feat: Added basic ability to interrupt long running tasks

lib/libimhex/source/api/task.cpp

@@ -6,66 +6,174 @@
 
 namespace hex {
 
-    std::list<Task *> Task::s_runningTasks;
-    std::mutex Task::s_taskMutex;
+    std::mutex TaskManager::s_deferredCallsMutex;
 
-    Task::Task(const std::string &unlocalizedName, u64 maxValue) : m_name(LangEntry(unlocalizedName)), m_maxValue(maxValue), m_currValue(0) {
-        std::scoped_lock lock(Task::s_taskMutex);
+    std::list<std::shared_ptr<Task>> TaskManager::s_tasks;
+    std::list<std::function<void()>> TaskManager::s_deferredCalls;
 
-        Task::s_runningTasks.push_back(this);
-    }
+    Task::Task(std::string unlocalizedName, u64 maxValue, std::function<void(Task &)> function)
+    : m_unlocalizedName(std::move(unlocalizedName)), m_currValue(0), m_maxValue(maxValue) {
+        this->m_thread = std::thread([this, func = std::move(function)] {
+            try {
+                func(*this);
+            } catch (const TaskInterruptor &) {
+                this->interruption();
+            } catch (...) {
+                this->exception();
+            }
 
-    Task::~Task() {
-        this->finish();
+            this->finish();
+        });
     }
 
     Task::Task(hex::Task &&other) noexcept {
-        std::scoped_lock lock(Task::s_taskMutex);
+        std::scoped_lock thisLock(this->m_mutex);
+        std::scoped_lock otherLock(other.m_mutex);
+
+        this->m_thread = std::move(other.m_thread);
+        this->m_unlocalizedName = std::move(other.m_unlocalizedName);
 
-        this->m_name = other.m_name;
         this->m_maxValue = other.m_maxValue;
         this->m_currValue = other.m_currValue;
 
-        auto it = std::find(Task::s_runningTasks.begin(), Task::s_runningTasks.end(), &other);
-        if (it != Task::s_runningTasks.end()) {
-            *it = this;
-        }
+        this->m_finished = other.m_finished;
+        this->m_hadException = other.m_hadException;
+        this->m_interrupted = other.m_interrupted;
+        this->m_shouldInterrupt = other.m_shouldInterrupt;
+    }
+
+    Task::~Task() {
+        this->interrupt();
+        this->m_thread.join();
+    }
+
+    void Task::update(u64 value) {
+        std::scoped_lock lock(this->m_mutex);
+
+        this->m_currValue = value;
+
+        if (this->m_shouldInterrupt)
+            throw TaskInterruptor();
+    }
+
+    void Task::setMaxValue(u64 value) {
+        std::scoped_lock lock(this->m_mutex);
+
+        this->m_maxValue = value;
+    }
+
+
+    void Task::interrupt() {
+        std::scoped_lock lock(this->m_mutex);
+
+        this->m_shouldInterrupt = true;
+    }
+
+    bool Task::isFinished() const {
+        std::scoped_lock lock(this->m_mutex);
+
+        return this->m_finished;
+    }
+
+    bool Task::hadException() const {
+        std::scoped_lock lock(this->m_mutex);
+
+        return this->m_hadException;
+    }
+
+    bool Task::wasInterrupted() const {
+        std::scoped_lock lock(this->m_mutex);
+
+        return this->m_interrupted;
+    }
+
+    void Task::clearException() {
+        std::scoped_lock lock(this->m_mutex);
+
+        this->m_hadException = false;
+    }
+
+    const std::string &Task::getUnlocalizedName() {
+        return this->m_unlocalizedName;
+    }
+
+    u64 Task::getValue() const {
+        return this->m_currValue;
+    }
+
+    u64 Task::getMaxValue() const {
+        return this->m_maxValue;
     }
 
     void Task::finish() {
-        std::scoped_lock lock(Task::s_taskMutex);
+        std::scoped_lock lock(this->m_mutex);
 
-        Task::s_runningTasks.remove(this);
+        this->m_finished = true;
     }
 
-    void Task::setMaxValue(u64 maxValue) {
-        this->m_maxValue = maxValue;
+    void Task::interruption() {
+        std::scoped_lock lock(this->m_mutex);
+
+        this->m_interrupted = true;
     }
 
-    void Task::update(u64 currValue) {
-        if (this->m_currValue < this->m_maxValue)
-            this->m_currValue = currValue;
+    void Task::exception() {
+        std::scoped_lock lock(this->m_mutex);
+
+        this->m_hadException = true;
     }
 
-    double Task::getProgress() const {
-        if (this->m_maxValue == 0)
-            return 100;
 
-        return static_cast<double>(this->m_currValue) / static_cast<double>(this->m_maxValue);
+    bool TaskHolder::isRunning() const {
+        return !m_task.expired() && !m_task.lock()->isFinished();
     }
 
-    bool Task::isPending() const {
-        return this->m_maxValue == 0;
+    bool TaskHolder::hadException() const {
+        return m_task.expired() || m_task.lock()->hadException();
     }
 
-    const std::string &Task::getName() const {
-        return this->m_name;
+    bool TaskHolder::wasInterrupted() const {
+        return m_task.expired() || m_task.lock()->wasInterrupted();
     }
 
-    size_t Task::getRunningTaskCount() {
-        std::scoped_lock lock(Task::s_taskMutex);
+    void TaskHolder::interrupt() {
+        if (!this->m_task.expired())
+            this->m_task.lock()->interrupt();
+    }
 
-        return Task::s_runningTasks.size();
+
+    TaskHolder TaskManager::createTask(std::string name, u64 maxValue, std::function<void(Task &)> function) {
+        s_tasks.emplace_back(std::make_shared<Task>(std::move(name), maxValue, std::move(function)));
+
+        return TaskHolder(s_tasks.back());
+    }
+
+    void TaskManager::collectGarbage() {
+        std::erase_if(s_tasks, [](const auto &task) { return task->isFinished() && !task->hadException(); });
+    }
+
+    std::list<std::shared_ptr<Task>> &TaskManager::getRunningTasks() {
+        return s_tasks;
+    }
+
+    size_t TaskManager::getRunningTaskCount() {
+        return s_tasks.size();
+    }
+
+
+    void TaskManager::doLater(const std::function<void()> &function) {
+        std::scoped_lock lock(s_deferredCallsMutex);
+
+        s_deferredCalls.push_back(function);
+    }
+
+    void TaskManager::runDeferredCalls() {
+        std::scoped_lock lock(s_deferredCallsMutex);
+
+        for (const auto &call : s_deferredCalls)
+            call();
+
+        s_deferredCalls.clear();
     }
 
 }