From 39418741bd0ab5054cbf4607b8475e5e00d395cd Mon Sep 17 00:00:00 2001 From: Jeff Hostetler Date: Mon, 14 Dec 2020 13:48:26 -0500 Subject: [PATCH 01/25] fsmonitor--daemon: man page and documentation 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 --- Documentation/config/core.txt | 45 +++++++--- Documentation/git-fsmonitor--daemon.txt | 104 ++++++++++++++++++++++++ Documentation/git-update-index.txt | 4 +- Documentation/githooks.txt | 3 +- 4 files changed, 144 insertions(+), 12 deletions(-) create mode 100644 Documentation/git-fsmonitor--daemon.txt diff --git a/Documentation/config/core.txt b/Documentation/config/core.txt index c04f62a54a154c..d6e2f01966cba3 100644 --- a/Documentation/config/core.txt +++ b/Documentation/config/core.txt @@ -66,18 +66,43 @@ core.fsmonitor:: will identify all files that may have changed since the requested date/time. This information is used to speed up git by avoiding unnecessary processing of files that have not changed. - See the "fsmonitor-watchman" section of linkgit:githooks[5]. ++ +See the "fsmonitor-watchman" section of linkgit:githooks[5]. ++ +Note: FSMonitor hooks (and this config setting) are ignored if the +built-in FSMonitor is enabled (see `core.useBuiltinFSMonitor`). core.fsmonitorHookVersion:: - Sets the version of hook that is to be used when calling fsmonitor. - There are currently versions 1 and 2. When this is not set, - version 2 will be tried first and if it fails then version 1 - will be tried. Version 1 uses a timestamp as input to determine - which files have changes since that time but some monitors - like watchman have race conditions when used with a timestamp. - Version 2 uses an opaque string so that the monitor can return - something that can be used to determine what files have changed - without race conditions. + Sets the version of hook that is to be used when calling the + FSMonitor hook (as configured via `core.fsmonitor`). ++ +There are currently versions 1 and 2. When this is not set, +version 2 will be tried first and if it fails then version 1 +will be tried. Version 1 uses a timestamp as input to determine +which files have changes since that time but some monitors +like watchman have race conditions when used with a timestamp. +Version 2 uses an opaque string so that the monitor can return +something that can be used to determine what files have changed +without race conditions. ++ +Note: FSMonitor hooks (and this config setting) are ignored if the +built-in FSMonitor is enabled (see `core.useBuiltinFSMonitor`). + +core.useBuiltinFSMonitor:: + If set to true, enable the built-in filesystem event watcher (for + technical details, see linkgit:git-fsmonitor--daemon[1]). ++ +Like external (hook-based) FSMonitors, the built-in FSMonitor can speed up +Git commands that need to refresh the Git index (e.g. `git status`) in a +worktree with many files. The built-in FSMonitor facility eliminates the +need to install and maintain an external third-party monitoring tool. ++ +The built-in FSMonitor is currently available only on a limited set of +supported platforms. ++ +Note: if this config setting is set to `true`, any FSMonitor hook +configured via `core.fsmonitor` (and possibly `core.fsmonitorHookVersion`) +is ignored. core.trustctime:: If false, the ctime differences between the index and the diff --git a/Documentation/git-fsmonitor--daemon.txt b/Documentation/git-fsmonitor--daemon.txt new file mode 100644 index 00000000000000..b94f57c97fe472 --- /dev/null +++ b/Documentation/git-fsmonitor--daemon.txt @@ -0,0 +1,104 @@ +git-fsmonitor--daemon(1) +======================== + +NAME +---- +git-fsmonitor--daemon - Builtin file system monitor daemon + +SYNOPSIS +-------- +[verse] +'git fsmonitor--daemon' --start +'git fsmonitor--daemon' --run +'git fsmonitor--daemon' --stop +'git fsmonitor--daemon' --is-running +'git fsmonitor--daemon' --is-supported +'git fsmonitor--daemon' --query +'git fsmonitor--daemon' --query-index +'git fsmonitor--daemon' --flush + +DESCRIPTION +----------- + +Monitors files and directories in the working directory for changes using +platform-specific file system notification facilities. + +It communicates directly with commands like `git status` using the +link:technical/api-simple-ipc.html[simple IPC] interface instead of +the slower linkgit:githooks[5] interface. + +OPTIONS +------- + +--start:: + Starts the fsmonitor daemon in the background. + +--run:: + Runs the fsmonitor daemon in the foreground. + +--stop:: + Stops the fsmonitor daemon running for the current working + directory, if present. + +--is-running:: + Exits with zero status if the fsmonitor daemon is watching the + current working directory. + +--is-supported:: + Exits with zero status if the fsmonitor daemon feature is supported + on this platform. + +--query :: + Connects to the fsmonitor daemon (starting it if necessary) and + requests the list of changed files and directories since the + given token. + This is intended for testing purposes. + +--query-index:: + Read the current `` from the File System Monitor index + extension (if present) and use it to query the fsmonitor daemon. + This is intended for testing purposes. + +--flush:: + Force the fsmonitor daemon to flush its in-memory cache and + re-sync with the file system. + This is intended for testing purposes. + +REMARKS +------- +The fsmonitor daemon is a long running process that will watch a single +working directory. Commands, such as `git status`, should automatically +start it (if necessary) when `core.useBuiltinFSMonitor` is set to `true` +(see linkgit:git-config[1]). + +Configure the built-in FSMonitor via `core.useBuiltinFSMonitor` in each +working directory separately, or globally via `git config --global +core.useBuiltinFSMonitor true`. + +Tokens are opaque strings. They are used by the fsmonitor daemon to +mark a point in time and the associated internal state. Callers should +make no assumptions about the content of the token. In particular, +the should not assume that it is a timestamp. + +Query commands send a request-token to the daemon and it responds with +a summary of the changes that have occurred since that token was +created. The daemon also returns a response-token that the client can +use in a future query. + +For more information see the "File System Monitor" section in +linkgit:git-update-index[1]. + +CAVEATS +------- + +The fsmonitor daemon does not currently know about submodules and does +not know to filter out file system events that happen within a +submodule. If fsmonitor daemon is watching a super repo and a file is +modified within the working directory of a submodule, it will report +the change (as happening against the super repo). However, the client +should properly ignore these extra events, so performance may be affected +but it should not cause an incorrect result. + +GIT +--- +Part of the linkgit:git[1] suite diff --git a/Documentation/git-update-index.txt b/Documentation/git-update-index.txt index 2853f168d97685..8169aad7ee9fcd 100644 --- a/Documentation/git-update-index.txt +++ b/Documentation/git-update-index.txt @@ -498,7 +498,9 @@ FILE SYSTEM MONITOR This feature is intended to speed up git operations for repos that have large working directories. -It enables git to work together with a file system monitor (see the +It enables git to work together with a file system monitor (see +linkgit:git-fsmonitor--daemon[1] +and the "fsmonitor-watchman" section of linkgit:githooks[5]) that can inform it as to what files have been modified. This enables git to avoid having to lstat() every file to find modified files. diff --git a/Documentation/githooks.txt b/Documentation/githooks.txt index b51959ff9418fd..b7d5e926f7b042 100644 --- a/Documentation/githooks.txt +++ b/Documentation/githooks.txt @@ -593,7 +593,8 @@ fsmonitor-watchman This hook is invoked when the configuration option `core.fsmonitor` is set to `.git/hooks/fsmonitor-watchman` or `.git/hooks/fsmonitor-watchmanv2` -depending on the version of the hook to use. +depending on the version of the hook to use, unless overridden via +`core.useBuiltinFSMonitor` (see linkgit:git-config[1]). Version 1 takes two arguments, a version (1) and the time in elapsed nanoseconds since midnight, January 1, 1970. From 2585489f6ed6e1eecb877cadc347bd4da727337f Mon Sep 17 00:00:00 2001 From: Jeff Hostetler Date: Mon, 14 Dec 2020 17:35:32 -0500 Subject: [PATCH 02/25] fsmonitor-ipc: create client routines for git-fsmonitor--daemon Create client routines to spawn a fsmonitor daemon and send it an IPC request using `simple-ipc`. Signed-off-by: Jeff Hostetler --- Makefile | 1 + fsmonitor-ipc.c | 153 ++++++++++++++++++++++++++++++++++++++++++++++++ fsmonitor-ipc.h | 48 +++++++++++++++ help.c | 4 ++ 4 files changed, 206 insertions(+) create mode 100644 fsmonitor-ipc.c create mode 100644 fsmonitor-ipc.h diff --git a/Makefile b/Makefile index c3565fc0f8f7df..209c97aa22df6f 100644 --- a/Makefile +++ b/Makefile @@ -893,6 +893,7 @@ LIB_OBJS += fetch-pack.o LIB_OBJS += fmt-merge-msg.o LIB_OBJS += fsck.o LIB_OBJS += fsmonitor.o +LIB_OBJS += fsmonitor-ipc.o LIB_OBJS += gettext.o LIB_OBJS += gpg-interface.o LIB_OBJS += graph.o diff --git a/fsmonitor-ipc.c b/fsmonitor-ipc.c new file mode 100644 index 00000000000000..b0dc334ff02d43 --- /dev/null +++ b/fsmonitor-ipc.c @@ -0,0 +1,153 @@ +#include "cache.h" +#include "fsmonitor.h" +#include "fsmonitor-ipc.h" +#include "run-command.h" +#include "strbuf.h" +#include "trace2.h" + +#ifdef HAVE_FSMONITOR_DAEMON_BACKEND +#define FSMONITOR_DAEMON_IS_SUPPORTED 1 +#else +#define FSMONITOR_DAEMON_IS_SUPPORTED 0 +#endif + +/* + * A trivial function so that this source file always defines at least + * one symbol even when the feature is not supported. This quiets an + * annoying compiler error. + */ +int fsmonitor_ipc__is_supported(void) +{ + return FSMONITOR_DAEMON_IS_SUPPORTED; +} + +#ifdef HAVE_FSMONITOR_DAEMON_BACKEND + +GIT_PATH_FUNC(fsmonitor_ipc__get_path, "fsmonitor") + +enum ipc_active_state fsmonitor_ipc__get_state(void) +{ + return ipc_get_active_state(fsmonitor_ipc__get_path()); +} + +static int spawn_daemon(void) +{ + const char *args[] = { "fsmonitor--daemon", "--start", NULL }; + + return run_command_v_opt_tr2(args, RUN_COMMAND_NO_STDIN | RUN_GIT_CMD, + "fsmonitor"); +} + +int fsmonitor_ipc__send_query(const char *since_token, + struct strbuf *answer) +{ + int ret = -1; + int tried_to_spawn = 0; + enum ipc_active_state state = IPC_STATE__OTHER_ERROR; + struct ipc_client_connection *connection = NULL; + struct ipc_client_connect_options options + = IPC_CLIENT_CONNECT_OPTIONS_INIT; + + options.wait_if_busy = 1; + options.wait_if_not_found = 0; + + trace2_region_enter("fsm_client", "query", NULL); + + trace2_data_string("fsm_client", NULL, "query/command", + since_token); + +try_again: + state = ipc_client_try_connect(fsmonitor_ipc__get_path(), &options, + &connection); + + switch (state) { + case IPC_STATE__LISTENING: + ret = ipc_client_send_command_to_connection( + connection, since_token, answer); + ipc_client_close_connection(connection); + + trace2_data_intmax("fsm_client", NULL, + "query/response-length", answer->len); + + if (fsmonitor_is_trivial_response(answer)) + trace2_data_intmax("fsm_client", NULL, + "query/trivial-response", 1); + + goto done; + + case IPC_STATE__NOT_LISTENING: + ret = error(_("fsmonitor_ipc__send_query: daemon not available")); + goto done; + + case IPC_STATE__PATH_NOT_FOUND: + if (tried_to_spawn) + goto done; + + tried_to_spawn++; + if (spawn_daemon()) + goto done; + + /* + * Try again, but this time give the daemon a chance to + * actually create the pipe/socket. + * + * Granted, the daemon just started so it can't possibly have + * any FS cached yet, so we'll always get a trivial answer. + * BUT the answer should include a new token that can serve + * as the basis for subsequent requests. + */ + options.wait_if_not_found = 1; + goto try_again; + + case IPC_STATE__INVALID_PATH: + ret = error(_("fsmonitor_ipc__send_query: invalid path '%s'"), + fsmonitor_ipc__get_path()); + goto done; + + case IPC_STATE__OTHER_ERROR: + default: + ret = error(_("fsmonitor_ipc__send_query: unspecified error on '%s'"), + fsmonitor_ipc__get_path()); + goto done; + } + +done: + trace2_region_leave("fsm_client", "query", NULL); + + return ret; +} + +int fsmonitor_ipc__send_command(const char *command, + struct strbuf *answer) +{ + struct ipc_client_connection *connection = NULL; + struct ipc_client_connect_options options + = IPC_CLIENT_CONNECT_OPTIONS_INIT; + int ret; + enum ipc_active_state state; + + strbuf_reset(answer); + + options.wait_if_busy = 1; + options.wait_if_not_found = 0; + + state = ipc_client_try_connect(fsmonitor_ipc__get_path(), &options, + &connection); + if (state != IPC_STATE__LISTENING) { + die("fsmonitor--daemon is not running"); + return -1; + } + + ret = ipc_client_send_command_to_connection(connection, command, answer); + ipc_client_close_connection(connection); + + if (ret == -1) { + die("could not send '%s' command to fsmonitor--daemon", + command); + return -1; + } + + return 0; +} + +#endif diff --git a/fsmonitor-ipc.h b/fsmonitor-ipc.h new file mode 100644 index 00000000000000..7d21c1260151d2 --- /dev/null +++ b/fsmonitor-ipc.h @@ -0,0 +1,48 @@ +#ifndef FSMONITOR_IPC_H +#define FSMONITOR_IPC_H + +/* + * Returns true if a filesystem notification backend is defined + * for this platform. This symbol must always be visible and + * outside of the HAVE_ ifdef. + */ +int fsmonitor_ipc__is_supported(void); + +#ifdef HAVE_FSMONITOR_DAEMON_BACKEND +#include "run-command.h" +#include "simple-ipc.h" + +/* + * Returns the pathname to the IPC named pipe or Unix domain socket + * where a `git-fsmonitor--daemon` process will listen. This is a + * per-worktree value. + */ +const char *fsmonitor_ipc__get_path(void); + +/* + * Try to determine whether there is a `git-fsmonitor--daemon` process + * listening on the IPC pipe/socket. + */ +enum ipc_active_state fsmonitor_ipc__get_state(void); + +/* + * Connect to a `git-fsmonitor--daemon` process via simple-ipc + * and ask for the set of changed files since the given token. + * + * This DOES NOT use the hook interface. + * + * Spawn a daemon process in the background if necessary. + */ +int fsmonitor_ipc__send_query(const char *since_token, + struct strbuf *answer); + +/* + * Connect to a `git-fsmonitor--daemon` process via simple-ipc and + * send a command verb. If no daemon is available, we DO NOT try to + * start one. + */ +int fsmonitor_ipc__send_command(const char *command, + struct strbuf *answer); + +#endif /* HAVE_FSMONITOR_DAEMON_BACKEND */ +#endif /* FSMONITOR_IPC_H */ diff --git a/help.c b/help.c index 3c3bdec21356d9..e22ba1d246a5b0 100644 --- a/help.c +++ b/help.c @@ -11,6 +11,7 @@ #include "version.h" #include "refs.h" #include "parse-options.h" +#include "fsmonitor-ipc.h" struct category_description { uint32_t category; @@ -664,6 +665,9 @@ void get_version_info(struct strbuf *buf, int show_build_options) strbuf_addf(buf, "sizeof-size_t: %d\n", (int)sizeof(size_t)); strbuf_addf(buf, "shell-path: %s\n", SHELL_PATH); /* NEEDSWORK: also save and output GIT-BUILD_OPTIONS? */ + + if (fsmonitor_ipc__is_supported()) + strbuf_addstr(buf, "feature: fsmonitor--daemon\n"); } } From c1dd29e8fa725dc8a719b190f1e219c794f09e67 Mon Sep 17 00:00:00 2001 From: Johannes Schindelin Date: Fri, 5 Mar 2021 21:20:26 +0100 Subject: [PATCH 03/25] config: FSMonitor is repository-specific 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 --- builtin/update-index.c | 4 ++-- config.c | 4 ++-- config.h | 2 +- fsmonitor.c | 2 +- 4 files changed, 6 insertions(+), 6 deletions(-) diff --git a/builtin/update-index.c b/builtin/update-index.c index f1f16f2de526d9..87a1d439a1d470 100644 --- a/builtin/update-index.c +++ b/builtin/update-index.c @@ -1216,14 +1216,14 @@ int cmd_update_index(int argc, const char **argv, const char *prefix) } if (fsmonitor > 0) { - if (git_config_get_fsmonitor() == 0) + if (repo_config_get_fsmonitor(r) == 0) warning(_("core.fsmonitor is unset; " "set it if you really want to " "enable fsmonitor")); add_fsmonitor(&the_index); report(_("fsmonitor enabled")); } else if (!fsmonitor) { - if (git_config_get_fsmonitor() == 1) + if (repo_config_get_fsmonitor(r) == 1) warning(_("core.fsmonitor is set; " "remove it if you really want to " "disable fsmonitor")); diff --git a/config.c b/config.c index f9c400ad3062d9..7bf51a1ff269e1 100644 --- a/config.c +++ b/config.c @@ -2516,9 +2516,9 @@ int git_config_get_max_percent_split_change(void) return -1; /* default value */ } -int git_config_get_fsmonitor(void) +int repo_config_get_fsmonitor(struct repository *r) { - if (git_config_get_pathname("core.fsmonitor", &core_fsmonitor)) + if (repo_config_get_pathname(r, "core.fsmonitor", &core_fsmonitor)) core_fsmonitor = getenv("GIT_TEST_FSMONITOR"); if (core_fsmonitor && !*core_fsmonitor) diff --git a/config.h b/config.h index 9038538ffdcb8d..e14a9d1fe1037d 100644 --- a/config.h +++ b/config.h @@ -609,7 +609,7 @@ int git_config_get_index_threads(int *dest); int git_config_get_untracked_cache(void); int git_config_get_split_index(void); int git_config_get_max_percent_split_change(void); -int git_config_get_fsmonitor(void); +int repo_config_get_fsmonitor(struct repository *r); /* This dies if the configured or default date is in the future */ int git_config_get_expiry(const char *key, const char **output); diff --git a/fsmonitor.c b/fsmonitor.c index ab9bfc60b34e31..9c9b2abc94142d 100644 --- a/fsmonitor.c +++ b/fsmonitor.c @@ -411,7 +411,7 @@ void remove_fsmonitor(struct index_state *istate) void tweak_fsmonitor(struct index_state *istate) { unsigned int i; - int fsmonitor_enabled = git_config_get_fsmonitor(); + int fsmonitor_enabled = repo_config_get_fsmonitor(istate->repo ? istate->repo : the_repository); if (istate->fsmonitor_dirty) { if (fsmonitor_enabled) { From 75226cf5893f1859698c290cdd62e3857e48d4a4 Mon Sep 17 00:00:00 2001 From: Johannes Schindelin Date: Fri, 2 Aug 2019 19:17:25 +0200 Subject: [PATCH 04/25] fsmonitor: introduce `core.useBuiltinFSMonitor` to call the daemon via IPC 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 Signed-off-by: Jeff Hostetler --- config.c | 5 +++++ fsmonitor.c | 20 +++++++++++++++++--- repo-settings.c | 3 +++ repository.h | 2 ++ 4 files changed, 27 insertions(+), 3 deletions(-) diff --git a/config.c b/config.c index 7bf51a1ff269e1..d8649cda05c02a 100644 --- a/config.c +++ b/config.c @@ -2518,6 +2518,11 @@ int git_config_get_max_percent_split_change(void) int repo_config_get_fsmonitor(struct repository *r) { + if (r->settings.use_builtin_fsmonitor > 0) { + core_fsmonitor = "(built-in daemon)"; + return 1; + } + if (repo_config_get_pathname(r, "core.fsmonitor", &core_fsmonitor)) core_fsmonitor = getenv("GIT_TEST_FSMONITOR"); diff --git a/fsmonitor.c b/fsmonitor.c index 9c9b2abc94142d..d7e18fc8cd478c 100644 --- a/fsmonitor.c +++ b/fsmonitor.c @@ -3,6 +3,7 @@ #include "dir.h" #include "ewah/ewok.h" #include "fsmonitor.h" +#include "fsmonitor-ipc.h" #include "run-command.h" #include "strbuf.h" @@ -148,14 +149,27 @@ void write_fsmonitor_extension(struct strbuf *sb, struct index_state *istate) /* * Call the query-fsmonitor hook passing the last update token of the saved results. */ -static int query_fsmonitor(int version, const char *last_update, struct strbuf *query_result) +static int query_fsmonitor(int version, struct index_state *istate, struct strbuf *query_result) { + struct repository *r = istate->repo ? istate->repo : the_repository; + const char *last_update = istate->fsmonitor_last_update; struct child_process cp = CHILD_PROCESS_INIT; int result; if (!core_fsmonitor) return -1; + if (r->settings.use_builtin_fsmonitor > 0) { +#ifdef HAVE_FSMONITOR_DAEMON_BACKEND + return fsmonitor_ipc__send_query(last_update, query_result); +#else + /* Fake a trivial response. */ + warning(_("fsmonitor--daemon unavailable; falling back")); + strbuf_add(query_result, "/", 2); + return 0; +#endif + } + strvec_push(&cp.args, core_fsmonitor); strvec_pushf(&cp.args, "%d", version); strvec_pushf(&cp.args, "%s", last_update); @@ -263,7 +277,7 @@ void refresh_fsmonitor(struct index_state *istate) if (istate->fsmonitor_last_update) { if (hook_version == -1 || hook_version == HOOK_INTERFACE_VERSION2) { query_success = !query_fsmonitor(HOOK_INTERFACE_VERSION2, - istate->fsmonitor_last_update, &query_result); + istate, &query_result); if (query_success) { if (hook_version < 0) @@ -293,7 +307,7 @@ void refresh_fsmonitor(struct index_state *istate) if (hook_version == HOOK_INTERFACE_VERSION1) { query_success = !query_fsmonitor(HOOK_INTERFACE_VERSION1, - istate->fsmonitor_last_update, &query_result); + istate, &query_result); } trace_performance_since(last_update, "fsmonitor process '%s'", core_fsmonitor); diff --git a/repo-settings.c b/repo-settings.c index 0cfe8b787db26d..bbcf71461ba22f 100644 --- a/repo-settings.c +++ b/repo-settings.c @@ -58,6 +58,9 @@ void prepare_repo_settings(struct repository *r) r->settings.core_multi_pack_index = value; UPDATE_DEFAULT_BOOL(r->settings.core_multi_pack_index, 1); + if (!repo_config_get_bool(r, "core.usebuiltinfsmonitor", &value) && value) + r->settings.use_builtin_fsmonitor = 1; + if (!repo_config_get_bool(r, "feature.manyfiles", &value) && value) { UPDATE_DEFAULT_BOOL(r->settings.index_version, 4); UPDATE_DEFAULT_BOOL(r->settings.core_untracked_cache, UNTRACKED_CACHE_WRITE); diff --git a/repository.h b/repository.h index a45f7520fd9e12..a471605037c451 100644 --- a/repository.h +++ b/repository.h @@ -42,6 +42,8 @@ struct repo_settings { int core_multi_pack_index; + int use_builtin_fsmonitor; + unsigned command_requires_full_index:1, sparse_index:1; }; From 81028619b5508ac4161cc4387a4c60878019fa25 Mon Sep 17 00:00:00 2001 From: Jeff Hostetler Date: Wed, 16 Dec 2020 10:24:30 -0500 Subject: [PATCH 05/25] 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 Signed-off-by: Jeff Hostetler --- .gitignore | 1 + Makefile | 1 + builtin.h | 1 + builtin/fsmonitor--daemon.c | 52 +++++++++++++++++++++++++++++++++++++ git.c | 1 + 5 files changed, 56 insertions(+) create mode 100644 builtin/fsmonitor--daemon.c diff --git a/.gitignore b/.gitignore index 311841f9bed577..4baba472aa8261 100644 --- a/.gitignore +++ b/.gitignore @@ -72,6 +72,7 @@ /git-format-patch /git-fsck /git-fsck-objects +/git-fsmonitor--daemon /git-gc /git-get-tar-commit-id /git-grep diff --git a/Makefile b/Makefile index 209c97aa22df6f..8fe1e42a435f59 100644 --- a/Makefile +++ b/Makefile @@ -1097,6 +1097,7 @@ BUILTIN_OBJS += builtin/fmt-merge-msg.o BUILTIN_OBJS += builtin/for-each-ref.o BUILTIN_OBJS += builtin/for-each-repo.o BUILTIN_OBJS += builtin/fsck.o +BUILTIN_OBJS += builtin/fsmonitor--daemon.o BUILTIN_OBJS += builtin/gc.o BUILTIN_OBJS += builtin/get-tar-commit-id.o BUILTIN_OBJS += builtin/grep.o diff --git a/builtin.h b/builtin.h index 16ecd5586f0bee..2470d1cd3a267a 100644 --- a/builtin.h +++ b/builtin.h @@ -159,6 +159,7 @@ int cmd_for_each_ref(int argc, const char **argv, const char *prefix); int cmd_for_each_repo(int argc, const char **argv, const char *prefix); int cmd_format_patch(int argc, const char **argv, const char *prefix); int cmd_fsck(int argc, const char **argv, const char *prefix); +int cmd_fsmonitor__daemon(int argc, const char **argv, const char *prefix); int cmd_gc(int argc, const char **argv, const char *prefix); int cmd_get_tar_commit_id(int argc, const char **argv, const char *prefix); int cmd_grep(int argc, const char **argv, const char *prefix); diff --git a/builtin/fsmonitor--daemon.c b/builtin/fsmonitor--daemon.c new file mode 100644 index 00000000000000..6700bac92c7d97 --- /dev/null +++ b/builtin/fsmonitor--daemon.c @@ -0,0 +1,52 @@ +#include "builtin.h" +#include "config.h" +#include "parse-options.h" +#include "fsmonitor.h" +#include "fsmonitor-ipc.h" +#include "simple-ipc.h" +#include "khash.h" + +static const char * const builtin_fsmonitor__daemon_usage[] = { + NULL +}; + +#ifdef HAVE_FSMONITOR_DAEMON_BACKEND + +int cmd_fsmonitor__daemon(int argc, const char **argv, const char *prefix) +{ + enum daemon_mode { + UNDEFINED_MODE, + } mode = UNDEFINED_MODE; + + struct option options[] = { + OPT_END() + }; + + if (argc == 2 && !strcmp(argv[1], "-h")) + usage_with_options(builtin_fsmonitor__daemon_usage, options); + + git_config(git_default_config, NULL); + + argc = parse_options(argc, argv, prefix, options, + builtin_fsmonitor__daemon_usage, 0); + + switch (mode) { + case UNDEFINED_MODE: + default: + die(_("Unhandled command mode %d"), mode); + } +} + +#else +int cmd_fsmonitor__daemon(int argc, const char **argv, const char *prefix) +{ + struct option options[] = { + OPT_END() + }; + + if (argc == 2 && !strcmp(argv[1], "-h")) + usage_with_options(builtin_fsmonitor__daemon_usage, options); + + die(_("fsmonitor--daemon not supported on this platform")); +} +#endif diff --git a/git.c b/git.c index 18bed9a99647aa..c6160f4a88612c 100644 --- a/git.c +++ b/git.c @@ -533,6 +533,7 @@ static struct cmd_struct commands[] = { { "format-patch", cmd_format_patch, RUN_SETUP }, { "fsck", cmd_fsck, RUN_SETUP }, { "fsck-objects", cmd_fsck, RUN_SETUP }, + { "fsmonitor--daemon", cmd_fsmonitor__daemon, RUN_SETUP }, { "gc", cmd_gc, RUN_SETUP }, { "get-tar-commit-id", cmd_get_tar_commit_id, NO_PARSEOPT }, { "grep", cmd_grep, RUN_SETUP_GENTLY }, From 1b231b5bca6a191c32064ec629d4872deabea4a4 Mon Sep 17 00:00:00 2001 From: Jeff Hostetler Date: Wed, 16 Dec 2020 11:02:46 -0500 Subject: [PATCH 06/25] fsmonitor--daemon: implement client command options 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 --- builtin/fsmonitor--daemon.c | 144 ++++++++++++++++++++++++++++++++++++ 1 file changed, 144 insertions(+) diff --git a/builtin/fsmonitor--daemon.c b/builtin/fsmonitor--daemon.c index 6700bac92c7d97..10434bce4b646e 100644 --- a/builtin/fsmonitor--daemon.c +++ b/builtin/fsmonitor--daemon.c @@ -7,18 +7,144 @@ #include "khash.h" static const char * const builtin_fsmonitor__daemon_usage[] = { + N_("git fsmonitor--daemon --stop"), + N_("git fsmonitor--daemon --is-running"), + N_("git fsmonitor--daemon --query "), + N_("git fsmonitor--daemon --query-index"), + N_("git fsmonitor--daemon --flush"), NULL }; #ifdef HAVE_FSMONITOR_DAEMON_BACKEND +/* + * Acting as a CLIENT. + * + * Send an IPC query to a `git-fsmonitor--daemon` SERVER process and + * ask for the changes since the given token. This will implicitly + * start a daemon process if necessary. The daemon process will + * persist after we exit. + * + * This feature is primarily used by the test suite. + */ +static int do_as_client__query_token(const char *token) +{ + struct strbuf answer = STRBUF_INIT; + int ret; + + ret = fsmonitor_ipc__send_query(token, &answer); + if (ret < 0) + die(_("could not query fsmonitor--daemon")); + + write_in_full(1, answer.buf, answer.len); + strbuf_release(&answer); + + return 0; +} + +/* + * Acting as a CLIENT. + * + * Read the `.git/index` to get the last token written to the FSMonitor index + * extension and use that to make a query. + * + * This feature is primarily used by the test suite. + */ +static int do_as_client__query_from_index(void) +{ + struct index_state *istate = the_repository->index; + + setup_git_directory(); + if (do_read_index(istate, the_repository->index_file, 0) < 0) + die("unable to read index file"); + if (!istate->fsmonitor_last_update) + die("index file does not have fsmonitor extension"); + + return do_as_client__query_token(istate->fsmonitor_last_update); +} + +/* + * Acting as a CLIENT. + * + * Send a "quit" command to the `git-fsmonitor--daemon` (if running) + * and wait for it to shutdown. + */ +static int do_as_client__send_stop(void) +{ + struct strbuf answer = STRBUF_INIT; + int ret; + + ret = fsmonitor_ipc__send_command("quit", &answer); + + /* The quit command does not return any response data. */ + strbuf_release(&answer); + + if (ret) + return ret; + + trace2_region_enter("fsm_client", "polling-for-daemon-exit", NULL); + while (fsmonitor_ipc__get_state() == IPC_STATE__LISTENING) + sleep_millisec(50); + trace2_region_leave("fsm_client", "polling-for-daemon-exit", NULL); + + return 0; +} + +/* + * Acting as a CLIENT. + * + * Send a "flush" command to the `git-fsmonitor--daemon` (if running) + * and tell it to flush its cache. + * + * This feature is primarily used by the test suite to simulate a loss of + * sync with the filesystem where we miss kernel events. + */ +static int do_as_client__send_flush(void) +{ + struct strbuf answer = STRBUF_INIT; + int ret; + + ret = fsmonitor_ipc__send_command("flush", &answer); + if (ret) + return ret; + + write_in_full(1, answer.buf, answer.len); + strbuf_release(&answer); + + return 0; +} + +static int is_ipc_daemon_listening(void) +{ + return fsmonitor_ipc__get_state() == IPC_STATE__LISTENING; +} int cmd_fsmonitor__daemon(int argc, const char **argv, const char *prefix) { enum daemon_mode { UNDEFINED_MODE, + STOP, + IS_RUNNING, + QUERY, + QUERY_INDEX, + FLUSH, } mode = UNDEFINED_MODE; struct option options[] = { + OPT_CMDMODE(0, "stop", &mode, N_("stop the running daemon"), + STOP), + + OPT_CMDMODE(0, "is-running", &mode, + N_("test whether the daemon is running"), + IS_RUNNING), + + OPT_CMDMODE(0, "query", &mode, + N_("query the daemon (starting if necessary)"), + QUERY), + OPT_CMDMODE(0, "query-index", &mode, + N_("query the daemon (starting if necessary) using token from index"), + QUERY_INDEX), + OPT_CMDMODE(0, "flush", &mode, N_("flush cached filesystem events"), + FLUSH), OPT_END() }; @@ -31,6 +157,24 @@ int cmd_fsmonitor__daemon(int argc, const char **argv, const char *prefix) builtin_fsmonitor__daemon_usage, 0); switch (mode) { + case STOP: + return !!do_as_client__send_stop(); + + case IS_RUNNING: + return !is_ipc_daemon_listening(); + + case QUERY: + if (argc != 1) + usage_with_options(builtin_fsmonitor__daemon_usage, + options); + return !!do_as_client__query_token(argv[0]); + + case QUERY_INDEX: + return !!do_as_client__query_from_index(); + + case FLUSH: + return !!do_as_client__send_flush(); + case UNDEFINED_MODE: default: die(_("Unhandled command mode %d"), mode); From bfd2273f687a39415268351f969c82f4b1caec3d Mon Sep 17 00:00:00 2001 From: Jeff Hostetler Date: Thu, 17 Dec 2020 10:29:17 -0500 Subject: [PATCH 07/25] fsmonitor-fs-listen-win32: stub in backend for Windows Stub in empty backend for fsmonitor--daemon on Windows. Signed-off-by: Jeff Hostetler --- Makefile | 13 ++++++ compat/fsmonitor/fsmonitor-fs-listen-win32.c | 21 +++++++++ compat/fsmonitor/fsmonitor-fs-listen.h | 49 ++++++++++++++++++++ config.mak.uname | 2 + contrib/buildsystems/CMakeLists.txt | 5 ++ 5 files changed, 90 insertions(+) create mode 100644 compat/fsmonitor/fsmonitor-fs-listen-win32.c create mode 100644 compat/fsmonitor/fsmonitor-fs-listen.h diff --git a/Makefile b/Makefile index 8fe1e42a435f59..c647fa7debac15 100644 --- a/Makefile +++ b/Makefile @@ -467,6 +467,11 @@ all:: # directory, and the JSON compilation database 'compile_commands.json' will be # created at the root of the repository. # +# If your platform supports an built-in fsmonitor backend, set +# FSMONITOR_DAEMON_BACKEND to the name of the corresponding +# `compat/fsmonitor/fsmonitor-fs-listen-.c` that implements the +# `fsmonitor_fs_listen__*()` routines. +# # Define DEVELOPER to enable more compiler warnings. Compiler version # and family are auto detected, but could be overridden by defining # COMPILER_FEATURES (see config.mak.dev). You can still set @@ -1928,6 +1933,11 @@ ifdef NEED_ACCESS_ROOT_HANDLER COMPAT_OBJS += compat/access.o endif +ifdef FSMONITOR_DAEMON_BACKEND + COMPAT_CFLAGS += -DHAVE_FSMONITOR_DAEMON_BACKEND + COMPAT_OBJS += compat/fsmonitor/fsmonitor-fs-listen-$(FSMONITOR_DAEMON_BACKEND).o +endif + ifeq ($(TCLTK_PATH),) NO_TCLTK = NoThanks endif @@ -2792,6 +2802,9 @@ GIT-BUILD-OPTIONS: FORCE @echo PAGER_ENV=\''$(subst ','\'',$(subst ','\'',$(PAGER_ENV)))'\' >>$@+ @echo DC_SHA1=\''$(subst ','\'',$(subst ','\'',$(DC_SHA1)))'\' >>$@+ @echo X=\'$(X)\' >>$@+ +ifdef FSMONITOR_DAEMON_BACKEND + @echo FSMONITOR_DAEMON_BACKEND=\''$(subst ','\'',$(subst ','\'',$(FSMONITOR_DAEMON_BACKEND)))'\' >>$@+ +endif ifdef TEST_OUTPUT_DIRECTORY @echo TEST_OUTPUT_DIRECTORY=\''$(subst ','\'',$(subst ','\'',$(TEST_OUTPUT_DIRECTORY)))'\' >>$@+ endif diff --git a/compat/fsmonitor/fsmonitor-fs-listen-win32.c b/compat/fsmonitor/fsmonitor-fs-listen-win32.c new file mode 100644 index 00000000000000..880446b49e35fb --- /dev/null +++ b/compat/fsmonitor/fsmonitor-fs-listen-win32.c @@ -0,0 +1,21 @@ +#include "cache.h" +#include "config.h" +#include "fsmonitor.h" +#include "fsmonitor-fs-listen.h" + +void fsmonitor_fs_listen__stop_async(struct fsmonitor_daemon_state *state) +{ +} + +void fsmonitor_fs_listen__loop(struct fsmonitor_daemon_state *state) +{ +} + +int fsmonitor_fs_listen__ctor(struct fsmonitor_daemon_state *state) +{ + return -1; +} + +void fsmonitor_fs_listen__dtor(struct fsmonitor_daemon_state *state) +{ +} diff --git a/compat/fsmonitor/fsmonitor-fs-listen.h b/compat/fsmonitor/fsmonitor-fs-listen.h new file mode 100644 index 00000000000000..c7b5776b3b60b6 --- /dev/null +++ b/compat/fsmonitor/fsmonitor-fs-listen.h @@ -0,0 +1,49 @@ +#ifndef FSMONITOR_FS_LISTEN_H +#define FSMONITOR_FS_LISTEN_H + +/* This needs to be implemented by each backend */ + +#ifdef HAVE_FSMONITOR_DAEMON_BACKEND + +struct fsmonitor_daemon_state; + +/* + * Initialize platform-specific data for the fsmonitor listener thread. + * This will be called from the main thread PRIOR to staring the + * fsmonitor_fs_listener thread. + * + * Returns 0 if successful. + * Returns -1 otherwise. + */ +int fsmonitor_fs_listen__ctor(struct fsmonitor_daemon_state *state); + +/* + * Cleanup platform-specific data for the fsmonitor listener thread. + * This will be called from the main thread AFTER joining the listener. + */ +void fsmonitor_fs_listen__dtor(struct fsmonitor_daemon_state *state); + +/* + * The main body of the platform-specific event loop to watch for + * filesystem events. This will run in the fsmonitor_fs_listen thread. + * + * It should call `ipc_server_stop_async()` if the listener thread + * prematurely terminates (because of a filesystem error or if it + * detects that the .git directory has been deleted). (It should NOT + * do so if the listener thread receives a normal shutdown signal from + * the IPC layer.) + * + * It should set `state->error_code` to -1 if the daemon should exit + * with an error. + */ +void fsmonitor_fs_listen__loop(struct fsmonitor_daemon_state *state); + +/* + * Gently request that the fsmonitor listener thread shutdown. + * It does not wait for it to stop. The caller should do a JOIN + * to wait for it. + */ +void fsmonitor_fs_listen__stop_async(struct fsmonitor_daemon_state *state); + +#endif /* HAVE_FSMONITOR_DAEMON_BACKEND */ +#endif /* FSMONITOR_FS_LISTEN_H */ diff --git a/config.mak.uname b/config.mak.uname index cb443b4e023adb..fcd88b60b14a11 100644 --- a/config.mak.uname +++ b/config.mak.uname @@ -420,6 +420,7 @@ ifeq ($(uname_S),Windows) # so we don't need this: # # SNPRINTF_RETURNS_BOGUS = YesPlease + FSMONITOR_DAEMON_BACKEND = win32 NO_SVN_TESTS = YesPlease RUNTIME_PREFIX = YesPlease HAVE_WPGMPTR = YesWeDo @@ -598,6 +599,7 @@ ifneq (,$(findstring MINGW,$(uname_S))) NO_STRTOUMAX = YesPlease NO_MKDTEMP = YesPlease NO_SVN_TESTS = YesPlease + FSMONITOR_DAEMON_BACKEND = win32 RUNTIME_PREFIX = YesPlease HAVE_WPGMPTR = YesWeDo NO_ST_BLOCKS_IN_STRUCT_STAT = YesPlease diff --git a/contrib/buildsystems/CMakeLists.txt b/contrib/buildsystems/CMakeLists.txt index a87841340e6a27..1ab94eb284f6f5 100644 --- a/contrib/buildsystems/CMakeLists.txt +++ b/contrib/buildsystems/CMakeLists.txt @@ -263,6 +263,11 @@ else() endif() endif() +if(CMAKE_SYSTEM_NAME STREQUAL "Windows") + add_compile_definitions(HAVE_FSMONITOR_DAEMON_BACKEND) + list(APPEND compat_SOURCES compat/fsmonitor/fsmonitor-fs-listen-win32.c) +endif() + set(EXE_EXTENSION ${CMAKE_EXECUTABLE_SUFFIX}) #header checks From 183c5556d2a45f063200f60b9868424605c44a22 Mon Sep 17 00:00:00 2001 From: Jeff Hostetler Date: Thu, 17 Dec 2020 10:41:07 -0500 Subject: [PATCH 08/25] fsmonitor-fs-listen-macos: stub in backend for MacOS Stub in empty implementation of fsmonitor--daemon backend for MacOS. Signed-off-by: Jeff Hostetler --- compat/fsmonitor/fsmonitor-fs-listen-macos.c | 20 ++++++++++++++++++++ config.mak.uname | 2 ++ contrib/buildsystems/CMakeLists.txt | 3 +++ 3 files changed, 25 insertions(+) create mode 100644 compat/fsmonitor/fsmonitor-fs-listen-macos.c diff --git a/compat/fsmonitor/fsmonitor-fs-listen-macos.c b/compat/fsmonitor/fsmonitor-fs-listen-macos.c new file mode 100644 index 00000000000000..b91058d1c4f820 --- /dev/null +++ b/compat/fsmonitor/fsmonitor-fs-listen-macos.c @@ -0,0 +1,20 @@ +#include "cache.h" +#include "fsmonitor.h" +#include "fsmonitor-fs-listen.h" + +int fsmonitor_fs_listen__ctor(struct fsmonitor_daemon_state *state) +{ + return -1; +} + +void fsmonitor_fs_listen__dtor(struct fsmonitor_daemon_state *state) +{ +} + +void fsmonitor_fs_listen__stop_async(struct fsmonitor_daemon_state *state) +{ +} + +void fsmonitor_fs_listen__loop(struct fsmonitor_daemon_state *state) +{ +} diff --git a/config.mak.uname b/config.mak.uname index fcd88b60b14a11..394355463e1e8a 100644 --- a/config.mak.uname +++ b/config.mak.uname @@ -147,6 +147,8 @@ ifeq ($(uname_S),Darwin) MSGFMT = /usr/local/opt/gettext/bin/msgfmt endif endif + FSMONITOR_DAEMON_BACKEND = macos + BASIC_LDFLAGS += -framework CoreServices endif ifeq ($(uname_S),SunOS) NEEDS_SOCKET = YesPlease diff --git a/contrib/buildsystems/CMakeLists.txt b/contrib/buildsystems/CMakeLists.txt index 1ab94eb284f6f5..aa80671045a032 100644 --- a/contrib/buildsystems/CMakeLists.txt +++ b/contrib/buildsystems/CMakeLists.txt @@ -266,6 +266,9 @@ endif() if(CMAKE_SYSTEM_NAME STREQUAL "Windows") add_compile_definitions(HAVE_FSMONITOR_DAEMON_BACKEND) list(APPEND compat_SOURCES compat/fsmonitor/fsmonitor-fs-listen-win32.c) +elseif(CMAKE_SYSTEM_NAME STREQUAL "Darwin") + add_compile_definitions(HAVE_FSMONITOR_DAEMON_BACKEND) + list(APPEND compat_SOURCES compat/fsmonitor/fsmonitor-fs-listen-macos.c) endif() set(EXE_EXTENSION ${CMAKE_EXECUTABLE_SUFFIX}) From 53d113874b3e2bb0604fd4df16b063bf48e9070b Mon Sep 17 00:00:00 2001 From: Jeff Hostetler Date: Thu, 17 Dec 2020 11:34:13 -0500 Subject: [PATCH 09/25] fsmonitor--daemon: implement daemon command options 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 --- builtin/fsmonitor--daemon.c | 395 +++++++++++++++++++++++++++++++++++- fsmonitor--daemon.h | 36 ++++ 2 files changed, 430 insertions(+), 1 deletion(-) create mode 100644 fsmonitor--daemon.h diff --git a/builtin/fsmonitor--daemon.c b/builtin/fsmonitor--daemon.c index 10434bce4b646e..23a06370797202 100644 --- a/builtin/fsmonitor--daemon.c +++ b/builtin/fsmonitor--daemon.c @@ -3,10 +3,14 @@ #include "parse-options.h" #include "fsmonitor.h" #include "fsmonitor-ipc.h" +#include "compat/fsmonitor/fsmonitor-fs-listen.h" +#include "fsmonitor--daemon.h" #include "simple-ipc.h" #include "khash.h" static const char * const builtin_fsmonitor__daemon_usage[] = { + N_("git fsmonitor--daemon --start []"), + N_("git fsmonitor--daemon --run []"), N_("git fsmonitor--daemon --stop"), N_("git fsmonitor--daemon --is-running"), N_("git fsmonitor--daemon --query "), @@ -16,6 +20,38 @@ static const char * const builtin_fsmonitor__daemon_usage[] = { }; #ifdef HAVE_FSMONITOR_DAEMON_BACKEND +/* + * Global state loaded from config. + */ +#define FSMONITOR__IPC_THREADS "fsmonitor.ipcthreads" +static int fsmonitor__ipc_threads = 8; + +#define FSMONITOR__START_TIMEOUT "fsmonitor.starttimeout" +static int fsmonitor__start_timeout_sec = 60; + +static int fsmonitor_config(const char *var, const char *value, void *cb) +{ + if (!strcmp(var, FSMONITOR__IPC_THREADS)) { + int i = git_config_int(var, value); + if (i < 1) + return error(_("value of '%s' out of range: %d"), + FSMONITOR__IPC_THREADS, i); + fsmonitor__ipc_threads = i; + return 0; + } + + if (!strcmp(var, FSMONITOR__START_TIMEOUT)) { + int i = git_config_int(var, value); + if (i < 0) + return error(_("value of '%s' out of range: %d"), + FSMONITOR__START_TIMEOUT, i); + fsmonitor__start_timeout_sec = i; + return 0; + } + + return git_default_config(var, value, cb); +} + /* * Acting as a CLIENT. * @@ -113,15 +149,350 @@ static int do_as_client__send_flush(void) return 0; } +static ipc_server_application_cb handle_client; + +static int handle_client(void *data, const char *command, + ipc_server_reply_cb *reply, + struct ipc_server_reply_data *reply_data) +{ + /* struct fsmonitor_daemon_state *state = data; */ + int result; + + trace2_region_enter("fsmonitor", "handle_client", the_repository); + trace2_data_string("fsmonitor", the_repository, "request", command); + + result = 0; /* TODO Do something here. */ + + trace2_region_leave("fsmonitor", "handle_client", the_repository); + + return result; +} + +static void *fsmonitor_fs_listen__thread_proc(void *_state) +{ + struct fsmonitor_daemon_state *state = _state; + + trace2_thread_start("fsm-listen"); + + trace_printf_key(&trace_fsmonitor, "Watching: worktree '%s'", + state->path_worktree_watch.buf); + if (state->nr_paths_watching > 1) + trace_printf_key(&trace_fsmonitor, "Watching: gitdir '%s'", + state->path_gitdir_watch.buf); + + fsmonitor_fs_listen__loop(state); + + trace2_thread_exit(); + return NULL; +} + +static int fsmonitor_run_daemon_1(struct fsmonitor_daemon_state *state) +{ + struct ipc_server_opts ipc_opts = { + .nr_threads = fsmonitor__ipc_threads, + + /* + * We know that there are no other active threads yet, + * so we can let the IPC layer temporarily chdir() if + * it needs to when creating the server side of the + * Unix domain socket. + */ + .uds_disallow_chdir = 0 + }; + + /* + * Start the IPC thread pool before the we've started the file + * system event listener thread so that we have the IPC handle + * before we need it. + */ + if (ipc_server_run_async(&state->ipc_server_data, + fsmonitor_ipc__get_path(), &ipc_opts, + handle_client, state)) + return error(_("could not start IPC thread pool")); + + /* + * Start the fsmonitor listener thread to collect filesystem + * events. + */ + if (pthread_create(&state->listener_thread, NULL, + fsmonitor_fs_listen__thread_proc, state) < 0) { + ipc_server_stop_async(state->ipc_server_data); + ipc_server_await(state->ipc_server_data); + + return error(_("could not start fsmonitor listener thread")); + } + + /* + * The daemon is now fully functional in background threads. + * Wait for the IPC thread pool to shutdown (whether by client + * request or from filesystem activity). + */ + ipc_server_await(state->ipc_server_data); + + /* + * The fsmonitor listener thread may have received a shutdown + * event from the IPC thread pool, but it doesn't hurt to tell + * it again. And wait for it to shutdown. + */ + fsmonitor_fs_listen__stop_async(state); + pthread_join(state->listener_thread, NULL); + + return state->error_code; +} + +static int fsmonitor_run_daemon(void) +{ + struct fsmonitor_daemon_state state; + int err; + + memset(&state, 0, sizeof(state)); + + pthread_mutex_init(&state.main_lock, NULL); + state.error_code = 0; + state.current_token_data = NULL; + state.test_client_delay_ms = 0; + + /* Prepare to (recursively) watch the directory. */ + strbuf_init(&state.path_worktree_watch, 0); + strbuf_addstr(&state.path_worktree_watch, absolute_path(get_git_work_tree())); + state.nr_paths_watching = 1; + + /* + * If ".git" is not a directory, then is not inside the + * cone of , so set up a second watch for it. + */ + strbuf_init(&state.path_gitdir_watch, 0); + strbuf_addbuf(&state.path_gitdir_watch, &state.path_worktree_watch); + strbuf_addstr(&state.path_gitdir_watch, "/.git"); + if (!is_directory(state.path_gitdir_watch.buf)) { + strbuf_reset(&state.path_gitdir_watch); + strbuf_addstr(&state.path_gitdir_watch, absolute_path(get_git_dir())); + state.nr_paths_watching = 2; + } + + /* + * Confirm that we can create platform-specific resources for the + * filesystem listener before we bother starting all the threads. + */ + if (fsmonitor_fs_listen__ctor(&state)) { + err = error(_("could not initialize listener thread")); + goto done; + } + + err = fsmonitor_run_daemon_1(&state); + +done: + pthread_mutex_destroy(&state.main_lock); + fsmonitor_fs_listen__dtor(&state); + + ipc_server_free(state.ipc_server_data); + + strbuf_release(&state.path_worktree_watch); + strbuf_release(&state.path_gitdir_watch); + + return err; +} + static int is_ipc_daemon_listening(void) { return fsmonitor_ipc__get_state() == IPC_STATE__LISTENING; } +static int try_to_run_foreground_daemon(void) +{ + /* + * Technically, we don't need to probe for an existing daemon + * process, since we could just call `fsmonitor_run_daemon()` + * and let it fail if the pipe/socket is busy. + * + * However, this method gives us a nicer error message for a + * common error case. + */ + if (is_ipc_daemon_listening()) + die("fsmonitor--daemon is already running."); + + return !!fsmonitor_run_daemon(); +} + +#ifndef GIT_WINDOWS_NATIVE +/* + * This is adapted from `daemonize()`. Use `fork()` to directly create + * and run the daemon in a child process. The fork-parent returns the + * child PID so that we can wait for the child to startup before exiting. + */ +static int spawn_background_fsmonitor_daemon(pid_t *pid) +{ + *pid = fork(); + + switch (*pid) { + case 0: + if (setsid() == -1) + error_errno(_("setsid failed")); + close(0); + close(1); + close(2); + sanitize_stdfds(); + + return !!fsmonitor_run_daemon(); + + case -1: + return error_errno(_("could not spawn fsmonitor--daemon in the background")); + + default: + return 0; + } +} +#else +/* + * Conceptually like `daemonize()` but different because Windows does not + * have `fork(2)`. Spawn a normal Windows child process but without the + * limitations of `start_command()` and `finish_command()`. + */ +static int spawn_background_fsmonitor_daemon(pid_t *pid) +{ + char git_exe[MAX_PATH]; + struct strvec args = STRVEC_INIT; + int in, out; + + GetModuleFileNameA(NULL, git_exe, MAX_PATH); + + in = open("/dev/null", O_RDONLY); + out = open("/dev/null", O_WRONLY); + + strvec_push(&args, git_exe); + strvec_push(&args, "fsmonitor--daemon"); + strvec_push(&args, "--run"); + + *pid = mingw_spawnvpe(args.v[0], args.v, NULL, NULL, in, out, out); + close(in); + close(out); + + strvec_clear(&args); + + if (*pid < 0) + return error(_("could not spawn fsmonitor--daemon in the background")); + + return 0; +} +#endif + +/* + * This is adapted from `wait_or_whine()`. Watch the child process and + * let it get started and begin listening for requests on the socket + * before reporting our success. + */ +static int wait_for_background_startup(pid_t pid_child) +{ + int status; + pid_t pid_seen; + enum ipc_active_state s; + time_t time_limit, now; + + time(&time_limit); + time_limit += fsmonitor__start_timeout_sec; + + for (;;) { + pid_seen = waitpid(pid_child, &status, WNOHANG); + + if (pid_seen == -1) + return error_errno(_("waitpid failed")); + + else if (pid_seen == 0) { + /* + * The child is still running (this should be + * the normal case). Try to connect to it on + * the socket and see if it is ready for + * business. + * + * If there is another daemon already running, + * our child will fail to start (possibly + * after a timeout on the lock), but we don't + * care (who responds) if the socket is live. + */ + s = fsmonitor_ipc__get_state(); + if (s == IPC_STATE__LISTENING) + return 0; + + time(&now); + if (now > time_limit) + return error(_("fsmonitor--daemon not online yet")); + + continue; + } + + else if (pid_seen == pid_child) { + /* + * The new child daemon process shutdown while + * it was starting up, so it is not listening + * on the socket. + * + * Try to ping the socket in the odd chance + * that another daemon started (or was already + * running) while our child was starting. + * + * Again, we don't care who services the socket. + */ + s = fsmonitor_ipc__get_state(); + if (s == IPC_STATE__LISTENING) + return 0; + + /* + * We don't care about the WEXITSTATUS() nor + * any of the WIF*(status) values because + * `cmd_fsmonitor__daemon()` does the `!!result` + * trick on all function return values. + * + * So it is sufficient to just report the + * early shutdown as an error. + */ + return error(_("fsmonitor--daemon failed to start")); + } + + else + return error(_("waitpid is confused")); + } +} + +static int try_to_start_background_daemon(void) +{ + pid_t pid_child; + int ret; + + /* + * Before we try to create a background daemon process, see + * if a daemon process is already listening. This makes it + * easier for us to report an already-listening error to the + * console, since our spawn/daemon can only report the success + * of creating the background process (and not whether it + * immediately exited). + */ + if (is_ipc_daemon_listening()) + die("fsmonitor--daemon is already running."); + + /* + * Run the actual daemon in a background process. + */ + ret = spawn_background_fsmonitor_daemon(&pid_child); + if (pid_child <= 0) + return ret; + + /* + * Wait (with timeout) for the background child process get + * started and begin listening on the socket/pipe. This makes + * the "start" command more synchronous and more reliable in + * tests. + */ + ret = wait_for_background_startup(pid_child); + + return ret; +} + int cmd_fsmonitor__daemon(int argc, const char **argv, const char *prefix) { enum daemon_mode { UNDEFINED_MODE, + START, + RUN, STOP, IS_RUNNING, QUERY, @@ -130,6 +501,11 @@ int cmd_fsmonitor__daemon(int argc, const char **argv, const char *prefix) } mode = UNDEFINED_MODE; struct option options[] = { + OPT_CMDMODE(0, "start", &mode, + N_("run the daemon in the background"), + START), + OPT_CMDMODE(0, "run", &mode, + N_("run the daemon in the foreground"), RUN), OPT_CMDMODE(0, "stop", &mode, N_("stop the running daemon"), STOP), @@ -145,18 +521,35 @@ int cmd_fsmonitor__daemon(int argc, const char **argv, const char *prefix) QUERY_INDEX), OPT_CMDMODE(0, "flush", &mode, N_("flush cached filesystem events"), FLUSH), + + OPT_GROUP(N_("Daemon options")), + OPT_INTEGER(0, "ipc-threads", + &fsmonitor__ipc_threads, + N_("use ipc worker threads")), + OPT_INTEGER(0, "start-timeout", + &fsmonitor__start_timeout_sec, + N_("Max seconds to wait for background daemon startup")), OPT_END() }; if (argc == 2 && !strcmp(argv[1], "-h")) usage_with_options(builtin_fsmonitor__daemon_usage, options); - git_config(git_default_config, NULL); + git_config(fsmonitor_config, NULL); argc = parse_options(argc, argv, prefix, options, builtin_fsmonitor__daemon_usage, 0); + if (fsmonitor__ipc_threads < 1) + die(_("invalid 'ipc-threads' value (%d)"), + fsmonitor__ipc_threads); switch (mode) { + case START: + return !!try_to_start_background_daemon(); + + case RUN: + return !!try_to_run_foreground_daemon(); + case STOP: return !!do_as_client__send_stop(); diff --git a/fsmonitor--daemon.h b/fsmonitor--daemon.h new file mode 100644 index 00000000000000..09e4a6fb6675d3 --- /dev/null +++ b/fsmonitor--daemon.h @@ -0,0 +1,36 @@ +#ifndef FSMONITOR_DAEMON_H +#define FSMONITOR_DAEMON_H + +#ifdef HAVE_FSMONITOR_DAEMON_BACKEND + +#include "cache.h" +#include "dir.h" +#include "run-command.h" +#include "simple-ipc.h" +#include "thread-utils.h" + +struct fsmonitor_batch; +struct fsmonitor_token_data; + +struct fsmonitor_daemon_backend_data; /* opaque platform-specific data */ + +struct fsmonitor_daemon_state { + pthread_t listener_thread; + pthread_mutex_t main_lock; + + struct strbuf path_worktree_watch; + struct strbuf path_gitdir_watch; + int nr_paths_watching; + + struct fsmonitor_token_data *current_token_data; + + int error_code; + struct fsmonitor_daemon_backend_data *backend_data; + + struct ipc_server_data *ipc_server_data; + + int test_client_delay_ms; +}; + +#endif /* HAVE_FSMONITOR_DAEMON_BACKEND */ +#endif /* FSMONITOR_DAEMON_H */ From b236c0b6d5ba89aa6cd455630869ef777c532dfe Mon Sep 17 00:00:00 2001 From: Jeff Hostetler Date: Thu, 17 Dec 2020 12:37:15 -0500 Subject: [PATCH 10/25] 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. 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 --- builtin/fsmonitor--daemon.c | 81 +++++++++++++++++++++++++++++++++++++ fsmonitor--daemon.h | 61 ++++++++++++++++++++++++++++ 2 files changed, 142 insertions(+) diff --git a/builtin/fsmonitor--daemon.c b/builtin/fsmonitor--daemon.c index 23a06370797202..16252487240a3c 100644 --- a/builtin/fsmonitor--daemon.c +++ b/builtin/fsmonitor--daemon.c @@ -168,6 +168,87 @@ static int handle_client(void *data, const char *command, return result; } +#define FSMONITOR_COOKIE_PREFIX ".fsmonitor-daemon-" + +enum fsmonitor_path_type fsmonitor_classify_path_workdir_relative( + const char *rel) +{ + if (fspathncmp(rel, ".git", 4)) + return IS_WORKDIR_PATH; + rel += 4; + + if (!*rel) + return IS_DOT_GIT; + if (*rel != '/') + return IS_WORKDIR_PATH; /* e.g. .gitignore */ + rel++; + + if (!fspathncmp(rel, FSMONITOR_COOKIE_PREFIX, + strlen(FSMONITOR_COOKIE_PREFIX))) + return IS_INSIDE_DOT_GIT_WITH_COOKIE_PREFIX; + + return IS_INSIDE_DOT_GIT; +} + +enum fsmonitor_path_type fsmonitor_classify_path_gitdir_relative( + const char *rel) +{ + if (!fspathncmp(rel, FSMONITOR_COOKIE_PREFIX, + strlen(FSMONITOR_COOKIE_PREFIX))) + return IS_INSIDE_GITDIR_WITH_COOKIE_PREFIX; + + return IS_INSIDE_GITDIR; +} + +static enum fsmonitor_path_type try_classify_workdir_abs_path( + struct fsmonitor_daemon_state *state, + const char *path) +{ + const char *rel; + + if (fspathncmp(path, state->path_worktree_watch.buf, + state->path_worktree_watch.len)) + return IS_OUTSIDE_CONE; + + rel = path + state->path_worktree_watch.len; + + if (!*rel) + return IS_WORKDIR_PATH; /* it is the root dir exactly */ + if (*rel != '/') + return IS_OUTSIDE_CONE; + rel++; + + return fsmonitor_classify_path_workdir_relative(rel); +} + +enum fsmonitor_path_type fsmonitor_classify_path_absolute( + struct fsmonitor_daemon_state *state, + const char *path) +{ + const char *rel; + enum fsmonitor_path_type t; + + t = try_classify_workdir_abs_path(state, path); + if (state->nr_paths_watching == 1) + return t; + if (t != IS_OUTSIDE_CONE) + return t; + + if (fspathncmp(path, state->path_gitdir_watch.buf, + state->path_gitdir_watch.len)) + return IS_OUTSIDE_CONE; + + rel = path + state->path_gitdir_watch.len; + + if (!*rel) + return IS_GITDIR; /* it is the exactly */ + if (*rel != '/') + return IS_OUTSIDE_CONE; + rel++; + + return fsmonitor_classify_path_gitdir_relative(rel); +} + static void *fsmonitor_fs_listen__thread_proc(void *_state) { struct fsmonitor_daemon_state *state = _state; diff --git a/fsmonitor--daemon.h b/fsmonitor--daemon.h index 09e4a6fb6675d3..97ea3766e900a4 100644 --- a/fsmonitor--daemon.h +++ b/fsmonitor--daemon.h @@ -32,5 +32,66 @@ struct fsmonitor_daemon_state { int test_client_delay_ms; }; +/* + * Pathname classifications. + * + * The daemon classifies the pathnames that it receives from file + * system notification events into the following categories and uses + * that to decide whether clients are told about them. (And to watch + * for file system synchronization events.) + * + * The client should only care about paths within the working + * directory proper (inside the working directory and not ".git" nor + * inside of ".git/"). That is, the client has read the index and is + * asking for a list of any paths in the working directory that have + * been modified since the last token. The client does not care about + * file system changes within the .git directory (such as new loose + * objects or packfiles). So the client will only receive paths that + * are classified as IS_WORKDIR_PATH. + * + * The daemon uses the IS_DOT_GIT and IS_GITDIR internally to mean the + * exact ".git" directory or GITDIR. If the daemon receives a delete + * event for either of these directories, it will automatically + * shutdown, for example. + * + * Note that the daemon DOES NOT explicitly watch nor special case the + * ".git/index" file. The daemon does not read the index and does not + * have any internal index-relative state. The daemon only collects + * the set of modified paths within the working directory. + */ +enum fsmonitor_path_type { + IS_WORKDIR_PATH = 0, + + IS_DOT_GIT, + IS_INSIDE_DOT_GIT, + IS_INSIDE_DOT_GIT_WITH_COOKIE_PREFIX, + + IS_GITDIR, + IS_INSIDE_GITDIR, + IS_INSIDE_GITDIR_WITH_COOKIE_PREFIX, + + IS_OUTSIDE_CONE, +}; + +/* + * Classify a pathname relative to the root of the working directory. + */ +enum fsmonitor_path_type fsmonitor_classify_path_workdir_relative( + const char *relative_path); + +/* + * Classify a pathname relative to a that is external to the + * worktree directory. + */ +enum fsmonitor_path_type fsmonitor_classify_path_gitdir_relative( + const char *relative_path); + +/* + * Classify an absolute pathname received from a filesystem event. + */ +enum fsmonitor_path_type fsmonitor_classify_path_absolute( + struct fsmonitor_daemon_state *state, + const char *path); + #endif /* HAVE_FSMONITOR_DAEMON_BACKEND */ #endif /* FSMONITOR_DAEMON_H */ From 04b9f8cda257b3a2a182fa1a0f03370c0e152cc5 Mon Sep 17 00:00:00 2001 From: Jeff Hostetler Date: Thu, 17 Dec 2020 12:58:14 -0500 Subject: [PATCH 11/25] fsmonitor--daemon: define token-ids Teach fsmonitor--daemon to create token-ids and define the overall token naming scheme. Signed-off-by: Jeff Hostetler --- builtin/fsmonitor--daemon.c | 108 +++++++++++++++++++++++++++++++++++- 1 file changed, 107 insertions(+), 1 deletion(-) diff --git a/builtin/fsmonitor--daemon.c b/builtin/fsmonitor--daemon.c index 16252487240a3c..2d25e36601fedf 100644 --- a/builtin/fsmonitor--daemon.c +++ b/builtin/fsmonitor--daemon.c @@ -149,6 +149,112 @@ static int do_as_client__send_flush(void) return 0; } +/* + * Requests to and from a FSMonitor Protocol V2 provider use an opaque + * "token" as a virtual timestamp. Clients can request a summary of all + * created/deleted/modified files relative to a token. In the response, + * clients receive a new token for the next (relative) request. + * + * + * Token Format + * ============ + * + * The contents of the token are private and provider-specific. + * + * For the built-in fsmonitor--daemon, we define a token as follows: + * + * "builtin" ":" ":" + * + * The is an arbitrary OPAQUE string, such as a GUID, + * UUID, or {timestamp,pid}. It is used to group all filesystem + * events that happened while the daemon was monitoring (and in-sync + * with the filesystem). + * + * Unlike FSMonitor Protocol V1, it is not defined as a timestamp + * and does not define less-than/greater-than relationships. + * (There are too many race conditions to rely on file system + * event timestamps.) + * + * The is a simple integer incremented for each event + * received. When a new is created, the is + * reset to zero. + * + * + * About Token Ids + * =============== + * + * A new token_id is created: + * + * [1] each time the daemon is started. + * + * [2] any time that the daemon must re-sync with the filesystem + * (such as when the kernel drops or we miss events on a very + * active volume). + * + * [3] in response to a client "flush" command (for dropped event + * testing). + * + * [4] MAYBE We might want to change the token_id after very complex + * filesystem operations are performed, such as a directory move + * sequence that affects many files within. It might be simpler + * to just give up and fake a re-sync (and let the client do a + * full scan) than try to enumerate the effects of such a change. + * + * When a new token_id is created, the daemon is free to discard all + * cached filesystem events associated with any previous token_ids. + * Events associated with a non-current token_id will never be sent + * to a client. A token_id change implicitly means that the daemon + * has gap in its event history. + * + * Therefore, clients that present a token with a stale (non-current) + * token_id will always be given a trivial response. + */ +struct fsmonitor_token_data { + struct strbuf token_id; + struct fsmonitor_batch *batch_head; + struct fsmonitor_batch *batch_tail; + uint64_t client_ref_count; +}; + +static struct fsmonitor_token_data *fsmonitor_new_token_data(void) +{ + static int test_env_value = -1; + static uint64_t flush_count = 0; + struct fsmonitor_token_data *token; + + token = (struct fsmonitor_token_data *)xcalloc(1, sizeof(*token)); + + strbuf_init(&token->token_id, 0); + token->batch_head = NULL; + token->batch_tail = NULL; + token->client_ref_count = 0; + + if (test_env_value < 0) + test_env_value = git_env_bool("GIT_TEST_FSMONITOR_TOKEN", 0); + + if (!test_env_value) { + struct timeval tv; + struct tm tm; + time_t secs; + + gettimeofday(&tv, NULL); + secs = tv.tv_sec; + gmtime_r(&secs, &tm); + + strbuf_addf(&token->token_id, + "%"PRIu64".%d.%4d%02d%02dT%02d%02d%02d.%06ldZ", + flush_count++, + getpid(), + tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, + tm.tm_hour, tm.tm_min, tm.tm_sec, + (long)tv.tv_usec); + } else { + strbuf_addf(&token->token_id, "test_%08x", test_env_value++); + } + + return token; +} + static ipc_server_application_cb handle_client; static int handle_client(void *data, const char *command, @@ -330,7 +436,7 @@ static int fsmonitor_run_daemon(void) pthread_mutex_init(&state.main_lock, NULL); state.error_code = 0; - state.current_token_data = NULL; + state.current_token_data = fsmonitor_new_token_data(); state.test_client_delay_ms = 0; /* Prepare to (recursively) watch the directory. */ From 1533522d2b36842bbba7211d6d168091b586e7c3 Mon Sep 17 00:00:00 2001 From: Jeff Hostetler Date: Thu, 17 Dec 2020 13:17:33 -0500 Subject: [PATCH 12/25] fsmonitor--daemon: create token-based changed path cache Teach fsmonitor--daemon to build lists 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 event loops receive batches containing one or more changed paths. Their fs listener thread will accumulate them in a `fsmonitor_batch` (and without locking) and then "publish" them to associate them with the current token and to make them visible to the client worker threads. Signed-off-by: Jeff Hostetler --- builtin/fsmonitor--daemon.c | 192 ++++++++++++++++++++++++++++++++++++ fsmonitor--daemon.h | 40 ++++++++ 2 files changed, 232 insertions(+) diff --git a/builtin/fsmonitor--daemon.c b/builtin/fsmonitor--daemon.c index 2d25e36601fedf..48071d445c4922 100644 --- a/builtin/fsmonitor--daemon.c +++ b/builtin/fsmonitor--daemon.c @@ -255,6 +255,120 @@ static struct fsmonitor_token_data *fsmonitor_new_token_data(void) return token; } +struct fsmonitor_batch { + struct fsmonitor_batch *next; + uint64_t batch_seq_nr; + const char **interned_paths; + size_t nr, alloc; + time_t pinned_time; +}; + +struct fsmonitor_batch *fsmonitor_batch__new(void) +{ + struct fsmonitor_batch *batch = xcalloc(1, sizeof(*batch)); + + return batch; +} + +struct fsmonitor_batch *fsmonitor_batch__free(struct fsmonitor_batch *batch) +{ + struct fsmonitor_batch *next; + + if (!batch) + return NULL; + + next = batch->next; + + /* + * The actual strings within the array are interned, so we don't + * own them. + */ + free(batch->interned_paths); + + return next; +} + +void fsmonitor_batch__add_path(struct fsmonitor_batch *batch, + const char *path) +{ + const char *interned_path = strintern(path); + + trace_printf_key(&trace_fsmonitor, "event: %s", interned_path); + + ALLOC_GROW(batch->interned_paths, batch->nr + 1, batch->alloc); + batch->interned_paths[batch->nr++] = interned_path; +} + +static void fsmonitor_batch__combine(struct fsmonitor_batch *batch_dest, + const struct fsmonitor_batch *batch_src) +{ + /* assert state->main_lock */ + + size_t k; + + ALLOC_GROW(batch_dest->interned_paths, + batch_dest->nr + batch_src->nr + 1, + batch_dest->alloc); + + for (k = 0; k < batch_src->nr; k++) + batch_dest->interned_paths[batch_dest->nr++] = + batch_src->interned_paths[k]; +} + +static void fsmonitor_free_token_data(struct fsmonitor_token_data *token) +{ + struct fsmonitor_batch *p; + + if (!token) + return; + + assert(token->client_ref_count == 0); + + strbuf_release(&token->token_id); + + for (p = token->batch_head; p; p = fsmonitor_batch__free(p)) + ; + + free(token); +} + +/* + * Flush all of our cached data about the filesystem. Call this if we + * lose sync with the filesystem and miss some notification events. + * + * [1] If we are missing events, then we no longer have a complete + * history of the directory (relative to our current start token). + * We should create a new token and start fresh (as if we just + * booted up). + * + * If there are no readers of the the current token data series, we + * can free it now. Otherwise, let the last reader free it. Either + * way, the old token data series is no longer associated with our + * state data. + */ +void fsmonitor_force_resync(struct fsmonitor_daemon_state *state) +{ + struct fsmonitor_token_data *free_me = NULL; + struct fsmonitor_token_data *new_one = NULL; + + new_one = fsmonitor_new_token_data(); + + pthread_mutex_lock(&state->main_lock); + + trace_printf_key(&trace_fsmonitor, + "force resync [old '%s'][new '%s']", + state->current_token_data->token_id.buf, + new_one->token_id.buf); + + if (state->current_token_data->client_ref_count == 0) + free_me = state->current_token_data; + state->current_token_data = new_one; + + pthread_mutex_unlock(&state->main_lock); + + fsmonitor_free_token_data(free_me); +} + static ipc_server_application_cb handle_client; static int handle_client(void *data, const char *command, @@ -355,6 +469,77 @@ enum fsmonitor_path_type fsmonitor_classify_path_absolute( return fsmonitor_classify_path_gitdir_relative(rel); } +/* + * We try to combine small batches at the front of the batch-list to avoid + * having a long list. This hopefully makes it a little easier when we want + * to truncate and maintain the list. However, we don't want the paths array + * to just keep growing and growing with realloc, so we insert an arbitrary + * limit. + */ +#define MY_COMBINE_LIMIT (1024) + +void fsmonitor_publish(struct fsmonitor_daemon_state *state, + struct fsmonitor_batch *batch, + const struct string_list *cookie_names) +{ + if (!batch && !cookie_names->nr) + return; + + pthread_mutex_lock(&state->main_lock); + + if (batch) { + struct fsmonitor_batch *head; + + head = state->current_token_data->batch_head; + if (!head) { + batch->batch_seq_nr = 0; + batch->next = NULL; + state->current_token_data->batch_head = batch; + state->current_token_data->batch_tail = batch; + } else if (head->pinned_time) { + /* + * We cannot alter the current batch list + * because: + * + * [a] it is being transmitted to at least one + * client and the handle_client() thread has a + * ref-count, but not a lock on the batch list + * starting with this item. + * + * [b] it has been transmitted in the past to + * at least one client such that future + * requests are relative to this head batch. + * + * So, we can only prepend a new batch onto + * the front of the list. + */ + batch->batch_seq_nr = head->batch_seq_nr + 1; + batch->next = head; + state->current_token_data->batch_head = batch; + } else if (head->nr + batch->nr > MY_COMBINE_LIMIT) { + /* + * The head batch in the list has never been + * transmitted to a client, but folding the + * contents of the new batch onto it would + * exceed our arbitrary limit, so just prepend + * the new batch onto the list. + */ + batch->batch_seq_nr = head->batch_seq_nr + 1; + batch->next = head; + state->current_token_data->batch_head = batch; + } else { + /* + * We are free to append the paths in the given + * batch onto the end of the current head batch. + */ + fsmonitor_batch__combine(head, batch); + fsmonitor_batch__free(batch); + } + } + + pthread_mutex_unlock(&state->main_lock); +} + static void *fsmonitor_fs_listen__thread_proc(void *_state) { struct fsmonitor_daemon_state *state = _state; @@ -369,6 +554,13 @@ static void *fsmonitor_fs_listen__thread_proc(void *_state) fsmonitor_fs_listen__loop(state); + pthread_mutex_lock(&state->main_lock); + if (state->current_token_data && + state->current_token_data->client_ref_count == 0) + fsmonitor_free_token_data(state->current_token_data); + state->current_token_data = NULL; + pthread_mutex_unlock(&state->main_lock); + trace2_thread_exit(); return NULL; } diff --git a/fsmonitor--daemon.h b/fsmonitor--daemon.h index 97ea3766e900a4..06563b6ed56c0d 100644 --- a/fsmonitor--daemon.h +++ b/fsmonitor--daemon.h @@ -12,6 +12,27 @@ struct fsmonitor_batch; struct fsmonitor_token_data; +/* + * Create a new batch of path(s). The returned batch is considered + * private and not linked into the fsmonitor daemon state. The caller + * should fill this batch with one or more paths and then publish it. + */ +struct fsmonitor_batch *fsmonitor_batch__new(void); + +/* + * Free this batch and return the value of the batch->next field. + */ +struct fsmonitor_batch *fsmonitor_batch__free(struct fsmonitor_batch *batch); + +/* + * Add this path to this batch of modified files. + * + * The batch should be private and NOT (yet) linked into the fsmonitor + * daemon state and therefore not yet visible to worker threads and so + * no locking is required. + */ +void fsmonitor_batch__add_path(struct fsmonitor_batch *batch, const char *path); + struct fsmonitor_daemon_backend_data; /* opaque platform-specific data */ struct fsmonitor_daemon_state { @@ -93,5 +114,24 @@ enum fsmonitor_path_type fsmonitor_classify_path_absolute( struct fsmonitor_daemon_state *state, const char *path); +/* + * Prepend the this batch of path(s) onto the list of batches associated + * with the current token. This makes the batch visible to worker threads. + * + * The caller no longer owns the batch and must not free it. + * + * Wake up the client threads waiting on these cookies. + */ +void fsmonitor_publish(struct fsmonitor_daemon_state *state, + struct fsmonitor_batch *batch, + const struct string_list *cookie_names); + +/* + * If the platform-specific layer loses sync with the filesystem, + * it should call this to invalidate cached data and abort waiting + * threads. + */ +void fsmonitor_force_resync(struct fsmonitor_daemon_state *state); + #endif /* HAVE_FSMONITOR_DAEMON_BACKEND */ #endif /* FSMONITOR_DAEMON_H */ From 08199dd15df94b0326f049b94c2528c530845a96 Mon Sep 17 00:00:00 2001 From: Jeff Hostetler Date: Thu, 17 Dec 2020 13:34:30 -0500 Subject: [PATCH 13/25] fsmonitor-fs-listen-win32: implement FSMonitor backend on Windows Teach the win32 backend to register a watch on the working tree root directory (recursively). Also watch the if it is not inside the working tree. And to collect path change notifications into batches and publish. Signed-off-by: Jeff Hostetler --- compat/fsmonitor/fsmonitor-fs-listen-win32.c | 493 +++++++++++++++++++ 1 file changed, 493 insertions(+) diff --git a/compat/fsmonitor/fsmonitor-fs-listen-win32.c b/compat/fsmonitor/fsmonitor-fs-listen-win32.c index 880446b49e35fb..2f1fcf85a0a4ea 100644 --- a/compat/fsmonitor/fsmonitor-fs-listen-win32.c +++ b/compat/fsmonitor/fsmonitor-fs-listen-win32.c @@ -2,20 +2,513 @@ #include "config.h" #include "fsmonitor.h" #include "fsmonitor-fs-listen.h" +#include "fsmonitor--daemon.h" + +/* + * The documentation of ReadDirectoryChangesW() states that the maximum + * buffer size is 64K when the monitored directory is remote. + * + * Larger buffers may be used when the monitored directory is local and + * will help us receive events faster from the kernel and avoid dropped + * events. + * + * So we try to use a very large buffer and silently fallback to 64K if + * we get an error. + */ +#define MAX_RDCW_BUF_FALLBACK (65536) +#define MAX_RDCW_BUF (65536 * 8) + +struct one_watch +{ + char buffer[MAX_RDCW_BUF]; + DWORD buf_len; + DWORD count; + + struct strbuf path; + HANDLE hDir; + HANDLE hEvent; + OVERLAPPED overlapped; + + /* + * Is there an active ReadDirectoryChangesW() call pending. If so, we + * need to later call GetOverlappedResult() and possibly CancelIoEx(). + */ + BOOL is_active; +}; + +struct fsmonitor_daemon_backend_data +{ + struct one_watch *watch_worktree; + struct one_watch *watch_gitdir; + + HANDLE hEventShutdown; + + HANDLE hListener[3]; /* we don't own these handles */ +#define LISTENER_SHUTDOWN 0 +#define LISTENER_HAVE_DATA_WORKTREE 1 +#define LISTENER_HAVE_DATA_GITDIR 2 + int nr_listener_handles; +}; + +/* + * Convert the WCHAR path from the notification into UTF8 and + * then normalize it. + */ +static int normalize_path_in_utf8(FILE_NOTIFY_INFORMATION *info, + struct strbuf *normalized_path) +{ + int reserve; + int len = 0; + + strbuf_reset(normalized_path); + if (!info->FileNameLength) + goto normalize; + + /* + * Pre-reserve enough space in the UTF8 buffer for + * each Unicode WCHAR character to be mapped into a + * sequence of 2 UTF8 characters. That should let us + * avoid ERROR_INSUFFICIENT_BUFFER 99.9+% of the time. + */ + reserve = info->FileNameLength + 1; + strbuf_grow(normalized_path, reserve); + + for (;;) { + len = WideCharToMultiByte(CP_UTF8, 0, info->FileName, + info->FileNameLength / sizeof(WCHAR), + normalized_path->buf, + strbuf_avail(normalized_path) - 1, + NULL, NULL); + if (len > 0) + goto normalize; + if (GetLastError() != ERROR_INSUFFICIENT_BUFFER) { + error("[GLE %ld] could not convert path to UTF-8: '%.*ls'", + GetLastError(), + (int)(info->FileNameLength / sizeof(WCHAR)), + info->FileName); + return -1; + } + + strbuf_grow(normalized_path, + strbuf_avail(normalized_path) + reserve); + } + +normalize: + strbuf_setlen(normalized_path, len); + return strbuf_normalize_path(normalized_path); +} void fsmonitor_fs_listen__stop_async(struct fsmonitor_daemon_state *state) { + SetEvent(state->backend_data->hListener[LISTENER_SHUTDOWN]); +} + +static struct one_watch *create_watch(struct fsmonitor_daemon_state *state, + const char *path) +{ + struct one_watch *watch = NULL; + DWORD desired_access = FILE_LIST_DIRECTORY; + DWORD share_mode = + FILE_SHARE_WRITE | FILE_SHARE_READ | FILE_SHARE_DELETE; + HANDLE hDir; + + hDir = CreateFileA(path, + desired_access, share_mode, NULL, OPEN_EXISTING, + FILE_FLAG_BACKUP_SEMANTICS | FILE_FLAG_OVERLAPPED, + NULL); + if (hDir == INVALID_HANDLE_VALUE) { + error(_("[GLE %ld] could not watch '%s'"), + GetLastError(), path); + return NULL; + } + + watch = xcalloc(1, sizeof(*watch)); + + watch->buf_len = sizeof(watch->buffer); /* assume full MAX_RDCW_BUF */ + + strbuf_init(&watch->path, 0); + strbuf_addstr(&watch->path, path); + + watch->hDir = hDir; + watch->hEvent = CreateEvent(NULL, TRUE, FALSE, NULL); + + return watch; +} + +static void destroy_watch(struct one_watch *watch) +{ + if (!watch) + return; + + strbuf_release(&watch->path); + if (watch->hDir != INVALID_HANDLE_VALUE) + CloseHandle(watch->hDir); + if (watch->hEvent != INVALID_HANDLE_VALUE) + CloseHandle(watch->hEvent); + + free(watch); +} + +static int start_rdcw_watch(struct fsmonitor_daemon_backend_data *data, + struct one_watch *watch) +{ + DWORD dwNotifyFilter = + FILE_NOTIFY_CHANGE_FILE_NAME | + FILE_NOTIFY_CHANGE_DIR_NAME | + FILE_NOTIFY_CHANGE_ATTRIBUTES | + FILE_NOTIFY_CHANGE_SIZE | + FILE_NOTIFY_CHANGE_LAST_WRITE | + FILE_NOTIFY_CHANGE_CREATION; + + ResetEvent(watch->hEvent); + + memset(&watch->overlapped, 0, sizeof(watch->overlapped)); + watch->overlapped.hEvent = watch->hEvent; + +start_watch: + watch->is_active = ReadDirectoryChangesW( + watch->hDir, watch->buffer, watch->buf_len, TRUE, + dwNotifyFilter, &watch->count, &watch->overlapped, NULL); + + if (!watch->is_active && + GetLastError() == ERROR_INVALID_PARAMETER && + watch->buf_len > MAX_RDCW_BUF_FALLBACK) { + watch->buf_len = MAX_RDCW_BUF_FALLBACK; + goto start_watch; + } + + if (watch->is_active) + return 0; + + error("ReadDirectoryChangedW failed on '%s' [GLE %ld]", + watch->path.buf, GetLastError()); + return -1; +} + +static int recv_rdcw_watch(struct one_watch *watch) +{ + watch->is_active = FALSE; + + if (GetOverlappedResult(watch->hDir, &watch->overlapped, &watch->count, + TRUE)) + return 0; + + // TODO If an external is deleted, the above returns an error. + // TODO I'm not sure that there's anything that we can do here other + // TODO than failing -- the /.git link file would be broken + // TODO anyway. We might try to check for that and return a better + // TODO error message. + + error("GetOverlappedResult failed on '%s' [GLE %ld]", + watch->path.buf, GetLastError()); + return -1; +} + +static void cancel_rdcw_watch(struct one_watch *watch) +{ + DWORD count; + + if (!watch || !watch->is_active) + return; + + CancelIoEx(watch->hDir, &watch->overlapped); + GetOverlappedResult(watch->hDir, &watch->overlapped, &count, TRUE); + watch->is_active = FALSE; +} + +/* + * Process filesystem events that happen anywhere (recursively) under the + * root directory. For a normal working directory, this includes + * both version controlled files and the contents of the .git/ directory. + * + * If /.git is a file, then we only see events for the file + * itself. + */ +static int process_worktree_events(struct fsmonitor_daemon_state *state) +{ + struct fsmonitor_daemon_backend_data *data = state->backend_data; + struct one_watch *watch = data->watch_worktree; + struct strbuf path = STRBUF_INIT; + struct string_list cookie_list = STRING_LIST_INIT_DUP; + struct fsmonitor_batch *batch = NULL; + const char *p = watch->buffer; + + /* + * If the kernel gets more events than will fit in the kernel + * buffer associated with our RDCW handle, it drops them and + * returns a count of zero. (A successful call, but with + * length zero.) + */ + if (!watch->count) { + trace2_data_string("fsmonitor", NULL, "fsm-listen/kernel", + "overflow"); + fsmonitor_force_resync(state); + return LISTENER_HAVE_DATA_WORKTREE; + } + + /* + * On Windows, `info` contains an "array" of paths that are + * relative to the root of whichever directory handle received + * the event. + */ + for (;;) { + FILE_NOTIFY_INFORMATION *info = (void *)p; + const char *slash; + enum fsmonitor_path_type t; + + strbuf_reset(&path); + if (normalize_path_in_utf8(info, &path) == -1) + goto skip_this_path; + + t = fsmonitor_classify_path_workdir_relative(path.buf); + + switch (t) { + case IS_INSIDE_DOT_GIT_WITH_COOKIE_PREFIX: + /* special case cookie files within .git */ + + /* Use just the filename of the cookie file. */ + slash = find_last_dir_sep(path.buf); + string_list_append(&cookie_list, + slash ? slash + 1 : path.buf); + break; + + case IS_INSIDE_DOT_GIT: + /* ignore everything inside of "/.git/" */ + break; + + case IS_DOT_GIT: + /* "/.git" was deleted (or renamed away) */ + if ((info->Action == FILE_ACTION_REMOVED) || + (info->Action == FILE_ACTION_RENAMED_OLD_NAME)) { + trace2_data_string("fsmonitor", NULL, + "fsm-listen/dotgit", + "removed"); + goto force_shutdown; + } + break; + + case IS_WORKDIR_PATH: + /* queue normal pathname */ + if (!batch) + batch = fsmonitor_batch__new(); + fsmonitor_batch__add_path(batch, path.buf); + break; + + case IS_GITDIR: + case IS_INSIDE_GITDIR: + case IS_INSIDE_GITDIR_WITH_COOKIE_PREFIX: + default: + BUG("unexpected path classification '%d' for '%s'", + t, path.buf); + goto skip_this_path; + } + +skip_this_path: + if (!info->NextEntryOffset) + break; + p += info->NextEntryOffset; + } + + fsmonitor_publish(state, batch, &cookie_list); + batch = NULL; + string_list_clear(&cookie_list, 0); + strbuf_release(&path); + return LISTENER_HAVE_DATA_WORKTREE; + +force_shutdown: + fsmonitor_batch__free(batch); + string_list_clear(&cookie_list, 0); + strbuf_release(&path); + return LISTENER_SHUTDOWN; +} + +/* + * Process filesystem events that happend anywhere (recursively) under the + * external (such as non-primary worktrees or submodules). + * We only care about cookie files that our client threads created here. + * + * Note that we DO NOT get filesystem events on the external + * itself (it is not inside something that we are watching). In particular, + * we do not get an event if the external is deleted. + */ +static int process_gitdir_events(struct fsmonitor_daemon_state *state) +{ + struct fsmonitor_daemon_backend_data *data = state->backend_data; + struct one_watch *watch = data->watch_gitdir; + struct strbuf path = STRBUF_INIT; + struct string_list cookie_list = STRING_LIST_INIT_DUP; + const char *p = watch->buffer; + + if (!watch->count) { + trace2_data_string("fsmonitor", NULL, "fsm-listen/kernel", + "overflow"); + fsmonitor_force_resync(state); + return LISTENER_HAVE_DATA_GITDIR; + } + + for (;;) { + FILE_NOTIFY_INFORMATION *info = (void *)p; + const char *slash; + enum fsmonitor_path_type t; + + strbuf_reset(&path); + if (normalize_path_in_utf8(info, &path) == -1) + goto skip_this_path; + + t = fsmonitor_classify_path_gitdir_relative(path.buf); + + trace_printf_key(&trace_fsmonitor, "BBB: %s", path.buf); + + switch (t) { + case IS_INSIDE_GITDIR_WITH_COOKIE_PREFIX: + /* special case cookie files within gitdir */ + + /* Use just the filename of the cookie file. */ + slash = find_last_dir_sep(path.buf); + string_list_append(&cookie_list, + slash ? slash + 1 : path.buf); + break; + + case IS_INSIDE_GITDIR: + goto skip_this_path; + + default: + BUG("unexpected path classification '%d' for '%s'", + t, path.buf); + goto skip_this_path; + } + +skip_this_path: + if (!info->NextEntryOffset) + break; + p += info->NextEntryOffset; + } + + fsmonitor_publish(state, NULL, &cookie_list); + string_list_clear(&cookie_list, 0); + strbuf_release(&path); + return LISTENER_HAVE_DATA_GITDIR; } void fsmonitor_fs_listen__loop(struct fsmonitor_daemon_state *state) { + struct fsmonitor_daemon_backend_data *data = state->backend_data; + DWORD dwWait; + + state->error_code = 0; + + if (start_rdcw_watch(data, data->watch_worktree) == -1) + goto force_error_stop; + + if (data->watch_gitdir && + start_rdcw_watch(data, data->watch_gitdir) == -1) + goto force_error_stop; + + for (;;) { + dwWait = WaitForMultipleObjects(data->nr_listener_handles, + data->hListener, + FALSE, INFINITE); + + if (dwWait == WAIT_OBJECT_0 + LISTENER_HAVE_DATA_WORKTREE) { + if (recv_rdcw_watch(data->watch_worktree) == -1) + goto force_error_stop; + if (process_worktree_events(state) == LISTENER_SHUTDOWN) + goto force_shutdown; + if (start_rdcw_watch(data, data->watch_worktree) == -1) + goto force_error_stop; + continue; + } + + if (dwWait == WAIT_OBJECT_0 + LISTENER_HAVE_DATA_GITDIR) { + if (recv_rdcw_watch(data->watch_gitdir) == -1) + goto force_error_stop; + if (process_gitdir_events(state) == LISTENER_SHUTDOWN) + goto force_shutdown; + if (start_rdcw_watch(data, data->watch_gitdir) == -1) + goto force_error_stop; + continue; + } + + if (dwWait == WAIT_OBJECT_0 + LISTENER_SHUTDOWN) + goto clean_shutdown; + + error(_("could not read directory changes [GLE %ld]"), + GetLastError()); + goto force_error_stop; + } + +force_error_stop: + state->error_code = -1; + +force_shutdown: + /* + * Tell the IPC thead pool to stop (which completes the await + * in the main thread (which will also signal this thread (if + * we are still alive))). + */ + ipc_server_stop_async(state->ipc_server_data); + +clean_shutdown: + cancel_rdcw_watch(data->watch_worktree); + cancel_rdcw_watch(data->watch_gitdir); } int fsmonitor_fs_listen__ctor(struct fsmonitor_daemon_state *state) { + struct fsmonitor_daemon_backend_data *data; + + data = xcalloc(1, sizeof(*data)); + + data->hEventShutdown = CreateEvent(NULL, TRUE, FALSE, NULL); + + data->watch_worktree = create_watch(state, + state->path_worktree_watch.buf); + if (!data->watch_worktree) + goto failed; + + if (state->nr_paths_watching > 1) { + data->watch_gitdir = create_watch(state, + state->path_gitdir_watch.buf); + if (!data->watch_gitdir) + goto failed; + } + + data->hListener[LISTENER_SHUTDOWN] = data->hEventShutdown; + data->nr_listener_handles++; + + data->hListener[LISTENER_HAVE_DATA_WORKTREE] = + data->watch_worktree->hEvent; + data->nr_listener_handles++; + + if (data->watch_gitdir) { + data->hListener[LISTENER_HAVE_DATA_GITDIR] = + data->watch_gitdir->hEvent; + data->nr_listener_handles++; + } + + state->backend_data = data; + return 0; + +failed: + CloseHandle(data->hEventShutdown); + destroy_watch(data->watch_worktree); + destroy_watch(data->watch_gitdir); + return -1; } void fsmonitor_fs_listen__dtor(struct fsmonitor_daemon_state *state) { + struct fsmonitor_daemon_backend_data *data; + + if (!state || !state->backend_data) + return; + + data = state->backend_data; + + CloseHandle(data->hEventShutdown); + destroy_watch(data->watch_worktree); + destroy_watch(data->watch_gitdir); + + FREE_AND_NULL(state->backend_data); } From 6f6589e5bb4698de660efc31cc6a5bfb52264bc0 Mon Sep 17 00:00:00 2001 From: Jeff Hostetler Date: Fri, 18 Dec 2020 11:09:58 -0500 Subject: [PATCH 14/25] fsmonitor-fs-listen-macos: add macos header files for FSEvent Include MacOS system declarations to allow us to use FSEvent and CoreFoundation APIs. We need GCC and clang versions because of compiler and header file conflicts. While it is quite possible to #include Apple's CoreServices.h when compiling C source code with clang, trying to build it with GCC currently fails with this error: In file included from /Library/Developer/CommandLineTools/SDKs/MacOSX10.14.sdk/System/Library/Frameworks/Security.framework/Headers/AuthSession.h:32, from /Library/Developer/CommandLineTools/SDKs/MacOSX10.14.sdk/System/Library/Frameworks/Security.framework/Headers/Security.h:42, from /Library/Developer/CommandLineTools/SDKs/MacOSX10.14.sdk/System/Library/Frameworks/CoreServices.framework/Frameworks/OSServices.framework/Headers/CSIdentity.h:43, from /Library/Developer/CommandLineTools/SDKs/MacOSX10.14.sdk/System/Library/Frameworks/CoreServices.framework/Frameworks/OSServices.framework/Headers/OSServices.h:29, from /Library/Developer/CommandLineTools/SDKs/MacOSX10.14.sdk/System/Library/Frameworks/CoreServices.framework/Frameworks/LaunchServices.framework/Headers/IconsCore.h:23, from /Library/Developer/CommandLineTools/SDKs/MacOSX10.14.sdk/System/Library/Frameworks/CoreServices.framework/Frameworks/LaunchServices.framework/Headers/LaunchServices.h:23, from /Library/Developer/CommandLineTools/SDKs/MacOSX10.14.sdk/System/Library/Frameworks/CoreServices.framework/Headers/CoreServices.h:45, /Library/Developer/CommandLineTools/SDKs/MacOSX10.14.sdk/System/Library/Frameworks/Security.framework/Headers/Authorization.h:193:7: error: variably modified 'bytes' at file scope 193 | char bytes[kAuthorizationExternalFormLength]; | ^~~~~ The underlying reason is that GCC (rightfully) objects that an `enum` value such as `kAuthorizationExternalFormLength` is not a constant (because it is not, the preprocessor has no knowledge of it, only the actual C compiler does) and can therefore not be used to define the size of a C array. This is a known problem and tracked in GCC's bug tracker: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93082 In the meantime, let's not block things and go the slightly ugly route of declaring/defining the FSEvents constants, data structures and functions that we need, so that we can avoid above-mentioned issue. Let's do this _only_ for GCC, though, so that the CI/PR builds (which build both with clang and with GCC) can guarantee that we _are_ using the correct data types. Signed-off-by: Johannes Schindelin Signed-off-by: Jeff Hostetler --- compat/fsmonitor/fsmonitor-fs-listen-macos.c | 96 ++++++++++++++++++++ 1 file changed, 96 insertions(+) diff --git a/compat/fsmonitor/fsmonitor-fs-listen-macos.c b/compat/fsmonitor/fsmonitor-fs-listen-macos.c index b91058d1c4f820..bec5130d9e1d8a 100644 --- a/compat/fsmonitor/fsmonitor-fs-listen-macos.c +++ b/compat/fsmonitor/fsmonitor-fs-listen-macos.c @@ -1,3 +1,99 @@ +#if defined(__GNUC__) +/* + * It is possible to #include CoreFoundation/CoreFoundation.h when compiling + * with clang, but not with GCC as of time of writing. + * + * See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93082 for details. + */ +typedef unsigned int FSEventStreamCreateFlags; +#define kFSEventStreamEventFlagNone 0x00000000 +#define kFSEventStreamEventFlagMustScanSubDirs 0x00000001 +#define kFSEventStreamEventFlagUserDropped 0x00000002 +#define kFSEventStreamEventFlagKernelDropped 0x00000004 +#define kFSEventStreamEventFlagEventIdsWrapped 0x00000008 +#define kFSEventStreamEventFlagHistoryDone 0x00000010 +#define kFSEventStreamEventFlagRootChanged 0x00000020 +#define kFSEventStreamEventFlagMount 0x00000040 +#define kFSEventStreamEventFlagUnmount 0x00000080 +#define kFSEventStreamEventFlagItemCreated 0x00000100 +#define kFSEventStreamEventFlagItemRemoved 0x00000200 +#define kFSEventStreamEventFlagItemInodeMetaMod 0x00000400 +#define kFSEventStreamEventFlagItemRenamed 0x00000800 +#define kFSEventStreamEventFlagItemModified 0x00001000 +#define kFSEventStreamEventFlagItemFinderInfoMod 0x00002000 +#define kFSEventStreamEventFlagItemChangeOwner 0x00004000 +#define kFSEventStreamEventFlagItemXattrMod 0x00008000 +#define kFSEventStreamEventFlagItemIsFile 0x00010000 +#define kFSEventStreamEventFlagItemIsDir 0x00020000 +#define kFSEventStreamEventFlagItemIsSymlink 0x00040000 +#define kFSEventStreamEventFlagOwnEvent 0x00080000 +#define kFSEventStreamEventFlagItemIsHardlink 0x00100000 +#define kFSEventStreamEventFlagItemIsLastHardlink 0x00200000 +#define kFSEventStreamEventFlagItemCloned 0x00400000 + +typedef struct __FSEventStream *FSEventStreamRef; +typedef const FSEventStreamRef ConstFSEventStreamRef; + +typedef unsigned int CFStringEncoding; +#define kCFStringEncodingUTF8 0x08000100 + +typedef const struct __CFString *CFStringRef; +typedef const struct __CFArray *CFArrayRef; +typedef const struct __CFRunLoop *CFRunLoopRef; + +struct FSEventStreamContext { + long long version; + void *cb_data, *retain, *release, *copy_description; +}; + +typedef struct FSEventStreamContext FSEventStreamContext; +typedef unsigned int FSEventStreamEventFlags; +#define kFSEventStreamCreateFlagNoDefer 0x02 +#define kFSEventStreamCreateFlagWatchRoot 0x04 +#define kFSEventStreamCreateFlagFileEvents 0x10 + +typedef unsigned long long FSEventStreamEventId; +#define kFSEventStreamEventIdSinceNow 0xFFFFFFFFFFFFFFFFULL + +typedef void (*FSEventStreamCallback)(ConstFSEventStreamRef streamRef, + void *context, + __SIZE_TYPE__ num_of_events, + void *event_paths, + const FSEventStreamEventFlags event_flags[], + const FSEventStreamEventId event_ids[]); +typedef double CFTimeInterval; +FSEventStreamRef FSEventStreamCreate(void *allocator, + FSEventStreamCallback callback, + FSEventStreamContext *context, + CFArrayRef paths_to_watch, + FSEventStreamEventId since_when, + CFTimeInterval latency, + FSEventStreamCreateFlags flags); +CFStringRef CFStringCreateWithCString(void *allocator, const char *string, + CFStringEncoding encoding); +CFArrayRef CFArrayCreate(void *allocator, const void **items, long long count, + void *callbacks); +void CFRunLoopRun(void); +void CFRunLoopStop(CFRunLoopRef run_loop); +CFRunLoopRef CFRunLoopGetCurrent(void); +extern CFStringRef kCFRunLoopDefaultMode; +void FSEventStreamScheduleWithRunLoop(FSEventStreamRef stream, + CFRunLoopRef run_loop, + CFStringRef run_loop_mode); +unsigned char FSEventStreamStart(FSEventStreamRef stream); +void FSEventStreamStop(FSEventStreamRef stream); +void FSEventStreamInvalidate(FSEventStreamRef stream); +void FSEventStreamRelease(FSEventStreamRef stream); +#else +/* + * Let Apple's headers declare `isalnum()` first, before + * Git's headers override it via a constant + */ +#include +#include +#include +#endif + #include "cache.h" #include "fsmonitor.h" #include "fsmonitor-fs-listen.h" From ba2fdc183c492faa0208a13b90303adad0d03230 Mon Sep 17 00:00:00 2001 From: Jeff Hostetler Date: Fri, 18 Dec 2020 11:22:25 -0500 Subject: [PATCH 15/25] fsmonitor-fs-listen-macos: implement FSEvent listener on MacOS Implement file system event listener on MacOS using FSEvent, CoreFoundation, and CoreServices. Co-authored-by: Kevin Willford Co-authored-by: Johannes Schindelin Signed-off-by: Jeff Hostetler --- compat/fsmonitor/fsmonitor-fs-listen-macos.c | 368 +++++++++++++++++++ 1 file changed, 368 insertions(+) diff --git a/compat/fsmonitor/fsmonitor-fs-listen-macos.c b/compat/fsmonitor/fsmonitor-fs-listen-macos.c index bec5130d9e1d8a..e055fb579cc49a 100644 --- a/compat/fsmonitor/fsmonitor-fs-listen-macos.c +++ b/compat/fsmonitor/fsmonitor-fs-listen-macos.c @@ -97,20 +97,388 @@ void FSEventStreamRelease(FSEventStreamRef stream); #include "cache.h" #include "fsmonitor.h" #include "fsmonitor-fs-listen.h" +#include "fsmonitor--daemon.h" + +struct fsmonitor_daemon_backend_data +{ + CFStringRef cfsr_worktree_path; + CFStringRef cfsr_gitdir_path; + + CFArrayRef cfar_paths_to_watch; + int nr_paths_watching; + + FSEventStreamRef stream; + + CFRunLoopRef rl; + + enum shutdown_style { + SHUTDOWN_EVENT = 0, + FORCE_SHUTDOWN, + FORCE_ERROR_STOP, + } shutdown_style; + + unsigned int stream_scheduled:1; + unsigned int stream_started:1; +}; + +static void log_flags_set(const char *path, const FSEventStreamEventFlags flag) +{ + struct strbuf msg = STRBUF_INIT; + + if (flag & kFSEventStreamEventFlagMustScanSubDirs) + strbuf_addstr(&msg, "MustScanSubDirs|"); + if (flag & kFSEventStreamEventFlagUserDropped) + strbuf_addstr(&msg, "UserDropped|"); + if (flag & kFSEventStreamEventFlagKernelDropped) + strbuf_addstr(&msg, "KernelDropped|"); + if (flag & kFSEventStreamEventFlagEventIdsWrapped) + strbuf_addstr(&msg, "EventIdsWrapped|"); + if (flag & kFSEventStreamEventFlagHistoryDone) + strbuf_addstr(&msg, "HistoryDone|"); + if (flag & kFSEventStreamEventFlagRootChanged) + strbuf_addstr(&msg, "RootChanged|"); + if (flag & kFSEventStreamEventFlagMount) + strbuf_addstr(&msg, "Mount|"); + if (flag & kFSEventStreamEventFlagUnmount) + strbuf_addstr(&msg, "Unmount|"); + if (flag & kFSEventStreamEventFlagItemChangeOwner) + strbuf_addstr(&msg, "ItemChangeOwner|"); + if (flag & kFSEventStreamEventFlagItemCreated) + strbuf_addstr(&msg, "ItemCreated|"); + if (flag & kFSEventStreamEventFlagItemFinderInfoMod) + strbuf_addstr(&msg, "ItemFinderInfoMod|"); + if (flag & kFSEventStreamEventFlagItemInodeMetaMod) + strbuf_addstr(&msg, "ItemInodeMetaMod|"); + if (flag & kFSEventStreamEventFlagItemIsDir) + strbuf_addstr(&msg, "ItemIsDir|"); + if (flag & kFSEventStreamEventFlagItemIsFile) + strbuf_addstr(&msg, "ItemIsFile|"); + if (flag & kFSEventStreamEventFlagItemIsHardlink) + strbuf_addstr(&msg, "ItemIsHardlink|"); + if (flag & kFSEventStreamEventFlagItemIsLastHardlink) + strbuf_addstr(&msg, "ItemIsLastHardlink|"); + if (flag & kFSEventStreamEventFlagItemIsSymlink) + strbuf_addstr(&msg, "ItemIsSymlink|"); + if (flag & kFSEventStreamEventFlagItemModified) + strbuf_addstr(&msg, "ItemModified|"); + if (flag & kFSEventStreamEventFlagItemRemoved) + strbuf_addstr(&msg, "ItemRemoved|"); + if (flag & kFSEventStreamEventFlagItemRenamed) + strbuf_addstr(&msg, "ItemRenamed|"); + if (flag & kFSEventStreamEventFlagItemXattrMod) + strbuf_addstr(&msg, "ItemXattrMod|"); + if (flag & kFSEventStreamEventFlagOwnEvent) + strbuf_addstr(&msg, "OwnEvent|"); + if (flag & kFSEventStreamEventFlagItemCloned) + strbuf_addstr(&msg, "ItemCloned|"); + + trace_printf_key(&trace_fsmonitor, "fsevent: '%s', flags=%u %s", + path, flag, msg.buf); + + strbuf_release(&msg); +} + +static int ef_is_root_delete(const FSEventStreamEventFlags ef) +{ + return (ef & kFSEventStreamEventFlagItemIsDir && + ef & kFSEventStreamEventFlagItemRemoved); +} + +static int ef_is_root_renamed(const FSEventStreamEventFlags ef) +{ + return (ef & kFSEventStreamEventFlagItemIsDir && + ef & kFSEventStreamEventFlagItemRenamed); +} + +static void fsevent_callback(ConstFSEventStreamRef streamRef, + void *ctx, + size_t num_of_events, + void *event_paths, + const FSEventStreamEventFlags event_flags[], + const FSEventStreamEventId event_ids[]) +{ + struct fsmonitor_daemon_state *state = ctx; + struct fsmonitor_daemon_backend_data *data = state->backend_data; + char **paths = (char **)event_paths; + struct fsmonitor_batch *batch = NULL; + struct string_list cookie_list = STRING_LIST_INIT_DUP; + const char *path_k; + const char *slash; + int k; + + /* + * Build a list of all filesystem changes into a private/local + * list and without holding any locks. + */ + for (k = 0; k < num_of_events; k++) { + /* + * On Mac, we receive an array of absolute paths. + */ + path_k = paths[k]; + + /* + * If you want to debug FSEvents, log them to GIT_TRACE_FSMONITOR. + * Please don't log them to Trace2. + * + * trace_printf_key(&trace_fsmonitor, "XXX '%s'", path_k); + */ + + /* + * If event[k] is marked as dropped, we assume that we have + * lost sync with the filesystem and should flush our cached + * data. We need to: + * + * [1] Abort/wake any client threads waiting for a cookie and + * flush the cached state data (the current token), and + * create a new token. + * + * [2] Discard the batch that we were locally building (since + * they are conceptually relative to the just flushed + * token). + */ + if ((event_flags[k] & kFSEventStreamEventFlagKernelDropped) || + (event_flags[k] & kFSEventStreamEventFlagUserDropped)) { + /* + * see also kFSEventStreamEventFlagMustScanSubDirs + */ + trace2_data_string("fsmonitor", NULL, + "fsm-listen/kernel", "dropped"); + + fsmonitor_force_resync(state); + + if (fsmonitor_batch__free(batch)) + BUG("batch should not have a next"); + string_list_clear(&cookie_list, 0); + + /* + * We assume that any events that we received + * in this callback after this dropped event + * may still be valid, so we continue rather + * than break. (And just in case there is a + * delete of ".git" hiding in there.) + */ + continue; + } + + switch (fsmonitor_classify_path_absolute(state, path_k)) { + + case IS_INSIDE_DOT_GIT_WITH_COOKIE_PREFIX: + case IS_INSIDE_GITDIR_WITH_COOKIE_PREFIX: + /* special case cookie files within .git or gitdir */ + + /* Use just the filename of the cookie file. */ + slash = find_last_dir_sep(path_k); + string_list_append(&cookie_list, + slash ? slash + 1 : path_k); + break; + + case IS_INSIDE_DOT_GIT: + case IS_INSIDE_GITDIR: + /* ignore all other paths inside of .git or gitdir */ + break; + + case IS_DOT_GIT: + case IS_GITDIR: + /* + * If .git directory is deleted or renamed away, + * we have to quit. + */ + if (ef_is_root_delete(event_flags[k])) { + trace2_data_string("fsmonitor", NULL, + "fsm-listen/gitdir", + "removed"); + goto force_shutdown; + } + if (ef_is_root_renamed(event_flags[k])) { + trace2_data_string("fsmonitor", NULL, + "fsm-listen/gitdir", + "renamed"); + goto force_shutdown; + } + break; + + case IS_WORKDIR_PATH: + /* try to queue normal pathnames */ + + if (trace_pass_fl(&trace_fsmonitor)) + log_flags_set(path_k, event_flags[k]); + + /* fsevent could be marked as both a file and directory */ + + if (event_flags[k] & kFSEventStreamEventFlagItemIsFile) { + const char *rel = path_k + + state->path_worktree_watch.len + 1; + + if (!batch) + batch = fsmonitor_batch__new(); + fsmonitor_batch__add_path(batch, rel); + } + + if (event_flags[k] & kFSEventStreamEventFlagItemIsDir) { + const char *rel = path_k + + state->path_worktree_watch.len + 1; + char *p = xstrfmt("%s/", rel); + + if (!batch) + batch = fsmonitor_batch__new(); + fsmonitor_batch__add_path(batch, p); + + free(p); + } + + break; + + case IS_OUTSIDE_CONE: + default: + trace_printf_key(&trace_fsmonitor, + "ignoring '%s'", path_k); + break; + } + } + + fsmonitor_publish(state, batch, &cookie_list); + string_list_clear(&cookie_list, 0); + return; + +force_shutdown: + if (fsmonitor_batch__free(batch)) + BUG("batch should not have a next"); + string_list_clear(&cookie_list, 0); + + data->shutdown_style = FORCE_SHUTDOWN; + CFRunLoopStop(data->rl); + return; +} + +/* + * TODO Investigate the proper value for the `latency` argument in the call + * TODO to `FSEventStreamCreate()`. I'm not sure that this needs to be a + * TODO config setting or just something that we tune after some testing. + * TODO + * TODO With a latency of 0.1, I was seeing lots of dropped events during + * TODO the "touch 100000" files test within t/perf/p7519, but with a + * TODO latency of 0.001 I did not see any dropped events. So the "correct" + * TODO value may be somewhere in between. + * TODO + * TODO https://developer.apple.com/documentation/coreservices/1443980-fseventstreamcreate + */ int fsmonitor_fs_listen__ctor(struct fsmonitor_daemon_state *state) { + FSEventStreamCreateFlags flags = kFSEventStreamCreateFlagNoDefer | + kFSEventStreamCreateFlagWatchRoot | + kFSEventStreamCreateFlagFileEvents; + FSEventStreamContext ctx = { + 0, + state, + NULL, + NULL, + NULL + }; + struct fsmonitor_daemon_backend_data *data; + const void *dir_array[2]; + + data = xcalloc(1, sizeof(*data)); + state->backend_data = data; + + data->cfsr_worktree_path = CFStringCreateWithCString( + NULL, state->path_worktree_watch.buf, kCFStringEncodingUTF8); + dir_array[data->nr_paths_watching++] = data->cfsr_worktree_path; + + if (state->nr_paths_watching > 1) { + data->cfsr_gitdir_path = CFStringCreateWithCString( + NULL, state->path_gitdir_watch.buf, + kCFStringEncodingUTF8); + dir_array[data->nr_paths_watching++] = data->cfsr_gitdir_path; + } + + data->cfar_paths_to_watch = CFArrayCreate(NULL, dir_array, + data->nr_paths_watching, + NULL); + data->stream = FSEventStreamCreate(NULL, fsevent_callback, &ctx, + data->cfar_paths_to_watch, + kFSEventStreamEventIdSinceNow, + 0.001, flags); + if (data->stream == NULL) + goto failed; + + /* + * `data->rl` needs to be set inside the listener thread. + */ + + return 0; + +failed: + error("Unable to create FSEventStream."); + + FREE_AND_NULL(state->backend_data); return -1; } void fsmonitor_fs_listen__dtor(struct fsmonitor_daemon_state *state) { + struct fsmonitor_daemon_backend_data *data; + + if (!state || !state->backend_data) + return; + + data = state->backend_data; + + if (data->stream) { + if (data->stream_started) + FSEventStreamStop(data->stream); + if (data->stream_scheduled) + FSEventStreamInvalidate(data->stream); + FSEventStreamRelease(data->stream); + } + + FREE_AND_NULL(state->backend_data); } void fsmonitor_fs_listen__stop_async(struct fsmonitor_daemon_state *state) { + struct fsmonitor_daemon_backend_data *data; + + data = state->backend_data; + data->shutdown_style = SHUTDOWN_EVENT; + + CFRunLoopStop(data->rl); } void fsmonitor_fs_listen__loop(struct fsmonitor_daemon_state *state) { + struct fsmonitor_daemon_backend_data *data; + + data = state->backend_data; + + data->rl = CFRunLoopGetCurrent(); + + FSEventStreamScheduleWithRunLoop(data->stream, data->rl, kCFRunLoopDefaultMode); + data->stream_scheduled = 1; + + if (!FSEventStreamStart(data->stream)) { + error("Failed to start the FSEventStream"); + goto force_error_stop_without_loop; + } + data->stream_started = 1; + + CFRunLoopRun(); + + switch (data->shutdown_style) { + case FORCE_ERROR_STOP: + state->error_code = -1; + /* fall thru */ + case FORCE_SHUTDOWN: + ipc_server_stop_async(state->ipc_server_data); + /* fall thru */ + case SHUTDOWN_EVENT: + default: + break; + } + return; + +force_error_stop_without_loop: + state->error_code = -1; + ipc_server_stop_async(state->ipc_server_data); + return; } From e783c5993c4bf6de345e0775fec5eccd400adfc8 Mon Sep 17 00:00:00 2001 From: Jeff Hostetler Date: Fri, 18 Dec 2020 11:43:16 -0500 Subject: [PATCH 16/25] 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 --- builtin/fsmonitor--daemon.c | 335 +++++++++++++++++++++++++++++++++++- 1 file changed, 333 insertions(+), 2 deletions(-) diff --git a/builtin/fsmonitor--daemon.c b/builtin/fsmonitor--daemon.c index 48071d445c4922..32df392b25d35d 100644 --- a/builtin/fsmonitor--daemon.c +++ b/builtin/fsmonitor--daemon.c @@ -7,6 +7,7 @@ #include "fsmonitor--daemon.h" #include "simple-ipc.h" #include "khash.h" +#include "pkt-line.h" static const char * const builtin_fsmonitor__daemon_usage[] = { N_("git fsmonitor--daemon --start []"), @@ -369,19 +370,349 @@ void fsmonitor_force_resync(struct fsmonitor_daemon_state *state) fsmonitor_free_token_data(free_me); } +/* + * Format an opaque token string to send to the client. + */ +static void fsmonitor_format_response_token( + struct strbuf *response_token, + const struct strbuf *response_token_id, + const struct fsmonitor_batch *batch) +{ + uint64_t seq_nr = (batch) ? batch->batch_seq_nr + 1 : 0; + + strbuf_reset(response_token); + strbuf_addf(response_token, "builtin:%s:%"PRIu64, + response_token_id->buf, seq_nr); +} + +/* + * Parse an opaque token from the client. + */ +static int fsmonitor_parse_client_token(const char *buf_token, + struct strbuf *requested_token_id, + uint64_t *seq_nr) +{ + const char *p; + char *p_end; + + strbuf_reset(requested_token_id); + *seq_nr = 0; + + if (!skip_prefix(buf_token, "builtin:", &p)) + return 1; + + while (*p && *p != ':') + strbuf_addch(requested_token_id, *p++); + if (!*p++) + return 1; + + *seq_nr = (uint64_t)strtoumax(p, &p_end, 10); + if (*p_end) + return 1; + + return 0; +} + +KHASH_INIT(str, const char *, int, 0, kh_str_hash_func, kh_str_hash_equal); + +static int do_handle_client(struct fsmonitor_daemon_state *state, + const char *command, + ipc_server_reply_cb *reply, + struct ipc_server_reply_data *reply_data) +{ + struct fsmonitor_token_data *token_data = NULL; + struct strbuf response_token = STRBUF_INIT; + struct strbuf requested_token_id = STRBUF_INIT; + struct strbuf payload = STRBUF_INIT; + uint64_t requested_oldest_seq_nr = 0; + uint64_t total_response_len = 0; + const char *p; + const struct fsmonitor_batch *batch_head; + const struct fsmonitor_batch *batch; + intmax_t count = 0, duplicates = 0; + kh_str_t *shown; + int hash_ret; + int result; + + /* + * We expect `command` to be of the form: + * + * := quit NUL + * | flush NUL + * | NUL + * | NUL + */ + + if (!strcmp(command, "quit")) { + /* + * A client has requested over the socket/pipe that the + * daemon shutdown. + * + * Tell the IPC thread pool to shutdown (which completes + * the await in the main thread (which can stop the + * fsmonitor listener thread)). + * + * There is no reply to the client. + */ + return SIMPLE_IPC_QUIT; + } + + if (!strcmp(command, "flush")) { + /* + * Flush all of our cached data and generate a new token + * just like if we lost sync with the filesystem. + * + * Then send a trivial response using the new token. + */ + fsmonitor_force_resync(state); + result = 0; + goto send_trivial_response; + } + + if (!skip_prefix(command, "builtin:", &p)) { + /* assume V1 timestamp or garbage */ + + char *p_end; + + strtoumax(command, &p_end, 10); + trace_printf_key(&trace_fsmonitor, + ((*p_end) ? + "fsmonitor: invalid command line '%s'" : + "fsmonitor: unsupported V1 protocol '%s'"), + command); + result = -1; + goto send_trivial_response; + } + + /* try V2 token */ + + if (fsmonitor_parse_client_token(command, &requested_token_id, + &requested_oldest_seq_nr)) { + trace_printf_key(&trace_fsmonitor, + "fsmonitor: invalid V2 protocol token '%s'", + command); + result = -1; + goto send_trivial_response; + } + + pthread_mutex_lock(&state->main_lock); + + if (!state->current_token_data) { + /* + * We don't have a current token. This may mean that + * the listener thread has not yet started. + */ + pthread_mutex_unlock(&state->main_lock); + result = 0; + goto send_trivial_response; + } + if (strcmp(requested_token_id.buf, + state->current_token_data->token_id.buf)) { + /* + * The client last spoke to a different daemon + * instance -OR- the daemon had to resync with + * the filesystem (and lost events), so reject. + */ + pthread_mutex_unlock(&state->main_lock); + result = 0; + trace2_data_string("fsmonitor", the_repository, + "response/token", "different"); + goto send_trivial_response; + } + if (!state->current_token_data->batch_tail) { + /* + * The listener has not received any filesystem + * events yet since we created the current token. + * We can respond with an empty list, since the + * client has already seen the current token and + * we have nothing new to report. (This is + * instead of sending a trivial response.) + */ + pthread_mutex_unlock(&state->main_lock); + result = 0; + goto send_empty_response; + } + if (requested_oldest_seq_nr < + state->current_token_data->batch_tail->batch_seq_nr) { + /* + * The client wants older events than we have for + * this token_id. This means that the end of our + * batch list was truncated and we cannot give the + * client a complete snapshot relative to their + * request. + */ + pthread_mutex_unlock(&state->main_lock); + + trace_printf_key(&trace_fsmonitor, + "client requested truncated data"); + result = 0; + goto send_trivial_response; + } + + /* + * We're going to hold onto a pointer to the current + * token-data while we walk the list of batches of files. + * During this time, we will NOT be under the lock. + * So we ref-count it. + * + * This allows the listener thread to continue prepending + * new batches of items to the token-data (which we'll ignore). + * + * AND it allows the listener thread to do a token-reset + * (and install a new `current_token_data`). + * + * We mark the current head of the batch list as "pinned" so + * that the listener thread will treat this item as read-only + * (and prevent any more paths from being added to it) from + * now on. + */ + token_data = state->current_token_data; + token_data->client_ref_count++; + + batch_head = token_data->batch_head; + ((struct fsmonitor_batch *)batch_head)->pinned_time = time(NULL); + + pthread_mutex_unlock(&state->main_lock); + + /* + * FSMonitor Protocol V2 requires that we send a response header + * with a "new current token" and then all of the paths that changed + * since the "requested token". + */ + fsmonitor_format_response_token(&response_token, + &token_data->token_id, + batch_head); + + reply(reply_data, response_token.buf, response_token.len + 1); + total_response_len += response_token.len + 1; + + trace2_data_string("fsmonitor", the_repository, "response/token", + response_token.buf); + trace_printf_key(&trace_fsmonitor, "response token: %s", response_token.buf); + + shown = kh_init_str(); + for (batch = batch_head; + batch && batch->batch_seq_nr >= requested_oldest_seq_nr; + batch = batch->next) { + size_t k; + + for (k = 0; k < batch->nr; k++) { + const char *s = batch->interned_paths[k]; + size_t s_len; + + if (kh_get_str(shown, s) != kh_end(shown)) + duplicates++; + else { + kh_put_str(shown, s, &hash_ret); + + trace_printf_key(&trace_fsmonitor, + "send[%"PRIuMAX"]: %s", + count, s); + + /* Each path gets written with a trailing NUL */ + s_len = strlen(s) + 1; + + if (payload.len + s_len >= + LARGE_PACKET_DATA_MAX) { + reply(reply_data, payload.buf, + payload.len); + total_response_len += payload.len; + strbuf_reset(&payload); + } + + strbuf_add(&payload, s, s_len); + count++; + } + } + } + + if (payload.len) { + reply(reply_data, payload.buf, payload.len); + total_response_len += payload.len; + } + + kh_release_str(shown); + + pthread_mutex_lock(&state->main_lock); + if (token_data->client_ref_count > 0) + token_data->client_ref_count--; + + if (token_data->client_ref_count == 0) { + if (token_data != state->current_token_data) { + /* + * The listener thread did a token-reset while we were + * walking the batch list. Therefore, this token is + * stale and can be discarded completely. If we are + * the last reader thread using this token, we own + * that work. + */ + fsmonitor_free_token_data(token_data); + } + } + + pthread_mutex_unlock(&state->main_lock); + + trace2_data_intmax("fsmonitor", the_repository, "response/length", total_response_len); + trace2_data_intmax("fsmonitor", the_repository, "response/count/files", count); + trace2_data_intmax("fsmonitor", the_repository, "response/count/duplicates", duplicates); + + strbuf_release(&response_token); + strbuf_release(&requested_token_id); + strbuf_release(&payload); + + return 0; + +send_trivial_response: + pthread_mutex_lock(&state->main_lock); + fsmonitor_format_response_token(&response_token, + &state->current_token_data->token_id, + state->current_token_data->batch_head); + pthread_mutex_unlock(&state->main_lock); + + reply(reply_data, response_token.buf, response_token.len + 1); + trace2_data_string("fsmonitor", the_repository, "response/token", + response_token.buf); + reply(reply_data, "/", 2); + trace2_data_intmax("fsmonitor", the_repository, "response/trivial", 1); + + strbuf_release(&response_token); + strbuf_release(&requested_token_id); + + return result; + +send_empty_response: + pthread_mutex_lock(&state->main_lock); + fsmonitor_format_response_token(&response_token, + &state->current_token_data->token_id, + NULL); + pthread_mutex_unlock(&state->main_lock); + + reply(reply_data, response_token.buf, response_token.len + 1); + trace2_data_string("fsmonitor", the_repository, "response/token", + response_token.buf); + trace2_data_intmax("fsmonitor", the_repository, "response/empty", 1); + + strbuf_release(&response_token); + strbuf_release(&requested_token_id); + + return 0; +} + static ipc_server_application_cb handle_client; static int handle_client(void *data, const char *command, ipc_server_reply_cb *reply, struct ipc_server_reply_data *reply_data) { - /* struct fsmonitor_daemon_state *state = data; */ + struct fsmonitor_daemon_state *state = data; int result; + trace_printf_key(&trace_fsmonitor, "requested token: %s", command); + trace2_region_enter("fsmonitor", "handle_client", the_repository); trace2_data_string("fsmonitor", the_repository, "request", command); - result = 0; /* TODO Do something here. */ + result = do_handle_client(state, command, reply, reply_data); trace2_region_leave("fsmonitor", "handle_client", the_repository); From e72f6dc518d5f57e2040b51c077ce851dcc165df Mon Sep 17 00:00:00 2001 From: Jeff Hostetler Date: Fri, 18 Dec 2020 11:46:06 -0500 Subject: [PATCH 17/25] 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 that 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 --- builtin/fsmonitor--daemon.c | 78 +++++++++++++++++++++++++++++++++++++ 1 file changed, 78 insertions(+) diff --git a/builtin/fsmonitor--daemon.c b/builtin/fsmonitor--daemon.c index 32df392b25d35d..e9a9aea59ad678 100644 --- a/builtin/fsmonitor--daemon.c +++ b/builtin/fsmonitor--daemon.c @@ -316,6 +316,75 @@ static void fsmonitor_batch__combine(struct fsmonitor_batch *batch_dest, batch_src->interned_paths[k]; } +/* + * To keep the batch list from growing unbounded in response to filesystem + * activity, we try to truncate old batches from the end of the list as + * they become irrelevant. + * + * We assume that the .git/index will be updated with the most recent token + * any time the index is updated. And future commands will only ask for + * recent changes *since* that new token. So as tokens advance into the + * future, older batch items will never be requested/needed. So we can + * truncate them without loss of functionality. + * + * However, multiple commands may be talking to the daemon concurrently + * or perform a slow command, so a little "token skew" is possible. + * Therefore, we want this to be a little bit lazy and have a generous + * delay. + * + * The current reader thread walked backwards in time from `token->batch_head` + * back to `batch_marker` somewhere in the middle of the batch list. + * + * Let's walk backwards in time from that marker an arbitrary delay + * and truncate the list there. Note that these timestamps are completely + * artificial (based on when we pinned the batch item) and not on any + * filesystem activity. + */ +#define MY_TIME_DELAY (5 * 60) /* seconds */ + +static void fsmonitor_batch__truncate(struct fsmonitor_daemon_state *state, + const struct fsmonitor_batch *batch_marker) +{ + /* assert state->main_lock */ + + const struct fsmonitor_batch *batch; + struct fsmonitor_batch *rest; + struct fsmonitor_batch *p; + time_t t; + + if (!batch_marker) + return; + + trace_printf_key(&trace_fsmonitor, "TRNC mark (%"PRIu64",%"PRIu64")", + batch_marker->batch_seq_nr, + (uint64_t)batch_marker->pinned_time); + + for (batch = batch_marker; batch; batch = batch->next) { + if (!batch->pinned_time) /* an overflow batch */ + continue; + + t = batch->pinned_time + MY_TIME_DELAY; + if (t > batch_marker->pinned_time) /* too close to marker */ + continue; + + goto truncate_past_here; + } + + return; + +truncate_past_here: + state->current_token_data->batch_tail = (struct fsmonitor_batch *)batch; + + rest = ((struct fsmonitor_batch *)batch)->next; + ((struct fsmonitor_batch *)batch)->next = NULL; + + for (p = rest; p; p = fsmonitor_batch__free(p)) { + trace_printf_key(&trace_fsmonitor, + "TRNC kill (%"PRIu64",%"PRIu64")", + p->batch_seq_nr, (uint64_t)p->pinned_time); + } +} + static void fsmonitor_free_token_data(struct fsmonitor_token_data *token) { struct fsmonitor_batch *p; @@ -647,6 +716,15 @@ static int do_handle_client(struct fsmonitor_daemon_state *state, * that work. */ fsmonitor_free_token_data(token_data); + } else if (batch) { + /* + * This batch is the first item in the list + * that is older than the requested sequence + * number and might be considered to be + * obsolete. See if we can truncate the list + * and save some memory. + */ + fsmonitor_batch__truncate(state, batch); } } From 3872a656c42136533008982b05e3e909abb5b6ff Mon Sep 17 00:00:00 2001 From: Jeff Hostetler Date: Fri, 18 Dec 2020 11:57:05 -0500 Subject: [PATCH 18/25] fsmonitor--daemon:: introduce client delay for testing Define GIT_TEST_FSMONITOR_CLIENT_DELAY as a millisecond delay. Introduce an artificial delay when processing client requests. This make the CI/PR test suite a little more stable and avoids the need to load up test scripts with sleep statements to avoid racy failures. This was mostly seen on 1 or 2 core CI build machines where the test script would create a file and quickly try to confirm that the daemon had seen it *before* the daemon had received the kernel event and causing a test failure. Signed-off-by: Jeff Hostetler --- builtin/fsmonitor--daemon.c | 38 ++++++++++++++++++++++++++++++++++++- 1 file changed, 37 insertions(+), 1 deletion(-) diff --git a/builtin/fsmonitor--daemon.c b/builtin/fsmonitor--daemon.c index e9a9aea59ad678..0cb09ef0b98486 100644 --- a/builtin/fsmonitor--daemon.c +++ b/builtin/fsmonitor--daemon.c @@ -150,6 +150,30 @@ static int do_as_client__send_flush(void) return 0; } +static int lookup_client_test_delay(void) +{ + static int delay_ms = -1; + + const char *s; + int ms; + + if (delay_ms >= 0) + return delay_ms; + + delay_ms = 0; + + s = getenv("GIT_TEST_FSMONITOR_CLIENT_DELAY"); + if (!s) + return delay_ms; + + ms = atoi(s); + if (ms < 0) + return delay_ms; + + delay_ms = ms; + return delay_ms; +} + /* * Requests to and from a FSMonitor Protocol V2 provider use an opaque * "token" as a virtual timestamp. Clients can request a summary of all @@ -526,6 +550,18 @@ static int do_handle_client(struct fsmonitor_daemon_state *state, return SIMPLE_IPC_QUIT; } + /* + * For testing purposes, introduce an artificial delay in this + * worker to allow the filesystem listener thread to receive + * any fs events that may have been generated by the client + * process on the other end of the pipe/socket. This helps + * make the CI/PR test suite runs a little more predictable + * and hopefully eliminates the need to introduce `sleep` + * commands in the test scripts. + */ + if (state->test_client_delay_ms) + sleep_millisec(state->test_client_delay_ms); + if (!strcmp(command, "flush")) { /* * Flush all of our cached data and generate a new token @@ -1038,7 +1074,7 @@ static int fsmonitor_run_daemon(void) pthread_mutex_init(&state.main_lock, NULL); state.error_code = 0; state.current_token_data = fsmonitor_new_token_data(); - state.test_client_delay_ms = 0; + state.test_client_delay_ms = lookup_client_test_delay(); /* Prepare to (recursively) watch the directory. */ strbuf_init(&state.path_worktree_watch, 0); From 9be187334bc5039e49dca752418ec01be90ef4d3 Mon Sep 17 00:00:00 2001 From: Jeff Hostetler Date: Fri, 18 Dec 2020 12:11:29 -0500 Subject: [PATCH 19/25] 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 frequency, 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 Co-authored-by: Johannes Schindelin Signed-off-by: Jeff Hostetler --- builtin/fsmonitor--daemon.c | 198 ++++++++++++++++++++++++++++++++++++ fsmonitor--daemon.h | 5 + 2 files changed, 203 insertions(+) diff --git a/builtin/fsmonitor--daemon.c b/builtin/fsmonitor--daemon.c index 0cb09ef0b98486..d6b59a98ceddd5 100644 --- a/builtin/fsmonitor--daemon.c +++ b/builtin/fsmonitor--daemon.c @@ -150,6 +150,149 @@ static int do_as_client__send_flush(void) return 0; } +enum fsmonitor_cookie_item_result { + FCIR_ERROR = -1, /* could not create cookie file ? */ + FCIR_INIT = 0, + FCIR_SEEN, + FCIR_ABORT, +}; + +struct fsmonitor_cookie_item { + struct hashmap_entry entry; + const char *name; + enum fsmonitor_cookie_item_result result; +}; + +static int cookies_cmp(const void *data, const struct hashmap_entry *he1, + const struct hashmap_entry *he2, const void *keydata) +{ + const struct fsmonitor_cookie_item *a = + container_of(he1, const struct fsmonitor_cookie_item, entry); + const struct fsmonitor_cookie_item *b = + container_of(he2, const struct fsmonitor_cookie_item, entry); + + return strcmp(a->name, keydata ? keydata : b->name); +} + +static enum fsmonitor_cookie_item_result fsmonitor_wait_for_cookie( + struct fsmonitor_daemon_state *state) +{ + int fd; + struct fsmonitor_cookie_item cookie; + struct strbuf cookie_pathname = STRBUF_INIT; + struct strbuf cookie_filename = STRBUF_INIT; + const char *slash; + int my_cookie_seq; + + pthread_mutex_lock(&state->main_lock); + + my_cookie_seq = state->cookie_seq++; + + strbuf_addbuf(&cookie_pathname, &state->path_cookie_prefix); + strbuf_addf(&cookie_pathname, "%i-%i", getpid(), my_cookie_seq); + + slash = find_last_dir_sep(cookie_pathname.buf); + if (slash) + strbuf_addstr(&cookie_filename, slash + 1); + else + strbuf_addbuf(&cookie_filename, &cookie_pathname); + cookie.name = strbuf_detach(&cookie_filename, NULL); + cookie.result = FCIR_INIT; + // TODO should we have case-insenstive hash (and in cookie_cmp()) ?? + hashmap_entry_init(&cookie.entry, strhash(cookie.name)); + + /* + * Warning: we are putting the address of a stack variable into a + * global hashmap. This feels dodgy. We must ensure that we remove + * it before this thread and stack frame returns. + */ + hashmap_add(&state->cookies, &cookie.entry); + + trace_printf_key(&trace_fsmonitor, "cookie-wait: '%s' '%s'", + cookie.name, cookie_pathname.buf); + + /* + * Create the cookie file on disk and then wait for a notification + * that the listener thread has seen it. + */ + fd = open(cookie_pathname.buf, O_WRONLY | O_CREAT | O_EXCL, 0600); + if (fd >= 0) { + close(fd); + unlink_or_warn(cookie_pathname.buf); + + while (cookie.result == FCIR_INIT) + pthread_cond_wait(&state->cookies_cond, + &state->main_lock); + + hashmap_remove(&state->cookies, &cookie.entry, NULL); + } else { + error_errno(_("could not create fsmonitor cookie '%s'"), + cookie.name); + + cookie.result = FCIR_ERROR; + hashmap_remove(&state->cookies, &cookie.entry, NULL); + } + + pthread_mutex_unlock(&state->main_lock); + + free((char*)cookie.name); + strbuf_release(&cookie_pathname); + return cookie.result; +} + +/* + * Mark these cookies as _SEEN and wake up the corresponding client threads. + */ +static void fsmonitor_cookie_mark_seen(struct fsmonitor_daemon_state *state, + const struct string_list *cookie_names) +{ + /* assert state->main_lock */ + + int k; + int nr_seen = 0; + + for (k = 0; k < cookie_names->nr; k++) { + struct fsmonitor_cookie_item key; + struct fsmonitor_cookie_item *cookie; + + key.name = cookie_names->items[k].string; + hashmap_entry_init(&key.entry, strhash(key.name)); + + cookie = hashmap_get_entry(&state->cookies, &key, entry, NULL); + if (cookie) { + trace_printf_key(&trace_fsmonitor, "cookie-seen: '%s'", + cookie->name); + cookie->result = FCIR_SEEN; + nr_seen++; + } + } + + if (nr_seen) + pthread_cond_broadcast(&state->cookies_cond); +} + +/* + * Set _ABORT on all pending cookies and wake up all client threads. + */ +static void fsmonitor_cookie_abort_all(struct fsmonitor_daemon_state *state) +{ + /* assert state->main_lock */ + + struct hashmap_iter iter; + struct fsmonitor_cookie_item *cookie; + int nr_aborted = 0; + + hashmap_for_each_entry(&state->cookies, &iter, cookie, entry) { + trace_printf_key(&trace_fsmonitor, "cookie-abort: '%s'", + cookie->name); + cookie->result = FCIR_ABORT; + nr_aborted++; + } + + if (nr_aborted) + pthread_cond_broadcast(&state->cookies_cond); +} + static int lookup_client_test_delay(void) { static int delay_ms = -1; @@ -435,6 +578,9 @@ static void fsmonitor_free_token_data(struct fsmonitor_token_data *token) * We should create a new token and start fresh (as if we just * booted up). * + * [2] Some of those lost events may have been for cookie files. We + * should assume the worst and abort them rather letting them starve. + * * If there are no readers of the the current token data series, we * can free it now. Otherwise, let the last reader free it. Either * way, the old token data series is no longer associated with our @@ -454,6 +600,8 @@ void fsmonitor_force_resync(struct fsmonitor_daemon_state *state) state->current_token_data->token_id.buf, new_one->token_id.buf); + fsmonitor_cookie_abort_all(state); + if (state->current_token_data->client_ref_count == 0) free_me = state->current_token_data; state->current_token_data = new_one; @@ -526,6 +674,7 @@ static int do_handle_client(struct fsmonitor_daemon_state *state, kh_str_t *shown; int hash_ret; int result; + enum fsmonitor_cookie_item_result cookie_result; /* * We expect `command` to be of the form: @@ -654,6 +803,39 @@ static int do_handle_client(struct fsmonitor_daemon_state *state, goto send_trivial_response; } + pthread_mutex_unlock(&state->main_lock); + + /* + * Write a cookie file inside the directory being watched in an + * effort to flush out existing filesystem events that we actually + * care about. Suspend this client thread until we see the filesystem + * events for this cookie file. + */ + cookie_result = fsmonitor_wait_for_cookie(state); + if (cookie_result != FCIR_SEEN) { + error(_("fsmonitor: cookie_result '%d' != SEEN"), + cookie_result); + result = 0; + goto send_trivial_response; + } + + pthread_mutex_lock(&state->main_lock); + + if (strcmp(requested_token_id.buf, + state->current_token_data->token_id.buf)) { + /* + * Ack! The listener thread lost sync with the filesystem + * and created a new token while we were waiting for the + * cookie file to be created! Just give up. + */ + pthread_mutex_unlock(&state->main_lock); + + trace_printf_key(&trace_fsmonitor, + "lost filesystem sync"); + result = 0; + goto send_trivial_response; + } + /* * We're going to hold onto a pointer to the current * token-data while we walk the list of batches of files. @@ -982,6 +1164,9 @@ void fsmonitor_publish(struct fsmonitor_daemon_state *state, } } + if (cookie_names->nr) + fsmonitor_cookie_mark_seen(state, cookie_names); + pthread_mutex_unlock(&state->main_lock); } @@ -1071,7 +1256,9 @@ static int fsmonitor_run_daemon(void) memset(&state, 0, sizeof(state)); + hashmap_init(&state.cookies, cookies_cmp, NULL, 0); pthread_mutex_init(&state.main_lock, NULL); + pthread_cond_init(&state.cookies_cond, NULL); state.error_code = 0; state.current_token_data = fsmonitor_new_token_data(); state.test_client_delay_ms = lookup_client_test_delay(); @@ -1094,6 +1281,15 @@ static int fsmonitor_run_daemon(void) state.nr_paths_watching = 2; } + /* + * We will write filesystem syncing cookie files into + * /-. + */ + strbuf_init(&state.path_cookie_prefix, 0); + strbuf_addbuf(&state.path_cookie_prefix, &state.path_gitdir_watch); + strbuf_addch(&state.path_cookie_prefix, '/'); + strbuf_addstr(&state.path_cookie_prefix, FSMONITOR_COOKIE_PREFIX); + /* * Confirm that we can create platform-specific resources for the * filesystem listener before we bother starting all the threads. @@ -1106,6 +1302,7 @@ static int fsmonitor_run_daemon(void) err = fsmonitor_run_daemon_1(&state); done: + pthread_cond_destroy(&state.cookies_cond); pthread_mutex_destroy(&state.main_lock); fsmonitor_fs_listen__dtor(&state); @@ -1113,6 +1310,7 @@ static int fsmonitor_run_daemon(void) strbuf_release(&state.path_worktree_watch); strbuf_release(&state.path_gitdir_watch); + strbuf_release(&state.path_cookie_prefix); return err; } diff --git a/fsmonitor--daemon.h b/fsmonitor--daemon.h index 06563b6ed56c0d..4e580e285ed6f0 100644 --- a/fsmonitor--daemon.h +++ b/fsmonitor--daemon.h @@ -45,6 +45,11 @@ struct fsmonitor_daemon_state { struct fsmonitor_token_data *current_token_data; + struct strbuf path_cookie_prefix; + pthread_cond_t cookies_cond; + int cookie_seq; + struct hashmap cookies; + int error_code; struct fsmonitor_daemon_backend_data *backend_data; From 27092d146a169d2c0be8aff6f9f274d6cc97eb0b Mon Sep 17 00:00:00 2001 From: Jeff Hostetler Date: Thu, 7 Jan 2021 16:45:13 -0500 Subject: [PATCH 20/25] fsmonitor: force update index when fsmonitor token advances Set the `FSMONITOR_CHANGED` bit on `istate->cache_changed` when the fsmonitor response contains a different token to ensure that the index is written to disk. Normally, when the fsmonitor response includes a tracked file, the index is always updated. Similarly, the index might be updated when the response alters the untracked-cache (when enabled). However, in cases where neither of those cause the index to be considered changed, the fsmonitor response is wasted. And subsequent commands will continue to make requests with the same token and if there have not been any changes in the working directory, they will receive the same response. This was observed on Windows after a large checkout. On Windows, the kernel emits events for the files that are changed as they are changed. However, it might delay events for the containing directories until the system is more idle (or someone scans the directory (so it seems)). The first status following a checkout would get the list of files. The subsequent status commands would get the list of directories as the events trickled out. But they would never catch up because the token was not advanced because the index wasn't updated. This list of directories caused `wt_status_collect_untracked()` to unnecessarily spend time actually scanning them during each command. Signed-off-by: Jeff Hostetler --- fsmonitor.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/fsmonitor.c b/fsmonitor.c index d7e18fc8cd478c..8b544e31f29f8b 100644 --- a/fsmonitor.c +++ b/fsmonitor.c @@ -353,6 +353,16 @@ void refresh_fsmonitor(struct index_state *istate) } strbuf_release(&query_result); + /* + * If the fsmonitor response and the subsequent scan of the disk + * did not cause the in-memory index to be marked dirty, then force + * it so that we advance the fsmonitor token in our extension, so + * that future requests don't keep re-requesting the same range. + */ + if (istate->fsmonitor_last_update && + strcmp(istate->fsmonitor_last_update, last_update_token.buf)) + istate->cache_changed |= FSMONITOR_CHANGED; + /* Now that we've updated istate, save the last_update_token */ FREE_AND_NULL(istate->fsmonitor_last_update); istate->fsmonitor_last_update = strbuf_detach(&last_update_token, NULL); From e36c1926a575b613bda5118491cb81e5063d1ea1 Mon Sep 17 00:00:00 2001 From: Jeff Hostetler Date: Fri, 18 Dec 2020 12:31:37 -0500 Subject: [PATCH 21/25] t7527: create test for fsmonitor--daemon Signed-off-by: Jeff Hostetler --- t/t7527-builtin-fsmonitor.sh | 485 +++++++++++++++++++++++++++++++++++ 1 file changed, 485 insertions(+) create mode 100755 t/t7527-builtin-fsmonitor.sh diff --git a/t/t7527-builtin-fsmonitor.sh b/t/t7527-builtin-fsmonitor.sh new file mode 100755 index 00000000000000..1fd230f1d4c6c7 --- /dev/null +++ b/t/t7527-builtin-fsmonitor.sh @@ -0,0 +1,485 @@ +#!/bin/sh + +test_description='built-in file system watcher' + +. ./test-lib.sh + +# Ask the fsmonitor daemon to insert a little delay before responding to +# client commands like `git status` and `git fsmonitor--daemon --query` to +# allow recent filesystem events to be received by the daemon. This helps +# the CI/PR builds be more stable. +# +# An arbitrary millisecond value. +# +GIT_TEST_FSMONITOR_CLIENT_DELAY=1000 +export GIT_TEST_FSMONITOR_CLIENT_DELAY + +git version --build-options | grep "feature:" | grep "fsmonitor--daemon" || { + skip_all="The built-in FSMonitor is not supported on this platform" + test_done +} + +kill_repo () { + r=$1 + git -C $r fsmonitor--daemon --stop >/dev/null 2>/dev/null + rm -rf $1 + return 0 +} + +start_daemon () { + case "$#" in + 1) r="-C $1";; + *) r=""; + esac + + git $r fsmonitor--daemon --start || return $? + git $r fsmonitor--daemon --is-running || return $? + + return 0 +} + +test_expect_success 'explicit daemon start and stop' ' + test_when_finished "kill_repo test_explicit" && + + git init test_explicit && + start_daemon test_explicit && + + git -C test_explicit fsmonitor--daemon --stop && + test_must_fail git -C test_explicit fsmonitor--daemon --is-running +' + +test_expect_success 'implicit daemon start' ' + test_when_finished "kill_repo test_implicit" && + + git init test_implicit && + test_must_fail git -C test_implicit fsmonitor--daemon --is-running && + + # query will implicitly start the daemon. + # + # for test-script simplicity, we send a V1 timestamp rather than + # a V2 token. either way, the daemon response to any query contains + # a new V2 token. (the daemon may complain that we sent a V1 request, + # but this test case is only concerned with whether the daemon was + # implicitly started.) + + GIT_TRACE2_EVENT="$PWD/.git/trace" \ + git -C test_implicit fsmonitor--daemon --query 0 >actual && + nul_to_q actual.filtered && + grep "builtin:" actual.filtered && + + # confirm that a daemon was started in the background. + # + # since the mechanism for starting the background daemon is platform + # dependent, just confirm that the foreground command received a + # response from the daemon. + + grep :\"query/response-length\" .git/trace && + + git -C test_implicit fsmonitor--daemon --is-running && + git -C test_implicit fsmonitor--daemon --stop && + test_must_fail git -C test_implicit fsmonitor--daemon --is-running +' + +test_expect_success 'implicit daemon stop (delete .git)' ' + test_when_finished "kill_repo test_implicit_1" && + + git init test_implicit_1 && + + start_daemon test_implicit_1 && + + # deleting the .git directory will implicitly stop the daemon. + rm -rf test_implicit_1/.git && + + # Create an empty .git directory so that the following Git command + # will stay relative to the `-C` directory. Without this, the Git + # command will (override the requested -C argument) and crawl out + # to the containing Git source tree. This would make the test + # result dependent upon whether we were using fsmonitor on our + # development worktree. + + sleep 1 && + mkdir test_implicit_1/.git && + + test_must_fail git -C test_implicit_1 fsmonitor--daemon --is-running +' + +test_expect_success 'implicit daemon stop (rename .git)' ' + test_when_finished "kill_repo test_implicit_2" && + + git init test_implicit_2 && + + start_daemon test_implicit_2 && + + # renaming the .git directory will implicitly stop the daemon. + mv test_implicit_2/.git test_implicit_2/.xxx && + + # Create an empty .git directory so that the following Git command + # will stay relative to the `-C` directory. Without this, the Git + # command will (override the requested -C argument) and crawl out + # to the containing Git source tree. This would make the test + # result dependent upon whether we were using fsmonitor on our + # development worktree. + + sleep 1 && + mkdir test_implicit_2/.git && + + test_must_fail git -C test_implicit_2 fsmonitor--daemon --is-running +' + +test_expect_success 'cannot start multiple daemons' ' + test_when_finished "kill_repo test_multiple" && + + git init test_multiple && + + start_daemon test_multiple && + + test_must_fail git -C test_multiple fsmonitor--daemon --start 2>actual && + grep "fsmonitor--daemon is already running" actual && + + git -C test_multiple fsmonitor--daemon --stop && + test_must_fail git -C test_multiple fsmonitor--daemon --is-running +' + +test_expect_success 'setup' ' + >tracked && + >modified && + >delete && + >rename && + mkdir dir1 && + >dir1/tracked && + >dir1/modified && + >dir1/delete && + >dir1/rename && + mkdir dir2 && + >dir2/tracked && + >dir2/modified && + >dir2/delete && + >dir2/rename && + mkdir dirtorename && + >dirtorename/a && + >dirtorename/b && + + cat >.gitignore <<-\EOF && + .gitignore + expect* + actual* + EOF + + git -c core.useBuiltinFSMonitor= add . && + test_tick && + git -c core.useBuiltinFSMonitor= commit -m initial && + + git config core.useBuiltinFSMonitor true +' + +test_expect_success 'update-index implicitly starts daemon' ' + test_must_fail git fsmonitor--daemon --is-running && + + GIT_TRACE2_EVENT="$PWD/.git/trace_implicit_1" \ + git update-index --fsmonitor && + + git fsmonitor--daemon --is-running && + test_might_fail git fsmonitor--daemon --stop && + + grep \"event\":\"start\".*\"fsmonitor--daemon\" .git/trace_implicit_1 +' + +test_expect_success 'status implicitly starts daemon' ' + test_must_fail git fsmonitor--daemon --is-running && + + GIT_TRACE2_EVENT="$PWD/.git/trace_implicit_2" \ + git status >actual && + + git fsmonitor--daemon --is-running && + test_might_fail git fsmonitor--daemon --stop && + + grep \"event\":\"start\".*\"fsmonitor--daemon\" .git/trace_implicit_2 +' + +edit_files() { + echo 1 >modified + echo 2 >dir1/modified + echo 3 >dir2/modified + >dir1/untracked +} + +delete_files() { + rm -f delete + rm -f dir1/delete + rm -f dir2/delete +} + +create_files() { + echo 1 >new + echo 2 >dir1/new + echo 3 >dir2/new +} + +rename_files() { + mv rename renamed + mv dir1/rename dir1/renamed + mv dir2/rename dir2/renamed +} + +file_to_directory() { + rm -f delete + mkdir delete + echo 1 >delete/new +} + +directory_to_file() { + rm -rf dir1 + echo 1 >dir1 +} + +verify_status() { + git status >actual && + GIT_INDEX_FILE=.git/fresh-index git read-tree master && + GIT_INDEX_FILE=.git/fresh-index git -c core.useBuiltinFSMonitor= status >expect && + test_cmp expect actual && + echo HELLO AFTER && + cat .git/trace && + echo HELLO AFTER +} + +# The next few test cases confirm that our fsmonitor daemon sees each type +# of OS filesystem notification that we care about. At this layer we just +# ensure we are getting the OS notifications and do not try to confirm what +# is reported by `git status`. +# +# We run a simple query after modifying the filesystem just to introduce +# a bit of a delay so that the trace logging from the daemon has time to +# get flushed to disk. +# +# We `reset` and `clean` at the bottom of each test (and before stopping the +# daemon) because these commands might implicitly restart the daemon. + +clean_up_repo_and_stop_daemon () { + git reset --hard HEAD + git clean -fd + git fsmonitor--daemon --stop + rm -f .git/trace +} + +test_expect_success 'edit some files' ' + test_when_finished "clean_up_repo_and_stop_daemon" && + + ( + GIT_TRACE_FSMONITOR="$PWD/.git/trace" && + export GIT_TRACE_FSMONITOR && + + start_daemon + ) && + + edit_files && + + git fsmonitor--daemon --query 0 >/dev/null 2>&1 && + + grep "^event: dir1/modified$" .git/trace && + grep "^event: dir2/modified$" .git/trace && + grep "^event: modified$" .git/trace && + grep "^event: dir1/untracked$" .git/trace +' + +test_expect_success 'create some files' ' + test_when_finished "clean_up_repo_and_stop_daemon" && + + ( + GIT_TRACE_FSMONITOR="$PWD/.git/trace" && + export GIT_TRACE_FSMONITOR && + + start_daemon + ) && + + create_files && + + git fsmonitor--daemon --query 0 >/dev/null 2>&1 && + + grep "^event: dir1/new$" .git/trace && + grep "^event: dir2/new$" .git/trace && + grep "^event: new$" .git/trace +' + +test_expect_success 'delete some files' ' + test_when_finished "clean_up_repo_and_stop_daemon" && + + ( + GIT_TRACE_FSMONITOR="$PWD/.git/trace" && + export GIT_TRACE_FSMONITOR && + + start_daemon + ) && + + delete_files && + + git fsmonitor--daemon --query 0 >/dev/null 2>&1 && + + grep "^event: dir1/delete$" .git/trace && + grep "^event: dir2/delete$" .git/trace && + grep "^event: delete$" .git/trace +' + +test_expect_success 'rename some files' ' + test_when_finished "clean_up_repo_and_stop_daemon" && + + ( + GIT_TRACE_FSMONITOR="$PWD/.git/trace" && + export GIT_TRACE_FSMONITOR && + + start_daemon + ) && + + rename_files && + + git fsmonitor--daemon --query 0 >/dev/null 2>&1 && + + grep "^event: dir1/rename$" .git/trace && + grep "^event: dir2/rename$" .git/trace && + grep "^event: rename$" .git/trace && + grep "^event: dir1/renamed$" .git/trace && + grep "^event: dir2/renamed$" .git/trace && + grep "^event: renamed$" .git/trace +' + +test_expect_success 'rename directory' ' + test_when_finished "clean_up_repo_and_stop_daemon" && + + ( + GIT_TRACE_FSMONITOR="$PWD/.git/trace" && + export GIT_TRACE_FSMONITOR && + + start_daemon + ) && + + mv dirtorename dirrenamed && + + git fsmonitor--daemon --query 0 >/dev/null 2>&1 && + + grep "^event: dirtorename/*$" .git/trace && + grep "^event: dirrenamed/*$" .git/trace +' + +test_expect_success 'file changes to directory' ' + test_when_finished "clean_up_repo_and_stop_daemon" && + + ( + GIT_TRACE_FSMONITOR="$PWD/.git/trace" && + export GIT_TRACE_FSMONITOR && + + start_daemon + ) && + + file_to_directory && + + git fsmonitor--daemon --query 0 >/dev/null 2>&1 && + + grep "^event: delete$" .git/trace && + grep "^event: delete/new$" .git/trace +' + +test_expect_success 'directory changes to a file' ' + test_when_finished "clean_up_repo_and_stop_daemon" && + + ( + GIT_TRACE_FSMONITOR="$PWD/.git/trace" && + export GIT_TRACE_FSMONITOR && + + start_daemon + ) && + + directory_to_file && + + git fsmonitor--daemon --query 0 >/dev/null 2>&1 && + + grep "^event: dir1$" .git/trace +' + +# The next few test cases exercise the token-resync code. When filesystem +# drops events (because of filesystem velocity or because the daemon isn't +# polling fast enough), we need to discard the cached data (relative to the +# current token) and start collecting events under a new token. +# +# the 'git fsmonitor--daemon --flush' command can be used to send a "flush" +# message to a running daemon and ask it to do a flush/resync. + +test_expect_success 'flush cached data' ' + test_when_finished "kill_repo test_flush" && + + git init test_flush && + + ( + GIT_TEST_FSMONITOR_TOKEN=true && + export GIT_TEST_FSMONITOR_TOKEN && + + GIT_TRACE_FSMONITOR="$PWD/.git/trace_daemon" && + export GIT_TRACE_FSMONITOR && + + start_daemon test_flush + ) && + + # The daemon should have an initial token with no events in _0 and + # then a few (probably platform-specific number of) events in _1. + # These should both have the same . + + git -C test_flush fsmonitor--daemon --query "builtin:test_00000001:0" >actual_0 && + nul_to_q actual_q0 && + + touch test_flush/file_1 && + touch test_flush/file_2 && + + git -C test_flush fsmonitor--daemon --query "builtin:test_00000001:0" >actual_1 && + nul_to_q actual_q1 && + + grep "file_1" actual_q1 && + + # Force a flush. This will change the , reset the , and + # flush the file data. Then create some events and ensure that the file + # again appears in the cache. It should have the new . + + git -C test_flush fsmonitor--daemon --flush >flush_0 && + nul_to_q flush_q0 && + grep "^builtin:test_00000002:0Q/Q$" flush_q0 && + + git -C test_flush fsmonitor--daemon --query "builtin:test_00000002:0" >actual_2 && + nul_to_q actual_q2 && + + grep "^builtin:test_00000002:0Q$" actual_q2 && + + touch test_flush/file_3 && + + git -C test_flush fsmonitor--daemon --query "builtin:test_00000002:0" >actual_3 && + nul_to_q actual_q3 && + + grep "file_3" actual_q3 +' + +# The next few test cases create repos where the .git directory is NOT +# inside the one of the working directory. That is, where .git is a file +# that points to a directory elsewhere. This happens for submodules and +# non-primary worktrees. + +test_expect_success 'setup worktree base' ' + git init wt-base && + echo 1 >wt-base/file1 && + git -C wt-base add file1 && + git -C wt-base commit -m "c1" +' + +test_expect_success 'worktree with .git file' ' + git -C wt-base worktree add ../wt-secondary && + + ( + GIT_TRACE2_PERF="$PWD/trace2_wt_secondary" && + export GIT_TRACE2_PERF && + + GIT_TRACE_FSMONITOR="$PWD/trace_wt_secondary" && + export GIT_TRACE_FSMONITOR && + + start_daemon wt-secondary + ) && + + git -C wt-secondary fsmonitor--daemon --stop && + test_must_fail git -C wt-secondary fsmonitor--daemon --is-running +' + +test_done From be275cd75e98fd3f2a3083160fdedf4cc4009a3b Mon Sep 17 00:00:00 2001 From: Jeff Hostetler Date: Fri, 15 Jan 2021 15:38:42 -0500 Subject: [PATCH 22/25] p7519: add fsmonitor--daemon Repeat all of the fsmonitor perf tests using `git fsmonitor--daemon` and the "Simple IPC" interface. Signed-off-by: Jeff Hostetler --- t/perf/p7519-fsmonitor.sh | 37 +++++++++++++++++++++++++++++++++++-- 1 file changed, 35 insertions(+), 2 deletions(-) diff --git a/t/perf/p7519-fsmonitor.sh b/t/perf/p7519-fsmonitor.sh index 5eb5044a103cab..2d018bc7d58993 100755 --- a/t/perf/p7519-fsmonitor.sh +++ b/t/perf/p7519-fsmonitor.sh @@ -24,7 +24,8 @@ test_description="Test core.fsmonitor" # GIT_PERF_7519_SPLIT_INDEX: used to configure core.splitIndex # GIT_PERF_7519_FSMONITOR: used to configure core.fsMonitor. May be an # absolute path to an integration. May be a space delimited list of -# absolute paths to integrations. +# absolute paths to integrations. (This hook or list of hooks does not +# include the built-in fsmonitor--daemon.) # # The big win for using fsmonitor is the elimination of the need to scan the # working directory looking for changed and untracked files. If the file @@ -135,10 +136,16 @@ test_expect_success "one time repo setup" ' setup_for_fsmonitor() { # set INTEGRATION_SCRIPT depending on the environment - if test -n "$INTEGRATION_PATH" + if test -n "$USE_FSMONITOR_DAEMON" then + git config core.useBuiltinFSMonitor true && + INTEGRATION_SCRIPT=false + elif test -n "$INTEGRATION_PATH" + then + git config core.useBuiltinFSMonitor false && INTEGRATION_SCRIPT="$INTEGRATION_PATH" else + git config core.useBuiltinFSMonitor false && # # Choose integration script based on existence of Watchman. # Fall back to an empty integration script. @@ -285,4 +292,30 @@ test_expect_success "setup without fsmonitor" ' test_fsmonitor_suite trace_stop +# +# Run a full set of perf tests using the built-in fsmonitor--daemon. +# It does not use the Hook API, so it has a different setup. +# Explicitly start the daemon here and before we start client commands +# so that we can later add custom tracing. +# + +test_lazy_prereq HAVE_FSMONITOR_DAEMON ' + git version --build-options | grep "feature:" | grep "fsmonitor--daemon" +' + +if test_have_prereq HAVE_FSMONITOR_DAEMON +then + USE_FSMONITOR_DAEMON=t + + trace_start fsmonitor--daemon--server + git fsmonitor--daemon --start + + trace_start fsmonitor--daemon--client + test_expect_success "setup for fsmonitor--daemon" 'setup_for_fsmonitor' + test_fsmonitor_suite + + git fsmonitor--daemon --stop + trace_stop +fi + test_done From 96f41e94ffbbe311a6367b8fcec24cadc2193f1c Mon Sep 17 00:00:00 2001 From: Jeff Hostetler Date: Mon, 1 Mar 2021 17:48:39 -0500 Subject: [PATCH 23/25] t7527: test status with untracked-cache and fsmonitor--daemon Create 2x2 test matrix with the untracked-cache and fsmonitor--daemon features and a series of edits and verify that status output is identical. Signed-off-by: Jeff Hostetler --- t/t7527-builtin-fsmonitor.sh | 97 ++++++++++++++++++++++++++++++++++++ 1 file changed, 97 insertions(+) diff --git a/t/t7527-builtin-fsmonitor.sh b/t/t7527-builtin-fsmonitor.sh index 1fd230f1d4c6c7..ad2188169db730 100755 --- a/t/t7527-builtin-fsmonitor.sh +++ b/t/t7527-builtin-fsmonitor.sh @@ -163,6 +163,8 @@ test_expect_success 'setup' ' .gitignore expect* actual* + flush* + trace* EOF git -c core.useBuiltinFSMonitor= add . && @@ -482,4 +484,99 @@ test_expect_success 'worktree with .git file' ' test_must_fail git -C wt-secondary fsmonitor--daemon --is-running ' +# TODO Repeat one of the "edit" tests on wt-secondary and confirm that +# TODO we get the same events and behavior -- that is, that fsmonitor--daemon +# TODO correctly listens to events on both the working directory and to the +# TODO referenced GITDIR. + +test_expect_success 'cleanup worktrees' ' + kill_repo wt-secondary && + kill_repo wt-base +' + +# The next few tests perform arbitrary/contrived file operations and +# confirm that status is correct. That is, that the data (or lack of +# data) from fsmonitor doesn't cause incorrect results. And doesn't +# cause incorrect results when the untracked-cache is enabled. + +test_lazy_prereq UNTRACKED_CACHE ' + { git update-index --test-untracked-cache; ret=$?; } && + test $ret -ne 1 +' + +test_expect_success 'Matrix: setup for untracked-cache,fsmonitor matrix' ' + test_might_fail git config --unset core.useBuiltinFSMonitor && + git update-index --no-fsmonitor && + test_might_fail git fsmonitor--daemon --stop +' + +matrix_clean_up_repo () { + git reset --hard HEAD + git clean -fd +} + +matrix_try () { + uc=$1 + fsm=$2 + fn=$3 + + test_expect_success "Matrix[uc:$uc][fsm:$fsm] $fn" ' + matrix_clean_up_repo && + $fn && + if test $uc = false -a $fsm = false + then + git status --porcelain=v1 >.git/expect.$fn + else + git status --porcelain=v1 >.git/actual.$fn + test_cmp .git/expect.$fn .git/actual.$fn + fi + ' + + return $? +} + +uc_values="false" +test_have_prereq UNTRACKED_CACHE && uc_values="false true" +for uc_val in $uc_values +do + if test $uc_val = false + then + test_expect_success "Matrix[uc:$uc_val] disable untracked cache" ' + git config core.untrackedcache false && + git update-index --no-untracked-cache + ' + else + test_expect_success "Matrix[uc:$uc_val] enable untracked cache" ' + git config core.untrackedcache true && + git update-index --untracked-cache + ' + fi + + fsm_values="false true" + for fsm_val in $fsm_values + do + if test $fsm_val = false + then + test_expect_success "Matrix[uc:$uc_val][fsm:$fsm_val] disable fsmonitor" ' + test_might_fail git config --unset core.useBuiltinFSMonitor && + git update-index --no-fsmonitor && + test_might_fail git fsmonitor--daemon --stop 2>/dev/null + ' + else + test_expect_success "Matrix[uc:$uc_val][fsm:$fsm_val] enable fsmonitor" ' + git config core.useBuiltinFSMonitor true && + git fsmonitor--daemon --start && + git update-index --fsmonitor + ' + fi + + matrix_try $uc_val $fsm_val edit_files + matrix_try $uc_val $fsm_val delete_files + matrix_try $uc_val $fsm_val create_files + matrix_try $uc_val $fsm_val rename_files + matrix_try $uc_val $fsm_val file_to_directory + matrix_try $uc_val $fsm_val directory_to_file + done +done + test_done From 68f99e65a13d6f586b24b04e0aa90e0e54e20f5f Mon Sep 17 00:00:00 2001 From: Johannes Schindelin Date: Fri, 5 Mar 2021 23:07:26 +0100 Subject: [PATCH 24/25] fsmonitor: mark the built-in FSMonitor as experimental Signed-off-by: Johannes Schindelin --- Documentation/config/core.txt | 8 +++++--- Documentation/git-fsmonitor--daemon.txt | 5 ++++- 2 files changed, 9 insertions(+), 4 deletions(-) diff --git a/Documentation/config/core.txt b/Documentation/config/core.txt index d6e2f01966cba3..bca1f6fb32330e 100644 --- a/Documentation/config/core.txt +++ b/Documentation/config/core.txt @@ -70,7 +70,8 @@ core.fsmonitor:: See the "fsmonitor-watchman" section of linkgit:githooks[5]. + Note: FSMonitor hooks (and this config setting) are ignored if the -built-in FSMonitor is enabled (see `core.useBuiltinFSMonitor`). +(experimental) built-in FSMonitor is enabled (see +`core.useBuiltinFSMonitor`). core.fsmonitorHookVersion:: Sets the version of hook that is to be used when calling the @@ -89,8 +90,9 @@ Note: FSMonitor hooks (and this config setting) are ignored if the built-in FSMonitor is enabled (see `core.useBuiltinFSMonitor`). core.useBuiltinFSMonitor:: - If set to true, enable the built-in filesystem event watcher (for - technical details, see linkgit:git-fsmonitor--daemon[1]). + (EXPERIMENTAL) If set to true, enable the built-in filesystem + event watcher (for technical details, see + linkgit:git-fsmonitor--daemon[1]). + Like external (hook-based) FSMonitors, the built-in FSMonitor can speed up Git commands that need to refresh the Git index (e.g. `git status`) in a diff --git a/Documentation/git-fsmonitor--daemon.txt b/Documentation/git-fsmonitor--daemon.txt index b94f57c97fe472..ec0012b3454d6c 100644 --- a/Documentation/git-fsmonitor--daemon.txt +++ b/Documentation/git-fsmonitor--daemon.txt @@ -3,7 +3,7 @@ git-fsmonitor--daemon(1) NAME ---- -git-fsmonitor--daemon - Builtin file system monitor daemon +git-fsmonitor--daemon - (EXPERIMENTAL) Builtin file system monitor daemon SYNOPSIS -------- @@ -20,6 +20,9 @@ SYNOPSIS DESCRIPTION ----------- +NOTE! This command is still only an experiment, subject to change dramatically +(or even to be abandoned). + Monitors files and directories in the working directory for changes using platform-specific file system notification facilities. From 8df2b476a6f625de54a1c7ca7c0f18148806d868 Mon Sep 17 00:00:00 2001 From: Johannes Schindelin Date: Fri, 5 Mar 2021 23:12:11 +0100 Subject: [PATCH 25/25] Enable the built-in FSMonitor as an experimental feature If `feature.experimental` and `feature.manyFiles` are set, we now start the built-in FSMonitor by default. Signed-off-by: Johannes Schindelin --- repo-settings.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/repo-settings.c b/repo-settings.c index bbcf71461ba22f..237dbfe61d6fbf 100644 --- a/repo-settings.c +++ b/repo-settings.c @@ -2,12 +2,13 @@ #include "config.h" #include "repository.h" #include "midx.h" +#include "fsmonitor-ipc.h" #define UPDATE_DEFAULT_BOOL(s,v) do { if (s == -1) { s = v; } } while(0) void prepare_repo_settings(struct repository *r) { - int value; + int value, feature_many_files = 0; char *strval; if (r->settings.initialized) @@ -62,6 +63,7 @@ void prepare_repo_settings(struct repository *r) r->settings.use_builtin_fsmonitor = 1; if (!repo_config_get_bool(r, "feature.manyfiles", &value) && value) { + feature_many_files = 1; UPDATE_DEFAULT_BOOL(r->settings.index_version, 4); UPDATE_DEFAULT_BOOL(r->settings.core_untracked_cache, UNTRACKED_CACHE_WRITE); } @@ -70,8 +72,12 @@ void prepare_repo_settings(struct repository *r) r->settings.fetch_write_commit_graph = value; UPDATE_DEFAULT_BOOL(r->settings.fetch_write_commit_graph, 0); - if (!repo_config_get_bool(r, "feature.experimental", &value) && value) + if (!repo_config_get_bool(r, "feature.experimental", &value) && value) { UPDATE_DEFAULT_BOOL(r->settings.fetch_negotiation_algorithm, FETCH_NEGOTIATION_SKIPPING); + if (feature_many_files && fsmonitor_ipc__is_supported()) + UPDATE_DEFAULT_BOOL(r->settings.use_builtin_fsmonitor, + 1); + } /* Hack for test programs like test-dump-untracked-cache */ if (ignore_untracked_cache_config)