zdtm: Add utsname.c source code

I occasionally droppped this file but it's
a part of commit

dcd64e9d

So add it back.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>

test/zdtm/live/static/utsname.c

+#include <string.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/utsname.h>
+
+#include "zdtmtst.h"
+
+const char *test_doc	= "Check that utsname hasn't changed";
+const char *test_author	= "Pavel Emelianov <xemul@parallels.com>";
+
+static struct utsname after;
+
+#define ZDTM_NODE "zdtm.nodename.ru"
+#define ZDTM_DOMAIN "zdtm.nodename.ru"
+
+static void test_fn(void)
+{
+	int ret;
+	int fd;
+
+	fd = open("/proc/sys/kernel/hostname", O_WRONLY);
+	if (fd < 0) {
+		err("Can't open hostname\n");
+		return;
+	}
+
+	ret = write(fd, ZDTM_NODE, sizeof(ZDTM_NODE));
+	if (ret != sizeof(ZDTM_NODE)) {
+		err("Can't write nodename\n");
+		return;
+	}
+
+	close(fd);
+
+	fd = open("/proc/sys/kernel/domainname", O_WRONLY);
+	if (fd < 0) {
+		err("Can't open domainname\n");
+		return;
+	}
+
+	ret = write(fd, ZDTM_DOMAIN, sizeof(ZDTM_DOMAIN));
+	if (ret != sizeof(ZDTM_DOMAIN)) {
+		err("Can't write domainname\n");
+		return;
+	}
+
+	close(fd);
+
+	test_daemon();
+	test_waitsig();
+
+	uname(&after);
+
+	ret = 1;
+
+	if (strcmp(ZDTM_NODE, after.nodename)) {
+		ret = 0;
+		fail("Nodename doesn't match");
+	}
+	if (strcmp(ZDTM_DOMAIN, after.__domainname)) {
+		ret = 0;
+		fail("Domainname doesn't match");
+	}
+
+	if (ret)
+		pass();
+}
+
+int main(int argc, char **argv)
+{
+	test_init_ns(argc, argv, CLONE_NEWUTS, test_fn);
+	return -1;
+}