serialize maps

include/sp/common/DataBuffer.h

@@ -13,6 +13,7 @@
 #include <string>
 #include <sp/common/VarInt.h>
 #include <vector>
+#include <map>
 
 namespace sp {
 
@@ -88,6 +89,19 @@ class DataBuffer {
 		return *this;
 	}
 
+	/**
+	 * \brief Append a map to the buffer by first writing the size
+	 * \param data The map to append
+	 */
+	template <typename K, typename V>
+	DataBuffer& operator<<(const std::map<K, V>& data) {
+		*this << VarInt{data.size()};
+		for (const auto& element : data) {
+			*this << element.first << element.second;
+		}
+		return *this;
+	}
+
 	/**
 	 * \brief Append an array to the buffer by first writing the size
 	 * \param data The buffer to append
@@ -140,6 +154,23 @@ class DataBuffer {
 		return *this;
 	}
 
+	/**
+	 * \brief Read a map (size + data) from the buffer
+	 * \pre The map is assumed to be empty
+	 */
+	template <typename K, typename V>
+	DataBuffer& operator>>(std::map<K, V>& data) {
+		VarInt mapSize;
+		*this >> mapSize;
+		for (std::size_t i = 0; i < mapSize.GetValue(); i++) {
+			K newKey;
+			V newValue;
+			*this >> newKey >> newValue;
+			data.insert({newKey, newValue});
+		}
+		return *this;
+	}
+
 	/**
 	 * \brief Read an array from the buffer
 	 */