[PATCH v7 00/11] refs backend pre-vtable

This is another reroll of the pre-vtable part of the refs-backend patch series dt/refs-backend-pre-vtable. v6 [1] proved cumbersome because it conflicted messily with lf/ref-is-hidden-namespace [2]. The conflicts were partly due to the motion of code across files but, even worse, due to the change of order of function definitions between old and new files.

So I have heavily "optimized" this reroll for reviewability and to minimize conflicts with other work in the area. The only such work that I know of is lf/ref-is-hidden-namespace, which can now be merged with this series *without conflicts*.

Changes since v6:

* It doesn't move refs.c to the refs/ subdirectory, as v6 did.
  Instead, leave the shared code in the existing file, refs.c.

* Don't rename refs.c to refs/files-backend.c and then selectively
  move content back to refs.c. Instead, move content only once and
  only in one direction, namely from refs.c -> refs/files-backend.c
  (in patch 08/11). This is a giant commit but *it makes no other
  changes* so it should be easy to review. (The "--patience" option of
  "git diff" is quite helpful here. It was turned on when this patch
  series was generated.)

* Preserve the order of code during the move. Aside from a few lines
  of boilerplate, each of the following commands, when applied to
  commit 08, shows only lines being deleted:

    git diff --patience $commit^:refs.c $commit:refs.c
    git diff --patience $commit^:refs.c $commit:refs/files-backend.c

* To make all of the above possible, patches 01 through 06 do a little
  bit of preparatory code untangling. These commits have themselves
  been split up a bit to make them as "obviously correct" as possible.
  Patch 07 creates the new header file, refs/refs-internal.h, thereby
  increasing the visibility of some declarations.

* The final patches 09, 10, and 11 are not quite as "obviously
  correct" as the first eight, but I left them in to keep the logical
  contents of this patch series the same as v6. But these last three
  commits could just as well be postponed until the next tranche of
  patches if that helps speed the way of the first eight patches into
  master.

* I also fixed a commit message and fixed the implementation of the
  new verify_refname_available() function to return a negative number
  on error as documented (previously it returned 1 on error).

I've tried to attribute authorship of these changes as fairly as possible based on who initiated the corresponding changes. If anybody feels that I have appropriated his work or, conversely, put words into his mouth, just let me know and I would be happy to adjust the authorship.

It would be great to get this patch series (at least the first eight patches) reviewed and merged as soon as possible. Even though it no longer conflicts with lf/ref-is-hidden-namespace, it is still very prone to conflicting with any other work in the references code.

This patch series is also available on my GitHub fork [3] as branch "refs-backend-pre-vtable".

Michael

[1] http://thread.gmane.org/gmane.comp.version-control.git/280325/focus=280754 [2] http://article.gmane.org/gmane.comp.version-control.git/281004 [3] https://github.com/mhagger/git

David Turner (5):
  refs: make is_branch public
  copy_msg(): rename to copy_reflog_msg()
  initdb: make safe_create_dir public
  files_log_ref_write: new function
  refs: break out ref conflict checks

Michael Haggerty (4):
  pack_if_possible_fn(): use ref_type() instead of is_per_worktree_ref()
  refname_is_safe(): improve docstring
  refs/refs-internal.h: new header file
  refs: split filesystem-based refs code into a new file

Ronnie Sahlberg (2):
  verify_refname_available(): rename function
  verify_refname_available(): new function

 Makefile                       |    3 +-
 builtin/init-db.c              |   12 -
 cache.h                        |    8 +
 path.c                         |   12 +
 refs.c                         | 3709 +---------------------------------------
 refs.h                         |    2 +
 refs.c => refs/files-backend.c | 1287 +-------------
 refs/refs-internal.h           |  202 +++
 8 files changed, 315 insertions(+), 4920 deletions(-)
 copy refs.c => refs/files-backend.c (75%)
 create mode 100644 refs/refs-internal.h