Check revision and if no files modified (looking for svnversion equivalent)

Hi,

in my subversion software repository I use the 'svnversion' command to do both:

- get the last revision (e.g. r1001)
- check for modified files not yet checked in (e.g. r1001 M)

Both information is required for the application's build process (Makefiles):

- to display the version in the application
- to refuse to build a proper 'release' version if something
  was not checked in

Would there be a way to do both in git somehow?

 Felix