To correctly perform its testing function,
test-dump-untracked-cache should not change the state of the
untracked cache in the index.

As a previous patch makes read_index_from() change the state of
the untracked cache and as test-dump-untracked-cache indirectly
calls this function, we need a mechanism to prevent
read_index_from() from changing the untracked cache state when
it's called from test-dump-untracked-cache.
Signed-off-by: NChristian Couder <chriscool@tuxfamily.org>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

When we know that mtime on directory as given by the environment
is usable for the purpose of untracked cache, we may want the
untracked cache to be always used without any mtime test or
kernel name check being performed.

Also when we know that mtime is not usable for the purpose of
untracked cache, for example because the repo is shared over a
network file system, we may want the untracked-cache to be
automatically removed from the index.

Allow the user to express such preference by setting the
'core.untrackedCache' configuration variable, which can take
'keep', 'false', or 'true' and default to 'keep'.

When read_index_from() is called, it now adds or removes the
untracked cache in the index to respect the value of this
variable. So it does nothing if the value is `keep` or if the
variable is unset; it adds the untracked cache if the value is
`true`; and it removes the cache if the value is `false`.

`git update-index --[no-|force-]untracked-cache` still adds the
untracked cache to, or removes it, from the index, but this
shows a warning if it goes against the value of
core.untrackedCache, because the next time the index is read
the untracked cache will be added or removed if the
configuration is set to do so.

Also `--untracked-cache` used to check that the underlying
operating system and file system change `st_mtime` field of a
directory if files are added or deleted in that directory. But
because those tests take a long time, `--untracked-cache` no
longer performs them. Instead, there is now
`--test-untracked-cache` to perform the tests. This change
makes `--untracked-cache` the same as `--force-untracked-cache`.

This last change is backward incompatible and should be
mentioned in the release notes.
Helped-by: NDuy Nguyen <pclouds@gmail.com>
Helped-by: NTorsten Bögershausen <tboegi@web.de>
Helped-by: NStefan Beller <sbeller@google.com>
Signed-off-by: NChristian Couder <chriscool@tuxfamily.org>
Signed-off-by: NÆvar Arnfjörð Bjarmason <avarab@gmail.com>

read-cache: Duy'sfixup
Signed-off-by: NChristian Couder <chriscool@tuxfamily.org>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

It is not a good idea to compare kernel versions and disable
the untracked cache if it changes, as people may upgrade and
still want the untracked cache to work. So let's just
compare work tree locations and kernel name to decide if we
should disable it.

Also storing many locations in the ident field and comparing
to any of them can be dangerous if GIT_WORK_TREE is used with
different values. So let's just store one location, the
location of the current work tree.

The downside is that untracked cache can only be used by one
type of OS for now. Exporting a git repo to different clients
via a network to e.g. Linux and Windows means that only one
can use the untracked cache.

If the location changed in the ident field and we still want
an untracked cache, let's delete the cache and recreate it.

Note that if an untracked cache has been created by a
previous Git version, then the kernel version is stored in
the ident field. As we now compare with just the kernel
name the comparison will fail and the untracked cache will
be disabled until it's recreated.
Helped-by: NTorsten Bögershausen <tboegi@web.de>
Signed-off-by: NChristian Couder <chriscool@tuxfamily.org>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Factor out code into remove_untracked_cache(), which will be used
in a later commit.
Signed-off-by: NChristian Couder <chriscool@tuxfamily.org>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Factor out code into new_untracked_cache() and
add_untracked_cache(), which will be used
in later commits.
Helped-by: NEric Sunshine <sunshine@sunshineco.com>
Signed-off-by: NChristian Couder <chriscool@tuxfamily.org>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NChristian Couder <chriscool@tuxfamily.org>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Attempting to flip the untracked-cache feature on for a random index
file with

    cd /random/unrelated/place
    git --git-dir=/somewhere/else/.git update-index --untracked-cache

would not work as you might expect. Because flipping the feature on
in the index also records the location of the corresponding working
tree (/random/unrelated/place in the above example), when the index
is subsequently used to keep track of files in the working tree in
/somewhere/else, the feature is disabled.

With this patch "git update-index --[test-]untracked-cache" tells the
user in which directory tests are performed. This makes it easy to
spot any problem.

Also in verbose mode, let's tell the user when the cache is enabled
or disabled.
Helped-by: NDuy Nguyen <pclouds@gmail.com>
Signed-off-by: NChristian Couder <chriscool@tuxfamily.org>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

It is nice to just be able to test if untracked cache is
supported without enabling it.
Helped-by: NDavid Turner <dturner@twopensource.com>
Signed-off-by: NChristian Couder <chriscool@tuxfamily.org>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Helped-by: NDuy Nguyen <pclouds@gmail.com>
Signed-off-by: NChristian Couder <chriscool@tuxfamily.org>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NChristian Couder <chriscool@tuxfamily.org>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The exit code of git-fsck didnot reflect some types of errors found
in packed objects, which has been corrected.

* dt/fsck-verify-pack-error:
  verify_pack: do not ignore return value of verification function

A fix-up for recent topic.

* ep/ident-with-getaddrinfo:
  ident: fix undefined variable when NO_IPV6 is set
  ident.c: add support for IPv6

"git p4" used to import Perforce CLs that touch only paths outside
the client spec as empty commits.  It has been corrected to ignore
them instead, with a new configuration git-p4.keepEmptyCommits as a
backward compatibility knob.

* ls/p4-keep-empty-commits:
  git-p4: add option to keep empty commits

A fix-up for recent topic.

* jk/send-email-complete-aliases:
  completion: fix completing unstuck email alias arguments

A fix-up for recent topic.

* ep/ident-with-getaddrinfo:
  ident: fix undefined variable when NO_IPV6 is set

The helper used to iterate over loose object directories to prune
stale objects did not closedir() immediately when it is done with a
directory--a callback such as the one used for "git prune" may want
to do rmdir(), but it would fail on open directory on platforms
such as WinXP.

* jk/prune-mtime:
  prune: close directory earlier during loose-object directory traversal

"git p4" used to import Perforce CLs that touch only paths outside
the client spec as empty commits.  It has been corrected to ignore
them instead, with a new configuration git-p4.keepEmptyCommits as a
backward compatibility knob.

* ls/p4-keep-empty-commits:
  git-p4: add option to keep empty commits

The helper used to iterate over loose object directories to prune
stale objects did not closedir() immediately when it is done with a
directory--a callback such as the one used for "git prune" may want
to do rmdir(), but it would fail on open directory on platforms
such as WinXP.

* jk/prune-mtime:
  prune: close directory earlier during loose-object directory traversal

Completing unstuck form of email aliases doesn't quite work:

  $ git send-email --to <TAB>
  alice   bob     cecil
  $ git send-email --to a<TAB>
  alice   bob     cecil

While listing email aliases works as expected, the second case should
just complete to 'alice', but it keeps offering all email aliases
instead.

The cause for this behavior is that in this case we mistakenly tell
__gitcomp() explicitly that the current word to be completed is empty,
while in reality it is not.  As a result __gitcomp() doesn't filter
out non-matching aliases, so all aliases end up being offered over and
over again.

Fix this by not passing the current word to be completed to
__gitcomp() and letting it go the default route and grab it from the
'$cur' variable.  Don't pass empty prefix either, because it's assumed
to be empty when unspecified, so it's not necessary.
Signed-off-by: NSZEDER Gábor <szeder@ira.uka.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Commit 00bce77f (ident.c: add support for IPv6, 2015-11-27)
moved the "gethostbyname" call out of "add_domainname" and
into the helper function "canonical_name". But when moving
the code, it forgot that the "buf" variable is passed as
"host" in the helper.
Reported-by: Njohan defries <johandefries@gmail.com>
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NJunio C Hamano <gitster@pobox.com>

* maint:
  Prepare for 2.6.5

This back-merges hopefully the last batch of trivially correct fixes
to the 2.6.x maintenance track from the master branch.
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

mark_tree_uninteresting() has code to handle the case where it gets
passed a NULL pointer in its 'tree' parameter, but the function had
'object = &tree->object' assignment before checking if tree is
NULL.  This gives a compiler an excuse to declare that tree will
never be NULL and apply a wrong optimization.  Avoid it.

* sn/null-pointer-arith-in-mark-tree-uninteresting:
  revision.c: fix possible null pointer arithmetic

Cosmetic improvement to lock-file error messages.

* sg/lock-file-commit-error:
  Make error message after failing commit_lock_file() less confusing

* cb/t3404-shellquote:
  t3404: fix quoting of redirect for some versions of bash

* sb/doc-submodule-sync-recursive:
  document submodule sync --recursive

* nd/doc-check-ref-format-typo:
  git-check-ref-format.txt: typo, s/avoids/avoid/

Code simplification.

* rs/show-branch-argv-array:
  show-branch: use argv_array for default arguments

Code simplification.

* rs/pop-commit:
  use pop_commit() for consuming the first entry of a struct commit_list

Update "git subtree" (in contrib/) so that it can take whitespaces
in the pathnames, not only in the in-tree pathname but the name of
the directory that the repository is in.

* as/subtree-with-spaces:
  contrib/subtree: respect spaces in a repository path
  t7900-subtree: test the "space in a subdirectory name" case

Because "test_when_finished" in our test framework queues the
clean-up tasks to be done in a shell variable, it should not be
used inside a subshell.  Add a mechanism to allow 'bash' to catch
such uses, and fix the ones that were found.

* jk/test-lint-forbid-when-finished-in-subshell:
  test-lib-functions: detect test_when_finished in subshell
  t7800: don't use test_config in a subshell
  test-lib-functions: support "test_config -C <dir> ..."
  t5801: don't use test_when_finished in a subshell
  t7610: don't use test_config in a subshell

mark_tree_uninteresting() has code to handle the case where it gets
passed a NULL pointer in its 'tree' parameter, but the function had
'object = &tree->object' assignment before checking if tree is
NULL.  This gives a compiler an excuse to declare that tree will
never be NULL and apply a wrong optimization.  Avoid it.

* sn/null-pointer-arith-in-mark-tree-uninteresting:
  revision.c: fix possible null pointer arithmetic

* sb/doc-submodule-sync-recursive:
  document submodule sync --recursive

* cb/t3404-shellquote:
  t3404: fix quoting of redirect for some versions of bash

Cosmetic improvement to lock-file error messages.

* sg/lock-file-commit-error:
  Make error message after failing commit_lock_file() less confusing

Signed-off-by: NJunio C Hamano <gitster@pobox.com>