Fix potential deadlock

Conflict:
* cs_main in ProcessMessages() (before calling ProcessMessages)
* cs_vSend in CNode::BeginMessage
versus:
* cs_vSend in ThreadMessageHandler2 (before calling SendMessages)
* cs_main in SendMessages

Even though cs_vSend is a try_lock, if it succeeds simultaneously with
the locking of cs_main in ProcessMessages(), it could cause a deadlock.

diff --git a/src/main.cpp b/src/main.cpp
index 76e0783..e6f9421 100644 (file)
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -2618,7 +2618,7 @@ bool ProcessMessages(CNode* pfrom)
 
 bool SendMessages(CNode* pto, bool fSendTrickle)
 {
-    CRITICAL_BLOCK(cs_main)
+    TRY_CRITICAL_BLOCK(cs_main)
     {
         // Don't send anything until we get their version message
         if (pto->nVersion == 0)