blob: d0775a84b8a919fc147b8c7eba5f1662cd5d38b0 [file] [log] [blame]
# -*- coding: utf-8 -*-
# Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
"""Common python commands used by various build scripts."""
from __future__ import print_function
import collections
import contextlib
from datetime import datetime
import email.utils
import errno
import functools
import getpass
import hashlib
import inspect
import os
import pprint
import re
import signal
import socket
import subprocess
import sys
import tempfile
import time
import traceback
import types
from chromite.lib import constants
from chromite.lib import cros_collections
from chromite.lib import cros_logging as logging
from chromite.lib import signals
# For use by ShellQuote. Match all characters that the shell might treat
# specially. This means a number of things:
# - Reserved characters.
# - Characters used in expansions (brace, variable, path, globs, etc...).
# - Characters that an interactive shell might use (like !).
# - Whitespace so that one arg turns into multiple.
# See the bash man page as well as the POSIX shell documentation for more info:
_SHELL_QUOTABLE_CHARS = frozenset('[|&;()<> \t!{}[]=*?~$"\'\\#^')
# The chars that, when used inside of double quotes, need escaping.
# Order here matters as we need to escape backslashes first.
# The number of files is larger than this, we will use -T option
# and files to be added may not show up to the command line.
def ShellQuote(s):
"""Quote |s| in a way that is safe for use in a shell.
We aim to be safe, but also to produce "nice" output. That means we don't
use quotes when we don't need to, and we prefer to use less quotes (like
putting it all in single quotes) than more (using double quotes and escaping
a bunch of stuff, or mixing the quotes).
While python does provide a number of alternatives like:
- pipes.quote
- shlex.quote
They suffer from various problems like:
- Not widely available in different python versions.
- Do not produce pretty output in many cases.
- Are in modules that rarely otherwise get used.
Note: We don't handle reserved shell words like "for" or "case". This is
because those only matter when they're the first element in a command, and
there is no use case for that. When we want to run commands, we tend to
run real programs and not shell ones.
s: The string to quote.
A safely (possibly quoted) string.
s = s.encode('utf-8')
# See if no quoting is needed so we can return the string as-is.
for c in s:
if not s:
return "''"
return s
# See if we can use single quotes first. Output is nicer.
if "'" not in s:
return "'%s'" % s
# Have to use double quotes. Escape the few chars that still expand when
# used inside of double quotes.
if c in s:
s = s.replace(c, r'\%s' % c)
return '"%s"' % s
def TruncateStringToLine(s, maxlen=80):
"""Truncate |s| to a maximum length of |maxlen| including elipsis (...)
s: A string.
maxlen: Maximum length of desired returned string. Must be at least 3.
s if len(s) <= maxlen already and s has no newline in it.
Otherwise, a single line truncation that ends with '...' and is of
length |maxlen|.
assert maxlen >= 3
line = s.splitlines()[0]
if len(line) <= maxlen:
return line
return line[:maxlen-3] + '...'
def ShellUnquote(s):
"""Do the opposite of ShellQuote.
This function assumes that the input is a valid escaped string. The behaviour
is undefined on malformed strings.
s: An escaped string.
The unescaped version of the string.
if not s:
return ''
if s[0] == "'":
return s[1:-1]
if s[0] != '"':
return s
s = s[1:-1]
output = ''
i = 0
while i < len(s) - 1:
# Skip the backslash when it makes sense.
if s[i] == '\\' and s[i + 1] in _SHELL_ESCAPE_CHARS:
i += 1
output += s[i]
i += 1
return output + s[i] if i < len(s) else output
def CmdToStr(cmd):
"""Translate a command list into a space-separated string.
The resulting string should be suitable for logging messages and for
pasting into a terminal to run. Command arguments are surrounded by
quotes to keep them grouped, even if an argument has spaces in it.
['a', 'b'] ==> "'a' 'b'"
['a b', 'c'] ==> "'a b' 'c'"
['a', 'b\'c'] ==> '\'a\' "b\'c"'
[u'a', "/'$b"] ==> '\'a\' "/\'$b"'
[] ==> ''
See unittest for additional (tested) examples.
cmd: List of command arguments.
String representing full command.
# Use str before repr to translate unicode strings to regular strings.
return ' '.join(ShellQuote(arg) for arg in cmd)
class CommandResult(object):
"""An object to store various attributes of a child process."""
def __init__(self, cmd=None, error=None, output=None, returncode=None):
self.cmd = cmd
self.error = error
self.output = output
self.returncode = returncode
def cmdstr(self):
"""Return self.cmd as a space-separated string, useful for log messages."""
return CmdToStr(self.cmd or '')
class RunCommandError(Exception):
"""Error caught in RunCommand() method."""
def __init__(self, msg, result, exception=None):
self.msg, self.result, self.exception = msg, result, exception
if exception is not None and not isinstance(exception, Exception):
raise ValueError('exception must be an exception instance; got %r'
% (exception,))
Exception.__init__(self, msg)
self.args = (msg, result, exception)
def Stringify(self, error=True, output=True):
"""Custom method for controlling what is included in stringifying this.
Each individual argument is the literal name of an attribute
on the result object; if False, that value is ignored for adding
to this string content. If true, it'll be incorporated.
error: See comment about individual arguments above.
output: See comment about individual arguments above.
items = [
'return code: %s; command: %s' % (
self.result.returncode, self.result.cmdstr),
if error and self.result.error:
if output and self.result.output:
if self.msg:
return '\n'.join(items)
def __str__(self):
# __str__ needs to return ascii, thus force a conversion to be safe.
return self.Stringify().decode('utf-8', 'replace').encode(
'ascii', 'xmlcharrefreplace')
def __eq__(self, other):
return (isinstance(other, type(self)) and
self.args == other.args)
def __ne__(self, other):
return not self.__eq__(other)
class TerminateRunCommandError(RunCommandError):
"""We were signaled to shutdown while running a command.
Client code shouldn't generally know, nor care about this class. It's
used internally to suppress retry attempts when we're signaled to die.
def SudoRunCommand(cmd, user='root', preserve_env=False, **kwargs):
"""Run a command via sudo.
Client code must use this rather than coming up with their own RunCommand
invocation that jams sudo in- this function is used to enforce certain
rules in our code about sudo usage, and as a potential auditing point.
cmd: The command to run. See RunCommand for rules of this argument-
SudoRunCommand purely prefixes it with sudo.
user: The user to run the command as.
preserve_env (bool): Whether to preserve the environment.
kwargs: See RunCommand options, it's a direct pass thru to it.
Note that this supports a 'strict' keyword that defaults to True.
If set to False, it'll suppress strict sudo behavior.
See RunCommand documentation.
This function may immediately raise RunCommandError if we're operating
in a strict sudo context and the API is being misused.
Barring that, see RunCommand's documentation- it can raise the same things
RunCommand does.
sudo_cmd = ['sudo']
strict = kwargs.pop('strict', True)
if user == 'root' and os.geteuid() == 0:
return RunCommand(cmd, **kwargs)
if strict and STRICT_SUDO:
if 'CROS_SUDO_KEEP_ALIVE' not in os.environ:
raise RunCommandError(
'We were invoked in a strict sudo non - interactive context, but no '
'sudo keep alive daemon is running. This is a bug in the code.',
CommandResult(cmd=cmd, returncode=126))
sudo_cmd += ['-n']
if user != 'root':
sudo_cmd += ['-u', user]
if preserve_env:
sudo_cmd += ['--preserve-env']
# Pass these values down into the sudo environment, since sudo will
# just strip them normally.
extra_env = kwargs.pop('extra_env', None)
extra_env = {} if extra_env is None else extra_env.copy()
for var in constants.ENV_PASSTHRU:
if var not in extra_env and var in os.environ:
extra_env[var] = os.environ[var]
sudo_cmd.extend('%s=%s' % (k, v) for k, v in extra_env.iteritems())
# Finally, block people from passing options to sudo.
if isinstance(cmd, basestring):
# We need to handle shell ourselves so the order is correct:
# $ sudo [sudo args] -- bash -c '[shell command]'
# If we let RunCommand take care of it, we'd end up with:
# $ bash -c 'sudo [sudo args] -- [shell command]'
shell = kwargs.pop('shell', False)
if not shell:
raise Exception('Cannot run a string command without a shell')
sudo_cmd.extend(['/bin/bash', '-c', cmd])
return RunCommand(sudo_cmd, **kwargs)
def _KillChildProcess(proc, int_timeout, kill_timeout, cmd, original_handler,
signum, frame):
"""Used as a signal handler by RunCommand.
This is internal to Runcommand. No other code should use this.
if signum:
# If we've been invoked because of a signal, ignore delivery of that signal
# from this point forward. The invoking context of _KillChildProcess
# restores signal delivery to what it was prior; we suppress future delivery
# till then since this code handles SIGINT/SIGTERM fully including
# delivering the signal to the original handler on the way out.
signal.signal(signum, signal.SIG_IGN)
# Do not trust Popen's returncode alone; we can be invoked from contexts where
# the Popen instance was created, but no process was generated.
if proc.returncode is None and is not None:
while proc.poll_lock_breaker() is None and int_timeout >= 0:
int_timeout -= 0.1
while proc.poll_lock_breaker() is None and kill_timeout >= 0:
kill_timeout -= 0.1
if proc.poll_lock_breaker() is None:
# Still doesn't want to die. Too bad, so sad, time to die.
except EnvironmentError as e:
logging.warning('Ignoring unhandled exception in _KillChildProcess: %s',
# Ensure our child process has been reaped.
kwargs = {}
if sys.version_info.major >= 3:
# ... but don't wait forever.
kwargs['timeout'] = 60
if not signals.RelaySignal(original_handler, signum, frame):
# Mock up our own, matching exit code for signaling.
cmd_result = CommandResult(cmd=cmd, returncode=signum << 8)
raise TerminateRunCommandError('Received signal %i' % signum, cmd_result)
class _Popen(subprocess.Popen):
"""subprocess.Popen derivative customized for our usage.
Specifically, we fix terminate/send_signal/kill to work if the child process
was a setuid binary; on vanilla kernels, the parent can wax the child
regardless, on goobuntu this apparently isn't allowed, thus we fall back
to the sudo machinery we have.
While we're overriding send_signal, we also suppress ESRCH being raised
if the process has exited, and suppress signaling all together if the process
has knowingly been waitpid'd already.
def send_signal(self, signum):
if self.returncode is not None:
# The original implementation in Popen would allow signaling whatever
# process now occupies this pid, even if the Popen object had waitpid'd.
# Since we can escalate to sudo kill, we do not want to allow that.
# Fixing this addresses that angle, and makes the API less sucky in the
# process.
os.kill(, signum)
except EnvironmentError as e:
if e.errno == errno.EPERM:
# Kill returns either 0 (signal delivered), or 1 (signal wasn't
# delivered). This isn't particularly informative, but we still
# need that info to decide what to do, thus the error_code_ok=True.
ret = SudoRunCommand(['kill', '-%i' % signum, str(],
print_cmd=False, redirect_stdout=True,
redirect_stderr=True, error_code_ok=True)
if ret.returncode == 1:
# The kill binary doesn't distinguish between permission denied,
# and the pid is missing. Denied can only occur under weird
# grsec/selinux policies. We ignore that potential and just
# assume the pid was already dead and try to reap it.
elif e.errno == errno.ESRCH:
# Since we know the process is dead, reap it now.
# Normally Popen would throw this error- we suppress it since frankly
# that's a misfeature and we're already overriding this method.
def _lock_breaker(self, func, *args, **kwargs):
"""Helper to manage the waitpid lock.
# If the lock doesn't exist, or is not locked, call the func directly.
lock = getattr(self, '_waitpid_lock', None)
if lock is not None and lock.locked():
return func(*args, **kwargs)
if not lock.locked():
return func(*args, **kwargs)
def poll_lock_breaker(self, *args, **kwargs):
"""Wrapper around poll() to break locks if needed."""
return self._lock_breaker(self.poll, *args, **kwargs)
def wait_lock_breaker(self, *args, **kwargs):
"""Wrapper around wait() to break locks if needed."""
return self._lock_breaker(self.wait, *args, **kwargs)
# pylint: disable=redefined-builtin
def RunCommand(cmd, print_cmd=True, error_message=None, redirect_stdout=False,
redirect_stderr=False, cwd=None, input=None, enter_chroot=False,
shell=False, env=None, extra_env=None, ignore_sigint=False,
combine_stdout_stderr=False, log_stdout_to_file=None,
append_to_file=False, chroot_args=None, debug_level=logging.INFO,
error_code_ok=False, int_timeout=1, kill_timeout=1,
log_output=False, stdout_to_pipe=False, capture_output=False,
quiet=False, mute_output=None):
"""Runs a command.
cmd: cmd to run. Should be input to subprocess.Popen. If a string, shell
must be true. Otherwise the command must be an array of arguments, and
shell must be false.
print_cmd: prints the command before running it.
error_message: prints out this message when an error occurs.
redirect_stdout: returns the stdout.
redirect_stderr: holds stderr output until input is communicated.
cwd: the working directory to run this cmd.
input: The data to pipe into this command through stdin. If a file object
or file descriptor, stdin will be connected directly to that.
enter_chroot: this command should be run from within the chroot. If set,
cwd must point to the scripts directory. If we are already inside the
chroot, this command will be run as if |enter_chroot| is False.
shell: Controls whether we add a shell as a command interpreter. See cmd
since it has to agree as to the type.
env: If non-None, this is the environment for the new process. If
enter_chroot is true then this is the environment of the enter_chroot,
most of which gets removed from the cmd run.
extra_env: If set, this is added to the environment for the new process.
In enter_chroot=True case, these are specified on the post-entry
side, and so are often more useful. This dictionary is not used to
clear any entries though.
ignore_sigint: If True, we'll ignore signal.SIGINT before calling the
child. This is the desired behavior if we know our child will handle
Ctrl-C. If we don't do this, I think we and the child will both get
Ctrl-C at the same time, which means we'll forcefully kill the child.
combine_stdout_stderr: Combines stdout and stderr streams into stdout.
log_stdout_to_file: If set, redirects stdout to file specified by this path.
If |combine_stdout_stderr| is set to True, then stderr will also be logged
to the specified file.
append_to_file: If True, the stdout streams are appended to the end of log
chroot_args: An array of arguments for the chroot environment wrapper.
debug_level: The debug level of RunCommand's output.
error_code_ok: Does not raise an exception when command returns a non-zero
exit code. Instead, returns the CommandResult object containing the exit
code. Note: will still raise an exception if the cmd file does not exist.
int_timeout: If we're interrupted, how long (in seconds) should we give the
invoked process to clean up before we send a SIGTERM.
kill_timeout: If we're interrupted, how long (in seconds) should we give the
invoked process to shutdown from a SIGTERM before we SIGKILL it.
log_output: Log the command and its output automatically.
stdout_to_pipe: Redirect stdout to pipe.
capture_output: Set |redirect_stdout| and |redirect_stderr| to True.
quiet: Set |print_cmd| to False, |stdout_to_pipe| and
|combine_stdout_stderr| to True.
mute_output: Mute subprocess printing to parent stdout/stderr. Defaults to
None, which bases muting on |debug_level|.
A CommandResult object.
RunCommandError: Raises exception on error with optional error_message.
if capture_output:
redirect_stdout, redirect_stderr = True, True
if quiet:
debug_level = logging.DEBUG
stdout_to_pipe, combine_stdout_stderr = True, True
# Set default for variables.
stdout = None
stderr = None
stdin = None
cmd_result = CommandResult()
if mute_output is None:
mute_output = logging.getLogger().getEffectiveLevel() > debug_level
# Force the timeout to float; in the process, if it's not convertible,
# a self-explanatory exception will be thrown.
kill_timeout = float(kill_timeout)
def _get_tempfile():
return tempfile.TemporaryFile(bufsize=0)
except EnvironmentError as e:
if e.errno != errno.ENOENT:
# This can occur if we were pointed at a specific location for our
# TMP, but that location has since been deleted. Suppress that issue
# in this particular case since our usage gurantees deletion,
# and since this is primarily triggered during hard cgroups shutdown.
return tempfile.TemporaryFile(bufsize=0, dir='/tmp')
# Modify defaults based on parameters.
# Note that tempfiles must be unbuffered else attempts to read
# what a separate process did to that file can result in a bad
# view of the file.
if log_stdout_to_file:
if append_to_file:
stdout = open(log_stdout_to_file, 'a+')
stdout = open(log_stdout_to_file, 'w+')
elif stdout_to_pipe:
stdout = subprocess.PIPE
elif redirect_stdout or mute_output or log_output:
stdout = _get_tempfile()
if combine_stdout_stderr:
stderr = subprocess.STDOUT
elif redirect_stderr or mute_output or log_output:
stderr = _get_tempfile()
# If subprocesses have direct access to stdout or stderr, they can bypass
# our buffers, so we need to flush to ensure that output is not interleaved.
if stdout is None or stderr is None:
# If input is a string, we'll create a pipe and send it through that.
# Otherwise we assume it's a file object that can be read from directly.
if isinstance(input, basestring):
stdin = subprocess.PIPE
elif input is not None:
stdin = input
input = None
if isinstance(cmd, basestring):
if not shell:
raise Exception('Cannot run a string command without a shell')
cmd = ['/bin/bash', '-c', cmd]
shell = False
elif shell:
raise Exception('Cannot run an array command with a shell')
# If we are using enter_chroot we need to use enterchroot pass env through
# to the final command.
env = env.copy() if env is not None else os.environ.copy()
# Looking at localized error messages may be unexpectedly dangerous, so we
# set LC_MESSAGES=C to make sure the output of commands is safe to inspect.
env['LC_MESSAGES'] = 'C'
env.update(extra_env if extra_env else {})
if enter_chroot and not IsInsideChroot():
wrapper = ['cros_sdk']
if cwd:
# If the current working directory is set, try to find cros_sdk relative
# to cwd. Generally cwd will be the buildroot therefore we want to use
# {cwd}/chromite/bin/cros_sdk. For more info PTAL at
path = os.path.join(cwd, constants.CHROMITE_BIN_SUBDIR, 'cros_sdk')
if os.path.exists(path):
wrapper = [path]
if chroot_args:
wrapper += chroot_args
if extra_env:
wrapper.extend('%s=%s' % (k, v) for k, v in extra_env.iteritems())
cmd = wrapper + ['--'] + cmd
for var in constants.ENV_PASSTHRU:
if var not in env and var in os.environ:
env[var] = os.environ[var]
# Print out the command before running.
if print_cmd or log_output:
if cwd:
logging.log(debug_level, 'RunCommand: %s in %s', CmdToStr(cmd), cwd)
logging.log(debug_level, 'RunCommand: %s', CmdToStr(cmd))
cmd_result.cmd = cmd
proc = None
# Verify that the signals modules is actually usable, and won't segfault
# upon invocation of getsignal. See signals.SignalModuleUsable for the
# details and upstream python bug.
use_signals = signals.SignalModuleUsable()
proc = _Popen(cmd, cwd=cwd, stdin=stdin, stdout=stdout,
stderr=stderr, shell=False, env=env,
if use_signals:
if ignore_sigint:
old_sigint = signal.signal(signal.SIGINT, signal.SIG_IGN)
old_sigint = signal.getsignal(signal.SIGINT)
functools.partial(_KillChildProcess, proc, int_timeout,
kill_timeout, cmd, old_sigint))
old_sigterm = signal.getsignal(signal.SIGTERM)
functools.partial(_KillChildProcess, proc, int_timeout,
kill_timeout, cmd, old_sigterm))
(cmd_result.output, cmd_result.error) = proc.communicate(input)
if use_signals:
signal.signal(signal.SIGINT, old_sigint)
signal.signal(signal.SIGTERM, old_sigterm)
if stdout and not log_stdout_to_file and not stdout_to_pipe:
cmd_result.output =
if stderr and stderr != subprocess.STDOUT:
cmd_result.error =
cmd_result.returncode = proc.returncode
if log_output:
if cmd_result.output:
logging.log(debug_level, '(stdout):\n%s', cmd_result.output)
if cmd_result.error:
logging.log(debug_level, '(stderr):\n%s', cmd_result.error)
if not error_code_ok and proc.returncode:
msg = 'cmd=%s' % cmd
if cwd:
msg += ', cwd=%s' % cwd
if extra_env:
msg += ', extra env=%s' % extra_env
if error_message:
msg += '\n%s' % error_message
raise RunCommandError(msg, cmd_result)
except OSError as e:
estr = str(e)
if e.errno == errno.EACCES:
estr += '; does the program need `chmod a+x`?'
raise RunCommandError(estr, CommandResult(cmd=cmd), exception=e)
if proc is not None:
# Ensure the process is dead.
_KillChildProcess(proc, int_timeout, kill_timeout, cmd, None, None, None)
return cmd_result
# pylint: enable=redefined-builtin
# Convenience RunCommand methods.
# We don't use functools.partial because it binds the methods at import time,
# which doesn't work well with unit tests, since it bypasses the mock that may
# be set up for RunCommand.
def DebugRunCommand(*args, **kwargs):
kwargs.setdefault('debug_level', logging.DEBUG)
return RunCommand(*args, **kwargs)
class DieSystemExit(SystemExit):
"""Custom Exception used so we can intercept this if necessary."""
def Die(message, *args, **kwargs):
"""Emits an error message with a stack trace and halts execution.
message: The message to be emitted before exiting.
logging.error(message, *args, **kwargs)
raise DieSystemExit(1)
def GetSysrootToolPath(sysroot, tool_name):
"""Returns the path to the sysroot specific version of a tool.
Does not check that the tool actually exists.
sysroot: build root of the system in question.
tool_name: string name of tool desired (e.g. 'equery').
string path to tool inside the sysroot.
if sysroot == '/':
return os.path.join(sysroot, 'usr', 'bin', tool_name)
return os.path.join(sysroot, 'build', 'bin', tool_name)
def ListFiles(base_dir):
"""Recursively list files in a directory.
base_dir: directory to start recursively listing in.
A list of files relative to the base_dir path or
An empty list of there are no files in the directories.
directories = [base_dir]
files_list = []
while directories:
directory = directories.pop()
for name in os.listdir(directory):
fullpath = os.path.join(directory, name)
if os.path.isfile(fullpath):
elif os.path.isdir(fullpath):
return files_list
def IsInsideChroot():
"""Returns True if we are inside chroot."""
return os.path.exists('/etc/cros_chroot_version')
def IsOutsideChroot():
"""Returns True if we are outside chroot."""
return not IsInsideChroot()
def AssertInsideChroot():
"""Die if we are outside the chroot"""
if not IsInsideChroot():
Die('%s: please run inside the chroot', os.path.basename(sys.argv[0]))
def AssertOutsideChroot():
"""Die if we are inside the chroot"""
if IsInsideChroot():
Die('%s: please run outside the chroot', os.path.basename(sys.argv[0]))
def GetChromeosVersion(str_obj):
"""Helper method to parse output for CHROMEOS_VERSION_STRING.
str_obj: a string, which may contain Chrome OS version info.
A string, value of CHROMEOS_VERSION_STRING environment variable set by Or None if not found.
if str_obj is not None:
match ='CHROMEOS_VERSION_STRING=([0-9_.]+)', str_obj)
if match and'CHROMEOS_VERSION_STRING = %s',
return None
def GetHostName(fully_qualified=False):
"""Return hostname of current machine, with domain if |fully_qualified|."""
hostname = socket.gethostname()
hostname = socket.gethostbyaddr(hostname)[0]
except (socket.gaierror, socket.herror) as e:
logging.warning('please check your /etc/hosts file; resolving your hostname'
' (%s) failed: %s', hostname, e)
if fully_qualified:
return hostname
return hostname.partition('.')[0]
def GetHostDomain():
"""Return domain of current machine.
If there is no domain, return 'localdomain'.
hostname = GetHostName(fully_qualified=True)
domain = hostname.partition('.')[2]
return domain if domain else 'localdomain'
def HostIsCIBuilder(fq_hostname=None, golo_only=False, gce_only=False):
"""Return True iff a host is a continuous-integration builder.
fq_hostname: The fully qualified hostname. By default, we fetch it for you.
golo_only: Only return True if the host is in the Chrome Golo. Defaults to
gce_only: Only return True if the host is in the Chrome GCE block. Defaults
to False.
if not fq_hostname:
fq_hostname = GetHostName(fully_qualified=True)
in_golo = fq_hostname.endswith('.' + constants.GOLO_DOMAIN)
in_gce = (fq_hostname.endswith('.' + constants.CHROME_DOMAIN) or
fq_hostname.endswith('.' + constants.CHROMEOS_BOT_INTERNAL))
if golo_only:
return in_golo
elif gce_only:
return in_gce
return in_golo or in_gce
def FindCompressor(compression, chroot=None):
"""Locate a compressor utility program (possibly in a chroot).
Since we compress/decompress a lot, make it easy to locate a
suitable utility program in a variety of locations. We favor
the one in the chroot over /, and the parallel implementation
over the single threaded one.
compression: The type of compression desired.
chroot: Optional path to a chroot to search.
Path to a compressor.
ValueError: If compression is unknown.
if compression == COMP_GZIP:
std = 'gzip'
para = 'pigz'
elif compression == COMP_BZIP2:
std = 'bzip2'
para = 'pbzip2'
elif compression == COMP_XZ:
std = 'xz'
para = 'pixz'
elif compression == COMP_NONE:
return 'cat'
raise ValueError('unknown compression')
roots = []
if chroot:
for prog in [para, std]:
for root in roots:
for subdir in ['', 'usr']:
path = os.path.join(root, subdir, 'bin', prog)
if os.path.exists(path):
return path
return std
def CompressionStrToType(s):
"""Convert a compression string type to a constant.
s: string to check
A constant, or None if the compression type is unknown.
'gz': COMP_GZIP,
'bz2': COMP_BZIP2,
'xz': COMP_XZ,
if s:
return _COMP_STR.get(s)
return COMP_NONE
def CompressionExtToType(file_name):
"""Retrieve a compression type constant from a compression file's name.
file_name: Name of a compression file.
A constant, return COMP_NONE if the extension is unknown.
ext = os.path.splitext(file_name)[-1]
'.tgz': COMP_GZIP,
'.gz': COMP_GZIP,
'.tbz2': COMP_BZIP2,
'.bz2': COMP_BZIP2,
'.txz': COMP_XZ,
'.xz': COMP_XZ,
return _COMP_EXT.get(ext, COMP_NONE)
def CompressFile(infile, outfile):
"""Compress a file using compressor specified by |outfile| suffix.
infile: File to compress.
outfile: Name of output file. Compression used is based on the
type of suffix of the name specified (e.g.: .bz2).
comp_type = CompressionExtToType(outfile)
assert comp_type and comp_type != COMP_NONE
comp = FindCompressor(comp_type)
if os.path.basename(comp) == 'pixz':
# pixz does not accept '-c'; instead an explicit '-i' indicates input file
# should not be deleted, and '-o' specifies output file.
cmd = [comp, '-i', infile, '-o', outfile]
cmd = [comp, '-c', infile]
RunCommand(cmd, log_stdout_to_file=outfile)
def UncompressFile(infile, outfile):
"""Uncompress a file using compressor specified by |infile| suffix.
infile: File to uncompress. Compression used is based on the
type of suffix of the name specified (e.g.: .bz2).
outfile: Name of output file.
comp_type = CompressionExtToType(infile)
assert comp_type and comp_type != COMP_NONE
comp = FindCompressor(comp_type)
if os.path.basename(comp) == 'pixz':
# pixz does not accept '-c'; instead an explicit '-i' indicates input file
# should not be deleted, and '-o' specifies output file.
cmd = [comp, '-d', '-i', infile, '-o', outfile]
cmd = [comp, '-dc', infile]
RunCommand(cmd, log_stdout_to_file=outfile)
class CreateTarballError(RunCommandError):
"""Error while running tar.
We may run tar multiple times because of "soft" errors. The result is from
the last RunCommand instance.
def CreateTarball(target, cwd, sudo=False, compression=COMP_XZ, chroot=None,
inputs=None, timeout=300, extra_args=None, **kwargs):
"""Create a tarball. Executes 'tar' on the commandline.
target: The path of the tar file to generate.
cwd: The directory to run the tar command.
sudo: Whether to run with "sudo".
compression: The type of compression desired. See the FindCompressor
function for details.
chroot: See FindCompressor().
inputs: A list of files or directories to add to the tarball. If unset,
defaults to ".".
timeout: The number of seconds to wait on soft failure.
extra_args: A list of extra args to pass to "tar".
kwargs: Any RunCommand options/overrides to use.
The cmd_result object returned by the RunCommand invocation.
CreateTarballError: if the tar command failed, possibly after retry.
if inputs is None:
inputs = ['.']
if extra_args is None:
extra_args = []
kwargs.setdefault('debug_level', logging.INFO)
comp = FindCompressor(compression, chroot=chroot)
cmd = (['tar'] +
extra_args +
['--sparse', '-I', comp, '-cf', target])
if len(inputs) > _THRESHOLD_TO_USE_T_FOR_TAR:
cmd += ['--null', '-T', '/dev/stdin']
rc_input = '\0'.join(inputs)
cmd += list(inputs)
rc_input = None
rc_func = SudoRunCommand if sudo else RunCommand
# If tar fails with status 1, retry twice. Once after timeout seconds and
# again 2*timeout seconds after that.
for try_count in range(3):
result = rc_func(cmd, cwd=cwd,
**dict(kwargs, error_code_ok=True, input=rc_input))
if result.returncode == 0:
return result
if result.returncode != 1 or try_count > 1:
# Since the build is abandoned at this point, we will take 5
# entire minutes to track down the competing process.
raise CreateTarballError('CreateTarball', result)
assert result.returncode == 1
time.sleep(timeout * (try_count + 1))
logging.warning('CreateTarball: tar: source modification time changed ' +
'(see, retrying')
def GetInput(prompt):
"""Helper function to grab input from a user. Makes testing easier."""
return raw_input(prompt)
def GetChoice(title, options, group_size=0):
"""Ask user to choose an option from the list.
When |group_size| is 0, then all items in |options| will be extracted and
shown at the same time. Otherwise, the items will be extracted |group_size|
at a time, and then shown to the user. This makes it easier to support
generators that are slow, extremely large, or people usually want to pick
from the first few choices.
title: The text to display before listing options.
options: Iterable which provides options to display.
group_size: How many options to show before asking the user to choose.
An integer of the index in |options| the user picked.
def PromptForChoice(max_choice, more):
prompt = 'Please choose an option [0-%d]' % max_choice
if more:
prompt += ' (Enter for more options)'
prompt += ': '
while True:
choice = GetInput(prompt)
if more and not choice.strip():
return None
choice = int(choice)
except ValueError:
print('Input is not an integer')
if choice < 0 or choice > max_choice:
print('Choice %d out of range (0-%d)' % (choice, max_choice))
return choice
max_choice = 0
for i, opt in enumerate(options):
if i and group_size and not i % group_size:
choice = PromptForChoice(i - 1, True)
if choice is not None:
return choice
print(' [%d]: %s' % (i, opt))
max_choice = i
return PromptForChoice(max_choice, False)
def BooleanPrompt(prompt='Do you want to continue?', default=True,
true_value='yes', false_value='no', prolog=None):
"""Helper function for processing boolean choice prompts.
prompt: The question to present to the user.
default: Boolean to return if the user just presses enter.
true_value: The text to display that represents a True returned.
false_value: The text to display that represents a False returned.
prolog: The text to display before prompt.
True or False.
true_value, false_value = true_value.lower(), false_value.lower()
true_text, false_text = true_value, false_value
if true_value == false_value:
raise ValueError('true_value and false_value must differ: got %r'
% true_value)
if default:
true_text = true_text[0].upper() + true_text[1:]
false_text = false_text[0].upper() + false_text[1:]
prompt = ('\n%s (%s/%s)? ' % (prompt, true_text, false_text))
if prolog:
prompt = ('\n%s\n%s' % (prolog, prompt))
while True:
response = GetInput(prompt).lower()
except EOFError:
# If the user hits CTRL+D, or stdin is disabled, use the default.
response = None
except KeyboardInterrupt:
# If the user hits CTRL+C, just exit the process.
Die('CTRL+C detected; exiting')
if not response:
return default
if true_value.startswith(response):
if not false_value.startswith(response):
return True
# common prefix between the two...
elif false_value.startswith(response):
return False
def BooleanShellValue(sval, default, msg=None):
"""See if the string value is a value users typically consider as boolean
Often times people set shell variables to different values to mean "true"
or "false". For example, they can do:
export FOO=yes
export BLAH=1
export MOO=true
Handle all that user ugliness here.
If the user picks an invalid value, you can use |msg| to display a non-fatal
warning rather than raising an exception.
sval: The string value we got from the user.
default: If we can't figure out if the value is true or false, use this.
msg: If |sval| is an unknown value, use |msg| to warn the user that we
could not decode the input. Otherwise, raise ValueError().
The interpreted boolean value of |sval|.
ValueError() if |sval| is an unknown value and |msg| is not set.
if sval is None:
return default
if isinstance(sval, basestring):
s = sval.lower()
if s in ('yes', 'y', '1', 'true'):
return True
elif s in ('no', 'n', '0', 'false'):
return False
if msg is not None:
logging.warning('%s: %r', msg, sval)
return default
raise ValueError('Could not decode as a boolean value: %r' % sval)
# Suppress whacked complaints about abstract class being unused.
class MasterPidContextManager(object):
"""Allow context managers to restrict their exit to within the same PID."""
# In certain cases we actually want this ran outside
# of the main pid- specifically in backup processes
# doing cleanup.
def __init__(self):
self._invoking_pid = None
def __enter__(self):
self._invoking_pid = os.getpid()
return self._enter()
def __exit__(self, exc_type, exc, exc_tb):
curpid = os.getpid()
if curpid == self.ALTERNATE_MASTER_PID:
self._invoking_pid = curpid
if curpid == self._invoking_pid:
return self._exit(exc_type, exc, exc_tb)
def _enter(self):
raise NotImplementedError(self, '_enter')
def _exit(self, exc_type, exc, exc_tb):
raise NotImplementedError(self, '_exit')
def NoOpContextManager():
def AllowDisabling(enabled, functor, *args, **kwargs):
"""Context Manager wrapper that can be used to enable/disable usage.
This is mainly useful to control whether or not a given Context Manager
is used.
For example:
with AllowDisabling(options.timeout <= 0, Timeout, options.timeout):
... do code w/in a timeout context..
If options.timeout is a positive integer, then the_Timeout context manager is
created and ran. If it's zero or negative, then the timeout code is disabled.
While Timeout *could* handle this itself, it's redundant having each
implementation do this, thus the generic wrapper.
if enabled:
return functor(*args, **kwargs)
return NoOpContextManager()
class ContextManagerStack(object):
"""Context manager that is designed to safely allow nesting and stacking.
Python2.7 directly supports a with syntax generally removing the need for
this, although this form avoids indentation hell if there is a lot of context
managers. It also permits more programmatic control and allowing conditional
For Python2.6, see; the short
version is that there is a race in the available stdlib/language rules under
2.6 when dealing w/ multiple context managers, thus this safe version was
For each context manager added to this instance, it will unwind them,
invoking them as if it had been constructed as a set of manually nested
with statements.
def __init__(self):
self._stack = []
def Add(self, functor, *args, **kwargs):
"""Add a context manager onto the stack.
Usage of this is essentially the following:
>>> stack.add(Timeout, 60)
It must be done in this fashion, else there is a mild race that exists
between context manager instantiation and initial __enter__.
Invoking it in the form specified eliminates that race.
functor: A callable to instantiate a context manager.
args and kwargs: positional and optional args to functor.
The newly created (and __enter__'d) context manager.
Note: This is not the same value as the "with" statement -- that returns
the value from the __enter__ function while this is the manager itself.
obj = None
obj = functor(*args, **kwargs)
return obj
if obj is not None:
def __enter__(self):
# Nothing to do in this case. The individual __enter__'s are done
# when the context managers are added, which will likely be after
# the __enter__ method of this stack is called.
return self
def __exit__(self, exc_type, exc, exc_tb):
# Exit each context manager in stack in reverse order, tracking the results
# to know whether or not to suppress the exception raised (or to switch that
# exception to a new one triggered by an individual handler's __exit__).
for handler in reversed(self._stack):
# pylint: disable=bare-except
if handler.__exit__(exc_type, exc, exc_tb):
exc_type = exc = exc_tb = None
exc_type, exc, exc_tb = sys.exc_info()
self._stack = []
# Return True if any exception was handled.
if all(x is None for x in (exc_type, exc, exc_tb)):
return True
# Raise any exception that is left over from exiting all context managers.
# Normally a single context manager would return False to allow caller to
# re-raise the exception itself, but here the exception might have been
# raised during the exiting of one of the individual context managers.
raise exc_type, exc, exc_tb
class ApiMismatchError(Exception):
"""Raised by GetTargetChromiteApiVersion."""
class NoChromiteError(Exception):
"""Raised when an expected chromite installation was missing."""
def GetTargetChromiteApiVersion(buildroot, validate_version=True):
"""Get the re-exec API version of the target chromite.
buildroot: The directory containing the chromite to check.
validate_version: If set to true, checks the target chromite for
compatibility, and raises an ApiMismatchError when there is an
The version number in (major, minor) tuple.
May raise an ApiMismatchError if validate_version is set.
api = RunCommand(
[constants.PATH_TO_CBUILDBOT, '--reexec-api-version'],
cwd=buildroot, error_code_ok=True, capture_output=True)
except RunCommandError:
# Although error_code_ok=True was used, this exception will still be raised
# if the executible did not exist.
full_cbuildbot_path = os.path.join(buildroot, constants.PATH_TO_CBUILDBOT)
if not os.path.exists(full_cbuildbot_path):
raise NoChromiteError('No cbuildbot found in buildroot %s, expected to '
'find %s. ' % (buildroot, full_cbuildbot_path))
# If the command failed, then we're targeting a cbuildbot that lacks the
# option; assume 0:0 (ie, initial state).
major = minor = 0
if api.returncode == 0:
major, minor = map(int, api.output.strip().split('.', 1))
if validate_version and major != constants.REEXEC_API_MAJOR:
raise ApiMismatchError(
'The targeted version of chromite in buildroot %s requires '
'api version %i, but we are api version %i. We cannot proceed.'
% (buildroot, major, constants.REEXEC_API_MAJOR))
return major, minor
def iflatten_instance(iterable, terminate_on_kls=(basestring,)):
"""Derivative of snakeoil.lists.iflatten_instance; flatten an object.
Given an object, flatten it into a single depth iterable-
stopping descent on objects that either aren't iterable, or match
isinstance(obj, terminate_on_kls).
>>> print list(iflatten_instance([1, 2, "as", ["4", 5]))
[1, 2, "as", "4", 5]
def descend_into(item):
if isinstance(item, terminate_on_kls):
return False
except TypeError:
return False
# Note strings can be infinitely descended through- thus this
# recursion limiter.
return not isinstance(item, basestring) or len(item) > 1
if not descend_into(iterable):
yield iterable
for item in iterable:
if not descend_into(item):
yield item
for subitem in iflatten_instance(item, terminate_on_kls):
yield subitem
# TODO: Remove this once we move to snakeoil.
def load_module(name):
"""load a module
name: python dotted namespace path of the module to import
imported module
FailedImport if importing fails
m = __import__(name)
# __import__('') returns foo, so...
for bit in name.split('.')[1:]:
m = getattr(m, bit)
return m
def PredicateSplit(func, iterable):
"""Splits an iterable into two groups based on a predicate return value.
func: A functor that takes an item as its argument and returns a boolean
value indicating which group the item belongs.
iterable: The collection to split.
A tuple containing two lists, the first containing items that func()
returned True for, and the second containing items that func() returned
False for.
trues, falses = [], []
for x in iterable:
(trues if func(x) else falses).append(x)
return trues, falses
def Open(obj, mode='r'):
"""Convenience ctx that accepts a file path or an already open file object."""
if isinstance(obj, basestring):
with open(obj, mode=mode) as f:
yield f
yield obj
def LoadKeyValueFile(obj, ignore_missing=False, multiline=False):
"""Turn a key=value file into a dict
Note: If you're designing a new data store, please use json rather than
this format. This func is designed to work with legacy/external files
where json isn't an option.
obj: The file to read. Can be a path or an open file object.
ignore_missing: If the file does not exist, return an empty dict.
multiline: Allow a value enclosed by quotes to span multiple lines.
a dict of all the key=value pairs found in the file.
d = {}
with Open(obj) as f:
key = None
in_quotes = None
for raw_line in f:
line = raw_line.split('#')[0]
if not line.strip():
# Continue processing a multiline value.
if multiline and in_quotes and key:
if line.rstrip()[-1] == in_quotes:
# Wrap up the multiline value if the line ends with a quote.
d[key] += line.rstrip()[:-1]
in_quotes = None
d[key] += line
chunks = line.split('=', 1)
if len(chunks) != 2:
raise ValueError('Malformed key=value file %r; line %r'
% (obj, raw_line))
key = chunks[0].strip()
val = chunks[1].strip()
if len(val) >= 2 and val[0] in "\"'" and val[0] == val[-1]:
# Strip matching quotes on the same line.
val = val[1:-1]
elif val and multiline and val[0] in "\"'":
# Unmatched quote here indicates a multiline value. Do not
# strip the '\n' at the end of the line.
in_quotes = val[0]
val = chunks[1].lstrip()[1:]
d[key] = val
except EnvironmentError as e:
if not (ignore_missing and e.errno == errno.ENOENT):
return d
def SafeRun(functors, combine_exceptions=False):
"""Executes a list of functors, continuing on exceptions.
functors: An iterable of functors to call.
combine_exceptions: If set, and multiple exceptions are encountered,
SafeRun will raise a RuntimeError containing a list of all the exceptions.
If only one exception is encountered, then the default behavior of
re-raising the original exception with unmodified stack trace will be
The first exception encountered, with corresponding backtrace, unless
|combine_exceptions| is specified and there is more than one exception
encountered, in which case a RuntimeError containing a list of all the
exceptions that were encountered is raised.
errors = []
for f in functors:
except Exception as e:
# Append the exception object and the traceback.
errors.append((e, sys.exc_info()[2]))
if errors:
if len(errors) == 1 or not combine_exceptions:
# To preserve the traceback.
inst, tb = errors[0]
raise inst, None, tb
raise RuntimeError([e[0] for e in errors])
def UserDateTimeFormat(timeval=None):
"""Format a date meant to be viewed by a user
The focus here is to have a format that is easily readable by humans,
but still easy (and unambiguous) for a machine to parse. Hence, we
use the RFC 2822 date format (with timezone name appended).
timeval: Either a datetime object or a floating point time value as accepted
by gmtime()/localtime(). If None, the current time is used.
A string format such as 'Wed, 20 Feb 2013 15:25:15 -0500 (EST)'
if isinstance(timeval, datetime):
timeval = time.mktime(timeval.timetuple())
return '%s (%s)' % (email.utils.formatdate(timeval=timeval, localtime=True),
time.strftime('%Z', time.localtime(timeval)))
def GetCommonPathPrefix(paths):
"""Get the longest common directory of |paths|.
paths: A list of absolute directory or file paths.
Absolute path to the longest directory common to |paths|, with no
trailing '/'.
return os.path.dirname(os.path.commonprefix(paths))
def ParseUserDateTimeFormat(time_string):
"""Parse a time string into a floating point time value.
This function is essentially the inverse of UserDateTimeFormat.
time_string: A string datetime represetation in RFC 2822 format, such as
'Wed, 20 Feb 2013 15:25:15 -0500 (EST)'.
Floating point Unix timestamp (seconds since epoch).
return email.utils.mktime_tz(email.utils.parsedate_tz(time_string))
def GetDefaultBoard():
"""Gets the default board.
The default board (as a string), or None if either the default board
file was missing or malformed.
default_board_file_name = os.path.join(constants.SOURCE_ROOT, 'src',
'scripts', '.default_board')
with open(default_board_file_name) as default_board_file:
default_board =
# Check for user typos like whitespace
if not re.match('[a-zA-Z0-9-_]*$', default_board):
logging.warning('Noticed invalid default board: |%s|. Ignoring this '
'default.', default_board)
default_board = None
except IOError:
return None
return default_board
def SetDefaultBoard(board):
"""Set the default board.
board (str): The name of the board to save as the default.
bool - True if successfully wrote default, False otherwise.
config_path = os.path.join(constants.CROSUTILS_DIR, '.default_board')
with open(config_path, 'w') as f:
except IOError as e:
logging.error('Unable to write default board: %s', e.message)
return False
return True
def GetBoard(device_board, override_board=None, force=False):
"""Gets the board name to use.
Ask user to confirm when |override_board| and |device_board| are
both None.
device_board: The board detected on the device.
override_board: Overrides the board.
force: Force using the default board if |device_board| is None.
Returns the first non-None board in the following order:
|override_board|, |device_board|, and GetDefaultBoard().
DieSystemExit: If user enters no.
if override_board:
return override_board
board = device_board or GetDefaultBoard()
if not device_board:
msg = 'Cannot detect board name; using default board %s.' % board
if not force and not BooleanPrompt(default=False, prolog=msg):
return board
class AttributeFrozenError(Exception):
"""Raised when frozen attribute value is modified."""
class FrozenAttributesClass(type):
"""Metaclass for any class to support freezing attribute values.
This metaclass can be used by any class to add the ability to
freeze attribute values with the Freeze method.
Use by adding this line in a class:
__metaclass__ = FrozenAttributesClass
_FROZEN_ERR_MSG = 'Attribute values are frozen, cannot alter %s.'
def __new__(mcs, clsname, bases, scope):
# Create Freeze method that freezes current attributes.
if 'Freeze' in scope:
raise TypeError('Class %s has its own Freeze method, cannot use with'
' the FrozenAttributesClass metaclass.' % clsname)
# Make sure cls will have _FROZEN_ERR_MSG set.
scope.setdefault('_FROZEN_ERR_MSG', mcs._FROZEN_ERR_MSG)
# Create the class.
# pylint: disable=bad-super-call
cls = super(FrozenAttributesClass, mcs).__new__(mcs, clsname, bases, scope)
# Replace cls.__setattr__ with the one that honors freezing.
orig_setattr = cls.__setattr__
def SetAttr(obj, name, value):
"""If the object is frozen then abort."""
# pylint: disable=protected-access
if getattr(obj, '_frozen', False):
raise AttributeFrozenError(obj._FROZEN_ERR_MSG % name)
if isinstance(orig_setattr, types.MethodType):
orig_setattr(obj, name, value)
super(cls, obj).__setattr__(name, value)
cls.__setattr__ = SetAttr
# Add new cls.Freeze method.
def Freeze(obj):
# pylint: disable=protected-access
obj._frozen = True
cls.Freeze = Freeze
return cls
class FrozenAttributesMixin(object):
"""Alternate mechanism for freezing attributes in a class.
If an existing class is not a new-style class then it will be unable to
use the FrozenAttributesClass metaclass directly. Simply use this class
as a mixin instead to accomplish the same thing.
__metaclass__ = FrozenAttributesClass
def GetIPv4Address(dev=None, global_ip=True):
"""Returns any global/host IP address or the IP address of the given device.
socket.gethostname() is insufficient for machines where the host files are
not set up "correctly." Since some of our builders may have this issue,
this method gives you a generic way to get the address so you are reachable
either via a VM or remote machine on the same network.
dev: Get the IP address of the device (e.g. 'eth0').
global_ip: If set True, returns a globally valid IP address. Otherwise,
returns a local IP address (default: True).
cmd = ['ip', 'addr', 'show']
cmd += ['scope', 'global' if global_ip else 'host']
cmd += [] if dev is None else ['dev', dev]
result = RunCommand(cmd, print_cmd=False, capture_output=True)
matches = re.findall(r'\binet (\d+\.\d+\.\d+\.\d+).*', result.output)
if matches:
return matches[0]
logging.warning('Failed to find ip address in %r', result.output)
return None
def GetSysroot(board=None):
"""Returns the sysroot for |board| or '/' if |board| is None."""
return '/' if board is None else os.path.join('/build', board)
# Structure to hold the values produced by TimedSection.
# Attributes:
# start: The absolute start time as a datetime.
# finish: The absolute finish time as a datetime, or None if in progress.
# delta: The runtime as a timedelta, or None if in progress.
TimedResults = cros_collections.Collection(
'TimedResults', start=None, finish=None, delta=None)
def TimedSection():
"""Context manager to time how long a code block takes.
with cros_build_lib.TimedSection() as timer:
DoWork()'DoWork took %s',
Context manager value will be a TimedResults instance.
# Create our context manager value.
times = TimedResults(
yield times
times.finish = = times.finish - times.start
PartitionInfo = collections.namedtuple(
['number', 'start', 'end', 'size', 'file_system', 'name', 'flags']
def _ParseParted(lines):
"""Returns partition information from `parted print` output."""
ret = []
# Sample output (partition #, start, end, size, file system, name, flags):
# /foo/chromiumos_qemu_image.bin:3360MB:file:512:512:gpt:;
# 11:0.03MB:8.42MB:8.39MB::RWFW:;
# 6:8.42MB:8.42MB:0.00MB::KERN-C:;
# 7:8.42MB:8.42MB:0.00MB::ROOT-C:;
# 9:8.42MB:8.42MB:0.00MB::reserved:;
# 10:8.42MB:8.42MB:0.00MB::reserved:;
# 2:10.5MB:27.3MB:16.8MB::KERN-A:;
# 4:27.3MB:44.0MB:16.8MB::KERN-B:;
# 8:44.0MB:60.8MB:16.8MB:ext4:OEM:;
# 12:128MB:145MB:16.8MB:fat16:EFI-SYSTEM:boot;
# 5:145MB:2292MB:2147MB::ROOT-B:;
# 3:2292MB:4440MB:2147MB:ext2:ROOT-A:;
# 1:4440MB:7661MB:3221MB:ext4:STATE:;
pattern = re.compile(r'(([^:]*:){6}[^:]*);')
for line in lines:
match = pattern.match(line)
if match:
d = dict(zip(PartitionInfo._fields,':')))
# Disregard any non-numeric partition number (e.g. the file path).
if d['number'].isdigit():
d['number'] = int(d['number'])
for key in ['start', 'end', 'size']:
d[key] = float(d[key][:-1])
return ret
def _ParseCgpt(lines):
"""Returns partition information from `cgpt show` output."""
# start size part contents
# 1921024 2097152 1 Label: "STATE"
# Type: Linux data
# UUID: EEBD83BE-397E-BD44-878B-0DDDD5A5C510
# 20480 32768 2 Label: "KERN-A"
# Type: ChromeOS kernel
# UUID: 7007C2F3-08E5-AB40-A4BC-FF5B01F5460D
# Attr: priority=15 tries=15 successful=1
start_pattern = re.compile(r'''\s+(\d+)\s+(\d+)\s+(\d+)\s+Label: "(.+)"''')
ret = []
line_no = 0
while line_no < len(lines):
line = lines[line_no]
line_no += 1
m = start_pattern.match(line)
if not m:
start, size, number, label = m.groups()
number = int(number)
start = int(start) * 512
size = int(size) * 512
end = start + size
ret.append(PartitionInfo(number=number, start=start, end=end, size=size,
name=label, file_system='', flags=''))
return ret
def GetImageDiskPartitionInfo(image_path):
"""Returns the disk partition table of an image.
image_path: Path to the image file.
A list of ParitionInfo items.
if IsInsideChroot():
# Inside chroot, use `cgpt`.
cmd = ['cgpt', 'show', image_path]
func = _ParseCgpt
# Outside chroot, use `parted`.
cmd = ['parted', '-m', image_path, 'unit', 'B', 'print']
func = _ParseParted
lines = RunCommand(
extra_env={'PATH': '/sbin:%s' % os.environ['PATH'], 'LC_ALL': 'C'},
return func(lines)
def GetRandomString(length=20):
"""Returns a random string of |length|."""
md5 = hashlib.md5(os.urandom(length))
return md5.hexdigest()
def MachineDetails():
"""Returns a string to help identify the source of a job.
This is not meant for machines to parse; instead, we want content that is easy
for humans to read when trying to figure out where "something" is coming from.
For example, when a service has grabbed a lock in Google Storage, and we want
to see what process actually triggered that (in case it is a test gone rogue),
the content in here should help triage.
Note: none of the details included may be secret so they can be freely pasted
into bug reports/chats/logs/etc...
Note: this content should not be large
A string with content that helps identify this system/process/etc...
return '\n'.join((
'PROG=%s' % inspect.stack()[-1][1],
'USER=%s' % getpass.getuser(),
'HOSTNAME=%s' % GetHostName(fully_qualified=True),
'PID=%s' % os.getpid(),
'TIMESTAMP=%s' % UserDateTimeFormat(),
'RANDOM_JUNK=%s' % GetRandomString(),
)) + '\n'
def FormatDetailedTraceback(exc_info=None):
"""Generate a traceback including details like local variables.
exc_info: The exception tuple to format; defaults to sys.exc_info().
See the help on that function for details on the type.
A string of the formatted |exc_info| details.
if exc_info is None:
exc_info = sys.exc_info()
ret = []
# pylint: disable=unpacking-non-sequence
exc_type, exc_value, exc_tb = exc_info
if exc_type:
ret += [
'Traceback (most recent call last):\n',
'Note: Call args reflect *current* state, not *entry* state\n',
while exc_tb:
frame = exc_tb.tb_frame
ret += traceback.format_tb(exc_tb, 1)
args = inspect.getargvalues(frame)
_, _, fname, _ = traceback.extract_tb(exc_tb, 1)[0]
ret += [
' Call: %s%s\n' % (fname, inspect.formatargvalues(*args)),
' Locals:\n',
if frame.f_locals:
keys = sorted(frame.f_locals.keys(), key=str.lower)
keylen = max(len(x) for x in keys)
typelen = max(len(str(type(x))) for x in frame.f_locals.values())
for key in keys:
val = frame.f_locals[key]
ret += [' %-*s: %-*s %s\n' %
(keylen, key, typelen, type(val), pprint.saferepr(val))]
exc_tb = exc_tb.tb_next
if exc_type:
ret += traceback.format_exception_only(exc_type, exc_value)
# Help python with its circular references.
del exc_tb
return ''.join(ret)
def PrintDetailedTraceback(exc_info=None, file=None):
"""Print a traceback including details like local variables.
exc_info: The exception tuple to format; defaults to sys.exc_info().
See the help on that function for details on the type.
file: The file object to write the details to; defaults to sys.stderr.
# We use |file| to match the existing traceback API.
# pylint: disable=redefined-builtin
if exc_info is None:
exc_info = sys.exc_info()
if file is None:
file = sys.stderr
# Try to print out extended details on the current exception.
# If that fails, still fallback to the normal exception path.
curr_exc_info = exc_info
output = FormatDetailedTraceback()
if output:
print(output, file=file)
except Exception:
print('Could not decode extended exception details:', file=file)
traceback.print_exception(*curr_exc_info, file=sys.stdout)
# Help python with its circular references.
del exc_info
del curr_exc_info
class _FdCapturer(object):
"""Helper class to capture output at the file descriptor level.
This is meant to be used with sys.stdout or sys.stderr. By capturing
file descriptors, this will also intercept subprocess output, which
reassigning sys.stdout or sys.stderr will not do.
Output will only be captured, it will no longer be printed while
the capturer is active.
def __init__(self, source, output=None):
"""Construct the _FdCapturer object.
Does not start capturing until Start() is called.
source: A file object to capture. Typically sys.stdout or
sys.stderr, but will work with anything that implements flush()
and fileno().
output: A file name where the captured output is to be stored. If None,
then the output will be stored to a temporary file.
self._source = source
self._captured = ''
self._saved_fd = None
self._tempfile = None
self._capturefile = None
self._capturefile_reader = None
self._capturefile_name = output
def _SafeCreateTempfile(self, tempfile_obj):
"""Ensure that the tempfile is created safely.
(1) Stash away a reference to the tempfile.
(2) Unlink the file from the filesystem.
(2) ensures that if we crash, the file gets deleted. (1) ensures that while
we are running, we hold a reference to the file so the system does not close
the file.
tempfile_obj: A tempfile object.
self._tempfile = tempfile_obj
def Start(self):
"""Begin capturing output."""
if self._capturefile_name is None:
tempfile_obj = tempfile.NamedTemporaryFile(delete=False)
self._capturefile = tempfile_obj.file
self._capturefile_name =
self._capturefile_reader = open(self._capturefile_name)
# Open file passed in for writing. Set buffering=1 for line level
# buffering.
self._capturefile = open(self._capturefile_name, 'w', buffering=1)
self._capturefile_reader = open(self._capturefile_name)
# Save the original fd so we can revert in Stop().
self._saved_fd = os.dup(self._source.fileno())
os.dup2(self._capturefile.fileno(), self._source.fileno())
def Stop(self):
"""Stop capturing output."""
if self._saved_fd is not None:
os.dup2(self._saved_fd, self._source.fileno())
self._saved_fd = None
# If capturefile and capturefile_reader exist, close them as they were
# opened in self.Start().
if self._capturefile_reader is not None:
self._capturefile_reader = None
if self._capturefile is not None:
self._capturefile = None
def GetCaptured(self):
"""Return all output captured up to this point.
Can be used while capturing or after Stop() has been called.
if self._capturefile_reader is not None:
self._captured +=
return self._captured
def ClearCaptured(self):
"""Erase all captured output."""
self._captured = ''
class OutputCapturer(object):
"""Class for capturing stdout/stderr output.
Class is designed as a 'ContextManager'.
with cros_build_lib.OutputCapturer() as output:
# Capturing of stdout/stderr automatically starts now.
# Do stuff that sends output to stdout/stderr.
# Capturing automatically stops at end of 'with' block.
# stdout/stderr can be retrieved from the OutputCapturer object:
stdout = output.GetStdoutLines() # Or other access methods
# Some Assert methods are only valid if capturing was used in test.
self.AssertOutputContainsError() # Or other related methods
# OutputCapturer can also be used to capture output to specified files.
with self.OutputCapturer(stdout_path='/tmp/stdout.txt') as output:
# Do stuff.
# stdout will be captured to /tmp/stdout.txt.
OPER_MSG_SPLIT_RE = re.compile(r'^\033\[1;.*?\033\[0m$|^[^\n]*$',
__slots__ = ['_stdout_capturer', '_stderr_capturer', '_quiet_fail']
def __init__(self, stdout_path=None, stderr_path=None, quiet_fail=False):
"""Initalize OutputCapturer with capture files.
If OutputCapturer is initialized with filenames to capture stdout and stderr
to, then those files are used. Otherwise, temporary files are created.
stdout_path: File to capture stdout to. If None, a temporary file is used.
stderr_path: File to capture stderr to. If None, a temporary file is used.
quiet_fail: If True fail quietly without printing the captured stdout and
self._stdout_capturer = _FdCapturer(sys.stdout, output=stdout_path)
self._stderr_capturer = _FdCapturer(sys.stderr, output=stderr_path)
self._quiet_fail = quiet_fail
def __enter__(self):
# This method is called with entering 'with' block.
return self
def __exit__(self, exc_type, exc_val, exc_tb):
# This method is called when exiting 'with' block.
if exc_type and not self._quiet_fail:
print('Exception during output capturing: %r' % (exc_val,))
stdout = self.GetStdout()
if stdout:
print('Captured stdout was:\n%s' % stdout)
print('No captured stdout')
stderr = self.GetStderr()
if stderr:
print('Captured stderr was:\n%s' % stderr)
print('No captured stderr')
def StartCapturing(self):
"""Begin capturing stdout and stderr."""
def StopCapturing(self):
"""Stop capturing stdout and stderr."""
def ClearCaptured(self):
"""Clear any captured stdout/stderr content."""
def GetStdout(self):
"""Return captured stdout so far."""
return self._stdout_capturer.GetCaptured()
def GetStderr(self):
"""Return captured stderr so far."""
return self._stderr_capturer.GetCaptured()
def _GetOutputLines(self, output, include_empties):
"""Split |output| into lines, optionally |include_empties|.
Return array of lines.
lines = self.OPER_MSG_SPLIT_RE.findall(output)
if not include_empties:
lines = [ln for ln in lines if ln]
return lines
def GetStdoutLines(self, include_empties=True):
"""Return captured stdout so far as array of lines.
If |include_empties| is false filter out all empty lines.
return self._GetOutputLines(self.GetStdout(), include_empties)
def GetStderrLines(self, include_empties=True):
"""Return captured stderr so far as array of lines.
If |include_empties| is false filter out all empty lines.
return self._GetOutputLines(self.GetStderr(), include_empties)