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 "config.status" and "mozinfo.json" file, we are in the objdir.
  50         config_status_path = os.path.join(dir_path, 'config.status')
  51         mozinfo_path = os.path.join(dir_path, 'mozinfo.json')
  52         if os.path.isfile(config_status_path) and os.path.isfile(mozinfo_path):
  53             import json
  54             info = json.load(open(mozinfo_path))
  55             if 'mozconfig' in info and 'MOZCONFIG' not in os.environ:
  56                 # If the MOZCONFIG environment variable is not already set, set it
  57                 # to the value from mozinfo.json.  This will tell the build system
  58                 # to look for a config file at the path in $MOZCONFIG rather than
  59                 # its default locations.
  60                 #
  61                 # Note: subprocess requires native strings in os.environ on Windows
  62                 os.environ[b'MOZCONFIG'] = str(info['mozconfig'])
  63
  64             if 'topsrcdir' in info:
  65                 # Continue searching for mach_bootstrap in the source directory.
  66                 dir_path = info['topsrcdir']
  67
  68         mach = check_and_get_mach(dir_path)
  69         if mach:
  70             return mach
  71
  72     # If we didn't find a source path by scanning for a mozinfo.json, check
  73     # whether the directory containing this script is a source directory.
  74     return check_and_get_mach(os.path.dirname(__file__))
  75
  76 def main(args):
  77     mach = get_mach()
  78     if not mach:
  79         print('Could not run mach: No mach source directory found.')
  80         sys.exit(1)
  81     sys.exit(mach.run(args))
  82
  83
  84 if __name__ == '__main__':
  85     if sys.platform == 'win32':
  86         # This is a complete hack to work around the fact that Windows
  87         # multiprocessing needs to import the original module (ie: this
  88         # file), but only works if it has a .py extension.
  89         #
  90         # We do this by a sort of two-level function interposing. The first
  91         # level interposes forking.get_command_line() with our version defined
  92         # in my_get_command_line(). Our version of get_command_line will
  93         # replace the command string with the contents of the fork_interpose()
  94         # function to be used in the subprocess.
  95         #
  96         # The subprocess then gets an interposed imp.find_module(), which we
  97         # hack up to find 'mach' without the .py extension, since we already
  98         # know where it is (it's us!). If we're not looking for 'mach', then
  99         # the original find_module will suffice.
 100         #
 101         # See also: http://bugs.python.org/issue19946
 102         # And: https://bugzilla.mozilla.org/show_bug.cgi?id=914563
 103         import inspect
 104         from multiprocessing import forking
 105         global orig_command_line
 106
 107         def fork_interpose():
 108             import imp
 109             import os
 110             import sys
 111             orig_find_module = imp.find_module
 112             def my_find_module(name, dirs):
 113                 if name == 'mach':
 114                     path = os.path.join(dirs[0], 'mach')
 115                     f = open(path)
 116                     return (f, path, ('', 'r', imp.PY_SOURCE))
 117                 return orig_find_module(name, dirs)
 118
 119             # Don't allow writing bytecode file for mach module.
 120             orig_load_module = imp.load_module
 121             def my_load_module(name, file, path, description):
 122                 # multiprocess.forking invokes imp.load_module manually and
 123                 # hard-codes the name __parents_main__ as the module name.
 124                 if name == '__parents_main__':
 125                     old_bytecode = sys.dont_write_bytecode
 126                     sys.dont_write_bytecode = True
 127                     try:
 128                         return orig_load_module(name, file, path, description)
 129                     finally:
 130                         sys.dont_write_bytecode = old_bytecode
 131
 132                 return orig_load_module(name, file, path, description)
 133
 134             imp.find_module = my_find_module
 135             imp.load_module = my_load_module
 136             from multiprocessing.forking import main; main()
 137
 138         def my_get_command_line():
 139             fork_code, lineno = inspect.getsourcelines(fork_interpose)
 140             # Remove the first line (for 'def fork_interpose():') and the three
 141             # levels of indentation (12 spaces).
 142             fork_string = ''.join(x[12:] for x in fork_code[1:])
 143             cmdline = orig_command_line()
 144             cmdline[2] = fork_string
 145             return cmdline
 146         orig_command_line = forking.get_command_line
 147         forking.get_command_line = my_get_command_line
 148
 149     main(sys.argv[1:])