Kernel: Move WaitObject to a separate file

Now that HandleTable doesn't directly depend on WaitObject anymore, this
can be separated from the main kernel.h header.

src/core/hle/kernel/wait_object.h

@@ -0,0 +1,67 @@
+// Copyright 2014 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <vector>
+#include <boost/smart_ptr/intrusive_ptr.hpp>
+#include "common/common_types.h"
+#include "core/hle/kernel/kernel.h"
+
+namespace Kernel {
+
+class Thread;
+
+/// Class that represents a Kernel object that a thread can be waiting on
+class WaitObject : public Object {
+public:
+    /**
+     * Check if the specified thread should wait until the object is available
+     * @param thread The thread about which we're deciding.
+     * @return True if the current thread should wait due to this object being unavailable
+     */
+    virtual bool ShouldWait(Thread* thread) const = 0;
+
+    /// Acquire/lock the object for the specified thread if it is available
+    virtual void Acquire(Thread* thread) = 0;
+
+    /**
+     * Add a thread to wait on this object
+     * @param thread Pointer to thread to add
+     */
+    virtual void AddWaitingThread(SharedPtr<Thread> thread);
+
+    /**
+     * Removes a thread from waiting on this object (e.g. if it was resumed already)
+     * @param thread Pointer to thread to remove
+     */
+    virtual void RemoveWaitingThread(Thread* thread);
+
+    /**
+     * Wake up all threads waiting on this object that can be awoken, in priority order,
+     * and set the synchronization result and output of the thread.
+     */
+    virtual void WakeupAllWaitingThreads();
+
+    /// Obtains the highest priority thread that is ready to run from this object's waiting list.
+    SharedPtr<Thread> GetHighestPriorityReadyThread();
+
+    /// Get a const reference to the waiting threads list for debug use
+    const std::vector<SharedPtr<Thread>>& GetWaitingThreads() const;
+
+private:
+    /// Threads waiting for this object to become available
+    std::vector<SharedPtr<Thread>> waiting_threads;
+};
+
+// Specialization of DynamicObjectCast for WaitObjects
+template <>
+inline SharedPtr<WaitObject> DynamicObjectCast<WaitObject>(SharedPtr<Object> object) {
+    if (object != nullptr && object->IsWaitable()) {
+        return boost::static_pointer_cast<WaitObject>(std::move(object));
+    }
+    return nullptr;
+}
+
+} // namespace Kernel