bin/git_sha1_gen.py

   1 """
   2 Generate the contents of the git_sha1.h file.
   3 """
   4
   5
   6 import argparse
   7 import os
   8 import os.path
   9 import subprocess
  10 import sys
  11
  12
  13 def get_git_sha1():
  14     """Try to get the git SHA1 with git rev-parse."""
  15     git_dir = os.path.join(os.path.dirname(sys.argv[0]), '..', '.git')
  16     try:
  17         git_sha1 = subprocess.check_output([
  18             'git',
  19             '--git-dir=' + git_dir,
  20             'rev-parse',
  21             'HEAD',
  22         ], stderr=open(os.devnull, 'w')).decode("ascii")
  23     except:
  24         # don't print anything if it fails
  25         git_sha1 = ''
  26     return git_sha1
  27
  28 def write_if_different(contents):
  29     """
  30     Avoid touching the output file if it doesn't need modifications
  31     Useful to avoid triggering rebuilds when nothing has changed.
  32     """
  33     if os.path.isfile(args.output):
  34         with open(args.output, 'r') as file:
  35             if file.read() == contents:
  36                 return
  37     with open(args.output, 'w') as file:
  38         file.write(contents)
  39
  40 parser = argparse.ArgumentParser()
  41 parser.add_argument('--output', help='File to write the #define in',
  42                     required=True)
  43 args = parser.parse_args()
  44
  45 git_sha1 = os.environ.get('MESA_GIT_SHA1_OVERRIDE', get_git_sha1())[:10]
  46 if git_sha1:
  47     write_if_different('#define MESA_GIT_SHA1 " (git-' + git_sha1 + ')"')
  48 else:
  49     write_if_different('#define MESA_GIT_SHA1 ""')