xread, xwrite: limit size of IO to 8MB

Checking out 2GB or more through an external filter (see test) fails
on Mac OS X 10.8.4 (12E55) for a 64-bit executable with:

    error: read from external filter cat failed
    error: cannot feed the input to external filter cat
    error: cat died of signal 13
    error: external filter cat failed 141
    error: external filter cat failed

The reason is that read() immediately returns with EINVAL when asked
to read more than 2GB.  According to POSIX [1], if the value of
nbyte passed to read() is greater than SSIZE_MAX, the result is
implementation-defined.  The write function has the same restriction
[2].  Since OS X still supports running 32-bit executables, the
32-bit limit (SSIZE_MAX = INT_MAX = 2GB - 1) seems to be also
imposed on 64-bit executables under certain conditions.  For write,
the problem has been addressed earlier [6c642a].

Address the problem for read() and write() differently, by limiting
size of IO chunks unconditionally on all platforms in xread() and
xwrite().  Large chunks only cause problems, like causing latencies
when killing the process, even if OS X was not buggy.  Doing IO in
reasonably sized smaller chunks should have no negative impact on
performance.

The compat wrapper clipped_write() introduced earlier [6c642a] is
not needed anymore.  It will be reverted in a separate commit.  The
new test catches read and write problems.

Note that 'git add' exits with 0 even if it prints filtering errors
to stderr.  The test, therefore, checks stderr.  'git add' should
probably be changed (sometime in another commit) to exit with
nonzero if filtering fails.  The test could then be changed to use
test_must_fail.

Thanks to the following people for suggestions and testing:

    Johannes Sixt <j6t@kdbg.org>
    John Keeping <john@keeping.me.uk>
    Jonathan Nieder <jrnieder@gmail.com>
    Kyle J. McKay <mackyle@gmail.com>
    Linus Torvalds <torvalds@linux-foundation.org>
    Torsten Bögershausen <tboegi@web.de>

[1] http://pubs.opengroup.org/onlinepubs/009695399/functions/read.html
[2] http://pubs.opengroup.org/onlinepubs/009695399/functions/write.html

[6c642a] commit 6c642a878688adf46b226903858b53e2d31ac5c3
    compate/clipped-write.c: large write(2) fails on Mac OS X/XNU

Signed-off-by: Steffen Prohaska <prohaska@zib.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Revert "compat/clipped-write.c: large write(2) fails on Mac OS X/XNU"

This reverts commit 6c642a878688adf46b226903858b53e2d31ac5c3.

The previous commit introduced a size limit on IO chunks on all
platforms.  The compat clipped_write() is not needed anymore.

Signed-off-by: Steffen Prohaska <prohaska@zib.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
submodule: fix confusing variable name

cmd_summary reads the output of git diff, but reads in the submodule path into a
variable called name.  Since this variable does not contain the name of the
submodule, but the path, rename it to be clearer what data it actually holds.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Acked-by: Jens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
submodule: don't print status output with ignore=all

git status prints information for submodules, but it should ignore the status of
those which have submodule.<name>.ignore set to all.  Fix it so that it does
properly ignore those which have that setting either in .git/config or in
.gitmodules.

Not ignored are submodules that are added, deleted, or moved (which is
essentially a combination of the first two) because it is not easily possible to
determine the old path once a move has occurred, nor is it easily possible to
detect which adds and deletions are moves and which are not.  This also
preserves the previous behavior of always listing modules which are to be
deleted.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Acked-by: Jens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
read-cache: use fixed width integer types

Use the fixed width integer types uint16_t and uint32_t for on-disk
structures; unsigned short and unsigned int do not have a guaranteed
size.

Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
gitweb: ensure OPML text fits inside its box

The rss_logo CSS style has a fixed width which is too narrow for
the string "OPML". Replace the fixed width with horizontal padding
so the text fits with nice margins.

Signed-off-by: Tony Finch <dot@dotat.at>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
gitweb: vertically centre contents of page footer

Signed-off-by: Tony Finch <dot@dotat.at>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
gitweb: omit the repository owner when it is unset

On the repository summary page, leave the owner line out if the
repo does not have an owner, rather than displaying a labelled empty
field. This does not affect the owner column in the projects list
page, which is present unless $omit_owner is true.

Signed-off-by: Tony Finch <dot@dotat.at>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
gitweb: make search help link less ugly

The search help link was a superscript question mark right next to
a drop-down menu, which looks misaligned and is a cramped and
awkward click target. Remove the superscript tags and add some
spacing to fix these nits. Add a title attribute to provide an
explanatory mouseover.

Signed-off-by: Tony Finch <dot@dotat.at>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
config: properly range-check integer values

When we look at a config value as an integer using the
git_config_int function, we carefully range-check the value
we get and complain if it is out of our range. But the range
we compare to is that of a "long", which we then cast to an
"int" in the function's return value. This means that on
systems where "int" and "long" have different sizes (e.g.,
LP64 systems), we may pass the range check, but then return
nonsense by truncating the value as we cast it to an int.

We can solve this by converting git_parse_long into
git_parse_int, and range-checking the "int" range. Nobody
actually cared that we used a "long" internally, since the
result was truncated anyway, and there were no other callers
of git_parse_long.

Of the existing callers, all of them expect small-ish values
that are fine for an "int", and should not be impacted
except when nonsense is fed to them. The one arguable
exception is http.lowSpeedLimit, which is given in bytes per
second, and is fed to curl as a long. However, nobody is
likely to consider 2GB/sec as "low speed", and even if they
did, the new behavior is much better (it barfs and complains
rather than considering the value negative and silently
ignoring it).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
teach git-config to output large integers

Internally we use "unsigned long" to represent large config
values like packed window memory sizes, packfile size
limits, etc.  On 32-bit systems, this limits these config
options to 4G (and we detect and complain about overflow).
On 64-bit systems, they get the full 64-bit range.

However, there is no way for script callers of git-config to
see the numeric values (they cannot treat them as pure
strings, since they would want git-config to process "3g"
into "3221225472").

This patch teaches git-config a "--ulong" type that can
output these unsigned long values, allowing scripts to
examine the values as the internal code would.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Document the HTTP transport protocols

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Revised-by: Tay Ray Chuan <rctay89@gmail.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
rebase --preserve-merges: ignore "merge.log" config

When "merge.log" config is set, "rebase --preserve-merges" will add
the log lines to the message of the rebased merge commit.  A rebase
should not modify a commit message automatically.

Teach "git-rebase" to ignore that configuration by passing
"--no-log" to the git-merge call.

Signed-off-by: Ralf Thielow <ralf.thielow@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
t3404: preserve test_tick state across short SHA-1 collision test

The short SHA-1 collision test requires carefully crafted commits in
order to ensure a collision at rebase time. This involves managing state
which impacts the resulting SHA-1, including commit time. To accomplish
this, test_tick is set to a known state for the short SHA-1 collision
test.

Unfortunately, doing so throws away the existing state of test_tick,
which may be problematic for subsequently added tests. Fix this by
preserving the existing state of test_tick across the short SHA-1
collision test.

Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
t3404: make tests more self-contained

As its very first action, t3404 installs (via set_fake_editor) a
specialized $EDITOR which simplifies automated 'rebase -i' testing. Many
tests rely upon this setting, thus tests which need a different editor
must take extra care upon completion to restore $EDITOR in order to
avoid breaking following tests. This places extra burden upon such tests
and requires that they undesirably have extra knowledge about
surrounding tests. Ease this burden by having each test install the
$EDITOR it requires, rather than relying upon a global setting.

Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
t3404: simplify short SHA-1 collision test

The short SHA-1 collision test employs two "magic" values in commit
messages to trigger an "ambiguous SHA-1 error" during 'rebase -i' -- one
for 'collide3' during setup, and one for 'collide2' at rebase time --
even though the collision can just as easily be triggered by a single
magic value at rebase time only. The setup-time 'collide3' magic value
serves no purpose [1], but can easily mislead readers into thinking that
it is somehow significant even though it is not. Drop this unneeded bit
of magic.

As a side-effect, this also simplifies the setup-time "test_commit
collide3" invocation, making it easier to read.

[1]: The magic value on 'collide3' gave it a short SHA-1 prefix of
"badbeef" which could be spotted easily in verbose output during
development of the test, but is otherwise not meaningful or helpful.

Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
git-completion.bash: use correct Bash/Zsh array length syntax

The syntax for retrieving the number of elements in an array is:

   ${#name[@]}

Signed-off-by: Brandon Casey <drafnel@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
t9902-completion.sh: old Bash still does not support array+=('') notation

Old Bash (3.0) which is distributed with RHEL 4.X and other ancient
platforms that are still in wide use, does not understand the
array+=() notation.  Let's use an explicit assignment to the new array
element which works everywhere, like:

   array[${#array[@]}+1]=''

The right-hand side '' is not strictly necessary, but in this case
I think it is more clear.

Signed-off-by: Brandon Casey <drafnel@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
contrib/git-prompt.sh: handle missing 'printf -v' more gracefully

Old Bash (3.0) which is distributed with RHEL 4.X and other ancient
platforms that are still in wide use, do not have a printf that
supports -v.  Neither does Zsh (which is already handled in the code).

As suggested by Junio, let's test whether printf supports the -v
option and store the result.  Then later, we can use it to
determine whether 'printf -v' can be used, or whether printf
must be called in a subshell.

Signed-off-by: Brandon Casey <drafnel@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merge branch 'es/rebase-i-no-abbrev' into next

* es/rebase-i-no-abbrev:
  t3404: simplify short SHA-1 collision test
  t3404: make tests more self-contained
  t3404: preserve test_tick state across short SHA-1 collision test