commit 39affe6c5629b78e418f33787ec7a9556b287832
parent 5b45f52e777fafb65fe9e4a53d202e38e3accdc9
Author: Christian Grothoff <christian@grothoff.org>
Date: Sun, 31 Mar 2013 18:28:43 +0000
adding MHD_run_from_select to API
Diffstat:
5 files changed, 146 insertions(+), 32 deletions(-)
diff --git a/ChangeLog b/ChangeLog
@@ -1,3 +1,8 @@
+Sun Mar 31 20:27:48 CEST 2013
+ Adding new API call 'MHD_run_from_select' to allow programs
+ running in 'external select mode' to reduce the number of
+ 'select' calls by a factor of two. -CG
+
Sun Mar 31 20:03:48 CEST 2013
Performance improvements, updated documentation.
Make better use of available memory pool memory for
diff --git a/doc/libmicrohttpd.texi b/doc/libmicrohttpd.texi
@@ -1095,11 +1095,53 @@ Shutdown an HTTP daemon.
Run webserver operations (without blocking unless in client callbacks).
This method should be called by clients in combination with
@code{MHD_get_fdset()} if the client-controlled @code{select}-method is used.
+@cindex select
+@cindex poll
+
+This function will work for external @code{poll} and @code{select} mode.
+However, if using external @code{select} mode, you may want to
+instead use @code{MHD_run_from_select}, as it is more efficient.
+
+@table @var
+@item daemon
+daemon to process connections of
+@end table
Return @code{MHD_YES} on success, @code{MHD_NO} if this daemon was not
started with the right options for this call.
@end deftypefun
+@deftypefun int MHD_run_from_select (struct MHD_Daemon *daemon, const fd_set *read_fd_set, const fd_set *write_fd_set, const fd_set *except_fd_set)
+Run webserver operations given sets of ready socket handles.
+@cindex select
+
+This method should be called by clients in combination with
+@code{MHD_get_fdset} if the client-controlled (external)
+select method is used.
+
+You can use this function instead of @code{MHD_run} if you called
+@code{select} on the result from @code{MHD_get_fdset}. File descriptors in
+the sets that are not controlled by MHD will be ignored. Calling
+this function instead of @code{MHD_run} is more efficient as MHD will
+not have to call @code{select} again to determine which operations are
+ready.
+
+@table @var
+@item daemon
+daemon to process connections of
+@item read_fd_set
+set of descriptors that must be ready for reading without blocking
+@item write_fd_set
+set of descriptors that must be ready for writing without blocking
+@item except_fd_set
+ignored, can be NULL
+@end table
+
+Return @code{MHD_YES} on success, @code{MHD_NO} on serious internal
+errors.
+
+@end deftypefun
+
@deftypefun void MHD_add_connection (struct MHD_Daemon *daemon, int client_socket, const struct sockaddr *addr, socklen_t addrlen)
Add another client connection to the set of connections
diff --git a/src/daemon/EXPORT.sym b/src/daemon/EXPORT.sym
@@ -4,6 +4,7 @@ MHD_stop_daemon
MHD_get_fdset
MHD_get_timeout
MHD_run
+MHD_run_from_select
MHD_get_connection_values
MHD_set_connection_value
MHD_lookup_connection_value
diff --git a/src/daemon/daemon.c b/src/daemon/daemon.c
@@ -1329,7 +1329,66 @@ MHD_get_timeout (struct MHD_Daemon *daemon,
/**
- * Main select call.
+ * Run webserver operations. This method should be called by clients
+ * in combination with MHD_get_fdset if the client-controlled select
+ * method is used.
+ *
+ * You can use this function instead of "MHD_run" if you called
+ * 'select' on the result from "MHD_get_fdset". File descriptors in
+ * the sets that are not controlled by MHD will be ignored. Calling
+ * this function instead of "MHD_run" is more efficient as MHD will
+ * not have to call 'select' again to determine which operations are
+ * ready.
+ *
+ * @param daemon daemon to run select loop for
+ * @param read_fd_set read set
+ * @param write_fd_set write set
+ * @param except_fd_set except set (not used, can be NULL)
+ * @return MHD_NO on serious errors, MHD_YES on success
+ */
+int
+MHD_run_from_select (struct MHD_Daemon *daemon,
+ const fd_set *read_fd_set,
+ const fd_set *write_fd_set,
+ const fd_set *except_fd_set)
+{
+ int ds;
+ struct MHD_Connection *pos;
+ struct MHD_Connection *next;
+
+ /* select connection thread handling type */
+ if ( (-1 != (ds = daemon->socket_fd)) &&
+ (FD_ISSET (ds, read_fd_set)) )
+ MHD_accept_connection (daemon);
+ if (0 == (daemon->options & MHD_USE_THREAD_PER_CONNECTION))
+ {
+ /* do not have a thread per connection, process all connections now */
+ next = daemon->connections_head;
+ while (NULL != (pos = next))
+ {
+ next = pos->next;
+ ds = pos->socket_fd;
+ if (ds != -1)
+ {
+ if ( (FD_ISSET (ds, read_fd_set))
+#if HTTPS_SUPPORT
+ || (MHD_YES == pos->tls_read_ready)
+#endif
+ )
+ pos->read_handler (pos);
+ if (FD_ISSET (ds, write_fd_set))
+ pos->write_handler (pos);
+ pos->idle_handler (pos);
+ }
+ }
+ }
+ return MHD_YES;
+}
+
+
+/**
+ * Main internal select call. Will compute select sets, call 'select'
+ * and then MHD_run_from_select with the result.
*
* @param daemon daemon to run select loop for
* @param may_block YES if blocking, NO if non-blocking
@@ -1339,8 +1398,6 @@ static int
MHD_select (struct MHD_Daemon *daemon,
int may_block)
{
- struct MHD_Connection *pos;
- struct MHD_Connection *next;
int num_ready;
fd_set rs;
fd_set ws;
@@ -1349,7 +1406,6 @@ MHD_select (struct MHD_Daemon *daemon,
struct timeval timeout;
struct timeval *tv;
MHD_UNSIGNED_LONG_LONG ltimeout;
- int ds;
timeout.tv_sec = 0;
timeout.tv_usec = 0;
@@ -1404,7 +1460,6 @@ MHD_select (struct MHD_Daemon *daemon,
tv = &timeout;
}
num_ready = SELECT (max + 1, &rs, &ws, &es, tv);
-
if (MHD_YES == daemon->shutdown)
return MHD_NO;
if (num_ready < 0)
@@ -1416,33 +1471,7 @@ MHD_select (struct MHD_Daemon *daemon,
#endif
return MHD_NO;
}
- /* select connection thread handling type */
- if ( (-1 != (ds = daemon->socket_fd)) &&
- (FD_ISSET (ds, &rs)) )
- MHD_accept_connection (daemon);
- if (0 == (daemon->options & MHD_USE_THREAD_PER_CONNECTION))
- {
- /* do not have a thread per connection, process all connections now */
- next = daemon->connections_head;
- while (NULL != (pos = next))
- {
- next = pos->next;
- ds = pos->socket_fd;
- if (ds != -1)
- {
- if ( (FD_ISSET (ds, &rs))
-#if HTTPS_SUPPORT
- || (MHD_YES == pos->tls_read_ready)
-#endif
- )
- pos->read_handler (pos);
- if (FD_ISSET (ds, &ws))
- pos->write_handler (pos);
- pos->idle_handler (pos);
- }
- }
- }
- return MHD_YES;
+ return MHD_run_from_select (daemon, &rs, &ws, &es);
}
@@ -1647,6 +1676,10 @@ MHD_poll (struct MHD_Daemon *daemon,
* by clients in combination with MHD_get_fdset
* if the client-controlled select method is used.
*
+ * This function will work for external 'poll' and 'select' mode.
+ * However, if using external 'select' mode, you may want to
+ * instead use 'MHD_run_from_select', as it is more efficient.
+ *
* @return MHD_YES on success, MHD_NO if this
* daemon was not started with the right
* options for this call.
diff --git a/src/include/microhttpd.h b/src/include/microhttpd.h
@@ -1182,6 +1182,14 @@ int MHD_get_timeout (struct MHD_Daemon *daemon,
* by clients in combination with MHD_get_fdset
* if the client-controlled select method is used.
*
+ * This function is a convenience method, which is useful if the
+ * fd_sets from "MHD_get_fdset" were not directly passed to 'select';
+ * with this function, MHD will internally do the appropriate 'select'
+ * call itself again. While it is always safe to call 'MHD_run' (in
+ * external select mode), you should call 'MHD_run_from_select' if
+ * performance is important (as it saves an expensive call to
+ * 'select').
+ *
* @param daemon daemon to run
* @return MHD_YES on success, MHD_NO if this
* daemon was not started with the right
@@ -1191,6 +1199,31 @@ int
MHD_run (struct MHD_Daemon *daemon);
+/**
+ * Run webserver operations. This method should be called by clients
+ * in combination with MHD_get_fdset if the client-controlled select
+ * method is used.
+ *
+ * You can use this function instead of "MHD_run" if you called
+ * 'select' on the result from "MHD_get_fdset". File descriptors in
+ * the sets that are not controlled by MHD will be ignored. Calling
+ * this function instead of "MHD_run" is more efficient as MHD will
+ * not have to call 'select' again to determine which operations are
+ * ready.
+ *
+ * @param daemon daemon to run select loop for
+ * @param read_fd_set read set
+ * @param write_fd_set write set
+ * @param except_fd_set except set (not used, can be NULL)
+ * @return MHD_NO on serious errors, MHD_YES on success
+ */
+int
+MHD_run_from_select (struct MHD_Daemon *daemon,
+ const fd_set *read_fd_set,
+ const fd_set *write_fd_set,
+ const fd_set *except_fd_set);
+
+
/* **************** Connection handling functions ***************** */
/**
