Make some global variables less-global (static)

Explicitly make these global variables less-global to reduce the maximum
scope of this global state.

In my experience global variables tend to be a major source of bugs. As
such the less accessible they are the less likely they are to be the
source of a bug.

Signed-off-by: Giel van Schijndel <me@mortis.eu>

src/main.cpp

@@ -22,14 +22,14 @@ set<CWallet*> setpwalletRegistered;
 
 CCriticalSection cs_main;
 
-map<uint256, CTransaction> mapTransactions;
+static map<uint256, CTransaction> mapTransactions;
 CCriticalSection cs_mapTransactions;
 unsigned int nTransactionsUpdated = 0;
 map<COutPoint, CInPoint> mapNextTx;
 
 map<uint256, CBlockIndex*> mapBlockIndex;
 uint256 hashGenesisBlock("0x000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f");
-CBigNum bnProofOfWorkLimit(~uint256(0) >> 32);
+static CBigNum bnProofOfWorkLimit(~uint256(0) >> 32);
 const int nTotalBlocksEstimate = 134444; // Conservative estimate of total nr of blocks on main chain
 const int nInitialBlockThreshold = 120; // Regard blocks up until N-threshold as "initial download"
 CBlockIndex* pindexGenesisBlock = NULL;

src/main.h

@@ -54,7 +54,6 @@ static const int fHaveUPnP = false;
 extern CCriticalSection cs_main;
 extern std::map<uint256, CBlockIndex*> mapBlockIndex;
 extern uint256 hashGenesisBlock;
-extern CBigNum bnProofOfWorkLimit;
 extern CBlockIndex* pindexGenesisBlock;
 extern int nBestHeight;
 extern CBigNum bnBestChainWork;
@@ -1558,16 +1557,4 @@ public:
     bool ProcessAlert();
 };
 
-
-
-
-
-
-
-
-
-
-
-extern std::map<uint256, CTransaction> mapTransactions;
-
 #endif

src/net.cpp

@@ -50,10 +50,10 @@ bool fClient = false;
 bool fAllowDNS = false;
 uint64 nLocalServices = (fClient ? 0 : NODE_NETWORK);
 CAddress addrLocalHost("0.0.0.0", 0, false, nLocalServices);
-CNode* pnodeLocalHost = NULL;
+static CNode* pnodeLocalHost = NULL;
 uint64 nLocalHostNonce = 0;
 array<int, 10> vnThreadsRunning;
-SOCKET hListenSocket = INVALID_SOCKET;
+static SOCKET hListenSocket = INVALID_SOCKET;
 
 vector<CNode*> vNodes;
 CCriticalSection cs_vNodes;

src/net.h

@@ -476,10 +476,8 @@ extern bool fClient;
 extern bool fAllowDNS;
 extern uint64 nLocalServices;
 extern CAddress addrLocalHost;
-extern CNode* pnodeLocalHost;
 extern uint64 nLocalHostNonce;
 extern boost::array<int, 10> vnThreadsRunning;
-extern SOCKET hListenSocket;
 
 extern std::vector<CNode*> vNodes;
 extern CCriticalSection cs_vNodes;