Commit Graph

233 Commits

Author SHA1 Message Date
Junio C Hamano
8d7fefaac4 Merge branch 'ar/unconfuse-three-dots'
Ancient part of codebase still shows dots after an abbreviated
object name just to show that it is not a full object name, but
these ellipses are confusing to people who newly discovered Git
who are used to seeing abbreviated object names and find them
confusing with the range syntax.

* ar/unconfuse-three-dots:
  t2020: test variations that matter
  t4013: test new output from diff --abbrev --raw
  diff: diff_aligned_abbrev: remove ellipsis after abbreviated SHA-1 value
  t4013: prepare for upcoming "diff --raw --abbrev" output format change
  checkout: describe_detached_head: remove ellipsis after committish
  print_sha1_ellipsis: introduce helper
  Documentation: user-manual: limit usage of ellipsis
  Documentation: revisions: fix typo: "three dot" ---> "three-dot" (in line with "two-dot").
2017-12-19 11:33:58 -08:00
Ann T Ropea
a2cd709de3 print_sha1_ellipsis: introduce helper
Introduce a helper print_sha1_ellipsis() that pays attention to the
GIT_PRINT_SHA1_ELLIPSIS environment variable, and prepare the tests to
unconditionally set it for the test pieces that will be broken once the code
stops showing the extra dots by default.

The removal of these dots is merely a plan at this step and has not happened
yet but soon will.

Document GIT_PRINT_SHA1_ELLIPSIS.

Signed-off-by: Ann T Ropea <bedhanger@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-12-04 08:25:35 -08:00
Junio C Hamano
e05336bdda Merge branch 'bp/fsmonitor'
We learned to talk to watchman to speed up "git status" and other
operations that need to see which paths have been modified.

* bp/fsmonitor:
  fsmonitor: preserve utf8 filenames in fsmonitor-watchman log
  fsmonitor: read entirety of watchman output
  fsmonitor: MINGW support for watchman integration
  fsmonitor: add a performance test
  fsmonitor: add a sample integration script for Watchman
  fsmonitor: add test cases for fsmonitor extension
  split-index: disable the fsmonitor extension when running the split index test
  fsmonitor: add a test tool to dump the index extension
  update-index: add fsmonitor support to update-index
  ls-files: Add support in ls-files to display the fsmonitor valid bit
  fsmonitor: add documentation for the fsmonitor extension.
  fsmonitor: teach git to optionally utilize a file system monitor to speed up detecting new or changed files.
  update-index: add a new --force-write-index option
  preload-index: add override to enable testing preload-index
  bswap: add 64 bit endianness helper get_be64
2017-11-21 14:07:50 +09:00
Junio C Hamano
d4e93836a6 Merge branch 'jk/no-optional-locks'
Some commands (most notably "git status") makes an opportunistic
update when performing a read-only operation to help optimize later
operations in the same repository.  The new "--no-optional-locks"
option can be passed to Git to disable them.

* jk/no-optional-locks:
  git: add --no-optional-locks option
2017-10-03 15:42:49 +09:00
Ben Peart
883e248b8a fsmonitor: teach git to optionally utilize a file system monitor to speed up detecting new or changed files.
When the index is read from disk, the fsmonitor index extension is used
to flag the last known potentially dirty index entries. The registered
core.fsmonitor command is called with the time the index was last
updated and returns the list of files changed since that time. This list
is used to flag any additional dirty cache entries and untracked cache
directories.

We can then use this valid state to speed up preload_index(),
ie_match_stat(), and refresh_cache_ent() as they do not need to lstat()
files to detect potential changes for those entries marked
CE_FSMONITOR_VALID.

In addition, if the untracked cache is turned on valid_cached_dir() can
skip checking directories for new or changed files as fsmonitor will
invalidate the cache only for those directories that have been
identified as having potential changes.

To keep the CE_FSMONITOR_VALID state accurate during git operations;
when git updates a cache entry to match the current state on disk,
it will now set the CE_FSMONITOR_VALID bit.

Inversely, anytime git changes a cache entry, the CE_FSMONITOR_VALID bit
is cleared and the corresponding untracked cache directory is marked
invalid.

Signed-off-by: Ben Peart <benpeart@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-01 17:23:01 +09:00
Jeff King
27344d6a6c git: add --no-optional-locks option
Some tools like IDEs or fancy editors may periodically run
commands like "git status" in the background to keep track
of the state of the repository. Some of these commands may
refresh the index and write out the result in an
opportunistic way: if they can get the index lock, then they
update the on-disk index with any updates they find. And if
not, then their in-core refresh is lost and just has to be
recomputed by the next caller.

But taking the index lock may conflict with other operations
in the repository. Especially ones that the user is doing
themselves, which _aren't_ opportunistic. In other words,
"git status" knows how to back off when somebody else is
holding the lock, but other commands don't know that status
would be happy to drop the lock if somebody else wanted it.

There are a couple possible solutions:

  1. Have some kind of "pseudo-lock" that allows other
     commands to tell status that they want the lock.

     This is likely to be complicated and error-prone to
     implement (and maybe even impossible with just
     dotlocks to work from, as it requires some
     inter-process communication).

  2. Avoid background runs of commands like "git status"
     that want to do opportunistic updates, preferring
     instead plumbing like diff-files, etc.

     This is awkward for a couple of reasons. One is that
     "status --porcelain" reports a lot more about the
     repository state than is available from individual
     plumbing commands. And two is that we actually _do_
     want to see the refreshed index. We just don't want to
     take a lock or write out the result. Whereas commands
     like diff-files expect us to refresh the index
     separately and write it to disk so that they can depend
     on the result. But that write is exactly what we're
     trying to avoid.

  3. Ask "status" not to lock or write the index.

     This is easy to implement. The big downside is that any
     work done in refreshing the index for such a call is
     lost when the process exits. So a background process
     may end up re-hashing a changed file multiple times
     until the user runs a command that does an index
     refresh themselves.

This patch implements the option 3. The idea (and the test)
is largely stolen from a Git for Windows patch by Johannes
Schindelin, 67e5ce7f63 (status: offer *not* to lock the
index and update it, 2016-08-12). The twist here is that
instead of making this an option to "git status", it becomes
a "git" option and matching environment variable.

The reason there is two-fold:

  1. An environment variable is carried through to
     sub-processes. And whether an invocation is a
     background process or not should apply to the whole
     process tree. So you could do "git --no-optional-locks
     foo", and if "foo" is a script or alias that calls
     "status", you'll still get the effect.

  2. There may be other programs that want the same
     treatment.

     I've punted here on finding more callers to convert,
     since "status" is the obvious one to call as a repeated
     background job. But "git diff"'s opportunistic refresh
     of the index may be a good candidate.

The test is taken from 67e5ce7f63, and it's worth repeating
Johannes's explanation:

  Note that the regression test added in this commit does
  not *really* verify that no index.lock file was written;
  that test is not possible in a portable way. Instead, we
  verify that .git/index is rewritten *only* when `git
  status` is run without `--no-optional-locks`.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-09-27 16:11:01 +09:00
Jeff King
f9b7573f6b repository: free fields before overwriting them
It's possible that the repository data may be initialized
twice (e.g., after doing a chdir() to the top of the
worktree we may have to adjust a relative git_dir path). We
should free() any existing fields before assigning to them
to avoid leaks.

This should be safe, as the fields are set based on the
environment or on other strings like the gitdir or
commondir. That makes it impossible that we are feeding an
alias to the just-freed string.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-09-06 18:06:26 +09:00
Brandon Williams
b415873282 environment: store worktree in the_repository
Migrate 'work_tree' to be stored in 'the_repository'.

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-23 18:24:34 -07:00
Brandon Williams
c14c234f22 environment: place key repository state in the_repository
Migrate 'git_dir', 'git_common_dir', 'git_object_dir', 'git_index_file',
'git_graft_file', and 'namespace' to be stored in 'the_repository'.

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-23 18:24:34 -07:00
Brandon Williams
bf08c8cfc1 environment: remove namespace_len variable
Use 'skip_prefix' instead of 'starts_with' so that we can drop the need
to keep around 'namespace_len'.

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-23 18:24:34 -07:00
Brandon Williams
73f192c991 setup: don't perform lazy initialization of repository state
Under some circumstances (bogus GIT_DIR value or the discovered gitdir
is '.git') 'setup_git_directory()' won't initialize key repository
state.  This leads to inconsistent state after running the setup code.
To account for this inconsistent state, lazy initialization is done once
a caller asks for the repository's gitdir or some other piece of
repository state.  This is confusing and can be error prone.

Instead let's tighten the expected outcome of 'setup_git_directory()'
and ensure that it initializes repository state in all cases that would
have been handled by lazy initialization.

This also lets us drop the requirement to have 'have_git_dir()' check if
the environment variable GIT_DIR was set as that will be handled by the
end of the setup code.

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-23 18:24:34 -07:00
Junio C Hamano
25bf951381 Merge branches 'bw/ls-files-sans-the-index' and 'bw/config-h' into bw/repo-object
* bw/ls-files-sans-the-index:
  ls-files: factor out tag calculation
  ls-files: factor out debug info into a function
  ls-files: convert show_files to take an index
  ls-files: convert show_ce_entry to take an index
  ls-files: convert prune_cache to take an index
  ls-files: convert ce_excluded to take an index
  ls-files: convert show_ru_info to take an index
  ls-files: convert show_other_files to take an index
  ls-files: convert show_killed_files to take an index
  ls-files: convert write_eolinfo to take an index
  ls-files: convert overlay_tree_on_cache to take an index
  tree: convert read_tree to take an index parameter
  convert: convert renormalize_buffer to take an index
  convert: convert convert_to_git to take an index
  convert: convert convert_to_git_filter_fd to take an index
  convert: convert crlf_to_git to take an index
  convert: convert get_cached_convert_stats_ascii to take an index

* bw/config-h:
  config: don't implicitly use gitdir or commondir
  config: respect commondir
  setup: teach discover_git_directory to respect the commondir
  config: don't include config.h by default
  config: remove git_config_iter
  config: create config.h
  alias: use the early config machinery to expand aliases
  t7006: demonstrate a problem with aliases in subdirectories
  t1308: relax the test verifying that empty alias values are disallowed
  help: use early config when autocorrecting aliases
  config: report correct line number upon error
  discover_git_directory(): avoid setting invalid git_dir
2017-06-23 18:24:00 -07:00
Brandon Williams
b2141fc1d2 config: don't include config.h by default
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>
2017-06-15 12:56:22 -07:00
Junio C Hamano
220c6a7080 Merge branch 'jk/bug-to-abort'
Introduce the BUG() macro to improve die("BUG: ...").

* jk/bug-to-abort:
  usage: add NORETURN to BUG() function definitions
  config: complain about --local outside of a git repo
  setup_git_env: convert die("BUG") to BUG()
  usage.c: add BUG() function
2017-05-29 12:34:45 +09:00
Junio C Hamano
4b44b7b1df Merge branch 'nd/worktree-kill-parse-ref'
"git gc" did not interact well with "git worktree"-managed
per-worktree refs.

* nd/worktree-kill-parse-ref:
  refs: kill set_worktree_head_symref()
  worktree.c: kill parse_ref() in favor of refs_resolve_ref_unsafe()
  refs: introduce get_worktree_ref_store()
  refs: add REFS_STORE_ALL_CAPS
  refs.c: make submodule ref store hashmap generic
  environment.c: fix potential segfault by get_git_common_dir()
2017-05-16 11:51:51 +09:00
Jeff King
588a538ae5 setup_git_env: convert die("BUG") to BUG()
Converting to BUG() makes it easier to detect and debug
cases where we hit this assertion. Coupled with a new test
in t1300, this shows that the test suite can detect such
corner cases.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-15 11:30:00 +09:00
Junio C Hamano
cb054eb264 Merge branch 'jk/snprintf-cleanups'
Code clean-up.

* jk/snprintf-cleanups:
  daemon: use an argv_array to exec children
  gc: replace local buffer with git_path
  transport-helper: replace checked snprintf with xsnprintf
  convert unchecked snprintf into xsnprintf
  combine-diff: replace malloc/snprintf with xstrfmt
  replace unchecked snprintf calls with heap buffers
  receive-pack: print --pack-header directly into argv array
  name-rev: replace static buffer with strbuf
  create_branch: use xstrfmt for reflog message
  create_branch: move msg setup closer to point of use
  avoid using mksnpath for refs
  avoid using fixed PATH_MAX buffers for refs
  fetch: use heap buffer to format reflog
  tag: use strbuf to format tag header
  diff: avoid fixed-size buffer for patch-ids
  odb_mkstemp: use git_path_buf
  odb_mkstemp: write filename into strbuf
  do not check odb_mkstemp return value for errors
2017-04-16 23:29:26 -07:00
Nguyễn Thái Ngọc Duy
a560d87033 environment.c: fix potential segfault by get_git_common_dir()
setup_git_env() must be called before this function to initialize
git_common_dir so that it returns a non NULL string. And it must return
a non NULL string or segfault can happen because all callers expect so.

It does not do so explicitly though and depends on get_git_dir() being
called first (which will guarantee setup_git_env()). Avoid this
dependency and call setup_git_env() by itself.

test-ref-store.c will hit this problem because it's very lightweight,
just enough initialization to exercise refs code, and get_git_dir() will
never be called until get_worktrees() is, which uses get_git_common_dir
and hits a segfault.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-16 18:24:29 -07:00
Junio C Hamano
7a09a61e66 Merge branch 'jk/no-looking-at-dotgit-outside-repo-final'
This is the endgame of the topic to avoid blindly falling back to
".git" when the setup sequence said we are _not_ in Git repository.
A corner case that happens to work right now may be broken by a
call to die("BUG").

* jk/no-looking-at-dotgit-outside-repo-final:
  setup_git_env: avoid blind fall-back to ".git"
2017-03-30 14:07:13 -07:00
Jeff King
4aa7d75e48 odb_mkstemp: use git_path_buf
Since git_path_buf() is smart enough to replace "objects/"
with the correct object path, we can use it instead of
manually assembling the path. That's slightly shorter, and
will clean up any non-canonical bits in the path.

Signed-off-by: Jeff King <peff@peff.net>
2017-03-28 15:28:04 -07:00
Jeff King
594fa9998c odb_mkstemp: write filename into strbuf
The odb_mkstemp() function expects the caller to provide a
fixed buffer to write the resulting tempfile name into. But
it creates the template using snprintf without checking the
return value. This means we could silently truncate the
filename.

In practice, it's unlikely that the truncation would end in
the template-pattern that mkstemp needs to open the file. So
we'd probably end up failing either way, unless the path was
specially crafted.

The simplest fix would be to notice the truncation and die.
However, we can observe that most callers immediately
xstrdup() the result anyway. So instead, let's switch to
using a strbuf, which is easier for them (and isn't a big
deal for the other 2 callers, who can just strbuf_release
when they're done with it).

Note that many of the callers used static buffers, but this
was purely to avoid putting a large buffer on the stack. We
never passed the static buffers out of the function, so
there's no complicated memory handling we need to change.

Signed-off-by: Jeff King <peff@peff.net>
2017-03-28 15:28:04 -07:00
Junio C Hamano
45cbc37c5f Merge branch 'jk/pack-name-cleanups'
Code clean-up.

* jk/pack-name-cleanups:
  index-pack: make pointer-alias fallbacks safer
  replace snprintf with odb_pack_name()
  odb_pack_keep(): stop generating keepfile name
  sha1_file.c: make pack-name helper globally accessible
  move odb_* declarations out of git-compat-util.h
2017-03-21 15:07:17 -07:00
Jeff King
eaeefc3276 odb_pack_keep(): stop generating keepfile name
The odb_pack_keep() function generates the name of a .keep
file and opens it. This has two problems:

  1. It requires a fixed-size buffer to create the filename
     and doesn't notice when the result is truncated.

  2. Of the two callers, one sometimes wants to open a
     filename it already has, which makes things awkward (it
     has to do so manually, and skips the leading-directory
     creation).

Instead, let's have odb_pack_keep() just open the file.
Generating the name isn't hard, and a future patch will
switch callers over to odb_pack_name() anyway.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-03-16 11:17:00 -07:00
Johannes Schindelin
ce83eadd9a real_pathdup(): fix callsites that wanted it to die on error
In 4ac9006f83 (real_path: have callers use real_pathdup and
strbuf_realpath, 2016-12-12), we changed the xstrdup(real_path())
pattern to use real_pathdup() directly.

The problem with this change is that real_path() calls
strbuf_realpath() with die_on_error = 1 while real_pathdup() calls
it with die_on_error = 0. Meaning that in cases where real_path()
causes Git to die() with an error message, real_pathdup() is silent
and returns NULL instead.

The callers, however, are ill-prepared for that change, as they expect
the return value to be non-NULL (and otherwise the function died
with an appropriate error message).

Fix this by extending real_pathdup()'s signature to accept the
die_on_error flag and simply pass it through to strbuf_realpath(),
and then adjust all callers after a careful audit whether they would
handle NULLs well.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-03-08 14:38:41 -08:00
Cornelius Weig
341fb28621 refs: add option core.logAllRefUpdates = always
When core.logallrefupdates is true, we only create a new reflog for refs
that are under certain well-known hierarchies. The reason is that we
know that some hierarchies (like refs/tags) are not meant to change, and
that unknown hierarchies might not want reflogs at all (e.g., a
hypothetical refs/foo might be meant to change often and drop old
history immediately).

However, sometimes it is useful to override this decision and simply log
for all refs, because the safety and audit trail is more important than
the performance implications of keeping the log around.

This patch introduces a new "always" mode for the core.logallrefupdates
option which will log updates to everything under refs/, regardless
where in the hierarchy it is (we still will not log things like
ORIG_HEAD and FETCH_HEAD, which are known to be transient).

Based-on-patch-by: Jeff King <peff@peff.net>
Signed-off-by: Cornelius Weig <cornelius.weig@tngtech.com>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-01-31 10:01:24 -08:00
Junio C Hamano
55d128ae06 Merge branch 'bw/grep-recurse-submodules'
"git grep" has been taught to optionally recurse into submodules.

* bw/grep-recurse-submodules:
  grep: search history of moved submodules
  grep: enable recurse-submodules to work on <tree> objects
  grep: optionally recurse into submodules
  grep: add submodules as a grep source type
  submodules: load gitmodules file from commit sha1
  submodules: add helper to determine if a submodule is initialized
  submodules: add helper to determine if a submodule is populated
  real_path: canonicalize directory separators in root parts
  real_path: have callers use real_pathdup and strbuf_realpath
  real_path: create real_pathdup
  real_path: convert real_path_internal to strbuf_realpath
  real_path: resolve symlinks by hand
2017-01-18 15:12:11 -08:00
Brandon Williams
4ac9006f83 real_path: have callers use real_pathdup and strbuf_realpath
Migrate callers of real_path() who duplicate the retern value to use
real_pathdup or strbuf_realpath.

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-12-12 15:22:32 -08:00
Junio C Hamano
8de7eeb54b compression: unify pack.compression configuration parsing
There are three codepaths that use a variable whose name is
pack_compression_level to affect how objects and deltas sent to a
packfile is compressed.  Unlike zlib_compression_level that controls
the loose object compression, however, this variable was static to
each of these codepaths.  Two of them read the pack.compression
configuration variable, using core.compression as the default, and
one of them also allowed overriding it from the command line.

The other codepath in bulk-checkin did not pay any attention to the
configuration.

Unify the configuration parsing to git_default_config(), where we
implement the parsing of core.loosecompression and core.compression
and make the former override the latter, by moving code to parse
pack.compression and also allow core.compression to give default to
this variable.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-11-15 21:16:22 -08:00
Junio C Hamano
580d820ece Merge branch 'lt/abbrev-auto'
Allow the default abbreviation length, which has historically been
7, to scale as the repository grows.  The logic suggests to use 12
hexdigits for the Linux kernel, and 9 to 10 for Git itself.

* lt/abbrev-auto:
  abbrev: auto size the default abbreviation
  abbrev: prepare for new world order
  abbrev: add FALLBACK_DEFAULT_ABBREV to prepare for auto sizing
2016-10-27 14:58:47 -07:00
Jeff King
b1ef400eec setup_git_env: avoid blind fall-back to ".git"
When we default to ".git" without having done any kind of
repository setup, the results quite often do what the user
expects.  But this has also historically been the cause of
some poorly behaved corner cases. These cases can be hard to
find, because they happen at the conjunction of two
relatively rare circumstances:

  1. We are running some code which assumes there's a
     repository present, but there isn't necessarily one
     (e.g., low-level diff code triggered by "git diff
     --no-index" might try to look at some repository data).

  2. We have an unusual setup, like being in a subdirectory
     of the working tree, or we have a .git file (rather
     than a directory), or we are running a tool like "init"
     or "clone" which may operate on a repository in a
     different directory.

Our test scripts often cover (1), but miss doing (2) at the
same time, and so the fallback appears to work but has
lurking bugs. We can flush these bugs out by refusing to do
the fallback entirely., This makes potential problems a lot
more obvious by complaining even for "usual" setups.

This passes the test suite (after the adjustments in the
previous patches), but there's a risk of regression for any
cases where the fallback usually works fine but the code
isn't exercised by the test suite.  So by itself, this
commit is a potential step backward, but lets us take two
steps forward once we've identified and fixed any such
instances.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-10-26 13:30:51 -07:00
Junio C Hamano
1c2b1f7018 Merge branch 'bw/ls-files-recurse-submodules'
"git ls-files" learned "--recurse-submodules" option that can be
used to get a listing of tracked files across submodules (i.e. this
only works with "--cached" option, not for listing untracked or
ignored files).  This would be a useful tool to sit on the upstream
side of a pipe that is read with xargs to work on all working tree
files from the top-level superproject.

* bw/ls-files-recurse-submodules:
  ls-files: add pathspec matching for submodules
  ls-files: pass through safe options for --recurse-submodules
  ls-files: optionally recurse into submodules
  git: make super-prefix option
2016-10-26 13:14:44 -07:00
Brandon Williams
74866d7579 git: make super-prefix option
Add a super-prefix environment variable 'GIT_INTERNAL_SUPER_PREFIX'
which can be used to specify a path from above a repository down to its
root.  When such a super-prefix is specified, the paths reported by Git
are prefixed with it to make them relative to that directory "above".
The paths given by the user on the command line
(e.g. "git subcmd --output-file=path/to/a/file" and pathspecs) are taken
relative to the directory "above" to match.

The immediate use of this option is by commands which have a
--recurse-submodule option in order to give context to submodules about
how they were invoked.  This option is currently only allowed for
builtins which support a super-prefix.

Signed-off-by: Brandon Williams <bmwill@google.com>
Reviewed-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-10-10 12:14:58 -07:00
Linus Torvalds
e6c587c733 abbrev: auto size the default abbreviation
In fairly early days we somehow decided to abbreviate object names
down to 7-hexdigits, but as projects grow, it is becoming more and
more likely to see such a short object names made in earlier days
and recorded in the log messages no longer unique.

Currently the Linux kernel project needs 11 to 12 hexdigits, while
Git itself needs 10 hexdigits to uniquely identify the objects they
have, while many smaller projects may still be fine with the
original 7-hexdigit default.  One-size does not fit all projects.

Introduce a mechanism, where we estimate the number of objects in
the repository upon the first request to abbreviate an object name
with the default setting and come up with a sane default for the
repository.  Based on the expectation that we would see collision in
a repository with 2^(2N) objects when using object names shortened
to first N bits, use sufficient number of hexdigits to cover the
number of objects in the repository.  Each hexdigit (4-bits) we add
to the shortened name allows us to have four times (2-bits) as many
objects in the repository.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-10-03 12:54:29 -07:00
Junio C Hamano
65acfeacaa abbrev: add FALLBACK_DEFAULT_ABBREV to prepare for auto sizing
We'll be introducing a new way to decide the default abbreviation
length by initialising DEFAULT_ABBREV to -1 to signal the first call
to "find unique abbreviation" codepath to compute a reasonable value
based on the number of objects we have to avoid collisions.

We have long relied on DEFAULT_ABBREV being a positive concrete
value that is used as the abbreviation length when no extra
configuration or command line option has overridden it.  Some
codepaths wants to use such a positive concrete default value
even before making their first request to actually trigger the
computation for the auto sized default.

Introduce FALLBACK_DEFAULT_ABBREV and use it to the code that
attempts to align the report from "git fetch".  For now, this
macro is also used to initialize the default_abbrev variable,
but the auto-sizing code will use -1 and then use the value of
FALLBACK_DEFAULT_ABBREV as the starting point of auto-sizing.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-10-03 12:54:21 -07:00
Junio C Hamano
d845d727cb Merge branch 'jk/setup-sequence-update'
There were numerous corner cases in which the configuration files
are read and used or not read at all depending on the directory a
Git command was run, leading to inconsistent behaviour.  The code
to set-up repository access at the beginning of a Git process has
been updated to fix them.

* jk/setup-sequence-update:
  t1007: factor out repeated setup
  init: reset cached config when entering new repo
  init: expand comments explaining config trickery
  config: only read .git/config from configured repos
  test-config: setup git directory
  t1302: use "git -C"
  pager: handle early config
  pager: use callbacks instead of configset
  pager: make pager_program a file-local static
  pager: stop loading git_default_config()
  pager: remove obsolete comment
  diff: always try to set up the repository
  diff: handle --no-index prefixes consistently
  diff: skip implicit no-index check when given --no-index
  patch-id: use RUN_SETUP_GENTLY
  hash-object: always try to set up the git repository
2016-09-21 15:15:24 -07:00
Jeff King
4543926ba8 init: reset cached config when entering new repo
After we copy the templates into place, we re-read the
config in case we copied in a default config file. But since
git_config() is backed by a cache these days, it's possible
that the call will not actually touch the filesystem at all;
we need to tell it that something has changed behind the
scenes.

Note that we also need to reset the shared_repository
config. At first glance, it seems like this should probably
just be folded into git_config_clear(). But unfortunately
that is not quite right. The shared repository value may
come from config, _or_ it may have been set manually. So
only the caller who knows whether or not they set it is the
one who can clear it (and indeed, if you _do_ put it into
git_config_clear(), then many tests fail, as we have to
clear the config cache any time we set a new config
variable).

There are three tests here. The first two actually pass
already, though it's largely luck: they just don't happen to
actually read any config before we enter the new repo.

But the third one does fail without this patch; we look at
core.sharedrepository while creating the directory, but need
to make sure the value from the template config overrides
it.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-13 15:45:45 -07:00
Jeff King
b9605bc4f2 config: only read .git/config from configured repos
When git_config() runs, it looks in the system, user-wide,
and repo-level config files. It gets the latter by calling
git_pathdup(), which in turn calls get_git_dir(). If we
haven't set up the git repository yet, this may simply
return ".git", and we will look at ".git/config".  This
seems like it would be helpful (presumably we haven't set up
the repository yet, so it tries to find it), but it turns
out to be a bad idea for a few reasons:

  - it's not sufficient, and therefore hides bugs in a
    confusing way. Config will be respected if commands are
    run from the top-level of the working tree, but not from
    a subdirectory.

  - it's not always true that we haven't set up the
    repository _yet_; we may not want to do it at all. For
    instance, if you run "git init /some/path" from inside
    another repository, it should not load config from the
    existing repository.

  - there might be a path ".git/config", but it is not the
    actual repository we would find via setup_git_directory().
    This may happen, e.g., if you are storing a git
    repository inside another git repository, but have
    munged one of the files in such a way that the
    inner repository is not valid (e.g., by removing HEAD).

We have at least two bugs of the second type in git-init,
introduced by ae5f677 (lazily load core.sharedrepository,
2016-03-11). It causes init to use git_configset(), which
loads all of the config, including values from the current
repo (if any).  This shows up in two ways:

  1. If we happen to be in an existing repository directory,
     we'll read and respect core.sharedrepository from it,
     even though it should have no bearing on the new
     repository. A new test in t1301 covers this.

  2. Similarly, if we're in an existing repo that sets
     core.logallrefupdates, that will cause init to fail to
     set it in a newly created repository (because it thinks
     that the user's templates already did so). A new test
     in t0001 covers this.

We also need to adjust an existing test in t1302, which
gives another example of why this patch is an improvement.

That test creates an embedded repository with a bogus
core.repositoryformatversion of "99". It wants to make sure
that we actually stop at the bogus repo rather than
continuing upward to find the outer repo. So it checks that
"git config core.repositoryformatversion" returns 99. But
that only works because we blindly read ".git/config", even
though we _know_ we're in a repository whose vintage we do
not understand.

After this patch, we avoid reading config from the unknown
vintage repository at all, which is a safer choice.  But we
need to tweak the test, since core.repositoryformatversion
will not return 99; it will claim that it could not find the
variable at all.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-13 15:45:45 -07:00
Jeff King
c0c08897c4 pager: make pager_program a file-local static
This variable is only ever used by the routines in pager.c,
and other parts of the code should always use those routines
(like git_pager()) to make decisions about which pager to
use. Let's reduce its scope to prevent accidents.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-13 15:45:45 -07:00
Junio C Hamano
e29300d69f Merge branch 'js/windows-dotgit' into maint
On Windows, .git and optionally any files whose name starts with a
dot are now marked as hidden, with a core.hideDotFiles knob to
customize this behaviour.

* js/windows-dotgit:
  mingw: remove unnecessary definition
  mingw: introduce the 'core.hideDotFiles' setting
2016-05-26 13:17:23 -07:00
Junio C Hamano
bfc99b63fe Merge branch 'js/windows-dotgit'
On Windows, .git and optionally any files whose name starts with a
dot are now marked as hidden, with a core.hideDotFiles knob to
customize this behaviour.

* js/windows-dotgit:
  mingw: remove unnecessary definition
  mingw: introduce the 'core.hideDotFiles' setting
2016-05-17 14:38:39 -07:00
Junio C Hamano
6675f501f6 Merge branch 'ab/hooks'
A new configuration variable core.hooksPath allows customizing
where the hook directory is.

* ab/hooks:
  hooks: allow customizing where the hook directory is
  githooks.txt: minor improvements to the grammar & phrasing
  githooks.txt: amend dangerous advice about 'update' hook ACL
  githooks.txt: improve the intro section
2016-05-17 14:38:17 -07:00
Johannes Schindelin
f30afdabbf mingw: introduce the 'core.hideDotFiles' setting
On Unix (and Linux), files and directories whose names start with a dot
are usually not shown by default. This convention is used by Git: the
.git/ directory should be left alone by regular users, and only accessed
through Git itself.

On Windows, no such convention exists. Instead, there is an explicit flag
to mark files or directories as hidden.

In the early days, Git for Windows did not mark the .git/ directory (or
for that matter, any file or directory whose name starts with a dot)
hidden. This lead to quite a bit of confusion, and even loss of data.

Consequently, Git for Windows introduced the core.hideDotFiles setting,
with three possible values: true, false, and dotGitOnly, defaulting to
marking only the .git/ directory as hidden.

The rationale: users do not need to access .git/ directly, and indeed (as
was demonstrated) should not really see that directory, either. However,
not all dot files should be hidden by default, as e.g. Eclipse does not
show them (and the user would therefore be unable to see, say, a
.gitattributes file).

In over five years since the last attempt to bring this patch into core
Git, a slightly buggy version of this patch has served Git for Windows'
users well: no single report indicated problems with the hidden .git/
directory, and the stream of problems caused by the previously non-hidden
.git/ directory simply stopped. The bugs have been fixed during the
process of getting this patch upstream.

Note that there is a funny quirk we have to pay attention to when
creating hidden files: we use Win32's _wopen() function which
transmogrifies its arguments and hands off to Win32's CreateFile()
function. That latter function errors out with ERROR_ACCESS_DENIED (the
equivalent of EACCES) when the equivalent of the O_CREAT flag was passed
and the file attributes (including the hidden flag) do not match an
existing file's. And _wopen() accepts no parameter that would be
transmogrified into said hidden flag. Therefore, we simply try again
without O_CREAT.

A slightly different method is required for our fopen()/freopen()
function as we cannot even *remove* the implicit O_CREAT flag.
Therefore, we briefly mark existing files as unhidden when opening them
via fopen()/freopen().

The ERROR_ACCESS_DENIED error can also be triggered by opening a file
that is marked as a system file (which is unlikely to be tracked in
Git), and by trying to create a file that has *just* been deleted and is
awaiting the last open handles to be released (which would be handled
better by the "Try again?" logic, a story for a different patch series,
though). In both cases, it does not matter much if we try again without
the O_CREAT flag, read: it does not hurt, either.

For details how ERROR_ACCESS_DENIED can be triggered, see
https://msdn.microsoft.com/en-us/library/windows/desktop/aa363858

Original-patch-by: Erik Faye-Lund <kusmabite@gmail.com>
Initial-Test-By: Pat Thoyts <patthoyts@users.sourceforge.net>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-05-11 13:54:53 -07:00
Ævar Arnfjörð Bjarmason
867ad08a26 hooks: allow customizing where the hook directory is
Change the hardcoded lookup for .git/hooks/* to optionally lookup in
$(git config core.hooksPath)/* instead.

This is essentially a more intrusive version of the git-init ability to
specify hooks on init time via init templates.

The difference between that facility and this feature is that this can
be set up after the fact via e.g. ~/.gitconfig or /etc/gitconfig to
apply for all your personal repositories, or all repositories on the
system.

I plan on using this on a centralized Git server where users can create
arbitrary repositories under /gitroot, but I'd like to manage all the
hooks that should be run centrally via a unified dispatch mechanism.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-05-04 16:25:13 -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
907c416534 Merge branch 'jk/check-repository-format'
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()
2016-04-13 14:12:28 -07:00
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
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
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
0e35fcb412 Merge branch 'cc/untracked'
Update the untracked cache subsystem and change its primary UI from
"git update-index" to "git config".

* cc/untracked:
  t7063: add tests for core.untrackedCache
  test-dump-untracked-cache: don't modify the untracked cache
  config: add core.untrackedCache
  dir: simplify untracked cache "ident" field
  dir: add remove_untracked_cache()
  dir: add {new,add}_untracked_cache()
  update-index: move 'uc' var declaration
  update-index: add untracked cache notifications
  update-index: add --test-untracked-cache
  update-index: use enum for untracked cache options
  dir: free untracked cache when removing it
2016-02-10 14:20:06 -08:00