Allow shallow-cloning of submodules with "git submodule update".

* fg/submodule-clone-depth:
  Add --depth to submodule update/add

Add the --depth option to the add and update commands of "git submodule",
which is then passed on to the clone command. This is useful when the
submodule(s) are huge and you're not really interested in anything but
the latest commit.

Tests are added and some indention adjustments were made to conform to the
rest of the testfile on "submodule update can handle symbolic links in pwd".

Signed-off-by: Fredrik Gustafsson <iveqy@iveqy.com>
Acked-by: Jens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Users can set submodule.$name.update to '!command' which will cause
'command' to be run instead of checkout/merge/rebase. This allows
the user finer-grained control over how the update is done.

The primary motivation for this was interoperability with stgit;
however being able to intercept the submodule update process may
prove useful for integrating with or extending other tools.

Signed-off-by: Chris Packham <judge.packham@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Allow various subcommands of "git submodule" to be run not from the
top of the working tree of the superproject.

* jk/submodule-subdirectory-ok:
  submodule: drop the top-level requirement
  rev-parse: add --prefix option
  submodule: show full path in error message
  t7403: add missing && chaining
  t7403: modernize style
  t7401: make indentation consistent

Many "git submodule" operations do not work on a submodule at a
path whose name is not in ASCII.

* fg/submodule-non-ascii-path:
  t7400: test of UTF-8 submodule names pass under Mac OS
  handle multibyte characters in name

Use the new rev-parse --prefix option to process all paths given to the
submodule command, dropping the requirement that it be run from the
top-level of the repository.

Since the interpretation of a relative submodule URL depends on whether
or not "remote.origin.url" is configured, explicitly block relative URLs
in "git submodule add" when not at the top level of the working tree.

Signed-off-by: John Keeping <john@keeping.me.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

When --recursive was added to "submodule foreach" in commit 15fc56a (git
submodule foreach: Add --recursive to recurse into nested submodules,
2009-08-19), the error message when the script returns a non-zero status
was not updated to contain $prefix to show the full path.  Fix this.

Signed-off-by: John Keeping <john@keeping.me.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

set_rev_name is a possiblly expensive operation. If a submodule has
changes in it, set_rev_name was called twice.

Move call to set_rev_name so it's only called once, no matter which
codepath is taken.

Signed-off-by: Fredrik Gustafsson <iveqy@iveqy.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Many "git submodule" operations do not work on a submodule at a path whose
name is not in ASCII.

This is because "git ls-files" is used to find which paths are bound to
submodules to the current working tree, and the output is C-quoted by default
for non ASCII pathnames.

Tell "git ls-files" to not C-quote its output, which is easier than unwrapping
C-quote ourselves.

Signed-off-by: Fredrik Gustafsson <iveqy@iveqy.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

A finishing touch to the new topic in 1.8.3.

* jl/submodule-deinit:
  submodule deinit: clarify work tree removal message