1#!/usr/bin/env python 2# Copyright (c) 2011 Google Inc. All rights reserved. 3# Use of this source code is governed by a BSD-style license that can be 4# found in the LICENSE file. 5 6"""These functions are executed via gyp-flock-tool when using the Makefile 7generator. Used on systems that don't have a built-in flock.""" 8 9import fcntl 10import os 11import struct 12import subprocess 13import sys 14 15 16def main(args): 17 executor = FlockTool() 18 executor.Dispatch(args) 19 20 21class FlockTool(object): 22 """This class emulates the 'flock' command.""" 23 def Dispatch(self, args): 24 """Dispatches a string command to a method.""" 25 if len(args) < 1: 26 raise Exception("Not enough arguments") 27 28 method = "Exec%s" % self._CommandifyName(args[0]) 29 getattr(self, method)(*args[1:]) 30 31 def _CommandifyName(self, name_string): 32 """Transforms a tool name like copy-info-plist to CopyInfoPlist""" 33 return name_string.title().replace('-', '') 34 35 def ExecFlock(self, lockfile, *cmd_list): 36 """Emulates the most basic behavior of Linux's flock(1).""" 37 # Rely on exception handling to report errors. 38 # Note that the stock python on SunOS has a bug 39 # where fcntl.flock(fd, LOCK_EX) always fails 40 # with EBADF, that's why we use this F_SETLK 41 # hack instead. 42 fd = os.open(lockfile, os.O_WRONLY|os.O_NOCTTY|os.O_CREAT, 0666) 43 op = struct.pack('hhllhhl', fcntl.F_WRLCK, 0, 0, 0, 0, 0, 0) 44 fcntl.fcntl(fd, fcntl.F_SETLK, op) 45 return subprocess.call(cmd_list) 46 47 48if __name__ == '__main__': 49 sys.exit(main(sys.argv[1:])) 50