5 files changed, 116 insertions, 1 deletions
diff --git a/src/Makefile.qt.include b/src/Makefile.qt.include
index 3ca2a7451d..73538e8bc9 100644
--- a/src/Makefile.qt.include
+++ b/src/Makefile.qt.include
@@ -162,7 +162,8 @@ QT_MOC_CPP = \
 
 BITCOIN_MM = \
   qt/macdockiconhandler.mm \
-  qt/macnotificationhandler.mm
+  qt/macnotificationhandler.mm \
+  qt/macos_appnap.mm
 
 QT_MOC = \
   qt/bitcoin.moc \
@@ -205,6 +206,7 @@ BITCOIN_QT_H = \
   qt/intro.h \
   qt/macdockiconhandler.h \
   qt/macnotificationhandler.h \
+  qt/macos_appnap.h \
   qt/modaloverlay.h \
   qt/networkstyle.h \
   qt/notificator.h \
diff --git a/src/qt/bitcoingui.cpp b/src/qt/bitcoingui.cpp
index 311841017f..1e80777c15 100644
--- a/src/qt/bitcoingui.cpp
+++ b/src/qt/bitcoingui.cpp
@@ -211,6 +211,10 @@ BitcoinGUI::BitcoinGUI(interfaces::Node& node, const PlatformStyle *_platformSty
         connect(progressBar, &GUIUtil::ClickableProgressBar::clicked, this, &BitcoinGUI::showModalOverlay);
     }
 #endif
+
+#ifdef Q_OS_MAC
+    m_app_nap_inhibitor = new CAppNapInhibitor;
+#endif
 }
 
 BitcoinGUI::~BitcoinGUI()
@@ -223,6 +227,7 @@ BitcoinGUI::~BitcoinGUI()
     if(trayIcon) // Hide tray icon, as deleting will let it linger until quit (on Ubuntu)
         trayIcon->hide();
 #ifdef Q_OS_MAC
+    delete m_app_nap_inhibitor;
     delete appMenuBar;
     MacDockIconHandler::cleanup();
 #endif
@@ -786,6 +791,11 @@ void BitcoinGUI::openOptionsDialogWithTab(OptionsDialog::Tab tab)
 
 void BitcoinGUI::setNumBlocks(int count, const QDateTime& blockDate, double nVerificationProgress, bool header)
 {
+// Disabling macOS App Nap on initial sync, disk and reindex operations.
+#ifdef Q_OS_MAC
+    (m_node.isInitialBlockDownload() || m_node.getReindex() || m_node.getImporting()) ? m_app_nap_inhibitor->disableAppNap() : m_app_nap_inhibitor->enableAppNap();
+#endif
+
     if (modalOverlay)
     {
         if (header)
diff --git a/src/qt/bitcoingui.h b/src/qt/bitcoingui.h
index dcaca10557..57b70803ae 100644
--- a/src/qt/bitcoingui.h
+++ b/src/qt/bitcoingui.h
@@ -20,6 +20,10 @@
 #include <QPoint>
 #include <QSystemTrayIcon>
 
+#ifdef Q_OS_MAC
+#include <qt/macos_appnap.h>
+#endif
+
 #include <memory>
 
 class ClientModel;
@@ -143,6 +147,10 @@ private:
     HelpMessageDialog* helpMessageDialog = nullptr;
     ModalOverlay* modalOverlay = nullptr;
 
+#ifdef Q_OS_MAC
+    CAppNapInhibitor* m_app_nap_inhibitor = nullptr;
+#endif
+
     /** Keep track of previous number of blocks, to detect progress */
     int prevBlocks = 0;
     int spinnerFrame = 0;
diff --git a/src/qt/macos_appnap.h b/src/qt/macos_appnap.h
new file mode 100644
index 0000000000..8c2cd840b0
--- /dev/null
+++ b/src/qt/macos_appnap.h
@@ -0,0 +1,24 @@
+// Copyright (c) 2011-2018 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef BITCOIN_QT_MACOS_APPNAP_H
+#define BITCOIN_QT_MACOS_APPNAP_H
+
+#include <memory>
+
+class CAppNapInhibitor final
+{
+public:
+    explicit CAppNapInhibitor();
+    ~CAppNapInhibitor();
+
+    void disableAppNap();
+    void enableAppNap();
+
+private:
+    class CAppNapImpl;
+    std::unique_ptr<CAppNapImpl> impl;
+};
+
+#endif // BITCOIN_QT_MACOS_APPNAP_H
diff --git a/src/qt/macos_appnap.mm b/src/qt/macos_appnap.mm
new file mode 100644
index 0000000000..22a88782ab
--- /dev/null
+++ b/src/qt/macos_appnap.mm
@@ -0,0 +1,71 @@
+// Copyright (c) 2011-2018 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include "macos_appnap.h"
+
+#include <AvailabilityMacros.h>
+#include <Foundation/NSProcessInfo.h>
+#include <Foundation/Foundation.h>
+
+class CAppNapInhibitor::CAppNapImpl
+{
+public:
+    ~CAppNapImpl()
+    {
+        if(activityId)
+            enableAppNap();
+    }
+
+    void disableAppNap()
+    {
+        if (!activityId)
+        {
+            @autoreleasepool {
+                const NSActivityOptions activityOptions =
+                NSActivityUserInitiatedAllowingIdleSystemSleep &
+                ~(NSActivitySuddenTerminationDisabled |
+                NSActivityAutomaticTerminationDisabled);
+
+                id processInfo = [NSProcessInfo processInfo];
+                if ([processInfo respondsToSelector:@selector(beginActivityWithOptions:reason:)])
+                {
+                    activityId = [processInfo beginActivityWithOptions: activityOptions reason:@"Temporarily disable App Nap for bitcoin-qt."];
+                    [activityId retain];
+                }
+            }
+        }
+    }
+
+    void enableAppNap()
+    {
+        if(activityId)
+        {
+            @autoreleasepool {
+                id processInfo = [NSProcessInfo processInfo];
+                if ([processInfo respondsToSelector:@selector(endActivity:)])
+                    [processInfo endActivity:activityId];
+
+                [activityId release];
+                activityId = nil;
+            }
+        }
+    }
+
+private:
+    NSObject* activityId;
+};
+
+CAppNapInhibitor::CAppNapInhibitor() : impl(new CAppNapImpl()) {}
+
+CAppNapInhibitor::~CAppNapInhibitor() = default;
+
+void CAppNapInhibitor::disableAppNap()
+{
+    impl->disableAppNap();
+}
+
+void CAppNapInhibitor::enableAppNap()
+{
+    impl->enableAppNap();
+}