Move pMiningKey init out of StartRPCThreads

This commit decouples the pMiningKey initialization and shutdown from the RPC
threads.

`getwork` and `getblocktemplate` rely on pMiningKey, and can also be ran
from the debug window in the UI even when the RPC server is not running.

Solves issue #2706.

src/bitcoinrpc.cpp

@@ -30,10 +30,6 @@ using namespace boost;
 using namespace boost::asio;
 using namespace json_spirit;
 
-// Key used by getwork/getblocktemplate miners.
-// Allocated in StartRPCThreads, free'd in StopRPCThreads
-CReserveKey* pMiningKey = NULL;
-
 static std::string strRPCUserColonPass;
 
 // These are created by StartRPCThreads, destroyed in StopRPCThreads
@@ -726,9 +722,6 @@ static void RPCAcceptHandler(boost::shared_ptr< basic_socket_acceptor<Protocol,
 
 void StartRPCThreads()
 {
-    // getwork/getblocktemplate mining rewards paid here:
-    pMiningKey = new CReserveKey(pwalletMain);
-
     strRPCUserColonPass = mapArgs["-rpcuser"] + ":" + mapArgs["-rpcpassword"];
     if ((mapArgs["-rpcpassword"] == "") ||
         (mapArgs["-rpcuser"] == mapArgs["-rpcpassword"]))
@@ -848,8 +841,6 @@ void StartRPCThreads()
 
 void StopRPCThreads()
 {
-    delete pMiningKey; pMiningKey = NULL;
-
     if (rpc_io_service == NULL) return;
 
     rpc_io_service->stop();

src/bitcoinrpc.h

@@ -123,7 +123,9 @@ public:
 };
 
 extern const CRPCTable tableRPC;
-extern CReserveKey* pMiningKey;
+
+extern void InitRPCMining();
+extern void ShutdownRPCMining();
 
 extern int64 nWalletUnlockTime;
 extern int64 AmountFromValue(const json_spirit::Value& value);

src/init.cpp

@@ -96,6 +96,7 @@ void Shutdown()
     RenameThread("bitcoin-shutoff");
     nTransactionsUpdated++;
     StopRPCThreads();
+    ShutdownRPCMining();
     bitdb.Flush(false);
     StopNode();
     {
@@ -1081,6 +1082,8 @@ bool AppInit2(boost::thread_group& threadGroup)
 
     StartNode(threadGroup);
 
+    // InitRPCMining is needed here so getwork/getblocktemplate in the GUI debug console works properly.
+    InitRPCMining();
     if (fServer)
         StartRPCThreads();
 

src/rpcmining.cpp

@@ -11,6 +11,21 @@
 using namespace json_spirit;
 using namespace std;
 
+// Key used by getwork/getblocktemplate miners.
+// Allocated in InitRPCMining, free'd in ShutdownRPCMining
+static CReserveKey* pMiningKey = NULL;
+
+void InitRPCMining()
+{
+    // getwork/getblocktemplate mining rewards paid here:
+    pMiningKey = new CReserveKey(pwalletMain);
+}
+
+void ShutdownRPCMining()
+{
+    delete pMiningKey; pMiningKey = NULL;
+}
+
 Value getgenerate(const Array& params, bool fHelp)
 {
     if (fHelp || params.size() != 0)