This fixes various problems in the new diff options code.

 - Fix --cc/-c --patch; it showed two-tree diff used internally.

 - Use "---\n" only where it matters -- that is, use it
   immediately after the commit log text when we show a
   commit log and something else before the patch text.

 - Do not output spurious extra "\n"; have an extra newline
   after the commit log text always when we have diff output and
   we are not doing oneline.

 - When running a pickaxe you need to go recursive.
Signed-off-by: NJunio C Hamano <junkio@cox.net>

setup_revisions() calls diff_setup_done() before we can set default
value for output_format.  Don't convert DIFF_FORMAT_NO_OUTPUT to 0 in
diff_setup_done(), it is useless and makes diff-tree believe no diff
format parameters were given and thus lets it reset output_format to
DIFF_FORMAT_RAW.
Signed-off-by: NTimo Hirvonen <tihirvon@gmail.com>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

Signed-off-by: NTimo Hirvonen <tihirvon@gmail.com>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

Signed-off-by: NTimo Hirvonen <tihirvon@gmail.com>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

Add msg_sep variable to struct diff_options.  msg_sep is printed after
commit message.  Default is "\n", format-patch sets it to "---\n".

This also removes the second argument from show_log() because all
callers derived it from the first argument:

    show_log(rev, rev->loginfo, ...
Signed-off-by: NTimo Hirvonen <tihirvon@gmail.com>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

Initialize output_format to 0 instead of DIFF_FORMAT_RAW so that we can see
later if any command line options changed it.  Default value is set only if
output format was not specified.
Signed-off-by: NTimo Hirvonen <tihirvon@gmail.com>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

Signed-off-by: NTimo Hirvonen <tihirvon@gmail.com>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

DIFF_FORMAT_* are now bit-flags instead of enumerated values.
Signed-off-by: NTimo Hirvonen <tihirvon@gmail.com>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

This lets you use something like this in your $GIT_DIR/config
file.

	[diff]
		color = auto

	[diff.color]
		new = blue
		old = yellow
		frag = reverse

When diff.color is set to "auto", colored diff is enabled when
the standard output is the terminal.  Other choices are "always",
and "never".  Usual boolean true/false can also be used.

The colormap entries can specify colors for the following slots:

	plain	- lines that appear in both old and new file (context)
	meta	- diff --git header and extended git diff headers
	frag	- @@ -n,m +l,k @@ lines (hunk header)
	old	- lines deleted from old file
	new	- lines added to new file

The following color names can be used:

	normal, bold, dim, l, blink, reverse, reset,
	black, red, green, yellow, blue, magenta, cyan,
	white
Signed-off-by: NJunio C Hamano <junkio@cox.net>

Signed-off-by: NTimo Hirvonen <tihirvon@gmail.com>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

Signed-off-by: NJunio C Hamano <junkio@cox.net>

This adds -b (--ignore-space-change) and -w (--ignore-all-space) flags to
diff. The main part of the patch is teaching libxdiff about it.

[jc: renamed xdl_line_match() to xdl_recmatch() since the former is used
 for different purposes in xpatchi.c which is in the parts of the upstream
 source we do not use.]
Signed-off-by: NJohannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

This patch does:

 - always reset the color _before_ printing out the newline.

   This is actually important. You (and Johannes) didn't see it, because
   it only matters if you set the background, but if you don't do this,
   you get some random and funky behaviour if you pick a color with a
   non-default background (which still potentially has problems with tabs
   etc, but less so).

 - allow people to have a different color for the "file headers"
   (DIFF_METAINFO) and for the "fragment header" (DIFF_FRAGINFO). Also,
   make a difference between "normal color" and "reset colors"

 - default to red/green for old/new lines. That's the norm, I'd think.

 - instead of that eye-popping (and eye-ball-with-a-fondue-fork-popping)
   purple color for metadata, use bold-face for file headers, and cyan for
   the frag headers. I actually prefer the "gray background" for that, but
   it only works well in xterms, so COLOR_CYAN it is..
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

ANSI C99 doesn't allow void-pointer arithmetic. This patch fixes this in
various ways. Usually the strategy that required the least changes was used.
Signed-off-by: NFlorian Forster <octo@verplant.org>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

This patch is a slightly adjusted version of Junio's patch:
http://www.gelato.unsw.edu.au/archives/git/0604/19354.html

However, instead of using a config variable, this patch makes it available
as a diff option.
Signed-off-by: NJohannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

Currently the summary is displayed after the patch.  Fix this so
that the output order is stat-summary-patch.  As a consequence of
the way this is coded, the --summary option will only actually
display summary data if combined with either the --stat or
--patch-with-stat option.
Signed-off-by: NSean Estabrooks <seanlkml@sympatico.ca>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

Signed-off-by: NSean Estabrooks <seanlkml@sympatico.ca>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

output_format == DIFFSTAT and with_stat == true does not make sense, and
the way the code is structured it causes trouble.  Avoid it.
Signed-off-by: NJunio C Hamano <junkio@cox.net>

The second parameter is not the end of string input; it is
the optional return value to retrieve where the parser stopped.
Signed-off-by: NJunio C Hamano <junkio@cox.net>

This patch touches a couple of files, because it adds options to print a
custom text just after the subject of a commit, and just after the
diffstat.

[jc: made "many dashes" used as the boundary leader into a single
 variable, to reduce the possibility of later tweaks to miscount the
 number of dashes to break it.]
Signed-off-by: NJohannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

Actually, it is a diff option now, so you can say

	git diff --check

to ask if what you are about to commit is a good patch.

[jc: this also would work for fmt-patch, but the point is that
 the check is done before making a commit.  format-patch is run
 from an already created commit, and that is too late to catch
 whitespace damaged change.]
Signed-off-by: NJohannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

When renaming leading/a/filename to leading/b/filename (and
"filename" is sufficiently long), we tried to squash the rename
to "leading/{a => b}/filename".  However, when "/a" or "/b" part
is empty, we underflowed and tried to print a substring of
length -1.
Signed-off-by: NJunio C Hamano <junkio@cox.net>

Remove the need to pipe git diff through git apply to
get the extended headers summary.
Signed-off-by: NSean Estabrooks <seanlkml@sympatico.ca>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

We used to parse "-U" and "--unified" as part of the GIT_DIFF_OPTS
environment variable, but strangely enough we would _not_ parse them as
part of the normal diff command line (where we only accepted "-u").

This adds parsing of -U and --unified, both with an optional numeric
argument. So now you can just say

	git diff --unified=5

to get a unified diff with a five-line context, instead of having to do
something silly like

	GIT_DIFF_OPTS="--unified=5" git diff -u

(that silly format does continue to still work, of course).
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

When we cut off the front of a filename to make it fit on the line, we add
a "..." in front. However, the way the "git diff" code was written, we
will never reset the prefix back to the empty string, so every single
filename afterwards will have the "..." prefix, whether appropriate or
not.

You can see this with "git diff v2.6.16.." on the current kernel tree,
since there are filenames with long names that changed there:

 [ snip snip ]
 Documentation/filesystems/vfs.txt                  |  229
 .../firmware_class/firmware_sample_driver.c        |    3
 .../firmware_sample_firmware_class.c               |    1
 ...Documentation/fujitsu/frv/kernel-ABI.txt           |  192
 ...Documentation/hwmon/w83627hf                       |    4
 [ snip snip ]

notice how the two Documentation/firmware** filenames caused the "..." to
be added, but then the later filenames don't want it, and it also screws
up the alignment of the line numbering afterwards.

Trivially fixed by moving the declaration (and initial setting) of the
"prefix" variable into the for-loop where it is used.
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

This updates the user interface and generated diff data format.

 * "diff --binary" is used to signal that we want an e-mailable
   binary patch.  It implies --full-index and -p.

 * "apply --allow-binary-replacement" acquired a short synonym
   "apply --binary".

 * After the "GIT binary patch\n" header line there is a token
   to record which binary patch mechanism was used, so that we
   can extend it later.  Currently there are two mechanisms
   defined: "literal" and "delta".  The former records the
   deflated postimage and the latter records the deflated delta
   from the preimage to postimage.

   For purely implementation convenience, I added the deflated
   length after these "literal/delta" tokens (otherwise the
   decoding side needs to guess and reallocate the buffer while
   inflating).  Improvement patches are very welcomed.
Signed-off-by: NJunio C Hamano <junkio@cox.net>

This adds "binary patch" to the diff output and teaches apply
what to do with them.

On the diff generation side, traditionally, we said "Binary
files differ\n" without giving anything other than the preimage
and postimage object name on the index line.  This was good
enough for applying a patch generated from your own repository
(very useful while rebasing), because the postimage would be
available in such a case.  However, this was not useful when the
recipient of such a patch via e-mail were to apply it, even if
the preimage was available.

This patch allows the diff to generate "binary" patch when
operating under --full-index option.  The binary patch follows
the usual extended git diff headers, and looks like this:

	"GIT binary patch\n"
	<length byte><data>"\n"
	...
	"\n"

Each line is prefixed with a "length-byte", whose value is upper
or lowercase alphabet that encodes number of bytes that the data
on the line decodes to (1..52 -- 'A' means 1, 'B' means 2, ...,
'Z' means 26, 'a' means 27, ...).  <data> is 1 or more groups of
5-byte sequence, each of which encodes up to 4 bytes in base85
encoding.  Because 52 / 4 * 5 = 65 and we have the length byte,
an output line is capped to 66 characters.  The payload is the
same diff-delta as we use in the packfiles.

On the consumption side, git-apply now can decode and apply the
binary patch when --allow-binary-replacement is given, the diff
was generated with --full-index, and the receiving repository
has the preimage blob, which is the same condition as it always
required when accepting an "Binary files differ\n" patch.
Signed-off-by: NJunio C Hamano <junkio@cox.net>

Somebody on the #git channel complained that the sha1_to_hex() thing uses
a static buffer which caused an error message to show the same hex output
twice instead of showing two different ones.

That's pretty easily rectified by making it uses a simple LRU of a few
buffers, which also allows some other users (that were aware of the buffer
re-use) to be written in a more straightforward manner.
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

The patch format shows complete rewrite as deletion of all old lines
followed by addition of all new lines.  Count lines consistenly with
that when doing diffstat.
Signed-off-by: NJunio C Hamano <junkio@cox.net>

This is the first installment to libify diff brothers.

The updated diff-files uses revision.c::setup_revisions()
infrastructure to parse its command line arguments, which means
the pathname arguments are checked more strictly than before.
The tests are adjusted to separate possibly missing paths from
the rest of arguments with double-dashes, to show the kosher
way.

As Linus pointed out, renaming diff.c to diff-lib.c was simply
stupid, so I am renaming it back.  The new diff-lib.c is to
contain pieces extracted from diff brothers.
Signed-off-by: NJunio C Hamano <junkio@cox.net>

When a verbatim rename or copy is detected, we did not show
anything on the "diff --stat" for the filepair.  This makes it
to show the rename information.
Signed-off-by: NJunio C Hamano <junkio@cox.net>

Now I am not doing any real "git-diff in C" yet, but this would
help before doing so.
Signed-off-by: NJunio C Hamano <junkio@cox.net>

Set maximum filename length for binary files so that scaling won't be
triggered and result in invalid string access.
Signed-off-by: NJonas Fonseca <fonseca@diku.dk>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

Just like "patch" format always needs recursive, "diffstat"
format does not make sense without setting recursive.
Signed-off-by: NJunio C Hamano <junkio@cox.net>

Just like "patch" format always needs recursive, "diffstat"
format does not make sense without setting recursive.
Signed-off-by: NJunio C Hamano <junkio@cox.net>

With this option, git prepends a diffstat in front of the patch.

Since I really, really do not know what a diffstat of a combined diff
("merge diff") should look like, the diffstat is not generated for these.
Signed-off-by: NJohannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

Signed-off-by: NJunio C Hamano <junkio@cox.net>

I missed that "git-diff-* --stat" spits out three-dash separator
on its own without being asked.  Remove it.

When we output commit log followed by diff, perhaps --patch-with-stat,
for downstream consumer, we _would_ want the three-dash between
the message and the diff material, but that logic belongs to the
caller, not diff generator.
Signed-off-by: NJunio C Hamano <junkio@cox.net>

Signed-off-by: NJunio C Hamano <junkio@cox.net>

... and a fix for an invalid free():
Signed-off-by: NJunio C Hamano <junkio@cox.net>