python: Backport argparse to older platforms.

Argparse has some convenient advantages over optparse including the
ability to handle optional arguments to flags.  It also supports
parsing arguments as well as options.

This patch copies argparse.py from Python 2.7 into a newly created
compat directory.  It made some very minor syntactic updates in the
process.  Platforms which have a Python version too old to include
argparse by default will have this compat version installed as a
workaround.

COPYING

@@ -25,3 +25,55 @@ basis.  Refer to each file for details.
 Files lib/sflow*.[ch] are licensed under the terms of the InMon sFlow
 licence that is available at:
         http://www.inmon.com/technology/sflowlicense.txt
+
+Files under python/compat are licensed under the Python Software
+Foundation License, version 2:
+
+   PYTHON SOFTWARE FOUNDATION LICENSE VERSION 2
+   --------------------------------------------
+
+   1. This LICENSE AGREEMENT is between the Python Software Foundation
+   ("PSF"), and the Individual or Organization ("Licensee") accessing and
+   otherwise using this software ("Python") in source or binary form and
+   its associated documentation.
+
+   2. Subject to the terms and conditions of this License Agreement, PSF
+   hereby grants Licensee a nonexclusive, royalty-free, world-wide
+   license to reproduce, analyze, test, perform and/or display publicly,
+   prepare derivative works, distribute, and otherwise use Python
+   alone or in any derivative version, provided, however, that PSF's
+   License Agreement and PSF's notice of copyright, i.e., "Copyright (c)
+   2001, 2002, 2003, 2004, 2005, 2006, 2007 Python Software Foundation;
+   All Rights Reserved" are retained in Python alone or in any derivative
+   version prepared by Licensee.
+
+   3. In the event Licensee prepares a derivative work that is based on
+   or incorporates Python or any part thereof, and wants to make
+   the derivative work available to others as provided herein, then
+   Licensee hereby agrees to include in any such work a brief summary of
+   the changes made to Python.
+
+   4. PSF is making Python available to Licensee on an "AS IS"
+   basis.  PSF MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR
+   IMPLIED.  BY WAY OF EXAMPLE, BUT NOT LIMITATION, PSF MAKES NO AND
+   DISCLAIMS ANY REPRESENTATION OR WARRANTY OF MERCHANTABILITY OR FITNESS
+   FOR ANY PARTICULAR PURPOSE OR THAT THE USE OF PYTHON WILL NOT
+   INFRINGE ANY THIRD PARTY RIGHTS.
+
+   5. PSF SHALL NOT BE LIABLE TO LICENSEE OR ANY OTHER USERS OF PYTHON
+   FOR ANY INCIDENTAL, SPECIAL, OR CONSEQUENTIAL DAMAGES OR LOSS AS
+   A RESULT OF MODIFYING, DISTRIBUTING, OR OTHERWISE USING PYTHON,
+   OR ANY DERIVATIVE THEREOF, EVEN IF ADVISED OF THE POSSIBILITY THEREOF.
+
+   6. This License Agreement will automatically terminate upon a material
+   breach of its terms and conditions.
+
+   7. Nothing in this License Agreement shall be deemed to create any
+   relationship of agency, partnership, or joint venture between PSF and
+   Licensee.  This License Agreement does not grant permission to use PSF
+   trademarks or trade name in a trademark sense to endorse or promote
+   products or services of Licensee, or any third party.
+
+   8. By copying, installing or otherwise using Python, Licensee
+   agrees to be bound by the terms and conditions of this License
+   Agreement.

Makefile.am

@@ -181,3 +181,4 @@ include ovsdb/automake.mk
 include rhel/automake.mk
 include xenserver/automake.mk
 include python/ovs/automake.mk
+include python/compat/automake.mk

debian/control

@@ -33,7 +33,7 @@ Description: Open vSwitch datapath module source - DKMS version
 
 Package: openvswitch-common
 Architecture: linux-any
-Depends: ${shlibs:Depends}, openssl, ${misc:Depends}, python
+Depends: ${shlibs:Depends}, openssl, ${misc:Depends}, python, python-argparse
 Suggests: ethtool
 Description: Open vSwitch common components
  openvswitch-common provides components required by both openvswitch-switch

debian/copyright.in

@@ -81,13 +81,14 @@ License:
   On Debian systems, the complete text of the Apache License version 2.0
   can be found in '/usr/share/common-licenses/Apache-2.0'.
 
-* The following component is licenced under the
+* The following components are licenced under the
   Python Software Foundation License Version 2.
 
-	xenserver/uuid.py
+	python/compat/uuid.py
+	python/compat/argparse.py
 
-	* This component is only distributed in the source package.
-	  It does not appear in any binary packages.
+	* These components are only distributed in the source package.
+	  They do not appear in any binary packages.
 
    PYTHON SOFTWARE FOUNDATION LICENSE VERSION 2
    --------------------------------------------