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tools/mpremote: Avoid initial blocking read in read_until().

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If the target does not return any data then `read_until()` will block
indefinitely.  Fix this by making the initial read part of the general read
look, which always checks `inWaiting() > 0` before reading from the serial
device.

Also added the UART timeout to the constructor.  This is not currently used
but may be used as an additional safeguard.

Signed-off-by: Hans Maerki <buhtig.hans.maerki@ergoinfo.ch>
This commit is contained in:
Hans Maerki
2025-01-26 18:00:38 +01:00
committed by Damien George
parent 55ca3fd675
commit 0d46e45a1f
1 changed files with 21 additions and 11 deletions
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32
tools/mpremote/mpremote/transport_serial.py
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@@ -42,7 +42,7 @@ from .transport import TransportError, TransportExecError, Transport
class SerialTransport(Transport):
def __init__(self, device, baudrate=115200, wait=0, exclusive=True):
def __init__(self, device, baudrate=115200, wait=0, exclusive=True, timeout=None):
self.in_raw_repl = False
self.use_raw_paste = True
self.device_name = device
@@ -52,7 +52,11 @@ class SerialTransport(Transport):
import serial.tools.list_ports
# Set options, and exclusive if pyserial supports it
serial_kwargs = {"baudrate": baudrate, "interCharTimeout": 1}
serial_kwargs = {
"baudrate": baudrate,
"timeout": timeout,
"interCharTimeout": 1,
}
if serial.__version__ >= "3.3":
serial_kwargs["exclusive"] = exclusive
@@ -95,13 +99,20 @@ class SerialTransport(Transport):
self.serial.close()
def read_until(self, min_num_bytes, ending, timeout=10, data_consumer=None):
# if data_consumer is used then data is not accumulated and the ending must be 1 byte long
assert data_consumer is None or len(ending) == 1
"""
min_num_bytes: Obsolete.
ending: Return if 'ending' matches.
timeout [s]: Return if timeout between characters. None: Infinite timeout.
data_consumer: Use callback for incoming characters.
If data_consumer is used then data is not accumulated and the ending must be 1 byte long
data = self.serial.read(min_num_bytes)
if data_consumer:
data_consumer(data)
timeout_count = 0
It is not visible to the caller why the function returned. It could be ending or timeout.
"""
assert data_consumer is None or len(ending) == 1
assert isinstance(timeout, (type(None), int, float))
data = b""
begin_char_s = time.monotonic()
while True:
if data.endswith(ending):
break
@@ -112,10 +123,9 @@ class SerialTransport(Transport):
data = new_data
else:
data = data + new_data
timeout_count = 0
begin_char_s = time.monotonic()
else:
timeout_count += 1
if timeout is not None and timeout_count >= 100 * timeout:
if timeout is not None and time.monotonic() >= begin_char_s + timeout:
break
time.sleep(0.01)
return data