Fixed several buffer segfaults when multiple viewers are connected.

lib/dtsc.cpp

@@ -126,6 +126,7 @@ bool DTSC::Stream::parsePacket(Socket::Buffer & buffer){
       std::string wholepacket = buffer.remove(len + 8);
       metadata = JSON::fromDTMI((unsigned char*)wholepacket.c_str() + 8, len, i);
       metadata.removeMember("moreheader");
+      metadata.netPrepare();
       if ( !buffer.available(8)){
         return false;
       }
@@ -332,7 +333,7 @@ void DTSC::Stream::updateHeaders(){
       metadata.removeMember("frags");
       metadata.removeMember("lastms");
       metadata.removeMember("missed_frags");
-      metadata.toPacked();
+      metadata.netPrepare();
       return;
     }
     metadata["keytime"].shrink(keyframes.size() - 2);
@@ -370,7 +371,7 @@ void DTSC::Stream::updateHeaders(){
     metadata["lastms"] = buffers[keyframes[0].b]["time"].asInt();
     metadata["buffer_window"] = (long long int)buffertime;
     metadata["live"] = true;
-    metadata.toPacked();
+    metadata.netPrepare();
     updateRingHeaders();
   }
 }
@@ -592,7 +593,7 @@ void DTSC::File::readHeader(int pos){
     }
   }
   metadata["vod"] = true;
-  metadata.toPacked();
+  metadata.netPrepare();
 }
 
 /// Reads the packet available at the current file position.

lib/json.cpp

@@ -464,22 +464,16 @@ std::string JSON::Value::toPacked(){
   }
   return r;
 }
-;
 //toPacked
 
-/// Packs any object-type JSON::Value to a std::string for transfer over the network, including proper DTMI header.
+/// Pre-packs any object-type JSON::Value to a std::string for transfer over the network, including proper DTMI header.
-/// Non-object-types will print an error to stderr and return an empty string.
+/// Non-object-types will print an error to stderr.
-/// This function returns a reference to an internal buffer where the prepared data is kept.
+/// The internal buffer is guaranteed to be up-to-date after this function is called.
-/// The internal buffer is *not* made stale if any changes occur inside the object - subsequent calls to toPacked() will clear the buffer.
+void JSON::Value::netPrepare(){
-std::string & JSON::Value::toNetPacked(){
-  static std::string emptystring;
-  //check if this is legal
   if (myType != OBJECT){
     fprintf(stderr, "Error: Only objects may be NetPacked!\n");
-    return emptystring;
+    return;
   }
-  //if sneaky storage doesn't contain correct data, re-calculate it
-  if (strVal.size() == 0 || strVal[0] != 'D' || strVal[1] != 'T'){
   std::string packed = toPacked();
   strVal.resize(packed.size() + 8);
   //insert proper header for this type of data
@@ -494,6 +488,23 @@ std::string & JSON::Value::toNetPacked(){
   //copy the rest of the string
   memcpy((void*)(strVal.c_str() + 8), packed.c_str(), packed.size());
 }
+
+/// Packs any object-type JSON::Value to a std::string for transfer over the network, including proper DTMI header.
+/// Non-object-types will print an error to stderr and return an empty string.
+/// This function returns a reference to an internal buffer where the prepared data is kept.
+/// The internal buffer is *not* made stale if any changes occur inside the object - subsequent calls to toPacked() will clear the buffer,
+/// calls to netPrepare will guarantee it is up-to-date.
+std::string & JSON::Value::toNetPacked(){
+  static std::string emptystring;
+  //check if this is legal
+  if (myType != OBJECT){
+    fprintf(stderr, "Error: Only objects may be NetPacked!\n");
+    return emptystring;
+  }
+  //if sneaky storage doesn't contain correct data, re-calculate it
+  if (strVal.size() == 0 || strVal[0] != 'D' || strVal[1] != 'T'){
+    netPrepare();
+  }
   return strVal;
 }
 

lib/json.h

@@ -70,6 +70,7 @@ namespace JSON {
       Value & operator[](unsigned int i);
       //handy functions and others
       std::string toPacked();
+      void netPrepare();
       std::string & toNetPacked();
       std::string toString();
       std::string toPrettyString(int indentation = 0);