[PATCH 00/10] [RFC] pickaxe for function names

This series introduces a --function-name=<pattern> option for git-log, intended to search for commits which touch a function matching a certain pattern (a feature we've seen requested and are interested in using ourselves).

This is our first attempt to patch git; we've tried to observe and follow the community standards, but we would greatly appreciate feedback. We've been working on this for a few weeks, and I just noticed that René Scharfe has done conflicing (and better) refactoring work in diffcore-pickaxe.c a few days ago. We'd be happy to rebase our changes and resolve the conflicts once René's patches are committed to master, but we thought we may as well ask for comments on the version we have working now.

Thanks for your time!

  .gitattributes: specify the language used
  diffcore-pickaxe.c: refactor regex compilation
  diffcore-pickaxe.c: Refactor pickaxe_fn signature
  diff.c/diff.h: expose userdiff_funcname
  diffcore-pickaxe.c: set up funcname pattern
  log: --function-name pickaxe
  xdiff: add XDL_EMIT_MOREFUNCNAMES to try harder
  xdiff: add XDL_EMIT_MOREHUNKHEADS to split hunks
  t4213: test --function-name option
  Documentation: Document --function-name usage

 .gitattributes                 |   2 +-
 Documentation/diff-options.txt |   9 +++
 Documentation/gitdiffcore.txt  |  17 ++++-
 builtin/log.c                  |   2 +-
 diff.c                         |  13 +++-
 diff.h                         |   3 +
 diffcore-pickaxe.c             | 162 +++++++++++++++++++++++++++++++++++-----------
 revision.c                     |   3 +-
 t/t4213-log-function-name.sh   |  73 +++++++++++++++++++++
 xdiff/xdiff.h                  |   2 +
 xdiff/xdiffi.c                 |   2 +-
 xdiff/xemit.c                  |  99 ++++++++++++++++++++++------
 xdiff/xemit.h                  |   4 +-
 13 files changed, 323 insertions(+), 68 deletions(-)