apply: plug the three-way merge logic in

When a patch does not apply to what we have, but we know the preimage the
patch was made against, we apply the patch to the preimage to compute what
the patch author wanted the result to look like, and attempt a three-way
merge between the result and our version, using the intended preimage as
the base version.

When we are applying the patch using the index, we would additionally need
to add the object names of these three blobs involved in the merge, which
is not yet done in this step, but we add a field to "struct patch" so that
later write-out step can use it.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
apply: register conflicted stages to the index

Now we have all the necessary logic to fall back on three-way merge when
the patch does not cleanly apply, insert the conflicted entries to the
index as appropriate.  This obviously triggers only when the "--index"
option is used.

When we fall back to three-way merge and some of the merges fail, just
like the case where the "--reject" option was specified and we had to
write some "*.rej" files out for unapplicable patches, exit the command
with non-zero status without showing the diffstat and summary.  Otherwise
they would make the list of problematic paths scroll off the display.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
apply: allow rerere() upon --3way results

Signed-off-by: Junio C Hamano <gitster@pobox.com>
apply: document --3way option

Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merge branch 'nd/i18n-parseopt' into jch

Text from "git cmd --help" are getting prepared for i18n.

By Nguyễn Thái Ngọc Duy
* nd/i18n-parseopt:
  i18n: apply: mark parseopt strings for translation
  i18n: parseopt: lookup help and argument translations when showing usage
Merge branch 'rs/xdiff-lose-emit-func' into jch

Simplifies the interface between the implementation of "blame" and
underlying xdiff engine, and removes a lot of unused or unnecessary code
from the latter.

By René Scharfe (6) and Ramsay Jones (1)
* rs/xdiff-lose-emit-func:
  builtin/blame.c: Fix a "Using plain integer as NULL pointer" warning
  xdiff: remove unused functions
  xdiff: remove emit_func() and xdi_diff_hunks()
  blame: factor out helper for calling xdi_diff()
  blame: use hunk_func(), part 2
  blame: use hunk_func(), part 1
  xdiff: add hunk_func()
Merge branch 'ld/git-p4-tags-and-labels' into jch

By Luke Diamand
* ld/git-p4-tags-and-labels:
  git p4: fix bug when enabling tag import/export via config variables
  git p4: fix bug when verbose enabled with tag export
  git p4: add test for tag import/export enabled via config
Merge branch 'fc/git-complete-helper' into jch

By Felipe Contreras
* fc/git-complete-helper:
  completion: add new __git_complete helper
Merge branch 'nl/http-proxy-more' into pu

I queued only the later two patches from this series, even though they do
not make much sense without the first one that seems to need a bit more
work, so that we won't forget.

By Jeff King (1) and Nelson Benitez Leon (1)
* nl/http-proxy-more:
  http: rename HTTP_REAUTH to HTTP_AUTH_RETRY
  http: Avoid limit of retrying request only twice
Merge branch 'mm/push-default-switch-warning' into pu

Will squash the two, but this has to wait for a few release cycles.

By Junio C Hamano (1) and Matthieu Moy (1)
* mm/push-default-switch-warning:
  t5541: warning message is given even with --quiet
  push: start warning upcoming default change for push.default
Merge branch 'jc/split-blob' into pu

Not ready.

I finished the streaming checkout codepath, but as explained in
127b177 (bulk-checkin: support chunked-object encoding, 2011-11-30),
these are still early steps of a long and painful journey. At least
pack-objects and fsck need to learn the new encoding for the series
to be usable locally, and then index-pack/unpack-objects needs to
learn it to be used remotely.

Given that I heard a lot of noise that people want large files, and
that I was asked by somebody at GitTogether'11 privately for an
advice on how to pay developers (not me) to help adding necessary
support, I am somewhat dissapointed that the original patch series
that was sent almost two months ago still remains here without much
comments and updates from the developer community. I even made the
interface to the logic that decides where to split chunks easily
replaceable, and I deliberately made the logic in the original patch
extremely stupid to entice others, especially the "bup" fanboys, to
come up with a better logic, thinking that giving people an easy
target to shoot for, they may be encouraged to help out. The plan is
not working :-(.

* jc/split-blob:
  chunked-object: streaming checkout
  chunked-object: fallback checkout codepaths
  bulk-checkin: support chunked-object encoding
  bulk-checkin: allow the same data to be multiply hashed
  new representation types in the packstream
  packfile: use varint functions

Conflicts:
	t/t1050-large.sh
Merge branch 'jc/run-hook-env-1' into pu

Not urgent.

Updates run_hook() API to be much less specific to "commit".  It would
only be useful if people start doing more interesting things with hooks.

* jc/run-hook-env-1:
  run_hook(): enhance the interface to pass arbitrary environment
Merge branch 'jc/maint-push-refs-all' into pu

Allows pushing and fetching refs/stash.
Not ready.
There still seem to be other bugs hiding (e.g. try pushing twice).

* jc/maint-push-refs-all:
  get_fetch_map(): tighten checks on dest refs
  fetch/push: allow refs/*:refs/*
Merge branch 'sg/bash-prompt' into pu

This is only the "correction" bits taken from the beginning of a larger
series that is to be rerolled.

By SZEDER Gábor
* sg/bash-prompt:
  completion: respect $GIT_DIR
  completion: use __gitdir() in _git_log()
  tests: add tests for the bash prompt functions in the completion script
  tests: move code to run tests under bash into a helper library
Merge branch 'jc/apply-3way' into pu

"git apply" learns to wiggle the base version and perform three-way merge
when a patch does not exactly apply to the version you have.

* jc/apply-3way:
  apply: document --3way option
  apply: allow rerere() upon --3way results
  apply: register conflicted stages to the index
  apply: plug the three-way merge logic in
  apply: fall back on three-way merge
  apply: accept -3/--3way command line option
  apply: split load_preimage() helper function out
  apply: refactor read_file_or_gitlink()
  apply: clear_image() clears things a bit more

Conflicts:
	builtin/apply.c
Merge branch 'rs/dir-strbuf-read-recursive-fix' into pu

By René Scharfe
* rs/dir-strbuf-read-recursive-fix:
  dir: simplify fill_directory()
  dir: respect string length argument of read_directory_recursive()