sse: drop the ah when the sse connection starts

include/libwebsockets/lws-http.h

@@ -653,6 +653,18 @@ lws_http_redirect(struct lws *wsi, int code, const unsigned char *loc, int len,
 LWS_VISIBLE LWS_EXTERN int LWS_WARN_UNUSED_RESULT
 lws_http_transaction_completed(struct lws *wsi);
 
+/**
+ * lws_http_headers_detach() - drop the associated headers storage and allow
+ *				it to be reused by another connection
+ * \param wsi:	http connection
+ *
+ *	Returns 1 if the HTTP connection must close now
+ *	Returns 0 and resets connection to wait for new HTTP header /
+ *	  transaction if possible
+ */
+LWS_VISIBLE LWS_EXTERN int
+lws_http_headers_detach(struct lws *wsi);
+
 /**
  * lws_http_compression_apply() - apply an http compression transform
  *

lib/roles/http/header.c

@@ -526,4 +526,8 @@ lws_http_compression_apply(struct lws *wsi, const char *name,
 }
 #endif
 
-
+int
+lws_http_headers_detach(struct lws *wsi)
+{
+	return lws_header_table_detach(wsi, 0);
+}

minimal-examples/http-server/minimal-http-server-sse-ring/minimal-http-server-sse-ring.c

@@ -215,6 +215,18 @@ callback_sse(struct lws *wsi, enum lws_callback_reasons reason, void *user,
 		pss->tail = lws_ring_get_oldest_tail(vhd->ring);
 		pss->wsi = wsi;
 
+		/*
+		 * Drop the ah that contains the headers associated with
+		 * this connection... ah are a scarce resource, if we don't
+		 * drop it lws will forcibly drop the whole connection to free
+		 * the ah after 5 minutes or so.
+		 *
+		 * If the content of any http headers are important to you for
+		 * deciding what to send, copy them out to the pss before
+		 * doing the below to drop the ah.
+		 */
+		lws_http_headers_detach(wsi);
+
 		/* Unlike a normal http connection, we don't want any specific
 		 * timeout.  We want to stay up until the client drops us */
 

minimal-examples/http-server/minimal-http-server-sse/minimal-http-server-sse.c

@@ -70,6 +70,18 @@ callback_sse(struct lws *wsi, enum lws_callback_reasons reason, void *user,
 
 		lws_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
 
+		/*
+		 * Drop the ah that contains the headers associated with
+		 * this connection... ah are a scarce resource, if we don't
+		 * drop it lws will forcibly drop the whole connection to free
+		 * the ah after 5 minutes or so.
+		 *
+		 * If the content of any http headers are important to you for
+		 * deciding what to send, copy them out to the pss before
+		 * doing the below to drop the ah.
+		 */
+		lws_http_headers_detach(wsi);
+
 		/* write the body separately */
 
 		lws_callback_on_writable(wsi);