--- libev/ev_epoll.c	2010/10/22 10:50:24	1.54
+++ libev/ev_epoll.c	2011/02/16 08:02:50	1.60
@@ -1,19 +1,19 @@
 /*
  * libev epoll fd activity backend
  *
- * Copyright (c) 2007,2008,2009,2010 Marc Alexander Lehmann <libev@schmorp.de>
+ * Copyright (c) 2007,2008,2009,2010,2011 Marc Alexander Lehmann <libev@schmorp.de>
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without modifica-
  * tion, are permitted provided that the following conditions are met:
- * 
+ *
  *   1.  Redistributions of source code must retain the above copyright notice,
  *       this list of conditions and the following disclaimer.
- * 
+ *
  *   2.  Redistributions in binary form must reproduce the above copyright
  *       notice, this list of conditions and the following disclaimer in the
  *       documentation and/or other materials provided with the distribution.
- * 
+ *
  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
  * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
@@ -53,7 +53,8 @@
  *    (such as files). while not critical, no other advanced interface
  *    seems to share this (rather non-unixy) limitation.
  * e) epoll claims to be embeddable, but in practise you never get
- *    a ready event for the epoll fd.
+ *    a ready event for the epoll fd (broken: <=2.6.26, working: >=2.6.32).
+ * f) epoll_ctl returning EPERM means the fd is always ready.
  *
  * lots of "weird code" and complication handling in this file is due
  * to these design problems with epoll, as we try very hard to avoid
@@ -64,6 +65,8 @@
 
 #include <sys/epoll.h>
 
+#define EV_EMASK_EPERM 0x80
+
 static void
 epoll_modify (EV_P_ int fd, int oev, int nev)
 {
@@ -112,6 +115,21 @@
       if (!epoll_ctl (backend_fd, EPOLL_CTL_MOD, fd, &ev))
         return;
     }
+  else if (expect_true (errno == EPERM))
+    {
+      /* EPERM means the fd is always ready, but epoll is too snobbish */
+      /* to handle it, unlike select or poll. */
+      anfds [fd].emask = EV_EMASK_EPERM;
+
+      /* add fd to epoll_eperms, if not already inside */
+      if (!(oldmask & EV_EMASK_EPERM))
+        {
+          array_needsize (int, epoll_eperms, epoll_epermmax, epoll_epermcnt + 1, EMPTY2);
+          epoll_eperms [epoll_epermcnt++] = fd;
+        }
+
+      return;
+    }
 
   fd_kill (EV_A_ fd);
 
@@ -125,11 +143,12 @@
 {
   int i;
   int eventcnt;
-  
+
   /* epoll wait times cannot be larger than (LONG_MAX - 999UL) / HZ msecs, which is below */
   /* the default libev max wait time, however. */
   EV_RELEASE_CB;
-  eventcnt = epoll_wait (backend_fd, epoll_events, epoll_eventmax, (int)ceil (timeout * 1000.));
+  eventcnt = epoll_wait (backend_fd, epoll_events, epoll_eventmax,
+                         epoll_epermcnt ? 0 : ev_timeout_to_ms (timeout));
   EV_ACQUIRE_CB;
 
   if (expect_false (eventcnt < 0))
@@ -186,6 +205,18 @@
       epoll_eventmax = array_nextsize (sizeof (struct epoll_event), epoll_eventmax, epoll_eventmax + 1);
       epoll_events = (struct epoll_event *)ev_malloc (sizeof (struct epoll_event) * epoll_eventmax);
     }
+
+  /* now synthesize events for all fds where epoll fails, while select works... */
+  for (i = epoll_epermcnt; i--; )
+    {
+      int fd = epoll_eperms [i];
+      unsigned char events = anfds [fd].events & (EV_READ | EV_WRITE);
+
+      if (anfds [fd].emask & EV_EMASK_EPERM && events)
+        fd_event (EV_A_ fd, events);
+      else
+        epoll_eperms [i] = epoll_eperms [--epoll_epermcnt];
+    }
 }
 
 int inline_size
@@ -217,6 +248,7 @@
 epoll_destroy (EV_P)
 {
   ev_free (epoll_events);
+  array_free (epoll_eperm, EMPTY);
 }
 
 void inline_size