1 files changed, 90 insertions, 0 deletions
diff --git a/powerline/lib/watcher/tree.py b/powerline/lib/watcher/tree.py
new file mode 100644
index 0000000..7d2b83f
--- /dev/null
+++ b/powerline/lib/watcher/tree.py
@@ -0,0 +1,90 @@
+# vim:fileencoding=utf-8:noet
+from __future__ import (unicode_literals, division, absolute_import, print_function)
+
+import sys
+
+from powerline.lib.monotonic import monotonic
+from powerline.lib.inotify import INotifyError
+from powerline.lib.path import realpath
+from powerline.lib.watcher.inotify import INotifyTreeWatcher, DirTooLarge, NoSuchDir, BaseDirChanged
+from powerline.lib.watcher.uv import UvTreeWatcher, UvNotFound
+
+
+class DummyTreeWatcher(object):
+	is_dummy = True
+
+	def __init__(self, basedir):
+		self.basedir = realpath(basedir)
+
+	def __call__(self):
+		return False
+
+
+class TreeWatcher(object):
+	def __init__(self, pl, watcher_type, expire_time):
+		self.watches = {}
+		self.last_query_times = {}
+		self.expire_time = expire_time * 60
+		self.pl = pl
+		self.watcher_type = watcher_type
+
+	def get_watcher(self, path, ignore_event):
+		if self.watcher_type == 'inotify':
+			return INotifyTreeWatcher(path, ignore_event=ignore_event)
+		if self.watcher_type == 'uv':
+			return UvTreeWatcher(path, ignore_event=ignore_event)
+		if self.watcher_type == 'dummy':
+			return DummyTreeWatcher(path)
+		# FIXME
+		if self.watcher_type == 'stat':
+			return DummyTreeWatcher(path)
+		if self.watcher_type == 'auto':
+			if sys.platform.startswith('linux'):
+				try:
+					return INotifyTreeWatcher(path, ignore_event=ignore_event)
+				except (INotifyError, DirTooLarge) as e:
+					if not isinstance(e, INotifyError):
+						self.pl.warn('Failed to watch path: {0} with error: {1}'.format(path, e))
+			try:
+				return UvTreeWatcher(path, ignore_event=ignore_event)
+			except UvNotFound:
+				pass
+			return DummyTreeWatcher(path)
+		else:
+			raise ValueError('Unknown watcher type: {0}'.format(self.watcher_type))
+
+	def watch(self, path, ignore_event=None):
+		path = realpath(path)
+		w = self.get_watcher(path, ignore_event)
+		self.watches[path] = w
+		return w
+
+	def expire_old_queries(self):
+		pop = []
+		now = monotonic()
+		for path, lt in self.last_query_times.items():
+			if now - lt > self.expire_time:
+				pop.append(path)
+		for path in pop:
+			del self.last_query_times[path]
+
+	def __call__(self, path, ignore_event=None):
+		path = realpath(path)
+		self.expire_old_queries()
+		self.last_query_times[path] = monotonic()
+		w = self.watches.get(path, None)
+		if w is None:
+			try:
+				self.watch(path, ignore_event=ignore_event)
+			except NoSuchDir:
+				pass
+			return True
+		try:
+			return w()
+		except BaseDirChanged:
+			self.watches.pop(path, None)
+			return True
+		except DirTooLarge as e:
+			self.pl.warn(str(e))
+			self.watches[path] = DummyTreeWatcher(path)
+			return False