event/EPollFD: basic support for Linux epoll

1 files changed, 80 insertions, 0 deletions

diff --git a/src/system/EPollFD.hxx b/src/system/EPollFD.hxx
new file mode 100644
index 000000000..1ebacfeae
--- /dev/null
+++ b/src/system/EPollFD.hxx
@@ -0,0 +1,80 @@
+/*
+ * 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.
+ */
+
+#ifndef MPD_EPOLL_FD_HXX
+#define MPD_EPOLL_FD_HXX
+
+#include <assert.h>
+#include <sys/epoll.h>
+#include <unistd.h>
+
+#include "check.h"
+
+struct epoll_event;
+
+/**
+ * A class that wraps Linux epoll.
+ *
+ * Errors in the constructor are fatal.
+ */
+class EPollFD {
+	const int fd;
+
+public:
+	EPollFD();
+
+	~EPollFD() {
+		assert(fd >= 0);
+
+		::close(fd);
+	}
+
+	EPollFD(const EPollFD &other) = delete;
+	EPollFD &operator=(const EPollFD &other) = delete;
+
+	int Wait(epoll_event *events, int maxevents, int timeout) {
+		return ::epoll_wait(fd, events, maxevents, timeout);
+	}
+
+	bool Control(int op, int _fd, epoll_event *event) {
+		return ::epoll_ctl(fd, op, _fd, event) >= 0;
+	}
+
+	bool Add(int _fd, uint32_t events, void *ptr) {
+		epoll_event e;
+		e.events = events;
+		e.data.ptr = ptr;
+
+		return Control(EPOLL_CTL_DEL, _fd, &e);
+	}
+
+	bool Modify(int _fd, uint32_t events, void *ptr) {
+		epoll_event e;
+		e.events = events;
+		e.data.ptr = ptr;
+
+		return Control(EPOLL_CTL_MOD, _fd, &e);
+	}
+
+	bool Remove(int _fd) {
+		return Control(EPOLL_CTL_DEL, _fd, nullptr);
+	}
+};
+
+#endif