setup_reflog_action: document the rules for using GIT_REFLOG_ACTION

The set_reflog_action helper (in git-sh-setup) is designed to be
used once at the very top of a program, like this in "git am", for
example:

	set_reflog_action am

The helper function sets the given string to GIT_REFLOG_ACTION only
when GIT_REFLOG_ACTION is not yet set.  Thanks to this, "git am",
when run as the top-level program, will use "am" in GIT_REFLOG_ACTION
and the reflog entries made by whatever it does will record the
updates of refs done by "am".

Because of the conditional assignment, when "git am" is run as a
subprogram (i.e. an implementation detail) of "git rebase" that
already sets GIT_REFLOG_ACTION to its own name, the call in "git am"
to the helper function at the beginning will *not* have any effect.

So "git rebase" can do this:

	set_reflog_action rebase
	... do its own preparation, like checking out "onto" commit
        ... decide to do "format-patch" to "am" pipeline
        	git format-patch --stdout >mbox
		git am mbox

and the reflog entries made inside "git am" invocation will say
"rebase", not "am".

Calls to "git" commands that update refs would use GIT_REFLOG_ACTION
to record who did that update.  Most such calls in scripted Porcelains
do not define custom reflog message and rely on GIT_REFLOG_ACTION to
contain its (or its caller's, when it is called as a subprogram) name.

If a scripted Porcelain wants to record a custom reflog message for
a single invocation of "git" command (e.g. when "git rebase" uses
"git checkout" to detach HEAD at the commit a series is to be
replayed on), it needs to set GIT_REFLOG_ACTION to the custom
message and export it while calling the "git" command, but such an
assignment must be restricted to that single "git" invocation and
should not be left behind to affect later codepath.

Document the rules to avoid future confusion.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
repack: rewrite the shell script in C

The motivation of this patch is to get closer to a goal of being
able to have a core subset of git functionality built in to git.
That would mean

 * people on Windows could get a copy of at least the core parts
   of Git without having to install a Unix-style shell

 * people using git in on servers with chrooted environments
   do not need to worry about standard tools lacking for shell
   scripts.

This patch is meant to be mostly a literal translation of the
git-repack script; the intent is that later patches would start using
more library facilities, but this patch is meant to be as close to a
no-op as possible so it doesn't do that kind of thing.

Signed-off-by: Stefan Beller <stefanbeller@googlemail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
repack: retain the return value of pack-objects

During the review process of the previous commit (repack: rewrite the
shell script in C), Johannes Sixt proposed to retain any exit codes from
the sub-process, which makes it probably more obvious in case of failure.

As the commit before should behave as close to the original shell
script, the proposed change is put in this extra commit.
The infrastructure however was already setup in the previous commit.
(Having a local 'ret' variable)

Signed-off-by: Stefan Beller <stefanbeller@googlemail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
repack: improve warnings about failure of renaming and removing files

Signed-off-by: Stefan Beller <stefanbeller@googlemail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
clone: send diagnostic messages to stderr

Putting messages like "Cloning into.." and "done" on stdout
is un-Unix and uselessly clutters the stdout channel. Send
them to stderr.

We have to tweak two tests to accommodate this:

  1. t5601 checks for doubled output due to forking, and
     doesn't actually care where the output goes; adjust it
     to check stderr.

  2. t5702 is trying to test whether progress output was
     sent to stderr, but naively does so by checking
     whether stderr produced any output. Instead, have it
     look for "%", a token found in progress output but not
     elsewhere (and which lets us avoid hard-coding the
     progress text in the test).

This should not regress any scripts that try to parse the
current output, as the output is already internationalized
and therefore unstable.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
clone: treat "checking connectivity" like other progress

When stderr does not point to a tty, we typically suppress
"we are now in this phase" progress reporting (e.g., we ask
the server not to send us "counting objects" and the like).

The new "checking connectivity" message is in the same vein,
and should be suppressed. Since clone relies on the
transport code to make the decision, we can simply sneak a
peek at the "progress" field of the transport struct. That
properly takes into account both the verbosity and progress
options we were given, as well as the result of isatty().

Note that we do not set up that progress flag for a local
clone, as we do not fetch using the transport at all. That's
acceptable here, though, because we also do not perform a
connectivity check in that case.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
clone: always set transport options

A clone will always create a transport struct, whether we
are cloning locally or using an actual protocol. In the
local case, we only use the transport to get the list of
refs, and then transfer the objects out-of-band.

However, there are many options that we do not bother
setting up in the local case. For the most part, these are
noops, because they only affect the object-fetching stage
(e.g., the --depth option).  However, some options do have a
visible impact. For example, giving the path to upload-pack
via "-u" does not currently work for a local clone, even
though we need upload-pack to get the ref list.

We can just drop the conditional entirely and set these
options for both local and non-local clones. Rather than
keep track of which options impact the object versus the ref
fetching stage, we can simply let the noops be noops (and
the cost of setting the options in the first place is not
high).

The one exception is that we also check that the transport
provides both a "get_refs_list" and a "fetch" method. We
will now be checking the former for both cases (which is
good, since a transport that cannot fetch refs would not
work for a local clone), and we tweak the conditional to
check for a "fetch" only when we are non-local.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merge branch 'master' into next

* master:
  doc: don't claim that cherry calls patch-id
  git-remote-mediawiki: bugfix for pages w/ >500 revisions
  sample pre-commit hook: use --bool when retrieving config var
  clone: add a period after "done" to end the sentence
Merge branch 'jk/clone-progress-to-stderr' into next

Some progress and diagnostic messages from "git clone" were
incorrectly sent to the standard output stream, not to the standard
error stream.

* jk/clone-progress-to-stderr:
  clone: always set transport options
  clone: treat "checking connectivity" like other progress
  clone: send diagnostic messages to stderr

# Conflicts:
# 	builtin/clone.c
Merge branch 'sb/repack-in-c' into next

Rerolled, and I think it is in a reasonably good shape.

* sb/repack-in-c:
  repack: improve warnings about failure of renaming and removing files
  repack: retain the return value of pack-objects
  repack: rewrite the shell script in C
Merge branch 'jc/reflog-doc' into next

Document rules to use GIT_REFLOG_ACTION variable in the scripted
Porcelain.  git-rebase--interactive locally violates them, but it
is a leaf user that does not call out to or dot-source other
scripts, so it does not urgently need to be fixed.

* jc/reflog-doc:
  setup_reflog_action: document the rules for using GIT_REFLOG_ACTION

# Conflicts:
# 	Documentation/git.txt
Merge branch 'master' into next

* master:
  contrib: remove ciabot
  Git 1.8.4.1
Merge branch 'jk/archive-reachability' into HEAD

* jk/archive-reachability:
  archive: ignore blob objects when checking reachability
  list-objects: optimize "revs->blob_objects = 0" case
  upload-archive: restrict remote objects with reachability check
Merge branch 'jk/blame-tree' into HEAD

* jk/blame-tree:
  add blame-tree command
  combine-diff: zero memory used for callback filepairs
  teach tree-diff a max-depth parameter
  within_depth: fix return for empty path
Merge branch 'jk/bogus-ident-segfault' into HEAD

* jk/bogus-ident-segfault:
  fsck: check "tagger" lines
  skip_prefix: return a non-const pointer
Merge branch 'jk/builtin-attr' into HEAD

* jk/builtin-attr:
  attr: map builtin userdiff drivers to well-known extensions
Merge branch 'jk/child-cleanup' into HEAD

* jk/child-cleanup:
  send-pack: kill pack-objects helper on signal or exit
Merge branch 'jk/clone-stderr' into HEAD

* jk/clone-stderr:
  clone: always set transport options
  clone: treat "checking connectivity" like other progress
  clone: send diagnostic messages to stderr
Merge branch 'jk/config-sources' into HEAD

* jk/config-sources:
  show sources of config options (WIP)
Merge branch 'jk/describe' into HEAD

* jk/describe:
  describe WIP