def wait_for_read(sock_info, deadline):
"""Block until at least one byte is read, or a timeout, or a cancel."""
context = sock_info.cancel_context
# Only Monitor connections can be cancelled.
if context:
sock = sock_info.sock
while True:
# SSLSocket can have buffered data which won't be caught by select.
if hasattr(sock, 'pending') and sock.pending() > 0:
readable = True
else:
# Wait up to 500ms for the socket to become readable and then
# check for cancellation.
if deadline:
timeout = max(min(deadline - time.monotonic(), _POLL_TIMEOUT), 0.001)
else:
timeout = _POLL_TIMEOUT
readable = sock_info.socket_checker.select(
sock, read=True, timeout=timeout)
if context.cancelled:
raise _OperationCancelled('hello cancelled')
if readable:
return
if deadline and time.monotonic() > deadline:
raise socket.timeout("timed out")
def wait_for_read(sock_info, deadline):
"""Block until at least one byte is read, or a timeout, or a cancel."""
context = sock_info.cancel_context
# Only Monitor connections can be cancelled.
if context:
sock = sock_info.sock
timed_out = False
while True:
# SSLSocket can have buffered data which won't be caught by select.
if hasattr(sock, "pending") and sock.pending() > 0:
readable = True
else:
# Wait up to 500ms for the socket to become readable and then
# check for cancellation.
if deadline:
remaining = deadline - time.monotonic()
# When the timeout has expired perform one final check to
# see if the socket is readable. This helps avoid spurious
# timeouts on AWS Lambda and other FaaS environments.
if remaining <= 0:
timed_out = True
timeout = max(min(remaining, _POLL_TIMEOUT), 0)
else:
timeout = _POLL_TIMEOUT
readable = sock_info.socket_checker.select(sock,
read=True,
timeout=timeout)
if context.cancelled:
raise _OperationCancelled("hello cancelled")
if readable:
return
if timed_out:
raise socket.timeout("timed out")
