1 #ifndef ANDROID_DVR_SERVICES_DISPLAYD_DISPLAY_SURFACE_H_
2 #define ANDROID_DVR_SERVICES_DISPLAYD_DISPLAY_SURFACE_H_
3 
4 #include <pdx/file_handle.h>
5 #include <pdx/service.h>
6 #include <private/dvr/buffer_hub_queue_client.h>
7 #include <private/dvr/display_protocol.h>
8 #include <private/dvr/ring_buffer.h>
9 
10 #include <functional>
11 #include <iterator>
12 #include <memory>
13 #include <string>
14 #include <vector>
15 
16 #include "acquired_buffer.h"
17 
18 namespace android {
19 namespace dvr {
20 
21 class DisplayService;
22 
23 enum class SurfaceType {
24   Direct,
25   Application,
26 };
27 
28 class DisplaySurface : public pdx::Channel {
29  public:
30   static pdx::Status<std::shared_ptr<DisplaySurface>> Create(
31       DisplayService* service, int surface_id, int process_id, int user_id,
32       const display::SurfaceAttributes& attributes);
33 
34   ~DisplaySurface() override;
35 
service()36   DisplayService* service() const { return service_; }
surface_type()37   SurfaceType surface_type() const { return surface_type_; }
surface_id()38   int surface_id() const { return surface_id_; }
process_id()39   int process_id() const { return process_id_; }
user_id()40   int user_id() const { return user_id_; }
41 
visible()42   bool visible() const { return visible_; }
z_order()43   int z_order() const { return z_order_; }
44 
attributes()45   const display::SurfaceAttributes& attributes() const { return attributes_; }
update_flags()46   display::SurfaceUpdateFlags update_flags() const { return update_flags_; }
47 
GetQueueIds()48   virtual std::vector<int32_t> GetQueueIds() const { return {}; }
49 
IsUpdatePending()50   bool IsUpdatePending() const {
51     return update_flags_.value() != display::SurfaceUpdateFlags::None;
52   }
53 
54  protected:
55   DisplaySurface(DisplayService* service, SurfaceType surface_type,
56                  int surface_id, int process_id, int user_id,
57                  const display::SurfaceAttributes& attributes);
58 
59   // Utility to retrieve a shared pointer to this channel as the desired derived
60   // type.
61   template <
62       typename T = DisplaySurface,
63       typename = std::enable_if_t<std::is_base_of<DisplaySurface, T>::value>>
Self()64   std::shared_ptr<T> Self() {
65     return std::static_pointer_cast<T>(shared_from_this());
66   }
67 
68   virtual pdx::Status<pdx::LocalChannelHandle> OnCreateQueue(
69       pdx::Message& message, size_t meta_size_bytes) = 0;
70 
71   // Registers a consumer queue with the event dispatcher in DisplayService. The
72   // OnQueueEvent callback below is called to handle queue events.
73   pdx::Status<void> RegisterQueue(
74       const std::shared_ptr<ConsumerQueue>& consumer_queue);
75   pdx::Status<void> UnregisterQueue(
76       const std::shared_ptr<ConsumerQueue>& consumer_queue);
77 
78   // Called by the event dispatcher in DisplayService when a registered queue
79   // event triggers. Executes on the event dispatcher thread.
80   virtual void OnQueueEvent(
81       const std::shared_ptr<ConsumerQueue>& consumer_queue, int events);
82 
83   void SurfaceUpdated(display::SurfaceUpdateFlags update_flags);
84   void ClearUpdate();
85 
86   // Synchronizes access to mutable state below between message dispatch thread
87   // and frame post thread.
88   mutable std::mutex lock_;
89 
90  private:
91   friend class DisplayService;
92   friend class DisplayManagerService;
93 
94   // Dispatches display surface messages to the appropriate handlers. This
95   // handler runs on the VrFlinger message dispatch thread.
96   pdx::Status<void> HandleMessage(pdx::Message& message);
97 
98   pdx::Status<void> OnSetAttributes(
99       pdx::Message& message, const display::SurfaceAttributes& attributes);
100   pdx::Status<display::SurfaceInfo> OnGetSurfaceInfo(pdx::Message& message);
101 
102   DisplayService* service_;
103   SurfaceType surface_type_;
104   int surface_id_;
105   int process_id_;
106   int user_id_;
107 
108   display::SurfaceAttributes attributes_;
109   display::SurfaceUpdateFlags update_flags_ = display::SurfaceUpdateFlags::None;
110 
111   // Subset of attributes that may be interpreted by the display service.
112   bool visible_ = false;
113   int z_order_ = 0;
114 
115   DisplaySurface(const DisplaySurface&) = delete;
116   void operator=(const DisplaySurface&) = delete;
117 };
118 
119 class ApplicationDisplaySurface : public DisplaySurface {
120  public:
ApplicationDisplaySurface(DisplayService * service,int surface_id,int process_id,int user_id,const display::SurfaceAttributes & attributes)121   ApplicationDisplaySurface(DisplayService* service, int surface_id,
122                             int process_id, int user_id,
123                             const display::SurfaceAttributes& attributes)
124       : DisplaySurface(service, SurfaceType::Application, surface_id,
125                        process_id, user_id, attributes) {}
126 
127   std::shared_ptr<ConsumerQueue> GetQueue(int32_t queue_id);
128   std::vector<int32_t> GetQueueIds() const override;
129 
130  private:
131   pdx::Status<pdx::LocalChannelHandle> OnCreateQueue(
132       pdx::Message& message, size_t meta_size_bytes) override;
133   void OnQueueEvent(const std::shared_ptr<ConsumerQueue>& consumer_queue,
134                     int events) override;
135 
136   std::unordered_map<int32_t, std::shared_ptr<ConsumerQueue>> consumer_queues_;
137 };
138 
139 class DirectDisplaySurface : public DisplaySurface {
140  public:
DirectDisplaySurface(DisplayService * service,int surface_id,int process_id,int user_id,const display::SurfaceAttributes & attributes)141   DirectDisplaySurface(DisplayService* service, int surface_id, int process_id,
142                        int user_id,
143                        const display::SurfaceAttributes& attributes)
144       : DisplaySurface(service, SurfaceType::Direct, surface_id, process_id,
145                        user_id, attributes),
146         acquired_buffers_(kMaxPostedBuffers) {}
147   bool IsBufferAvailable();
148   bool IsBufferPosted();
149   AcquiredBuffer AcquireCurrentBuffer();
150 
151   // Get the newest buffer. Up to one buffer will be skipped. If a buffer is
152   // skipped, it will be stored in skipped_buffer if non null.
153   AcquiredBuffer AcquireNewestAvailableBuffer(AcquiredBuffer* skipped_buffer);
154 
155  private:
156   pdx::Status<pdx::LocalChannelHandle> OnCreateQueue(
157       pdx::Message& message, size_t meta_size_bytes) override;
158   void OnQueueEvent(const std::shared_ptr<ConsumerQueue>& consumer_queue,
159                     int events) override;
160 
161   // The capacity of the pending buffer queue. Should be enough to hold all the
162   // buffers of this DisplaySurface, although in practice only 1 or 2 frames
163   // will be pending at a time.
164   static constexpr int kSurfaceBufferMaxCount = 4;
165   static constexpr int kSurfaceViewMaxCount = 4;
166   static constexpr int kMaxPostedBuffers =
167       kSurfaceBufferMaxCount * kSurfaceViewMaxCount;
168 
169   // Returns whether a frame is available without locking the mutex.
170   bool IsFrameAvailableNoLock() const;
171 
172   // Dequeue all available buffers from the consumer queue.
173   void DequeueBuffersLocked();
174 
175   // In a triple-buffered surface, up to kMaxPostedBuffers buffers may be
176   // posted and pending.
177   RingBuffer<AcquiredBuffer> acquired_buffers_;
178 
179   std::shared_ptr<ConsumerQueue> direct_queue_;
180 };
181 
182 }  // namespace dvr
183 }  // namespace android
184 
185 #endif  // ANDROID_DVR_SERVICES_DISPLAYD_DISPLAY_SURFACE_H_
186