From patchwork Fri Mar 25 18:03:00 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Hostetler X-Patchwork-Id: 12791943 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B1EA7C433EF for ; Fri, 25 Mar 2022 19:29:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229954AbiCYTal (ORCPT ); Fri, 25 Mar 2022 15:30:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56882 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229732AbiCYTaQ (ORCPT ); Fri, 25 Mar 2022 15:30:16 -0400 Received: from mail-ed1-x52a.google.com (mail-ed1-x52a.google.com [IPv6:2a00:1450:4864:20::52a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B303B1F37B7 for ; Fri, 25 Mar 2022 12:05:17 -0700 (PDT) Received: by mail-ed1-x52a.google.com with SMTP id z92so10252909ede.13 for ; Fri, 25 Mar 2022 12:05:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:in-reply-to:references:from:date:subject:fcc :content-transfer-encoding:mime-version:to:cc; bh=2p4/vhqS6tNu14et/Mxk5tLaAWlRCUTexkK7bM5otC8=; b=lL6xIaFY1qjffFxUiY7hk2Lj5ZmSj+/nsHP1Sf18f8RhZJFFMZbLADkaQyce3lKDT5 IzRqecn0Ge1+eqiBRD/oDLTs1SnZ2wpdnTwFqU85QoqUcs3D+B+fJdLowYv0+QZKjaF/ Hf7igruWGUY9xz77Xe3iCtLuYp8JjVyGgffCfuhpsbKgaU6s1u8lEIfWj9N0md2JqY3/ ifkvVP7pDXofiYZunDfJ1dBqi8uJ+gymD0ohJqNDwPeuo73wNFcuTqmu8RTynuS9Tbkh 6rb1rJ84HBZkKj8un60xHb7WntFHax/31NJUegRrEOKMwHP/L5YKywkZBF9d3B6+z9pj zTLA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:in-reply-to:references:from:date :subject:fcc:content-transfer-encoding:mime-version:to:cc; bh=2p4/vhqS6tNu14et/Mxk5tLaAWlRCUTexkK7bM5otC8=; b=F3W8+0sLpsGsMYxwiW5eQ4NVTQNOSXmogPdz/CXvOvT24ZoVRTtGYTqJx7mPg9TiTd Yw5ouCCFO4Y8AMmPRwjyXgQmw1KyThBZ+KNsuFjsJERkDKt8pLTRl/4AJx5DDZmadl6h jKH/5yhakPeL/k34QF9bQqjZ5/8bV2sbhQmxEwv4agOxUL/KFpMcov10e6nyAeBsseMR 9mCmFKHixxlB6nImZ/7VAEAZUhipEKqTuGE1G5DVqd6c3YI45mV1TVTmhsrSY20P+dxi Mehm1WooaEfgyeLm6Q0TikYqUK0dEllWj7xjx3+QGIEveWk919EMEW+kH5+6S1sF7+HG cF0w== X-Gm-Message-State: AOAM530s1MY9bqIZvTWUakQvrMk/bB/A3dtHs+R7ewjpXOLYQBpOeopM 7LzGbzjxm/thkm5BYcO7AVjpV8eE6F8= X-Google-Smtp-Source: ABdhPJw3i3EmGSlk90HBEgLbRLo4DfEp/DSUNvxovSQxfPrU6oWXDettiz22kGH/Br23DIulO6KRXg== X-Received: by 2002:a05:6000:1847:b0:204:1928:166a with SMTP id c7-20020a056000184700b002041928166amr10239052wri.122.1648231413906; Fri, 25 Mar 2022 11:03:33 -0700 (PDT) Received: from [127.0.0.1] ([13.74.141.28]) by smtp.gmail.com with ESMTPSA id t6-20020a05600c198600b0038cafe3d47dsm5733405wmq.42.2022.03.25.11.03.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 25 Mar 2022 11:03:33 -0700 (PDT) Message-Id: <55bd7aee06ca04e6ae9010700103a261d1255113.1648231393.git.gitgitgadget@gmail.com> In-Reply-To: References: Date: Fri, 25 Mar 2022 18:03:00 +0000 Subject: [PATCH v9 17/30] compat/fsmonitor/fsm-listen-darwin: implement FSEvent listener on MacOS Fcc: Sent MIME-Version: 1.0 To: git@vger.kernel.org Cc: Bagas Sanjaya , =?utf-8?b?w4Z2YXIgQXJuZmrDtnLDsA==?= Bjarmason , Jeff Hostetler , Eric Sunshine , Johannes Schindelin , Tao Klerks , rsbecker@nexbridge.com, Jeff Hostetler , Jeff Hostetler Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org From: Jeff Hostetler From: Jeff Hostetler 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 Signed-off-by: Junio C Hamano --- compat/fsmonitor/fsm-listen-darwin.c | 383 +++++++++++++++++++++++++++ 1 file changed, 383 insertions(+) diff --git a/compat/fsmonitor/fsm-listen-darwin.c b/compat/fsmonitor/fsm-listen-darwin.c index d2ce942cade..0741fe834c3 100644 --- a/compat/fsmonitor/fsm-listen-darwin.c +++ b/compat/fsmonitor/fsm-listen-darwin.c @@ -25,20 +25,403 @@ #include "cache.h" #include "fsmonitor.h" #include "fsm-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 int ef_is_dropped(const FSEventStreamEventFlags ef) +{ + return (ef & kFSEventStreamEventFlagMustScanSubDirs || + ef & kFSEventStreamEventFlagKernelDropped || + ef & kFSEventStreamEventFlagUserDropped); +} + +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; + struct strbuf tmp = STRBUF_INIT; + + /* + * 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, "Path: '%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 (ef_is_dropped(event_flags[k])) { + if (trace_pass_fl(&trace_fsmonitor)) + log_flags_set(path_k, event_flags[k]); + + fsmonitor_force_resync(state); + fsmonitor_batch__free_list(batch); + 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])) { + trace_printf_key(&trace_fsmonitor, + "event: gitdir removed"); + goto force_shutdown; + } + if (ef_is_root_renamed(event_flags[k])) { + trace_printf_key(&trace_fsmonitor, + "event: 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]); + + /* + * Because of the implicit "binning" (the + * kernel calls us at a given frequency) and + * de-duping (the kernel is free to combine + * multiple events for a given pathname), an + * individual fsevent could be marked as both + * a file and directory. Add it to the queue + * with both spellings so that the client will + * know how much to invalidate/refresh. + */ + + 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; + + strbuf_reset(&tmp); + strbuf_addstr(&tmp, rel); + strbuf_addch(&tmp, '/'); + + if (!batch) + batch = fsmonitor_batch__new(); + fsmonitor_batch__add_path(batch, tmp.buf); + } + + 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); + strbuf_release(&tmp); + return; + +force_shutdown: + fsmonitor_batch__free_list(batch); + string_list_clear(&cookie_list, 0); + + data->shutdown_style = FORCE_SHUTDOWN; + CFRunLoopStop(data->rl); + strbuf_release(&tmp); + return; +} + +/* + * In the call to `FSEventStreamCreate()` to setup our watch, the + * `latency` argument determines the frequency of calls to our callback + * with new FS events. Too slow and events get dropped; too fast and + * we burn CPU unnecessarily. Since it is rather obscure, I don't + * think this needs to be a config setting. I've done extensive + * testing on my systems and chosen the value below. It gives good + * results and I've not seen any dropped events. + * + * With a latency of 0.1, I was seeing lots of dropped events during + * the "touch 100000" files test within t/perf/p7519, but with a + * latency of 0.001 I did not see any dropped events. So I'm going + * to assume that this is the "correct" value. + * + * https://developer.apple.com/documentation/coreservices/1443980-fseventstreamcreate + */ int fsm_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]; + + CALLOC_ARRAY(data, 1); + 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 fsm_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 fsm_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 fsm_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; }