From c7b6117debf4ebabc464a55b840bdd7bdeb94fa3 Mon Sep 17 00:00:00 2001
From: Jeff Garzik <jgarzik@bitpay.com>
Date: Thu, 14 Aug 2014 12:32:34 -0400
Subject: [PATCH] Create new signal for notification of new blocks.  Use w/
 -blocknotify

---
 src/init.cpp       | 11 +++++++++++
 src/main.cpp       |  8 +++-----
 src/ui_interface.h |  3 +++
 3 files changed, 17 insertions(+), 5 deletions(-)

diff --git a/src/init.cpp b/src/init.cpp
index 8ae228bbbe..494342c693 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -367,6 +367,14 @@ std::string LicenseInfo()
            "\n";
 }
 
+static void BlockNotifyCallback(const uint256& hashNewTip)
+{
+    std::string strCmd = GetArg("-blocknotify", "");
+
+    boost::replace_all(strCmd, "%s", hashNewTip.GetHex());
+    boost::thread t(runCommand, strCmd); // thread runs free
+}
+
 struct CImportingNow
 {
     CImportingNow() {
@@ -1184,6 +1192,9 @@ bool AppInit2(boost::thread_group& threadGroup)
 #endif // !ENABLE_WALLET
     // ********************************************************* Step 9: import blocks
 
+    if (mapArgs.count("-blocknotify"))
+        uiInterface.NotifyBlockTip.connect(BlockNotifyCallback);
+
     // scan for better chains in the block chain database, that are not yet connected in the active best chain
     CValidationState state;
     if (!ActivateBestChain(state))
diff --git a/src/main.cpp b/src/main.cpp
index e73942d7e0..841cc1952f 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -2162,16 +2162,14 @@ bool ActivateBestChain(CValidationState &state) {
             uint256 hashNewTip = pindexNewTip->GetBlockHash();
             // Relay inventory, but don't relay old inventory during initial block download.
             int nBlockEstimate = Checkpoints::GetTotalBlocksEstimate();
+            {
             LOCK(cs_vNodes);
             BOOST_FOREACH(CNode* pnode, vNodes)
                 if (chainActive.Height() > (pnode->nStartingHeight != -1 ? pnode->nStartingHeight - 2000 : nBlockEstimate))
                     pnode->PushInventory(CInv(MSG_BLOCK, hashNewTip));
-
-            std::string strCmd = GetArg("-blocknotify", "");
-            if (!strCmd.empty()) {
-                boost::replace_all(strCmd, "%s", hashNewTip.GetHex());
-                boost::thread t(runCommand, strCmd); // thread runs free
             }
+
+            uiInterface.NotifyBlockTip(hashNewTip);
         }
     } while(pindexMostWork != chainActive.Tip());
 
diff --git a/src/ui_interface.h b/src/ui_interface.h
index a073a32828..bbc8a203c9 100644
--- a/src/ui_interface.h
+++ b/src/ui_interface.h
@@ -92,6 +92,9 @@ public:
 
     /** Show progress e.g. for verifychain */
     boost::signals2::signal<void (const std::string &title, int nProgress)> ShowProgress;
+
+    /** New block has been accepted */
+    boost::signals2::signal<void (const uint256& hash)> NotifyBlockTip;
 };
 
 extern CClientUIInterface uiInterface;