1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/media/webrtc/trunk/build/android/pylib/flag_changer.py Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,144 @@
1.4 +# Copyright (c) 2012 The Chromium Authors. All rights reserved.
1.5 +# Use of this source code is governed by a BSD-style license that can be
1.6 +# found in the LICENSE file.
1.7 +
1.8 +import constants
1.9 +import traceback
1.10 +import warnings
1.11 +
1.12 +
1.13 +# Location where chrome reads command line flags from
1.14 +CHROME_COMMAND_FILE = constants.TEST_EXECUTABLE_DIR + '/chrome-command-line'
1.15 +
1.16 +class FlagChanger(object):
1.17 + """Changes the flags Chrome runs with.
1.18 +
1.19 + There are two different use cases for this file:
1.20 + * Flags are permanently set by calling Set().
1.21 + * Flags can be temporarily set for a particular set of unit tests. These
1.22 + tests should call Restore() to revert the flags to their original state
1.23 + once the tests have completed.
1.24 + """
1.25 +
1.26 + def __init__(self, android_cmd):
1.27 + self._android_cmd = android_cmd
1.28 +
1.29 + # Save the original flags.
1.30 + self._orig_line = self._android_cmd.GetFileContents(CHROME_COMMAND_FILE)
1.31 + if self._orig_line:
1.32 + self._orig_line = self._orig_line[0].strip()
1.33 +
1.34 + # Parse out the flags into a list to facilitate adding and removing flags.
1.35 + self._current_flags = self._TokenizeFlags(self._orig_line)
1.36 +
1.37 + def Get(self):
1.38 + """Returns list of current flags."""
1.39 + return self._current_flags
1.40 +
1.41 + def Set(self, flags):
1.42 + """Replaces all flags on the current command line with the flags given.
1.43 +
1.44 + Args:
1.45 + flags: A list of flags to set, eg. ['--single-process'].
1.46 + """
1.47 + if flags:
1.48 + assert flags[0] != 'chrome'
1.49 +
1.50 + self._current_flags = flags
1.51 + self._UpdateCommandLineFile()
1.52 +
1.53 + def AddFlags(self, flags):
1.54 + """Appends flags to the command line if they aren't already there.
1.55 +
1.56 + Args:
1.57 + flags: A list of flags to add on, eg. ['--single-process'].
1.58 + """
1.59 + if flags:
1.60 + assert flags[0] != 'chrome'
1.61 +
1.62 + # Avoid appending flags that are already present.
1.63 + for flag in flags:
1.64 + if flag not in self._current_flags:
1.65 + self._current_flags.append(flag)
1.66 + self._UpdateCommandLineFile()
1.67 +
1.68 + def RemoveFlags(self, flags):
1.69 + """Removes flags from the command line, if they exist.
1.70 +
1.71 + Args:
1.72 + flags: A list of flags to remove, eg. ['--single-process']. Note that we
1.73 + expect a complete match when removing flags; if you want to remove
1.74 + a switch with a value, you must use the exact string used to add
1.75 + it in the first place.
1.76 + """
1.77 + if flags:
1.78 + assert flags[0] != 'chrome'
1.79 +
1.80 + for flag in flags:
1.81 + if flag in self._current_flags:
1.82 + self._current_flags.remove(flag)
1.83 + self._UpdateCommandLineFile()
1.84 +
1.85 + def Restore(self):
1.86 + """Restores the flags to their original state."""
1.87 + self._current_flags = self._TokenizeFlags(self._orig_line)
1.88 + self._UpdateCommandLineFile()
1.89 +
1.90 + def _UpdateCommandLineFile(self):
1.91 + """Writes out the command line to the file, or removes it if empty."""
1.92 + print "Current flags: ", self._current_flags
1.93 +
1.94 + if self._current_flags:
1.95 + self._android_cmd.SetFileContents(CHROME_COMMAND_FILE,
1.96 + 'chrome ' +
1.97 + ' '.join(self._current_flags))
1.98 + else:
1.99 + self._android_cmd.RunShellCommand('rm ' + CHROME_COMMAND_FILE)
1.100 +
1.101 + def _TokenizeFlags(self, line):
1.102 + """Changes the string containing the command line into a list of flags.
1.103 +
1.104 + Follows similar logic to CommandLine.java::tokenizeQuotedArguments:
1.105 + * Flags are split using whitespace, unless the whitespace is within a
1.106 + pair of quotation marks.
1.107 + * Unlike the Java version, we keep the quotation marks around switch
1.108 + values since we need them to re-create the file when new flags are
1.109 + appended.
1.110 +
1.111 + Args:
1.112 + line: A string containing the entire command line. The first token is
1.113 + assumed to be the program name.
1.114 + """
1.115 + if not line:
1.116 + return []
1.117 +
1.118 + tokenized_flags = []
1.119 + current_flag = ""
1.120 + within_quotations = False
1.121 +
1.122 + # Move through the string character by character and build up each flag
1.123 + # along the way.
1.124 + for c in line.strip():
1.125 + if c is '"':
1.126 + if len(current_flag) > 0 and current_flag[-1] == '\\':
1.127 + # Last char was a backslash; pop it, and treat this " as a literal.
1.128 + current_flag = current_flag[0:-1] + '"'
1.129 + else:
1.130 + within_quotations = not within_quotations
1.131 + current_flag += c
1.132 + elif not within_quotations and (c is ' ' or c is '\t'):
1.133 + if current_flag is not "":
1.134 + tokenized_flags.append(current_flag)
1.135 + current_flag = ""
1.136 + else:
1.137 + current_flag += c
1.138 +
1.139 + # Tack on the last flag.
1.140 + if not current_flag:
1.141 + if within_quotations:
1.142 + warnings.warn("Unterminated quoted string: " + current_flag)
1.143 + else:
1.144 + tokenized_flags.append(current_flag)
1.145 +
1.146 + # Return everything but the program name.
1.147 + return tokenized_flags[1:]
