http: mounts: LWSMPRO_NO_MOUNT

Provide a way to apply exception mount urls that exist on top of a larger
mount, but provide an exception which enforces the url to not be serviced
by the mount code, but by whatever dynamic handler is in place.

include/libwebsockets/lws-context-vhost.h

@@ -1294,7 +1294,8 @@ enum lws_mount_protocols {
 	LWSMPRO_CGI		= 3, /**< pass to CGI to handle */
 	LWSMPRO_REDIR_HTTP	= 4, /**< redirect to http:// url */
 	LWSMPRO_REDIR_HTTPS	= 5, /**< redirect to https:// url */
-	LWSMPRO_CALLBACK	= 6, /**< hand by named protocol's callback */
+	LWSMPRO_CALLBACK	= 6, /**< handle by named protocol's callback */
+	LWSMPRO_NO_MOUNT        = 7, /**< matches fall back to no match processing */
 };
 
 /** enum lws_authentication_mode
@@ -1357,5 +1358,8 @@ struct lws_http_mount {
 	 */
 };
 
+LWS_VISIBLE LWS_EXTERN void
+lws_vhost_set_mounts(struct lws_vhost *v, const struct lws_http_mount *mounts);
+
 ///@}
 ///@}

lib/core-net/close.c

@@ -120,6 +120,7 @@ __lws_reset_wsi(struct lws *wsi)
 	}
 #endif
 	wsi->retry = 0;
+	wsi->mount_hit = 0;
 
 #if defined(LWS_WITH_CLIENT)
 	lws_dll2_remove(&wsi->dll2_cli_txn_queue);

lib/core-net/private-lib-core-net.h

@@ -812,6 +812,7 @@ struct lws {
 	unsigned int			file_desc:1;
 	unsigned int			conn_validity_wakesuspend:1;
 	unsigned int			dns_reachability:1;
+	unsigned int			mount_hit:1;
 
 	unsigned int			could_have_pending:1; /* detect back-to-back writes */
 	unsigned int			outer_will_close:1;

lib/core-net/vhost.c

@@ -1078,6 +1078,14 @@ early_bail:
 	return NULL;
 }
 
+void
+lws_vhost_set_mounts(struct lws_vhost *vh, const struct lws_http_mount *mounts)
+{
+#if defined(LWS_ROLE_H1) || defined(LWS_ROLE_H2)
+        vh->http.mount_list = mounts;
+#endif
+}
+
 int
 lws_init_vhost_client_ssl(const struct lws_context_creation_info *info,
 			  struct lws_vhost *vhost)

lib/roles/http/server/server.c

@@ -955,6 +955,9 @@ lws_find_mount(struct lws *wsi, const char *uri_ptr, int uri_len)
 			lws_metrics_tag_wsi_add(wsi, "mnt", hm->mountpoint);
 #endif
 
+			if (hm->origin_protocol == LWSMPRO_NO_MOUNT)
+				return NULL;
+
 			if (hm->origin_protocol == LWSMPRO_CALLBACK ||
 			    ((hm->origin_protocol == LWSMPRO_CGI ||
 			     lws_hdr_total_length(wsi, WSI_TOKEN_GET_URI) ||
@@ -1782,6 +1785,7 @@ lws_http_action(struct lws *wsi)
 
 	/* can we serve it from the mount list? */
 
+	wsi->mount_hit = 0;
 	hit = lws_find_mount(wsi, uri_ptr, uri_len);
 	if (!hit) {
 		/* deferred cleanup and reset to protocols[0] */
@@ -1800,6 +1804,8 @@ lws_http_action(struct lws *wsi)
 		goto after;
 	}
 
+	wsi->mount_hit = 1;
+
 #if defined(LWS_WITH_FILE_OPS)
 	s = uri_ptr + hit->mountpoint_len;
 #endif

lib/secure-streams/protocols/ss-h1.c

@@ -1071,6 +1071,9 @@ malformed:
 		if (!h)
 			return -1;
 
+		if (h->wsi && h->wsi->mount_hit)
+			break;
+
 		lwsl_info("%s: LWS_CALLBACK_HTTP\n", __func__);
 		{