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Diffstat (limited to 'third_party/catapult/devil/devil/utils/cmd_helper.py')
| -rw-r--r-- | third_party/catapult/devil/devil/utils/cmd_helper.py | 394 |
1 files changed, 0 insertions, 394 deletions
diff --git a/third_party/catapult/devil/devil/utils/cmd_helper.py b/third_party/catapult/devil/devil/utils/cmd_helper.py deleted file mode 100644 index 06c105f..0000000 --- a/third_party/catapult/devil/devil/utils/cmd_helper.py +++ /dev/null @@ -1,394 +0,0 @@ -# Copyright (c) 2012 The Chromium Authors. All rights reserved. -# Use of this source code is governed by a BSD-style license that can be -# found in the LICENSE file. - -"""A wrapper for subprocess to make calling shell commands easier.""" - -import logging -import os -import pipes -import select -import signal -import string -import StringIO -import subprocess -import sys -import time - -# fcntl is not available on Windows. -try: - import fcntl -except ImportError: - fcntl = None - -logger = logging.getLogger(__name__) - -_SafeShellChars = frozenset(string.ascii_letters + string.digits + '@%_-+=:,./') - - -def SingleQuote(s): - """Return an shell-escaped version of the string using single quotes. - - Reliably quote a string which may contain unsafe characters (e.g. space, - quote, or other special characters such as '$'). - - The returned value can be used in a shell command line as one token that gets - to be interpreted literally. - - Args: - s: The string to quote. - - Return: - The string quoted using single quotes. - """ - return pipes.quote(s) - - -def DoubleQuote(s): - """Return an shell-escaped version of the string using double quotes. - - Reliably quote a string which may contain unsafe characters (e.g. space - or quote characters), while retaining some shell features such as variable - interpolation. - - The returned value can be used in a shell command line as one token that gets - to be further interpreted by the shell. - - The set of characters that retain their special meaning may depend on the - shell implementation. This set usually includes: '$', '`', '\', '!', '*', - and '@'. - - Args: - s: The string to quote. - - Return: - The string quoted using double quotes. - """ - if not s: - return '""' - elif all(c in _SafeShellChars for c in s): - return s - else: - return '"' + s.replace('"', '\\"') + '"' - - -def ShrinkToSnippet(cmd_parts, var_name, var_value): - """Constructs a shell snippet for a command using a variable to shrink it. - - Takes into account all quoting that needs to happen. - - Args: - cmd_parts: A list of command arguments. - var_name: The variable that holds var_value. - var_value: The string to replace in cmd_parts with $var_name - - Returns: - A shell snippet that does not include setting the variable. - """ - def shrink(value): - parts = (x and SingleQuote(x) for x in value.split(var_value)) - with_substitutions = ('"$%s"' % var_name).join(parts) - return with_substitutions or "''" - - return ' '.join(shrink(part) for part in cmd_parts) - - -def Popen(args, stdout=None, stderr=None, shell=None, cwd=None, env=None): - # preexec_fn isn't supported on windows. - if sys.platform == 'win32': - preexec_fn = None - else: - preexec_fn = lambda: signal.signal(signal.SIGPIPE, signal.SIG_DFL) - - return subprocess.Popen( - args=args, cwd=cwd, stdout=stdout, stderr=stderr, - shell=shell, close_fds=True, env=env, preexec_fn=preexec_fn) - - -def Call(args, stdout=None, stderr=None, shell=None, cwd=None, env=None): - pipe = Popen(args, stdout=stdout, stderr=stderr, shell=shell, cwd=cwd, - env=env) - pipe.communicate() - return pipe.wait() - - -def RunCmd(args, cwd=None): - """Opens a subprocess to execute a program and returns its return value. - - Args: - args: A string or a sequence of program arguments. The program to execute is - the string or the first item in the args sequence. - cwd: If not None, the subprocess's current directory will be changed to - |cwd| before it's executed. - - Returns: - Return code from the command execution. - """ - logger.info(str(args) + ' ' + (cwd or '')) - return Call(args, cwd=cwd) - - -def GetCmdOutput(args, cwd=None, shell=False): - """Open a subprocess to execute a program and returns its output. - - Args: - args: A string or a sequence of program arguments. The program to execute is - the string or the first item in the args sequence. - cwd: If not None, the subprocess's current directory will be changed to - |cwd| before it's executed. - shell: Whether to execute args as a shell command. - - Returns: - Captures and returns the command's stdout. - Prints the command's stderr to logger (which defaults to stdout). - """ - (_, output) = GetCmdStatusAndOutput(args, cwd, shell) - return output - - -def _ValidateAndLogCommand(args, cwd, shell): - if isinstance(args, basestring): - if not shell: - raise Exception('string args must be run with shell=True') - else: - if shell: - raise Exception('array args must be run with shell=False') - args = ' '.join(SingleQuote(c) for c in args) - if cwd is None: - cwd = '' - else: - cwd = ':' + cwd - logger.info('[host]%s> %s', cwd, args) - return args - - -def GetCmdStatusAndOutput(args, cwd=None, shell=False): - """Executes a subprocess and returns its exit code and output. - - Args: - args: A string or a sequence of program arguments. The program to execute is - the string or the first item in the args sequence. - cwd: If not None, the subprocess's current directory will be changed to - |cwd| before it's executed. - shell: Whether to execute args as a shell command. Must be True if args - is a string and False if args is a sequence. - - Returns: - The 2-tuple (exit code, output). - """ - status, stdout, stderr = GetCmdStatusOutputAndError( - args, cwd=cwd, shell=shell) - - if stderr: - logger.critical('STDERR: %s', stderr) - logger.debug('STDOUT: %s%s', stdout[:4096].rstrip(), - '<truncated>' if len(stdout) > 4096 else '') - return (status, stdout) - - -def GetCmdStatusOutputAndError(args, cwd=None, shell=False): - """Executes a subprocess and returns its exit code, output, and errors. - - Args: - args: A string or a sequence of program arguments. The program to execute is - the string or the first item in the args sequence. - cwd: If not None, the subprocess's current directory will be changed to - |cwd| before it's executed. - shell: Whether to execute args as a shell command. Must be True if args - is a string and False if args is a sequence. - - Returns: - The 2-tuple (exit code, output). - """ - _ValidateAndLogCommand(args, cwd, shell) - pipe = Popen(args, stdout=subprocess.PIPE, stderr=subprocess.PIPE, - shell=shell, cwd=cwd) - stdout, stderr = pipe.communicate() - return (pipe.returncode, stdout, stderr) - - -class TimeoutError(Exception): - """Module-specific timeout exception.""" - - def __init__(self, output=None): - super(TimeoutError, self).__init__() - self._output = output - - @property - def output(self): - return self._output - - -def _IterProcessStdout(process, iter_timeout=None, timeout=None, - buffer_size=4096, poll_interval=1): - """Iterate over a process's stdout. - - This is intentionally not public. - - Args: - process: The process in question. - iter_timeout: An optional length of time, in seconds, to wait in - between each iteration. If no output is received in the given - time, this generator will yield None. - timeout: An optional length of time, in seconds, during which - the process must finish. If it fails to do so, a TimeoutError - will be raised. - buffer_size: The maximum number of bytes to read (and thus yield) at once. - poll_interval: The length of time to wait in calls to `select.select`. - If iter_timeout is set, the remaining length of time in the iteration - may take precedence. - Raises: - TimeoutError: if timeout is set and the process does not complete. - Yields: - basestrings of data or None. - """ - - assert fcntl, 'fcntl module is required' - try: - # Enable non-blocking reads from the child's stdout. - child_fd = process.stdout.fileno() - fl = fcntl.fcntl(child_fd, fcntl.F_GETFL) - fcntl.fcntl(child_fd, fcntl.F_SETFL, fl | os.O_NONBLOCK) - - end_time = (time.time() + timeout) if timeout else None - iter_end_time = (time.time() + iter_timeout) if iter_timeout else None - - while True: - if end_time and time.time() > end_time: - raise TimeoutError() - if iter_end_time and time.time() > iter_end_time: - yield None - iter_end_time = time.time() + iter_timeout - - if iter_end_time: - iter_aware_poll_interval = min( - poll_interval, - max(0, iter_end_time - time.time())) - else: - iter_aware_poll_interval = poll_interval - - read_fds, _, _ = select.select( - [child_fd], [], [], iter_aware_poll_interval) - if child_fd in read_fds: - data = os.read(child_fd, buffer_size) - if not data: - break - yield data - if process.poll() is not None: - break - finally: - try: - if process.returncode is None: - # Make sure the process doesn't stick around if we fail with an - # exception. - process.kill() - except OSError: - pass - process.wait() - - -def GetCmdStatusAndOutputWithTimeout(args, timeout, cwd=None, shell=False, - logfile=None): - """Executes a subprocess with a timeout. - - Args: - args: List of arguments to the program, the program to execute is the first - element. - timeout: the timeout in seconds or None to wait forever. - cwd: If not None, the subprocess's current directory will be changed to - |cwd| before it's executed. - shell: Whether to execute args as a shell command. Must be True if args - is a string and False if args is a sequence. - logfile: Optional file-like object that will receive output from the - command as it is running. - - Returns: - The 2-tuple (exit code, output). - Raises: - TimeoutError on timeout. - """ - _ValidateAndLogCommand(args, cwd, shell) - output = StringIO.StringIO() - process = Popen(args, cwd=cwd, shell=shell, stdout=subprocess.PIPE, - stderr=subprocess.STDOUT) - try: - for data in _IterProcessStdout(process, timeout=timeout): - if logfile: - logfile.write(data) - output.write(data) - except TimeoutError: - raise TimeoutError(output.getvalue()) - - str_output = output.getvalue() - logger.debug('STDOUT+STDERR: %s%s', str_output[:4096].rstrip(), - '<truncated>' if len(str_output) > 4096 else '') - return process.returncode, str_output - - -def IterCmdOutputLines(args, iter_timeout=None, timeout=None, cwd=None, - shell=False, check_status=True): - """Executes a subprocess and continuously yields lines from its output. - - Args: - args: List of arguments to the program, the program to execute is the first - element. - iter_timeout: Timeout for each iteration, in seconds. - timeout: Timeout for the entire command, in seconds. - cwd: If not None, the subprocess's current directory will be changed to - |cwd| before it's executed. - shell: Whether to execute args as a shell command. Must be True if args - is a string and False if args is a sequence. - check_status: A boolean indicating whether to check the exit status of the - process after all output has been read. - Yields: - The output of the subprocess, line by line. - - Raises: - CalledProcessError if check_status is True and the process exited with a - non-zero exit status. - """ - cmd = _ValidateAndLogCommand(args, cwd, shell) - process = Popen(args, cwd=cwd, shell=shell, stdout=subprocess.PIPE, - stderr=subprocess.STDOUT) - return _IterCmdOutputLines( - process, cmd, iter_timeout=iter_timeout, timeout=timeout, - check_status=check_status) - -def _IterCmdOutputLines(process, cmd, iter_timeout=None, timeout=None, - check_status=True): - buffer_output = '' - - iter_end = None - cur_iter_timeout = None - if iter_timeout: - iter_end = time.time() + iter_timeout - cur_iter_timeout = iter_timeout - - for data in _IterProcessStdout(process, iter_timeout=cur_iter_timeout, - timeout=timeout): - if iter_timeout: - # Check whether the current iteration has timed out. - cur_iter_timeout = iter_end - time.time() - if data is None or cur_iter_timeout < 0: - yield None - iter_end = time.time() + iter_timeout - continue - else: - assert data is not None, ( - 'Iteration received no data despite no iter_timeout being set. ' - 'cmd: %s' % cmd) - - # Construct lines to yield from raw data. - buffer_output += data - has_incomplete_line = buffer_output[-1] not in '\r\n' - lines = buffer_output.splitlines() - buffer_output = lines.pop() if has_incomplete_line else '' - for line in lines: - yield line - if iter_timeout: - iter_end = time.time() + iter_timeout - - if buffer_output: - yield buffer_output - if check_status and process.returncode: - raise subprocess.CalledProcessError(process.returncode, cmd) |