Added LinuxProduceSyntheticEvents option for issue #192.

Author: SpartanJ

.ecode/project_build.json

@@ -31,7 +31,16 @@
         "preset": "generic",
         "relative_file_paths": true
       }
-    }
+    },
+    "run": [
+      {
+        "args": "",
+        "command": "efsw-test-debug",
+        "name": "efsw-test-debug",
+        "run_in_terminal": true,
+        "working_dir": "${project_root}/bin"
+      }
+    ]
   },
   "linux-release": {
     "build": [

include/efsw/efsw.h

@@ -106,6 +106,13 @@ enum efsw_option {
 	/// the number of events reported. This will have an small performance and memory impact as a
 	/// consequence.
 	EFSW_OPT_MAC_SANITIZE_EVENTS = 4,
+	/// Linux does not support natively recursive watchers. This means that when using recursive
+	/// watches efsw registers new watchers for each directory. If new file are created between
+	/// the time efsw takes to register the new directory those events might be missed. To avoid
+	/// missing new file notifications efsw will trigger synthetic new file events for existing
+	/// files in the new directroy watched. This might have the unintended consequence of sending
+	/// duplicated created events due to the system also emitting this event.
+	LINUX_PRODUCE_SYNTHETIC_EVENTS = 5,
 };
 
 /// Basic interface for listening for file events.

include/efsw/efsw.hpp

@@ -148,6 +148,13 @@ enum Option {
 	/// the number of events reported. This will have an small performance and memory impact as a
 	/// consequence.
 	MacSanitizeEvents = 4,
+	/// Linux does not support natively recursive watchers. This means that when using recursive
+	/// watches efsw registers new watchers for each directory. If new file are created between
+	/// the time efsw takes to register the new directory those events might be missed. To avoid
+	/// missing new file notifications efsw will trigger synthetic created file events for existing
+	/// files in the new directroy watched. This might have the unintended consequence of sending
+	/// duplicated created events due to the system also emitting this event.
+	LinuxProduceSyntheticEvents = 5,
 };
 }
 typedef Options::Option Option;

src/efsw/FileWatcherInotify.cpp

@@ -69,15 +69,17 @@ FileWatcherInotify::~FileWatcherInotify() {
 }
 
 WatchID FileWatcherInotify::addWatch( const std::string& directory, FileWatchListener* watcher,
-									  bool recursive, const std::vector<WatcherOption>& ) {
+									  bool recursive, const std::vector<WatcherOption>& options ) {
 	if ( !mInitOK )
 		return Errors::Log::createLastError( Errors::Unspecified, directory );
 	Lock initLock( mInitLock );
-	return addWatch( directory, watcher, recursive, NULL );
+	bool syntheticEvents = getOptionValue( options, Options::LinuxProduceSyntheticEvents, 0 ) != 0;
+	return addWatch( directory, watcher, recursive, syntheticEvents, NULL );
 }
 
 WatchID FileWatcherInotify::addWatch( const std::string& directory, FileWatchListener* watcher,
-									  bool recursive, WatcherInotify* parent ) {
+									  bool recursive, bool syntheticEvents,
+									  WatcherInotify* parent, bool fromInternalEvent ) {
 	std::string dir( directory );
 
 	FileSystem::dirAddSlashAtEnd( dir );
@@ -160,7 +162,17 @@ WatchID FileWatcherInotify::addWatch( const std::string& directory, FileWatchLis
 			const FileInfo& cfi = it->second;
 
 			if ( cfi.isDirectory() && cfi.isReadable() ) {
-				addWatch( cfi.Filepath, watcher, recursive, pWatch );
+				addWatch( cfi.Filepath, watcher, recursive, syntheticEvents, pWatch );
+			}
+		}
+
+		if ( fromInternalEvent && parent != NULL && syntheticEvents ) {
+			for ( const auto& file : files ) {
+				if ( file.second.isRegularFile() ) {
+					pWatch->Listener->handleFileAction(
+						pWatch->ID, pWatch->Directory,
+						FileSystem::fileNameFromPath( file.second.Filepath ), Actions::Add );
+				}
 			}
 		}
 	}
@@ -448,8 +460,9 @@ void FileWatcherInotify::checkForNewWatcher( Watcher* watch, std::string fpath )
 		}
 
 		if ( !found ) {
-			addWatch( fpath, watch->Listener, watch->Recursive,
-					  static_cast<WatcherInotify*>( watch ) );
+			WatcherInotify* iWatch = static_cast<WatcherInotify*>( watch );
+			addWatch( fpath, watch->Listener, watch->Recursive, iWatch->syntheticEvents,
+					  static_cast<WatcherInotify*>( watch ), true );
 		}
 	}
 }

src/efsw/FileWatcherInotify.hpp

@@ -65,7 +65,8 @@ class FileWatcherInotify : public FileWatcherImpl {
 	std::vector<std::pair<WatcherInotify*, std::string>> mMovedOutsideWatches;
 
 	WatchID addWatch( const std::string& directory, FileWatchListener* watcher, bool recursive,
-					  WatcherInotify* parent = NULL );
+					  bool syntheticEvents, WatcherInotify* parent = NULL,
+					  bool fromInternalEvent = false );
 
 	bool pathInWatches( const std::string& path ) override;
 

src/efsw/WatcherInotify.hpp

@@ -16,6 +16,7 @@ class WatcherInotify : public Watcher {
 	WatchID InotifyID;
 
 	FileInfo DirInfo;
+	bool syntheticEvents{ false };
 };
 
 } // namespace efsw