Extend the socket callbacks in event to allow a timeout on the I/O callback.

When a socket callback has a timeout, an associated timer event is used to 
remove the sockets from the pollset and call a timeout function.

* This includes a noteworthy change to the main event loop. Previously,
we would call epoll, then process the timer events, then iterate through the
poll results. After this patch, the timer events are processed before the poll()
a _non-queued_ action can change the pollset conents (a users timed callback
function conversely could easily sit in a queue while the main thread continues
down into epoll)

* timer events can now have sockets associated with them, those sockets are 
removed from the pollset when the timer event fires w/o a queue to the worker.

* timer events now have a canceled flag that can be toggled without locking
the timer list. 

* Drop the severity of some wstunnel messages from DEBUG to TRACE1

* Lift the restriction on using asynchronous websockets connections but having
an idle timeout



git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1593857 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 24 insertions, 1 deletions

diff --git a/include/ap_mpm.h b/include/ap_mpm.h
index ba7a95b0f5..d851f35582 100644
--- a/include/ap_mpm.h
+++ b/include/ap_mpm.h
@@ -213,7 +213,6 @@ AP_DECLARE(apr_status_t) ap_mpm_register_timed_callback(apr_time_t t,
  * APR_ENOTIMPL if no asynch support, or an apr_pollset_add error.
  * @remark When activity is found on any 1 socket in the list, all are removed 
  * from the pollset and only 1 callback is issued.
- * @fn apr_status_t ap_mpm_register_socket_callback(apr_socket_t **s, apr_pool_t *p, int for_read, ap_mpm_callback_fn_t *cbfn, void *baton)
  */
 
 AP_DECLARE(apr_status_t) ap_mpm_register_socket_callback(apr_socket_t **s,
@@ -221,6 +220,30 @@ AP_DECLARE(apr_status_t) ap_mpm_register_socket_callback(apr_socket_t **s,
                                                          int for_read, 
                                                          ap_mpm_callback_fn_t *cbfn,
                                                          void *baton);
+ /**
+ * Register a callback on the readability or writability on a group of sockets, with a timeout
+ * @param s Null-terminated list of sockets
+ * @param p pool for use between registration and callback
+ * @param for_read Whether the sockets are monitored for read or writability
+ * @param cbfn The callback function
+ * @param tofn The callback function if the timeout expires
+ * @param baton userdata for the callback function
+ * @param timeout timeout for I/O in microseconds, unlimited if <= 0
+ * @return APR_SUCCESS if all sockets could be added to a pollset, 
+ * APR_ENOTIMPL if no asynch support, or an apr_pollset_add error.
+ * @remark When activity is found on any 1 socket in the list, all are removed 
+ * from the pollset and only 1 callback is issued. 
+ * @remark For each call, only one of tofn or cbfn will be called, never both.
+ */
+
+AP_DECLARE(apr_status_t) ap_mpm_register_socket_callback_timeout(apr_socket_t **s,
+                                                         apr_pool_t *p,
+                                                         int for_read, 
+                                                         ap_mpm_callback_fn_t *cbfn,
+                                                         ap_mpm_callback_fn_t *tofn,
+                                                         void *baton,
+                                                         apr_time_t timeout);
+
 
 AP_DECLARE(apr_status_t) ap_mpm_unregister_socket_callback(apr_socket_t **s, 
                                                            apr_pool_t *p);