configure.ac: add option --enable-eventfd

Remove the runtime check for eventfd(), hard-code the feature once
it's been selected at compile time.  The class WakeFD is splitted into
EventFD and EventPipe, using WakeFD as a macro diversion.

1 files changed, 72 insertions, 0 deletions

diff --git a/src/event/EventFD.cxx b/src/event/EventFD.cxx
new file mode 100644
index 000000000..f103c44b8
--- /dev/null
+++ b/src/event/EventFD.cxx
@@ -0,0 +1,72 @@
+/*
+ * Copyright (C) 2003-2013 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "config.h"
+#ifdef USE_EVENTFD
+#include "EventFD.hxx"
+#include "fd_util.h"
+#include "gcc.h"
+
+#include <unistd.h>
+
+#include <sys/eventfd.h>
+
+#ifdef WIN32
+static bool PoorSocketPair(int fd[2]);
+#endif
+
+bool
+EventFD::Create()
+{
+	assert(fd == -1);
+
+	fd = eventfd_cloexec_nonblock(0, 0);
+	return fd >= 0;
+}
+
+void
+EventFD::Destroy()
+{
+	close(fd);
+
+#ifndef NDEBUG
+	fd = -1;
+#endif
+}
+
+bool
+EventFD::Read()
+{
+	assert(fd >= 0);
+
+	eventfd_t value;
+	return read(fd, &value, sizeof(value)) == (ssize_t)sizeof(value);
+}
+
+void
+EventFD::Write()
+{
+	assert(fd >= 0);
+
+	static constexpr eventfd_t value = 1;
+	gcc_unused ssize_t nbytes =
+		write(fd, &value, sizeof(value));
+}
+
+#endif /* USE_EVENTFD */