Implement command options `--run` and `--start` 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 wait for connections from
Git clients over a well-known named pipe or Unix domain
socket.
This version does not actually do anything yet because the
backends are still just stubs.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Implement command options `--stop`, `--is-running`, `--query`,
`--query-index`, and `--flush` 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>
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>
The `core.fsmonitor` setting is supposed to be set to a path pointing
to a script or executable that (via the Hook API) queries an fsmonitor
process such as watchman.
We are about to implement our own fsmonitor backend, and do not want
to spawn hook processes just to query it. Let's use `Simple IPC` to
directly communicate with the daemon (and start it if necessary),
guarded by the brand-new `core.useBuiltinFSMonitor` toggle.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
This commit refactors `git_config_get_fsmonitor()` into the `repo_*()`
form that takes a parameter `struct repository *r`.
That change prepares for the upcoming `core.useFSMonitorDaemon` flag which
will be stored in the `repo_settings` struct.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Create client routines to spawn a fsmonitor daemon and send it an IPC
request using `simple-ipc`.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Create a manual page describing the `git fsmonitor--daemon` feature.
Update references to `core.fsmonitor`, `core.fsmonitorHookVersion` and
pointers to `watchman` to mention the built-in FSMonitor.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
My "fsmonitor" feature contains 3 parts. The second part "simple-ipc"
is upstream under review for a while already, and "simple-ipc2" is
intended to enter `next` soon after v2.31.0 has been released. This
merge commit allows my development to continue in parallel.
Create t0052-simple-ipc.sh with unit tests for the "simple-ipc" mechanism.
Create t/helper/test-simple-ipc test tool to exercise the "simple-ipc"
functions.
When the tool is invoked with "run-daemon", it runs a server to listen
for "simple-ipc" connections on a test socket or named pipe and
responds to a set of commands to exercise/stress the communication
setup.
When the tool is invoked with "start-daemon", it spawns a "run-daemon"
command in the background and waits for the server to become ready
before exiting. (This helps make unit tests in t0052 more predictable
and avoids the need for arbitrary sleeps in the test script.)
The tool also has a series of client "send" commands to send commands
and data to a server instance.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Create Unix domain socket based implementation of "simple-ipc".
A set of `ipc_client` routines implement a client library to connect
to an `ipc_server` over a Unix domain socket, send a simple request,
and receive a single response. Clients use blocking IO on the socket.
A set of `ipc_server` routines implement a thread pool to listen for
and concurrently service client connections.
The server creates a new Unix domain socket at a known location. If a
socket already exists with that name, the server tries to determine if
another server is already listening on the socket or if the socket is
dead. If socket is busy, the server exits with an error rather than
stealing the socket. If the socket is dead, the server creates a new
one and starts up.
If while running, the server detects that its socket has been stolen
by another server, it automatically exits.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Create a wrapper class for `unix_stream_listen()` that uses a ".lock"
lockfile to create the unix domain socket in a race-free manner.
Unix domain sockets have a fundamental problem on Unix systems because
they persist in the filesystem until they are deleted. This is
independent of whether a server is actually listening for connections.
Well-behaved servers are expected to delete the socket when they
shutdown. A new server cannot easily tell if a found socket is
attached to an active server or is leftover cruft from a dead server.
The traditional solution used by `unix_stream_listen()` is to force
delete the socket pathname and then create a new socket. This solves
the latter (cruft) problem, but in the case of the former, it orphans
the existing server (by stealing the pathname associated with the
socket it is listening on).
We cannot directly use a .lock lockfile to create the socket because
the socket is created by `bind(2)` rather than the `open(2)` mechanism
used by `tempfile.c`.
As an alternative, we hold a plain lockfile ("<path>.lock") as a
mutual exclusion device. Under the lock, we test if an existing
socket ("<path>") is has an active server. If not, we create a new
socket and begin listening. Then we use "rollback" to delete the
lockfile in all cases.
This wrapper code conceptually exists at a higher-level than the core
unix_stream_connect() and unix_stream_listen() routines that it
consumes. It is isolated in a wrapper class for clarity.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Calls to `chdir()` are dangerous in a multi-threaded context. If
`unix_stream_listen()` or `unix_stream_connect()` is given a socket
pathname that is too long to fit in a `sockaddr_un` structure, it will
`chdir()` to the parent directory of the requested socket pathname,
create the socket using a relative pathname, and then `chdir()` back.
This is not thread-safe.
Teach `unix_sockaddr_init()` to not allow calls to `chdir()` when this
flag is set.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Update `unix_stream_listen()` to take an options structure to override
default behaviors. This commit includes the size of the `listen()` backlog.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
The static helper function `unix_stream_socket()` calls `die()`. This
is not appropriate for all callers. Eliminate the wrapper function
and make the callers propagate the error.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Brief design documentation for new IPC mechanism allowing
foreground Git client to talk with an existing daemon process
at a known location using a named pipe or unix domain socket.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Update the calling sequence of `read_packetized_to_strbuf()` to take
an options argument and not assume a fixed set of options. Update the
only existing caller accordingly to explicitly pass the
formerly-assumed flags.
The `read_packetized_to_strbuf()` function calls `packet_read()` with
a fixed set of assumed options (`PACKET_READ_GENTLE_ON_EOF`). This
assumption has been fine for the single existing caller
`apply_multi_file_filter()` in `convert.c`.
In a later commit we would like to add other callers to
`read_packetized_to_strbuf()` that need a different set of options.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Introduce PACKET_READ_GENTLE_ON_READ_ERROR option to help libify the
packet readers.
So far, the (possibly indirect) callers of `get_packet_data()` can ask
that function to return an error instead of `die()`ing upon end-of-file.
However, random read errors will still cause the process to die.
So let's introduce an explicit option to tell the packet reader
machinery to please be nice and only return an error on read errors.
This change prepares pkt-line for use by long-running daemon processes.
Such processes should be able to serve multiple concurrent clients and
and survive random IO errors. If there is an error on one connection,
a daemon should be able to drop that connection and continue serving
existing and future connections.
This ability will be used by a Git-aware "Builtin FSMonitor" feature
in a later patch series.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Remove the `packet_flush_gently()` call in `write_packetized_from_buf() and
`write_packetized_from_fd()` and require the caller to call it if desired.
Rename both functions to `write_packetized_from_*_no_flush()` to prevent
later merge accidents.
`write_packetized_from_buf()` currently only has one caller:
`apply_multi_file_filter()` in `convert.c`. It always wants a flush packet
to be written after writing the payload.
However, we are about to introduce a caller that wants to write many
packets before a final flush packet, so let's make the caller responsible
for emitting the flush packet.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Teach `packet_write_gently()` to write the pkt-line header and the actual
buffer in 2 separate calls to `write_in_full()` and avoid the need for a
static buffer, thread-safe scratch space, or an excessively large stack
buffer.
Change `write_packetized_from_fd()` to allocate a temporary buffer rather
than using a static buffer to avoid similar issues here.
These changes are intended to make it easier to use pkt-line routines in
a multi-threaded context with multiple concurrent writers writing to
different streams.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
My "fsmonitor" feature contains 3 parts. The first part "fsmonitor-prework"
is already upstream in "next". This merge commit allows my development to
continue in parallel.
Isolate and document initialization of `istate->fsmonitor_last_update`.
This field should contain a fsmonitor-specific opaque token, but we
need to initialize it before we can actually talk to a fsmonitor process,
so we create a generic default value.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Reviewed-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Let's measure the time taken to request and receive FSMonitor data
via the hook API and the size of the response.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Reviewed-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Report the number of files in the working directory that were read and
their hashes verified in `refresh_index()`.
FSMonitor improves the performance of commands like `git status` by
avoiding scanning the disk for changed files. Let's measure this.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Reviewed-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Report the total number of calls made to lstat() inside of refresh_index().
FSMonitor improves the performance of commands like `git status` by
avoiding scanning the disk for changed files. This can be seen in
`refresh_index()`. Let's measure this.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Reviewed-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Report the total number of calls made to lstat() inside preload_index().
FSMonitor improves the performance of commands like `git status` by
avoiding scanning the disk for changed files. This can be seen in
`preload_index()`. Let's measure this.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Reviewed-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add optional trace logging to allow us to better compare performance of
various fsmonitor providers and compare results with non-fsmonitor runs.
Currently, this includes Trace2 logging, but may be extended to include
other trace targets, such as GIT_TRACE_FSMONITOR if desired.
Using this logging helped me explain an odd behavior on MacOS where the
kernel was dropping events and causing the hook to Watchman to timeout.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Reviewed-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Shutdown Watchman after the Watchman-based tests and before the block of
"no fsmonitor" tests.
This helps ensure that Watchman cannot affect the test results for the
other.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Reviewed-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Only use the final portion of the test trash directory file name
when verifying that Watchman was started.
On Windows and under the SDK, $GIT_WORKTREE is a cygwin-style
path with forward slashes and a "/c/" drive name. However
`watchman watch-list` reports a proper Windows-style pathname
with drive letters and backslashes. This causes the grep to
fail. Since we don't really care about the full pathname (and
we really don't want to bother with normalizaing them), just see
if the test-name portion of the path is found.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Reviewed-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Convert the test to use a more portable method to update the mtime on a
large number of files under version control.
The Mac version of xargs does not support the "-d" option.
Likewise, the "-0" and "--null" options are not portable.
Furthermore, use `test-tool chmtime` rather than `touch` to update the
mtime to ensure that it is actually updated (especially on file systems
with only whole second resolution).
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Reviewed-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Our setting of GitHub CI test jobs were a bit too eager to give up
once there is even one failure found. Tweak the knob to allow
other jobs keep running even when we see a failure, so that we can
find more failures in a single run.
* pb/ci-matrix-wo-shortcut:
ci: do not cancel all jobs of a matrix if one fails
The implementation of "git branch --sort" wrt the detached HEAD
display has always been hacky, which has been cleaned up.
* ab/branch-sort:
branch: show "HEAD detached" first under reverse sort
branch: sort detached HEAD based on a flag
ref-filter: move ref_sorting flags to a bitfield
ref-filter: move "cmp_fn" assignment into "else if" arm
ref-filter: add braces to if/else if/else chain
branch tests: add to --sort tests
branch: change "--local" to "--list" in comment
Code clean-up.
* ma/t1300-cleanup:
t1300: don't needlessly work with `core.foo` configs
t1300: remove duplicate test for `--file no-such-file`
t1300: remove duplicate test for `--file ../foo`
A 3-year old test that was not testing anything useful has been
corrected.
* fc/t6030-bisect-reset-removes-auxiliary-files:
test: bisect-porcelain: fix location of files
