Added a return value to visitors

src/ArduinoJson/MsgPack/MsgPackSerializer.hpp

@@ -7,6 +7,7 @@
 #include <ArduinoJson/MsgPack/endianess.hpp>
 #include <ArduinoJson/Polyfills/assert.hpp>
 #include <ArduinoJson/Polyfills/type_traits.hpp>
+#include <ArduinoJson/Serialization/CountingDecorator.hpp>
 #include <ArduinoJson/Serialization/measure.hpp>
 #include <ArduinoJson/Serialization/serialize.hpp>
 #include <ArduinoJson/Variant/VariantData.hpp>
@@ -14,19 +15,20 @@
 namespace ARDUINOJSON_NAMESPACE {
 
 template <typename TWriter>
-class MsgPackSerializer {
+class MsgPackSerializer : public Visitor<size_t> {
  public:
-  MsgPackSerializer(TWriter writer) : _writer(writer), _bytesWritten(0) {}
+  MsgPackSerializer(TWriter writer) : _writer(writer) {}
 
   template <typename T>
-  typename enable_if<sizeof(T) == 4>::type visitFloat(T value32) {
+  typename enable_if<sizeof(T) == 4, size_t>::type visitFloat(T value32) {
     writeByte(0xCA);
     writeInteger(value32);
+    return bytesWritten();
   }
 
   template <typename T>
   ARDUINOJSON_NO_SANITIZE("float-cast-overflow")
-  typename enable_if<sizeof(T) == 8>::type visitFloat(T value64) {
+  typename enable_if<sizeof(T) == 8, size_t>::type visitFloat(T value64) {
     float value32 = float(value64);
     if (value32 == value64) {
       writeByte(0xCA);
@@ -35,9 +37,10 @@ class MsgPackSerializer {
       writeByte(0xCB);
       writeInteger(value64);
     }
+    return bytesWritten();
   }
 
-  void visitArray(const CollectionData& array) {
+  size_t visitArray(const CollectionData& array) {
     size_t n = array.size();
     if (n < 0x10) {
       writeByte(uint8_t(0x90 + array.size()));
@@ -51,9 +54,10 @@ class MsgPackSerializer {
     for (VariantSlot* slot = array.head(); slot; slot = slot->next()) {
       slot->data()->accept(*this);
     }
+    return bytesWritten();
   }
 
-  void visitObject(const CollectionData& object) {
+  size_t visitObject(const CollectionData& object) {
     size_t n = object.size();
     if (n < 0x10) {
       writeByte(uint8_t(0x80 + n));
@@ -68,9 +72,10 @@ class MsgPackSerializer {
       visitString(slot->key());
       slot->data()->accept(*this);
     }
+    return bytesWritten();
   }
 
-  void visitString(const char* value) {
+  size_t visitString(const char* value) {
     ARDUINOJSON_ASSERT(value != NULL);
 
     size_t n = strlen(value);
@@ -88,13 +93,15 @@ class MsgPackSerializer {
       writeInteger(uint32_t(n));
     }
     writeBytes(reinterpret_cast<const uint8_t*>(value), n);
+    return bytesWritten();
   }
 
-  void visitRawJson(const char* data, size_t size) {
+  size_t visitRawJson(const char* data, size_t size) {
     writeBytes(reinterpret_cast<const uint8_t*>(data), size);
+    return bytesWritten();
   }
 
-  void visitNegativeInteger(UInt value) {
+  size_t visitNegativeInteger(UInt value) {
     UInt negated = UInt(~value + 1);
     if (value <= 0x20) {
       writeInteger(int8_t(negated));
@@ -114,9 +121,10 @@ class MsgPackSerializer {
       writeInteger(int64_t(negated));
     }
 #endif
+    return bytesWritten();
   }
 
-  void visitPositiveInteger(UInt value) {
+  size_t visitPositiveInteger(UInt value) {
     if (value <= 0x7F) {
       writeInteger(uint8_t(value));
     } else if (value <= 0xFF) {
@@ -141,27 +149,30 @@ class MsgPackSerializer {
       writeInteger(uint64_t(value));
     }
 #endif
+    return bytesWritten();
   }
 
-  void visitBoolean(bool value) {
+  size_t visitBoolean(bool value) {
     writeByte(value ? 0xC3 : 0xC2);
+    return bytesWritten();
   }
 
-  void visitNull() {
+  size_t visitNull() {
     writeByte(0xC0);
-  }
-
-  size_t bytesWritten() const {
-    return _bytesWritten;
+    return bytesWritten();
   }
 
  private:
+  size_t bytesWritten() const {
+    return _writer.count();
+  }
+
   void writeByte(uint8_t c) {
-    _bytesWritten += _writer.write(c);
+    _writer.write(c);
   }
 
   void writeBytes(const uint8_t* p, size_t n) {
-    _bytesWritten += _writer.write(p, n);
+    _writer.write(p, n);
   }
 
   template <typename T>
@@ -170,8 +181,7 @@ class MsgPackSerializer {
     writeBytes(reinterpret_cast<uint8_t*>(&value), sizeof(value));
   }
 
-  TWriter _writer;
-  size_t _bytesWritten;
+  CountingDecorator<TWriter> _writer;
 };
 
 template <typename TSource, typename TDestination>