add libev to the distribution (latest CVS version)

libev/LICENSE

+All files in libev are Copyright (C)2007,2008,2009 Marc Alexander Lehmann.
+
+Redistribution and use in source and binary forms, with or without
+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.
+
+    * 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 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.
+
+Alternatively, the contents of this package may be used under the terms
+of the GNU General Public License ("GPL") version 2 or any later version,
+in which case the provisions of the GPL are applicable instead of the
+above. If you wish to allow the use of your version of this package only
+under the terms of the GPL and not to allow others to use your version of
+this file under the BSD license, indicate your decision by deleting the
+provisions above and replace them with the notice and other provisions
+required by the GPL in this and the other files of this package. If you do
+not delete the provisions above, a recipient may use your version of this
+file under either the BSD or the GPL.

libev/ev_poll.c

+/*
+ * libev poll fd activity backend
+ *
+ * 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
+ * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
+ * CIAL, 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 OTH-
+ * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * the GNU General Public License ("GPL") version 2 or any later version,
+ * in which case the provisions of the GPL are applicable instead of
+ * the above. If you wish to allow the use of your version of this file
+ * only under the terms of the GPL and not to allow others to use your
+ * version of this file under the BSD license, indicate your decision
+ * by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL. If you do not delete the
+ * provisions above, a recipient may use your version of this file under
+ * either the BSD or the GPL.
+ */
+
+#include <poll.h>
+
+void inline_size
+pollidx_init (int *base, int count)
+{
+  /* consider using memset (.., -1, ...), which is practically guaranteed
+   * to work on all systems implementing poll */
+  while (count--)
+    *base++ = -1;
+}
+
+static void
+poll_modify (EV_P_ int fd, int oev, int nev)
+{
+  int idx;
+
+  if (oev == nev)
+    return;
+
+  array_needsize (int, pollidxs, pollidxmax, fd + 1, pollidx_init);
+
+  idx = pollidxs [fd];
+
+  if (idx < 0) /* need to allocate a new pollfd */
+    {
+      pollidxs [fd] = idx = pollcnt++;
+      array_needsize (struct pollfd, polls, pollmax, pollcnt, EMPTY2);
+      polls [idx].fd = fd;
+    }
+
+  assert (polls [idx].fd == fd);
+
+  if (nev)
+    polls [idx].events =
+        (nev & EV_READ ? POLLIN : 0)
+        | (nev & EV_WRITE ? POLLOUT : 0);
+  else /* remove pollfd */
+    {
+      pollidxs [fd] = -1;
+
+      if (expect_true (idx < --pollcnt))
+        {
+          polls [idx] = polls [pollcnt];
+          pollidxs [polls [idx].fd] = idx;
+        }
+    }
+}
+
+static void
+poll_poll (EV_P_ ev_tstamp timeout)
+{
+  struct pollfd *p;
+  int res;
+  
+  EV_RELEASE_CB;
+  res = poll (polls, pollcnt, ev_timeout_to_ms (timeout));
+  EV_ACQUIRE_CB;
+
+  if (expect_false (res < 0))
+    {
+      if (errno == EBADF)
+        fd_ebadf (EV_A);
+      else if (errno == ENOMEM && !syserr_cb)
+        fd_enomem (EV_A);
+      else if (errno != EINTR)
+        ev_syserr ("(libev) poll");
+    }
+  else
+    for (p = polls; res; ++p)
+      {
+        assert (("libev: poll() returned illegal result, broken BSD kernel?", p < polls + pollcnt));
+
+        if (expect_false (p->revents)) /* this expect is debatable */
+          {
+            --res;
+
+            if (expect_false (p->revents & POLLNVAL))
+              fd_kill (EV_A_ p->fd);
+            else
+              fd_event (
+                EV_A_
+                p->fd,
+                (p->revents & (POLLOUT | POLLERR | POLLHUP) ? EV_WRITE : 0)
+                | (p->revents & (POLLIN | POLLERR | POLLHUP) ? EV_READ : 0)
+              );
+          }
+      }
+}
+
+int inline_size
+poll_init (EV_P_ int flags)
+{
+  backend_fudge  = 0.; /* posix says this is zero */
+  backend_modify = poll_modify;
+  backend_poll   = poll_poll;
+
+  pollidxs = 0; pollidxmax = 0;
+  polls    = 0; pollmax    = 0; pollcnt = 0;
+
+  return EVBACKEND_POLL;
+}
+
+void inline_size
+poll_destroy (EV_P)
+{
+  ev_free (pollidxs);
+  ev_free (polls);
+}
+