Files
garageDoorZigbee/venv/Lib/site-packages/serial/serialwin32.py
nathan wagner b96310f621 added in micropython external library for const feature.
it's returing valid attribute arrays, that just need converted on z2m
side.

it's also respecting the stop command from the console, which I will
attempt to expose as just a button press.
2022-04-24 12:44:08 -04:00

478 lines
20 KiB
Python

#! python
#
# backend for Windows ("win32" incl. 32/64 bit support)
#
# (C) 2001-2020 Chris Liechti <cliechti@gmx.net>
#
# This file is part of pySerial. https://github.com/pyserial/pyserial
# SPDX-License-Identifier: BSD-3-Clause
#
# Initial patch to use ctypes by Giovanni Bajo <rasky@develer.com>
from __future__ import absolute_import
# pylint: disable=invalid-name,too-few-public-methods
import ctypes
import time
from serial import win32
import serial
from serial.serialutil import SerialBase, SerialException, to_bytes, PortNotOpenError, SerialTimeoutException
class Serial(SerialBase):
"""Serial port implementation for Win32 based on ctypes."""
BAUDRATES = (50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800,
9600, 19200, 38400, 57600, 115200)
def __init__(self, *args, **kwargs):
self._port_handle = None
self._overlapped_read = None
self._overlapped_write = None
super(Serial, self).__init__(*args, **kwargs)
def open(self):
"""\
Open port with current settings. This may throw a SerialException
if the port cannot be opened.
"""
if self._port is None:
raise SerialException("Port must be configured before it can be used.")
if self.is_open:
raise SerialException("Port is already open.")
# the "\\.\COMx" format is required for devices other than COM1-COM8
# not all versions of windows seem to support this properly
# so that the first few ports are used with the DOS device name
port = self.name
try:
if port.upper().startswith('COM') and int(port[3:]) > 8:
port = '\\\\.\\' + port
except ValueError:
# for like COMnotanumber
pass
self._port_handle = win32.CreateFile(
port,
win32.GENERIC_READ | win32.GENERIC_WRITE,
0, # exclusive access
None, # no security
win32.OPEN_EXISTING,
win32.FILE_ATTRIBUTE_NORMAL | win32.FILE_FLAG_OVERLAPPED,
0)
if self._port_handle == win32.INVALID_HANDLE_VALUE:
self._port_handle = None # 'cause __del__ is called anyway
raise SerialException("could not open port {!r}: {!r}".format(self.portstr, ctypes.WinError()))
try:
self._overlapped_read = win32.OVERLAPPED()
self._overlapped_read.hEvent = win32.CreateEvent(None, 1, 0, None)
self._overlapped_write = win32.OVERLAPPED()
#~ self._overlapped_write.hEvent = win32.CreateEvent(None, 1, 0, None)
self._overlapped_write.hEvent = win32.CreateEvent(None, 0, 0, None)
# Setup a 4k buffer
win32.SetupComm(self._port_handle, 4096, 4096)
# Save original timeout values:
self._orgTimeouts = win32.COMMTIMEOUTS()
win32.GetCommTimeouts(self._port_handle, ctypes.byref(self._orgTimeouts))
self._reconfigure_port()
# Clear buffers:
# Remove anything that was there
win32.PurgeComm(
self._port_handle,
win32.PURGE_TXCLEAR | win32.PURGE_TXABORT |
win32.PURGE_RXCLEAR | win32.PURGE_RXABORT)
except:
try:
self._close()
except:
# ignore any exception when closing the port
# also to keep original exception that happened when setting up
pass
self._port_handle = None
raise
else:
self.is_open = True
def _reconfigure_port(self):
"""Set communication parameters on opened port."""
if not self._port_handle:
raise SerialException("Can only operate on a valid port handle")
# Set Windows timeout values
# timeouts is a tuple with the following items:
# (ReadIntervalTimeout,ReadTotalTimeoutMultiplier,
# ReadTotalTimeoutConstant,WriteTotalTimeoutMultiplier,
# WriteTotalTimeoutConstant)
timeouts = win32.COMMTIMEOUTS()
if self._timeout is None:
pass # default of all zeros is OK
elif self._timeout == 0:
timeouts.ReadIntervalTimeout = win32.MAXDWORD
else:
timeouts.ReadTotalTimeoutConstant = max(int(self._timeout * 1000), 1)
if self._timeout != 0 and self._inter_byte_timeout is not None:
timeouts.ReadIntervalTimeout = max(int(self._inter_byte_timeout * 1000), 1)
if self._write_timeout is None:
pass
elif self._write_timeout == 0:
timeouts.WriteTotalTimeoutConstant = win32.MAXDWORD
else:
timeouts.WriteTotalTimeoutConstant = max(int(self._write_timeout * 1000), 1)
win32.SetCommTimeouts(self._port_handle, ctypes.byref(timeouts))
win32.SetCommMask(self._port_handle, win32.EV_ERR)
# Setup the connection info.
# Get state and modify it:
comDCB = win32.DCB()
win32.GetCommState(self._port_handle, ctypes.byref(comDCB))
comDCB.BaudRate = self._baudrate
if self._bytesize == serial.FIVEBITS:
comDCB.ByteSize = 5
elif self._bytesize == serial.SIXBITS:
comDCB.ByteSize = 6
elif self._bytesize == serial.SEVENBITS:
comDCB.ByteSize = 7
elif self._bytesize == serial.EIGHTBITS:
comDCB.ByteSize = 8
else:
raise ValueError("Unsupported number of data bits: {!r}".format(self._bytesize))
if self._parity == serial.PARITY_NONE:
comDCB.Parity = win32.NOPARITY
comDCB.fParity = 0 # Disable Parity Check
elif self._parity == serial.PARITY_EVEN:
comDCB.Parity = win32.EVENPARITY
comDCB.fParity = 1 # Enable Parity Check
elif self._parity == serial.PARITY_ODD:
comDCB.Parity = win32.ODDPARITY
comDCB.fParity = 1 # Enable Parity Check
elif self._parity == serial.PARITY_MARK:
comDCB.Parity = win32.MARKPARITY
comDCB.fParity = 1 # Enable Parity Check
elif self._parity == serial.PARITY_SPACE:
comDCB.Parity = win32.SPACEPARITY
comDCB.fParity = 1 # Enable Parity Check
else:
raise ValueError("Unsupported parity mode: {!r}".format(self._parity))
if self._stopbits == serial.STOPBITS_ONE:
comDCB.StopBits = win32.ONESTOPBIT
elif self._stopbits == serial.STOPBITS_ONE_POINT_FIVE:
comDCB.StopBits = win32.ONE5STOPBITS
elif self._stopbits == serial.STOPBITS_TWO:
comDCB.StopBits = win32.TWOSTOPBITS
else:
raise ValueError("Unsupported number of stop bits: {!r}".format(self._stopbits))
comDCB.fBinary = 1 # Enable Binary Transmission
# Char. w/ Parity-Err are replaced with 0xff (if fErrorChar is set to TRUE)
if self._rs485_mode is None:
if self._rtscts:
comDCB.fRtsControl = win32.RTS_CONTROL_HANDSHAKE
else:
comDCB.fRtsControl = win32.RTS_CONTROL_ENABLE if self._rts_state else win32.RTS_CONTROL_DISABLE
comDCB.fOutxCtsFlow = self._rtscts
else:
# checks for unsupported settings
# XXX verify if platform really does not have a setting for those
if not self._rs485_mode.rts_level_for_tx:
raise ValueError(
'Unsupported value for RS485Settings.rts_level_for_tx: {!r} (only True is allowed)'.format(
self._rs485_mode.rts_level_for_tx,))
if self._rs485_mode.rts_level_for_rx:
raise ValueError(
'Unsupported value for RS485Settings.rts_level_for_rx: {!r} (only False is allowed)'.format(
self._rs485_mode.rts_level_for_rx,))
if self._rs485_mode.delay_before_tx is not None:
raise ValueError(
'Unsupported value for RS485Settings.delay_before_tx: {!r} (only None is allowed)'.format(
self._rs485_mode.delay_before_tx,))
if self._rs485_mode.delay_before_rx is not None:
raise ValueError(
'Unsupported value for RS485Settings.delay_before_rx: {!r} (only None is allowed)'.format(
self._rs485_mode.delay_before_rx,))
if self._rs485_mode.loopback:
raise ValueError(
'Unsupported value for RS485Settings.loopback: {!r} (only False is allowed)'.format(
self._rs485_mode.loopback,))
comDCB.fRtsControl = win32.RTS_CONTROL_TOGGLE
comDCB.fOutxCtsFlow = 0
if self._dsrdtr:
comDCB.fDtrControl = win32.DTR_CONTROL_HANDSHAKE
else:
comDCB.fDtrControl = win32.DTR_CONTROL_ENABLE if self._dtr_state else win32.DTR_CONTROL_DISABLE
comDCB.fOutxDsrFlow = self._dsrdtr
comDCB.fOutX = self._xonxoff
comDCB.fInX = self._xonxoff
comDCB.fNull = 0
comDCB.fErrorChar = 0
comDCB.fAbortOnError = 0
comDCB.XonChar = serial.XON
comDCB.XoffChar = serial.XOFF
if not win32.SetCommState(self._port_handle, ctypes.byref(comDCB)):
raise SerialException(
'Cannot configure port, something went wrong. '
'Original message: {!r}'.format(ctypes.WinError()))
#~ def __del__(self):
#~ self.close()
def _close(self):
"""internal close port helper"""
if self._port_handle is not None:
# Restore original timeout values:
win32.SetCommTimeouts(self._port_handle, self._orgTimeouts)
if self._overlapped_read is not None:
self.cancel_read()
win32.CloseHandle(self._overlapped_read.hEvent)
self._overlapped_read = None
if self._overlapped_write is not None:
self.cancel_write()
win32.CloseHandle(self._overlapped_write.hEvent)
self._overlapped_write = None
win32.CloseHandle(self._port_handle)
self._port_handle = None
def close(self):
"""Close port"""
if self.is_open:
self._close()
self.is_open = False
# - - - - - - - - - - - - - - - - - - - - - - - -
@property
def in_waiting(self):
"""Return the number of bytes currently in the input buffer."""
flags = win32.DWORD()
comstat = win32.COMSTAT()
if not win32.ClearCommError(self._port_handle, ctypes.byref(flags), ctypes.byref(comstat)):
raise SerialException("ClearCommError failed ({!r})".format(ctypes.WinError()))
return comstat.cbInQue
def read(self, size=1):
"""\
Read size bytes from the serial port. If a timeout is set it may
return less characters as requested. With no timeout it will block
until the requested number of bytes is read.
"""
if not self.is_open:
raise PortNotOpenError()
if size > 0:
win32.ResetEvent(self._overlapped_read.hEvent)
flags = win32.DWORD()
comstat = win32.COMSTAT()
if not win32.ClearCommError(self._port_handle, ctypes.byref(flags), ctypes.byref(comstat)):
raise SerialException("ClearCommError failed ({!r})".format(ctypes.WinError()))
n = min(comstat.cbInQue, size) if self.timeout == 0 else size
if n > 0:
buf = ctypes.create_string_buffer(n)
rc = win32.DWORD()
read_ok = win32.ReadFile(
self._port_handle,
buf,
n,
ctypes.byref(rc),
ctypes.byref(self._overlapped_read))
if not read_ok and win32.GetLastError() not in (win32.ERROR_SUCCESS, win32.ERROR_IO_PENDING):
raise SerialException("ReadFile failed ({!r})".format(ctypes.WinError()))
result_ok = win32.GetOverlappedResult(
self._port_handle,
ctypes.byref(self._overlapped_read),
ctypes.byref(rc),
True)
if not result_ok:
if win32.GetLastError() != win32.ERROR_OPERATION_ABORTED:
raise SerialException("GetOverlappedResult failed ({!r})".format(ctypes.WinError()))
read = buf.raw[:rc.value]
else:
read = bytes()
else:
read = bytes()
return bytes(read)
def write(self, data):
"""Output the given byte string over the serial port."""
if not self.is_open:
raise PortNotOpenError()
#~ if not isinstance(data, (bytes, bytearray)):
#~ raise TypeError('expected %s or bytearray, got %s' % (bytes, type(data)))
# convert data (needed in case of memoryview instance: Py 3.1 io lib), ctypes doesn't like memoryview
data = to_bytes(data)
if data:
#~ win32event.ResetEvent(self._overlapped_write.hEvent)
n = win32.DWORD()
success = win32.WriteFile(self._port_handle, data, len(data), ctypes.byref(n), self._overlapped_write)
if self._write_timeout != 0: # if blocking (None) or w/ write timeout (>0)
if not success and win32.GetLastError() not in (win32.ERROR_SUCCESS, win32.ERROR_IO_PENDING):
raise SerialException("WriteFile failed ({!r})".format(ctypes.WinError()))
# Wait for the write to complete.
#~ win32.WaitForSingleObject(self._overlapped_write.hEvent, win32.INFINITE)
win32.GetOverlappedResult(self._port_handle, self._overlapped_write, ctypes.byref(n), True)
if win32.GetLastError() == win32.ERROR_OPERATION_ABORTED:
return n.value # canceled IO is no error
if n.value != len(data):
raise SerialTimeoutException('Write timeout')
return n.value
else:
errorcode = win32.ERROR_SUCCESS if success else win32.GetLastError()
if errorcode in (win32.ERROR_INVALID_USER_BUFFER, win32.ERROR_NOT_ENOUGH_MEMORY,
win32.ERROR_OPERATION_ABORTED):
return 0
elif errorcode in (win32.ERROR_SUCCESS, win32.ERROR_IO_PENDING):
# no info on true length provided by OS function in async mode
return len(data)
else:
raise SerialException("WriteFile failed ({!r})".format(ctypes.WinError()))
else:
return 0
def flush(self):
"""\
Flush of file like objects. In this case, wait until all data
is written.
"""
while self.out_waiting:
time.sleep(0.05)
# XXX could also use WaitCommEvent with mask EV_TXEMPTY, but it would
# require overlapped IO and it's also only possible to set a single mask
# on the port---
def reset_input_buffer(self):
"""Clear input buffer, discarding all that is in the buffer."""
if not self.is_open:
raise PortNotOpenError()
win32.PurgeComm(self._port_handle, win32.PURGE_RXCLEAR | win32.PURGE_RXABORT)
def reset_output_buffer(self):
"""\
Clear output buffer, aborting the current output and discarding all
that is in the buffer.
"""
if not self.is_open:
raise PortNotOpenError()
win32.PurgeComm(self._port_handle, win32.PURGE_TXCLEAR | win32.PURGE_TXABORT)
def _update_break_state(self):
"""Set break: Controls TXD. When active, to transmitting is possible."""
if not self.is_open:
raise PortNotOpenError()
if self._break_state:
win32.SetCommBreak(self._port_handle)
else:
win32.ClearCommBreak(self._port_handle)
def _update_rts_state(self):
"""Set terminal status line: Request To Send"""
if self._rts_state:
win32.EscapeCommFunction(self._port_handle, win32.SETRTS)
else:
win32.EscapeCommFunction(self._port_handle, win32.CLRRTS)
def _update_dtr_state(self):
"""Set terminal status line: Data Terminal Ready"""
if self._dtr_state:
win32.EscapeCommFunction(self._port_handle, win32.SETDTR)
else:
win32.EscapeCommFunction(self._port_handle, win32.CLRDTR)
def _GetCommModemStatus(self):
if not self.is_open:
raise PortNotOpenError()
stat = win32.DWORD()
win32.GetCommModemStatus(self._port_handle, ctypes.byref(stat))
return stat.value
@property
def cts(self):
"""Read terminal status line: Clear To Send"""
return win32.MS_CTS_ON & self._GetCommModemStatus() != 0
@property
def dsr(self):
"""Read terminal status line: Data Set Ready"""
return win32.MS_DSR_ON & self._GetCommModemStatus() != 0
@property
def ri(self):
"""Read terminal status line: Ring Indicator"""
return win32.MS_RING_ON & self._GetCommModemStatus() != 0
@property
def cd(self):
"""Read terminal status line: Carrier Detect"""
return win32.MS_RLSD_ON & self._GetCommModemStatus() != 0
# - - platform specific - - - -
def set_buffer_size(self, rx_size=4096, tx_size=None):
"""\
Recommend a buffer size to the driver (device driver can ignore this
value). Must be called after the port is opened.
"""
if tx_size is None:
tx_size = rx_size
win32.SetupComm(self._port_handle, rx_size, tx_size)
def set_output_flow_control(self, enable=True):
"""\
Manually control flow - when software flow control is enabled.
This will do the same as if XON (true) or XOFF (false) are received
from the other device and control the transmission accordingly.
WARNING: this function is not portable to different platforms!
"""
if not self.is_open:
raise PortNotOpenError()
if enable:
win32.EscapeCommFunction(self._port_handle, win32.SETXON)
else:
win32.EscapeCommFunction(self._port_handle, win32.SETXOFF)
@property
def out_waiting(self):
"""Return how many bytes the in the outgoing buffer"""
flags = win32.DWORD()
comstat = win32.COMSTAT()
if not win32.ClearCommError(self._port_handle, ctypes.byref(flags), ctypes.byref(comstat)):
raise SerialException("ClearCommError failed ({!r})".format(ctypes.WinError()))
return comstat.cbOutQue
def _cancel_overlapped_io(self, overlapped):
"""Cancel a blocking read operation, may be called from other thread"""
# check if read operation is pending
rc = win32.DWORD()
err = win32.GetOverlappedResult(
self._port_handle,
ctypes.byref(overlapped),
ctypes.byref(rc),
False)
if not err and win32.GetLastError() in (win32.ERROR_IO_PENDING, win32.ERROR_IO_INCOMPLETE):
# cancel, ignoring any errors (e.g. it may just have finished on its own)
win32.CancelIoEx(self._port_handle, overlapped)
def cancel_read(self):
"""Cancel a blocking read operation, may be called from other thread"""
self._cancel_overlapped_io(self._overlapped_read)
def cancel_write(self):
"""Cancel a blocking write operation, may be called from other thread"""
self._cancel_overlapped_io(self._overlapped_write)
@SerialBase.exclusive.setter
def exclusive(self, exclusive):
"""Change the exclusive access setting."""
if exclusive is not None and not exclusive:
raise ValueError('win32 only supports exclusive access (not: {})'.format(exclusive))
else:
serial.SerialBase.exclusive.__set__(self, exclusive)