WebSockets: also json-escape strings in state messages

libs/surfaces/websockets/json.cc

@@ -0,0 +1,39 @@
+/*
+ * Copyright (C) 2020 Luciano Iam <lucianito@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the/GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <iomanip>
+#include <sstream>
+
+#include "json.h"
+
+/* adapted from https://stackoverflow.com/questions/7724448/simple-json-string-escape-for-c
+   CC BY-SA 4.0 license */
+std::string
+Json::escape (const std::string &s) {
+    std::ostringstream o;
+
+    for (std::string::const_iterator it = s.begin(); it != s.end(); ++it) {
+        if (*it == '"' || *it == '\\' || ('\x00' <= *it && *it <= '\x1f')) {
+            o << "\\u" << std::hex << std::setw (4) << std::setfill ('0') << static_cast<int>(*it);
+        } else {
+            o << *it;
+        }
+    }
+    
+    return o.str ();
+}

libs/surfaces/websockets/json.h

@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2020 Luciano Iam <lucianito@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the/GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef _ardour_surface_json_h_
+#define _ardour_surface_json_h_
+
+class Json
+{
+public:
+	
+	static std::string escape (const std::string&);
+
+};
+
+#endif // _ardour_surface_json_h_

libs/surfaces/websockets/manifest.cc

@@ -26,6 +26,7 @@
 
 #include "manifest.h"
 #include "resources.h"
+#include "json.h"
 
 static const char* const manifest_filename = "manifest.xml";
 
@@ -76,10 +77,10 @@ SurfaceManifest::to_json ()
 	std::stringstream ss;
 
 	ss << "{"
-		<< "\"path\":\"" << ServerResources::escape_json (Glib::path_get_basename (_path)) << "\""
-		<< ",\"name\":\"" << ServerResources::escape_json (_name) << "\""
-		<< ",\"description\":\"" << ServerResources::escape_json (_description) << "\""
-		<< ",\"version\":\"" << ServerResources::escape_json (_version) << "\""
+		<< "\"path\":\"" << Json::escape (Glib::path_get_basename (_path)) << "\""
+		<< ",\"name\":\"" << Json::escape (_name) << "\""
+		<< ",\"description\":\"" << Json::escape (_description) << "\""
+		<< ",\"version\":\"" << Json::escape (_version) << "\""
 		<< "}";
 
 	return ss.str ();

libs/surfaces/websockets/message.cc

@@ -26,6 +26,7 @@
 #include <sstream>
 
 #include "message.h"
+#include "json.h"
 
 // JSON does not support Infinity or NaN
 #define XSTR(s) STR (s)
@@ -166,7 +167,7 @@ NodeStateMessage::serialize (void* buf, size_t len) const
 					break;
 				}
 				case TypedValue::String:
-					ss << '"' << static_cast<std::string> (val) << '"';
+					ss << '"' << Json::escape (static_cast<std::string> (val)) << '"';
 					break;
 				default:
 					break;

libs/surfaces/websockets/resources.cc

@@ -16,7 +16,6 @@
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
-#include <iomanip>
 #include <iostream>
 #include <sstream>
 
@@ -27,6 +26,7 @@
 #include "pbd/file_utils.h"
 
 #include "resources.h"
+#include "json.h"
 
 static const char* const data_dir_env_var = "ARDOUR_WEBSURFACES_PATH";
 static const char* const data_dir_name = "web_surfaces";
@@ -46,23 +46,6 @@ ServerResources::ServerResources ()
 {
 }
 
-/* adapted from https://stackoverflow.com/questions/7724448/simple-json-string-escape-for-c
-   CC BY-SA 4.0 license */
-std::string
-ServerResources::escape_json (const std::string &s) {
-    std::ostringstream o;
-
-    for (std::string::const_iterator it = s.begin(); it != s.end(); ++it) {
-        if (*it == '"' || *it == '\\' || ('\x00' <= *it && *it <= '\x1f')) {
-            o << "\\u" << std::hex << std::setw (4) << std::setfill ('0') << static_cast<int>(*it);
-        } else {
-            o << *it;
-        }
-    }
-    
-    return o.str ();
-}
-
 const std::string&
 ServerResources::index_dir ()
 {
@@ -102,8 +85,8 @@ ServerResources::scan ()
 	SurfaceManifestVector builtin = read_manifests (builtin_dir_str);
 
 	ss << "[{"
-		<< "\"filesystemPath\":\"" << escape_json (builtin_dir_str) << "\""
-		<< ",\"path\":\"" << escape_json (builtin_dir_name) << "\""
+		<< "\"filesystemPath\":\"" << Json::escape (builtin_dir_str) << "\""
+		<< ",\"path\":\"" << Json::escape (builtin_dir_name) << "\""
 		<< ",\"surfaces\":"
 		<< "[";
 
@@ -118,8 +101,8 @@ ServerResources::scan ()
 	SurfaceManifestVector user = read_manifests (user_dir_str);
 
 	ss << "]},{" 
-		<< "\"filesystemPath\":\"" << escape_json(user_dir_str) << "\""
-		<< ",\"path\":\"" << escape_json(user_dir_name) << "\"" 
+		<< "\"filesystemPath\":\"" << Json::escape (user_dir_str) << "\""
+		<< ",\"path\":\"" << Json::escape (user_dir_name) << "\"" 
 		<< ",\"surfaces\":" 
 		<< "[";
 

libs/surfaces/websockets/resources.h

@@ -30,8 +30,6 @@ class ServerResources
 {
 public:
 	ServerResources ();
-	
-	static std::string escape_json (const std::string&);
 
 	const std::string& index_dir ();
 	const std::string& builtin_dir ();

libs/surfaces/websockets/wscript

@@ -29,6 +29,7 @@ def build(bld):
             dispatcher.cc
             manifest.cc
             resources.cc
+            json.cc
     '''
     obj.export_includes = ['.']
     obj.defines      = [ 'PACKAGE="ardour_websockets"' ]