#include "builtin.h" #include "config.h" #include "parse-options.h" #include "fsmonitor.h" #include "fsmonitor-ipc.h" #include "compat/fsmonitor/fsm-listen.h" #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 []"), N_("git fsmonitor--daemon run []"), N_("git fsmonitor--daemon stop"), N_("git fsmonitor--daemon status"), NULL }; #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; #define FSMONITOR__ANNOUNCE_STARTUP "fsmonitor.announcestartup" static int fsmonitor__announce_startup = 0; 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; } if (!strcmp(var, FSMONITOR__ANNOUNCE_STARTUP)) { int is_bool; int i = git_config_bool_or_int(var, value, &is_bool); if (i < 0) return error(_("value of '%s' not bool or int: %d"), var, i); fsmonitor__announce_startup = i; return 0; } return git_default_config(var, value, cb); } /* * 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; } static int do_as_client__status(void) { enum ipc_active_state state = fsmonitor_ipc__get_state(); switch (state) { case IPC_STATE__LISTENING: printf(_("fsmonitor-daemon is watching '%s'\n"), the_repository->worktree); return 0; default: printf(_("fsmonitor-daemon is not watching '%s'\n"), the_repository->worktree); return 1; } } /* * 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 "builtin" prefix is used as a namespace to avoid conflicts * with other providers (such as Watchman). * * 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 whenever the * daemon needs to make its state public. For example, if 1000 file * system events come in, but no clients have requested the data, * the daemon can continue to accumulate file changes in the same * bin and does not need to advance the sequence number. However, * as soon as a client does arrive, the daemon needs to start a new * bin and increment the sequence number. * * The sequence number serves as the boundary between 2 sets * of bins -- the older ones that the client has already seen * and the newer ones that it hasn't. * * 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). * * 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; }; struct fsmonitor_batch { struct fsmonitor_batch *next; uint64_t batch_seq_nr; const char **interned_paths; size_t nr, alloc; time_t pinned_time; }; 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; struct fsmonitor_batch *batch; CALLOC_ARRAY(token, 1); batch = fsmonitor_batch__new(); strbuf_init(&token->token_id, 0); token->batch_head = batch; token->batch_tail = batch; 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++); } /* * We created a new and are starting a new series * of tokens with a zero . * * Since clients cannot guess our new (non test) * they will always receive a trivial response (because of the * mismatch on the ). The trivial response will * tell them our new so that subsequent requests * will be relative to our new series. (And when sending that * response, we pin the current head of the batch list.) * * Even if the client correctly guesses the , their * request of "builtin::0" asks for all changes MORE * RECENT than batch/bin 0. * * This implies that it is a waste to accumulate paths in the * initial batch/bin (because they will never be transmitted). * * So the daemon could be running for days and watching the * file system, but doesn't need to actually accumulate any * paths UNTIL we need to set a reference point for a later * relative request. * * However, it is very useful for testing to always have a * reference point set. Pin batch 0 to force early file system * events to accumulate. */ if (test_env_value) batch->pinned_time = time(NULL); return token; } struct fsmonitor_batch *fsmonitor_batch__new(void) { struct fsmonitor_batch *batch; CALLOC_ARRAY(batch, 1); return batch; } void fsmonitor_batch__free_list(struct fsmonitor_batch *batch) { while (batch) { struct fsmonitor_batch *next = batch->next; /* * The actual strings within the array of this batch * are interned, so we don't own them. We only own * the array. */ free(batch->interned_paths); free(batch); batch = 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) { 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) { if (!token) return; assert(token->client_ref_count == 0); strbuf_release(&token->token_id); fsmonitor_batch__free_list(token->batch_head); 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 concurrent threads reading 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. */ static void with_lock__do_force_resync(struct fsmonitor_daemon_state *state) { /* assert current thread holding state->main_lock */ struct fsmonitor_token_data *free_me = NULL; struct fsmonitor_token_data *new_one = NULL; new_one = fsmonitor_new_token_data(); if (state->current_token_data->client_ref_count == 0) free_me = state->current_token_data; state->current_token_data = new_one; fsmonitor_free_token_data(free_me); } void fsmonitor_force_resync(struct fsmonitor_daemon_state *state) { pthread_mutex_lock(&state->main_lock); with_lock__do_force_resync(state); pthread_mutex_unlock(&state->main_lock); } /* * Format an opaque token string to send to the client. */ static void with_lock__format_response_token( struct strbuf *response_token, const struct strbuf *response_token_id, const struct fsmonitor_batch *batch) { /* assert current thread holding state->main_lock */ strbuf_reset(response_token); strbuf_addf(response_token, "builtin:%s:%"PRIu64, response_token_id->buf, batch->batch_seq_nr); } /* * Parse an opaque token from the client. * Returns -1 on error. */ 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 do_trivial = 0; int do_flush = 0; /* * 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; } else 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. */ do_flush = 1; do_trivial = 1; } else 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); do_trivial = 1; } else { /* We have "builtin:*" */ 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); do_trivial = 1; } else { /* * We have a V2 valid token: * "builtin::" */ } } pthread_mutex_lock(&state->main_lock); if (!state->current_token_data) BUG("fsmonitor state does not have a current token"); if (do_flush) with_lock__do_force_resync(state); /* * 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; batch_head = token_data->batch_head; ((struct fsmonitor_batch *)batch_head)->pinned_time = time(NULL); /* * 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". We send the seq_nr of the just-pinned * head batch so that future requests from a client will be relative * to it. */ with_lock__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); if (!do_trivial) { if (strcmp(requested_token_id.buf, 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. */ trace2_data_string("fsmonitor", the_repository, "response/token", "different"); do_trivial = 1; } else if (requested_oldest_seq_nr < 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. */ trace_printf_key(&trace_fsmonitor, "client requested truncated data"); do_trivial = 1; } } if (do_trivial) { pthread_mutex_unlock(&state->main_lock); reply(reply_data, "/", 2); trace2_data_intmax("fsmonitor", the_repository, "response/trivial", 1); goto cleanup; } /* * 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`). */ token_data->client_ref_count++; pthread_mutex_unlock(&state->main_lock); /* * The client request is relative to the token that they sent, * so walk the batch list backwards from the current head back * to the batch (sequence number) they named. * * We use khash to de-dup the list of pathnames. * * NEEDSWORK: each batch contains a list of interned strings, * so we only need to do pointer comparisons here to build the * hash table. Currently, we're still comparing the string * values. */ 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); cleanup: strbuf_release(&response_token); strbuf_release(&requested_token_id); strbuf_release(&payload); return 0; } static ipc_server_application_cb handle_client; static int handle_client(void *data, const char *command, size_t command_len, ipc_server_reply_cb *reply, struct ipc_server_reply_data *reply_data) { struct fsmonitor_daemon_state *state = data; int result; /* * The Simple IPC API now supports {char*, len} arguments, but * FSMonitor always uses proper null-terminated strings, so * we can ignore the command_len argument. (Trust, but verify.) */ if (command_len != strlen(command)) BUG("FSMonitor assumes text messages"); 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 = do_handle_client(state, command, reply, reply_data); trace2_region_leave("fsmonitor", "handle_client", the_repository); 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); } /* * 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) { BUG("token does not have 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->batch_seq_nr) { /* * Batch 0 is unpinned. See the note in * `fsmonitor_new_token_data()` about why we * don't need to accumulate these paths. */ fsmonitor_batch__free_list(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 add the paths in the given * batch onto the end of the current head batch. */ fsmonitor_batch__combine(head, batch); fsmonitor_batch__free_list(batch); } } pthread_mutex_unlock(&state->main_lock); } static void *fsm_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); fsm_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; } 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_errno( _("could not start IPC thread pool on '%s'"), fsmonitor_ipc__get_path()); /* * Start the fsmonitor listener thread to collect filesystem * events. */ if (pthread_create(&state->listener_thread, NULL, fsm_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. */ fsm_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 = fsmonitor_new_token_data(); /* 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; /* * We create and delete cookie files somewhere inside the .git * directory to help us keep sync with the file system. If * ".git" is not a directory, then is not inside the * cone of , so set up a second watch to watch * the so that we get events for the cookie files. */ 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 (fsm_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); fsm_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 try_to_run_foreground_daemon(int detach_console) { /* * 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 (fsmonitor_ipc__get_state() == IPC_STATE__LISTENING) die(_("fsmonitor--daemon is already running '%s'"), the_repository->worktree); if (fsmonitor__announce_startup) { fprintf(stderr, _("running fsmonitor-daemon in '%s'\n"), the_repository->worktree); fflush(stderr); } #ifdef GIT_WINDOWS_NATIVE if (detach_console) FreeConsole(); #endif return !!fsmonitor_run_daemon(); } static start_bg_wait_cb bg_wait_cb; static int bg_wait_cb(const struct child_process *cp, void *cb_data) { enum ipc_active_state s = fsmonitor_ipc__get_state(); switch (s) { case IPC_STATE__LISTENING: /* child is "ready" */ return 0; case IPC_STATE__NOT_LISTENING: case IPC_STATE__PATH_NOT_FOUND: /* give child more time */ return 1; default: case IPC_STATE__INVALID_PATH: case IPC_STATE__OTHER_ERROR: /* all the time in world won't help */ return -1; } } static int try_to_start_background_daemon(void) { struct child_process cp = CHILD_PROCESS_INIT; enum start_bg_result sbgr; /* * 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 (fsmonitor_ipc__get_state() == IPC_STATE__LISTENING) die(_("fsmonitor--daemon is already running '%s'"), the_repository->worktree); if (fsmonitor__announce_startup) { fprintf(stderr, _("starting fsmonitor-daemon in '%s'\n"), the_repository->worktree); fflush(stderr); } cp.git_cmd = 1; strvec_push(&cp.args, "fsmonitor--daemon"); strvec_push(&cp.args, "run"); strvec_push(&cp.args, "--detach"); strvec_pushf(&cp.args, "--ipc-threads=%d", fsmonitor__ipc_threads); cp.no_stdin = 1; cp.no_stdout = 1; cp.no_stderr = 1; sbgr = start_bg_command(&cp, bg_wait_cb, NULL, fsmonitor__start_timeout_sec); switch (sbgr) { case SBGR_READY: return 0; default: case SBGR_ERROR: case SBGR_CB_ERROR: return error(_("daemon failed to start")); case SBGR_TIMEOUT: return error(_("daemon not online yet")); case SBGR_DIED: return error(_("daemon terminated")); } } int cmd_fsmonitor__daemon(int argc, const char **argv, const char *prefix) { const char *subcmd; int detach_console = 0; struct option options[] = { OPT_BOOL(0, "detach", &detach_console, N_("detach from console")), 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() }; git_config(fsmonitor_config, NULL); argc = parse_options(argc, argv, prefix, options, builtin_fsmonitor__daemon_usage, 0); if (argc != 1) usage_with_options(builtin_fsmonitor__daemon_usage, options); subcmd = argv[0]; if (fsmonitor__ipc_threads < 1) die(_("invalid 'ipc-threads' value (%d)"), fsmonitor__ipc_threads); if (!strcmp(subcmd, "start")) return !!try_to_start_background_daemon(); if (!strcmp(subcmd, "run")) return !!try_to_run_foreground_daemon(detach_console); if (!strcmp(subcmd, "stop")) return !!do_as_client__send_stop(); if (!strcmp(subcmd, "status")) return !!do_as_client__status(); die(_("Unhandled subcommand '%s'"), subcmd); } #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