fixed: get full json objects from the tcp stream, and parse them

src/kodiclient.cpp

@@ -21,6 +21,7 @@
 
 #include <cstdio>
 #include <unistd.h>
+#include <cstdint>
 
 #include <iostream>
 #include <boost/asio.hpp>
@@ -61,22 +62,63 @@ void CKodiClient::Process()
       printf("Connected to Kodi\n");
 
       //Keep reading data from Kodi, when the tcp socket is closed an exception is thrown.
+      uint32_t    bracketlevel = 0;
+      bool        instring = false;
+      bool        escaped  = false;
+      std::string jsonstr;
       for(;;)
       {
         boost::asio::streambuf receive_buffer;
-        size_t readbytes = boost::asio::read(socket, receive_buffer, boost::asio::transfer_at_least(1));
+        size_t bytesread = boost::asio::read(socket, receive_buffer, boost::asio::transfer_at_least(1));
+
         const char* data = boost::asio::buffer_cast<const char*>(receive_buffer.data());
 
-        //TODO: because of TCP, one read does not exactly equal one JSON object.
-        json jsondata = json::parse(data);
-
-        //If Kodi signals a Player.OnPlay notification, the amplifier should be turned on.
-        if (jsondata.contains("method"))
+        //Parse the JSON data into separate JSON objects by finding the text from
+        //the starting { to ending }, while ignoring curly brackets in strings.
+        for (uint32_t i = 0; i < (uint32_t)bytesread; i++)
         {
-          if (jsondata["method"] == "Player.OnPlay")
+          jsonstr.push_back(data[i]);
+
+          if (!instring)
           {
-            printf("Player started\n");
-            m_ampswitch->SignalPlayStart();
+            if (data[i] == '"')
+            {
+              instring = true;
+            }
+            else if (data[i] == '{')
+            {
+              bracketlevel++;
+            }
+            else if (data[i] == '}')
+            {
+              if (bracketlevel > 0)
+              {
+                bracketlevel--;
+                if (bracketlevel == 0)
+                {
+                  Parse(jsonstr);
+                  jsonstr.clear();
+                }
+              }
+              else
+              {
+                jsonstr.clear(); //Shouldn't happen.
+              }
+            }
+          }
+          else
+          {
+            if (!escaped)
+            {
+              if (data[i] == '\\')
+                escaped = true;
+              else if (data[i] == '"')
+                instring = false;
+            }
+            else
+            {
+              escaped = false;
+            }
           }
         }
       }
@@ -89,3 +131,18 @@ void CKodiClient::Process()
     }
   }
 }
+
+void CKodiClient::Parse(const std::string& jsonstr)
+{
+  json jsondata = json::parse(jsonstr);
+
+  //If Kodi signals a Player.OnPlay notification, the amplifier should be turned on.
+  if (jsondata.contains("method"))
+  {
+    if (jsondata["method"] == "Player.OnPlay")
+    {
+      printf("Player started\n");
+      m_ampswitch->SignalPlayStart();
+    }
+  }
+}

src/kodiclient.h

@@ -20,6 +20,7 @@
 #define KODICLIENT_H
 
 #include <thread>
+#include <string>
 
 class CAmpSwitch;
 
@@ -31,6 +32,7 @@ class CKodiClient
   private:
     static void SProcess(CKodiClient* kodiclient);
     void        Process();
+    void        Parse(const std::string& jsonstr);
 
     std::thread m_thread;
     CAmpSwitch* m_ampswitch;