Fix permanent critical memory state.

src/app/GUI/usagewidget.cpp

@@ -20,6 +20,7 @@
 #include "Private/Tasks/taskscheduler.h"
 #include "Private/Tasks/complextask.h"
 #include "conncontextptr.h"
+#include "memoryhandler.h"
 
 #include <QTimer>
 #include <QLocale>
@@ -146,6 +147,13 @@ UsageWidget::UsageWidget(QWidget * const parent) : QStatusBar(parent) {
 
     mRamLabel = new QLabel(this);
 
+    const auto clearRamButton = new QPushButton("clear memory", this);
+    connect(clearRamButton, &QPushButton::clicked,
+            this, []() {
+        const auto m = MemoryHandler::sInstance;
+        m->clearMemory();
+    });
+
     addPermanentWidget(gpuLabel);
     addPermanentWidget(mGpuBar);
 
@@ -160,6 +168,8 @@ UsageWidget::UsageWidget(QWidget * const parent) : QStatusBar(parent) {
 
     addPermanentWidget(mRamLabel);
 
+    addPermanentWidget(clearRamButton);
+
     setThreadsTotal(QThread::idealThreadCount());
 
     connect(TaskScheduler::instance(), &TaskScheduler::hddUsageChanged,
@@ -200,7 +210,7 @@ void UsageWidget::setTotalRam(const qreal totalRamMB) {
 }
 
 void UsageWidget::addComplexTask(ComplexTask * const task) {
-    for(const auto wid : mTaskWidgets) {
+    for(const auto wid : qAsConst(mTaskWidgets)) {
         if(wid->isHidden()) {
             return wid->setComplexTask(task);
         }

src/app/memorychecker.cpp

@@ -164,7 +164,7 @@ void MemoryChecker::checkMemory() {
     } else if(procFreeKB.fValue < 0) {
         emit handleMemoryState(LOW_MEMORY_STATE, longB(-procFreeKB));
         mLastMemoryState = LOW_MEMORY_STATE;
-    } else if(mLastMemoryState != NORMAL_MEMORY_STATE) {
+    } else/* if(mLastMemoryState != NORMAL_MEMORY_STATE)*/ {
         emit handleMemoryState(NORMAL_MEMORY_STATE, longB(0));
         mLastMemoryState = NORMAL_MEMORY_STATE;
     }

src/app/memoryhandler.cpp

@@ -60,6 +60,10 @@ MemoryHandler::~MemoryHandler() {
     delete mMemoryChecker;
 }
 
+void MemoryHandler::clearMemory() {
+    freeMemory(NORMAL_MEMORY_STATE, longB(std::numeric_limits<qint64>::max()));
+}
+
 MemoryState MemoryHandler::sMemoryState() {
     return sInstance->mMemoryState;
 }
@@ -90,11 +94,11 @@ void MemoryHandler::freeMemory(const MemoryState newState,
         const auto cont = mDataHandler.takeFirst();
         memToFree -= cont->free_RAM_k();
     }
-    if(newState == CRITICAL_MEMORY_STATE) {
+    if(newState == CRITICAL_MEMORY_STATE ||
+       memToFree > 0) {
+        mMemoryState = CRITICAL_MEMORY_STATE;
         emit enteredCriticalState();
         emit allMemoryUsed();
-    } else if(memToFree > 0) {
-        emit allMemoryUsed();
     }
     emit memoryFreed();
 }

src/app/memoryhandler.h

@@ -26,6 +26,8 @@ public:
     explicit MemoryHandler(QObject * const parent = nullptr);
     ~MemoryHandler();
 
+    void clearMemory();
+
     static MemoryHandler *sInstance;
     static MemoryState sMemoryState();
 signals:

src/core/FileCacheHandlers/imagecachehandler.cpp

@@ -89,11 +89,11 @@ void ImageLoader::process() {
 }
 
 void ImageLoader::afterProcessing() {
-    mTargetHandler->replaceImage(mImage);
+    if(mTargetHandler) mTargetHandler->replaceImage(mImage);
 }
 
 void ImageLoader::afterCanceled() {
-    mTargetHandler->replaceImage(mImage);
+    if(mTargetHandler) mTargetHandler->replaceImage(mImage);
 }
 
 void OraLoader::process() {

src/core/FileCacheHandlers/imagecachehandler.h

@@ -33,7 +33,7 @@ public:
     void afterProcessing();
     void afterCanceled();
 protected:
-    ImageFileDataHandler * const mTargetHandler;
+    const qptr<ImageFileDataHandler> mTargetHandler;
     const QString mFilePath;
     sk_sp<SkImage> mImage;
 };