internal void Start()
{
// Make sure _fullPath doesn't contain a link or alias
// since the OS will give back the actual, non link'd or alias'd paths
_fullDirectory = Interop.Sys.RealPath(_fullDirectory);
if (_fullDirectory == null)
{
throw Interop.GetExceptionForIoErrno(Interop.Sys.GetLastErrorInfo(), _fullDirectory, true);
}
Debug.Assert(string.IsNullOrEmpty(_fullDirectory) == false, "Watch directory is null or empty");
// Normalize the _fullDirectory path to have a trailing slash
if (_fullDirectory [_fullDirectory.Length - 1] != '/')
{
_fullDirectory += "/";
}
// Get the path to watch and verify we created the CFStringRef
SafeCreateHandle path = Interop.CoreFoundation.CFStringCreateWithCString(_fullDirectory);
if (path.IsInvalid)
{
throw Interop.GetExceptionForIoErrno(Interop.Sys.GetLastErrorInfo(), _fullDirectory, true);
}
// Take the CFStringRef and put it into an array to pass to the EventStream
SafeCreateHandle arrPaths = Interop.CoreFoundation.CFArrayCreate(new CFStringRef [1] {
path.DangerousGetHandle()
}, (UIntPtr)1);
if (arrPaths.IsInvalid)
{
path.Dispose();
throw Interop.GetExceptionForIoErrno(Interop.Sys.GetLastErrorInfo(), _fullDirectory, true);
}
// Create the callback for the EventStream if it wasn't previously created for this instance.
if (_callback == null)
{
_callback = new Interop.EventStream.FSEventStreamCallback(FileSystemEventCallback);
}
// Make sure the OS file buffer(s) are fully flushed so we don't get events from cached I/O
Interop.Sys.Sync();
// Create the event stream for the path and tell the stream to watch for file system events.
_eventStream = Interop.EventStream.FSEventStreamCreate(
_callback,
arrPaths,
Interop.EventStream.kFSEventStreamEventIdSinceNow,
0.0f,
EventStreamFlags);
if (_eventStream.IsInvalid)
{
arrPaths.Dispose();
path.Dispose();
throw Interop.GetExceptionForIoErrno(Interop.Sys.GetLastErrorInfo(), _fullDirectory, true);
}
// Create and start our watcher thread then wait for the thread to initialize and start
// the RunLoop. We wait for that to prevent this function from returning before the RunLoop
// has a chance to start so that any callers won't race with the background thread's initialization
// and calling Stop, which would attempt to stop a RunLoop that hasn't started yet.
var runLoopStarted = new ManualResetEventSlim();
new Thread(WatchForFileSystemEventsThreadStart)
{
IsBackground = true
}.Start(runLoopStarted);
runLoopStarted.Wait();
}
internal static extern void FSEventStreamStop(SafeEventStreamHandle streamRef);
internal static extern void FSEventStreamUnscheduleFromRunLoop(
SafeEventStreamHandle streamRef,
CFRunLoopRef runLoop,
SafeCreateHandle runLoopMode);
internal static extern bool FSEventStreamStart(SafeEventStreamHandle streamRef);