In preparation for 1.0 release, this makes the command names
consistent with others in git-*-pull family.
Signed-off-by: NJunio C Hamano <junkio@cox.net>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Clearly even Junio felt git "rename" header lines should say "from/to"
instead of "old/new", since he wrote the documentation that way.

This way it also matches "copy".

git-apply will accept both versions, at least for a while.

A "--stat" or a "--check" will just be quiet, but if
you try to apply something with no changes, that's an
error.

The documentation failed to describe "diff --git" extended diff
headers, so add some.
Signed-off-by: NJunio C Hamano <junkio@cox.net>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This adds documentation for the diffcore mechanism and explains
how numeric parameters to -B/-C/-M options affect the output,
which was left "black magic" so far.

The documentation is not connected to any of the other asciidoc
nodes yet.  Awaiting for suggestions, fixes and help from other
people.
Signed-off-by: NJunio C Hamano <junkio@cox.net>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

It's not "rename from" and "rename to", it's "rename old" and "rename new".

Which is illogical and doesn't match the "copy from/to" case, but that's
life. Maybe Junio will fix it up one of these days.

This addresses a concern raised by Jason McMullan in the mailing
list discussion.  After retrieving and storing a potentially
deltified object, pull logic tries to check and fulfil its delta
dependency.  When the pull procedure is killed at this point,
however, there was no easy way to recover by re-running pull,
since next run would have found that we already have that
deltified object and happily reported success, without really
checking its delta dependency is satisfied.

This patch introduces --recover option to git-*-pull family
which causes them to re-validate dependency of deltified objects
we are fetching.  A new test t5100-delta-pull.sh covers such a
failure mode.
Signed-off-by: NJunio C Hamano <junkio@cox.net>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This fixes three bugs in the -B heuristics.

 - Although it was advertised that the initial break criteria
   used was the same as what diffcore-rename uses, it was using
   something different.  Instead of using smaller of src and dst
   size to compare with "edit" size, (insertion and deletion),
   it was using larger of src and dst, unlike the rename/copy
   detection logic.  This caused the parameter to -B to mean
   something different from the one to -M and -C.  To compensate
   for this change, the default break score is also changed to
   match that of the default for rename/copy.

 - The code would have crashed with division by zero when trying
   to break an originally empty file.

 - Contrary to what the comment said, the algorithm was breaking
   small files, only to later merge them together.
Signed-off-by: NJunio C Hamano <junkio@cox.net>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This fixes a bug that was preventing non-default parameter to -B
option to be passed correctly; you could not give more than 50%
break score.
Signed-off-by: NJunio C Hamano <junkio@cox.net>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This fixes two bugs.

 - declaration of auto variable "cmp" was preceeded by a
   statement, causing compilation error on real C compilers;
   noticed and patch given by Yoichi Yuasa.

 - the function's calling convention was overloading its size
   parameter to mean "largest possible value means do not add
   entry", which was a bad taste.  Brought up during a
   discussion with Peter Baudis.
Signed-off-by: NJunio C Hamano <junkio@cox.net>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

We update the index only if the "--index" flag is given,
so you can actually use this as a strange kind of "patch"
program even for non-git usage. Not that you'd likely
want to, but it comes in handy for testing.

This _should_ more or less get everythign right, but as
usual I leave the testing to the usrs..

(And fix name handling for when we have an implied
create or delete event from a traditional diff).

This applies the fragments in memory, but doesn't actually
write the results out to the files yet. But we now do all the
difficult parts, the rest is just basically writing the
results out and updating the index.

Right now it requires that the fragment offsets be exact,
and it doesn't actually apply the fragment yet, but it
does find where it goes and verify the data.

Next step: actually applying the fragment changes.

You can ask to print out "raw" format (full headers, full body),
"medium" format (author and date, full body) or "short" format
(author only, condensed body).

Use "git-rev-list --pretty=short HEAD | less -S" for an example.

Somebody finally came through - Jeff Garzik gets a gold
star for writing a shortlog script for git, so that I
can do nice release announcments again.

I added name translations from the current kernel history
(and git, for that matter). Hopefully it won't grow at
nearly the same rate the BK equivalent did, since 99% of
the time git records the full name already.

Usage: just do

        git-rev-list --pretty HEAD ^LAST_HEAD | git-shortlog

or, in fact, use any of the other tools (git-diff-tree,
git-whatchanged etc) that use the default "pretty" commit format.

This makes git-rev-list use the same command line syntax to mark the
commits as git-rev-tree does, and instead of just allowing a start and
end commit, it allows an arbitrary list of "interesting" and "uninteresting"
commits.

For example, imagine that you had three branches (a, b and c) that you
are interested in, but you don't want to see stuff that already exists
in another persons three releases (x, y and z). You can do

	git-rev-list a b c ^x ^y ^z

(order doesn't matter, btw - feel free to put the uninteresting ones
first or otherwise swithc them around), and it will show all the
commits that are reachable from a/b/c but not reachable from x/y/z.

The old syntax "git-rev-list start end" would not be written as
"git-rev-list start ^end", or "git-rev-list ^end start".

There's no limit to the number of heads you can specify (unlike
git-rev-tree, which can handle a maximum of 16 heads).

This patch makes an incompatible change to the protocol used by
rpull/rpush which will let it be extended in the future without
incompatible changes.
Signed-off-by: NDaniel Barkalow <barkalow@iabervon.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

As Linus pointed out on the mailing list discussion, -B should
break a files that has many inserts even if it still keeps
enough of the original contents, so that the broken pieces can
later be matched with other files by -M or -C.  However, if such
a broken pair does not get picked up by -M or -C, we would want
to apply different criteria; namely, regardless of the amount of
new material in the result, the determination of "rewrite"
should be done by looking at the amount of original material
still left in the result.  If you still have the original 97
lines from a 100-line document, it does not matter if you add
your own 13 lines to make a 110-line document, or if you add 903
lines to make a 1000-line document.  It is not a rewrite but an
in-place edit.  On the other hand, if you did lose 97 lines from
the original, it does not matter if you added 27 lines to make a
30-line document or if you added 997 lines to make a 1000-line
document.  You did a complete rewrite in either case.

This patch introduces a post-processing phase that runs after
diffcore-rename matches up broken pairs diffcore-break creates.
The purpose of this post-processing is to pick up these broken
pieces and merge them back into in-place modifications.  For
this, the score parameter -B option takes is changed into a pair
of numbers, and it takes "-B99/80" format when fully spelled
out.  The first number is the minimum amount of "edit" (same
definition as what diffcore-rename uses, which is "sum of
deletion and insertion") that a modification needs to have to be
broken, and the second number is the minimum amount of "delete"
a surviving broken pair must have to avoid being merged back
together.  It can be abbreviated to "-B" to use default for
both, "-B9" or "-B9/" to use 90% for "edit" but default (80%)
for merge avoidance, or "-B/75" to use default (99%) "edit" and
75% for merge avoidance.
Signed-off-by: NJunio C Hamano <junkio@cox.net>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This cleans up diff_scoreopt_parse() function that is used to
parse the fractional notation -B, -C and -M option takes.  The
callers are modified to check for errors and complain.  Earlier
they silently ignored malformed input and falled back on the
default.
Signed-off-by: NJunio C Hamano <junkio@cox.net>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch updates diff documentation and usage strings:

 - clarify the semantics of -R.  It is not "output in reverse";
   rather, it is "I will feed diff backwards".  Semantically
   they are different when -C is involved.

 - describe -O in usage strings of diff-* brothers.  It was
   implemented, documented but not described in usage text.

Also it adds -O to diff-helper.  Like -S (and unlike -M/-C/-B),
this option can work on sanitized diff-raw output produced by
the diff-* brothers.  While we are at it, the call it makes to
diffcore is cleaned up to use the diffcore_std() like everybody
else, and the declaration for the low level diffcore routines
are moved from diff.h (public) to diffcore.h (private between
diff.c and diffcore backends).
Signed-off-by: NJunio C Hamano <junkio@cox.net>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Make it return copied source and insertion separately, so that
later implementation of heuristics can use them more flexibly.

This does not change the heuristics implemented in
diffcore-rename nor diffcore-break in any way.
Signed-off-by: NJunio C Hamano <junkio@cox.net>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

git-tar-tree: remove tests of long path handling out of t5000-tar-tree.sh
and make test script cope with tar programs displaying file modification
date as hh:mm (newer variants show it as hh:mm:ss).

This makes the test cover only basic functionality that is expected to
be handled even by older tar programs.  Tests for long filenames (which
require pax extended headers) can be added separately.

I ran this test successfully with GNU tar 1.13, 1.14 and 1.15.1.
Signed-off-by: NRene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

write_trailer() writes the last 10k (a full block) of the tar archive.
write_if_needed() writes out a block *if* it is full and then sets
the offset to 0.  In nine out of ten cases the messed up write_trailer()
function didn't manage to fill the block thus not writing anything at
all, truncating the archive.  I was "lucky" to hit the other case and so
my testing ran OK.
Signed-off-by: NRene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

add a simple test case.
Signed-off-by: NRene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

document difference in behaviour w/ regard to tree vs.  commit and
correct author information.
Signed-off-by: NRene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

replace open-coded variants of get_record().
Signed-off-by: NRene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Adam Kropelin points out that it wasn't all that clear
at all what the thing does. This hopefully helps a bit.

This adds sha1_file_size() helper function and uses it in the
rename/copy similarity estimator.  The helper function handles
deltified object as well.
Signed-off-by: NJunio C Hamano <junkio@cox.net>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

When a remote repository is deltified, we need to get the
objects that a deltified object we want to obtain is based upon.
The initial parts of each retrieved SHA1 file is inflated and
inspected to see if it is deltified, and its base object is
asked from the remote side when it is.  Since this partial
inflation and inspection has a small performance hit, it can
optionally be skipped by giving -d flag to git-*-pull commands.
This flag should be used only when the remote repository is
known to have no deltified objects.

Rsync transport does not have this problem since it fetches
everything the remote side has.
Signed-off-by: NJunio C Hamano <junkio@cox.net>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Ok, now I'm happier.

Functions that do many things are bad. We should basically
just parse the arguments in main(). We're not quite there
yet, but it's a step in the right direction.

People are making fun of me for being a bad speeler.

Make a separate helper for parsing the header of an object file
(really carefully) and for unpacking the rest. This means that
anybody who uses the "unpack_sha1_header()" interface can easily
look at the header and decide to unpack the rest too, without
doing any extra work.

It's for people who aren't necessarily interested in the whole
unpacked file, but do want to know the header information (size,
type, etc..)

For example, the delta code can use this to figure out whether
an object is already a delta object, and what it is a delta
against, without actually bothering to unpack all of the actual
data in the delta.

Both locally and remotely.

The core GIT repository has trees that record regular file mode
in 0664 instead of normalized 0644 pattern.  Comparing such a
tree with another tree that records the same file in 0644
pattern without content changes with git-diff-tree causes it to
feed otherwise unmodified pairs to the diff_change() routine,
which triggers a sanity check routine and barfs.  This patch
fixes the problem, along with the fix to another caller that
uses unnormalized mode bits to call diff_change() routine in a
similar way.

Without this patch, you will see "fatal error" from diff-tree
when you run git-deltafy-script on the core GIT repository
itself.
Signed-off-by: NJunio C Hamano <junkio@cox.net>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Use "git commit" instead of "git-commit-script", and talk about using
"git log" before introducing the more complex "git-whatchanged".

In short, try to make it feel a bit more normal to those poor souls
using CVS.

Do some whitspace edits too, to make the side notes stand out a bit
more.