libt2n: (gerd) add hello peek
[libt2n] / src / connection.cpp
index 0b445ef..d339f9f 100644 (file)
@@ -19,6 +19,9 @@
 
 #include <string>
 #include <sstream>
+#include <iostream>
+
+#include <netinet/in.h>
 
 #include "connection.hxx"
 
@@ -27,46 +30,71 @@ namespace libt2n
 
 connection::packet_size_indicator connection::bytes_available()
 {
-    // max packet size is unsigned int
-
     // no size information -> no packet
-    if (buffer.size() < sizeof(unsigned int))
-        return false;
+    if (buffer.size() < sizeof(packet_size_indicator))
+        return 0;
 
-    packet_size_indicator psize=*((packet_size_indicator*)(buffer.data()));
+    packet_size_indicator psize=ntohl(*((packet_size_indicator*)(buffer.data())));
 
     // enough data for one packet in buffer?
-    if (buffer.size() < sizeof(unsigned int)+psize)
-        return false;
+    if (buffer.size() < sizeof(packet_size_indicator)+psize)
+        return 0;
 
     // ok, full packet there
-    return true;
+    return psize;
 }
 
+/** @brief read a complete data packet from the buffer. The packet is removed from the
+            connection buffer.
+    @param[out] data the data package
+    @retval true if packet found
+*/
 bool connection::get_packet(std::string& data)
 {
     packet_size_indicator psize;
 
     if ((psize=bytes_available()))
     {
-        data.assign(buffer,sizeof(unsigned int),psize);
-        buffer.erase(0,sizeof(unsigned int)+psize);
+        data.assign(buffer,sizeof(packet_size_indicator),psize);
+        buffer.erase(0,sizeof(packet_size_indicator)+psize);
         return true;
     }
     else
         return false;
 }
 
+/** @brief get (maybe incomplete) data of the next packet from the buffer. Does not remove the data
+            from the connection buffer.
+    @param[out] data the data package
+    @retval full size of the packet when it will be complete
+*/
+unsigned int connection::peek_packet(std::string& data)
+{
+    // no size information -> no packet
+    if (buffer.size() < sizeof(packet_size_indicator))
+        return 0;
+
+    packet_size_indicator psize=ntohl(*((packet_size_indicator*)(buffer.data())));
+
+    // not the full data available?
+    packet_size_indicator currsize=psize;
+    if (buffer.size() < currsize+sizeof(packet_size_indicator))
+        currsize=buffer.size()-sizeof(packet_size_indicator);
+
+    data.assign(buffer,sizeof(packet_size_indicator),currsize);
+
+    return psize;
+}
+
+/// send a blob to the peer
 void connection::write(const std::string& data)
 {
     // prepend packet size to data
-    packet_size_indicator psize=data.size();
+    packet_size_indicator psize=htonl(data.size());
     std::string send_data(data);
-    send_data.insert(0,(char*)psize,sizeof(packet_size_indicator));
+    send_data.insert(0,(char*)&psize,sizeof(packet_size_indicator));
 
     real_write(send_data);
 }
 
-
-
 }