--- libev/ev_select.c	2008/05/26 04:14:32	1.33
+++ libev/ev_select.c	2009/01/07 17:54:57	1.41
@@ -1,7 +1,7 @@
 /*
  * libev select fd activity backend
  *
- * Copyright (c) 2007,2008 Marc Alexander Lehmann <libev@schmorp.de>
+ * Copyright (c) 2007,2008,2009 Marc Alexander Lehmann <libev@schmorp.de>
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without modifica-
@@ -54,6 +54,8 @@
 #if EV_SELECT_IS_WINSOCKET
 # undef EV_SELECT_USE_FD_SET
 # define EV_SELECT_USE_FD_SET 1
+# undef NFDBITS
+# define NFDBITS 0
 #endif
 
 #if !EV_SELECT_USE_FD_SET
@@ -70,22 +72,32 @@
 
   {
 #if EV_SELECT_USE_FD_SET
-
     #if EV_SELECT_IS_WINSOCKET
     SOCKET handle = anfds [fd].handle;
     #else
     int handle = fd;
     #endif
 
-    if (nev & EV_READ)
-      FD_SET (handle, (fd_set *)vec_ri);
-    else
-      FD_CLR (handle, (fd_set *)vec_ri);
-
-    if (nev & EV_WRITE)
-      FD_SET (handle, (fd_set *)vec_wi);
-    else
-      FD_CLR (handle, (fd_set *)vec_wi);
+    assert (("libev: fd >= FD_SETSIZE passed to fd_set-based select backend", fd < FD_SETSIZE));
+
+    /* FD_SET is broken on windows (it adds the fd to a set twice or more,
+     * which eventually leads to overflows). Need to call it only on changes.
+     */
+    #if EV_SELECT_IS_WINSOCKET
+    if ((oev ^ nev) & EV_READ)
+    #endif
+      if (nev & EV_READ)
+        FD_SET (handle, (fd_set *)vec_ri);
+      else
+        FD_CLR (handle, (fd_set *)vec_ri);
+
+    #if EV_SELECT_IS_WINSOCKET
+    if ((oev ^ nev) & EV_WRITE)
+    #endif
+      if (nev & EV_WRITE)
+        FD_SET (handle, (fd_set *)vec_wi);
+      else
+        FD_CLR (handle, (fd_set *)vec_wi);
 
 #else
 
@@ -147,6 +159,9 @@
    */
   memcpy (vec_eo, vec_wi, fd_setsize);
   res = select (vec_max * NFDBITS, (fd_set *)vec_ro, (fd_set *)vec_wo, (fd_set *)vec_eo, &tv);
+#elif EV_SELECT_USE_FD_SET
+  fd_setsize = anfdmax < FD_SETSIZE ? anfdmax : FD_SETSIZE;
+  res = select (fd_setsize, (fd_set *)vec_ro, (fd_set *)vec_wo, 0, &tv);
 #else
   res = select (vec_max * NFDBITS, (fd_set *)vec_ro, (fd_set *)vec_wo, 0, &tv);
 #endif
@@ -168,7 +183,7 @@
       #ifdef _WIN32
       /* select on windows errornously returns EINVAL when no fd sets have been
        * provided (this is documented). what microsoft doesn't tell you that this bug
-       * exists even when the fd sets are provided, so we have to check for this bug
+       * exists even when the fd sets _are_ provided, so we have to check for this bug
        * here and emulate by sleeping manually.
        * we also get EINVAL when the timeout is invalid, but we ignore this case here
        * and assume that EINVAL always means: you have to wait manually.
@@ -185,7 +200,7 @@
       else if (errno == ENOMEM && !syserr_cb)
         fd_enomem (EV_A);
       else if (errno != EINTR)
-        syserr ("(libev) select");
+        ev_syserr ("(libev) select");
 
       return;
     }
@@ -254,7 +269,6 @@
   backend_poll   = select_poll;
 
 #if EV_SELECT_USE_FD_SET
-  vec_max = FD_SETSIZE / 32;
   vec_ri  = ev_malloc (sizeof (fd_set)); FD_ZERO ((fd_set *)vec_ri);
   vec_ro  = ev_malloc (sizeof (fd_set));
   vec_wi  = ev_malloc (sizeof (fd_set)); FD_ZERO ((fd_set *)vec_wi);