Add help messages and command listing to dispatcher handlers.

[software/pymin.git] / eventloop.py

diff --git a/eventloop.py b/eventloop.py
index 7da492db90de7387c1fae3c48d962d2648a69df2..932e1b802d3709f82364f977a30ea9fe741d665f 100644 (file)
--- a/eventloop.py
+++ b/eventloop.py
@@ -6,10 +6,35 @@ A simple event loop.
 Please see EventLoop class documentation for more info.
 """
 
-from select import poll, POLLIN, POLLPRI, POLLERR
+import select
+from select import POLLIN, POLLPRI, POLLERR
 
 __ALL__ = ('EventLoop')
 
+class LoopInterruptedError(RuntimeError):
+    r"""
+    LoopInterruptedError(select_error) -> LoopInterruptedError instance.
+
+    This class is raised when the event loop is interrupted in an unexpected
+    way. It wraps a select error, which can be accessed using the 'select_error'
+    attribute.
+    """
+
+    def __init__(self, select_error):
+        r"""Initialize the object.
+
+        See the class documentation for more info.
+        """
+        self.select_error = select_error
+
+    def __repr__(self):
+        r"repr(obj) -> Object representation."
+        return 'LoopInterruptedError(select_error=%r)' % self.select_error
+
+    def __str__(self):
+        r"str(obj) -> String representation."
+        return 'Loop interrupted: %s' % self.select_error
+
 class EventLoop:
     r"""EventLoop(file[, handler]) -> EventLoop instance
 
@@ -53,7 +78,7 @@ class EventLoop:
 
         See EventLoop class documentation for more info.
         """
-        self.poll = poll()
+        self.poll = select.poll()
         self._stop = False
         self.__register(file)
         self.handler = handler
@@ -101,7 +126,10 @@ class EventLoop:
         then only 1 event is processed and then this method returns.
         """
         while True:
-            res = self.poll.poll()
+            try:
+                res = self.poll.poll()
+            except select.error, e:
+                raise LoopInterruptedError(e)
             if self.handler is not None:
                 self.handler(self)
             else: