1 files changed, 207 insertions, 0 deletions
diff --git a/powerline/lib/watcher/uv.py b/powerline/lib/watcher/uv.py
new file mode 100644
index 0000000..272db0f
--- /dev/null
+++ b/powerline/lib/watcher/uv.py
@@ -0,0 +1,207 @@
+# vim:fileencoding=utf-8:noet
+from __future__ import (unicode_literals, division, absolute_import, print_function)
+
+import os
+
+from collections import defaultdict
+from threading import RLock
+from functools import partial
+from threading import Thread
+from errno import ENOENT
+
+from powerline.lib.path import realpath
+from powerline.lib.encoding import get_preferred_file_name_encoding
+
+
+class UvNotFound(NotImplementedError):
+	pass
+
+
+pyuv = None
+pyuv_version_info = None
+
+
+def import_pyuv():
+	global pyuv
+	global pyuv_version_info
+	if not pyuv:
+		try:
+			pyuv = __import__('pyuv')
+		except ImportError:
+			raise UvNotFound
+		else:
+			pyuv_version_info = tuple((int(c) for c in pyuv.__version__.split('.')))
+
+
+class UvThread(Thread):
+	daemon = True
+
+	def __init__(self, loop):
+		self.uv_loop = loop
+		self.async_handle = pyuv.Async(loop, self._async_cb)
+		super(UvThread, self).__init__()
+
+	def _async_cb(self, handle):
+		self.uv_loop.stop()
+		self.async_handle.close()
+
+	def run(self):
+		self.uv_loop.run()
+
+	def join(self):
+		self.async_handle.send()
+		return super(UvThread, self).join()
+
+
+_uv_thread = None
+
+
+def start_uv_thread():
+	global _uv_thread
+	if _uv_thread is None:
+		loop = pyuv.Loop()
+		_uv_thread = UvThread(loop)
+		_uv_thread.start()
+	return _uv_thread.uv_loop
+
+
+def normpath(path, fenc):
+	path = realpath(path)
+	if isinstance(path, bytes):
+		return path.decode(fenc)
+	else:
+		return path
+
+
+class UvWatcher(object):
+	def __init__(self):
+		import_pyuv()
+		self.watches = {}
+		self.lock = RLock()
+		self.loop = start_uv_thread()
+		self.fenc = get_preferred_file_name_encoding()
+		if pyuv_version_info >= (1, 0):
+			self._start_watch = self._start_watch_1_x
+		else:
+			self._start_watch = self._start_watch_0_x
+
+	def _start_watch_1_x(self, path):
+		handle = pyuv.fs.FSEvent(self.loop)
+		handle.start(path, 0, partial(self._record_event, path))
+		self.watches[path] = handle
+
+	def _start_watch_0_x(self, path):
+		self.watches[path] = pyuv.fs.FSEvent(
+			self.loop,
+			path,
+			partial(self._record_event, path),
+			pyuv.fs.UV_CHANGE | pyuv.fs.UV_RENAME
+		)
+
+	def watch(self, path):
+		path = normpath(path, self.fenc)
+		with self.lock:
+			if path not in self.watches:
+				try:
+					self._start_watch(path)
+				except pyuv.error.FSEventError as e:
+					code = e.args[0]
+					if code == pyuv.errno.UV_ENOENT:
+						raise OSError(ENOENT, 'No such file or directory: ' + path)
+					else:
+						raise
+
+	def unwatch(self, path):
+		path = normpath(path, self.fenc)
+		with self.lock:
+			try:
+				watch = self.watches.pop(path)
+			except KeyError:
+				return
+		watch.close(partial(self._stopped_watching, path))
+
+	def is_watching(self, path):
+		with self.lock:
+			return normpath(path, self.fenc) in self.watches
+
+	def __del__(self):
+		try:
+			lock = self.lock
+		except AttributeError:
+			pass
+		else:
+			with lock:
+				while self.watches:
+					path, watch = self.watches.popitem()
+					watch.close(partial(self._stopped_watching, path))
+
+
+class UvFileWatcher(UvWatcher):
+	def __init__(self):
+		super(UvFileWatcher, self).__init__()
+		self.events = defaultdict(list)
+
+	def _record_event(self, path, fsevent_handle, filename, events, error):
+		with self.lock:
+			self.events[path].append(events)
+			if events | pyuv.fs.UV_RENAME:
+				if not os.path.exists(path):
+					self.watches.pop(path).close()
+
+	def _stopped_watching(self, path, *args):
+		self.events.pop(path, None)
+
+	def __call__(self, path):
+		path = normpath(path, self.fenc)
+		with self.lock:
+			events = self.events.pop(path, None)
+		if events:
+			return True
+		if path not in self.watches:
+			self.watch(path)
+			return True
+		return False
+
+
+class UvTreeWatcher(UvWatcher):
+	is_dummy = False
+
+	def __init__(self, basedir, ignore_event=None):
+		super(UvTreeWatcher, self).__init__()
+		self.ignore_event = ignore_event or (lambda path, name: False)
+		self.basedir = normpath(basedir, self.fenc)
+		self.modified = True
+		self.watch_directory(self.basedir)
+
+	def watch_directory(self, path):
+		for root, dirs, files in os.walk(normpath(path, self.fenc)):
+			self.watch_one_directory(root)
+
+	def watch_one_directory(self, dirname):
+		try:
+			self.watch(dirname)
+		except OSError:
+			pass
+
+	def _stopped_watching(self, path, *args):
+		pass
+
+	def _record_event(self, path, fsevent_handle, filename, events, error):
+		if not self.ignore_event(path, filename):
+			self.modified = True
+			if events == pyuv.fs.UV_CHANGE | pyuv.fs.UV_RENAME:
+				# Stat changes to watched directory are UV_CHANGE|UV_RENAME. It 
+				# is weird.
+				pass
+			elif events | pyuv.fs.UV_RENAME:
+				if not os.path.isdir(path):
+					self.unwatch(path)
+				else:
+					full_name = os.path.join(path, filename)
+					if os.path.isdir(full_name):
+						# For some reason mkdir and rmdir both fall into this 
+						# category
+						self.watch_directory(full_name)
+
+	def __call__(self):
+		return self.__dict__.pop('modified', False)