"""The U-Boot Module contains the UBootDriver"""
import logging
import attr
from pexpect import TIMEOUT
from ..factory import target_factory
from ..protocol import CommandProtocol, ConsoleProtocol, LinuxBootProtocol
from ..util import gen_marker, Timeout, re_vt100
from ..step import step
from .common import Driver
from .commandmixin import CommandMixin
[docs]@target_factory.reg_driver
@attr.s(eq=False)
class UBootDriver(CommandMixin, Driver, CommandProtocol, LinuxBootProtocol):
"""UBootDriver - Driver to control uboot via the console.
UBootDriver binds on top of a ConsoleProtocol.
Args:
prompt (str): optional, U-Boot prompt
password (str): optional, password to unlock U-Boot
init_commands (tuple): optional, tuple of commands to run after unlock
autoboot (str): optional, string to search for to interrupt autoboot
interrupt (str): optional, character to interrupt autoboot and go to prompt
password_prompt (str): optional, string to detect the password prompt
boot_expression (str): optional, deprecated
bootstring (str): optional, string that indicates that the Kernel is booting
boot_command (str): optional boot command to boot target
login_timeout (int): optional, timeout for login prompt detection
boot_timeout (int): optional, timeout for initial Linux Kernel version detection
"""
bindings = {"console": ConsoleProtocol, }
prompt = attr.ib(default="", validator=attr.validators.instance_of(str))
autoboot = attr.ib(default="stop autoboot", validator=attr.validators.instance_of(str))
password = attr.ib(default="", validator=attr.validators.instance_of(str))
interrupt = attr.ib(default="\n", validator=attr.validators.instance_of(str))
init_commands = attr.ib(default=attr.Factory(tuple), converter=tuple)
password_prompt = attr.ib(default="enter Password:", validator=attr.validators.instance_of(str))
boot_expression = attr.ib(default="", validator=attr.validators.instance_of(str))
bootstring = attr.ib(default=r"Linux version \d", validator=attr.validators.instance_of(str))
boot_command = attr.ib(default="run bootcmd", validator=attr.validators.instance_of(str))
boot_commands = attr.ib(default=attr.Factory(dict), validator=attr.validators.instance_of(dict))
login_timeout = attr.ib(default=30, validator=attr.validators.instance_of(int))
boot_timeout = attr.ib(default=30, validator=attr.validators.instance_of(int))
[docs] def __attrs_post_init__(self):
super().__attrs_post_init__()
self.logger = logging.getLogger(f"{self}:{self.target}")
self._status = 0
if self.boot_expression:
import warnings
warnings.warn("boot_expression is deprecated and will be ignored", DeprecationWarning)
[docs] def on_activate(self):
"""Activate the UBootDriver
This function checks for a prompt and awaits it if not already active
"""
if self._status == 0:
self._await_prompt()
[docs] def on_deactivate(self):
"""Deactivate the UBootDriver
Simply sets the internal status to 0
"""
self._status = 0
def _run(self, cmd: str, *, timeout: int = 30, codec: str = "utf-8", decodeerrors: str = "strict"): # pylint: disable=unused-argument,line-too-long
# TODO: use codec, decodeerrors
# TODO: Shell Escaping for the U-Boot Shell
marker = gen_marker()
cmp_command = f"""echo '{marker[:4]}''{marker[4:]}'; {cmd}; echo "$?"; echo '{marker[:4]}''{marker[4:]}';""" # pylint: disable=line-too-long
if self._status == 1:
self.console.sendline(cmp_command)
_, before, _, _ = self.console.expect(self.prompt, timeout=timeout)
# Remove VT100 Codes and split by newline
data = re_vt100.sub(
'', before.decode('utf-8'), count=1000000
).replace("\r", "").split("\n")
self.logger.debug("Received Data: %s", data)
# Remove first element, the invoked cmd
data = data[data.index(marker) + 1:]
data = data[:data.index(marker)]
exitcode = int(data[-1])
del data[-1]
return (data, [], exitcode)
return None
[docs] @Driver.check_active
@step(args=['cmd'], result=True)
def run(self, cmd, timeout=30):
"""
Runs the specified command on the shell and returns the output.
Args:
cmd (str): command to run on the shell
timeout (int): optional, how long to wait for completion
Returns:
Tuple[List[str],List[str], int]: if successful, None otherwise
"""
return self._run(cmd, timeout=timeout)
[docs] def get_status(self):
"""Retrieve status of the UBootDriver.
0 means inactive, 1 means active.
Returns:
int: status of the driver
"""
return self._status
def _check_prompt(self):
"""
Internal function to check if we have a valid prompt.
It sets the internal _status to 1 or 0 based on the prompt detection.
"""
marker = gen_marker()
# hide marker from expect
self.console.sendline(f"echo '{marker[:4]}''{marker[4:]}'")
try:
self.console.expect(f"{marker}", timeout=2)
self.console.expect(self.prompt, timeout=1)
self._status = 1
except TIMEOUT:
self._status = 0
raise
[docs] @Driver.check_active
@step()
def reset(self):
"""Reset the board via a CPU reset
"""
self._status = 0
self.console.sendline("reset")
self._await_prompt()
@step()
def _await_prompt(self):
"""Await autoboot line and stop it to get to the prompt, optionally
enter the password.
"""
timeout = Timeout(float(self.login_timeout))
# We call console.expect with a short timeout here to detect if the
# console is idle, which would result in a timeout without any changes
# to the before property. So we store the last before value we've seen.
# Because pexpect keeps any read data in it's buffer when a timeout
# occours, we can't lose any data this way.
last_before = None
expectations = [self.prompt, self.autoboot, self.password_prompt, TIMEOUT]
while True:
index, before, _, _ = self.console.expect(
expectations,
timeout=2
)
if index == 0:
self._status = 1
break
elif index == 1:
self.console.write(self.interrupt.encode('ASCII'))
elif index == 2:
if not self.password:
raise Exception("Password entry needed but no password set")
self.console.sendline(self.password)
elif index == 3:
# expect hit a timeout while waiting for a match
if before == last_before:
# we did not receive anything during the previous expect cycle
# let's assume the target is idle and we can safely issue a
# newline to check the state
self.console.sendline("")
if timeout.expired:
raise TIMEOUT(
f"Timeout of {self.login_timeout} seconds exceeded during waiting for login"
)
last_before = before
if self.prompt:
self._check_prompt()
for command in self.init_commands:
self._run_check(command)
[docs] @Driver.check_active
@step()
def await_boot(self):
"""Wait for the initial Linux version string to verify we successfully
jumped into the kernel.
"""
self.console.expect(self.bootstring, timeout=self.boot_timeout)
[docs] @Driver.check_active
@step(args=['name'])
def boot(self, name: str = ""):
"""Boot the default or a specific boot entry
Args:
name (str): name of the entry to boot"""
if name:
try:
self.console.sendline(self.boot_commands[name])
except KeyError as e:
raise Exception(f"{name} not found in boot_commands") from e
else:
self.console.sendline(self.boot_command)