X-Git-Url: http://git.itanic.dy.fi/?p=log-plotter;a=blobdiff_plain;f=event.c;fp=event.c;h=b3cbaf25ca4529cc0aa03b0eb60212b121616a37;hp=0000000000000000000000000000000000000000;hb=9abf935040bd368c4b3c1828a79691d200fd45a9;hpb=4daad2abbacb183bc39d7ef1220e86afe6068b5d

diff --git a/event.c b/event.c
new file mode 100644
index 0000000..b3cbaf2
--- /dev/null
+++ b/event.c
@@ -0,0 +1,98 @@
+#include <errno.h>
+#include <sys/epoll.h>
+
+#include "event.h"
+#include "trace.h"
+
+static int epoll_fd = -1;
+
+static int init_event_handler(void)
+{
+	epoll_fd = epoll_create(1);
+	if (epoll_fd < 0) {
+		pr_err("Failed to create epoll socket: %m\n");
+		return -1;
+	}
+
+	return 0;
+}
+
+int register_event_handler(struct eventhandler_entry *handler)
+{
+	struct epoll_event ev;
+	int ret = 0;
+
+	if (epoll_fd < 0)
+		ret = init_event_handler();
+
+	if (ret < 0)
+		return ret;
+
+	if (handler->fd < 0) {
+		pr_err("Invalid file descriptor of %d for handler %s\n",
+			handler->fd, handler->name);
+		return -1;
+	}
+
+	if (!handler->handle_event) {
+		pr_err("Handler %s missing callback function\n", handler->name);
+		return -1;
+	}
+
+	pr_debug("Registering handler for \"%s\", fd=%d\n",
+		handler->name, handler->fd);
+
+	ev.data.fd = handler->fd;
+	ev.data.ptr = handler;
+	ev.events = handler->events;
+	ret = epoll_ctl(epoll_fd, EPOLL_CTL_ADD, handler->fd, &ev);
+	if (ret) {
+		pr_err("Failed to add epoll_fd: %m\n");
+		return -1;
+	}
+
+	return 0;
+}
+
+int poll_events(int timeout_ms)
+{
+	struct epoll_event event;
+	struct eventhandler_entry *handler;
+	int ret;
+
+	ret = epoll_wait(epoll_fd, &event, 1, timeout_ms);
+
+	if (ret == -1) {
+		if (errno != EINTR) {
+			pr_err("epoll_wait: %m\n");
+			return -1;
+		}
+
+		/*
+		 * If epoll_wait() was interrupted, better start
+		 * everything again from the beginning
+		 */
+		return 0;
+	}
+
+	if (ret == 0) {
+		pr_info("Timed out\n");
+		goto out;
+	}
+
+	handler = event.data.ptr;
+
+	if (!handler || !handler->handle_event) {
+		pr_err("Corrupted event handler for fd %d\n",
+			event.data.fd);
+		goto out;
+	}
+
+	pr_debug("Running handler %s to handle events from fd %d\n",
+		handler->name, handler->fd);
+	handler->handle_event(handler);
+
+out:
+	return ret;
+}
+