Disable "limit virtual memory" routine on macOS

This has no effect on macOS.
https://stackoverflow.com/questions/3274385/how-to-limit-memory-of-a-os-x-program-ulimit-v-neither-m-are-working

Closes #18656.
PR  #19805.

src/app/application.cpp

@@ -373,7 +373,7 @@ void Application::setMemoryWorkingSetLimit(const int size)
         return;
 
     m_storeMemoryWorkingSetLimit = size;
-#ifdef QBT_USES_LIBTORRENT2
+#if defined(QBT_USES_LIBTORRENT2) && !defined(Q_OS_MACOS)
     applyMemoryWorkingSetLimit();
 #endif
 }
@@ -782,7 +782,7 @@ int Application::exec()
     printf("%s\n", qUtf8Printable(loadingStr));
 #endif
 
-#ifdef QBT_USES_LIBTORRENT2
+#if defined(QBT_USES_LIBTORRENT2) && !defined(Q_OS_MACOS)
     applyMemoryWorkingSetLimit();
 #endif
 
@@ -1134,7 +1134,7 @@ void Application::shutdownCleanup([[maybe_unused]] QSessionManager &manager)
 }
 #endif
 
-#ifdef QBT_USES_LIBTORRENT2
+#if defined(QBT_USES_LIBTORRENT2) && !defined(Q_OS_MACOS)
 void Application::applyMemoryWorkingSetLimit() const
 {
     const size_t MiB = 1024 * 1024;

src/app/application.h

@@ -159,7 +159,7 @@ private:
     void runExternalProgram(const QString &programTemplate, const BitTorrent::Torrent *torrent) const;
     void sendNotificationEmail(const BitTorrent::Torrent *torrent);
 
-#ifdef QBT_USES_LIBTORRENT2
+#if defined(QBT_USES_LIBTORRENT2) && !defined(Q_OS_MACOS)
     void applyMemoryWorkingSetLimit() const;
 #endif
 

src/gui/advancedsettings.cpp

@@ -63,7 +63,7 @@ namespace
         // qBittorrent section
         QBITTORRENT_HEADER,
         RESUME_DATA_STORAGE,
-#ifdef QBT_USES_LIBTORRENT2
+#if defined(QBT_USES_LIBTORRENT2) && !defined(Q_OS_MACOS)
         MEMORY_WORKING_SET_LIMIT,
 #endif
 #if defined(Q_OS_WIN)
@@ -197,7 +197,7 @@ void AdvancedSettings::saveAdvancedSettings() const
     BitTorrent::Session *const session = BitTorrent::Session::instance();
 
     session->setResumeDataStorageType(m_comboBoxResumeDataStorage.currentData().value<BitTorrent::ResumeDataStorageType>());
-#ifdef QBT_USES_LIBTORRENT2
+#if defined(QBT_USES_LIBTORRENT2) && !defined(Q_OS_MACOS)
     // Physical memory (RAM) usage limit
     app()->setMemoryWorkingSetLimit(m_spinBoxMemoryWorkingSetLimit.value());
 #endif
@@ -456,7 +456,7 @@ void AdvancedSettings::loadAdvancedSettings()
     m_comboBoxResumeDataStorage.setCurrentIndex(m_comboBoxResumeDataStorage.findData(QVariant::fromValue(session->resumeDataStorageType())));
     addRow(RESUME_DATA_STORAGE, tr("Resume data storage type (requires restart)"), &m_comboBoxResumeDataStorage);
 
-#ifdef QBT_USES_LIBTORRENT2
+#if defined(QBT_USES_LIBTORRENT2) && !defined(Q_OS_MACOS)
     // Physical memory (RAM) usage limit
     m_spinBoxMemoryWorkingSetLimit.setMinimum(1);
     m_spinBoxMemoryWorkingSetLimit.setMaximum(std::numeric_limits<int>::max());

src/gui/advancedsettings.h

@@ -30,6 +30,7 @@
 
 #include <libtorrent/config.hpp>
 
+#include <QtSystemDetection>
 #include <QCheckBox>
 #include <QComboBox>
 #include <QLineEdit>
@@ -88,7 +89,11 @@ private:
     QCheckBox m_checkBoxCoalesceRW;
 #else
     QComboBox m_comboBoxDiskIOType;
-    QSpinBox m_spinBoxMemoryWorkingSetLimit, m_spinBoxHashingThreads;
+    QSpinBox m_spinBoxHashingThreads;
+#endif
+
+#if defined(QBT_USES_LIBTORRENT2) && !defined(Q_OS_MACOS)
+    QSpinBox m_spinBoxMemoryWorkingSetLimit;
 #endif
 
 #if defined(QBT_USES_LIBTORRENT2) && TORRENT_USE_I2P