Merge 2ba7a4c into c29fa56

krzysz00 · web-flow · commit aff0999b2ba5 · 2022-02-11T14:00:20.000+10:00
diff --git a/source/brailleDisplayDrivers/freedomScientific.py b/source/brailleDisplayDrivers/freedomScientific.py
@@ -208,7 +208,8 @@ def __init__(self, port="auto"):
 						epIn=1,
 						epOut=0,
 						onReceive=self._onReceive,
-						onReceiveSize=56
+						onReceiveSize=56,
+						onReadError=self._handleReadError
 					)
 				else:
 					self._dev = hwIo.Serial(
@@ -245,6 +246,7 @@ def __init__(self, port="auto"):
 			"globalCommands", "GlobalCommands", "braille_scrollBack")
 		self.gestureMap.add("br(freedomScientific):topRouting%d" % self.numCells,
 			"globalCommands", "GlobalCommands", "braille_scrollForward")
+		self._restarting = False
 
 	def terminate(self):
 		try:
@@ -317,6 +319,17 @@ def _onReceive(self, data: bytes):
 
 		self._handlePacket(packetType, arg1, arg2, arg3, payload)
 
+	def _handleReadError(self, error: int) -> bool:
+		if error == 995:  # Broken I/O pipe, terminate and allow restart
+			if not self._restarting:
+				# Will not cause a data race since this driver runs on one thread
+				self._restarting = True
+				log.info("Freedom Scientific display implicitly disconnected by suspend, reinitializing")
+				self.terminate()
+				self.__init__()
+			return True
+		return False
+
 	def _handlePacket(
 			self, packetType: bytes, arg1: bytes, arg2: bytes, arg3: bytes, payload: bytes
 	):
diff --git a/source/hwIo/base.py b/source/hwIo/base.py
@@ -39,7 +39,8 @@ def __init__(
 			fileHandle: Union[ctypes.wintypes.HANDLE],
 			onReceive: Callable[[bytes], None],
 			writeFileHandle: Optional[ctypes.wintypes.HANDLE] = None,
-			onReceiveSize: int = 1
+			onReceiveSize: int = 1,
+			onReadError: Optional[Callable[[int], bool]] = None
 	):
 		"""Constructor.
 		@param fileHandle: A handle to an open I/O device opened for overlapped I/O.
@@ -48,11 +49,15 @@ def __init__(
 		@param onReceive: A callable taking the received data as its only argument.
 		@param writeFileHandle: A handle to an open output device opened for overlapped I/O.
 		@param onReceiveSize: The size (in bytes) of the data with which to call C{onReceive}.
+		@param onReadError: If provided, a callback that takes the error code for a failed read
+		  and returns True if the I/O loop should exit cleanly or False if an
+		  exception should be thrown
 		"""
 		self._file = fileHandle
 		self._onReceive = onReceive
 		self._writeFile = writeFileHandle if writeFileHandle is not None else fileHandle
 		self._readSize = onReceiveSize
+		self._onReadError = onReadError
 		self._readBuf = ctypes.create_string_buffer(onReceiveSize)
 		self._readOl = OVERLAPPED()
 		self._recvEvt = winKernel.createEvent()
@@ -141,7 +146,11 @@ def _ioDone(self, error, numberOfBytes: int, overlapped):
 			self._ioDone = None
 			return
 		elif error != 0:
-			raise ctypes.WinError(error)
+			if not self._onReadError or not self._onReadError(error):
+				raise ctypes.WinError(error)
+			else:
+				self._ioDone = None
+				return
 		self._notifyReceive(self._readBuf[:numberOfBytes])
 		winKernel.kernel32.SetEvent(self._recvEvt)
 		self._asyncRead()
@@ -244,13 +253,17 @@ class Bulk(IoBase):
 	def __init__(
 			self, path: str, epIn: int, epOut: int,
 			onReceive: Callable[[bytes], None],
-			onReceiveSize: int = 1
+			onReceiveSize: int = 1,
+			onReadError: Optional[Callable[[int], bool]] = None
 	):
 		"""Constructor.
 		@param path: The device path.
 		@param epIn: The endpoint to read data from.
 		@param epOut: The endpoint to write data to.
 		@param onReceive: A callable taking a received input report as its only argument.
+		@param onReadError: An optional callable that handles read errors.
+		  It takes an error code and returns True if the error has been handled,
+		  allowing the read loop to exit cleanly, or False if an exception should be thrown.
 		"""
 		if _isDebug():
 			log.debug("Opening device %s" % path)
@@ -269,7 +282,8 @@ def __init__(
 				log.debug("Open write handle failed: %s" % ctypes.WinError())
 			raise ctypes.WinError()
 		super(Bulk, self).__init__(readHandle, onReceive,
-			writeFileHandle=writeHandle, onReceiveSize=onReceiveSize)
+		                           writeFileHandle=writeHandle, onReceiveSize=onReceiveSize,
+		                           onReadError=onReadError)
 
 	def close(self):
 		super(Bulk, self).close()
diff --git a/user_docs/en/changes.t2t b/user_docs/en/changes.t2t
@@ -55,6 +55,7 @@ What's New in NVDA
 - Windows 11 Mail: After switching focus between apps, while reading a long email, NVDA would get stuck on a line of the email. (#13050)
 - HID braille: chorded gestures (E.g. space+dot4) can be successfully performed from the Braille display. (#13326)
 - Fixed an issue where multiple settings dialogs could be opened at the same time. (#12818)
+- Fixed a problem where some Focus Blue Braille displays would stop working after waking the computer from sleep. (#9830)
 -
 
 == Changes for Developers ==

Original file line number	Diff line number	Diff line change
`@@ -55,6 +55,7 @@ What's New in NVDA`
`55`	`55`	`- Windows 11 Mail: After switching focus between apps, while reading a long email, NVDA would get stuck on a line of the email. (#13050)`
`56`	`56`	`- HID braille: chorded gestures (E.g. space+dot4) can be successfully performed from the Braille display. (#13326)`
`57`	`57`	`- Fixed an issue where multiple settings dialogs could be opened at the same time. (#12818)`
	`58`	`+- Fixed a problem where some Focus Blue Braille displays would stop working after waking the computer from sleep. (#9830)`
`58`	`59`	`-`
`59`	`60`
`60`	`61`	`== Changes for Developers ==`