xdiff: remove XDL_PATCH_* macros

These are not used anywhere in our codebase, and the bit assignment
definition is merely confusing.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
xdiff: PATIENCE/HISTOGRAM are not independent option bits

Because the default Myers, patience and histogram algorithms cannot be in
effect at the same time, XDL_PATIENCE_DIFF and XDL_HISTOGRAM_DIFF are not
independent bits.  Instead of wasting one bit per algorithm, define a few
macros to access the few bits they occupy and update the code that access
them.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
push: Provide situational hints for non-fast-forward errors

Pushing a non-fast-forward update to a remote repository will result in
an error, but the hint text doesn't provide the correct resolution in
every case. Give better resolution advice in three push scenarios:

1) If you push your current branch and it triggers a non-fast-forward
error, you should merge remote changes with 'git pull' before pushing
again.

2) If you push to a shared repository others push to, and your local
tracking branches are not kept up to date, the 'matching refs' default
will generate non-fast-forward errors on outdated branches. If this is
your workflow, the 'matching refs' default is not for you. Consider
setting the 'push.default' configuration variable to 'current' or
'upstream' to ensure only your current branch is pushed.

3) If you explicitly specify a ref that is not your current branch or
push matching branches with ':', you will generate a non-fast-forward
error if any pushed branch tip is out of date. You should checkout the
offending branch and merge remote changes before pushing again.

Teach transport.c to recognize these scenarios and configure push.c
to hint for them. If 'git push's default behavior changes or we
discover more scenarios, extension is easy. Standardize on the
advice API and add three new advice variables, 'pushNonFFCurrent',
'pushNonFFDefault', and 'pushNonFFMatching'. Setting any of these
to 'false' will disable their affiliated advice. Setting
'pushNonFastForward' to false will disable all three, thus preserving the
config option for users who already set it, but guaranteeing new
users won't disable push advice accidentally.

Based-on-patch-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Christopher Tiwald <christiwald@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
rebase -i: remind that the lines are top-to-bottom

Nelson Benitez Leon opened a discussion with a patch with this in the
note:

    Hi, I was using git rebase -i for some time now and never occured to
    me I could reorder the commit lines to affect the order the commits
    are applied, learnt that recently from a git tutorial.

Nelson's patch was to stress the fact that the lines in the insn sheet can
be re-ordered in a much more verbose way.  Let's add a one-liner reminder
and also remind that the lines in the insn sheet is read from top to
bottom, unlike the "git log" output.

Discussion-triggered-by: Nelson Benitez Leon
Signed-off-by: Junio C Hamano <gitster@pobox.com>
clean up struct ref's nonfastforward field

Each ref structure contains a "nonfastforward" field which
is set during push to show whether the ref rewound history.
Originally this was a single bit, but it was changed in
f25950f (push: Provide situational hints for non-fast-forward
errors) to an enum differentiating a non-ff of the current
branch versus another branch.

However, we never actually set the member according to the
enum values, nor did we ever read it expecting anything but
a boolean value. But we did use the side effect of declaring
the enum constants to store those values in a totally
different integer variable. The code as-is isn't buggy, but
the enum declaration inside "struct ref" is somewhat
misleading.

Let's convert nonfastforward back into a single bit, and
then define the NON_FF_* constants closer to where they
would be used (they are returned via the "int *nonfastforward"
parameter to transport_push, so we can define them there).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
http-backend: respect existing GIT_COMMITTER_* variables

The http-backend program sets default GIT_COMMITTER_NAME and
GIT_COMMITTER_EMAIL variables based on the REMOTE_USER and
REMOTE_ADDR variables provided by the webserver. However, it
unconditionally overwrites any existing GIT_COMMITTER
variables, which may have been customized by site-specific
code in the webserver (or in a script wrapping http-backend).

Let's leave those variables intact if they already exist,
assuming that any such configuration was intentional. There
is a slight chance of a regression if somebody has set
GIT_COMMITTER_* for the entire webserver, not intending it
to leak through http-backend. We could protect against this
by passing the information in alternate variables.  However,
it seems unlikely that anyone will care about that
regression, and there is value in the simplicity of using
the common variable names that are used elsewhere in git.

While we're tweaking the environment-handling in
http-backend, let's switch it to use argv_array to handle
the list of variables. That makes the memory management much
simpler.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Avoid bug in Solaris xpg4/sed as used in submodule

The sed provided by Solaris in /usr/xpg4/bin has a bug whereby an
unanchored regex using * for zero or more repetitions sees two
separate matches fed to the substitution engine in some cases.

This is evidenced by:

$ for sed in /usr/xpg4/bin/sed /usr/bin/sed /opt/csw/gnu/sed; do \
echo 'ab' | $sed -e 's|[a]*|X|g'; \
done
XXbX
XbX
XbX

This bug was triggered during a git submodule clone operation as
exercised in the setup stage of t5526-fetch-submodules when using the
default SANE_TOOL_PATH for Solaris.  It led to paths such as
..../.. being used in the submodule .git gitdir reference.

Using the expression 's|\([^/]*\(/*\)\)|..\2|g' provides the desired
result with all three three tested sed implementations but is harder
to read.  As we do not need to handle fully qualified paths though,
the expression could actually be [^/]+ which isn't properly handled
either.  Instead, use [^/][^/]*, as suggested by Andreas Schwab, which
works on all three tested sed implementations.

The new expression is semantically different than the original one.
It will not place a leading '..' on a fully qualified path as the
original expression did.  All of the paths being passed through this
regex are relative and did not rely on this behaviour so it's a safe
change.

Signed-off-by: Ben Walton <bwalton@artsci.utoronto.ca>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
rev-parse --show-prefix: add in trailing newline

Print out a trailing newline when --show-prefix is run with cwd
at the top level of the tree which results in an empty prefix.
Behavior is now like --show-cdup.

Fixes an expected failure in t1501.

Signed-off-by: Ross Lagerwall <rosslagerwall@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
unpack-trees: don't perform any index operation if we're not merging

src[0] points to the index entry in the merge case and to the first
tree to unpack in the non-merge case.  We only want to mark the index
entry, so check first if we're merging.

Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
unpack-trees: plug minor memory leak

The allocations made by unpack_nondirectories() using create_ce_entry()
are never freed.

In the non-merge case, we duplicate them using add_entry() and later
only look at the first allocated element (src[0]), perhaps even only
by mistake.  Split out the actual addition from add_entry() into the
new helper do_add_entry() and call this non-duplicating function
instead of add_entry() to avoid the leak.

Valgrind reports this for the command "git archive v1.7.9" without
the patch:

  ==13372== LEAK SUMMARY:
  ==13372==    definitely lost: 230,986 bytes in 2,325 blocks
  ==13372==    indirectly lost: 0 bytes in 0 blocks
  ==13372==      possibly lost: 98 bytes in 1 blocks
  ==13372==    still reachable: 2,259,198 bytes in 3,243 blocks
  ==13372==         suppressed: 0 bytes in 0 blocks

And with the patch applied:

  ==13375== LEAK SUMMARY:
  ==13375==    definitely lost: 65 bytes in 1 blocks
  ==13375==    indirectly lost: 0 bytes in 0 blocks
  ==13375==      possibly lost: 0 bytes in 0 blocks
  ==13375==    still reachable: 2,364,417 bytes in 3,245 blocks
  ==13375==         suppressed: 0 bytes in 0 blocks

Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
tests: modernise style: more uses of test_line_count

Prefer:

  test_line_count <OP> COUNT FILE

over:

  test $(wc -l <FILE) <OP> COUNT

(or similar usages) in several tests.

Signed-off-by: Stefano Lattarini <stefano.lattarini@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
gc: do not explode objects which will be immediately pruned

When we pack everything into one big pack with "git repack
-Ad", any unreferenced objects in to-be-deleted packs are
exploded into loose objects, with the intent that they will
be examined and possibly cleaned up by the next run of "git
prune".

Since the exploded objects will receive the mtime of the
pack from which they come, if the source pack is old, those
loose objects will end up pruned immediately. In that case,
it is much more efficient to skip the exploding step
entirely for these objects.

This patch teaches pack-objects to receive the expiration
information and avoid writing these objects out. It also
teaches "git gc" to pass the value of gc.pruneexpire to
repack (which in turn learns to pass it along to
pack-objects) so that this optimization happens
automatically during "git gc" and "git gc --auto".

Signed-off-by: Jeff King <peff@peff.net>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Fix httpd tests that broke when non-ff push advice changed

Signed-off-by: Christopher Tiwald <christiwald@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
t4052: test --stat output with --graph

Add tests which show that the width of the --prefix added by --graph
is not taken into consideration when the diff stat output width is
calculated.

Signed-off-by: Zbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl>
Signed-off-by: Lucian Poston <lucian.poston@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add output_prefix_length to diff_options

Add output_prefix_length to diff_options. Initialize the value to 0 and only
set it when graph.c:diff_output_prefix_callback() is called.

Signed-off-by: Lucian Poston <lucian.poston@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Adjust stat width calculations to take --graph output into account

The recent change to compute the width of diff --stat did not take into
consideration the output from --graph. The consequence is that when both
options are used, e.g. in 'log --stat --graph', the lines are too long.

Adjust stat width calculations to take --graph output into account.

Signed-off-by: Lucian Poston <lucian.poston@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
t4052: Adjust --graph --stat output for prefixes

Adjust tests to verify that the commit history graph tree is taken into
consideration when the diff stat output width is calculated.

Signed-off-by: Lucian Poston <lucian.poston@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
t4052: Test diff-stat output with minimum columns

When COLUMNS or --stat-width restricts the diff-stat width to near the
minimum, 26 columns, the graph_width value becomes negative. Consequently, the
graph part of diff-stat is not resized properly.

Signed-off-by: Lucian Poston <lucian.poston@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Prevent graph_width of stat width from falling below min

Update tests in t4052 fixed by this change.

Signed-off-by: Lucian Poston <lucian.poston@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
argv-array: refactor empty_argv initialization

An empty argv-array is initialized to point to a static
empty NULL-terminated array.  The original implementation
separates the actual storage of the NULL-terminator from the
pointer to the list.  This makes the exposed type a "const
char **", which nicely matches the type stored by the
argv-array.

However, this indirection means that one cannot use
empty_argv to initialize a static variable, since it is
not a constant.

Instead, we can expose empty_argv directly, as an array of
pointers. The only place we use it is in the ARGV_ARRAY_INIT
initializer, and it decays to a pointer appropriately there.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>