commit b76af93ab56bc3296e01e65a6fe64a0622ab5b91
author Jerry Zhang <zhangjerry@google.com> Tue May 22 12:08:35 2018 -0700
committer Hridya Valsaraju <hridya@google.com> Mon Jul 30 20:17:27 2018 +0000
tree 72a598a84fa4bb141873c59ec979e9660e1c2428
parent 6f1f2c811acba2b2b7b5dc965c5cba350c30d039

recovery: Add ability to interrupt UI

Normally calling a UI method will block
indefinitely until the UI is actually
used. This creates a method to interrupt
the UI, causing waitKey to return -2. This
in turn, will cause ShowMenu to return -2.
This allows switching between recovery and
fastbootd via usb commands.

Test: adb shell /data/nativetest64/recovery_unit_test/recovery_unit_test
Bug: 78793464
Change-Id: I4c6c9aa18d79070877841a5c9818acf723fa6096

ui.h

diff --git a/ui.h b/ui.h
index 32e2809..a1e18cc 100644
--- a/ui.h
+++ b/ui.h
@@ -51,6 +51,11 @@
     IGNORE
   };
 
+  enum class KeyError : int {
+    TIMED_OUT = -1,
+    INTERRUPTED = -2,
+  };
+
   RecoveryUI();
 
   virtual ~RecoveryUI();
@@ -99,9 +104,13 @@
 
   // --- key handling ---
 
-  // Waits for a key and return it. May return -1 after timeout.
+  // Waits for a key and return it. May return TIMED_OUT after timeout and
+  // KeyError::INTERRUPTED on a key interrupt.
   virtual int WaitKey();
 
+  // Wakes up the UI if it is waiting on key input, causing WaitKey to return KeyError::INTERRUPTED.
+  virtual void InterruptKey();
+
   virtual bool IsKeyPressed(int key);
   virtual bool IsLongPress();
 
@@ -147,11 +156,22 @@
   // device-specific action, even without that being listed in the menu. Caller needs to handle
   // such a case accordingly (e.g. by calling Device::InvokeMenuItem() to process the action).
   // Returns a non-negative value (the chosen item number or device-specific action code), or
-  // static_cast<size_t>(-1) if timed out waiting for input.
+  // static_cast<size_t>(TIMED_OUT) if timed out waiting for input or
+  // static_cast<size_t>(ERR_KEY_INTERTUPT) if interrupted, such as by InterruptKey().
   virtual size_t ShowMenu(const std::vector<std::string>& headers,
                           const std::vector<std::string>& items, size_t initial_selection,
                           bool menu_only, const std::function<int(int, bool)>& key_handler) = 0;
 
+  // Resets the key interrupt status.
+  void ResetKeyInterruptStatus() {
+    key_interrupted_ = false;
+  }
+
+  // Returns the key interrupt status.
+  bool IsKeyInterrupted() const {
+    return key_interrupted_;
+  }
+
  protected:
   void EnqueueKey(int key_code);
 
@@ -187,10 +207,11 @@
   bool IsUsbConnected();
 
   bool InitScreensaver();
-
+  void SetScreensaverState(ScreensaverState state);
   // Key event input queue
   std::mutex key_queue_mutex;
   std::condition_variable key_queue_cond;
+  bool key_interrupted_;
   int key_queue[256], key_queue_len;
   char key_pressed[KEY_MAX + 1];  // under key_queue_mutex
   int key_last_down;              // under key_queue_mutex