intercept callback support

include/enet/enet.h

@@ -319,6 +319,9 @@ typedef struct _ENetCompressor
 
 /** Callback that computes the checksum of the data held in buffers[0:bufferCount-1] */
 typedef enet_uint32 (ENET_CALLBACK * ENetChecksumCallback) (const ENetBuffer * buffers, size_t bufferCount);
+
+/** Callback for intercepting received raw UDP packets. Should return 1 to intercept, 0 to ignore, or -1 to propagate an error. */
+typedef int (ENET_CALLBACK * ENetInterceptCallback) (ENetHost * host, ENetEvent * event);
  
 /** An ENet host for communicating with peers.
   *
@@ -368,6 +371,7 @@ typedef struct _ENetHost
    enet_uint32          totalSentPackets;            /**< total UDP packets sent, user should reset to 0 as needed to prevent overflow */
    enet_uint32          totalReceivedData;           /**< total data received, user should reset to 0 as needed to prevent overflow */
    enet_uint32          totalReceivedPackets;        /**< total UDP packets received, user should reset to 0 as needed to prevent overflow */
+   ENetInterceptCallback intercept;                  /**< callback the user can set to intercept received raw UDP packets */
 } ENetHost;
 
 /**

protocol.c

@@ -1194,7 +1194,25 @@ enet_protocol_receive_incoming_commands (ENetHost * host, ENetEvent * event)
       
        host -> totalReceivedData += receivedLength;
        host -> totalReceivedPackets ++;
- 
+
+       if (host -> intercept != NULL)
+       {
+          switch (host -> intercept (host, event))
+          {
+          case 1:
+             if (event != NULL && event -> type != ENET_EVENT_TYPE_NONE)
+               return 1;
+
+             continue;
+          
+          case -1:
+             return -1;
+        
+          default:
+             break;
+          }
+       }
+        
        switch (enet_protocol_handle_incoming_commands (host, event))
        {
        case 1: