Reworked fixed change address handling to parse addresses on init and store in a vector

within the wallet code.

src/init.cpp

@@ -2,6 +2,7 @@
 // Copyright (c) 2009-2014 The Bitcoin developers
 // Copyright (c) 2011-2013 The Litecoin developers
 // Copyright (c)      2014 The Inutoshi developers
+// Copyright (c)      2014 The Dogecoin developers
 // Distributed under the MIT/X11 software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
@@ -12,7 +13,9 @@
 #include "init.h"
 
 #include "addrman.h"
+#include "base58.h"
 #include "checkpoints.h"
+#include "key.h"
 #include "main.h"
 #include "miner.h"
 #include "net.h"
@@ -207,7 +210,6 @@ std::string HelpMessage(HelpMessageMode hmm)
     strUsage += "  -maxconnections=<n>    " + _("Maintain at most <n> connections to peers (default: 125)") + "\n";
     strUsage += "  -addnode=<ip>          " + _("Add a node to connect to and attempt to keep the connection open") + "\n";
     strUsage += "  -connect=<ip>          " + _("Connect only to the specified node(s)") + "\n";
-    strUsage += "  -change=<address>      " + _("Send change only to the specified address(es)") + "\n" +
     strUsage += "  -seednode=<ip>         " + _("Connect to a node to retrieve peer addresses, and disconnect") + "\n";
     strUsage += "  -externalip=<ip>       " + _("Specify your own public address") + "\n";
     strUsage += "  -onlynet=<net>         " + _("Only connect to nodes in network <net> (IPv4, IPv6 or Tor)") + "\n";
@@ -220,7 +222,7 @@ std::string HelpMessage(HelpMessageMode hmm)
     strUsage += "  -bantime=<n>           " + _("Number of seconds to keep misbehaving peers from reconnecting (default: 86400)") + "\n";
     strUsage += "  -maxreceivebuffer=<n>  " + _("Maximum per-connection receive buffer, <n>*1000 bytes (default: 5000)") + "\n";
     strUsage += "  -maxsendbuffer=<n>     " + _("Maximum per-connection send buffer, <n>*1000 bytes (default: 1000)") + "\n";
-	strUsage += "  -bloomfilters          " + _("Allow peers to set bloom filters (default: 1)") + "\n" +
+        strUsage += "  -bloomfilters          " + _("Allow peers to set bloom filters (default: 1)") + "\n" +
 #ifdef USE_UPNP
 #if USE_UPNP
     strUsage += "  -upnp                  " + _("Use UPnP to map the listening port (default: 1 when listening)") + "\n";
@@ -278,6 +280,7 @@ std::string HelpMessage(HelpMessageMode hmm)
     strUsage += "  -upgradewallet         " + _("Upgrade wallet to latest format") + "\n";
     strUsage += "  -wallet=<file>         " + _("Specify wallet file (within data directory)") + "\n";
     strUsage += "  -walletnotify=<cmd>    " + _("Execute command when a wallet transaction changes (%s in cmd is replaced by TxID)") + "\n";
+    strUsage += "  -change=<address>      " + _("Send change only to the specified address(es)") + "\n" +
     strUsage += "  -spendzeroconfchange   " + _("Spend unconfirmed change when sending transactions (default: 1)") + "\n";
 #endif
     strUsage += "\n" + _("Block creation options:") + "\n";
@@ -559,6 +562,20 @@ bool AppInit2(boost::thread_group& threadGroup)
         if (nTransactionFee > 25 * COIN)
             InitWarning(_("Warning: -paytxfee is set very high! This is the transaction fee you will pay if you send a transaction."));
     }
+    
+    if (mapArgs.count("-change"))
+    {
+        BOOST_FOREACH(std::string strChange, mapMultiArgs["-change"]) {
+            CBitcoinAddress address(strChange);
+            CKeyID keyID;
+            
+            if (!address.GetKeyID(keyID)) {
+                return InitError(strprintf(_("Bad -change address: '%s'"), strChange));
+            }
+            AddFixedChangeAddress(keyID);
+        }
+    }
+    
     bSpendZeroConfChange = GetArg("-spendzeroconfchange", true);
 
     strWalletFile = GetArg("-wallet", "wallet.dat");

src/wallet.cpp

@@ -18,6 +18,7 @@ using namespace std;
 // Settings
 int64_t nTransactionFee = 0;
 bool bSpendZeroConfChange = true;
+static std::vector<CKeyID> vChangeAddresses;
 
 //////////////////////////////////////////////////////////////////////////////
 //
@@ -1398,17 +1399,10 @@ bool CWallet::CreateTransaction(const vector<pair<CScript, int64_t> >& vecSend,
                     if (coinControl && !boost::get<CNoDestination>(&coinControl->destChange))
                         scriptChange.SetDestination(coinControl->destChange);
                         
-                    // send change to one of the specified change addresses
-                    else if (mapArgs.count("-change") && mapMultiArgs["-change"].size() > 0)
+                    // send change to one of the specified change addresses, if specified at init
+                    else if (vChangeAddresses.size())
                     {
-                        CBitcoinAddress address(mapMultiArgs["-change"][GetRandInt(mapMultiArgs["-change"].size())]);
-
-                        CKeyID keyID;
-                        if (!address.GetKeyID(keyID)) {
-                            strFailReason = _("Bad change address");
-                            return false;
-                        }
-
+                        CKeyID keyID = vChangeAddresses[GetRandInt(vChangeAddresses.size())];
                         scriptChange.SetDestination(keyID);
                     }
 
@@ -2197,3 +2191,11 @@ bool CWallet::GetDestData(const CTxDestination &dest, const std::string &key, st
     }
     return false;
 }
+
+// Add an address to the list of fixed change addresses to use. Fixed
+// addresses can be used to reduce the pace at which wallets expand
+// due to number of change addresses
+void AddFixedChangeAddress(const CKeyID &changeAddress)
+{
+    vChangeAddresses.push_back(changeAddress);
+}

src/wallet.h

@@ -53,6 +53,9 @@ static void WriteOrderPos(const int64_t& nOrderPos, mapValue_t& mapValue)
     mapValue["n"] = i64tostr(nOrderPos);
 }
 
+// Add an address to the list of fixed change addresses to use.
+void AddFixedChangeAddress(const CKeyID &changeAddress);
+
 /** (client) version numbers for particular wallet features */
 enum WalletFeature
 {