1 files changed, 49 insertions, 0 deletions
diff --git a/deps/gyp/pylib/gyp/flock_tool.py b/deps/gyp/pylib/gyp/flock_tool.py
new file mode 100755
index 0000000000..3e7efff26e
--- /dev/null
+++ b/deps/gyp/pylib/gyp/flock_tool.py
@@ -0,0 +1,49 @@
+#!/usr/bin/env python
+# Copyright (c) 2011 Google Inc. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""These functions are executed via gyp-flock-tool when using the Makefile
+generator.  Used on systems that don't have a built-in flock."""
+
+import fcntl
+import os
+import struct
+import subprocess
+import sys
+
+
+def main(args):
+  executor = FlockTool()
+  executor.Dispatch(args)
+
+
+class FlockTool(object):
+  """This class emulates the 'flock' command."""
+  def Dispatch(self, args):
+    """Dispatches a string command to a method."""
+    if len(args) < 1:
+      raise Exception("Not enough arguments")
+
+    method = "Exec%s" % self._CommandifyName(args[0])
+    getattr(self, method)(*args[1:])
+
+  def _CommandifyName(self, name_string):
+    """Transforms a tool name like copy-info-plist to CopyInfoPlist"""
+    return name_string.title().replace('-', '')
+
+  def ExecFlock(self, lockfile, *cmd_list):
+    """Emulates the most basic behavior of Linux's flock(1)."""
+    # Rely on exception handling to report errors.
+    # Note that the stock python on SunOS has a bug
+    # where fcntl.flock(fd, LOCK_EX) always fails
+    # with EBADF, that's why we use this F_SETLK
+    # hack instead.
+    fd = os.open(lockfile, os.O_WRONLY|os.O_NOCTTY|os.O_CREAT, 0666)
+    op = struct.pack('hhllhhl', fcntl.F_WRLCK, 0, 0, 0, 0, 0, 0)
+    fcntl.fcntl(fd, fcntl.F_SETLK, op)
+    return subprocess.call(cmd_list)
+
+
+if __name__ == '__main__':
+  sys.exit(main(sys.argv[1:]))