@@ -235,6 +235,7 @@ static int on_data_chunk_recv_cb(nghttp2_session *ngh2, uint8_t flags,
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stream = h2_session_stream_get(session, stream_id);
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if (stream) {
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status = h2_stream_recv_DATA(stream, flags, data, len);
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+ dispatch_event(session, H2_SESSION_EV_STREAM_CHANGE, 0, "stream data rcvd");
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}
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else {
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ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, session->c, APLOGNO(03064)
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@@ -317,9 +318,9 @@ static int on_header_cb(nghttp2_session *ngh2, const nghttp2_frame *frame,
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}
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/**
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- * nghttp2 session has received a complete frame. Most, it uses
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- * for processing of internal state. HEADER and DATA frames however
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- * we need to handle ourself.
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+ * nghttp2 session has received a complete frame. Most are used by nghttp2
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+ * for processing of internal state. Some, like HEADER and DATA frames,
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+ * we need to act on.
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*/
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static int on_frame_recv_cb(nghttp2_session *ng2s,
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const nghttp2_frame *frame,
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@@ -378,6 +379,9 @@ static int on_frame_recv_cb(nghttp2_session *ng2s,
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"h2_stream(%ld-%d): WINDOW_UPDATE incr=%d",
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session->id, (int)frame->hd.stream_id,
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frame->window_update.window_size_increment);
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+ if (nghttp2_session_want_write(session->ngh2)) {
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+ dispatch_event(session, H2_SESSION_EV_FRAME_RCVD, 0, "window update");
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+ }
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break;
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case NGHTTP2_RST_STREAM:
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ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, session->c, APLOGNO(03067)
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@@ -404,6 +408,12 @@ static int on_frame_recv_cb(nghttp2_session *ng2s,
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frame->goaway.error_code, NULL);
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}
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break;
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+ case NGHTTP2_SETTINGS:
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+ if (APLOGctrace2(session->c)) {
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+ ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, session->c,
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+ H2_SSSN_MSG(session, "SETTINGS, len=%ld"), (long)frame->hd.length);
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+ }
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+ break;
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default:
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if (APLOGctrace2(session->c)) {
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char buffer[256];
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@@ -415,7 +425,40 @@ static int on_frame_recv_cb(nghttp2_session *ng2s,
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}
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break;
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}
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- return (APR_SUCCESS == rv)? 0 : NGHTTP2_ERR_PROTO;
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+
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+ if (session->state == H2_SESSION_ST_IDLE) {
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+ /* We received a frame, but session is in state IDLE. That means the frame
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+ * did not really progress any of the (possibly) open streams. It was a meta
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+ * frame, e.g. SETTINGS/WINDOW_UPDATE/unknown/etc.
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+ * Remember: IDLE means we cannot send because either there are no streams open or
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+ * all open streams are blocked on exhausted WINDOWs for outgoing data.
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+ * The more frames we receive that do not change this, the less interested we
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+ * become in serving this connection. This is expressed in increasing "idle_delays".
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+ * Eventually, the connection will timeout and we'll close it. */
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+ session->idle_frames = H2MIN(session->idle_frames + 1, session->frames_received);
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+ ap_log_cerror( APLOG_MARK, APLOG_TRACE2, 0, session->c,
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+ H2_SSSN_MSG(session, "session has %ld idle frames"),
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+ (long)session->idle_frames);
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+ if (session->idle_frames > 10) {
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+ apr_size_t busy_frames = H2MAX(session->frames_received - session->idle_frames, 1);
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+ int idle_ratio = (int)(session->idle_frames / busy_frames);
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+ if (idle_ratio > 100) {
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+ session->idle_delay = apr_time_from_msec(H2MIN(1000, idle_ratio));
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+ }
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+ else if (idle_ratio > 10) {
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+ session->idle_delay = apr_time_from_msec(10);
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+ }
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+ else if (idle_ratio > 1) {
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+ session->idle_delay = apr_time_from_msec(1);
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+ }
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+ else {
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+ session->idle_delay = 0;
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+ }
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+ }
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+ }
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+
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+ if (APR_SUCCESS != rv) return NGHTTP2_ERR_PROTO;
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+ return 0;
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}
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static int h2_session_continue_data(h2_session *session) {
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@@ -1603,23 +1646,57 @@ static void update_child_status(h2_session *session, int status, const char *msg
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static void transit(h2_session *session, const char *action, h2_session_state nstate)
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{
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+ apr_time_t timeout;
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+ int ostate, loglvl;
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+ const char *s;
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+
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if (session->state != nstate) {
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- int loglvl = APLOG_DEBUG;
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- if ((session->state == H2_SESSION_ST_BUSY && nstate == H2_SESSION_ST_WAIT)
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- || (session->state == H2_SESSION_ST_WAIT && nstate == H2_SESSION_ST_BUSY)){
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+ ostate = session->state;
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+ session->state = nstate;
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+
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+ loglvl = APLOG_DEBUG;
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+ if ((ostate == H2_SESSION_ST_BUSY && nstate == H2_SESSION_ST_WAIT)
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+ || (ostate == H2_SESSION_ST_WAIT && nstate == H2_SESSION_ST_BUSY)){
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loglvl = APLOG_TRACE1;
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}
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ap_log_cerror(APLOG_MARK, loglvl, 0, session->c,
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H2_SSSN_LOG(APLOGNO(03078), session,
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"transit [%s] -- %s --> [%s]"),
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- h2_session_state_str(session->state), action,
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+ h2_session_state_str(ostate), action,
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h2_session_state_str(nstate));
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- session->state = nstate;
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+
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switch (session->state) {
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case H2_SESSION_ST_IDLE:
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- update_child_status(session, (session->open_streams == 0?
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- SERVER_BUSY_KEEPALIVE
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- : SERVER_BUSY_READ), "idle");
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+ if (!session->remote.emitted_count) {
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+ /* on fresh connections, with async mpm, do not return
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+ * to mpm for a second. This gives the first request a better
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+ * chance to arrive (und connection leaving IDLE state).
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+ * If we return to mpm right away, this connection has the
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+ * same chance of being cleaned up by the mpm as connections
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+ * that already served requests - not fair. */
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+ session->idle_sync_until = apr_time_now() + apr_time_from_sec(1);
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+ s = "timeout";
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+ timeout = H2MAX(session->s->timeout, session->s->keep_alive_timeout);
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+ update_child_status(session, SERVER_BUSY_READ, "idle");
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+ ap_log_cerror(APLOG_MARK, APLOG_TRACE1, 0, session->c,
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+ H2_SSSN_LOG("", session, "enter idle, timeout = %d sec"),
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+ (int)apr_time_sec(H2MAX(session->s->timeout, session->s->keep_alive_timeout)));
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+ }
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+ else if (session->open_streams) {
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+ s = "timeout";
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+ timeout = session->s->keep_alive_timeout;
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+ update_child_status(session, SERVER_BUSY_KEEPALIVE, "idle");
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+ }
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+ else {
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+ /* normal keepalive setup */
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+ s = "keepalive";
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+ timeout = session->s->keep_alive_timeout;
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+ update_child_status(session, SERVER_BUSY_KEEPALIVE, "idle");
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+ }
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+ session->idle_until = apr_time_now() + timeout;
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+ ap_log_cerror(APLOG_MARK, APLOG_TRACE1, 0, session->c,
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+ H2_SSSN_LOG("", session, "enter idle, %s = %d sec"),
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+ s, (int)apr_time_sec(timeout));
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break;
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case H2_SESSION_ST_DONE:
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update_child_status(session, SERVER_CLOSING, "done");
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@@ -1726,8 +1803,6 @@ static void h2_session_ev_no_io(h2_session *session, int arg, const char *msg)
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* This means we only wait for WINDOW_UPDATE from the
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* client and can block on READ. */
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transit(session, "no io (flow wait)", H2_SESSION_ST_IDLE);
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- session->idle_until = apr_time_now() + session->s->timeout;
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- session->keep_sync_until = session->idle_until;
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/* Make sure we have flushed all previously written output
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* so that the client will react. */
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if (h2_conn_io_flush(&session->io) != APR_SUCCESS) {
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@@ -1738,12 +1813,7 @@ static void h2_session_ev_no_io(h2_session *session, int arg, const char *msg)
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}
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else if (session->local.accepting) {
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/* When we have no streams, but accept new, switch to idle */
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- apr_time_t now = apr_time_now();
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transit(session, "no io (keepalive)", H2_SESSION_ST_IDLE);
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- session->idle_until = (session->remote.emitted_count?
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- session->s->keep_alive_timeout :
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- session->s->timeout) + now;
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- session->keep_sync_until = now + apr_time_from_sec(1);
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}
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else {
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/* We are no longer accepting new streams and there are
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@@ -1758,12 +1828,25 @@ static void h2_session_ev_no_io(h2_session *session, int arg, const char *msg)
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}
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}
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-static void h2_session_ev_data_read(h2_session *session, int arg, const char *msg)
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+static void h2_session_ev_frame_rcvd(h2_session *session, int arg, const char *msg)
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+{
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+ switch (session->state) {
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+ case H2_SESSION_ST_IDLE:
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+ case H2_SESSION_ST_WAIT:
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+ transit(session, "frame received", H2_SESSION_ST_BUSY);
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+ break;
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+ default:
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+ /* nop */
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+ break;
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+ }
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+}
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+
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+static void h2_session_ev_stream_change(h2_session *session, int arg, const char *msg)
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{
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switch (session->state) {
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case H2_SESSION_ST_IDLE:
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case H2_SESSION_ST_WAIT:
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- transit(session, "data read", H2_SESSION_ST_BUSY);
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+ transit(session, "stream change", H2_SESSION_ST_BUSY);
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break;
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default:
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/* nop */
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@@ -1803,16 +1886,6 @@ static void h2_session_ev_pre_close(h2_session *session, int arg, const char *ms
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static void ev_stream_open(h2_session *session, h2_stream *stream)
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{
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h2_iq_append(session->in_process, stream->id);
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- switch (session->state) {
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- case H2_SESSION_ST_IDLE:
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- if (session->open_streams == 1) {
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- /* enter timeout, since we have a stream again */
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- session->idle_until = (session->s->timeout + apr_time_now());
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- }
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- break;
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- default:
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- break;
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- }
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}
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static void ev_stream_closed(h2_session *session, h2_stream *stream)
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@@ -1825,11 +1898,6 @@ static void ev_stream_closed(h2_session *session, h2_stream *stream)
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}
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switch (session->state) {
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case H2_SESSION_ST_IDLE:
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- if (session->open_streams == 0) {
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- /* enter keepalive timeout, since we no longer have streams */
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- session->idle_until = (session->s->keep_alive_timeout
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- + apr_time_now());
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- }
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break;
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default:
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break;
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@@ -1887,6 +1955,7 @@ static void on_stream_state_enter(void *ctx, h2_stream *stream)
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default:
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break;
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}
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+ dispatch_event(session, H2_SESSION_EV_STREAM_CHANGE, 0, "stream state change");
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}
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static void on_stream_event(void *ctx, h2_stream *stream,
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@@ -1945,8 +2014,8 @@ static void dispatch_event(h2_session *session, h2_session_event_t ev,
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case H2_SESSION_EV_NO_IO:
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h2_session_ev_no_io(session, arg, msg);
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break;
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- case H2_SESSION_EV_DATA_READ:
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- h2_session_ev_data_read(session, arg, msg);
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+ case H2_SESSION_EV_FRAME_RCVD:
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+ h2_session_ev_frame_rcvd(session, arg, msg);
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break;
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case H2_SESSION_EV_NGH2_DONE:
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h2_session_ev_ngh2_done(session, arg, msg);
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@@ -1957,6 +2026,9 @@ static void dispatch_event(h2_session *session, h2_session_event_t ev,
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case H2_SESSION_EV_PRE_CLOSE:
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h2_session_ev_pre_close(session, arg, msg);
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break;
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+ case H2_SESSION_EV_STREAM_CHANGE:
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+ h2_session_ev_stream_change(session, arg, msg);
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+ break;
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default:
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ap_log_cerror(APLOG_MARK, APLOG_TRACE1, 0, session->c,
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H2_SSSN_MSG(session, "unknown event %d"), ev);
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@@ -1990,13 +2062,15 @@ apr_status_t h2_session_process(h2_session *session, int async)
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apr_status_t status = APR_SUCCESS;
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conn_rec *c = session->c;
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int rv, mpm_state, trace = APLOGctrace3(c);
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-
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+ apr_time_t now;
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+
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if (trace) {
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ap_log_cerror( APLOG_MARK, APLOG_TRACE3, status, c,
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H2_SSSN_MSG(session, "process start, async=%d"), async);
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}
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while (session->state != H2_SESSION_ST_DONE) {
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+ now = apr_time_now();
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session->have_read = session->have_written = 0;
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if (session->local.accepting
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@@ -2034,39 +2108,42 @@ apr_status_t h2_session_process(h2_session *session, int async)
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break;
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case H2_SESSION_ST_IDLE:
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- /* We trust our connection into the default timeout/keepalive
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- * handling of the core filters/mpm iff:
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- * - keep_sync_until is not set
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- * - we have an async mpm
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- * - we have no open streams to process
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- * - we are not sitting on a Upgrade: request
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- * - we already have seen at least one request
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- */
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- if (!session->keep_sync_until && async && !session->open_streams
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- && !session->r && session->remote.emitted_count) {
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+ if (session->idle_until && (apr_time_now() + session->idle_delay) > session->idle_until) {
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+ ap_log_cerror( APLOG_MARK, APLOG_TRACE1, status, c,
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+ H2_SSSN_MSG(session, "idle, timeout reached, closing"));
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+ if (session->idle_delay) {
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+ apr_table_setn(session->c->notes, "short-lingering-close", "1");
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+ }
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+ dispatch_event(session, H2_SESSION_EV_CONN_TIMEOUT, 0, "timeout");
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+ goto out;
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+ }
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+
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+ if (session->idle_delay) {
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+ /* we are less interested in spending time on this connection */
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+ ap_log_cerror( APLOG_MARK, APLOG_TRACE2, status, c,
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+ H2_SSSN_MSG(session, "session is idle (%ld ms), idle wait %ld sec left"),
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+ (long)apr_time_as_msec(session->idle_delay),
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+ (long)apr_time_sec(session->idle_until - now));
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+ apr_sleep(session->idle_delay);
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+ session->idle_delay = 0;
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+ }
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+
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+ h2_conn_io_flush(&session->io);
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+ if (async && !session->r && (now > session->idle_sync_until)) {
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if (trace) {
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ap_log_cerror(APLOG_MARK, APLOG_TRACE3, status, c,
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H2_SSSN_MSG(session,
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"nonblock read, %d streams open"),
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session->open_streams);
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}
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- h2_conn_io_flush(&session->io);
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status = h2_session_read(session, 0);
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if (status == APR_SUCCESS) {
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session->have_read = 1;
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- dispatch_event(session, H2_SESSION_EV_DATA_READ, 0, NULL);
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}
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- else if (APR_STATUS_IS_EAGAIN(status)
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- || APR_STATUS_IS_TIMEUP(status)) {
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- if (apr_time_now() > session->idle_until) {
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- dispatch_event(session,
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- H2_SESSION_EV_CONN_TIMEOUT, 0, NULL);
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- }
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- else {
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- status = APR_EAGAIN;
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- goto out;
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- }
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+ else if (APR_STATUS_IS_EAGAIN(status) || APR_STATUS_IS_TIMEUP(status)) {
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+ status = APR_EAGAIN;
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+ goto out;
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}
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else {
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ap_log_cerror(APLOG_MARK, APLOG_DEBUG, status, c,
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@@ -2078,7 +2155,6 @@ apr_status_t h2_session_process(h2_session *session, int async)
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}
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else {
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/* make certain, we send everything before we idle */
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- h2_conn_io_flush(&session->io);
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if (trace) {
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ap_log_cerror(APLOG_MARK, APLOG_TRACE3, status, c,
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H2_SSSN_MSG(session,
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@@ -2090,7 +2166,6 @@ apr_status_t h2_session_process(h2_session *session, int async)
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*/
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status = h2_mplx_idle(session->mplx);
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if (status == APR_EAGAIN) {
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- dispatch_event(session, H2_SESSION_EV_DATA_READ, 0, NULL);
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break;
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}
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else if (status != APR_SUCCESS) {
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@@ -2101,33 +2176,11 @@ apr_status_t h2_session_process(h2_session *session, int async)
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status = h2_session_read(session, 1);
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if (status == APR_SUCCESS) {
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session->have_read = 1;
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- dispatch_event(session, H2_SESSION_EV_DATA_READ, 0, NULL);
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}
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else if (status == APR_EAGAIN) {
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/* nothing to read */
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}
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else if (APR_STATUS_IS_TIMEUP(status)) {
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- apr_time_t now = apr_time_now();
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- if (now > session->keep_sync_until) {
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- /* if we are on an async mpm, now is the time that
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- * we may dare to pass control to it. */
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- session->keep_sync_until = 0;
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- }
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- if (now > session->idle_until) {
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- if (trace) {
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- ap_log_cerror(APLOG_MARK, APLOG_TRACE3, status, c,
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- H2_SSSN_MSG(session,
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- "keepalive timeout"));
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- }
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- dispatch_event(session,
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- H2_SESSION_EV_CONN_TIMEOUT, 0, "timeout");
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- }
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- else if (trace) {
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- ap_log_cerror(APLOG_MARK, APLOG_TRACE3, status, c,
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- H2_SSSN_MSG(session,
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- "keepalive, %f sec left"),
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- (session->idle_until - now) / 1000000.0f);
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- }
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/* continue reading handling */
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}
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else if (APR_STATUS_IS_ECONNABORTED(status)
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@@ -2145,6 +2198,18 @@ apr_status_t h2_session_process(h2_session *session, int async)
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dispatch_event(session, H2_SESSION_EV_CONN_ERROR, 0, "error");
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}
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}
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+ if (nghttp2_session_want_write(session->ngh2)) {
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+ ap_update_child_status(session->c->sbh, SERVER_BUSY_WRITE, NULL);
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+ status = h2_session_send(session);
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+ if (status == APR_SUCCESS) {
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+ status = h2_conn_io_flush(&session->io);
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+ }
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+ if (status != APR_SUCCESS) {
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+ dispatch_event(session, H2_SESSION_EV_CONN_ERROR,
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+ H2_ERR_INTERNAL_ERROR, "writing");
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+ break;
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+ }
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+ }
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break;
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case H2_SESSION_ST_BUSY:
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@@ -2154,7 +2219,6 @@ apr_status_t h2_session_process(h2_session *session, int async)
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status = h2_session_read(session, 0);
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if (status == APR_SUCCESS) {
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session->have_read = 1;
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- dispatch_event(session, H2_SESSION_EV_DATA_READ, 0, NULL);
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}
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else if (status == APR_EAGAIN) {
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/* nothing to read */
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@@ -2218,7 +2282,7 @@ apr_status_t h2_session_process(h2_session *session, int async)
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session->iowait);
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if (status == APR_SUCCESS) {
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session->wait_us = 0;
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- dispatch_event(session, H2_SESSION_EV_DATA_READ, 0, NULL);
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+ dispatch_event(session, H2_SESSION_EV_STREAM_CHANGE, 0, NULL);
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}
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else if (APR_STATUS_IS_TIMEUP(status)) {
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/* go back to checking all inputs again */
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diff --git a/modules/http2/h2_session.h b/modules/http2/h2_session.h
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index 486938b0..df2a8624 100644
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--- a/modules/http2/h2_session.h
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+++ b/modules/http2/h2_session.h
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@@ -66,10 +66,11 @@ typedef enum {
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H2_SESSION_EV_PROTO_ERROR, /* protocol error */
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H2_SESSION_EV_CONN_TIMEOUT, /* connection timeout */
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H2_SESSION_EV_NO_IO, /* nothing has been read or written */
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- H2_SESSION_EV_DATA_READ, /* connection data has been read */
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+ H2_SESSION_EV_FRAME_RCVD, /* a frame has been received */
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H2_SESSION_EV_NGH2_DONE, /* nghttp2 wants neither read nor write anything */
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H2_SESSION_EV_MPM_STOPPING, /* the process is stopping */
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H2_SESSION_EV_PRE_CLOSE, /* connection will close after this */
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+ H2_SESSION_EV_STREAM_CHANGE, /* a stream (state/input/output) changed */
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} h2_session_event_t;
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typedef struct h2_session {
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@@ -118,7 +119,9 @@ typedef struct h2_session {
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apr_size_t max_stream_mem; /* max buffer memory for a single stream */
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apr_time_t idle_until; /* Time we shut down due to sheer boredom */
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- apr_time_t keep_sync_until; /* Time we sync wait until passing to async mpm */
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+ apr_time_t idle_sync_until; /* Time we sync wait until keepalive handling kicks in */
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+ apr_size_t idle_frames; /* number of rcvd frames that kept session in idle state */
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+ apr_interval_time_t idle_delay; /* Time we delay processing rcvd frames in idle state */
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apr_bucket_brigade *bbtmp; /* brigade for keeping temporary data */
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struct apr_thread_cond_t *iowait; /* our cond when trywaiting for data */
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