def write(self, data):
"""Output the given byte string over the serial port."""
if not self.is_open:
raise portNotOpenError
d = to_bytes(data)
tx_len = length = len(d)
timeout = Timeout(self._write_timeout)
while tx_len > 0:
try:
n = os.write(self.fd, d)
if timeout.is_non_blocking:
# Zero timeout indicates non-blocking - simply return the
# number of bytes of data actually written
return n
elif not timeout.is_infinite:
# when timeout is set, use select to wait for being ready
# with the time left as timeout
if timeout.expired():
raise writeTimeoutError
abort, ready, _ = select.select([self.pipe_abort_write_r],
[self.fd], [],
timeout.time_left())
if abort:
os.read(self.pipe_abort_write_r, 1000)
break
if not ready:
raise writeTimeoutError
else:
assert timeout.time_left() is None
# wait for write operation
abort, ready, _ = select.select([self.pipe_abort_write_r],
[self.fd], [], None)
if abort:
os.read(self.pipe_abort_write_r, 1)
break
if not ready:
raise SerialException('write failed (select)')
d = d[n:]
tx_len -= n
except SerialException:
raise
except OSError as e:
# this is for Python 3.x where select.error is a subclass of
# OSError ignore BlockingIOErrors and EINTR. other errors are shown
# https://www.python.org/dev/peps/pep-0475.
if e.errno not in (errno.EAGAIN, errno.EALREADY,
errno.EWOULDBLOCK, errno.EINPROGRESS,
errno.EINTR):
raise SerialException('write failed: {}'.format(e))
except select.error as e:
# this is for Python 2.x
# ignore BlockingIOErrors and EINTR. all errors are shown
# see also http://www.python.org/dev/peps/pep-3151/#select
if e[0] not in (errno.EAGAIN, errno.EALREADY,
errno.EWOULDBLOCK, errno.EINPROGRESS,
errno.EINTR):
raise SerialException('write failed: {}'.format(e))
if not timeout.is_non_blocking and timeout.expired():
raise writeTimeoutError
return length - len(d)
def write(self, data):
"""\
Output the given byte string over the serial port. Can block if the
connection is blocked. May raise SerialException if the connection is
closed.
"""
if not self.is_open:
raise portNotOpenError
d = to_bytes(data)
tx_len = length = len(d)
timeout = Timeout(self._write_timeout)
while tx_len > 0:
try:
n = self._socket.send(d)
if timeout.is_non_blocking:
# Zero timeout indicates non-blocking - simply return the
# number of bytes of data actually written
return n
elif not timeout.is_infinite:
# when timeout is set, use select to wait for being ready
# with the time left as timeout
if timeout.expired():
raise writeTimeoutError
_, ready, _ = select.select([], [self._socket], [], timeout.time_left())
if not ready:
raise writeTimeoutError
else:
assert timeout.time_left() is None
# wait for write operation
_, ready, _ = select.select([], [self._socket], [], None)
if not ready:
raise SerialException('write failed (select)')
d = d[n:]
tx_len -= n
except SerialException:
raise
except OSError as e:
# this is for Python 3.x where select.error is a subclass of
# OSError ignore BlockingIOErrors and EINTR. other errors are shown
# https://www.python.org/dev/peps/pep-0475.
if e.errno not in (errno.EAGAIN, errno.EALREADY, errno.EWOULDBLOCK, errno.EINPROGRESS, errno.EINTR):
raise SerialException('write failed: {}'.format(e))
except select.error as e:
# this is for Python 2.x
# ignore BlockingIOErrors and EINTR. all errors are shown
# see also http://www.python.org/dev/peps/pep-3151/#select
if e[0] not in (errno.EAGAIN, errno.EALREADY, errno.EWOULDBLOCK, errno.EINPROGRESS, errno.EINTR):
raise SerialException('write failed: {}'.format(e))
if not timeout.is_non_blocking and timeout.expired():
raise writeTimeoutError
return length - len(d)
def write(self, data):
"""Output the given byte string over the serial port."""
if not self.is_open:
raise portNotOpenError
d = to_bytes(data)
tx_len = length = len(d)
timeout = Timeout(self._write_timeout)
while tx_len > 0:
try:
n = os.write(self.fd, d)
if timeout.is_non_blocking:
# Zero timeout indicates non-blocking - simply return the
# number of bytes of data actually written
return n
elif not timeout.is_infinite:
# when timeout is set, use select to wait for being ready
# with the time left as timeout
if timeout.expired():
raise writeTimeoutError
abort, ready, _ = select.select([self.pipe_abort_write_r],
[self.fd], [],
timeout.time_left())
if abort:
os.read(self.pipe_abort_write_r, 1000)
break
if not ready:
raise writeTimeoutError
else:
assert timeout.time_left() is None
# wait for write operation
abort, ready, _ = select.select([self.pipe_abort_write_r],
[self.fd], [], None)
if abort:
os.read(self.pipe_abort_write_r, 1)
break
if not ready:
raise SerialException('write failed (select)')
d = d[n:]
tx_len -= n
except SerialException:
raise
except OSError as v:
if v.errno != errno.EAGAIN:
raise SerialException('write failed: {}'.format(v))
# still calculate and check timeout
if timeout.expired():
raise writeTimeoutError
return length - len(d)
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()
read = bytearray()
timeout = Timeout(self._timeout)
poll = select.poll()
poll.register(self.fd, select.POLLIN | select.POLLERR | select.POLLHUP | select.POLLNVAL)
poll.register(self.pipe_abort_read_r, select.POLLIN | select.POLLERR | select.POLLHUP | select.POLLNVAL)
if size > 0:
while len(read) < size:
# print "\tread(): size",size, "have", len(read) #debug
# wait until device becomes ready to read (or something fails)
for fd, event in poll.poll(None if timeout.is_infinite else (timeout.time_left() * 1000)):
if fd == self.pipe_abort_read_r:
break
if event & (select.POLLERR | select.POLLHUP | select.POLLNVAL):
raise SerialException('device reports error (poll)')
# we don't care if it is select.POLLIN or timeout, that's
# handled below
if fd == self.pipe_abort_read_r:
os.read(self.pipe_abort_read_r, 1000)
break
buf = os.read(self.fd, size - len(read))
read.extend(buf)
if timeout.expired() \
or (self._inter_byte_timeout is not None and self._inter_byte_timeout > 0) and not buf:
break # early abort on timeout
return bytes(read)
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()
read = bytearray()
timeout = Timeout(self._timeout)
while len(read) < size:
try:
ready, _, _ = select.select([self.fd, self.pipe_abort_read_r],
[], [], timeout.time_left())
if self.pipe_abort_read_r in ready:
os.read(self.pipe_abort_read_r, 1000)
break
# If select was used with a timeout, and the timeout occurs, it
# returns with empty lists -> thus abort read operation.
# For timeout == 0 (non-blocking operation) also abort when
# there is nothing to read.
if not ready:
break # timeout
buf = os.read(self.fd, size - len(read))
except OSError as e:
# this is for Python 3.x where select.error is a subclass of
# OSError ignore BlockingIOErrors and EINTR. other errors are shown
# https://www.python.org/dev/peps/pep-0475.
if e.errno not in (errno.EAGAIN, errno.EALREADY,
errno.EWOULDBLOCK, errno.EINPROGRESS,
errno.EINTR):
raise SerialException('read failed: {}'.format(e))
except select.error as e:
# this is for Python 2.x
# ignore BlockingIOErrors and EINTR. all errors are shown
# see also http://www.python.org/dev/peps/pep-3151/#select
if e[0] not in (errno.EAGAIN, errno.EALREADY,
errno.EWOULDBLOCK, errno.EINPROGRESS,
errno.EINTR):
raise SerialException('read failed: {}'.format(e))
else:
# read should always return some data as select reported it was
# ready to read when we get to this point.
if not buf:
# Disconnected devices, at least on Linux, show the
# behavior that they are always ready to read immediately
# but reading returns nothing.
raise SerialException(
'device reports readiness to read but returned no data '
'(device disconnected or multiple access on port?)')
read.extend(buf)
if timeout.expired():
break
elif self._inter_byte_timeout is not None and self._inter_byte_timeout > 0:
#atleast one char received --> overwrite timeout by setting it to inter_byte_timeout
timeout = Timeout(self._inter_byte_timeout)
return bytes(read)
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()
read = bytearray()
timeout = Timeout(self._timeout)
while len(read) < size:
try:
ready, _, _ = select.select([self._socket], [], [],
timeout.time_left())
# If select was used with a timeout, and the timeout occurs, it
# returns with empty lists -> thus abort read operation.
# For timeout == 0 (non-blocking operation) also abort when
# there is nothing to read.
if not ready:
break # timeout
buf = self._socket.recv(size - len(read))
# read should always return some data as select reported it was
# ready to read when we get to this point, unless it is EOF
if not buf:
raise SerialException('socket disconnected')
read.extend(buf)
except OSError as e:
# this is for Python 3.x where select.error is a subclass of
# OSError ignore BlockingIOErrors and EINTR. other errors are shown
# https://www.python.org/dev/peps/pep-0475.
if e.errno not in (errno.EAGAIN, errno.EALREADY,
errno.EWOULDBLOCK, errno.EINPROGRESS,
errno.EINTR):
raise SerialException('read failed: {}'.format(e))
except (select.error, socket.error) as e:
# this is for Python 2.x
# ignore BlockingIOErrors and EINTR. all errors are shown
# see also http://www.python.org/dev/peps/pep-3151/#select
if e[0] not in (errno.EAGAIN, errno.EALREADY,
errno.EWOULDBLOCK, errno.EINPROGRESS,
errno.EINTR):
raise SerialException('read failed: {}'.format(e))
if timeout.expired():
break
return bytes(read)
def write(self, data):
"""Output the given byte string over the serial port."""
if not self.is_open:
raise portNotOpenError
d = to_bytes(data)
tx_len = len(d)
timeout = Timeout(self._write_timeout)
while tx_len > 0:
try:
n = os.write(self.fd, d)
if timeout.is_non_blocking:
# Zero timeout indicates non-blocking - simply return the
# number of bytes of data actually written
return n
elif not timeout.is_infinite:
# when timeout is set, use select to wait for being ready
# with the time left as timeout
if timeout.expired():
raise writeTimeoutError
abort, ready, _ = select.select([self.pipe_abort_write_r], [self.fd], [], timeout.time_left())
if abort:
os.read(self.pipe_abort_write_r, 1000)
break
if not ready:
raise writeTimeoutError
else:
assert timeout.time_left() is None
# wait for write operation
abort, ready, _ = select.select([self.pipe_abort_write_r], [self.fd], [], None)
if abort:
os.read(self.pipe_abort_write_r, 1)
break
if not ready:
raise SerialException('write failed (select)')
d = d[n:]
tx_len -= n
except SerialException:
raise
except OSError as v:
if v.errno != errno.EAGAIN:
raise SerialException('write failed: {}'.format(v))
# still calculate and check timeout
if timeout.expired():
raise writeTimeoutError
return len(data)
def read(self, size=1):
if not self.is_open:
raise portNotOpenError
data = bytearray()
try:
timeout = Timeout(self._timeout)
while len(data) < size:
if self._thread is None:
raise SerialException(
'connection failed (reader thread died)')
buf = self._read_buffer.get(True, timeout.time_left())
if buf is None:
return bytes(data)
data += buf
if timeout.expired():
break
except Queue.Empty: # -> timeout
pass
return bytes(data)
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
read = bytearray()
timeout = Timeout(self._timeout)
while len(read) < size:
try:
ready, _, _ = select.select([self._socket], [], [], timeout.time_left())
# If select was used with a timeout, and the timeout occurs, it
# returns with empty lists -> thus abort read operation.
# For timeout == 0 (non-blocking operation) also abort when
# there is nothing to read.
if not ready:
break # timeout
buf = self._socket.recv(size - len(read))
# read should always return some data as select reported it was
# ready to read when we get to this point, unless it is EOF
if not buf:
raise SerialException('socket disconnected')
read.extend(buf)
except OSError as e:
# this is for Python 3.x where select.error is a subclass of
# OSError ignore BlockingIOErrors and EINTR. other errors are shown
# https://www.python.org/dev/peps/pep-0475.
if e.errno not in (errno.EAGAIN, errno.EALREADY, errno.EWOULDBLOCK, errno.EINPROGRESS, errno.EINTR):
raise SerialException('read failed: {}'.format(e))
except (select.error, socket.error) as e:
# this is for Python 2.x
# ignore BlockingIOErrors and EINTR. all errors are shown
# see also http://www.python.org/dev/peps/pep-3151/#select
if e[0] not in (errno.EAGAIN, errno.EALREADY, errno.EWOULDBLOCK, errno.EINPROGRESS, errno.EINTR):
raise SerialException('read failed: {}'.format(e))
if timeout.expired():
break
return bytes(read)
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
read = bytearray()
timeout = Timeout(self._timeout)
while len(read) < size:
try:
ready, _, _ = select.select([self.fd, self.pipe_abort_read_r], [], [], timeout.time_left())
if self.pipe_abort_read_r in ready:
os.read(self.pipe_abort_read_r, 1000)
break
# If select was used with a timeout, and the timeout occurs, it
# returns with empty lists -> thus abort read operation.
# For timeout == 0 (non-blocking operation) also abort when
# there is nothing to read.
if not ready:
break # timeout
buf = os.read(self.fd, size - len(read))
# read should always return some data as select reported it was
# ready to read when we get to this point.
if not buf:
# Disconnected devices, at least on Linux, show the
# behavior that they are always ready to read immediately
# but reading returns nothing.
raise SerialException(
'device reports readiness to read but returned no data '
'(device disconnected or multiple access on port?)')
read.extend(buf)
except OSError as e:
# this is for Python 3.x where select.error is a subclass of
# OSError ignore EAGAIN errors. all other errors are shown
if e.errno != errno.EAGAIN and e.errno != errno.EINTR:
raise SerialException('read failed: {}'.format(e))
except select.error as e:
# this is for Python 2.x
# ignore EAGAIN errors. all other errors are shown
# see also http://www.python.org/dev/peps/pep-3151/#select
if e[0] != errno.EAGAIN:
raise SerialException('read failed: {}'.format(e))
if timeout.expired():
break
return bytes(read)
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
read = bytearray()
timeout = Timeout(self._timeout)
while len(read) < size:
try:
ready, _, _ = select.select([self.fd, self.pipe_abort_read_r],
[], [], timeout.time_left())
if self.pipe_abort_read_r in ready:
os.read(self.pipe_abort_read_r, 1000)
break
# If select was used with a timeout, and the timeout occurs, it
# returns with empty lists -> thus abort read operation.
# For timeout == 0 (non-blocking operation) also abort when
# there is nothing to read.
if not ready:
break # timeout
buf = os.read(self.fd, size - len(read))
# read should always return some data as select reported it was
# ready to read when we get to this point.
if not buf:
# Disconnected devices, at least on Linux, show the
# behavior that they are always ready to read immediately
# but reading returns nothing.
raise SerialException(
'device reports readiness to read but returned no data '
'(device disconnected or multiple access on port?)')
read.extend(buf)
except OSError as e:
# Devices connecting through a poor USB/Serial cable or an
# underpowered USB hub can spontaneously disconnect from
# the OS, and promptly reconnect. If this happens, attempt
# to reopen the device and continue the session.
if e.errno == errno.ENXIO:
retryTimeout = Timeout(2) # Allow for a short grace period
sys.stderr.write(
'pySerial WARNING: Serial device disappeared! '
'...Trying to reconnect...\n')
sys.stderr.write(
'pySerial WARNING: If this problem is chronic '
'replace your cable/powered USB HUB.\n')
sys.stderr.flush()
self.close()
while self.fd == None:
try:
self.open()
except OSError as e:
if e.errno != errno.ENOENT or retryTimeout.expired(
):
raise SerialException(
'Serial device gone: {}'.format(e))
break
# this is for Python 3.x where select.error is a subclass of
# OSError ignore BlockingIOErrors and EINTR. other errors are shown
# https://www.python.org/dev/peps/pep-0475.
elif e.errno not in (errno.EAGAIN, errno.EALREADY,
errno.EWOULDBLOCK, errno.EINPROGRESS,
errno.EINTR):
raise SerialException('read failed: {}'.format(e))
except select.error as e:
# this is for Python 2.x
# ignore BlockingIOErrors and EINTR. all errors are shown
# see also http://www.python.org/dev/peps/pep-3151/#select
if e[0] not in (errno.EAGAIN, errno.EALREADY,
errno.EWOULDBLOCK, errno.EINPROGRESS,
errno.EINTR):
raise SerialException('read failed: {}'.format(e))
if timeout.expired():
break
return bytes(read)
