Refactor code to replace usages of deprecated function FSEventStreamS…

…cheduleWithRunLoop with FSEventStreamSetDispatchQueue

Update NEWS

NEWS

@@ -3,7 +3,11 @@ NEWS
 
 New in master:
 
-  * Issue 230: Improve responsiveness on macos: add support for kFSEventStreamCreateFlagNoDefer.
+  * Refactor code to replace usages of deprecated function
+    FSEventStreamScheduleWithRunLoop with FSEventStreamSetDispatchQueue.
+
+  * Issue 230: Improve responsiveness on macos: add support for
+    kFSEventStreamCreateFlagNoDefer.
 
   * Issue 249: Man page still mentions fswatch-run.
 

configure.ac

@@ -1,6 +1,6 @@
 #                                               -*- Autoconf -*-
 #
-# Copyright (C) 2014-2021 Enrico M. Crisostomo
+# Copyright (C) 2014-2022 Enrico M. Crisostomo
 #
 # This program is free software; you can redistribute it and/or modify it under
 # the terms of the GNU General Public License as published by the Free Software
@@ -16,12 +16,12 @@
 #
 # Process this file with autoconf to produce a configure script.
 #
-dnl Copyright (C) 2014-2021 Enrico M. Crisostomo
+dnl Copyright (C) 2014-2022 Enrico M. Crisostomo
 AC_PREREQ([2.69])
 m4_include([m4/fswatch_version.m4])
 m4_include([m4/libfswatch_version.m4])
 AC_INIT([fswatch], LIBFSWATCH_VERSION, [[email protected]], [], [https://github.com/emcrisostomo/fswatch])
-AC_COPYRIGHT([2013-2021 (C) Enrico M. Crisostomo])
+AC_COPYRIGHT([2013-2022 (C) Enrico M. Crisostomo])
 AC_REVISION([$Revision: LIBFSWATCH_REVISION$])
 AC_CONFIG_SRCDIR([fswatch/src/fswatch.cpp])
 AC_CONFIG_AUX_DIR([config])
@@ -129,13 +129,13 @@ AS_VAR_SET_IF([IS_DARWIN], [
   AX_COMPARE_VERSION([${DARWIN_VER}], [ge], [11.0], [AC_DEFINE([HAVE_MACOS_GE_10_7],  [1], ["macOS is at least the specified version"])])
   AX_COMPARE_VERSION([${DARWIN_VER}], [ge], [13.0], [AC_DEFINE([HAVE_MACOS_GE_10_9],  [1], ["macOS is at least the specified version"])])
   AX_COMPARE_VERSION([${DARWIN_VER}], [ge], [14.0], [AC_DEFINE([HAVE_MACOS_GE_10_10], [1], ["macOS is at least the specified version"])])
+  # Check for macOS FSEvents.  FSEvents added file events in a later release, so
+  # this check must be performed separately.
+  AC_CHECK_HEADERS([CoreServices/CoreServices.h])
+  AS_VAR_IF([ac_cv_header_CoreServices_CoreServices_h], ["yes"], [AX_FSEVENTS_HAVE_FILE_EVENTS])
 ])
 
-# Check for macOS FSEvents.  FSEvents added file events in a later release, so
-# this check must be performed separately.
-AC_CHECK_HEADERS([CoreServices/CoreServices.h])
-AS_VAR_IF([ac_cv_header_CoreServices_CoreServices_h], ["yes"], [AX_FSEVENTS_HAVE_FILE_EVENTS])
-AM_CONDITIONAL([USE_FSEVENTS], [test "x${ax_cv_fsevents_have_file_events}" = "xyes"])
+AM_CONDITIONAL([USE_FSEVENTS], [test "x${ax_cv_fsevents_have_fseventstreamsetdispatchqueue}" = "xyes"])
 
 # Check for kqueue: if the sys/event.h header is present, perform a check for
 # the kqueue and kevent functions.

fswatch/src/fswatch.cpp

@@ -35,7 +35,7 @@
 #include "libfswatch/c/libfswatch.h"
 #include "libfswatch/c/libfswatch_log.h"
 #include "libfswatch/c++/libfswatch_exception.hpp"
-#ifdef HAVE_FSEVENTS_FILE_EVENTS
+#ifdef HAVE_FSEVENTS_FSEVENTSTREAMSETDISPATCHQUEUE
   #include "libfswatch/c++/fsevents_monitor.hpp"
 #endif
 
@@ -172,7 +172,7 @@ static void usage(std::ostream& stream)
   stream << " -i, --include=REGEX   " << _("Include paths matching REGEX.\n");
   stream << " -I, --insensitive     " << _("Use case insensitive regular expressions.\n");
   stream << " -l, --latency=DOUBLE  " << _("Set the latency.\n");
-  #if defined(HAVE_FSEVENTS_FILE_EVENTS)
+  #if defined(HAVE_FSEVENTS_FSEVENTSTREAMSETDISPATCHQUEUE)
   stream << "     --no-defer        " << _("Set the no defer flag in the monitor.\n");
   #endif
   stream << " -L, --follow-links    " << _("Follow symbolic links.\n");
@@ -494,7 +494,7 @@ static void start_monitor(int argc, char **argv, int optind)
   active_monitor->set_properties(monitor_properties);
   active_monitor->set_allow_overflow(allow_overflow);
   active_monitor->set_latency(lvalue);
-  #if defined(HAVE_FSEVENTS_FILE_EVENTS)
+  #if defined(HAVE_FSEVENTS_FSEVENTSTREAMSETDISPATCHQUEUE)
   if (noDeferFlag)
     active_monitor->set_property(std::string(fsw::fsevents_monitor::DARWIN_EVENTSTREAM_NO_DEFER), "true");
   #endif
@@ -537,7 +537,7 @@ static void parse_opts(int argc, char **argv)
     {"include",              required_argument, nullptr,       'i'},
     {"insensitive",          no_argument,       nullptr,       'I'},
     {"latency",              required_argument, nullptr,       'l'},
-  #ifdef HAVE_FSEVENTS_FILE_EVENTS
+  #ifdef HAVE_FSEVENTS_FSEVENTSTREAMSETDISPATCHQUEUE
     {"no-defer",             no_argument,       nullptr,       OPT_NO_DEFER},
   #endif
     {"list-monitors",        no_argument,       nullptr,       'M'},

libfswatch/src/libfswatch/c++/fsevents_monitor.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2014-2021 Enrico M. Crisostomo
+ * Copyright (c) 2014-2022 Enrico M. Crisostomo
  *
  * This program is free software; you can redistribute it and/or modify it under
  * the terms of the GNU General Public License as published by the Free Software
@@ -17,6 +17,7 @@
 #include <memory>
 #include <unistd.h> // isatty()
 #include <cstdio> // fileno()
+#include <thread>
 #include "fsevents_monitor.hpp"
 #include "libfswatch/gettext_defs.h"
 #include "libfswatch_exception.hpp"
@@ -120,14 +121,9 @@ namespace fsw
     if (!stream)
       throw libfsw_exception(_("Event stream could not be created."));
 
-    // Fire the event loop
-    run_loop = CFRunLoopGetCurrent();
-
-    // Loop Initialization
-    FSW_ELOG(_("Scheduling stream with run loop...\n"));
-    FSEventStreamScheduleWithRunLoop(stream,
-                                     run_loop,
-                                     kCFRunLoopDefaultMode);
+    // Creating dispatch queue
+    fsevents_queue = dispatch_queue_create("fswatch_event_queue", NULL);
+    FSEventStreamSetDispatchQueue(stream, fsevents_queue);
 
     FSW_ELOG(_("Starting event stream...\n"));
     FSEventStreamStart(stream);
@@ -136,9 +132,16 @@ namespace fsw
     run_loop_lock.unlock();
 #endif
 
-    // Loop
-    FSW_ELOG(_("Starting run loop...\n"));
-    CFRunLoopRun();
+    for(;;)
+    {
+#ifdef HAVE_CXX_MUTEX
+      run_loop_lock.lock();
+      if (should_stop) break;
+      run_loop_lock.unlock();
+#endif
+
+      std::this_thread::sleep_for(std::chrono::milliseconds((long long) (latency * 1000)));
+    }
 
     // Deinitialization part
     FSW_ELOG(_("Stopping event stream...\n"));
@@ -150,22 +153,10 @@ namespace fsw
     FSW_ELOG(_("Releasing event stream...\n"));
     FSEventStreamRelease(stream);
 
+    dispatch_release(fsevents_queue);
     stream = nullptr;
   }
 
-  /*
-   * on_stop() is designed to be invoked with a lock on the run_mutex.
-   */
-  void fsevents_monitor::on_stop()
-  {
-    if (!run_loop) throw libfsw_exception(_("run loop is null"));
-
-    FSW_ELOG(_("Stopping run loop...\n"));
-    CFRunLoopStop(run_loop);
-
-    run_loop = nullptr;
-  }
-
   static vector<fsw_event_flag> decode_flags(FSEventStreamEventFlags flag)
   {
     vector<fsw_event_flag> evt_flags;

libfswatch/src/libfswatch/c++/fsevents_monitor.hpp

@@ -80,11 +80,6 @@ namespace fsw
      */
     void run() override;
 
-    /**
-     * @brief Execute an implementation-specific stop handler.
-     */
-    void on_stop() override;
-
   private:
     static void fsevents_callback(ConstFSEventStreamRef streamRef,
                                   void *clientCallBackInfo,
@@ -94,7 +89,7 @@ namespace fsw
                                   const FSEventStreamEventId eventIds[]);
 
     FSEventStreamRef stream = nullptr;
-    CFRunLoopRef run_loop = nullptr;
+    dispatch_queue_t fsevents_queue = nullptr;
     bool no_defer();
     void create_stream(CFArrayRef pathsToWatch);
   };

libfswatch/src/libfswatch/c++/monitor_factory.cpp

@@ -18,7 +18,7 @@
 #include "libfswatch/gettext_defs.h"
 #include "monitor_factory.hpp"
 #include "libfswatch_exception.hpp"
-#if defined(HAVE_FSEVENTS_FILE_EVENTS)
+#if defined(HAVE_FSEVENTS_FSEVENTSTREAMSETDISPATCHQUEUE)
   #include "fsevents_monitor.hpp"
 #endif
 #if defined(HAVE_SYS_EVENT_H)
@@ -43,7 +43,7 @@ namespace fsw
   {
     fsw_monitor_type type;
 
-#if defined(HAVE_FSEVENTS_FILE_EVENTS)
+#if defined(HAVE_FSEVENTS_FSEVENTSTREAMSETDISPATCHQUEUE)
     type = fsw_monitor_type::fsevents_monitor_type;
 #elif defined(HAVE_SYS_EVENT_H)
     type = fsw_monitor_type::kqueue_monitor_type;
@@ -73,7 +73,7 @@ namespace fsw
     case system_default_monitor_type:
       return create_default_monitor(paths, callback, context);
 
-#if defined(HAVE_FSEVENTS_FILE_EVENTS)
+#if defined(HAVE_FSEVENTS_FSEVENTSTREAMSETDISPATCHQUEUE)
       case fsevents_monitor_type:
         return new fsevents_monitor(paths, callback, context);
 #endif
@@ -105,7 +105,7 @@ namespace fsw
 #define fsw_quote(x) #x
     static std::map<std::string, fsw_monitor_type> creator_by_string_set;
 
-#if defined(HAVE_FSEVENTS_FILE_EVENTS)
+#if defined(HAVE_FSEVENTS_FSEVENTSTREAMSETDISPATCHQUEUE)
     creator_by_string_set[fsw_quote(fsevents_monitor)] = fsw_monitor_type::fsevents_monitor_type;
 #endif
 #if defined(HAVE_SYS_EVENT_H)