From 5d66d0a11e84cb447881dcabccb2084bc0686adc Mon Sep 17 00:00:00 2001
From: Pieter Wuille <pieter.wuille@gmail.com>
Date: Fri, 24 Jun 2016 16:35:21 +0200
Subject: [PATCH] Do not ask a UI question from bitcoind

---
 src/init.cpp          | 3 ++-
 src/noui.cpp          | 6 ++++++
 src/qt/bitcoingui.cpp | 2 ++
 src/ui_interface.h    | 3 +++
 4 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/src/init.cpp b/src/init.cpp
index 7a4fe6e60..de42cd376 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -1341,8 +1341,9 @@ bool AppInit2(boost::thread_group& threadGroup, CScheduler& scheduler)
         if (!fLoaded) {
             // first suggest a reindex
             if (!fReset) {
-                bool fRet = uiInterface.ThreadSafeMessageBox(
+                bool fRet = uiInterface.ThreadSafeQuestion(
                     strLoadError + ".\n\n" + _("Do you want to rebuild the block database now?"),
+                    strLoadError + ".\nPlease restart with -reindex or -reindex-chainstate to recover.",
                     "", CClientUIInterface::MSG_ERROR | CClientUIInterface::BTN_ABORT);
                 if (fRet) {
                     fReindex = true;
diff --git a/src/noui.cpp b/src/noui.cpp
index 3a7736191..0d9207c11 100644
--- a/src/noui.cpp
+++ b/src/noui.cpp
@@ -39,6 +39,11 @@ static bool noui_ThreadSafeMessageBox(const std::string& message, const std::str
     return false;
 }
 
+static bool noui_ThreadSafeQuestion(const std::string& /* ignored interactive message */, const std::string& message, const std::string& caption, unsigned int style)
+{
+    return noui_ThreadSafeMessageBox(message, caption, style);
+}
+
 static void noui_InitMessage(const std::string& message)
 {
     LogPrintf("init message: %s\n", message);
@@ -48,5 +53,6 @@ void noui_connect()
 {
     // Connect bitcoind signal handlers
     uiInterface.ThreadSafeMessageBox.connect(noui_ThreadSafeMessageBox);
+    uiInterface.ThreadSafeQuestion.connect(noui_ThreadSafeQuestion);
     uiInterface.InitMessage.connect(noui_InitMessage);
 }
diff --git a/src/qt/bitcoingui.cpp b/src/qt/bitcoingui.cpp
index fa5083e00..0dbc15b47 100644
--- a/src/qt/bitcoingui.cpp
+++ b/src/qt/bitcoingui.cpp
@@ -1040,12 +1040,14 @@ void BitcoinGUI::subscribeToCoreSignals()
 {
     // Connect signals to client
     uiInterface.ThreadSafeMessageBox.connect(boost::bind(ThreadSafeMessageBox, this, _1, _2, _3));
+    uiInterface.ThreadSafeQuestion.connect(boost::bind(ThreadSafeMessageBox, this, _1, _3, _4));
 }
 
 void BitcoinGUI::unsubscribeFromCoreSignals()
 {
     // Disconnect signals from client
     uiInterface.ThreadSafeMessageBox.disconnect(boost::bind(ThreadSafeMessageBox, this, _1, _2, _3));
+    uiInterface.ThreadSafeQuestion.disconnect(boost::bind(ThreadSafeMessageBox, this, _1, _3, _4));
 }
 
 UnitDisplayStatusBarControl::UnitDisplayStatusBarControl() :
diff --git a/src/ui_interface.h b/src/ui_interface.h
index 32a92a4b8..ee0fd9113 100644
--- a/src/ui_interface.h
+++ b/src/ui_interface.h
@@ -75,6 +75,9 @@ public:
     /** Show message box. */
     boost::signals2::signal<bool (const std::string& message, const std::string& caption, unsigned int style), boost::signals2::last_value<bool> > ThreadSafeMessageBox;
 
+    /** If possible, ask the user a question. If not, falls back to ThreadSafeMessageBox(noninteractive_message, caption, style) and returns false. */
+    boost::signals2::signal<bool (const std::string& message, const std::string& noninteractive_message, const std::string& caption, unsigned int style), boost::signals2::last_value<bool> > ThreadSafeQuestion;
+
     /** Progress message during initialization. */
     boost::signals2::signal<void (const std::string &message)> InitMessage;