btrfs-progs/cmds-subvolume.c

445 lines
8.8 KiB
C

/*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License v2 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., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <errno.h>
#include <sys/stat.h>
#include <libgen.h>
#include <limits.h>
#include "kerncompat.h"
#include "ioctl.h"
#include "btrfs_cmds.h"
/* btrfs-list.c */
int list_subvols(int fd, int print_parent, int get_default);
int find_updated_files(int fd, u64 root_id, u64 oldest_gen);
/*
* test if path is a directory
* this function return
* 0-> path exists but it is not a directory
* 1-> path exists and it is a directory
* -1 -> path is unaccessible
*/
static int test_isdir(char *path)
{
struct stat st;
int res;
res = stat(path, &st);
if(res < 0 )
return -1;
return S_ISDIR(st.st_mode);
}
int do_create_subvol(int argc, char **argv)
{
int res, fddst, len, e;
char *newname;
char *dstdir;
struct btrfs_ioctl_vol_args args;
char *dst = argv[1];
res = test_isdir(dst);
if(res >= 0 ){
fprintf(stderr, "ERROR: '%s' exists\n", dst);
return 12;
}
newname = strdup(dst);
newname = basename(newname);
dstdir = strdup(dst);
dstdir = dirname(dstdir);
if( !strcmp(newname,".") || !strcmp(newname,"..") ||
strchr(newname, '/') ){
fprintf(stderr, "ERROR: uncorrect subvolume name ('%s')\n",
newname);
return 14;
}
len = strlen(newname);
if (len == 0 || len >= BTRFS_VOL_NAME_MAX) {
fprintf(stderr, "ERROR: subvolume name too long ('%s)\n",
newname);
return 14;
}
fddst = open_file_or_dir(dstdir);
if (fddst < 0) {
fprintf(stderr, "ERROR: can't access to '%s'\n", dstdir);
return 12;
}
printf("Create subvolume '%s/%s'\n", dstdir, newname);
strncpy(args.name, newname, BTRFS_PATH_NAME_MAX);
res = ioctl(fddst, BTRFS_IOC_SUBVOL_CREATE, &args);
e = errno;
close(fddst);
if(res < 0 ){
fprintf( stderr, "ERROR: cannot create subvolume - %s\n",
strerror(e));
return 11;
}
return 0;
}
/*
* test if path is a subvolume:
* this function return
* 0-> path exists but it is not a subvolume
* 1-> path exists and it is a subvolume
* -1 -> path is unaccessible
*/
static int test_issubvolume(char *path)
{
struct stat st;
int res;
res = stat(path, &st);
if(res < 0 )
return -1;
return (st.st_ino == 256) && S_ISDIR(st.st_mode);
}
int do_delete_subvolume(int argc, char **argv)
{
int res, fd, len, e;
struct btrfs_ioctl_vol_args args;
char *dname, *vname, *cpath;
char *path = argv[1];
res = test_issubvolume(path);
if(res<0){
fprintf(stderr, "ERROR: error accessing '%s'\n", path);
return 12;
}
if(!res){
fprintf(stderr, "ERROR: '%s' is not a subvolume\n", path);
return 13;
}
cpath = realpath(path, 0);
dname = strdup(cpath);
dname = dirname(dname);
vname = strdup(cpath);
vname = basename(vname);
free(cpath);
if( !strcmp(vname,".") || !strcmp(vname,"..") ||
strchr(vname, '/') ){
fprintf(stderr, "ERROR: incorrect subvolume name ('%s')\n",
vname);
return 14;
}
len = strlen(vname);
if (len == 0 || len >= BTRFS_VOL_NAME_MAX) {
fprintf(stderr, "ERROR: snapshot name too long ('%s)\n",
vname);
return 14;
}
fd = open_file_or_dir(dname);
if (fd < 0) {
close(fd);
fprintf(stderr, "ERROR: can't access to '%s'\n", dname);
return 12;
}
printf("Delete subvolume '%s/%s'\n", dname, vname);
strncpy(args.name, vname, BTRFS_PATH_NAME_MAX);
res = ioctl(fd, BTRFS_IOC_SNAP_DESTROY, &args);
e = errno;
close(fd);
if(res < 0 ){
fprintf( stderr, "ERROR: cannot delete '%s/%s' - %s\n",
dname, vname, strerror(e));
return 11;
}
return 0;
}
int do_subvol_list(int argc, char **argv)
{
int fd;
int ret;
int print_parent = 0;
char *subvol;
int optind = 1;
while(1) {
int c = getopt(argc, argv, "p");
if (c < 0) break;
switch(c) {
case 'p':
print_parent = 1;
optind++;
break;
}
}
if (argc - optind != 1) {
fprintf(stderr, "ERROR: invalid arguments for subvolume list\n");
return 1;
}
subvol = argv[optind];
ret = test_issubvolume(subvol);
if (ret < 0) {
fprintf(stderr, "ERROR: error accessing '%s'\n", subvol);
return 12;
}
if (!ret) {
fprintf(stderr, "ERROR: '%s' is not a subvolume\n", subvol);
return 13;
}
fd = open_file_or_dir(subvol);
if (fd < 0) {
fprintf(stderr, "ERROR: can't access '%s'\n", subvol);
return 12;
}
ret = list_subvols(fd, print_parent, 0);
if (ret)
return 19;
return 0;
}
int do_clone(int argc, char **argv)
{
char *subvol, *dst;
int res, fd, fddst, len, e, optind = 0, readonly = 0;
char *newname;
char *dstdir;
struct btrfs_ioctl_vol_args_v2 args;
memset(&args, 0, sizeof(args));
while (1) {
int c = getopt(argc, argv, "r");
if (c < 0)
break;
switch (c) {
case 'r':
optind++;
readonly = 1;
break;
default:
fprintf(stderr,
"Invalid arguments for subvolume snapshot\n");
free(argv);
return 1;
}
}
if (argc - optind != 3) {
fprintf(stderr, "Invalid arguments for subvolume snapshot\n");
free(argv);
return 1;
}
subvol = argv[optind+1];
dst = argv[optind+2];
res = test_issubvolume(subvol);
if(res<0){
fprintf(stderr, "ERROR: error accessing '%s'\n", subvol);
return 12;
}
if(!res){
fprintf(stderr, "ERROR: '%s' is not a subvolume\n", subvol);
return 13;
}
res = test_isdir(dst);
if(res == 0 ){
fprintf(stderr, "ERROR: '%s' exists and it is not a directory\n", dst);
return 12;
}
if(res>0){
newname = strdup(subvol);
newname = basename(newname);
dstdir = dst;
}else{
newname = strdup(dst);
newname = basename(newname);
dstdir = strdup(dst);
dstdir = dirname(dstdir);
}
if( !strcmp(newname,".") || !strcmp(newname,"..") ||
strchr(newname, '/') ){
fprintf(stderr, "ERROR: incorrect snapshot name ('%s')\n",
newname);
return 14;
}
len = strlen(newname);
if (len == 0 || len >= BTRFS_VOL_NAME_MAX) {
fprintf(stderr, "ERROR: snapshot name too long ('%s)\n",
newname);
return 14;
}
fddst = open_file_or_dir(dstdir);
if (fddst < 0) {
fprintf(stderr, "ERROR: can't access to '%s'\n", dstdir);
return 12;
}
fd = open_file_or_dir(subvol);
if (fd < 0) {
close(fddst);
fprintf(stderr, "ERROR: can't access to '%s'\n", dstdir);
return 12;
}
if (readonly) {
args.flags |= BTRFS_SUBVOL_RDONLY;
printf("Create a readonly snapshot of '%s' in '%s/%s'\n",
subvol, dstdir, newname);
} else {
printf("Create a snapshot of '%s' in '%s/%s'\n",
subvol, dstdir, newname);
}
args.fd = fd;
strncpy(args.name, newname, BTRFS_SUBVOL_NAME_MAX);
res = ioctl(fddst, BTRFS_IOC_SNAP_CREATE_V2, &args);
e = errno;
close(fd);
close(fddst);
if(res < 0 ){
fprintf( stderr, "ERROR: cannot snapshot '%s' - %s\n",
subvol, strerror(e));
return 11;
}
return 0;
}
int do_get_default_subvol(int nargs, char **argv)
{
int fd;
int ret;
char *subvol;
subvol = argv[1];
ret = test_issubvolume(subvol);
if (ret < 0) {
fprintf(stderr, "ERROR: error accessing '%s'\n", subvol);
return 12;
}
if (!ret) {
fprintf(stderr, "ERROR: '%s' is not a subvolume\n", subvol);
return 13;
}
fd = open_file_or_dir(subvol);
if (fd < 0) {
fprintf(stderr, "ERROR: can't access '%s'\n", subvol);
return 12;
}
ret = list_subvols(fd, 0, 1);
if (ret)
return 19;
return 0;
}
int do_set_default_subvol(int nargs, char **argv)
{
int ret=0, fd, e;
u64 objectid;
char *path = argv[2];
char *subvolid = argv[1];
fd = open_file_or_dir(path);
if (fd < 0) {
fprintf(stderr, "ERROR: can't access to '%s'\n", path);
return 12;
}
objectid = (unsigned long long)strtoll(subvolid, NULL, 0);
if (errno == ERANGE) {
fprintf(stderr, "ERROR: invalid tree id (%s)\n",subvolid);
return 30;
}
ret = ioctl(fd, BTRFS_IOC_DEFAULT_SUBVOL, &objectid);
e = errno;
close(fd);
if( ret < 0 ){
fprintf(stderr, "ERROR: unable to set a new default subvolume - %s\n",
strerror(e));
return 30;
}
return 0;
}
int do_find_newer(int argc, char **argv)
{
int fd;
int ret;
char *subvol;
u64 last_gen;
subvol = argv[1];
last_gen = atoll(argv[2]);
ret = test_issubvolume(subvol);
if (ret < 0) {
fprintf(stderr, "ERROR: error accessing '%s'\n", subvol);
return 12;
}
if (!ret) {
fprintf(stderr, "ERROR: '%s' is not a subvolume\n", subvol);
return 13;
}
fd = open_file_or_dir(subvol);
if (fd < 0) {
fprintf(stderr, "ERROR: can't access '%s'\n", subvol);
return 12;
}
ret = find_updated_files(fd, 0, last_gen);
if (ret)
return 19;
return 0;
}