From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS3215 2.6.0.0/16 X-Spam-Status: No, score=-3.4 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,T_SCC_BODY_TEXT_LINE shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from out1.vger.email (out1.vger.email [IPv6:2620:137:e000::1:20]) by dcvr.yhbt.net (Postfix) with ESMTP id 7AC691F8C5 for ; Thu, 24 Mar 2022 16:50:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345677AbiCXQwL (ORCPT ); Thu, 24 Mar 2022 12:52:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58676 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1351854AbiCXQvp (ORCPT ); Thu, 24 Mar 2022 12:51:45 -0400 Received: from mail-wm1-x32b.google.com (mail-wm1-x32b.google.com [IPv6:2a00:1450:4864:20::32b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 551AC90CDA for ; Thu, 24 Mar 2022 09:50:12 -0700 (PDT) Received: by mail-wm1-x32b.google.com with SMTP id r64so3091417wmr.4 for ; Thu, 24 Mar 2022 09:50:12 -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=E71KNgTg0q8XCvxrZSji2F8TZ6CX5yg0f7+6kMHO1JqXBkA/xsJoTA0WkhpnmH+lNY YmNth6oIjt0wCdJosG7UPKP67eEED74jV4B8fb4VnPo2GZXzHVdpl2LnG43smCJkqbGQ s0vYgpnzklX+ATmb6JsnidqkWD3sy4kLzcdITsG+BrxiGhC2TXCOwmIILrqDzDftrROE CNeir47LlJpZh6X8Yq/3GnkTJW335tn9IWi2sPeGgx6i1yxqEMnxSz4mAqN4cjJ7UwMq Z4+3i+HwNojpLjCh2ci4UmswdMLP6SSzO7uJQSiGhsJy2b9CHoTGom0mKXUnCGDfu4iJ 6wQA== 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=ZH3RUsjgJX0TaPQhvHd3fHFaomVboQVfCmAkCVZaA3cdowPWVH1tv0Uei3e102G3cp vEJSE/oWLopKIaM9ANQ1sxZbapiG9/ZEV6JScP4298fh/aCd85KnrEG8B+ZzQx2YTnIO 90i/ccnJTdZTO8l0KVerLk8D9wS/HF9bFX1YSnD0SLeZdymMB2Gc9RRWynTo2ZCLdC/k kHJ2W4IQZWXZ33eadGQiupHoGoJCxuVeePV7cg2lbGpVB1I1MwBZoMGLP/SA9fxALN5Y ihpi25muAjtlbRcD2p+m/lZidoE/4BleTBelnWQIXs43Kjna8AQD7oTi4tN0gdjTUBBZ hCXQ== X-Gm-Message-State: AOAM530n4hS2UhPp8vRASGX7M5xBHoBnMIhiijLIEbRl1V7eoHnaI2sO znqby8xuGB8Dnnpp5zpZ5WgS6tqJpnc= X-Google-Smtp-Source: ABdhPJyzyAplvQHH+o+K08nIGDcvgSRKfBSzhyN3XIC8uhgB5pvHvqgN2JO5+Ska9cDpXYEs7ysLtw== X-Received: by 2002:a1c:cc12:0:b0:389:7c46:94d with SMTP id h18-20020a1ccc12000000b003897c46094dmr14665370wmb.119.1648140610408; Thu, 24 Mar 2022 09:50:10 -0700 (PDT) Received: from [127.0.0.1] ([13.74.141.28]) by smtp.gmail.com with ESMTPSA id a4-20020a05600c348400b0038cd743830esm1284854wmq.29.2022.03.24.09.50.09 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 24 Mar 2022 09:50:09 -0700 (PDT) Message-Id: <55bd7aee06ca04e6ae9010700103a261d1255113.1648140586.git.gitgitgadget@gmail.com> In-Reply-To: References: From: "Jeff Hostetler via GitGitGadget" Date: Thu, 24 Mar 2022 16:49:33 +0000 Subject: [PATCH v8 17/30] compat/fsmonitor/fsm-listen-darwin: implement FSEvent listener on MacOS Fcc: Sent Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit MIME-Version: 1.0 To: git@vger.kernel.org Cc: Bagas Sanjaya , =?UTF-8?Q?=C3=86var_Arnfj=C3=B6r=C3=B0?= Bjarmason , Jeff Hostetler , Eric Sunshine , Johannes Schindelin , Tao Klerks , Jeff Hostetler , Jeff Hostetler Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org 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; } -- gitgitgadget