Wait primitives.

src/xenia/base/threading.h

@@ -14,9 +14,11 @@
 #include <chrono>
 #include <condition_variable>
 #include <cstdint>
+#include <memory>
 #include <mutex>
 #include <string>
 #include <thread>
+#include <vector>
 
 namespace xe {
 namespace threading {
@@ -67,15 +69,107 @@ void Sleep(std::chrono::duration<Rep, Period> duration) {
   Sleep(std::chrono::duration_cast<std::chrono::microseconds>(duration));
 }
 
+// Results for a WaitHandle operation.
+enum class WaitResult {
+  // The state of the specified object is signaled.
+  // In a WaitAny the tuple will contain the index of the wait handle that
+  // caused the wait to be satisfied.
+  kSuccess,
+  // The wait was ended by one or more user-mode callbacks queued to the thread.
+  // This will occur when is_alertable is set true.
+  kUserCallback,
+  // The time-out interval elapsed, and the object's state is nonsignaled.
+  kTimeout,
+  // The specified object is a mutex object that was not released by the thread
+  // that owned the mutex object before the owning thread terminated. Ownership
+  // of the mutex object is granted to the calling thread and the mutex is set
+  // to nonsignaled.
+  // In a WaitAny the tuple will contain the index of the wait handle that
+  // caused the wait to be abandoned.
+  kAbandoned,
+  // The function has failed.
+  kFailed,
+};
+
 class WaitHandle {
  public:
-  // bool Wait();
-  // static bool Wait();
-  // static bool SignalAndWait();
-  // static bool WaitMultiple();
+  virtual ~WaitHandle() = default;
+
+  // Waits until the wait handle is in the signaled state, an alert triggers and
+  // a user callback is queued to the thread, or the timeout interval elapses.
+  // If timeout is zero the call will return immediately instead of waiting and
+  // if the timeout is max() the wait will not time out.
+  inline WaitResult Wait(
+      bool is_alertable,
+      std::chrono::milliseconds timeout = std::chrono::milliseconds::max()) {
+    return WaitHandle::Wait(this, is_alertable, timeout);
+  }
+
+  // Waits until the wait handle is in the signaled state, an alert triggers and
+  // a user callback is queued to the thread, or the timeout interval elapses.
+  // If timeout is zero the call will return immediately instead of waiting and
+  // if the timeout is max() the wait will not time out.
+  static WaitResult Wait(
+      WaitHandle* wait_handle, bool is_alertable,
+      std::chrono::milliseconds timeout = std::chrono::milliseconds::max());
+
+  // Signals one object and waits on another object as a single operation.
+  // Waits until the wait handle is in the signaled state, an alert triggers and
+  // a user callback is queued to the thread, or the timeout interval elapses.
+  // If timeout is zero the call will return immediately instead of waiting and
+  // if the timeout is max() the wait will not time out.
+  static WaitResult SignalAndWait(
+      WaitHandle* wait_handle_to_signal, WaitHandle* wait_handle_to_wait_on,
+      bool is_alertable,
+      std::chrono::milliseconds timeout = std::chrono::milliseconds::max());
+
+  // Waits until all of the specified objects are in the signaled state, a
+  // user callback is queued to the thread, or the time-out interval elapses.
+  // If timeout is zero the call will return immediately instead of waiting and
+  // if the timeout is max() the wait will not time out.
+  inline static WaitResult WaitAll(
+      WaitHandle* wait_handles[], size_t wait_handle_count, bool is_alertable,
+      std::chrono::milliseconds timeout = std::chrono::milliseconds::max()) {
+    return WaitMultiple(wait_handles, wait_handle_count, true, is_alertable,
+                        timeout).first;
+  }
+  inline static WaitResult WaitAll(
+      std::vector<WaitHandle*> wait_handles, bool is_alertable,
+      std::chrono::milliseconds timeout = std::chrono::milliseconds::max()) {
+    return WaitAll(wait_handles.data(), wait_handles.size(), is_alertable,
+                   timeout);
+  }
+
+  // Waits until any of the specified objects are in the signaled state, a
+  // user callback is queued to the thread, or the time-out interval elapses.
+  // If timeout is zero the call will return immediately instead of waiting and
+  // if the timeout is max() the wait will not time out.
+  // The second argument of the return tuple indicates which wait handle caused
+  // the wait to be satisfied or abandoned.
+  inline static std::pair<WaitResult, size_t> WaitAny(
+      WaitHandle* wait_handles[], size_t wait_handle_count, bool is_alertable,
+      std::chrono::milliseconds timeout = std::chrono::milliseconds::max()) {
+    return WaitMultiple(wait_handles, wait_handle_count, false, is_alertable,
+                        timeout);
+  }
+  inline static std::pair<WaitResult, size_t> WaitAny(
+      std::vector<WaitHandle*> wait_handles, bool is_alertable,
+      std::chrono::milliseconds timeout = std::chrono::milliseconds::max()) {
+    return WaitAny(wait_handles.data(), wait_handles.size(), is_alertable,
+                   timeout);
+  }
 
  protected:
   WaitHandle() = default;
+
+  // Returns the native handle of the object on the host system.
+  // This value is platform specific.
+  virtual void* native_handle() const = 0;
+
+  static std::pair<WaitResult, size_t> WaitMultiple(
+      WaitHandle* wait_handles[], size_t wait_handle_count, bool wait_all,
+      bool is_alertable,
+      std::chrono::milliseconds timeout = std::chrono::milliseconds::max());
 };
 
 // Models a Win32-like event object.
@@ -118,7 +212,8 @@ class Semaphore : public WaitHandle {
   // decreased by one whenever a wait function releases a thread that was
   // waiting for the semaphore. The count is increased  by a specified amount by
   // calling the Release() function.
-  std::unique_ptr<Semaphore> Create(int initial_count, int maximum_count);
+  static std::unique_ptr<Semaphore> Create(int initial_count,
+                                           int maximum_count);
 
   // Increases the count of the specified semaphore object by a specified
   // amount.
@@ -134,7 +229,7 @@ class Mutant : public WaitHandle {
  public:
   // Creates a new mutant object, initially owned by the calling thread if
   // specified.
-  std::unique_ptr<Mutant> Create(bool initial_owner);
+  static std::unique_ptr<Mutant> Create(bool initial_owner);
 
   // Releases ownership of the specified mutex object.
   // Returns false if the calling thread does not own the mutant object.
@@ -145,11 +240,11 @@ class Timer : public WaitHandle {
  public:
   // Creates a timer whose state remains signaled until SetOnce() or
   // SetRepeating() is called to establish a new due time.
-  std::unique_ptr<Timer> CreateManualResetTimer();
+  static std::unique_ptr<Timer> CreateManualResetTimer();
 
   // Creates a timer whose state remains signaled until a thread completes a
   // wait operation on the timer object.
-  std::unique_ptr<Timer> CreateSynchronizationTimer();
+  static std::unique_ptr<Timer> CreateSynchronizationTimer();
 
   // Activates the specified waitable timer. When the due time arrives, the
   // timer is signaled and the thread that set the timer calls the optional

src/xenia/base/threading_win.cc

@@ -67,22 +67,98 @@ void Sleep(std::chrono::microseconds duration) {
   }
 }
 
-class Win32Handle {
+template <typename T>
+class Win32Handle : public T {
  public:
   Win32Handle(HANDLE handle) : handle_(handle) {}
-  virtual ~Win32Handle() {
+  ~Win32Handle() override {
     CloseHandle(handle_);
     handle_ = nullptr;
   }
 
  protected:
+  void* native_handle() const override { return handle_; }
+
   HANDLE handle_ = nullptr;
 };
 
-class Win32Event : public Event, public Win32Handle {
+WaitResult WaitHandle::Wait(WaitHandle* wait_handle, bool is_alertable,
+                            std::chrono::milliseconds timeout) {
+  HANDLE handle = wait_handle->native_handle();
+  DWORD result = WaitForSingleObjectEx(handle, DWORD(timeout.count()),
+                                       is_alertable ? TRUE : FALSE);
+  switch (result) {
+    case WAIT_OBJECT_0:
+      return WaitResult::kSuccess;
+    case WAIT_ABANDONED:
+      return WaitResult::kAbandoned;
+    case WAIT_IO_COMPLETION:
+      return WaitResult::kUserCallback;
+    case WAIT_TIMEOUT:
+      return WaitResult::kTimeout;
+    default:
+    case WAIT_FAILED:
+      return WaitResult::kFailed;
+  }
+}
+
+WaitResult WaitHandle::SignalAndWait(WaitHandle* wait_handle_to_signal,
+                                     WaitHandle* wait_handle_to_wait_on,
+                                     bool is_alertable,
+                                     std::chrono::milliseconds timeout) {
+  HANDLE handle_to_signal = wait_handle_to_signal->native_handle();
+  HANDLE handle_to_wait_on = wait_handle_to_wait_on->native_handle();
+  DWORD result =
+      SignalObjectAndWait(handle_to_signal, handle_to_wait_on,
+                          DWORD(timeout.count()), is_alertable ? TRUE : FALSE);
+  switch (result) {
+    case WAIT_OBJECT_0:
+      return WaitResult::kSuccess;
+    case WAIT_ABANDONED:
+      return WaitResult::kAbandoned;
+    case WAIT_IO_COMPLETION:
+      return WaitResult::kUserCallback;
+    case WAIT_TIMEOUT:
+      return WaitResult::kTimeout;
+    default:
+    case WAIT_FAILED:
+      return WaitResult::kFailed;
+  }
+}
+
+std::pair<WaitResult, size_t> WaitHandle::WaitMultiple(
+    WaitHandle* wait_handles[], size_t wait_handle_count, bool wait_all,
+    bool is_alertable, std::chrono::milliseconds timeout) {
+  std::vector<HANDLE> handles(wait_handle_count);
+  for (size_t i = 0; i < wait_handle_count; ++i) {
+    handles[i] = wait_handles[i]->native_handle();
+  }
+  DWORD result = WaitForMultipleObjectsEx(
+      DWORD(handles.size()), handles.data(), wait_all ? TRUE : FALSE,
+      DWORD(timeout.count()), is_alertable ? TRUE : FALSE);
+  if (result >= WAIT_OBJECT_0 && result < WAIT_OBJECT_0 + handles.size()) {
+    return std::pair<WaitResult, size_t>(WaitResult::kSuccess,
+                                         result - WAIT_OBJECT_0);
+  } else if (result >= WAIT_ABANDONED_0 &&
+             result < WAIT_ABANDONED_0 + handles.size()) {
+    return std::pair<WaitResult, size_t>(WaitResult::kAbandoned,
+                                         result - WAIT_ABANDONED_0);
+  }
+  switch (result) {
+    case WAIT_IO_COMPLETION:
+      return std::pair<WaitResult, size_t>(WaitResult::kUserCallback, 0);
+    case WAIT_TIMEOUT:
+      return std::pair<WaitResult, size_t>(WaitResult::kTimeout, 0);
+    default:
+    case WAIT_FAILED:
+      return std::pair<WaitResult, size_t>(WaitResult::kFailed, 0);
+  }
+}
+
+class Win32Event : public Win32Handle<Event> {
  public:
   Win32Event(HANDLE handle) : Win32Handle(handle) {}
-  ~Win32Event() = default;
+  ~Win32Event() override = default;
   void Set() override { SetEvent(handle_); }
   void Reset() override { ResetEvent(handle_); }
   void Pulse() override { PulseEvent(handle_); }
@@ -98,7 +174,7 @@ std::unique_ptr<Event> Event::CreateAutoResetEvent(bool initial_state) {
       CreateEvent(nullptr, FALSE, initial_state ? TRUE : FALSE, nullptr));
 }
 
-class Win32Semaphore : public Semaphore, public Win32Handle {
+class Win32Semaphore : public Win32Handle<Semaphore> {
  public:
   Win32Semaphore(HANDLE handle) : Win32Handle(handle) {}
   ~Win32Semaphore() override = default;
@@ -116,7 +192,7 @@ std::unique_ptr<Semaphore> Semaphore::Create(int initial_count,
       CreateSemaphore(nullptr, initial_count, maximum_count, nullptr));
 }
 
-class Win32Mutant : public Mutant, public Win32Handle {
+class Win32Mutant : public Win32Handle<Mutant> {
  public:
   Win32Mutant(HANDLE handle) : Win32Handle(handle) {}
   ~Win32Mutant() = default;
@@ -128,7 +204,7 @@ std::unique_ptr<Mutant> Mutant::Create(bool initial_owner) {
       CreateMutex(nullptr, initial_owner ? TRUE : FALSE, nullptr));
 }
 
-class Win32Timer : public Timer, public Win32Handle {
+class Win32Timer : public Win32Handle<Timer> {
  public:
   Win32Timer(HANDLE handle) : Win32Handle(handle) {}
   ~Win32Timer() = default;