tests: add a (failing) test for standalone unix sockets

v2: open two sockets, one "on top" of the other
v3: also drop unnecessary unlink(), we can just rely on rename()
Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

test/zdtm/.gitignore

@@ -28,6 +28,7 @@
 /static/cwd01
 /static/cwd02
 /static/deleted_dev
+/static/deleted_standalone_unix
 /static/deleted_unix_sock
 /static/different_creds
 /static/dumpable01

test/zdtm/static/Makefile

@@ -244,6 +244,7 @@ TST_DIR		=				\
 		unlink_regular00		\
 		mnt_enablefs			\
 		autofs				\
+		deleted_standalone_unix		\
 
 TST_DIR_FILE	=				\
 		chroot				\

test/zdtm/static/deleted_standalone_unix.c

+#define _GNU_SOURCE
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <sys/stat.h>
+#include <stdbool.h>
+#include <limits.h>
+
+#include "zdtmtst.h"
+
+const char *test_doc	= "Check that deleted unix sockets are restored correctly";
+const char *test_author	= "Tycho Andersen <tycho.andersen@canonical.com>";
+
+char *dirname;
+TEST_OPTION(dirname, string, "directory name", 1);
+
+static int fill_sock_name(struct sockaddr_un *name, const char *filename)
+{
+	char *cwd;
+
+	cwd = get_current_dir_name();
+	if (strlen(filename) + strlen(cwd) + 1 >= sizeof(name->sun_path))
+		return -1;
+
+	name->sun_family = AF_LOCAL;
+	sprintf(name->sun_path, "%s/%s", cwd, filename);
+	return 0;
+}
+
+static int bind_and_listen(struct sockaddr_un *addr)
+{
+	int sk;
+
+	sk = socket(PF_UNIX, SOCK_STREAM, 0);
+	if (sk < 0) {
+		fail("socket");
+		return -1;
+	}
+
+	if (bind(sk, addr, sizeof(*addr))) {
+		fail("bind %s", addr->sun_path);
+		close(sk);
+		return -1;
+	}
+
+	if (listen(sk, 1)) {
+		fail("listen");
+		close(sk);
+		return -1;
+	}
+
+	return sk;
+}
+
+int main(int argc, char **argv)
+{
+	struct sockaddr_un addr;
+	int sk1 = -1, sk2 = -1, ret = 1;
+	struct stat sb;
+	char filename[PATH_MAX], temp[PATH_MAX];
+
+	test_init(argc, argv);
+
+	sprintf(filename, "%s/sock", dirname);
+	sprintf(temp, "%s/temp", dirname);
+
+	if (mkdir(dirname, 0755) < 0) {
+		fail("mkdir");
+		goto out;
+	}
+
+	if (fill_sock_name(&addr, filename) < 0) {
+		pr_err("filename \"%s\" is too long", filename);
+		goto out;
+	}
+
+	sk1 = bind_and_listen(&addr);
+	if (sk1 < 0)
+		goto out;
+
+	if (rename(filename, temp) < 0) {
+		fail("rename");
+		goto out;
+	}
+
+	sk2 = bind_and_listen(&addr);
+	if (sk2 < 0)
+		goto out;
+
+	if (rename(temp, filename) < 0) {
+		fail("rename2");
+		goto out;
+	}
+
+	test_daemon();
+	test_waitsig();
+
+	if (getsockopt(sk1, 0, 0, NULL, 0) && errno != EOPNOTSUPP) {
+		fail("socket 1 didn't survive restore");
+		goto out;
+	}
+
+	if (getsockopt(sk2, 0, 0, NULL, 0) && errno != EOPNOTSUPP) {
+		fail("socket 2 didn't survive restore");
+		goto out;
+	}
+
+	if (stat(addr.sun_path, &sb) != 0) {
+		fail("%s doesn't exist after restore\n", addr.sun_path);
+		goto out;
+	}
+
+	pass();
+	ret = 0;
+out:
+	if (sk1 > 0)
+		close(sk1);
+	if (sk2 > 0)
+		close(sk2);
+	rmdir(dirname);
+	return ret;
+}

test/zdtm/static/deleted_standalone_unix.desc

+{'flavor': 'h ns uns'}