There was a need to get per user contributions in a project last year. That project was versioned using Subversion (svn). At last we came up with the following script, which surely is not fool proof, provides an over all per user contribution. Here it's: However, I left it to you to improve further; who knows the unmodified version might be good enough for you.
To share bits of knowledge, experiences, lessons & fun stuff from my life.