C++-ified pb2json.

pb2json.cpp

@@ -1,23 +1,22 @@
 #include "pb2json.h"
 
+#include <jansson.h>
+
+#include <google/protobuf/descriptor.h>
+#include <google/protobuf/message.h>
+
+#include <string>
+
+using namespace google::protobuf;
 using std::string;
-char * pb2json(const Message &msg)
-{
-	json_t *root = parse_msg(&msg);
-	char *json = json_dumps(root,0);
-	json_decref(root);
-	return json; // should be freed by caller
-}
-char * pb2json( Message *msg,const char *buf ,int len)
+
+
+namespace /*unnamed*/
 {
-	string s (buf,len);
-	msg->ParseFromString(s);
-	json_t *root = parse_msg(msg);
-	char *json = json_dumps(root,0);
-	json_decref(root);
-	return json; // should be freed by caller
-}
-static json_t *parse_repeated_field(const Message *msg,const Reflection * ref,const FieldDescriptor *field)
+
+json_t *parse_msg(const Message *msg);
+
+json_t *parse_repeated_field(const Message *msg,const Reflection * ref,const FieldDescriptor *field)
 {
 	size_t count = ref->FieldSize(*msg,field);
 	json_t *arr = json_array();	
@@ -99,7 +98,8 @@ static json_t *parse_repeated_field(const Message *msg,const Reflection * ref,co
 	}
 	return arr;
 }
-static json_t *parse_msg(const Message *msg)
+
+json_t *parse_msg(const Message *msg)
 {
 	const Descriptor *d = msg->GetDescriptor();
 	if(!d)return NULL;
@@ -181,5 +181,16 @@ static json_t *parse_msg(const Message *msg)
 
 	}
 	return root;
+}
+
+} // namespace /*unnamed*/
 
+std::string pb2json(const google::protobuf::Message& msg)
+{
+  json_t *root = parse_msg(&msg);
+  char *buffer = json_dumps(root,0);
+  json_decref(root);
+  string json(buffer);
+  free(buffer);
+  return json;
 }

pb2json.h

@@ -1,9 +1,25 @@
-#include <jansson.h>
+#ifndef PB2JSON_H
+#define PB2JSON_H
+
 #include <string>
-#include <google/protobuf/descriptor.h>
-#include <google/protobuf/message.h>
-using namespace google::protobuf;
-char *pb2json(const Message &msg);
-char *pb2json(Message *msg,const char *buf,int len);
-static json_t *parse_msg(const Message *msg);
-static json_t *parse_repeated_field(const Message *msg,const Reflection * ref,const FieldDescriptor *field);
+
+// Forward declaration
+namespace google
+{
+  namespace protobuf
+  {
+    class Message;
+  } // namespace protobuf
+} // namespace google
+
+std::string pb2json(const google::protobuf::Message& msg);
+
+template <typename PbMessageType>
+std::string pb2json(const std::string& str)
+{
+  PbMessageType msg;
+  msg.ParseFromString(str);
+  return pb2json(msg);
+}
+
+#endif // PB2JSON_H

test/test_json.cpp

@@ -1,10 +1,12 @@
 #include <fstream>
 #include <iostream>
+
 #include "person.pb.h"
-//#include "../pb2json.h"
+
 #include <pb2json.h>
 
 using namespace std;
+using namespace google::protobuf;
 
 int main(int argc,char *argv[])
 {
@@ -13,20 +15,18 @@ int main(int argc,char *argv[])
 	fin.seekg(0,ios_base::end);
 	size_t len = fin.tellg();
 	fin.seekg(0,ios_base::beg);
-	char *buf = new char [len];
 
-	fin.read(buf,len);
-	Message *p = new Person();
-	char *json = pb2json(p,buf,len);
+        string buf(len, 0);
+	fin.read(&buf[0],len);
+
+	string json = pb2json<Person>(buf);
 	cout<<json<<endl;
-	free(json);
-	delete p;
 
 	// Test 2: convert PB to JSON directly
-	Person p2;
-	char *json2 = pb2json(p2);
+	Person p;
+        p.ParseFromString(buf);
+	string json2 = pb2json(p);
 	cout<<json2<<endl;
-	free(json2);
 
 	return 0;
 }

test/test_person.cpp

@@ -1,5 +1,6 @@
 #include <iostream>
 #include <fstream>
+
 #include "person.pb.h"
 
 using namespace std;