fixup! implementing encoder interface

Author: andreagilardoni

src/cbor/CborEncoder.cpp

@@ -9,10 +9,9 @@
 */
 #include "CborEncoder.h"
 
-static CBORMessageEncoderClass* singleton = nullptr;
-CBORMessageEncoderClass& CBORMessageEncoder = CBORMessageEncoderClass::getInstance();
+// static CBORMessageEncoderSingleton* singleton = nullptr;
 
-Encoder::Status CBORMessageEncoderClass::encode(Message* message, uint8_t * data, size_t& len) { // TODO do we need to propagate the maximum length?
+Encoder::Status CBORMessageEncoderSingleton::encode(Message* message, uint8_t * data, size_t& len) { // TODO do we need to propagate the maximum length?
   // prepare cbor structure
   CborEncoder encoder;
 
@@ -35,17 +34,16 @@ Encoder::Status CBORMessageEncoderClass::encode(Message* message, uint8_t * data
   return Encoder::Status::Complete;
 }
 
-CBORMessageEncoderClass& CBORMessageEncoderClass::getInstance() {
-  if(singleton == nullptr) {
-    singleton = new CBORMessageEncoderClass();
-  }
-  return *singleton;
+CBORMessageEncoderSingleton& CBORMessageEncoderSingleton::getInstance() {
+  static CBORMessageEncoderSingleton singleton;
+
+  return singleton;
 }
 
 CBORMessageEncoderInterface::CBORMessageEncoderInterface(const CBORTag tag, const MessageId id)
 : tag(tag), id(id) {
   // call singleton/global variable and insert this encoder
-  CBORMessageEncoderClass::getInstance().append(id, this);
+  CBORMessageEncoderSingleton::getInstance().append(id, this);
 }
 
 Encoder::Status CBORMessageEncoderInterface::_encode(CborEncoder* encoder, Message *msg) {

src/cbor/CborEncoder.h

@@ -15,14 +15,13 @@
 #include "../interfaces/message.h"
 #include "./tinycbor/cbor-lib.h"
 
-class CBORMessageEncoderClass;
+class CBORMessageEncoderSingleton;
 
 
 // TODO find a better name
 // TODO maybe a template<CBORTag tag, MessageId id> ?
 // TODO maybe template<resultStruct> that is also the parameter of encode
 // TODO in order to make this more extensible we should not pass Message* as a parameter, templated function may be better (or void*)
-// providing both id and tag gives the ability to convert and avoid using a conversion function
 class CBORMessageEncoderInterface {
 public:
   CBORMessageEncoderInterface(const CBORTag tag, const MessageId id);
@@ -35,25 +34,31 @@ class CBORMessageEncoderInterface {
   const CBORTag tag;
   const MessageId id;
 
-  friend CBORMessageEncoderClass;
+  friend CBORMessageEncoderSingleton;
 
   // wrapper for encode function that for the time being only writes the tag in the buffer
   Encoder::Status _encode(CborEncoder* encoder, Message *msg);
 };
 
-// TODO make a private constructor?
-class CBORMessageEncoderClass: public Encoder {
+class CBORMessageEncoderSingleton: public Encoder {
 public:
-CBORMessageEncoderClass() {}
-  static CBORMessageEncoderClass& getInstance();
+  static CBORMessageEncoderSingleton& getInstance();
 
   void append(CBORTag id, CBORMessageEncoderInterface* encoder) {
     encoders[id] = encoder;
   }
 
   Encoder::Status encode(Message* message, uint8_t * data, size_t& len);
 private:
+  CBORMessageEncoderSingleton() {}
+
+  static CBORMessageEncoderSingleton singleton;
   std::map<MessageId, CBORMessageEncoderInterface*> encoders;
 };
 
-extern CBORMessageEncoderClass& CBORMessageEncoder;
+class CBORMessageEncoder: public Encoder {
+public:
+  inline Encoder::Status encode(Message* msg, uint8_t* buf, size_t &len) {
+    return CBORMessageEncoderSingleton::getInstance().encode(msg, buf, len);
+  }
+};