Move webrtc/{tools => rtc_tools}

webrtc/tools/barcode_tools/helper_functions.py

-#!/usr/bin/env python
-# Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
-#
-# Use of this source code is governed by a BSD-style license
-# that can be found in the LICENSE file in the root of the source
-# tree. An additional intellectual property rights grant can be found
-# in the file PATENTS.  All contributing project authors may
-# be found in the AUTHORS file in the root of the source tree.
-
-import multiprocessing
-import os
-import subprocess
-import sys
-
-_DEFAULT_PADDING = 4
-
-
-class HelperError(Exception):
-  """Exception raised for errors in the helper."""
-  pass
-
-
-def ZeroPad(number, padding=_DEFAULT_PADDING):
-  """Converts an int into a zero padded string.
-
-  Args:
-    number(int): The number to convert.
-    padding(int): The number of chars in the output. Note that if you pass for
-      example number=23456 and padding=4, the output will still be '23456',
-      i.e. it will not be cropped. If you pass number=2 and padding=4, the
-      return value will be '0002'.
-  Return:
-    (string): The zero padded number converted to string.
-  """
-  return str(number).zfill(padding)
-
-
-def RunShellCommand(cmd_list, fail_msg=None):
-  """Executes a command.
-
-  Args:
-    cmd_list(list): Command list to execute.
-    fail_msg(string): Message describing the error in case the command fails.
-
-  Return:
-    (string): The standard output from running the command.
-
-  Raise:
-    HelperError: If command fails.
-  """
-  process = subprocess.Popen(cmd_list, stdout=subprocess.PIPE,
-                             stderr=subprocess.PIPE)
-  output, error = process.communicate()
-  if process.returncode != 0:
-    if fail_msg:
-      print >> sys.stderr, fail_msg
-    raise HelperError('Failed to run %s: command returned %d and printed '
-                      '%s and %s' % (' '.join(cmd_list), process.returncode,
-                                     output, error))
-  return output.strip()
-
-
-def PerformActionOnAllFiles(directory, file_pattern, file_extension,
-                            start_number, action, **kwargs):
-  """Function that performs a given action on all files matching a pattern.
-
-  It is assumed that the files are named file_patternxxxx.file_extension, where
-  xxxx are digits starting from start_number.
-
-  Args:
-    directory(string): The directory where the files live.
-    file_pattern(string): The name pattern of the files.
-    file_extension(string): The files' extension.
-    start_number(int): From where to start to count frames.
-    action(function): The action to be performed over the files. Must return
-        False if the action failed, True otherwise. It should take a file name
-        as the first argument and **kwargs as arguments. The function must be
-        possible to pickle, so it cannot be a bound function (for instance).
-
-  Return:
-    (bool): Whether performing the action over all files was successful or not.
-  """
-  file_prefix = os.path.join(directory, file_pattern)
-  file_number = start_number
-
-  process_pool = multiprocessing.Pool(processes=multiprocessing.cpu_count())
-  results = []
-  while True:
-    zero_padded_file_number = ZeroPad(file_number)
-    file_name = file_prefix + zero_padded_file_number + '.' + file_extension
-    if not os.path.isfile(file_name):
-      break
-    future = process_pool.apply_async(action, args=(file_name,), kwds=kwargs)
-    results.append(future)
-    file_number += 1
-
-  successful = True
-  for result in results:
-    if not result.get():
-      print "At least one action %s failed for files %sxxxx.%s." % (
-          action, file_pattern, file_extension)
-      successful = False
-
-  process_pool.close()
-  return successful