fsfreeze: new applet
NAME
fsfreeze - suspend access to a filesystem (Ext3/4, ReiserFS, JFS, XFS)
SYNOPSIS
fsfreeze --freeze|--unfreeze mountpoint
DESCRIPTION
fsfreeze suspends or resumes access to a filesystem.
fsfreeze halts any new access to the filesystem and creates a stable
image on disk.
AVAILABILITY
The fsfreeze command is part of the util-linux 2.28
function old new delta
fsfreeze_main - 81 +81
applet_names 2597 2606 +9
applet_main 1504 1508 +4
applet_suid 94 95 +1
applet_install_loc 188 189 +1
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/util-linux/fsfreeze.c b/util-linux/fsfreeze.c
new file mode 100644
index 0000000..fb1ebdc
--- /dev/null
+++ b/util-linux/fsfreeze.c
@@ -0,0 +1,54 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Copyright (C) 2017 Denys Vlasenko <vda.linux@googlemail.com>
+ *
+ * Licensed under GPLv2, see file LICENSE in this source tree.
+ */
+
+//config:config FSFREEZE
+//config: bool "fsfreeze"
+//config: default y
+//config: select PLATFORM_LINUX
+//config: select LONG_OPTS
+//config: help
+//config: Halt new accesses and flush writes on a mounted filesystem.
+
+//applet:IF_FSFREEZE(APPLET(fsfreeze, BB_DIR_SBIN, BB_SUID_DROP))
+
+//kbuild:lib-$(CONFIG_FSFREEZE) += fsfreeze.o
+
+//usage:#define fsfreeze_trivial_usage
+//usage: "--[un]freeze MOUNTPOINT"
+//usage:#define fsfreeze_full_usage "\n\n"
+//usage: "Flush and halt writes to MOUNTPOINT"
+
+#include "libbb.h"
+#include <linux/fs.h>
+
+#ifndef FIFREEZE
+# define FIFREEZE _IOWR('X', 119, int)
+# define FITHAW _IOWR('X', 120, int)
+#endif
+
+int fsfreeze_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int fsfreeze_main(int argc UNUSED_PARAM, char **argv)
+{
+ unsigned opts;
+ int fd;
+
+ applet_long_options =
+ "freeze\0" No_argument "\xff"
+ "unfreeze\0" No_argument "\xfe"
+ ;
+ /* exactly one non-option arg: the mountpoint */
+ /* one of opts is required */
+ /* opts are mutually exclusive */
+ opt_complementary = "=1:""\xff:\xfe:""\xff--\xfe:\xfe--\xff";
+ opts = getopt32(argv, "");
+
+ fd = xopen(argv[optind], O_RDONLY);
+ /* Works with NULL arg on linux-4.8.0 */
+ xioctl(fd, (opts & 1) ? FIFREEZE : FITHAW, NULL);
+
+ return EXIT_SUCCESS;
+}