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. We
  74     # follow symlinks so mach can be run even if cwd is outside the srcdir.
  75     return check_and_get_mach(os.path.dirname(os.path.realpath(__file__)))
  76
  77 def main(args):
  78     mach = get_mach()
  79     if not mach:
  80         print('Could not run mach: No mach source directory found.')
  81         sys.exit(1)
  82     sys.exit(mach.run(args))
  83
  84
  85 if __name__ == '__main__':
  86     if sys.platform == 'win32':
  87         # This is a complete hack to work around the fact that Windows
  88         # multiprocessing needs to import the original module (ie: this
  89         # file), but only works if it has a .py extension.
  90         #
  91         # We do this by a sort of two-level function interposing. The first
  92         # level interposes forking.get_command_line() with our version defined
  93         # in my_get_command_line(). Our version of get_command_line will
  94         # replace the command string with the contents of the fork_interpose()
  95         # function to be used in the subprocess.
  96         #
  97         # The subprocess then gets an interposed imp.find_module(), which we
  98         # hack up to find 'mach' without the .py extension, since we already
  99         # know where it is (it's us!). If we're not looking for 'mach', then
 100         # the original find_module will suffice.
 101         #
 102         # See also: http://bugs.python.org/issue19946
 103         # And: https://bugzilla.mozilla.org/show_bug.cgi?id=914563
 104         import inspect
 105         from multiprocessing import forking
 106         global orig_command_line
 107
 108         def fork_interpose():
 109             import imp
 110             import os
 111             import sys
 112             orig_find_module = imp.find_module
 113             def my_find_module(name, dirs):
 114                 if name == 'mach':
 115                     path = os.path.join(dirs[0], 'mach')
 116                     f = open(path)
 117                     return (f, path, ('', 'r', imp.PY_SOURCE))
 118                 return orig_find_module(name, dirs)
 119
 120             # Don't allow writing bytecode file for mach module.
 121             orig_load_module = imp.load_module
 122             def my_load_module(name, file, path, description):
 123                 # multiprocess.forking invokes imp.load_module manually and
 124                 # hard-codes the name __parents_main__ as the module name.
 125                 if name == '__parents_main__':
 126                     old_bytecode = sys.dont_write_bytecode
 127                     sys.dont_write_bytecode = True
 128                     try:
 129                         return orig_load_module(name, file, path, description)
 130                     finally:
 131                         sys.dont_write_bytecode = old_bytecode
 132
 133                 return orig_load_module(name, file, path, description)
 134
 135             imp.find_module = my_find_module
 136             imp.load_module = my_load_module
 137             from multiprocessing.forking import main; main()
 138
 139         def my_get_command_line():
 140             fork_code, lineno = inspect.getsourcelines(fork_interpose)
 141             # Remove the first line (for 'def fork_interpose():') and the three
 142             # levels of indentation (12 spaces).
 143             fork_string = ''.join(x[12:] for x in fork_code[1:])
 144             cmdline = orig_command_line()
 145             cmdline[2] = fork_string
 146             return cmdline
 147         orig_command_line = forking.get_command_line
 148         forking.get_command_line = my_get_command_line
 149
 150     main(sys.argv[1:])