introduce api for unthrottle all connections of protocol

Signed-off-by: Andy Green <andy.green@linaro.org>

changelog

@@ -20,6 +20,15 @@ User api additions
 	after the service call... if it's still nonzero, the descriptor
 	belongs to you and you need to take care of it.
 
+ - libwebsocket_rx_flow_allow_all_protocol(protocol) will unthrottle all
+ 	connections with the established protocol.  It's designed to be
+	called from user server code when it sees it can accept more input
+	and may have throttled connections using the server rx flow apis
+	while it was unable to accept any other input  The user server code
+	then does not have to try to track while connections it choked, this
+	will free up all of them in one call.
+
+
 User api changes
 ----------------
 

lib/libwebsockets.c

@@ -1579,6 +1579,33 @@ libwebsocket_rx_flow_control(struct libwebsocket *wsi, int enable)
 	return 0;
 }
 
+/**
+ * libwebsocket_rx_flow_allow_all_protocol() - Allow all connections with this protocol to receive
+ *
+ * When the user server code realizes it can accept more input, it can
+ * call this to have the RX flow restriction removed from all connections using
+ * the given protocol.
+ *
+ * @protocol:	all connections using this protocol will be allowed to receive
+ */
+
+void
+libwebsocket_rx_flow_allow_all_protocol(
+				const struct libwebsocket_protocols *protocol)
+{
+	struct libwebsocket_context *context = protocol->owning_server;
+	int n;
+	struct libwebsocket *wsi;
+
+	for (n = 0; n < context->fds_count; n++) {
+		wsi = context->lws_lookup[context->fds[n].fd];
+		if (!wsi)
+			continue;
+		if (wsi->protocol == protocol)
+			libwebsocket_rx_flow_control(wsi, LWS_RXFLOW_ALLOW);
+	}
+}
+
 
 /**
  * libwebsocket_canonical_hostname() - returns this host's hostname

lib/libwebsockets.h

@@ -888,6 +888,10 @@ libwebsocket_get_reserved_bits(struct libwebsocket *wsi);
 LWS_EXTERN int
 libwebsocket_rx_flow_control(struct libwebsocket *wsi, int enable);
 
+LWS_EXTERN void
+libwebsocket_rx_flow_allow_all_protocol(
+				const struct libwebsocket_protocols *protocol);
+
 LWS_EXTERN size_t
 libwebsockets_remaining_packet_payload(struct libwebsocket *wsi);
 

libwebsockets-api-doc.html

@@ -273,6 +273,23 @@ If the output side of a server process becomes choked, this allows flow
 control for the input side.
 </blockquote>
 <hr>
+<h2>libwebsocket_rx_flow_allow_all_protocol - Allow all connections with this protocol to receive</h2>
+<i>void</i>
+<b>libwebsocket_rx_flow_allow_all_protocol</b>
+(<i>const struct libwebsocket_protocols *</i> <b>protocol</b>)
+<h3>Arguments</h3>
+<dl>
+<dt><b>protocol</b>
+<dd>all connections using this protocol will be allowed to receive
+</dl>
+<h3>Description</h3>
+<blockquote>
+<p>
+When the user server code realizes it can accept more input, it can
+call this to have the RX flow restriction removed from all connections using
+the given protocol.
+</blockquote>
+<hr>
 <h2>libwebsocket_canonical_hostname - returns this host's hostname</h2>
 <i>const char *</i>
 <b>libwebsocket_canonical_hostname</b>

test-server/test-server.c

@@ -446,9 +446,6 @@ struct a_message {
 static struct a_message ringbuffer[MAX_MESSAGE_QUEUE];
 static int ringbuffer_head;
 
-static struct libwebsocket *wsi_choked[20];
-static int num_wsi_choked;
-
 static int
 callback_lws_mirror(struct libwebsocket_context *context,
 			struct libwebsocket *wsi,
@@ -497,11 +494,10 @@ callback_lws_mirror(struct libwebsocket_context *context,
 				pss->ringbuffer_tail++;
 
 			if (((ringbuffer_head - pss->ringbuffer_tail) &
-				  (MAX_MESSAGE_QUEUE - 1)) == (MAX_MESSAGE_QUEUE - 15)) {
+				  (MAX_MESSAGE_QUEUE - 1)) == (MAX_MESSAGE_QUEUE - 15))
-				for (n = 0; n < num_wsi_choked; n++)
+				libwebsocket_rx_flow_allow_all_protocol(
-					libwebsocket_rx_flow_control(wsi_choked[n], 1);
+					       libwebsockets_get_protocol(wsi));
-				num_wsi_choked = 0;
+
-			}
 			// lwsl_debug("tx fifo %d\n", (ringbuffer_head - pss->ringbuffer_tail) & (MAX_MESSAGE_QUEUE - 1));
 
 			if (lws_send_pipe_choked(wsi)) {
@@ -543,11 +539,8 @@ callback_lws_mirror(struct libwebsocket_context *context,
 			goto done;
 
 choke:
-		if (num_wsi_choked < sizeof wsi_choked / sizeof wsi_choked[0]) {
 		lwsl_debug("LWS_CALLBACK_RECEIVE: throttling %p\n", wsi);
 		libwebsocket_rx_flow_control(wsi, 0);
-			wsi_choked[num_wsi_choked++] = wsi;
-		}
 
 //		lwsl_debug("rx fifo %d\n", (ringbuffer_head - pss->ringbuffer_tail) & (MAX_MESSAGE_QUEUE - 1));
 done: