add eventfd emulation to communicate receiver -> sender

1 files changed, 73 insertions, 0 deletions

diff --git a/src/event.c b/src/event.c
new file mode 100644
index 0000000..ed78835
--- /dev/null
+++ b/src/event.c
@@ -0,0 +1,73 @@
+/*
+ * (C) 2006-2007 by Pablo Neira Ayuso <pablo@netfilter.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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#include <unistd.h>
+#include <stdlib.h>
+
+#include "event.h"
+
+struct evfd {
+	int read;
+	int fds[2];
+};
+
+struct evfd *create_evfd(void)
+{
+	struct evfd *e;
+
+	e = calloc(1, sizeof(struct evfd));
+	if (e == NULL)
+		return NULL;
+
+	if (pipe(e->fds) == -1) {
+		free(e);
+		return NULL;
+	}
+
+	return e;
+}
+
+void destroy_evfd(struct evfd *e)
+{
+	close(e->fds[0]);
+	close(e->fds[1]);
+	free(e);
+}
+
+int get_read_evfd(struct evfd *evfd)
+{
+	return evfd->fds[0];
+}
+
+int write_evfd(struct evfd *evfd)
+{
+	int data = 0;
+
+	if (evfd->read)
+		return 0;
+
+	evfd->read = 1;
+	return write(evfd->fds[1], &data, sizeof(data));
+}
+
+int read_evfd(struct evfd *evfd)
+{
+	int data;
+
+	evfd->read = 0;
+	return read(evfd->fds[0], &data, sizeof(data));
+}