Commit Graph

251 Commits

Author SHA1 Message Date
Junio C Hamano
97d5165780 Merge branch 'jc/xstrfmt-null-with-prec-0' into maint
Code cleanup.

* jc/xstrfmt-null-with-prec-0:
  setup.c: do not feed NULL to "%.*s" even with precision 0
2016-05-02 14:24:14 -07:00
Junio C Hamano
8591654998 Merge branch 'jk/check-repository-format' into maint
The repository set-up sequence has been streamlined (the biggest
change is that there is no longer git_config_early()), so that we
do not attempt to look into refs/* when we know we do not have a
Git repository.

* jk/check-repository-format:
  verify_repository_format: mark messages for translation
  setup: drop repository_format_version global
  setup: unify repository version callbacks
  init: use setup.c's repo version verification
  setup: refactor repo format reading and verification
  config: drop git_config_early
  check_repository_format_gently: stop using git_config_early
  lazily load core.sharedrepository
  wrap shared_repository global in get/set accessors
  setup: document check_repository_format()
2016-05-02 14:24:04 -07:00
Junio C Hamano
24041d6be5 setup.c: do not feed NULL to "%.*s" even with precision 0
A recent update 75faa45a (replace trivial malloc + sprintf / strcpy
calls with xstrfmt, 2015-09-24) rewrote

	prepare an empty buffer
	if (len)
        	append the first len bytes of "prefix" to the buffer
	append "path" to the buffer

that computed "path", optionally prefixed by "prefix", into

	xstrfmt("%.*s%s", len, prefix, path);

However, passing a NULL pointer to the printf(3) family of functions
to format it with %s conversion, even with the precision set to 0,
i.e.

	xstrfmt("%.*s", 0, NULL)

yields undefined results, at least on some platforms.

Avoid this problem by substituting prefix with "" when len==0, as
prefix can legally be NULL in that case.  This would mimick the
intent of the original code better.

Reported-by: Tom G. Christensen <tgc@jupiterrise.com>
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-04-07 12:40:15 -07:00
Jeff King
274db840b4 verify_repository_format: mark messages for translation
These messages are human-readable and should be translated.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-03-11 15:02:24 -08:00
Jeff King
c90e5293d1 setup: drop repository_format_version global
Nobody reads this anymore, and they're not likely to; the
interesting thing is whether or not we passed
check_repository_format(), and possibly the individual
"extension" variables.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-03-11 15:02:24 -08:00
Jeff King
652f18ee87 setup: unify repository version callbacks
Once upon a time, check_repository_format_gently would parse
the config with a single callback, and that callback would
set up a bunch of global variables. But now that we have
separate workdirs, we have to be more careful. Commit
31e26eb (setup.c: support multi-checkout repo setup,
2014-11-30) introduced a reduced callback which omits some
values like core.worktree. In the "main" callback we call
the reduced one, and then add back in the missing variables.

Now that we have split the config-parsing from the munging
of the global variables, we can do it all with a single
callback, and keep all of the "are we in a separate workdir"
logic together.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-03-11 15:02:23 -08:00
Jeff King
2cc7c2c737 setup: refactor repo format reading and verification
When we want to know if we're in a git repository of
reasonable vintage, we can call check_repository_format_gently(),
which does three things:

  1. Reads the config from the .git/config file.

  2. Verifies that the version info we read is sane.

  3. Writes some global variables based on this.

There are a few things we could improve here.

One is that steps 1 and 3 happen together. So if the
verification in step 2 fails, we still clobber the global
variables. This is especially bad if we go on to try another
repository directory; we may end up with a state of mixed
config variables.

The second is there's no way to ask about the repository
version for anything besides the main repository we're in.
git-init wants to do this, and it's possible that we would
want to start doing so for submodules (e.g., to find out
which ref backend they're using).

We can improve both by splitting the first two steps into
separate functions. Now check_repository_format_gently()
calls out to steps 1 and 2, and does 3 only if step 2
succeeds.

Note that the public interface for read_repository_format()
and what check_repository_format_gently() needs from it are
not quite the same, leading us to have an extra
read_repository_format_1() helper. The extra needs from
check_repository_format_gently() will go away in a future
patch, and we can simplify this then to just the public
interface.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-03-11 15:02:23 -08:00
Jeff King
21627f9b6d check_repository_format_gently: stop using git_config_early
There's a chicken-and-egg problem with using the regular
git_config during the repository setup process. We get
around it here by using a special interface that lets us
specify the per-repo config, and avoid calling
git_pathdup().

But this interface doesn't actually make sense. It will look
in the system and per-user config, too; we definitely would
not want to accept a core.repositoryformatversion from
there.

The git_config_from_file interface is a better match, as it
lets us look at a single file.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-03-11 15:02:22 -08:00
Jeff King
ae5f67763b lazily load core.sharedrepository
The "shared_repository" config is loaded as part of
check_repository_format_version, but it's not quite like the
other values we check there. Something like
core.repositoryformatversion only makes sense in per-repo
config, but core.sharedrepository can be set in a per-user
config (e.g., to make all "git init" invocations shared by
default).

So it would make more sense as part of git_default_config.
Commit 457f06d (Introduce core.sharedrepository, 2005-12-22)
says:

  [...]the config variable is set in the function which
  checks the repository format. If this were done in
  git_default_config instead, a lot of programs would need
  to be modified to call git_config(git_default_config)
  first.

This is still the case today, but we have one extra trick up
our sleeve. Now that we have the git_configset
infrastructure, it's not so expensive for us to ask for a
single value. So we can simply lazy-load it on demand.

This should be OK to do in general. There are some problems
with loading config before setup_git_directory() is called,
but we shouldn't be accessing the value before then (if we
were, then it would already be broken, as the variable would
not have been set by check_repository_format_version!). The
trickiest caller is git-init, but it handles the values
manually itself.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-03-11 15:02:19 -08:00
Jeff King
7875acb6ec wrap shared_repository global in get/set accessors
It would be useful to control access to the global
shared_repository, so that we can lazily load its config.
The first step to doing so is to make sure all access
goes through a set of functions.

This step is purely mechanical, and should result in no
change of behavior.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-03-11 15:02:17 -08:00
Jeff King
4b0d1eebe9 setup: document check_repository_format()
This function's interface is rather enigmatic, so let's
document it further.

While we're here, let's also drop the return value. It will
always either be "0" or the function will die (consequently,
neither of its two callers bothered to check the return).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-03-11 15:02:13 -08:00
Jeff King
f1c126bd8b setup: set startup_info->have_repository more reliably
When setup_git_directory() is called, we set a flag in
startup_info to indicate we have a repository. But there are
a few other mechanisms by which we might set up a repo:

  1. When creating a new repository via init_db(), we
     transition from no-repo to being in a repo. We should
     tweak this flag at that moment.

  2. In enter_repo(), a stricter form of
     setup_git_directory() used by server-side programs, we
     check the repository format config. After doing so, we
     know we're in a repository, and can set the flag.

With these changes, library code can now reliably tell
whether we are in a repository and act accordingly. We'll
leave the "prefix" field as NULL, which is what happens when
setup_git_directory() finds there is no prefix.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-03-06 17:18:16 -08:00
Jeff King
46c3cd44d7 setup: make startup_info available everywhere
Commit a60645f (setup: remember whether repository was
found, 2010-08-05) introduced the startup_info structure,
which records some parts of the setup_git_directory()
process (notably, whether we actually found a repository or
not).

One of the uses of this data is for functions to behave
appropriately based on whether we are in a repo. But the
startup_info struct is just a pointer to storage provided by
the main program, and the only program that sets it up is
the git.c wrapper. Thus builtins have access to
startup_info, but externally linked programs do not.

Worse, library code which is accessible from both has to be
careful about accessing startup_info. This can be used to
trigger a die("BUG") via get_sha1():

	$ git fast-import <<-\EOF
	tag foo
	from HEAD:./whatever
	EOF

	fatal: BUG: startup_info struct is not initialized.

Obviously that's fairly nonsensical input to feed to
fast-import, but we should never hit a die("BUG"). And there
may be other ways to trigger it if other non-builtins
resolve sha1s.

So let's point the storage for startup_info to a static
variable in setup.c, making it available to all users of the
library code. We _could_ turn startup_info into a regular
extern struct, but doing so would mean tweaking all of the
existing use sites. So let's leave the pointer indirection
in place.  We can, however, drop any checks for NULL, as
they will always be false (and likewise, we can drop the
test covering this case, which was a rather artificial
situation using one of the test-* programs).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-03-06 17:17:37 -08:00
Junio C Hamano
11529ecec9 Merge branch 'jk/tighten-alloc'
Update various codepaths to avoid manually-counted malloc().

* jk/tighten-alloc: (22 commits)
  ewah: convert to REALLOC_ARRAY, etc
  convert ewah/bitmap code to use xmalloc
  diff_populate_gitlink: use a strbuf
  transport_anonymize_url: use xstrfmt
  git-compat-util: drop mempcpy compat code
  sequencer: simplify memory allocation of get_message
  test-path-utils: fix normalize_path_copy output buffer size
  fetch-pack: simplify add_sought_entry
  fast-import: simplify allocation in start_packfile
  write_untracked_extension: use FLEX_ALLOC helper
  prepare_{git,shell}_cmd: use argv_array
  use st_add and st_mult for allocation size computation
  convert trivial cases to FLEX_ARRAY macros
  use xmallocz to avoid size arithmetic
  convert trivial cases to ALLOC_ARRAY
  convert manual allocations to argv_array
  argv-array: add detach function
  add helpers for allocating flex-array structs
  harden REALLOC_ARRAY and xcalloc against size_t overflow
  tree-diff: catch integer overflow in combine_diff_path allocation
  ...
2016-02-26 13:37:16 -08:00
Junio C Hamano
e6a6a768ca Merge branch 'nd/dwim-wildcards-as-pathspecs'
"git show 'HEAD:Foo[BAR]Baz'" did not interpret the argument as a
rev, i.e. the object named by the the pathname with wildcard
characters in a tree object.

* nd/dwim-wildcards-as-pathspecs:
  get_sha1: don't die() on bogus search strings
  check_filename: tighten dwim-wildcard ambiguity
  checkout: reorder check_filename conditional
2016-02-24 13:25:52 -08:00
Jeff King
3733e69464 use xmallocz to avoid size arithmetic
We frequently allocate strings as xmalloc(len + 1), where
the extra 1 is for the NUL terminator. This can be done more
simply with xmallocz, which also checks for integer
overflow.

There's no case where switching xmalloc(n+1) to xmallocz(n)
is wrong; the result is the same length, and malloc made no
guarantees about what was in the buffer anyway. But in some
cases, we can stop manually placing NUL at the end of the
allocated buffer. But that's only safe if it's clear that
the contents will always fill the buffer.

In each case where this patch does so, I manually examined
the control flow, and I tried to err on the side of caution.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-22 14:51:09 -08:00
Junio C Hamano
d0a1cbccab Merge branch 'nd/do-not-move-worktree-manually'
"git worktree" had a broken code that attempted to auto-fix
possible inconsistency that results from end-users moving a
worktree to different places without telling Git (the original
repository needs to maintain backpointers to its worktrees, but
"mv" run by end-users who are not familiar with that fact will
obviously not adjust them), which actually made things worse
when triggered.

* nd/do-not-move-worktree-manually:
  worktree: stop supporting moving worktrees manually
  worktree.c: fix indentation
2016-02-10 14:20:05 -08:00
Jeff King
df714f81a7 check_filename: tighten dwim-wildcard ambiguity
When specifying both revisions and pathnames, we allow
"<rev> -- <pathspec>" to be spelled without the "--" as long
as it is not ambiguous. The original logic was something
like:

  1. Resolve each item with get_sha1(). If successful,
     we know it can be a <rev>. Verify that it _isn't_ a
     filename, using verify_non_filename(), and complain of
     ambiguity otherwise.

  2. If get_sha1() didn't succeed, make sure that it _is_
     a file, using verify_filename(). If not, complain
     that it is neither a <rev> nor a <pathspec>.

Both verify_filename() and verify_non_filename() rely on
check_filename(), which definitely said "yes, this is a
file" or "no, it is not" using lstat().

Commit 28fcc0b (pathspec: avoid the need of "--" when
wildcard is used, 2015-05-02) introduced a convenience
feature: check_filename() will consider anything with
wildcard meta-characters as a possible filename, without
even checking the filesystem.

This works well for case 2. For such a wildcard, we would
previously have died and said "it is neither". Post-28fcc0b,
we assume it's a pathspec and proceed.

But it makes some instances of case 1 worse. We may have an
extended sha1 expression that contains meta-characters
(e.g., "HEAD^{/foo.*bar}"), and we now complain that it's
also a filename, due to the wildcard characters (even though
that wildcard would not match anything in the filesystem).

One solution would be to actually expand the pathname and
see if it matches anything on the filesystem. But that's
potentially expensive, and we do not have to be so rigorous
for this DWIM magic (if you want rigor, use "--").

Instead, we can just use different rules for cases 1 and 2.
When we know something is a rev, we will complain only if it
meets a much higher standard for "this is also a file";
namely that it actually exists in the filesystem. Case 2
remains the same: we use the looser "it could be a filename"
standard introduced by 28fcc0b.

We can accomplish this by pulling the wildcard logic out of
check_filename() and putting it into verify_filename(). Its
partner verify_non_filename() does not need a change, since
check_filename() goes back to implementing the "higher
standard".

Besides these two callers of check_filename(), there is one
other: git-checkout does a similar DWIM itself. It hits this
code path only after get_sha1() has returned failure, making
it case 2, which gets the special wildcard treatment.

Note that we drop the tests in t2019 in favor of a more
complete set in t6133. t2019 was not the right place for
them (it's about refname ambiguity, not dwim parsing
ambiguity), and the second test explicitly checked for the
opposite result of the case we are fixing here (which didn't
really make any sense; as shown by the test_must_fail in the
test, it would only serve to annoy people).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-10 13:53:20 -08:00
Jeff King
ffd036b128 clean: make is_git_repository a public function
We have always had is_git_directory(), for looking at a
specific directory to see if it contains a git repo. In
0179ca7 (clean: improve performance when removing lots of
directories, 2015-06-15), we added is_git_repository() which
checks for a non-bare repository by looking at its ".git"
entry.

However, the fix in 0179ca7 needs to be applied other
places, too. Let's make this new helper globally available.
We need to give it a better name, though, to avoid confusion
with is_git_directory(). This patch does that, documents
both functions with a comment to reduce confusion, and
removes the clean-specific references in the comments.

Based-on-a-patch-by: Andreas Krey <a.krey@gmx.de>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-01-25 11:41:53 -08:00
Nguyễn Thái Ngọc Duy
618244e160 worktree: stop supporting moving worktrees manually
The current update_linked_gitdir() has a bug that can create "gitdir"
file in non-multi-worktree setup. Worse, sometimes it can write relative
path to "gitdir" file, which will not work (e.g. "git worktree list"
will display the worktree's location incorrectly)

Instead of fixing this, we step back a bit. The original design was
probably not well thought out. For now, if the user manually moves a
worktree, they have to fix up "gitdir" file manually or the worktree
will get pruned.

Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-01-22 14:28:42 -08:00
Junio C Hamano
fa46579555 Merge branch 'jk/repository-extension'
Prepare for Git on-disk repository representation to undergo
backward incompatible changes by introducing a new repository
format version "1", with an extension mechanism.

* jk/repository-extension:
  introduce "preciousObjects" repository extension
  introduce "extensions" form of core.repositoryformatversion
2015-10-26 15:55:25 -07:00
Junio C Hamano
78891795df Merge branch 'jk/war-on-sprintf'
Many allocations that is manually counted (correctly) that are
followed by strcpy/sprintf have been replaced with a less error
prone constructs such as xstrfmt.

Macintosh-specific breakage was noticed and corrected in this
reroll.

* jk/war-on-sprintf: (70 commits)
  name-rev: use strip_suffix to avoid magic numbers
  use strbuf_complete to conditionally append slash
  fsck: use for_each_loose_file_in_objdir
  Makefile: drop D_INO_IN_DIRENT build knob
  fsck: drop inode-sorting code
  convert strncpy to memcpy
  notes: document length of fanout path with a constant
  color: add color_set helper for copying raw colors
  prefer memcpy to strcpy
  help: clean up kfmclient munging
  receive-pack: simplify keep_arg computation
  avoid sprintf and strcpy with flex arrays
  use alloc_ref rather than hand-allocating "struct ref"
  color: add overflow checks for parsing colors
  drop strcpy in favor of raw sha1_to_hex
  use sha1_to_hex_r() instead of strcpy
  daemon: use cld->env_array when re-spawning
  stat_tracking_info: convert to argv_array
  http-push: use an argv_array for setup_revisions
  fetch-pack: use argv_array for index-pack / unpack-objects
  ...
2015-10-20 15:24:01 -07:00
Jeff King
75faa45ae0 replace trivial malloc + sprintf / strcpy calls with xstrfmt
It's a common pattern to do:

  foo = xmalloc(strlen(one) + strlen(two) + 1 + 1);
  sprintf(foo, "%s %s", one, two);

(or possibly some variant with strcpy()s or a more
complicated length computation).  We can switch these to use
xstrfmt, which is shorter, involves less error-prone manual
computation, and removes many sprintf and strcpy calls which
make it harder to audit the code for real buffer overflows.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-09-25 10:18:18 -07:00
Max Kirillov
11f9dd7191 path: implement common_dir handling in git_pathdup_submodule()
When submodule is a linked worktree, "git diff --submodule" and other
calls which directly access the submodule's object database do not correctly
calculate its path. Fix it by changing the git_pathdup_submodule() behavior,
to use either common or per-worktree directory.

Do it similarly as for parent repository, but ignore the GIT_COMMON_DIR
environment variable, because it would mean common directory for the parent
repository and does not make sense for submodule.

Also add test for functionality which uses this call.

Signed-off-by: Max Kirillov <max@max630.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-09-14 11:03:46 -07:00
Junio C Hamano
91d54694a4 Merge branch 'nd/fixup-linked-gitdir'
The code in "multiple-worktree" support that attempted to recover
from an inconsistent state updated an incorrect file.

* nd/fixup-linked-gitdir:
  setup: update the right file in multiple checkouts
2015-09-01 16:31:07 -07:00
Junio C Hamano
1f76a10b2d write_file(): drop caller-supplied LF from calls to create a one-liner file
All of the callsites covered by this change call write_file() or
write_file_gently() to create a one-liner file.  Drop the caller
supplied LF and let these callees to append it as necessary.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-08-25 12:49:19 -07:00
Nguyễn Thái Ngọc Duy
82fde87ff3 setup: update the right file in multiple checkouts
This code is introduced in 23af91d (prune: strategies for linked
checkouts - 2014-11-30), and it's supposed to implement this rule from
that commit's message:

 - linked checkouts are supposed to keep its location in $R/gitdir up
   to date. The use case is auto fixup after a manual checkout move.

Note the name, "$R/gitdir", not "$R/gitfile". Correct the path to be
updated accordingly.

While at there, make sure I/O errors are not silently dropped.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-08-25 09:39:08 -07:00
Junio C Hamano
12d6ce1dba write_file(): drop "fatal" parameter
All callers except three passed 1 for the "fatal" parameter to ask
this function to die upon error, but to a casual reader of the code,
it was not all obvious what that 1 meant.  Instead, split the
function into two based on a common write_file_v() that takes the
flag, introduce write_file_gently() as a new way to attempt creating
a file without dying on error, and make three callers to call it.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-08-24 13:09:02 -07:00
Junio C Hamano
54d673f25d Merge branch 'ee/clean-remove-dirs'
Replace "is this subdirectory a separate repository that should not
be touched?" check "git clean" does by checking if it has .git/HEAD
using the submodule-related code with a more optimized check.

* ee/clean-remove-dirs:
  read_gitfile_gently: fix use-after-free
  clean: improve performance when removing lots of directories
  p7300: add performance tests for clean
  t7300: add tests to document behavior of clean and nested git
  setup: sanity check file size in read_gitfile_gently
  setup: add gentle version of read_gitfile
2015-08-03 11:01:13 -07:00
Jeff King
38ae878407 read_gitfile_gently: fix use-after-free
The "dir" variable is a pointer into the "buf" array. When
we hit the cleanup_return path, the first thing we do is
free(buf); but one of the error messages prints "dir", which
will access the memory after the free.

We can fix this by reorganizing the error path a little. We
act on the fatal, error-printing conditions first, as they
want to access memory and do not care about freeing. Then we
free any memory, and finally return.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-26 09:23:08 -07:00
Jeff King
067fbd4105 introduce "preciousObjects" repository extension
If this extension is used in a repository, then no
operations should run which may drop objects from the object
storage. This can be useful if you are sharing that storage
with other repositories whose refs you cannot see.

For instance, if you do:

  $ git clone -s parent child
  $ git -C parent config extensions.preciousObjects true
  $ git -C parent config core.repositoryformatversion 1

you now have additional safety when running git in the
parent repository. Prunes and repacks will bail with an
error, and `git gc` will skip those operations (it will
continue to pack refs and do other non-object operations).
Older versions of git, when run in the repository, will
fail on every operation.

Note that we do not set the preciousObjects extension by
default when doing a "clone -s", as doing so breaks
backwards compatibility. It is a decision the user should
make explicitly.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-24 17:09:35 -07:00
Jeff King
00a09d57eb introduce "extensions" form of core.repositoryformatversion
Normally we try to avoid bumps of the whole-repository
core.repositoryformatversion field. However, it is
unavoidable if we want to safely change certain aspects of
git in a backwards-incompatible way (e.g., modifying the set
of ref tips that we must traverse to generate a list of
unreachable, safe-to-prune objects).

If we were to bump the repository version for every such
change, then any implementation understanding version `X`
would also have to understand `X-1`, `X-2`, and so forth,
even though the incompatibilities may be in orthogonal parts
of the system, and there is otherwise no reason we cannot
implement one without the other (or more importantly, that
the user cannot choose to use one feature without the other,
weighing the tradeoff in compatibility only for that
particular feature).

This patch documents the existing repositoryformatversion
strategy and introduces a new format, "1", which lets a
repository specify that it must run with an arbitrary set of
extensions. This can be used, for example:

 - to inform git that the objects should not be pruned based
   only on the reachability of the ref tips (e.g, because it
   has "clone --shared" children)

 - that the refs are stored in a format besides the usual
   "refs" and "packed-refs" directories

Because we bump to format "1", and because format "1"
requires that a running git knows about any extensions
mentioned, we know that older versions of the code will not
do something dangerous when confronted with these new
formats.

For example, if the user chooses to use database storage for
refs, they may set the "extensions.refbackend" config to
"db". Older versions of git will not understand format "1"
and bail. Versions of git which understand "1" but do not
know about "refbackend", or which know about "refbackend"
but not about the "db" backend, will refuse to run. This is
annoying, of course, but much better than the alternative of
claiming that there are no refs in the repository, or
writing to a location that other implementations will not
read.

Note that we are only defining the rules for format 1 here.
We do not ever write format 1 ourselves; it is a tool that
is meant to be used by users and future extensions to
provide safety with older implementations.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-24 17:09:08 -07:00
Junio C Hamano
103b6f9c2b Merge branch 'jk/die-on-bogus-worktree-late'
The setup code used to die when core.bare and core.worktree are set
inconsistently, even for commands that do not need working tree.

* jk/die-on-bogus-worktree-late:
  setup_git_directory: delay core.bare/core.worktree errors
2015-06-16 14:27:06 -07:00
Erik Elfström
921bdd96af setup: sanity check file size in read_gitfile_gently
read_gitfile_gently will allocate a buffer to fit the entire file that
should be read. Add a sanity check of the file size before opening to
avoid allocating a potentially huge amount of memory if we come across
a large file that someone happened to name ".git". The limit is set to
a sufficiently unreasonable size that should never be exceeded by a
genuine .git file.

Signed-off-by: Erik Elfström <erik.elfstrom@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-15 13:14:01 -07:00
Erik Elfström
a93bedada8 setup: add gentle version of read_gitfile
read_gitfile will die on most error cases. This makes it unsuitable
for speculative calls. Extract the core logic and provide a gentle
version that returns NULL on failure.

The first usecase of the new gentle version will be to probe for
submodules during git clean.

Helped-by: Junio C Hamano <gitster@pobox.com>
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Erik Elfström <erik.elfstrom@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-09 12:29:22 -07:00
Jeff King
fada767463 setup_git_directory: delay core.bare/core.worktree errors
If both core.bare and core.worktree are set, we complain
about the bogus config and die. Dying is good, because it
avoids commands running and doing damage in a potentially
incorrect setup. But dying _there_ is bad, because it means
that commands which do not even care about the work tree
cannot run. This can make repairing the situation harder:

  [setup]
  $ git config core.bare true
  $ git config core.worktree /some/path

  [OK, expected.]
  $ git status
  fatal: core.bare and core.worktree do not make sense

  [Hrm...]
  $ git config --unset core.worktree
  fatal: core.bare and core.worktree do not make sense

  [Nope...]
  $ git config --edit
  fatal: core.bare and core.worktree do not make sense

  [Gaaah.]
  $ git help config
  fatal: core.bare and core.worktree do not make sense

Instead, let's issue a warning about the bogus config when
we notice it (i.e., for all commands), but only die when the
command tries to use the work tree (by calling setup_work_tree).
So we now get:

  $ git status
  warning: core.bare and core.worktree do not make sense
  fatal: unable to set up work tree using invalid config

  $ git config --unset core.worktree
  warning: core.bare and core.worktree do not make sense

We have to update t1510 to accomodate this; it uses
symbolic-ref to check whether the configuration works or
not, but of course that command does not use the working
tree. Instead, we switch it to use `git status`, as it
requires a work-tree, does not need any special setup, and
is read-only (so a failure will not adversely affect further
tests).

In addition, we add a new test that checks the desired
behavior (i.e., that running "git config" with the bogus
config does in fact work).

Reported-by: SZEDER Gábor <szeder@ira.uka.de>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-05-29 09:27:27 -07:00
Junio C Hamano
949d16795c Merge branch 'nd/dwim-wildcards-as-pathspecs'
A heuristic to help the "git <cmd> <revs> <pathspec>" command line
convention to catch mistyped paths is to make sure all the non-rev
parameters in the later part of the command line are names of the
files in the working tree, but that means "git grep $str -- \*.c"
must always be disambiguated with "--", because nobody sane will
create a file whose name literally is asterisk-dot-see.  Loosen the
heuristic to declare that with a wildcard string the user likely
meant to give us a pathspec.

* nd/dwim-wildcards-as-pathspecs:
  pathspec: avoid the need of "--" when wildcard is used
2015-05-19 13:17:58 -07:00
Duy Nguyen
28fcc0b71a pathspec: avoid the need of "--" when wildcard is used
When "--" is lacking from the command line and a command can take
both revs and paths, the idea is if an argument can be seen as both
an extended SHA-1 and a path, then "--" is required or git refuses
to continue. It's currently implemented as:

 (1) if an argument is rev, then it must not exist in worktree

 (2) else, it must exist in worktree

 (3) else, "--" is required.

These rules work for literal paths, but when non-literal pathspec is
involved, it almost always requires the user to add "--" because it
fails (2) and (1) is really rarely met (take "*.c" for example, (1)
is met if there is a ref named "*.c").

This patch modifies the rules a bit by considering any valid (*)
wildcard pathspec "exist in worktree". The rules become:

 (1) if an arg is a rev, then it must either exist in worktree or
     not be a valid wildcard pathspec.

 (2) else, it either exists in worktree or is a wildcard pathspec

 (3) else, "--" is required.

With the new rules, "--" is not needed most of the time when
wildcard pathspec is involved.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-05-03 11:40:13 -07:00
Nguyễn Thái Ngọc Duy
23af91d102 prune: strategies for linked checkouts
(alias R=$GIT_COMMON_DIR/worktrees/<id>)

 - linked checkouts are supposed to keep its location in $R/gitdir up
   to date. The use case is auto fixup after a manual checkout move.

 - linked checkouts are supposed to update mtime of $R/gitdir. If
   $R/gitdir's mtime is older than a limit, and it points to nowhere,
   worktrees/<id> is to be pruned.

 - If $R/locked exists, worktrees/<id> is not supposed to be pruned. If
   $R/locked exists and $R/gitdir's mtime is older than a really long
   limit, warn about old unused repo.

 - "git checkout --to" is supposed to make a hard link named $R/link
   pointing to the .git file on supported file systems to help detect
   the user manually deleting the checkout. If $R/link exists and its
   link count is greated than 1, the repo is kept.

Helped-by: Marc Branchaud <marcnarc@xiplink.com>
Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Helped-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Marc Branchaud <marcnarc@xiplink.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-01 11:00:17 -08:00
Nguyễn Thái Ngọc Duy
31e26ebcb5 setup.c: support multi-checkout repo setup
The repo setup procedure is updated to detect $GIT_DIR/commondir and
set $GIT_COMMON_DIR properly.

The core.worktree is ignored when $GIT_COMMON_DIR is set. This is
because the config file is shared in multi-checkout setup, but
checkout directories _are_ different. Making core.worktree effective
in all checkouts mean it's back to a single checkout.

Helped-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-01 11:00:15 -08:00
Nguyễn Thái Ngọc Duy
e61a509a49 setup.c: detect $GIT_COMMON_DIR check_repository_format_gently()
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-01 11:00:15 -08:00
Nguyễn Thái Ngọc Duy
7d0fb0da95 setup.c: convert check_repository_format_gently to use strbuf
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-01 11:00:15 -08:00
Nguyễn Thái Ngọc Duy
4dc4e1457e setup.c: detect $GIT_COMMON_DIR in is_git_directory()
If the file "$GIT_DIR/commondir" exists, it contains the value of
$GIT_COMMON_DIR.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-01 11:00:14 -08:00
Nguyễn Thái Ngọc Duy
1d186b6f35 setup.c: convert is_git_directory() to use strbuf
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-01 11:00:14 -08:00
Junio C Hamano
f655651e09 Merge branch 'rs/strbuf-getcwd'
Reduce the use of fixed sized buffer passed to getcwd() calls
by introducing xgetcwd() helper.

* rs/strbuf-getcwd:
  use strbuf_add_absolute_path() to add absolute paths
  abspath: convert absolute_path() to strbuf
  use xgetcwd() to set $GIT_DIR
  use xgetcwd() to get the current directory or die
  wrapper: add xgetcwd()
  abspath: convert real_path_internal() to strbuf
  abspath: use strbuf_getcwd() to remember original working directory
  setup: convert setup_git_directory_gently_1 et al. to strbuf
  unix-sockets: use strbuf_getcwd()
  strbuf: add strbuf_getcwd()
2014-09-02 13:28:44 -07:00
René Scharfe
56b9f6e738 use xgetcwd() to get the current directory or die
Convert several calls of getcwd() and die() to use xgetcwd() instead.
This way we get rid of fixed-size buffers (which can be too small
depending on the used file system) and gain consistent error messages.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-08-26 11:06:06 -07:00
René Scharfe
7333ed1788 setup: convert setup_git_directory_gently_1 et al. to strbuf
Convert setup_git_directory_gently_1() and its helper functions
setup_explicit_git_dir(), setup_discovered_git_dir() and
setup_bare_git_dir() to use a struct strbuf to hold the current working
directory.  Replacing the PATH_MAX-sized buffer used before removes a
path length limition on some file systems.  The functions are converted
all in one go because they all read and write the variable cwd.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-08-26 11:06:04 -07:00
Tanay Abhra
3c8687a73e add config_set API for caching config-like files
Currently `git_config()` uses a callback mechanism and file rereads for
config values. Due to this approach, it is not uncommon for the config
files to be parsed several times during the run of a git program, with
different callbacks picking out different variables useful to themselves.

Add a `config_set`, that can be used to construct an in-memory cache for
config-like files that the caller specifies (i.e., files like `.gitmodules`,
`~/.gitconfig` etc.). Add two external functions `git_configset_get_value`
and `git_configset_get_value_multi` for querying from the config sets.
`git_configset_get_value` follows `last one wins` semantic (i.e. if there
are multiple matches for the queried key in the files of the configset the
value returned will be the last entry in `value_list`).
`git_configset_get_value_multi` returns a list of values sorted in order of
increasing priority (i.e. last match will be at the end of the list). Add
type specific query functions like `git_configset_get_bool` and similar.

Add a default `config_set`, `the_config_set` to cache all key-value pairs
read from usual config files (repo specific .git/config, user wide
~/.gitconfig, XDG config and the global /etc/gitconfig). `the_config_set`
is populated using `git_config()`.

Add two external functions `git_config_get_value` and
`git_config_get_value_multi` for querying in a non-callback manner from
`the_config_set`. Also, add type specific query functions that are
implemented as a thin wrapper around the `config_set` API.

Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-07-29 14:29:56 -07:00
Junio C Hamano
648d9c1827 Merge branch 'mw/symlinks'
A finishing touch fix to a new change already in 'master'.

* mw/symlinks:
  setup: fix windows path buffer over-stepping
2014-05-02 13:11:03 -07:00
Martin Erik Werner
6127ff63cf setup: fix windows path buffer over-stepping
Fix a buffer over-stepping issue triggered by providing an absolute path
that is similar to the work tree path.

abspath_part_inside_repo() may currently increment the path pointer by
offset_1st_component() + wtlen, which is too much, since
offset_1st_component() is a subset of wtlen.

For the *nix-style prefix '/', this does (by luck) not cause any issues,
since offset_1st_component() is 1 and there will always be a '/' or '\0'
that can "absorb" this.

In the case of DOS-style prefixes though, the offset_1st_component() is
3 and this can potentially over-step the string buffer. For example if

    work_tree = "c:/r"
    path      = "c:/rl"

Then wtlen is 4, and incrementing the path pointer by (3 + 4) would
end up 2 bytes outside a string buffer of length 6.

Similarly if

    work_tree = "c:/r"
    path      = "c:/rl/d/a"

Then (since the loop starts by also incrementing the pointer one step),
this would mean that the function would miss checking if "c:/rl/d" could
be the work_tree, arguably this is unlikely though, since it would only
be possible with symlinks on windows.

Fix this by simply avoiding to increment by offset_1st_component() and
wtlen at the same time.

Signed-off-by: Martin Erik Werner <martinerikwerner@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-04-24 13:46:13 -07:00