* Fix Player getting stuck after teleport, etc. due to high number of achievements - patch by Trazom

http://www.trinitycore.org/forum/project.php?issueid=4329&page=4#note34721

--HG--
branch : trunk

src/game/WorldSocket.cpp

@@ -188,7 +188,8 @@ int WorldSocket::SendPacket (const WorldPacket& pct)
         sWorldLog.outLog ("\n");
     }
 
-    if (iSendPacket (pct) == -1)
+    // don't try to send the packet if there are packets on the queue
+    if (!m_PacketQueue.is_empty() || iSendPacket(pct) == -1)
     {
         WorldPacket* npct;
 
@@ -202,6 +203,12 @@ int WorldSocket::SendPacket (const WorldPacket& pct)
             sLog.outError ("WorldSocket::SendPacket: m_PacketQueue.enqueue_tail failed");
             return -1;
         }
+
+        // iSendPacket may fail if the packet is larger than the buffer (even in the buffer is empty)
+        // So we must try to flush so the packet may be sent partially
+        // don't cancel_wakeup_output here
+        if (iFlushPacketQueue())
+            return schedule_wakeup_output(Guard);
     }
 
     return 0;
@@ -321,10 +328,15 @@ int WorldSocket::handle_output (ACE_HANDLE)
     if (closing_)
         return -1;
 
-    const size_t send_len = m_OutBuffer->length ();
+    size_t send_len = m_OutBuffer->length();
 
     if (send_len == 0)
-        return cancel_wakeup_output (Guard);
+    {
+        if (!iFlushPacketQueue())
+            return cancel_wakeup_output(Guard);
+
+        send_len = m_OutBuffer->length ();
+    }
 
 #ifdef MSG_NOSIGNAL
     ssize_t n = peer ().send (m_OutBuffer->rd_ptr (), send_len, MSG_NOSIGNAL);
@@ -960,7 +972,7 @@ int WorldSocket::HandlePing (WorldPacket& recvPacket)
 int WorldSocket::iSendPacket (const WorldPacket& pct)
 {
     ServerPktHeader header(pct.size()+2, pct.GetOpcode());
-    if (m_OutBuffer->space () < pct.size () + header.getHeaderLength())
+    if (m_OutBuffer->space() < pct.size () + header.getHeaderLength())
     {
         errno = ENOBUFS;
         return -1;
@@ -979,16 +991,73 @@ int WorldSocket::iSendPacket (const WorldPacket& pct)
     return 0;
 }
 
-bool WorldSocket::iFlushPacketQueue ()
+/// Return 1 if some bytes written and packet completed
+/// Return 0 if no byte written, but still remaining data
+/// Return -1 if some bytes written and still remaining data
+int WorldSocket::iSendPartialPacket(WorldPacket& pct)
+{
+    size_t remainingLen = pct.size() - pct.rpos();
+
+    if (pct.rpos() == 0) // nothing sent yet => send header
+    {
+        ServerPktHeader header(pct.size()+2, pct.GetOpcode());
+
+        if (m_OutBuffer->space () < pct.size () + header.getHeaderLength())
+        {
+            // be sure to send big packet (otherwise, they would stay in the queue)
+            // So for packet larger than 1K, just check if there are some usefull space
+            if (pct.size() > 1024 && m_OutBuffer->space () < header.getHeaderLength() + 1024)
+            {
+                return 0; // nothing written, still remaining data => 0
+            }
+        }
+
+        m_Crypt.EncryptSend ( header.header, header.getHeaderLength());
+     
+        if (m_OutBuffer->copy ((char*) header.header, header.getHeaderLength()) == -1)
+            ACE_ASSERT (false);
+
+        if (remainingLen == 0)
+        {
+            return 1; // header written, nothing else => 1
+        }
+    }
+
+    if ((m_OutBuffer->space()) < remainingLen) {
+        size_t len = m_OutBuffer->space();
+
+        if (m_OutBuffer->copy ((char*) (pct.contents() + pct.rpos()), len) == -1)
+            ACE_ASSERT (false);
+
+        pct.read_skip(len);
+        return -1; // packet will be pushed back on the queue
+    }
+
+    if (m_OutBuffer->copy ((char*) (pct.contents() + pct.rpos()), remainingLen) == -1)
+         ACE_ASSERT (false);
+ 
+     return 1; // some byte written and packet completed 
+ }
+ 
+
+bool WorldSocket::iFlushPacketQueue()
 {
     WorldPacket *pct;
     bool haveone = false;
 
-    while (m_PacketQueue.dequeue_head (pct) == 0)
+    while (m_PacketQueue.dequeue_head(pct) == 0)
     {
-        if (iSendPacket (*pct) == -1)
+        int result = iSendPartialPacket(*pct);
+
+        if (result != 0) 
         {
-            if (m_PacketQueue.enqueue_head (pct) == -1)
+            // some bytes were written
+            haveone = true;
+        }
+
+        if (result <= 0)
+        {
+            if (m_PacketQueue.enqueue_head(pct) == -1)
             {
                 delete pct;
                 sLog.outError ("WorldSocket::iFlushPacketQueue m_PacketQueue->enqueue_head");
@@ -999,7 +1068,7 @@ bool WorldSocket::iFlushPacketQueue ()
         }
         else
         {
-            haveone = true;
+            // packet completed
             delete pct;
         }
     }

src/game/WorldSocket.h

@@ -175,6 +175,10 @@ class WorldSocket : protected WorldHandler
         /// Need to be called with m_OutBufferLock lock held
         int iSendPacket (const WorldPacket& pct);
 
+        /// Try to write WorldPacket to m_OutBuffer even partially, 
+        /// Need to be called with m_OutBufferLock lock held
+        int iSendPartialPacket(WorldPacket& pct);
+
         /// Flush m_PacketQueue if there are packets in it
         /// Need to be called with m_OutBufferLock lock held
         /// @return true if it wrote to the buffer ( AKA you need