[PATCH v2 00/13] Reference iterators

This is v2 of a patch series to implement iteration over references via iterators. Thanks to Ramsay, Eric, Junio, and David for their feedback about v1 [1]. I think I have addressed all of the points that were raised.

Changes from v1 -> v2:

* In "refs: introduce an iterator interface":

  * Fix some comments.

  * Remove a redundant call to `sort_ref_dir()`.

  * Rename the parameters to `overlay_ref_iterator` from `iter0` and
    `iter1` to `front` and `back`, and reverse their order.

  * Add a comment explaining why merge_ref_iterator_begin() can't do
    an is_empty_ref_iterator() optimization.

* In "dir_iterator: new API for iterating over a directory tree":

  * Fix some comments.

  * Add a warning if `lstat()` fails for a reason other than `ENOENT`.

This patch series applies on top of mh/split-under-lock. It can also be obtained from my GitHub repo [2] as branch "ref-iterators".

Michael

[1] http://thread.gmane.org/gmane.comp.version-control.git/295860 [2] https://github.com/mhagger/git

Michael Haggerty (13):
  refs: remove unnecessary "extern" keywords
  do_for_each_ref(): move docstring to the header file
  refs: use name "prefix" consistently
  delete_refs(): add a flags argument
  remote rm: handle symbolic refs correctly
  get_ref_cache(): only create an instance if there is a submodule
  entry_resolves_to_object(): rename function from
    ref_resolves_to_object()
  ref_resolves_to_object(): new function
  refs: introduce an iterator interface
  do_for_each_ref(): reimplement using reference iteration
  for_each_reflog(): don't abort for bad references
  dir_iterator: new API for iterating over a directory tree
  for_each_reflog(): reimplement using iterators

 Makefile             |   2 +
 builtin/fetch.c      |   2 +-
 builtin/remote.c     |   8 +-
 dir-iterator.c       | 185 +++++++++++++++
 dir-iterator.h       |  86 +++++++
 iterator.h           |  81 +++++++
 refs.c               |  20 ++
 refs.h               | 139 +++++++-----
 refs/files-backend.c | 629 +++++++++++++++++++++++++++++++--------------------
 refs/iterator.c      | 384 +++++++++++++++++++++++++++++++
 refs/refs-internal.h | 226 +++++++++++++++++-
 11 files changed, 1440 insertions(+), 322 deletions(-)
 create mode 100644 dir-iterator.c
 create mode 100644 dir-iterator.h
 create mode 100644 iterator.h
 create mode 100644 refs/iterator.c