old_contents: #!/usr/bin/env python
  #
  # Copyright (c) 2006 Verdens Gang AS
  # Copyright (c) 2006-2015 Varnish Software AS
  # All rights reserved.
  #
  # Author: Poul-Henning Kamp <phk@phk.freebsd.dk>
  #
  # Redistribution and use in source and binary forms, with or without
  # modification, are permitted provided that the following conditions
  # are met:
  # 1. Redistributions of source code must retain the above copyright
  #    notice, this list of conditions and the following disclaimer.
  # 2. Redistributions in binary form must reproduce the above copyright
  #    notice, this list of conditions and the following disclaimer in the
  #    documentation and/or other materials provided with the distribution.
  #
  # THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  # ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  # ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
  # FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  # DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  # OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  # HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  # LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  # OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  # SUCH DAMAGE.
  #
  # Generate vcs_version.h vmod_abi.h
  
  from __future__ import print_function
  
  import subprocess
  import collections
  import os
  import sys
  
  srcroot = "../.."
  buildroot = "../.."
  if len(sys.argv) == 3:
  	srcroot = sys.argv[1]
  	buildroot = sys.argv[2]
  elif len(sys.argv) != 1:
  	print("Two arguments or none")
  	exit(2)
  
  #######################################################################
  def file_header(fo):
  	fo.write("""/*
   * NB:  This file is machine generated, DO NOT EDIT!
   *
   * Edit and run lib/libvcc/generate.py instead.
   */
  
  """)
  
  #######################################################################
  
  if os.path.isdir(os.path.join(srcroot, ".git")):
  	v = subprocess.check_output([
  		"git --git-dir=" + os.path.join(srcroot, ".git") +
  		" show -s --pretty=format:%H"
  	], shell=True, universal_newlines=True)
  	v = v.strip()
  else:
  	v = "NOGIT"
  
  vcsfn = os.path.join(srcroot, "include", "vcs_version.h")
  
  try:
  	i = open(vcsfn).readline()
  except IOError:
  	i = ""
  
  ident = "/* " + v + " */\n"
  
  if i != ident:
  	fo = open(vcsfn, "w")
  	fo.write(ident)
  	file_header(fo)
  	fo.write('#define VCS_Version "%s"\n' % v)
  	fo.close()
  
  	for i in open(os.path.join(buildroot, "Makefile")):
  		if i[:14] == "PACKAGE_STRING":
  			break
  	i = i.split("=")[1].strip()
  
  	fo = open(os.path.join(srcroot, "include", "vmod_abi.h"), "w")
  	file_header(fo)
  	fo.write('#define VMOD_ABI_Version "%s %s"\n' % (i, v))
  	fo.close()
  
new_contents: #!/usr/bin/env python
  #
  # Copyright (c) 2006 Verdens Gang AS
  # Copyright (c) 2006-2015 Varnish Software AS
  # All rights reserved.
  #
  # Author: Poul-Henning Kamp <phk@phk.freebsd.dk>
  #
  # Redistribution and use in source and binary forms, with or without
  # modification, are permitted provided that the following conditions
  # are met:
  # 1. Redistributions of source code must retain the above copyright
  #    notice, this list of conditions and the following disclaimer.
  # 2. Redistributions in binary form must reproduce the above copyright
  #    notice, this list of conditions and the following disclaimer in the
  #    documentation and/or other materials provided with the distribution.
  #
  # THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  # ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  # ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
  # FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  # DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  # OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  # HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  # LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  # OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  # SUCH DAMAGE.
  #
  # Generate vcs_version.h vmod_abi.h
  
  from __future__ import print_function
  
  import subprocess
  import collections
  import os
  import sys
  
  srcroot = "../.."
  buildroot = "../.."
  if len(sys.argv) == 3:
  	srcroot = sys.argv[1]
  	buildroot = sys.argv[2]
  elif len(sys.argv) != 1:
  	print("Two arguments or none")
  	exit(2)
  
  #######################################################################
  def file_header(fo):
  	fo.write("""/*
   * NB:  This file is machine generated, DO NOT EDIT!
   *
   * Edit and run include/generate.py instead.
   */
  
  """)
  
  #######################################################################
  
  
  v = subprocess.check_output([
      "git --git-dir=%s rev-parse HEAD 2>/dev/null || echo NOGIT" %
      (os.path.join(srcroot, ".git"))
      ], shell=True, universal_newlines=True).strip()
  
  vcsfn = os.path.join(srcroot, "include", "vcs_version.h")
  
  try:
  	i = open(vcsfn).readline()
  except IOError:
  	i = ""
  
  ident = "/* " + v + " */\n"
  
  if i != ident:
  	fo = open(vcsfn, "w")
  	fo.write(ident)
  	file_header(fo)
  	fo.write('#define VCS_Version "%s"\n' % v)
  	fo.close()
  
  	for i in open(os.path.join(buildroot, "Makefile")):
  		if i[:14] == "PACKAGE_STRING":
  			break
  	i = i.split("=")[1].strip()
  
  	fo = open(os.path.join(srcroot, "include", "vmod_abi.h"), "w")
  	file_header(fo)
  	fo.write('#define VMOD_ABI_Version "%s %s"\n' % (i, v))
  	fo.close()
  
subject: Simplify include/generate.py