port expired transaction notify from Zcash. Issue #110

src/init.cpp

@@ -399,6 +399,7 @@ std::string HelpMessage(HelpMessageMode mode)
 #ifndef _WIN32
     strUsage += HelpMessageOpt("-pid=<file>", strprintf(_("Specify pid file (default: %s)"), "komodod.pid"));
 #endif
+    strUsage += HelpMessageOpt("-txexpirynotify=<cmd>", _("Execute command when transaction expires (%s in cmd is replaced by transaction id)"));
     strUsage += HelpMessageOpt("-prune=<n>", strprintf(_("Reduce storage requirements by pruning (deleting) old blocks. This mode disables wallet support and is incompatible with -txindex. "
             "Warning: Reverting this setting requires re-downloading the entire blockchain. "
             "(default: 0 = disable pruning blocks, >%u = target size in MiB to use for block files)"), MIN_DISK_SPACE_FOR_BLOCK_FILES / 1024 / 1024));
@@ -618,6 +619,14 @@ static void BlockNotifyCallback(const uint256& hashNewTip)
     boost::thread t(runCommand, strCmd); // thread runs free
 }
 
+static void TxExpiryNotifyCallback(const uint256& txid)
+{
+    std::string strCmd = GetArg("-txexpirynotify", "");
+
+    boost::replace_all(strCmd, "%s", txid.GetHex());
+    boost::thread t(runCommand, strCmd); // thread runs free
+}
+
 struct CImportingNow
 {
     CImportingNow() {
@@ -2114,6 +2123,8 @@ bool AppInit2(boost::thread_group& threadGroup, CScheduler& scheduler)
 
     if (mapArgs.count("-blocknotify"))
         uiInterface.NotifyBlockTip.connect(BlockNotifyCallback);
+     if (mapArgs.count("-txexpirynotify"))
+        uiInterface.NotifyTxExpiration.connect(TxExpiryNotifyCallback);
     if ( KOMODO_REWIND >= 0 )
     {
         uiInterface.InitMessage(_("Activating best chain..."));