lxc_snapshot.c revision f10fad2f53e3f4f2f862bacf218a5aa7feceb505
/*
*
* Copyright © 2013 Serge Hallyn <serge.hallyn@ubuntu.com>.
* Copyright © 2013 Canonical Ltd.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2, as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "config.h"
#include <stdio.h>
#include <libgen.h>
#include <unistd.h>
#include <ctype.h>
#include <sys/types.h>
#include <fcntl.h>
#include <lxc/lxccontainer.h>
#include "lxc.h"
#include "log.h"
#include "bdev.h"
#include "arguments.h"
#include "utils.h"
lxc_log_define(lxc_snapshot_ui, lxc);
static char *newname;
static char *snapshot;
#define DO_SNAP 0
#define DO_LIST 1
#define DO_RESTORE 2
#define DO_DESTROY 3
static int action;
static int print_comments;
static char *commentfile;
static int do_snapshot(struct lxc_container *c)
{
int ret;
ret = c->snapshot(c, commentfile);
if (ret < 0) {
ERROR("Error creating a snapshot");
return -1;
}
INFO("Created snapshot snap%d", ret);
return 0;
}
static void print_file(char *path)
{
if (!path)
return;
FILE *f = fopen(path, "r");
char *line = NULL;
size_t sz = 0;
if (!f)
return;
while (getline(&line, &sz, f) != -1) {
printf("%s", line);
}
free(line);
fclose(f);
}
static int do_list_snapshots(struct lxc_container *c)
{
struct lxc_snapshot *s;
int i, n;
n = c->snapshot_list(c, &s);
if (n < 0) {
ERROR("Error listing snapshots");
return -1;
}
if (n == 0) {
printf("No snapshots\n");
return 0;
}
for (i=0; i<n; i++) {
printf("%s (%s) %s\n", s[i].name, s[i].lxcpath, s[i].timestamp);
if (print_comments)
print_file(s[i].comment_pathname);
s[i].free(&s[i]);
}
free(s);
return 0;
}
static int do_restore_snapshots(struct lxc_container *c)
{
if (c->snapshot_restore(c, snapshot, newname))
return 0;
ERROR("Error restoring snapshot %s", snapshot);
return -1;
}
static int do_destroy_snapshots(struct lxc_container *c)
{
bool bret;
if (strcmp(snapshot, "ALL") == 0)
bret = c->snapshot_destroy_all(c);
else
bret = c->snapshot_destroy(c, snapshot);
if (bret)
return 0;
ERROR("Error destroying snapshot %s", snapshot);
return -1;
}
static int my_parser(struct lxc_arguments* args, int c, char* arg)
{
switch (c) {
case 'L': action = DO_LIST; break;
case 'r': snapshot = arg; action = DO_RESTORE; break;
case 'd': snapshot = arg; action = DO_DESTROY; break;
case 'c': commentfile = arg; break;
case 'C': print_comments = true; break;
}
return 0;
}
static const struct option my_longopts[] = {
{"list", no_argument, 0, 'L'},
{"restore", required_argument, 0, 'r'},
{"destroy", required_argument, 0, 'd'},
{"comment", required_argument, 0, 'c'},
{"showcomments", no_argument, 0, 'C'},
LXC_COMMON_OPTIONS
};
static struct lxc_arguments my_args = {
.progname = "lxc-snapshot",
.help = "\
--name=NAME [-P lxcpath] [-L [-C]] [-c commentfile] [-r snapname [newname]]\n\
\n\
lxc-snapshot snapshots a container\n\
\n\
Options :\n\
-n, --name=NAME NAME for name of the container\n\
-L, --list list snapshots\n\
-C, --showcomments show snapshot comments in list\n\
-c, --comment=file add file as a comment\n\
-r, --restore=name restore snapshot name, i.e. 'snap0'\n\
-d, --destroy=name destroy snapshot name, i.e. 'snap0'\n\
use ALL to destroy all snapshots\n",
.options = my_longopts,
.parser = my_parser,
.checker = NULL,
};
/*
* lxc-snapshot -P lxcpath -n container
* lxc-snapshot -P lxcpath -n container -l
* lxc-snapshot -P lxcpath -n container -r snap3 recovered_1
*/
int main(int argc, char *argv[])
{
struct lxc_container *c;
int ret = 0;
if (lxc_arguments_parse(&my_args, argc, argv))
exit(1);
if (!my_args.log_file)
my_args.log_file = "none";
if (my_args.argc > 1) {
ERROR("Too many arguments");
exit(1);
}
if (my_args.argc == 1)
newname = my_args.argv[0];
if (lxc_log_init(my_args.name, my_args.log_file, my_args.log_priority,
my_args.progname, my_args.quiet, my_args.lxcpath[0]))
exit(1);
lxc_log_options_no_override();
if (geteuid()) {
if (access(my_args.lxcpath[0], O_RDWR) < 0) {
fprintf(stderr, "You lack access to %s\n", my_args.lxcpath[0]);
exit(1);
}
}
c = lxc_container_new(my_args.name, my_args.lxcpath[0]);
if (!c) {
fprintf(stderr, "System error loading container\n");
exit(1);
}
if (!c->may_control(c)) {
fprintf(stderr, "Insufficent privileges to control %s\n", my_args.name);
lxc_container_put(c);
exit(1);
}
switch(action) {
case DO_SNAP:
ret = do_snapshot(c);
break;
case DO_LIST:
ret = do_list_snapshots(c);
break;
case DO_RESTORE:
ret = do_restore_snapshots(c);
break;
case DO_DESTROY:
ret = do_destroy_snapshots(c);
break;
}
lxc_container_put(c);
if (ret == 0)
exit(EXIT_SUCCESS);
exit(EXIT_FAILURE);
}