remove libevent code (a comment and the kevent test) from ev_kqueue and relicense under libev license

ev_kqueue.c

@@ -1,30 +1,32 @@
 /*
- * Copyright 2007      Marc Alexander Lehmann <libev@schmorp.de>
- * Copyright 2000-2002 Niels Provos <provos@citi.umich.edu>
+ * libev kqueue backend
+ *
+ * Copyright (c) 2007 Marc Alexander Lehmann <libev@schmorp.de>
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
  *
- * 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.
- * 3. The name of the author may not be used to endorse or promote products
- *    derived from this software without specific prior written permission.
+ *     * 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 MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
- * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
- * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include <sys/types.h>
@@ -106,16 +108,6 @@ kqueue_poll (EV_P_ ev_tstamp timeout)
         {
 	  int err = kqueue_events [i].data;
 
-          /* 
-           * errors that may happen
-           *   EBADF happens when the file discriptor has been
-           *   closed,
-           *   ENOENT when the file descriptor was closed and
-           *   then reopened.
-           *   EINVAL for some reasons not understood; EINVAL
-           *   should not be returned ever; but FreeBSD does :-\
-           */
-
           /* we are only interested in errors for fds that we are interested in :) */
           if (anfds [fd].events)
 	    {
@@ -161,30 +153,12 @@ kqueue_init (EV_P_ int flags)
 
   fcntl (backend_fd, F_SETFD, FD_CLOEXEC); /* not sure if necessary, hopefully doesn't hurt */
 
-  /* Check for Mac OS X kqueue bug. */
-  ch.ident  = -1;
-  ch.filter = EVFILT_READ;
-  ch.flags  = EV_ADD;
-
-  /* 
-   * If kqueue works, then kevent will succeed, and it will
-   * stick an error in ev. If kqueue is broken, then
-   * kevent will fail.
-   */
-  if (kevent (backend_fd, &ch, 1, &ev, 1, 0) != 1
-      || ev.ident != -1
-      || ev.flags != EV_ERROR)
-    {
-      /* detected broken kqueue */
-      close (backend_fd);
-      return 0;
-    }
-
+  /* fudge *might* be zero from the documentation, but bsd docs are notoriously wrong */
   backend_fudge  = 1e-3; /* needed to compensate for kevent returning early */
   backend_modify = kqueue_modify;
   backend_poll   = kqueue_poll;
 
-  kqueue_eventmax = 64; /* intiial number of events receivable per poll */
+  kqueue_eventmax = 64; /* initial number of events receivable per poll */
   kqueue_events = (struct kevent *)ev_malloc (sizeof (struct kevent) * kqueue_eventmax);
 
   kqueue_changes   = 0;