Commit Graph

31 Commits

Author SHA1 Message Date
Junio C Hamano
6047b28eb7 Merge branch 'en/header-split-cleanup'
Split key function and data structure definitions out of cache.h to
new header files and adjust the users.

* en/header-split-cleanup:
  csum-file.h: remove unnecessary inclusion of cache.h
  write-or-die.h: move declarations for write-or-die.c functions from cache.h
  treewide: remove cache.h inclusion due to setup.h changes
  setup.h: move declarations for setup.c functions from cache.h
  treewide: remove cache.h inclusion due to environment.h changes
  environment.h: move declarations for environment.c functions from cache.h
  treewide: remove unnecessary includes of cache.h
  wrapper.h: move declarations for wrapper.c functions from cache.h
  path.h: move function declarations for path.c functions from cache.h
  cache.h: remove expand_user_path()
  abspath.h: move absolute path functions from cache.h
  environment: move comment_line_char from cache.h
  treewide: remove unnecessary cache.h inclusion from several sources
  treewide: remove unnecessary inclusion of gettext.h
  treewide: be explicit about dependence on gettext.h
  treewide: remove unnecessary cache.h inclusion from a few headers
2023-04-06 13:38:31 -07:00
Jeff King
5247b762d0 builtins: mark unused prefix parameters
All builtins receive a "prefix" parameter, but it is only useful if they
need to adjust filenames given by the user on the command line. For
builtins that do not even call parse_options(), they often don't look at
the prefix at all, and -Wunused-parameter complains.

Let's annotate those to silence the compiler warning. I gave a quick
scan of each of these cases, and it seems like they don't have anything
they _should_ be using the prefix for (i.e., there is no hidden bug that
we are missing). The only questionable cases I saw were:

  - in git-unpack-file, we create a tempfile which will always be at the
    root of the repository, even if the command is run from a subdir.
    Arguably this should be created in the subdir from which we're run
    (as we report the path only as a relative name). However, nobody has
    complained, and I'm hesitant to change something that is deep
    plumbing going back to April 2005 (though I think within our
    scripts, the sole caller in git-merge-one-file would be OK, as it
    moves to the toplevel itself).

  - in fetch-pack, local-filesystem remotes are taken as relative to the
    project root, not the current directory. So:

       git init server.git
       [...put stuff in server.git...]
       git init client.git
       cd client.git
       mkdir subdir
       cd subdir
       git fetch-pack ../../server.git ...

    won't work, as we quietly move to the top of the repository before
    interpreting the path (so "../server.git" would work). This is
    weird, but again, nobody has complained and this is how it has
    always worked. And this is how "git fetch" works, too. Plus it
    raises questions about how a configured remote like:

      git config remote.origin.url ../server.git

    should behave. I can certainly come up with a reasonable set of
    behavior, but it may not be worth stirring up complications in a
    plumbing tool.

So I've left the behavior untouched in both of those cases. If anybody
really wants to revisit them, it's easy enough to drop the UNUSED
marker. This commit is just about removing them as obstacles to turning
on -Wunused-parameter all the time.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-03-28 14:11:24 -07:00
Elijah Newren
32a8f51061 environment.h: move declarations for environment.c functions from cache.h
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-03-21 10:56:53 -07:00
Elijah Newren
0b027f6ca7 abspath.h: move absolute path functions from cache.h
This is another step towards letting us remove the include of cache.h in
strbuf.c.  It does mean that we also need to add includes of abspath.h
in a number of C files.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-03-21 10:56:52 -07:00
Elijah Newren
f394e093df treewide: be explicit about dependence on gettext.h
Dozens of files made use of gettext functions, without explicitly
including gettext.h.  This made it more difficult to find which files
could remove a dependence on cache.h.  Make C files explicitly include
gettext.h if they are using it.

However, while compat/fsmonitor/fsm-ipc-darwin.c should also gain an
include of gettext.h, it was left out to avoid conflicting with an
in-flight topic.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-03-21 10:56:51 -07:00
Elijah Newren
36bf195890 alloc.h: move ALLOC_GROW() functions from cache.h
This allows us to replace includes of cache.h with includes of the much
smaller alloc.h in many places.  It does mean that we also need to add
includes of alloc.h in a number of C files.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-02-23 17:25:28 -08:00
Junio C Hamano
4e09e0dae6 Merge branch 'sx/pthread-error-check-fix'
Correct pthread API usage.

* sx/pthread-error-check-fix:
  maintenance: compare output of pthread functions for inequality with 0
2022-12-19 11:46:17 +09:00
Junio C Hamano
44265e5b57 Merge branch 'jh/t7527-unflake-by-forcing-cookie'
Make fsmonitor more robust to avoid the flakiness seen in t7527.

* jh/t7527-unflake-by-forcing-cookie:
  fsmonitor: fix race seen in t7527
2022-12-19 11:46:13 +09:00
Seija
786e67611d maintenance: compare output of pthread functions for inequality with 0
The documentation for pthread_create and pthread_sigmask state that:

"On success, pthread_create() returns 0;
on error, it returns an error number"

As such, we ought to check for an error
by seeing if the output is not 0.

Checking for "less than" is a mistake
as the error code numbers can be greater than 0.

Signed-off-by: Seija <doremylover123@gmail.com>
Acked-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-12-05 10:15:54 +09:00
Jeff Hostetler
6692d45477 fsmonitor: fix race seen in t7527
Fix racy tests in t7527 by forcing the use of cookie files during all
types of queries.  There were originaly observed on M1 macs with file
system encryption enabled.

There were a series of simple tests, such as "edit some files" and
"create some files", that started the daemon with GIT_TRACE_FSMONITOR
enabled so that the daemon would emit "event: <path>" messages to the
trace log.  The test would make worktree modifications and then grep
the log file to confirm it contained the expected trace messages.
The greps would occasionally racily-fail.  The expected messages
were always present in the log file, just not yet always present
when the greps ran.

NEEDSWORK: One could argue that the tests should use the `test-tool
fsmonitor-client query` and search for the expected pathnames in the
output rather than grepping the trace log, but I'll leave that for a
later exercise.

The racy tests called `test-tool fsmonitor-client query --token 0`
before grepping the log file.  (Presumably to introduce a small delay
and/or to let the daemon sync with the file system following the last
modification, but that was not always sufficient and hence the race.)

When the query arg is just "0", the daemon treated it as a V1
(aka timestamp-relative request) and responded with a "trivial
response" and a new token, but without trying to catch up to the
the file system event stream.  So the "event: <path>" messages
may or may not yet be in the log file when the grep commands
started.

FWIW, if the tests had sent `--token builtin:0:0` instead, it would
have forced a slightly different code path in the daemon that would
cause the daemon to use a cookie file and let it catch up with the
file system event stream.  I did not see any test failures with this
change.

Instead of modifying the test, I updated the fsmonitor--daemon to
always use a cookie file and catch up to the file system on any
query operation, regardless of the format of the request token.
This is safer.

FWIW, I think the effect of the race was limited to the test.
Commands like `git status` would always do a full scan when getting a
trivial response.  The fact that the daemon was slighly behind the
file system when it generated the response token would cause a second
`git status` to get a few extra paths that the client would have to
examine, but it would not be missing paths.

FWIW, I also think that an earlier version of the code always did
the cookie file for all types of queries, but it was optimized out
during a round of reviews or rework and we didn't notice the race.

Signed-off-by: Jeff Hostetler <jeffhostetler@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-12-02 09:07:48 +09:00
Junio C Hamano
1655ac884a Merge branch 'ah/fsmonitor-daemon-usage-non-l10n' into maint-2.38
Fix messages incorrectly marked for translation.

* ah/fsmonitor-daemon-usage-non-l10n:
  fsmonitor--daemon: don't translate literal commands
2022-10-25 17:11:33 -07:00
Junio C Hamano
7b8cfe34d9 Merge branch 'ed/fsmonitor-on-networked-macos'
By default, use of fsmonitor on a repository on networked
filesystem is disabled. Add knobs to make it workable on macOS.

* ed/fsmonitor-on-networked-macos:
  fsmonitor: fix leak of warning message
  fsmonitor: add documentation for allowRemote and socketDir options
  fsmonitor: check for compatability before communicating with fsmonitor
  fsmonitor: deal with synthetic firmlinks on macOS
  fsmonitor: avoid socket location check if using hook
  fsmonitor: relocate socket file if .git directory is remote
  fsmonitor: refactor filesystem checks to common interface
2022-10-17 14:56:31 -07:00
Junio C Hamano
ab26e44d98 Merge branch 'ah/fsmonitor-daemon-usage-non-l10n'
Fix messages incorrectly marked for translation.

* ah/fsmonitor-daemon-usage-non-l10n:
  fsmonitor--daemon: don't translate literal commands
2022-10-10 10:08:39 -07:00
Eric DeCosta
12fd27df79 fsmonitor: deal with synthetic firmlinks on macOS
Starting with macOS 10.15 (Catalina), Apple introduced a new feature
called 'firmlinks' in order to separate the boot volume into two
volumes, one read-only and one writable but still present them to the
user as a single volume. Along with this change, Apple removed the
ability to create symlinks in the root directory and replaced them with
'synthetic firmlinks'. See 'man synthetic.conf'

When FSEevents reports the path of changed files, if the path involves
a synthetic firmlink, the path is reported from the point of the
synthetic firmlink and not the real path. For example:

Real path:
/System/Volumes/Data/network/working/directory/foo.txt

Synthetic firmlink:
/network -> /System/Volumes/Data/network

FSEvents path:
/network/working/directory/foo.txt

This causes the FSEvents path to not match against the worktree
directory.

There are several ways in which synthetic firmlinks can be created:
they can be defined in /etc/synthetic.conf, the automounter can create
them, and there may be other means. Simply reading /etc/synthetic.conf
is insufficient. No matter what process creates synthetic firmlinks,
they all get created in the root directory.

Therefore, in order to deal with synthetic firmlinks, the root directory
is scanned and the first possible synthetic firmink that, when resolved,
is a prefix of the worktree is used to map FSEvents paths to worktree
paths.

Signed-off-by: Eric DeCosta <edecosta@mathworks.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-10-05 11:05:23 -07:00
Eric DeCosta
6beb2688d3 fsmonitor: relocate socket file if .git directory is remote
If the .git directory is on a remote filesystem, create the socket
file in 'fsmonitor.socketDir' if it is defined, else create it in $HOME.

Signed-off-by: Eric DeCosta <edecosta@mathworks.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-10-05 11:05:22 -07:00
Alex Henrie
02cb8b9ee3 fsmonitor--daemon: don't translate literal commands
These commands have no placeholders to be translated.

Signed-off-by: Alex Henrie <alexhenrie24@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-09-21 11:56:42 -07:00
Jeff Hostetler
d06055501b fsmonitor--daemon: stub in health thread
Create another thread to watch over the daemon process and
automatically shut it down if necessary.

This commit creates the basic framework for a "health" thread
to monitor the daemon and/or the file system.  Later commits
will add platform-specific code to do the actual work.

The "health" thread is intended to monitor conditions that
would be difficult to track inside the IPC thread pool and/or
the file system listener threads.  For example, when there are
file system events outside of the watched worktree root or if
we want to have an idle-timeout auto-shutdown feature.

This commit creates the health thread itself, defines the thread-proc
and sets up the thread's event loop.  It integrates this new thread
into the existing IPC and Listener thread models.

This commit defines the API to the platform-specific code where all of
the monitoring will actually happen.

The platform-specific code for MacOS is just stubs.  Meaning that the
health thread will immediately exit on MacOS, but that is OK and
expected.  Future work can define MacOS-specific monitoring.

The platform-specific code for Windows sets up enough of the
WaitForMultipleObjects() machinery to watch for system and/or custom
events.  Currently, the set of wait handles only includes our custom
shutdown event (sent from our other theads).  Later commits in this
series will extend the set of wait handles to monitor other
conditions.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-26 15:59:27 -07:00
Jeff Hostetler
207534e423 fsmonitor--daemon: rename listener thread related variables
Rename platform-specific listener thread related variables
and data types as we prepare to add another backend thread
type.

[] `struct fsmonitor_daemon_backend_data` becomes `struct fsm_listen_data`
[] `state->backend_data` becomes `state->listen_data`
[] `state->error_code` becomes `state->listen_error_code`

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-26 15:59:26 -07:00
Jeff Hostetler
802aa31840 fsmonitor--daemon: prepare for adding health thread
Refactor daemon thread startup to make it easier to start
a third thread class to monitor the health of the daemon.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-26 15:59:26 -07:00
Jeff Hostetler
39664e9309 fsmonitor--daemon: cd out of worktree root
Teach the fsmonitor--daemon to CD outside of the worktree
before starting up.

The common Git startup mechanism causes the CWD of the daemon process
to be in the root of the worktree.  On Windows, this causes the daemon
process to hold a locked handle on the CWD and prevents other
processes from moving or deleting the worktree while the daemon is
running.

CD to HOME before entering main event loops.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-26 15:59:26 -07:00
Jeff Hostetler
62a62a2830 fsmonitor-settings: bare repos are incompatible with FSMonitor
Bare repos do not have a worktree, so there is nothing for the
daemon watch.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-26 15:59:26 -07:00
Jeff Hostetler
b05880d357 fsmonitor--daemon: use a cookie file to sync with file system
Teach fsmonitor--daemon client threads to create a cookie file
inside the .git directory and then wait until FS events for the
cookie are observed by the FS listener thread.

This helps address the racy nature of file system events by
blocking the client response until the kernel has drained any
event backlog.

This is especially important on MacOS where kernel events are
only issued with a limited frequency.  See the `latency` argument
of `FSeventStreamCreate()`.  The kernel only signals every `latency`
seconds, but does not guarantee that the kernel queue is completely
drained, so we may have to wait more than one interval.  If we
increase the latency, the system is more likely to drop events.
We avoid these issues by having each client thread create a unique
cookie file and then wait until it is seen in the event stream.

Co-authored-by: Kevin Willford <Kevin.Willford@microsoft.com>
Co-authored-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-03-25 16:04:17 -07:00
Jeff Hostetler
50c725d6b6 fsmonitor--daemon: periodically truncate list of modified files
Teach fsmonitor--daemon to periodically truncate the list of
modified files to save some memory.

Clients will ask for the set of changes relative to a token that they
found in the FSMN index extension in the index.  (This token is like a
point in time, but different).  Clients will then update the index to
contain the response token (so that subsequent commands will be
relative to this new token).

Therefore, the daemon can gradually truncate the in-memory list of
changed paths as they become obsolete (older than the previous token).
Since we may have multiple clients making concurrent requests with a
skew of tokens and clients may be racing to the talk to the daemon,
we lazily truncate the list.

We introduce a 5 minute delay and truncate batches 5 minutes after
they are considered obsolete.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-03-25 16:04:17 -07:00
Jeff Hostetler
518a522f40 fsmonitor--daemon: implement handle_client callback
Teach fsmonitor--daemon to respond to IPC requests from client
Git processes and respond with a list of modified pathnames
relative to the provided token.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-03-25 16:04:16 -07:00
Jeff Hostetler
bec486b9c1 fsmonitor--daemon: create token-based changed path cache
Teach fsmonitor--daemon to build a list of changed paths and associate
them with a token-id.  This will be used by the platform-specific
backends to accumulate changed paths in response to filesystem events.

The platform-specific file system listener thread receives file system
events containing one or more changed pathnames (with whatever
bucketing or grouping that is convenient for the file system).  These
paths are accumulated (without locking) by the file system layer into
a `fsmonitor_batch`.

When the file system layer has drained the kernel event queue, it will
"publish" them to our token queue and make them visible to concurrent
client worker threads.  The token layer is free to combine and/or de-dup
paths within these batches for efficient presentation to clients.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-03-25 16:04:16 -07:00
Jeff Hostetler
aeef767a41 fsmonitor--daemon: define token-ids
Teach fsmonitor--daemon to create token-ids and define the
overall token naming scheme.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-03-25 16:04:16 -07:00
Jeff Hostetler
0ae7a1d9ab fsmonitor--daemon: add pathname classification
Teach fsmonitor--daemon to classify relative and absolute
pathnames and decide how they should be handled.  This will
be used by the platform-specific backend to respond to each
filesystem event.

When we register for filesystem notifications on a directory,
we get events for everything (recursively) in the directory.
We want to report to clients changes to tracked and untracked
paths within the working directory proper.  We do not want to
report changes within the .git directory, for example.

This classification will be used in a later commit by the
different backends to classify paths as events are received.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-03-25 16:04:16 -07:00
Jeff Hostetler
c284e27ba7 fsmonitor--daemon: implement 'start' command
Implement 'git fsmonitor--daemon start' command.  This command starts
an instance of 'git fsmonitor--daemon run' in the background using
the new 'start_bg_command()' function.

We avoid the fork-and-call technique on Unix systems in favor of a
fork-and-exec technique.  This gives us more uniform Trace2 child-*
events.  It also makes our usage more consistent with Windows usage.

On Windows, teach 'git fsmonitor--daemon run' to optionally call
'FreeConsole()' to release handles to the inherited Win32 console
(despite being passed invalid handles for stdin/out/err).  Without
this, command prompts and powershell terminal windows could hang
in "exit" until the last background child process exited or released
their Win32 console handle.  (This was not seen with git-bash shells
because they don't have a Win32 console attached to them.)

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-03-25 16:04:15 -07:00
Jeff Hostetler
9dcba0ba08 fsmonitor--daemon: implement 'run' command
Implement `run` command to try to begin listening for file system events.

This version defines the thread structure with a single fsmonitor_fs_listen
thread to watch for file system events and a simple IPC thread pool to
watch for connection from Git clients over a well-known named pipe or
Unix domain socket.

This commit does not actually do anything yet because the platform
backends are still just stubs.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-03-25 16:04:15 -07:00
Jeff Hostetler
abc9dbc0c1 fsmonitor--daemon: implement 'stop' and 'status' commands
Implement `stop` and `status` client commands to control and query the
status of a `fsmonitor--daemon` server process (and implicitly start a
server process if necessary).

Later commits will implement the actual server and monitor the file
system.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-03-25 16:04:15 -07:00
Jeff Hostetler
16d9d6175b fsmonitor--daemon: add a built-in fsmonitor daemon
Create a built-in file system monitoring daemon that can be used by
the existing `fsmonitor` feature (protocol API and index extension)
to improve the performance of various Git commands, such as `status`.

The `fsmonitor--daemon` feature builds upon the `Simple IPC` API and
provides an alternative to hook access to existing fsmonitors such
as `watchman`.

This commit merely adds the new command without any functionality.

Co-authored-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-03-25 16:04:15 -07:00