add MQTT stuff

PString/PString.cpp

@@ -0,0 +1,60 @@
+/*
+  PString.cpp - Lightweight printable string class
+  Copyright (c) 2009-2012 Mikal Hart.  All right reserved.
+
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+
+  This library 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+#include "PString.h"
+
+void PString::begin()
+{
+  _cur = _buf;
+  if (_size > 0)
+    _buf[0] = '\0';
+}
+
+#if defined(ARDUINO) && ARDUINO >= 100
+size_t PString::write(uint8_t b)
+#else
+void PString::write(uint8_t b)
+#endif
+{
+  if (_cur + 1 < _buf + _size)
+  {
+    *_cur++ = (char)b;
+    *_cur = '\0';
+#if defined(ARDUINO) && ARDUINO >= 100
+		return 1;
+#endif
+	}
+
+#if defined(ARDUINO) && ARDUINO >= 100
+	return 0;
+#endif
+}
+
+int PString::format(char *str, ...) 
+{ 
+  va_list argptr;  
+  va_start(argptr, str); 
+  int ret = vsnprintf(_cur, _size - (_cur - _buf), str, argptr);
+  if (_size)
+     while (*_cur) 
+        ++_cur;
+  return ret;
+}
+
+