[DO NOT MERGE] Peff's review

Why is this enum stored inside the ref? It doesn't actually know whether
it is a HEAD or not, and we never actually store that value there. We
always just store a boolean (remote.c, ll. 1294-1298) and access it as
one (remote.c, l. 1300; transport.c, l. 1259).

The only time we use the enum values is via the "int nonfastforward"
passed to transport_push.  I think it would be a lot clearer to leave
nonfastforward as a single bit in the ref, and then define the enum
elsewhere (or even just use #define if we are not going to use the enum
type). Like this on top of your patch:

I don't think your patch is buggy, because the enum is perfectly capable
of being used as a single bit. But it's confusing to read, because
ref->nonfastforward will never actually be set to the NON_FF_OTHER enum
value.
combine-diff: fix loop index underflow

If both la and context are zero at the start of the loop, la wraps around
and we end up reading from memory far away.  Skip the loop in that case
instead.

Reported-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merge branch 'nd/stream-more' into jch

Use API to read blob data in smaller chunks in more places to
reduce the memory footprint.  In general, looked fairly good.

Will defer til 1.7.10.

* nd/stream-more:
  update-server-info: respect core.bigfilethreshold
  fsck: use streaming API for writing lost-found blobs
  show: use streaming API for showing blobs
  parse_object: avoid putting whole blob in core
  cat-file: use streaming API to print blobs
  Add more large blob test cases
  streaming: make streaming-write-entry to be more reusable
Merge branch 'rs/unpack-trees-leakfix' into jch

Will defer til 1.7.10.

* rs/unpack-trees-leakfix:
  unpack-trees: plug minor memory leak
Merge branch 'jc/commit-hook-authorship' into jch

"git commit --author=$name" did not tell the name that was being
recorded in the resulting commit to hooks, even though it does do so
when the end user overrode the authorship via the "GIT_AUTHOR_NAME"
environment variable.  This is a simpler of the two approaches.

Will defer til 1.7.10.

* jc/commit-hook-authorship:
  commit: pass author/committer info to hooks
  t7503: does pre-commit-hook learn authorship?
  ident.c: add split_ident_line() to parse formatted ident line
Merge branch 'jc/diff-algo-cleanup' into jch

Resurrects the preparatory clean-up patches from another topic that was
discarded, as this would give a saner foundation to build on diff.algo
configuration option series.

Not urgent.

* jc/diff-algo-cleanup:
  xdiff: PATIENCE/HISTOGRAM are not independent option bits
  xdiff: remove XDL_PATCH_* macros
Merge branch 'da/difftool-test' into jch

Makes sure "difftool" options can be given in any order.

* da/difftool-test:
  t7800: Test difftool passing arguments to diff
Merge branch 'jn/diffstat-tests' into jch

Some tests checked the "diff --stat" output when they do not have to,
which unnecessarily made things harder to verify under GETTEXT_POISON.

Not urgent.

* jn/diffstat-tests:
  diffstat summary line varies by locale: miscellany
  test: use numstat instead of diffstat in binary-diff test
  test: use --numstat instead of --stat in "git stash show" tests
  test: test cherry-pick functionality and output separately
  test: modernize funny-names test style
  test: use numstat instead of diffstat in funny-names test
  test: use test_i18ncmp when checking --stat output
Merge branch 'tr/maint-word-diff-regex-sticky' into jch

The regexp configured with wordregex was incorrectly reused across
files.
Not urgent.

* tr/maint-word-diff-regex-sticky:
  diff: tweak a _copy_ of diff_options with word-diff
  diff: refactor the word-diff setup from builtin_diff_cmd
  t4034: diff.*.wordregex should not be "sticky" in --word-diff
Merge branch 'jh/notes-merge-in-git-dir-worktree' into jch

Running "notes merge --commit" failed to perform correctly when run
from any directory inside $GIT_DIR/.  When "notes merge" stops with
conflicts, $GIT_DIR/NOTES_MERGE_WORKTREE is the place a user edits
to resolve it.

Not urgent.

* jh/notes-merge-in-git-dir-worktree:
  notes-merge: Don't remove .git/NOTES_MERGE_WORKTREE; it may be the user's cwd
  notes-merge: use opendir/readdir instead of using read_directory()
  t3310: illustrate failure to "notes merge --commit" inside $GIT_DIR/
  remove_dir_recursively(): Add flag for skipping removal of toplevel dir
Merge branch 'jc/maint-clean-nested-worktree-in-subdir' into jch

"git clean -d -f" (not "-d -f -f") is supposed to protect nested working
trees of independent git repositories that exist in the current project
working tree from getting removed, but the protection applied only to such
working trees that are at the top-level of the current project by mistake.

Not urgent.

* jc/maint-clean-nested-worktree-in-subdir:
  clean: preserve nested git worktree in subdirectories
Merge branch 'zj/test-cred-helper-nicer-prove' into jch

Minor improvement to t0303.
Not urgent.

* zj/test-cred-helper-nicer-prove:
  t0303: resurrect commit message as test documentation
  t0303: immediately bail out w/o GIT_TEST_CREDENTIAL_HELPER
Merge branch 'nl/rebase-i-cheat-sheet' into jch

Not urgent.

* nl/rebase-i-cheat-sheet:
  rebase -i: remind that the lines are top-to-bottom
Merge branch 'nl/http-proxy-more' into jch

The code to talk to http proxies learn to use the same credential
API used to talk to the final http destinations.

Will defer til 1.7.10.

* nl/http-proxy-more:
  http: rename HTTP_REAUTH to HTTP_AUTH_RETRY
  http: Avoid limit of retrying request only twice
  http: handle proxy authentication failure (error 407)
  http: handle proxy proactive authentication
  http: try http_proxy env var when http.proxy config option is not set
Merge branch 'jc/fmt-merge-msg-people' into pu

The "fmt-merge-msg" command learns to list the primary contributors
involved in the side topic you are merging.

Will defer til 1.7.10.

* jc/fmt-merge-msg-people:
  fmt-merge-msg: show those involved in a merged series
Merge branch 'dg/test-from-elsewhere' into pu

Better support for out-of-tree test scripts, but it appears that the
approach needs to be rethought.  By repointing TEST_DIRECTORY to a
directory other than $(pwd)/.., an out of place test script can reach
test helpers and freshly built Git relative to it (GIT_BUILD_DIR is
a mere short-hand for $TEST_DIRECTORY/..).

Discussion stalled.

* dg/test-from-elsewhere:
  Support out-of-tree Valgrind tests
  Allow overriding GIT_BUILD_DIR
Merge branch 'ss/git-svn-prompt-sans-terminal' into pu

The bottom one has been replaced with a rewrite based on comments
from Ævar. The second one needs more work, both in perl/Git.pm and
prompt.c, to give precedence to tty over SSH_ASKPASS when terminal
is available.

* ss/git-svn-prompt-sans-terminal:
  fixup! 15eaaf4
  git-svn, perl/Git.pm: extend Git::prompt helper for querying users
  perl/Git.pm: "prompt" helper to honor GIT_ASKPASS and SSH_ASKPASS
Merge branch 'hv/submodule-recurse-push' into pu

The bottom one was not clearly explained and needs a reroll.

* hv/submodule-recurse-push:
  push: teach --recurse-submodules the on-demand option
  Refactor submodule push check to use string list instead of integer
  Teach revision walking machinery to walk multiple times sequencially

Conflicts:
	transport.h
Merge branch 'nd/columns' into pu

Rerolled again.  Modulo minor nits, looked nicer than the previous round.

* nd/columns:
  column: support grouping entries
  column: support "denser" mode
  ls-files: support --column
  tag: add --column
  column: support piping stdout to external git-column process
  status: add --column
  branch: add --column
  help: reuse print_columns() for help -a
  column: add dense layout support
  column: add columnar layout
  Stop starting pager recursively
  Add column layout skeleton and git-column
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
  varint-in-pack: refactor varint encoding/decoding

Conflicts:
	t/t1050-large.sh