By default, index compat macros are off from now on, because they
could hide the_index dependency.
Only those in builtin can use it.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
One of the problems with "git checkout" is that it does so many
different things and could confuse people specially when we fail to
handle ambiguation correctly.
One way to help with that is tell the user what sort of operation is
actually carried out. When switching branches, we always print
something unless --quiet, either
- "HEAD is now at ..."
- "Reset branch ..."
- "Already on ..."
- "Switched to and reset ..."
- "Switched to a new branch ..."
- "Switched to branch ..."
Checking out paths however is silent. Print something so that if we
got the user intention wrong, they won't waste too much time to find
that out. For the remaining cases of checkout we now print either
- "Checked out ... paths out of the index"
- "Checked out ... paths out of <abbrev hash>"
Since the purpose of printing this is to help disambiguate. Only do it
when "--" is missing.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we define a parse-options callback, the flags we put in the option
struct must match what the callback expects. For example, a callback
which does not handle the "unset" parameter should only be used with
PARSE_OPT_NONEG. But since the callback and the option struct are not
defined next to each other, it's easy to get this wrong (as earlier
patches in this series show).
Fortunately, the compiler can help us here: compiling with
-Wunused-parameters can show us which callbacks ignore their "unset"
parameters (and likewise, ones that ignore "arg" expect to be triggered
with PARSE_OPT_NOARG).
But after we've inspected a callback and determined that all of its
callers use the right flags, what do we do next? We'd like to silence
the compiler warning, but do so in a way that will catch any wrong calls
in the future.
We can do that by actually checking those variables and asserting that
they match our expectations. Because this is such a common pattern,
we'll introduce some helper macros. The resulting messages aren't
as descriptive as we could make them, but the file/line information from
BUG() is enough to identify the problem (and anyway, the point is that
these should never be seen).
Each of the annotated callbacks in this patch triggers
-Wunused-parameters, and was manually inspected to make sure all callers
use the correct options (so none of these BUGs should be triggerable).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Spell out all alternatives and avoid using a numerical range operator,
as it is not mentioned in CodingGuidelines and the resulting string is
still concise. Wrap them in parentheses to document clearly that the
"--stage=" part is common among them.
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
checkout-index.c needs update because if checkout->istate is NULL,
ie_match_stat() will crash. Previously this is ie_match_stat(&the_index, ..)
so it will not crash, but it is not technically correct either.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
--force option is most likely hidden from command line completion for
safety reasons. This is done by adding an extra flag
PARSE_OPT_NOCOMPLETE. Update OPT__FORCE() to accept additional
flags. Actual flag change comes later depending on individual
commands.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
`newfd` starts out negative. If we then take the lock, `newfd` will
become non-negative. We later check for exactly that property before
calling `write_locked_index()`. That is, we are simply using `newfd` as
a boolean to keep track of whether we took the lock or not. (We always
use `newfd` and `lock_file` together, so they really are mirroring each
other.)
Drop `newfd` and check with `is_lock_file_locked()` instead. While at
it, move the `static struct lock_file` into `cmd_checkout_index()` and
make it non-static. It is only used in this function, and after
076aa2cbd (tempfile: auto-allocate tempfiles on heap, 2017-09-05), we
can have lockfiles on the stack.
Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Stop including config.h by default in cache.h. Instead only include
config.h in those files which require use of the config system.
Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Callers of the hold_locked_index() function pass 0 when they want to
prepare to write a new version of the index file without wishing to
die or emit an error message when the request fails (e.g. somebody
else already held the lock), and pass 1 when they want the call to
die upon failure.
This option is called LOCK_DIE_ON_ERROR by the underlying lockfile
API, and the hold_locked_index() function translates the paramter to
LOCK_DIE_ON_ERROR when calling the hold_lock_file_for_update().
Replace these hardcoded '1' with LOCK_DIE_ON_ERROR and stop
translating. Callers other than the ones that are replaced with
this change pass '0' to the function; no behaviour change is
intended with this patch.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
Among the callers of hold_locked_index() that passes 0:
- diff.c::refresh_index_quietly() at the end of "git diff" is an
opportunistic update; it leaks the lockfile structure but it is
just before the program exits and nobody should care.
- builtin/describe.c::cmd_describe(),
builtin/commit.c::cmd_status(),
sequencer.c::read_and_refresh_cache() are all opportunistic
updates and they are OK.
- builtin/update-index.c::cmd_update_index() takes a lock upfront
but we may end up not needing to update the index (i.e. the
entries may be fully up-to-date), in which case we do not need to
issue an error upon failure to acquire the lock. We do diagnose
and die if we indeed need to update, so it is OK.
- wt-status.c::require_clean_work_tree() IS BUGGY. It asks
silence, does not check the returned value. Compare with
callsites like cmd_describe() and cmd_status() to notice that it
is wrong to call update_index_if_able() unconditionally.
Add a static initializer for struct checkout and use it throughout the
code base. It's shorter, avoids a memset(3) call and makes sure the
base_dir member is initialized to a valid (empty) string.
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We do not really expect people to use "--no-stage", but if
they do, git currently segfaults. We could instead have it
undo the effects of a previous "--stage", but this gets
tricky around the "to_tempfile" flag. We cannot simply reset
it to 0, because we don't know if it was set by a previous
"--stage=all" or an explicit "--temp" option.
We could solve this by setting a flag and resolving
to_tempfile later, but it's not worth the effort. Nobody
actually wants to use "--no-stage"; we are just trying to
fix a potential segfault here.
While we're in the area, let's improve the user-facing
messages for this option. The error string should be
translatable, and we should give some hint in the "-h"
output about what can go in the argument field.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The parsing of "--index" is done in a callback, but it does
not handle an "unset" option. We don't necessarily expect
anyone to use this, but the current behavior is to treat it
exactly like "--index", which would probably be surprising.
Instead, let's just turn it into an OPT_BOOL, and handle it
after we're done parsing. This makes "--no-index" just work
(it cancels a previous "--index").
As a bonus, this makes the logic easier to follow. The old
code opened the index during the option parsing, leaving the
reader to wonder if there was some timing issue (there
isn't; none of the other options care that we've opened it).
And then if we found that "--prefix" had been given, we had
to rollback the index. Now we can simply avoid opening it in
the first place.
Note that it might make more sense for checkout-index to
complain when "--index --prefix=foo" is given (rather than
silently ignoring "--index"), but since it has been that way
since 415e96c ([PATCH] Implement git-checkout-cache -u to
update stat information in the cache., 2005-05-15), it's
safer to leave it as-is.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We use a custom callback to parse "--prefix", but it does
not handle the "unset" case. As a result, passing
"--no-prefix" will cause a segfault.
We can fix this by switching it to an OPT_STRING, which
makes "--no-prefix" counteract a previous "--prefix". Note
that this assigns NULL, so we bump our default-case
initialization to lower in the main function.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Now that we act as a simple bool, there's no need to use a
custom callback.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It's a common pattern in our code to read paths from stdin,
separated either by newlines or NULs, and unquote as
necessary. In each of these five cases we use "nbuf" to
temporarily store the unquoted value. Let's give it the more
meaningful name "unquoted", which makes it easier to
understand the purpose of the variable.
While we're at it, let's also static-initialize all of our
strbufs. It's not wrong to call strbuf_init, but it
increases the cognitive load on the reader, who might wonder
"do we sometimes avoid initializing them? why?".
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The program by default reads LF terminated lines, with an option to
use NUL terminated records. Instead of pretending that there can be
other useful values for line_termination, use a boolean variable,
nul_term_line, to tell if NUL terminated records are used, and
switch between strbuf_getline_{lf,nul} based on it.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
As of d089ebaa (setup: sanitize absolute and funny paths in
get_pathspec(), 2008-01-28), prefix_path() always returns a
newly allocated string, so callers should free its result.
Additionally, drop the const from variables to which the result of
the prefix_path() is assigned, so they can be free()'d without
having to cast-away the constness.
Signed-off-by: Stefan Beller <sbeller@google.com>
Reviewed-by: Eric Sunshine <sunshine@sunshineco.com>
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This patch puts the usage info strings that were not already in docopt-
like format into docopt-like format, which will be a litle easier for
end users and a lot easier for translators. Changes include:
- Placing angle brackets around fill-in-the-blank parameters
- Putting dashes in multiword parameter names
- Adding spaces to [-f|--foobar] to make [-f | --foobar]
- Replacing <foobar>* with [<foobar>...]
Signed-off-by: Alex Henrie <alexhenrie24@gmail.com>
Reviewed-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
checkout-index --temp only properly prints relative paths which are
descendants of the current directory. Paths in ancestor or sibling
directories (or their children) are often printed in mangled form. For
example:
mkdir a bbb &&
>file &&
>bbb/file &&
git update-index --add file bbb/file &&
cd a &&
git checkout-index --temp ../file ../bbb/file
prints:
.merge_file_ooblek le
.merge_file_igloo0 b/file
rather than the correct:
.merge_file_ooblek ../file
.merge_file_igloo0 ../bbb/file
Internally, given the above example, checkout-index prefixes each input
argument with the name of the current directory ("a/", in this case),
and then assumes that it can simply skip forward by strlen("a/") bytes
to recover the original name. This works for files in the current
directory or its descendants, but fails for files in ancestors or
siblings (or their children) due to path normalization.
For instance, given "../file", "a/" is prepended, giving "a/../file".
Path normalization folds out "a/../", resulting in "file". Attempting
to recover the original name by skipping strlen("a/") bytes gives the
incorrect "le" rather than the desired "../file".
Fix this by taking advantage of write_name_quoted_relative() to recover
the original name properly, rather than assuming that it can be
recovered by skipping strlen(prefix) bytes.
As a bonus, this also fixes a bug in which checkout-index --temp
accessed and printed memory beyond the end-of-string. For instance,
within a subdirectory named "subdirectory", and given argument
"../file", prefixing would give "subdirectory/../file", which would
become "file" after normalization. checkout-index would then attempt to
recover the original name by skipping strlen("subdirectory/") bytes of
"file", which placed it well beyond end-of-string. Despite this error,
it often appeared to give the correct result, but only due to an
accident of implementation which left an apparently correct copy of the
path in memory following the normalized value. In particular, handed
"subdirectory/../file", in-place processing by normalize_path_copy_len()
resulted in "file\0rectory/../file". When checkout-index skipped
strlen("subdirectory/") bytes, it ended up back at "../file" and thus
appeared to give the correct answer, despite being past end-of-string.
Reported-by: Russ Cox <rsc@golang.org>
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move the interface declaration for the functions in lockfile.c from
cache.h to a new file, lockfile.h. Add #includes where necessary (and
remove some redundant includes of cache.h by files that already
include builtin.h).
Move the documentation of the lock_file state diagram from lockfile.c
to the new header file.
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Other fill_stat_cache_info() is on new entries, which should set
CE_ENTRY_ADDED in cache_changed, so we're safe.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The said function has this signature:
extern int checkout_entry(struct cache_entry *ce,
const struct checkout *state,
char *topath);
At first glance, it might appear that the caller of checkout_entry()
can specify to which path the contents are written out by the last
parameter, and it is tempting to add "const" in front of its type.
In reality, however, topath[] is to point at a buffer to store the
temporary path generated by the callchain originating from this
function, and the temporary path is always short, much shorter than
the buffer prepared by its only caller in builtin/checkout-index.c.
Document the code a bit to clarify so that future callers know how
to use the function better.
Noticed-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The --no-create was parsed with OPT_BOOLEAN, which has a counting up
logic implemented. Since b04ba2bb (parse-options: deprecate OPT_BOOLEAN,
2011-09-27) the OPT_BOOLEAN is deprecated and is only a define:
/* Deprecated synonym */
#define OPTION_BOOLEAN OPTION_COUNTUP
However the variable not_new, which can be counted up by giving
--no-create multiple times, is used to set a bit in the struct checkout
bitfield (defined in cache.h:969, declared at builtin/checkout-index.c:19):
state.not_new = not_new;
When assigning a value other than 0 or 1 to a bit, all leading digits but
the last are ignored and only the last bit is used for setting the bit
variable.
Hence the following:
# in git.git:
$ git status
# working directory clean
rm COPYING
$ git status
# deleted: COPYING
$ git checkout-index -a -n
$ git status
# deleted: COPYING
# which is expected as we're telling git to not restore or create
# files, however:
$ git checkout-index -a -n -n
$ git status
# working directory clean, COPYING is restored again!
# That's the bug, we're fixing here.
By restraining the variable not_new to a value being definitely 0 or 1
by the macro OPT_BOOL the bug is fixed.
Signed-off-by: Stefan Beller <stefanbeller@googlemail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This task emerged from b04ba2bb (parse-options: deprecate OPT_BOOLEAN,
2011-09-27). All occurrences of the respective variables have
been reviewed and none of them relied on the counting up mechanism,
but all of them were using the variable as a true boolean.
This patch does not change semantics of any command intentionally.
Signed-off-by: Stefan Beller <stefanbeller@googlemail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The first paragraph about flag order is no longer true and is
mentioned in git-checkout-index.txt. The rest is also mentioned in
git-checkout-index.txt.
Remove it and keep uptodate document in one place.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add OPT__FORCE as a helper macro in the same spirit as OPT__VERBOSE
et.al. to simplify defining -f/--force options.
Signed-off-by: Rene Scharfe <rene.scharfe@lstfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Allows better help text to be defined than "be quiet". Also make use
of the macro in a place that already had a different description. No
object code changes intended.
Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
checkout-index loads the index before parsing options. Erroring out
is counterproductive at that point if the operator is hunting for a
command to recover useful data from the broken repository.
[jn: new commit message, tests]
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The `<file>' argument is optional in both cases (the man pages are
already correct).
Signed-off-by: Štěpán Němec <stepnem@gmail.com>
Acked-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This shrinks the top-level directory a bit, and makes it much more
pleasant to use auto-completion on the thing. Instead of
[torvalds@nehalem git]$ em buil<tab>
Display all 180 possibilities? (y or n)
[torvalds@nehalem git]$ em builtin-sh
builtin-shortlog.c builtin-show-branch.c builtin-show-ref.c
builtin-shortlog.o builtin-show-branch.o builtin-show-ref.o
[torvalds@nehalem git]$ em builtin-shor<tab>
builtin-shortlog.c builtin-shortlog.o
[torvalds@nehalem git]$ em builtin-shortlog.c
you get
[torvalds@nehalem git]$ em buil<tab> [type]
builtin/ builtin.h
[torvalds@nehalem git]$ em builtin [auto-completes to]
[torvalds@nehalem git]$ em builtin/sh<tab> [type]
shortlog.c shortlog.o show-branch.c show-branch.o show-ref.c show-ref.o
[torvalds@nehalem git]$ em builtin/sho [auto-completes to]
[torvalds@nehalem git]$ em builtin/shor<tab> [type]
shortlog.c shortlog.o
[torvalds@nehalem git]$ em builtin/shortlog.c
which doesn't seem all that different, but not having that annoying
break in "Display all 180 possibilities?" is quite a relief.
NOTE! If you do this in a clean tree (no object files etc), or using an
editor that has auto-completion rules that ignores '*.o' files, you
won't see that annoying 'Display all 180 possibilities?' message - it
will just show the choices instead. I think bash has some cut-off
around 100 choices or something.
So the reason I see this is that I'm using an odd editory, and thus
don't have the rules to cut down on auto-completion. But you can
simulate that by using 'ls' instead, or something similar.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
To give OPT_FILENAME the prefix, we pass the prefix to parse_options()
which passes the prefix to parse_options_start() which sets the prefix
member of parse_opts_ctx accordingly. If there isn't a prefix in the
calling context, passing NULL will suffice.
Signed-off-by: Stephen Boyd <bebarino@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Essentially; s/type* /type */ as per the coding guidelines.
Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Many call sites use strbuf_init(&foo, 0) to initialize local
strbuf variable "foo" which has not been accessed since its
declaration. These can be replaced with a static initialization
using the STRBUF_INIT macro which is just as readable, saves a
function call, and takes up fewer lines.
Signed-off-by: Brandon Casey <casey@nrlssc.navy.mil>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
User notifications are presented as 'git cmd', and code comments
are presented as '"cmd"' or 'git's cmd', rather than 'git-cmd'.
Signed-off-by: Heikki Orsila <heikki.orsila@iki.fi>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This is a mechanical conversion of all '*.c' files with:
s/((?:die|error|warning)\("git)-(\S+:)/$1 $2/;
The result was manually inspected and no false positive was found.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When you misuse a git command, you are shown the usage string.
But this is currently shown in the dashed form. So if you just
copy what you see, it will not work, when the dashed form
is no longer supported.
This patch makes git commands show the dash-less version.
For shell scripts that do not specify OPTIONS_SPEC, git-sh-setup.sh
generates a dash-less usage string now.
Signed-off-by: Stephan Beyer <s-beyer@gmx.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
git_config() only had a function parameter, but no callback data
parameter. This assumes that all callback functions only modify
global variables.
With this patch, every callback gets a void * parameter, and it is hoped
that this will help the libification effort.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* quote_c_style works on a strbuf instead of a wild buffer.
* quote_c_style is now clever enough to not add double quotes if not needed.
* write_name_quoted inherits those advantages, but also take a different
set of arguments. Now instead of asking for quotes or not, you pass a
"terminator". If it's \0 then we assume you don't want to escape, else C
escaping is performed. In any case, the terminator is also appended to the
stream. It also no longer takes the prefix/prefix_len arguments, as it's
seldomly used, and makes some optimizations harder.
* write_name_quotedpfx is created to work like write_name_quoted and take
the prefix/prefix_len arguments.
Thanks to those API changes, diff.c has somehow lost weight, thanks to the
removal of functions that were wrappers around the old write_name_quoted
trying to give it a semantics like the new one, but performing a lot of
allocations for this goal. Now we always write directly to the stream, no
intermediate allocation is performed.
As a side effect of the refactor in builtin-apply.c, the length of the bar
graphs in diffstats are not affected anymore by the fact that the path was
clipped.
Signed-off-by: Pierre Habouzit <madcoder@debian.org>
If the gain is not obvious in the diffstat, the resulting code is more
readable, _and_ in checkout-index/update-index we now reuse the same buffer
to unquote strings instead of always freeing/mallocing.
This also is more coherent with the next patch that reworks quoting
functions.
The quoting function is also made more efficient scanning for backslashes
and treating portions of strings without a backslash at once.
Signed-off-by: Pierre Habouzit <madcoder@debian.org>
read_line is now strbuf_getline, and is a first class citizen, it returns 0
when reading a line worked, EOF else.
The ->eof marker was used non-locally by fast-import.c, mimic the same
behaviour using a static int in "read_next_command", that now returns -1 on
EOF, and avoids to call strbuf_getline when it's in EOF state.
Also no longer automagically strbuf_release the buffer, it's counter
intuitive and breaks fast-import in a very subtle way.
Note: being at EOF implies that command_buf.len == 0.
Signed-off-by: Pierre Habouzit <madcoder@debian.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Pierre Habouzit <madcoder@debian.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* Add strbuf_rtrim to remove trailing spaces.
* Add strbuf_insert to insert data at a given position.
* Off-by one fix in strbuf_addf: strbuf_avail() does not counts the final
\0 so the overflow test for snprintf is the strict comparison. This is
not critical as the growth mechanism chosen will always allocate _more_
memory than asked, so the second test will not fail. It's some kind of
miracle though.
* Add size extension hints for strbuf_init and strbuf_read. If 0, default
applies, else:
+ initial buffer has the given size for strbuf_init.
+ first growth checks it has at least this size rather than the
default 8192.
Signed-off-by: Pierre Habouzit <madcoder@debian.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Make every builtin-*.c file #include "builtin.h".
Also takes care of some declaration/definition mismatches.
Signed-off-by: Peter Hagervall <hager@cs.umu.se>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When defined, this allows plumbing commands that update the
index (add, apply, checkout-index, merge-recursive, mv,
read-tree, rm, update-index, and write-tree) to write their
resulting index to an alternative index file while holding a
lock to the original index file. With this, git-commit that
jumps the index does not have to make an extra copy of the index
file, and more importantly, it can do the update while holding
the lock on the index.
However, I think the interface to let an environment variable
specify the output is a mistake, as shown in the documentation.
If a curious user has the environment variable set to something
other than the file GIT_INDEX_FILE points at, almost everything
will break. This should instead be a command line parameter to
tell these plumbing commands to write the result in the named
file, to prevent stupid mistakes.
Signed-off-by: Junio C Hamano <junkio@cox.net>
Nguyễn Thái Ngọc Duy