From 3b486fc4f8081355fc0b87ebbf6c261692d7a418 Mon Sep 17 00:00:00 2001
From: Imre SZEBENYI <szeim@elte.hu>
Date: Wed, 27 Oct 2010 13:34:47 +0200
Subject: [PATCH] Fixed IOStream._handle_events (try/except block)

Fixed IOStream._handle_events (try/except block) to prevent
infinite loop when an unhandled exception occurs
---
 tornado/iostream.py | 46 +++++++++++++++++++++++++--------------------
 1 file changed, 26 insertions(+), 20 deletions(-)

diff --git a/tornado/iostream.py b/tornado/iostream.py
index 9482330a..4a487593 100644
--- a/tornado/iostream.py
+++ b/tornado/iostream.py
@@ -189,27 +189,33 @@ class IOStream(object):
         if not self.socket:
             logging.warning("Got events for closed stream %d", fd)
             return
-        if events & self.io_loop.READ:
-            self._handle_read()
-        if not self.socket:
-            return
-        if events & self.io_loop.WRITE:
-            if self._connecting:
-                self._handle_connect()
-            self._handle_write()
-        if not self.socket:
-            return
-        if events & self.io_loop.ERROR:
+        try:
+            if events & self.io_loop.READ:
+                self._handle_read()
+            if not self.socket:
+                return
+            if events & self.io_loop.WRITE:
+                if self._connecting:
+                    self._handle_connect()
+                self._handle_write()
+            if not self.socket:
+                return
+            if events & self.io_loop.ERROR:
+                self.close()
+                return
+            state = self.io_loop.ERROR
+            if self._read_delimiter or self._read_bytes:
+                state |= self.io_loop.READ
+            if self._write_buffer:
+                state |= self.io_loop.WRITE
+            if state != self._state:
+                self._state = state
+                self.io_loop.update_handler(self.socket.fileno(), self._state)
+        except:
+            logging.error("Uncaught exception, closing connection.",
+                          exc_info=True)
             self.close()
-            return
-        state = self.io_loop.ERROR
-        if self._read_delimiter or self._read_bytes:
-            state |= self.io_loop.READ
-        if self._write_buffer:
-            state |= self.io_loop.WRITE
-        if state != self._state:
-            self._state = state
-            self.io_loop.update_handler(self.socket.fileno(), self._state)
+            raise
 
     def _run_callback(self, callback, *args, **kwargs):
         try: