Move everything into a separate futatabi/ subdir, for the upcoming merge with Futatabi.

[nageru] / nageru / ref_counted_frame.h

diff --git a/nageru/ref_counted_frame.h b/nageru/ref_counted_frame.h
new file mode 100644 (file)
index 0000000..59a1686
--- /dev/null
+++ b/nageru/ref_counted_frame.h
@@ -0,0 +1,60 @@
+#ifndef _REF_COUNTED_FRAME_H
+#define _REF_COUNTED_FRAME_H 1
+
+// A wrapper around FrameAllocator::Frame that is automatically refcounted;
+// when the refcount goes to zero, the frame is given back to the allocator.
+//
+// Note that the important point isn't really the pointer to the Frame itself,
+// it's the resources it's representing that need to go back to the allocator.
+//
+// FIXME: There's an issue here in that we could be releasing a frame while
+// we're still uploading textures from it, causing it to be written to in
+// another thread. (Thankfully, it goes to the back of the queue, and there's
+// usually a render in-between, meaning it's fairly unlikely that someone
+// actually managed to get to that race.) We should probably have some mechanism
+// for registering fences.
+
+#include <memory>
+
+#include "bmusb/bmusb.h"
+
+void release_refcounted_frame(bmusb::FrameAllocator::Frame *frame);
+
+typedef std::shared_ptr<bmusb::FrameAllocator::Frame> RefCountedFrameBase;
+
+class RefCountedFrame : public RefCountedFrameBase {
+public:
+       RefCountedFrame() {}
+
+       RefCountedFrame(const bmusb::FrameAllocator::Frame &frame)
+               : RefCountedFrameBase(new bmusb::FrameAllocator::Frame(frame), release_refcounted_frame) {}
+};
+
+// Similar to RefCountedFrame, but as unique_ptr instead of shared_ptr.
+
+struct Unique_frame_deleter {
+       void operator() (bmusb::FrameAllocator::Frame *frame) const {
+               release_refcounted_frame(frame);
+       }
+};
+
+typedef std::unique_ptr<bmusb::FrameAllocator::Frame, Unique_frame_deleter>
+       UniqueFrameBase;
+
+class UniqueFrame : public UniqueFrameBase {
+public:
+       UniqueFrame() {}
+
+       UniqueFrame(const bmusb::FrameAllocator::Frame &frame)
+               : UniqueFrameBase(new bmusb::FrameAllocator::Frame(frame)) {}
+
+       bmusb::FrameAllocator::Frame get_and_release()
+       {
+               bmusb::FrameAllocator::Frame *ptr = release();
+               bmusb::FrameAllocator::Frame frame = *ptr;
+               delete ptr;
+               return frame;
+       }
+};
+
+#endif  // !defined(_REF_COUNTED_FRAME_H)