mach

   1 #!/bin/sh
   2 # This Source Code Form is subject to the terms of the Mozilla Public
   3 # License, v. 2.0. If a copy of the MPL was not distributed with this
   4 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
   5
   6 # The beginning of this script is both valid shell and valid python,
   7 # such that the script starts with the shell and is reexecuted with
   8 # the right python.
   9 '''which' python2.7 > /dev/null && exec python2.7 "$0" "$@" || exec python "$0" "$@"
  10 '''
  11
  12 from __future__ import print_function, unicode_literals
  13
  14 import os
  15 import sys
  16
  17 def ancestors(path):
  18     while path:
  19         yield path
  20         (path, child) = os.path.split(path)
  21         if child == "":
  22             break
  23
  24 def load_mach(dir_path, mach_path):
  25     import imp
  26     with open(mach_path, 'r') as fh:
  27         imp.load_module('mach_bootstrap', fh, mach_path,
  28                         ('.py', 'r', imp.PY_SOURCE))
  29     import mach_bootstrap
  30     return mach_bootstrap.bootstrap(dir_path)
  31
  32
  33 def check_and_get_mach(dir_path):
  34     bootstrap_paths = (
  35         'build/mach_bootstrap.py',
  36         # test package bootstrap
  37         'tools/mach_bootstrap.py',
  38     )
  39     for bootstrap_path in bootstrap_paths:
  40         mach_path = os.path.join(dir_path, bootstrap_path)
  41         if os.path.isfile(mach_path):
  42             return load_mach(dir_path, mach_path)
  43     return None
  44
  45
  46 def get_mach():
  47     # Check whether the current directory is within a mach src or obj dir.
  48     for dir_path in ancestors(os.getcwd()):
  49         # If we find a "mozinfo.json" file, we are in the objdir.
  50         mozinfo_path = os.path.join(dir_path, 'mozinfo.json')
  51         if os.path.isfile(mozinfo_path):
  52             import json
  53             info = json.load(open(mozinfo_path))
  54             if 'mozconfig' in info and 'MOZCONFIG' not in os.environ:
  55                 # If the MOZCONFIG environment variable is not already set, set it
  56                 # to the value from mozinfo.json.  This will tell the build system
  57                 # to look for a config file at the path in $MOZCONFIG rather than
  58                 # its default locations.
  59                 #
  60                 # Note: subprocess requires native strings in os.environ on Windows
  61                 os.environ[b'MOZCONFIG'] = str(info['mozconfig'])
  62
  63             if 'topsrcdir' in info:
  64                 # Continue searching for mach_bootstrap in the source directory.
  65                 dir_path = info['topsrcdir']
  66
  67         mach = check_and_get_mach(dir_path)
  68         if mach:
  69             return mach
  70
  71     # If we didn't find a source path by scanning for a mozinfo.json, check
  72     # whether the directory containing this script is a source directory.
  73     return check_and_get_mach(os.path.dirname(__file__))
  74
  75 def main(args):
  76     mach = get_mach()
  77     if not mach:
  78         print('Could not run mach: No mach source directory found.')
  79         sys.exit(1)
  80     sys.exit(mach.run(args))
  81
  82
  83 if __name__ == '__main__':
  84     if sys.platform == 'win32':
  85         # This is a complete hack to work around the fact that Windows
  86         # multiprocessing needs to import the original module (ie: this
  87         # file), but only works if it has a .py extension.
  88         #
  89         # We do this by a sort of two-level function interposing. The first
  90         # level interposes forking.get_command_line() with our version defined
  91         # in my_get_command_line(). Our version of get_command_line will
  92         # replace the command string with the contents of the fork_interpose()
  93         # function to be used in the subprocess.
  94         #
  95         # The subprocess then gets an interposed imp.find_module(), which we
  96         # hack up to find 'mach' without the .py extension, since we already
  97         # know where it is (it's us!). If we're not looking for 'mach', then
  98         # the original find_module will suffice.
  99         #
 100         # See also: http://bugs.python.org/issue19946
 101         # And: https://bugzilla.mozilla.org/show_bug.cgi?id=914563
 102         import inspect
 103         from multiprocessing import forking
 104         global orig_command_line
 105
 106         def fork_interpose():
 107             import imp
 108             import os
 109             import sys
 110             orig_find_module = imp.find_module
 111             def my_find_module(name, dirs):
 112                 if name == 'mach':
 113                     path = os.path.join(dirs[0], 'mach')
 114                     f = open(path)
 115                     return (f, path, ('', 'r', imp.PY_SOURCE))
 116                 return orig_find_module(name, dirs)
 117
 118             # Don't allow writing bytecode file for mach module.
 119             orig_load_module = imp.load_module
 120             def my_load_module(name, file, path, description):
 121                 # multiprocess.forking invokes imp.load_module manually and
 122                 # hard-codes the name __parents_main__ as the module name.
 123                 if name == '__parents_main__':
 124                     old_bytecode = sys.dont_write_bytecode
 125                     sys.dont_write_bytecode = True
 126                     try:
 127                         return orig_load_module(name, file, path, description)
 128                     finally:
 129                         sys.dont_write_bytecode = old_bytecode
 130
 131                 return orig_load_module(name, file, path, description)
 132
 133             imp.find_module = my_find_module
 134             imp.load_module = my_load_module
 135             from multiprocessing.forking import main; main()
 136
 137         def my_get_command_line():
 138             fork_code, lineno = inspect.getsourcelines(fork_interpose)
 139             # Remove the first line (for 'def fork_interpose():') and the three
 140             # levels of indentation (12 spaces).
 141             fork_string = ''.join(x[12:] for x in fork_code[1:])
 142             cmdline = orig_command_line()
 143             cmdline[2] = fork_string
 144             return cmdline
 145         orig_command_line = forking.get_command_line
 146         forking.get_command_line = my_get_command_line
 147
 148     main(sys.argv[1:])