* js/read-tree: (107 commits)
read-tree: move merge functions to the library
read-trees: refactor the unpack_trees() part
tar-tree: illustrate an obscure feature better
git.c: allow alias expansion without a git directory
setup_git_directory_gently: do not barf when GIT_DIR is given.
Build on Debian GNU/kFreeBSD
Call setup_git_directory() much earlier
Call setup_git_directory() early
Display an error from update-ref if target ref name is invalid.
Fix http-fetch
t4103: fix binary patch application test.
git-apply -R: binary patches are irreversible for now.
Teach git-apply about '-R'
Makefile: ssh-pull.o depends on ssh-fetch.c
log and diff family: honor config even from subdirectories
git-reset: detect update-ref error and report it.
lost-found: use fsck-objects --full
Teach git-http-fetch the --stdin switch
Teach git-local-fetch the --stdin switch
Make pull() support fetching multiple targets at once
...
This also moves add_file_to_index() to read-cache.c. Oh, and while
touching builtin-add.c, it also removes a duplicate git_config() call.
Signed-off-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Junio C Hamano <junkio@cox.net>
This backports the pieces that are not uncooked from the merge-recursive
WIP we have seen earlier, to be used in git-mv rewritten in C.
Signed-off-by: Junio C Hamano <junkio@cox.net>
The pack-file format is slightly different from the traditional git
object format, in that it has a much denser binary header encoding.
The traditional format uses an ASCII string with type and length
information, which is somewhat wasteful.
A new object format starts with uncompressed binary header
followed by compressed payload -- this will allow us later to
copy the payload straight to packfiles.
Obviously they cannot be read by older versions of git, so for
now new object files are created with the traditional format.
core.legacyheaders configuration item, when set to false makes
the code write in new format for people to experiment with.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
This is just an update for people being interested. Alex and me were
busy with that project for a few days now. While it has progressed nicely,
there are quite a couple TODOs in merge-recursive.c, just search for "TODO".
For impatient people: yes, it passes all the tests, and yes, according
to the evil test Alex did, it is faster than the Python script.
But no, it is not yet finished. Biggest points are:
- there are still three external calls
- in the end, it should not be necessary to write the index more than once
(just before exiting)
- a lot of things can be refactored to make the code easier and shorter
BTW we cannot just plug in git-merge-tree yet, because git-merge-tree
does not handle renames at all.
This patch is meant for testing, and as such,
- it compile the program to git-merge-recur
- it adjusts the scripts and tests to use git-merge-recur instead of
git-merge-recursive
- it provides "TEST", a script to execute the tests regarding -recursive
- it inlines the changes to read-cache.c (read_cache_from(), discard_cache()
and refresh_cache_entry())
Brought to you by Alex Riesen and Dscho
Signed-off-by: Junio C Hamano <junkio@cox.net>
Nobody else uses them, and I'm going to start changing them.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
This allows you to say:
git -p diff v2.6.16-rc5..
and the command pipes the output of any git command to your pager.
[jc: this resurrects a month old RFC patch with improvement
suggested by Linus to call it --paginate instead of --less.]
Signed-off-by: Junio C Hamano <junkio@cox.net>
This makes git-peek-remote able to basically do everything that
git-ls-remote does (but obviously just for the native protocol, so no
http[s]: or rsync: support).
The default behaviour is the same, but you can now give a mixture of
"--refs", "--tags" and "--heads" flags, where "--refs" forces
git-peek-remote to only show real refs (ie none of the fakey tag lookups,
but also not the special pseudo-refs like HEAD and MERGE_HEAD).
The "--tags" and "--heads" flags respectively limit the output to just
regular tags and heads, of course.
You can still also ask to limit them by name too.
You can combine the flags, so
git peek-remote --refs --tags .
will show all local _true_ tags, without the generated tag lookups
(compare the output without the "--refs" flag).
And "--tags --heads" will show both tags and heads, but will avoid (for
example) any special refs outside of the standard locations.
I'm also planning on adding a "--ignore-local" flag that allows us to ask
it to ignore any refs that we already have in the local tree, but that's
an independent thing.
All this is obviously gearing up to making "git fetch" cheaper.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
With the change in default, "git add ." on kernel dir is about
twice as fast as before, with only minimal (0.5%) change in
object size. The speed difference is even more noticeable
when committing large files, which is now up to 8 times faster.
The configurability is through setting core.compression = [-1..9]
which maps to the zlib constants; -1 is the default, 0 is no
compression, and 1..9 are various speed/size tradeoffs, 9
being slowest.
Signed-off-by: Joachim B Haga (cjhaga@fys.uio.no)
Acked-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio 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: Junio C Hamano <junkio@cox.net>
This cleans up the use of safe_strncpy() even more. Since it has the
same semantics as strlcpy() use this name instead. Also move the
definition from inside path.c to its own file compat/strlcpy.c, and use
it conditionally at compile time, since some platforms already has
strlcpy(). It's included in the same way as compat/setenv.c.
Signed-off-by: Peter Eriksen <s022018@student.dtu.dk>
Signed-off-by: Junio C Hamano <junkio@cox.net>
This implements a protocol extension between fetch-pack and
upload-pack to allow stderr stream from upload-pack (primarily
used for the progress bar display) to be passed back.
Signed-off-by: Junio C Hamano <junkio@cox.net>
This creates a simple specialized object allocator for basic
objects.
This avoids wasting space with malloc overhead (metadata and
extra alignment), since the specialized allocator knows the
alignment, and that objects, once allocated, are never freed.
It also allows us to track some basic statistics about object
allocations. For example, for the mozilla import, it shows
object usage as follows:
blobs: 627629 (14710 kB)
trees: 1119035 (34969 kB)
commits: 196423 (8440 kB)
tags: 1336 (46 kB)
and the simpler allocator shaves off about 2.5% off the memory
footprint off a "git-rev-list --all --objects", and is a bit
faster too.
[ Side note: this concludes the series of "save memory in object storage".
The thing is, there simply isn't much more to be saved on the objects.
Doing "git-rev-list --all --objects" on the mozilla archive has a final
total RSS of 131498 pages for me: that's about 513MB. Of that, the
object overhead is now just 56MB, the rest is going somewhere else (put
another way: the fact that this patch shaves off 2.5% of the total
memory overhead, considering that objects are now not much more than 10%
of the total shows how big the wasted space really was: this makes
object allocations much more memory- and time-efficient).
I haven't looked at where the rest is, but I suspect the bulk of it is
just the pack-file loading. It may be that we should pack the tree
objects separately from the blob objects: for git-rev-list --objects, we
don't actually ever need to even look at the blobs, but since trees and
blobs are interspersed in the pack-file, we end up not being dense in
the tree accesses, so we end up looking at more pages than we strictly
need to.
So with a 535MB pack-file, it's entirely possible - even likely - that
most of the remaining RSS is just the mmap of the pack-file itself. We
don't need to map in _all_ of it, but we do end up mapping a fair
amount. ]
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
This enhances core.sharedrepository to have additionally
specify that read and exec permissions to be given to others as
well. It is useful when serving a repository via gitweb and
git-daemon that runs as a user outside the project group.
The configuration item can take the following values:
[core]
sharedrepository ; the same as "group"
sharedrepository = true ; ditto
sharedrepository = 1 ; ditto
sharedrepository = group ; allow rwx to group
sharedrepository = all ; allow rwx to group, allow rx to other
sharedrepository = umask ; not shared - use umask
It also extends "git init-db" to take "--shared=all" and friends
from the command line.
Signed-off-by: Junio C Hamano <junkio@cox.net>
The framework to create lockfiles that are removed at exit is
first used to reliably write the index file, but it is
applicable to other things, so stop calling it "cache_file".
This also rewords a few remaining error message that called the
index file "cache file".
Signed-off-by: Junio C Hamano <junkio@cox.net>
* sp/reflog:
fetch.c: do not pass uninitialized lock to unlock_ref().
Test that git-branch -l works.
Verify git-commit provides a reflog message.
Enable ref log creation in git checkout -b.
Create/delete branch ref logs.
Include ref log detail in commit, reset, etc.
Change order of -m option to update-ref.
Correct force_write bug in refs.c
Change 'master@noon' syntax to 'master@{noon}'.
Log ref updates made by fetch.
Force writing ref if it doesn't exist.
Added logs/ directory to repository layout.
General ref log reading improvements.
Fix ref log parsing so it works properly.
Support 'master@2 hours ago' syntax
Log ref updates to logs/refs/<ref>
Convert update-ref to use ref_lock API.
Improve abstraction of ref lock/write.
* jc/cache-tree: (26 commits)
builtin-rm: squelch compiler warnings.
git-write-tree writes garbage on sparc64
Fix crash when reading the empty tree
fsck-objects: do not segfault on missing tree in cache-tree
cache-tree: a bit more debugging support.
read-tree: invalidate cache-tree entry when a new index entry is added.
Fix test-dump-cache-tree in one-tree disappeared case.
fsck-objects: mark objects reachable from cache-tree
cache-tree: replace a sscanf() by two strtol() calls
cache-tree.c: typefix
test-dump-cache-tree: validate the cached data as well.
cache_tree_update: give an option to update cache-tree only.
read-tree: teach 1-way merege and plain read to prime cache-tree.
read-tree: teach 1 and 2 way merges about cache-tree.
update-index: when --unresolve, smudge the relevant cache-tree entries.
test-dump-cache-tree: report number of subtrees.
cache-tree: sort the subtree entries.
Teach fsck-objects about cache-tree.
index: make the index file format extensible.
cache-tree: protect against "git prune".
...
Conflicts:
Makefile, builtin.h, git.c: resolved the same way as in next.
* master: (90 commits)
fetch.c: remove an unused variable and dead code.
Clean up sha1 file writing
Builtin git-cat-file
builtin format-patch: squelch content-type for 7-bit ASCII
CMIT_FMT_EMAIL: Q-encode Subject: and display-name part of From: fields.
add more informative error messages to git-mktag
remove the artificial restriction tagsize < 8kb
git-rebase: use canonical A..B syntax to format-patch
git-format-patch: now built-in.
fmt-patch: Support --attach
fmt-patch: understand old <his> notation
Teach fmt-patch about --keep-subject
Teach fmt-patch about --numbered
fmt-patch: implement -o <dir>
fmt-patch: output file names to stdout
Teach fmt-patch to write individual files.
built-in tar-tree and remote tar-tree
Builtin git-diff-files, git-diff-index, git-diff-stages, and git-diff-tree.
Builtin git-show-branch.
Builtin git-apply.
...
This makes "git format-patch" a built-in.
* js/fmt-patch:
git-rebase: use canonical A..B syntax to format-patch
git-format-patch: now built-in.
fmt-patch: Support --attach
fmt-patch: understand old <his> notation
Teach fmt-patch about --keep-subject
Teach fmt-patch about --numbered
fmt-patch: implement -o <dir>
fmt-patch: output file names to stdout
Teach fmt-patch to write individual files.
Use RFC2822 dates from "git fmt-patch".
git-fmt-patch: thinkofix to show [PATCH] properly.
rename internal format-patch wip
Minor tweak on subject line in --pretty=email
Tentative built-in format-patch.
This makes 'git add' and 'git rm' built-ins.
* lt/dirwalk:
Add builtin "git rm" command
Move pathspec matching from builtin-add.c into dir.c
Prevent bogus paths from being added to the index.
builtin-add: fix unmatched pathspec warnings.
Remove old "git-add.sh" remnants
builtin-add: warn on unmatched pathspecs
Do "git add" as a builtin
Clean up git-ls-file directory walking library interface
libify git-ls-files directory traversal
* master: (119 commits)
diff family: add --check option
Document that "git add" only adds non-ignored files.
Add a conversion tool to migrate remote information into the config
fetch, pull: ask config for remote information
Fix build procedure for builtin-init-db
read-tree -m -u: do not overwrite or remove untracked working tree files.
apply --cached: do not check newly added file in the working tree
Implement a --dry-run option to git-quiltimport
Implement git-quiltimport
Revert "builtin-grep: workaround for non GNU grep."
builtin-grep: workaround for non GNU grep.
builtin-grep: workaround for non GNU grep.
git-am: use apply --cached
apply --cached: apply a patch without using working tree.
apply --numstat: show new name, not old name.
Documentation/Makefile: create tarballs for the man pages and html files
Allow pickaxe and diff-filter options to be used by git log.
Libify the index refresh logic
Builtin git-init-db
Remove unnecessary local in get_ref_sha1.
...
This commit is what this branch is all about. It records the
evil merge needed to adjust built-in git-add and git-rm for
the cache-tree extension.
* lt/dirwalk:
Add builtin "git rm" command
Move pathspec matching from builtin-add.c into dir.c
Prevent bogus paths from being added to the index.
builtin-add: fix unmatched pathspec warnings.
Remove old "git-add.sh" remnants
builtin-add: warn on unmatched pathspecs
Do "git add" as a builtin
Clean up git-ls-file directory walking library interface
libify git-ls-files directory traversal
Conflicts:
Makefile
builtin.h
git.c
update-index.c
* jc/cache-tree: (24 commits)
Fix crash when reading the empty tree
fsck-objects: do not segfault on missing tree in cache-tree
cache-tree: a bit more debugging support.
read-tree: invalidate cache-tree entry when a new index entry is added.
Fix test-dump-cache-tree in one-tree disappeared case.
fsck-objects: mark objects reachable from cache-tree
cache-tree: replace a sscanf() by two strtol() calls
cache-tree.c: typefix
test-dump-cache-tree: validate the cached data as well.
cache_tree_update: give an option to update cache-tree only.
read-tree: teach 1-way merege and plain read to prime cache-tree.
read-tree: teach 1 and 2 way merges about cache-tree.
update-index: when --unresolve, smudge the relevant cache-tree entries.
test-dump-cache-tree: report number of subtrees.
cache-tree: sort the subtree entries.
Teach fsck-objects about cache-tree.
index: make the index file format extensible.
cache-tree: protect against "git prune".
Add test-dump-cache-tree
Use cache-tree in update-index.
...
This cleans up and libifies the "git update-index --[really-]refresh"
functionality. This will be eventually required for eventually doing the
"commit" and "status" commands as built-ins.
It really just moves "refresh_index()" from update-index.c to
read-cache.c, but it also has to change the calling convention so that the
function uses a "unsigned int flags" argument instead of various static
flags variables for passing down the information about whether to be quiet
or not, and allow unmerged entries etc.
That actually cleans up update-index.c too, since it turns out that all
those flags were really specific to that one function of the index update,
so they shouldn't have had file-scope visibility even before.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
An earlier patch from Shawn Pearce dependes on a change that is
only in "next". I do not want to make this series hostage to
the yet-to-graduate js/fmt-patch branch, but let's try fixing it
by merging the early parts of the branch to see what happens.
Right now, 'sp/reflog' will not be in "next" for now, so I won't
have to regret this -- if this merge causes problem down the road
merging I can always rebuild the topic branch ;-).
With this one, it's now a fatal error to try to add a pathname
that cannot be added with "git add", i.e.
[torvalds@g5 git]$ git add .git/config
fatal: unable to add .git/config to index
and
[torvalds@g5 git]$ git add foo/../bar
fatal: unable to add foo/../bar to index
instead of the old "Ignoring path xyz" warning that would end up
silently succeeding on any other paths.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
If config parameter core.logAllRefUpdates is true or the log
file already exists then append a line to ".git/logs/refs/<ref>"
whenever git-update-ref <ref> is executed. Each log line contains
the following information:
oldsha1 <SP> newsha1 <SP> committer <LF>
where committer is the current user, date, time and timezone in
the standard GIT ident format. If the caller is unable to append
to the log file then git-update-ref will fail without updating <ref>.
An optional message may be included in the log line with the -m flag.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
* master: (109 commits)
t1300-repo-config: two new config parsing tests.
Another config file parsing fix.
update-index: plug memory leak from prefix_path()
checkout-index: plug memory leak from prefix_path()
update-index --unresolve: work from a subdirectory.
pack-object: squelch eye-candy on non-tty
core.prefersymlinkrefs: use symlinks for .git/HEAD
repo-config: trim white-space before comment
Fix for config file section parsing.
Clarify git-cherry documentation.
Update git-unpack-objects documentation.
Fix up docs where "--" isn't displayed correctly.
Several trivial documentation touch ups.
git-svn 1.0.0
git-svn: documentation updates
delta: stricter constness
Makefile: do not link rev-list any specially.
builtin-push: --all and --tags _are_ explicit refspecs
builtin-log/whatchanged/show: make them official.
show-branch: omit uninteresting merges.
...
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: Junio 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: Junio C Hamano <junkio@cox.net>
When inspecting a project whose build infrastructure used to
assume that .git/HEAD is a symlink ref, core.prefersymlinkrefs
in the config file of such a project would help to bisect its
history.
Signed-off-by: Junio C Hamano <junkio@cox.net>
Still Work-in-progress git fmt-patch (should it be known as
format-patch-ng?) is matched with the fix made by Huw Davies
in 262a6ef76a commit to use
RFC2822 date format.
Signed-off-by: Junio C Hamano <junkio@cox.net>
* master:
t0000-basic: more commit-tree tests.
commit-tree.c: check_valid() microoptimization.
Fix filename verification when in a subdirectory
rebase: typofix.
socksetup: don't return on set_reuse_addr() error
If you don't have a "--" marker, then:
- all of the arguments we are going to assume are pathspecs
must exist in the working tree.
- none of the arguments we parsed as revisions could be
interpreted as a filename.
so that there really isn't any possibility of confusion in case
somebody does have a revision that looks like a pathname too.
The former rule has been in effect; this implements the latter.
Signed-off-by: Junio C Hamano <junkio@cox.net>
When we are in a subdirectory of a git archive, we need to take the prefix
of that subdirectory into accoung when we verify filename arguments.
Noted by Matthias Lederhofer
This also uses the improved error reporting for all the other git commands
that use the revision parsing interfaces, not just git-rev-parse. Also, it
makes the error reporting for mixed filenames and argument flags clearer
(you cannot put flags after the start of the pathname list).
[jc: with fix to a trivial typo noticed by Timo Hirvonen]
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
read_cache_1() and write_cache_1() takes an extra parameter
*sha1 that returns the checksum of the index file when non-NULL.
Signed-off-by: Junio C Hamano <junkio@cox.net>
Introduce tree-walk.[ch] and move "struct tree_desc" and
associated functions from various places.
Rename DIFF_FILE_CANON_MODE(mode) macro to canon_mode(mode) and
move it to cache.h. This macro returns the canonicalized
st_mode value in the host byte order for files, symlinks and
directories -- to be compared with a tree_desc entry.
create_ce_mode(mode) in cache.h is similar but is intended to be
used for index entries (so it does not work for directories) and
returns the value in the network byte order.
Signed-off-by: Junio C Hamano <junkio@cox.net>
Sometimes it is convient for a Porcelain to be able to checkout all
unmerged files in all stages so that an external merge tool can be
executed by the Porcelain or the end-user. Using git-unpack-file
on each stage individually incurs a rather high penalty due to the
need to fork for each file version obtained. git-checkout-index -a
--stage=all will now do the same thing, but faster.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
* lt/rev-list:
setup_revisions(): handle -n<n> and -<n> internally.
git-log (internal): more options.
git-log (internal): add approxidate.
Rip out merge-order and make "git log <paths>..." work again.
Tie it all together: "git log"
Introduce trivial new pager.c helper infrastructure
git-rev-list libification: rev-list walking
Splitting rev-list into revisions lib, end of beginning.
rev-list split: minimum fixup.
First cut at libifying revlist generation
This introduces the new function
void setup_pager(void);
to set up output to be written through a pager applocation.
All in preparation for doing the simple scripts in C.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
The new configuration option apply.whitespace can take one of
"warn", "error", "error-all", or "strip". When git-apply is run
to apply the patch to the index, they are used as the default
value if there is no command line --whitespace option.
Andrew can now tell people who feed him git trees to update to
this version and say:
git repo-config apply.whitespace error
Signed-off-by: Junio C Hamano <junkio@cox.net>
- Fix -Wundef -Wold-style-definition warnings
- Make pll_free() static
[jc: original patch by Timo had another unrelated bits:
- Use setenv() instead of putenv()
I'm postponing that part for now.]
Signed-off-by: Timo Hirvonen <tihirvon@gmail.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>
* jc/nostat:
cache_name_compare() compares name and stage, nothing else.
"assume unchanged" git: documentation.
ls-files: split "show-valid-bit" into a different option.
"Assume unchanged" git: --really-refresh fix.
ls-files: debugging aid for CE_VALID changes.
"Assume unchanged" git: do not set CE_VALID with --refresh
"Assume unchanged" git
Previous one warned people upfront to encourage fixing their
environment early, but some people just use repositories and git
tools read-only without making any changes, and in such a case
there is not much point insisting on them having a usable ident.
This round attempts to move the error until either "git-var"
asks for the ident explicitly or "commit-tree" wants to use it.
Signed-off-by: Junio C Hamano <junkio@cox.net>