bin/git_sha1_gen.py

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