Enable socket keepalives.

adsbus/socket.c

@@ -0,0 +1,24 @@
+#include <assert.h>
+#include <errno.h>
+#include <netinet/in.h>
+#include <netinet/tcp.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+
+#include "socket.h"
+
+void socket_init(int fd) {
+	int optval = 1;
+	int err = setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, &optval, sizeof(optval));
+	if (err == -1 && errno == ENOTSOCK) {
+		return;
+	}
+	assert(!err);
+
+	optval = 30;
+	assert(!setsockopt(fd, IPPROTO_TCP, TCP_KEEPIDLE, &optval, sizeof(optval)));
+	optval = 10;
+	assert(!setsockopt(fd, IPPROTO_TCP, TCP_KEEPINTVL, &optval, sizeof(optval)));
+	optval = 3;
+	assert(!setsockopt(fd, IPPROTO_TCP, TCP_KEEPCNT, &optval, sizeof(optval)));
+}