legacy/libisofs_outdated/branches/thomas/libisofs/tree.c

960 lines
26 KiB
C

/*
* Copyright (c) 2007 Vreixo Formoso
*
* This file is part of the libisofs project; 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. See COPYING file for details.
*/
/*
* Functions that act on the iso tree.
*/
#include "libisofs.h"
#include "node.h"
#include "image.h"
#include "fsource.h"
#include "builder.h"
#include "messages.h"
#include "tree.h"
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <limits.h>
#include <stdio.h>
#include <fnmatch.h>
/**
* Add a new directory to the iso tree.
*
* @param parent
* the dir where the new directory will be created
* @param name
* name for the new dir. If a node with same name already exists on
* parent, this functions fails with ISO_NODE_NAME_NOT_UNIQUE.
* @param dir
* place where to store a pointer to the newly created dir. No extra
* ref is addded, so you will need to call iso_node_ref() if you really
* need it. You can pass NULL in this parameter if you don't need the
* pointer.
* @return
* number of nodes in dir if succes, < 0 otherwise
* Possible errors:
* ISO_NULL_POINTER, if parent or name are NULL
* ISO_NODE_NAME_NOT_UNIQUE, a node with same name already exists
*/
int iso_tree_add_new_dir(IsoDir *parent, const char *name, IsoDir **dir)
{
int ret;
char *n;
IsoDir *node;
IsoNode **pos;
time_t now;
if (parent == NULL || name == NULL) {
return ISO_NULL_POINTER;
}
if (dir) {
*dir = NULL;
}
/* find place where to insert and check if it exists */
if (iso_dir_exists(parent, name, &pos)) {
/* a node with same name already exists */
return ISO_NODE_NAME_NOT_UNIQUE;
}
n = strdup(name);
ret = iso_node_new_dir(n, &node);
if (ret < 0) {
free(n);
return ret;
}
/* permissions from parent */
iso_node_set_permissions((IsoNode*)node, parent->node.mode);
iso_node_set_uid((IsoNode*)node, parent->node.uid);
iso_node_set_gid((IsoNode*)node, parent->node.gid);
iso_node_set_hidden((IsoNode*)node, parent->node.hidden);
/* current time */
now = time(NULL);
iso_node_set_atime((IsoNode*)node, now);
iso_node_set_ctime((IsoNode*)node, now);
iso_node_set_mtime((IsoNode*)node, now);
if (dir) {
*dir = node;
}
/* add to dir */
return iso_dir_insert(parent, (IsoNode*)node, pos, ISO_REPLACE_NEVER);
}
/**
* Add a new symlink to the directory tree. Permissions are set to 0777,
* owner and hidden atts are taken from parent. You can modify any of them
* later.
*
* @param parent
* the dir where the new symlink will be created
* @param name
* name for the new dir. If a node with same name already exists on
* parent, this functions fails with ISO_NODE_NAME_NOT_UNIQUE.
* @param dest
* destination of the link
* @param link
* place where to store a pointer to the newly created link. No extra
* ref is addded, so you will need to call iso_node_ref() if you really
* need it. You can pass NULL in this parameter if you don't need the
* pointer
* @return
* number of nodes in parent if success, < 0 otherwise
* Possible errors:
* ISO_NULL_POINTER, if parent, name or dest are NULL
* ISO_NODE_NAME_NOT_UNIQUE, a node with same name already exists
* ISO_OUT_OF_MEM
*/
int iso_tree_add_new_symlink(IsoDir *parent, const char *name,
const char *dest, IsoSymlink **link)
{
int ret;
char *n, *d;
IsoSymlink *node;
IsoNode **pos;
time_t now;
if (parent == NULL || name == NULL || dest == NULL) {
return ISO_NULL_POINTER;
}
if (link) {
*link = NULL;
}
/* find place where to insert */
if (iso_dir_exists(parent, name, &pos)) {
/* a node with same name already exists */
return ISO_NODE_NAME_NOT_UNIQUE;
}
n = strdup(name);
d = strdup(dest);
ret = iso_node_new_symlink(n, d, &node);
if (ret < 0) {
free(n);
free(d);
return ret;
}
/* permissions from parent */
iso_node_set_permissions((IsoNode*)node, 0777);
iso_node_set_uid((IsoNode*)node, parent->node.uid);
iso_node_set_gid((IsoNode*)node, parent->node.gid);
iso_node_set_hidden((IsoNode*)node, parent->node.hidden);
/* current time */
now = time(NULL);
iso_node_set_atime((IsoNode*)node, now);
iso_node_set_ctime((IsoNode*)node, now);
iso_node_set_mtime((IsoNode*)node, now);
if (link) {
*link = node;
}
/* add to dir */
return iso_dir_insert(parent, (IsoNode*)node, pos, ISO_REPLACE_NEVER);
}
/**
* Add a new special file to the directory tree. As far as libisofs concerns,
* an special file is a block device, a character device, a FIFO (named pipe)
* or a socket. You can choose the specific kind of file you want to add
* by setting mode propertly (see man 2 stat).
*
* Note that special files are only written to image when Rock Ridge
* extensions are enabled. Moreover, a special file is just a directory entry
* in the image tree, no data is written beyond that.
*
* Owner and hidden atts are taken from parent. You can modify any of them
* later.
*
* @param parent
* the dir where the new special file will be created
* @param name
* name for the new special file. If a node with same name already exists
* on parent, this functions fails with ISO_NODE_NAME_NOT_UNIQUE.
* @param mode
* file type and permissions for the new node. Note that you can't
* specify any kind of file here, only special types are allowed. i.e,
* S_IFSOCK, S_IFBLK, S_IFCHR and S_IFIFO are valid types; S_IFLNK,
* S_IFREG and S_IFDIR aren't.
* @param dev
* device ID, equivalent to the st_rdev field in man 2 stat.
* @param special
* place where to store a pointer to the newly created special file. No
* extra ref is addded, so you will need to call iso_node_ref() if you
* really need it. You can pass NULL in this parameter if you don't need
* the pointer.
* @return
* number of nodes in parent if success, < 0 otherwise
* Possible errors:
* ISO_NULL_POINTER, if parent, name or dest are NULL
* ISO_NODE_NAME_NOT_UNIQUE, a node with same name already exists
* ISO_OUT_OF_MEM
*
*/
int iso_tree_add_new_special(IsoDir *parent, const char *name, mode_t mode,
dev_t dev, IsoSpecial **special)
{
int ret;
char *n;
IsoSpecial *node;
IsoNode **pos;
time_t now;
if (parent == NULL || name == NULL) {
return ISO_NULL_POINTER;
}
if (S_ISLNK(mode) || S_ISREG(mode) || S_ISDIR(mode)) {
return ISO_WRONG_ARG_VALUE;
}
if (special) {
*special = NULL;
}
/* find place where to insert */
if (iso_dir_exists(parent, name, &pos)) {
/* a node with same name already exists */
return ISO_NODE_NAME_NOT_UNIQUE;
}
n = strdup(name);
ret = iso_node_new_special(n, mode, dev, &node);
if (ret < 0) {
free(n);
return ret;
}
/* atts from parent */
iso_node_set_uid((IsoNode*)node, parent->node.uid);
iso_node_set_gid((IsoNode*)node, parent->node.gid);
iso_node_set_hidden((IsoNode*)node, parent->node.hidden);
/* current time */
now = time(NULL);
iso_node_set_atime((IsoNode*)node, now);
iso_node_set_ctime((IsoNode*)node, now);
iso_node_set_mtime((IsoNode*)node, now);
if (special) {
*special = node;
}
/* add to dir */
return iso_dir_insert(parent, (IsoNode*)node, pos, ISO_REPLACE_NEVER);
}
/**
* Add a new regular file to the iso tree. Permissions are set to 0444,
* owner and hidden atts are taken from parent. You can modify any of them
* later.
*
* @param parent
* the dir where the new file will be created
* @param name
* name for the new file. If a node with same name already exists on
* parent, this functions fails with ISO_NODE_NAME_NOT_UNIQUE.
* @param stream
* IsoStream for the contents of the file
* @param file
* place where to store a pointer to the newly created file. No extra
* ref is addded, so you will need to call iso_node_ref() if you really
* need it. You can pass NULL in this parameter if you don't need the
* pointer
* @return
* number of nodes in parent if success, < 0 otherwise
* Possible errors:
* ISO_NULL_POINTER, if parent, name or dest are NULL
* ISO_NODE_NAME_NOT_UNIQUE, a node with same name already exists
* ISO_OUT_OF_MEM
*
* @since 0.6.4
*/
int iso_tree_add_new_file(IsoDir *parent, const char *name, IsoStream *stream,
IsoFile **file)
{
int ret;
char *n;
IsoFile *node;
IsoNode **pos;
time_t now;
if (parent == NULL || name == NULL || stream == NULL) {
return ISO_NULL_POINTER;
}
if (file) {
*file = NULL;
}
/* find place where to insert */
if (iso_dir_exists(parent, name, &pos)) {
/* a node with same name already exists */
return ISO_NODE_NAME_NOT_UNIQUE;
}
n = strdup(name);
ret = iso_node_new_file(n, stream, &node);
if (ret < 0) {
free(n);
return ret;
}
/* permissions from parent */
iso_node_set_permissions((IsoNode*)node, 0444);
iso_node_set_uid((IsoNode*)node, parent->node.uid);
iso_node_set_gid((IsoNode*)node, parent->node.gid);
iso_node_set_hidden((IsoNode*)node, parent->node.hidden);
/* current time */
now = time(NULL);
iso_node_set_atime((IsoNode*)node, now);
iso_node_set_ctime((IsoNode*)node, now);
iso_node_set_mtime((IsoNode*)node, now);
if (file) {
*file = node;
}
/* add to dir */
return iso_dir_insert(parent, (IsoNode*)node, pos, ISO_REPLACE_NEVER);
}
/**
* Set whether to follow or not symbolic links when added a file from a source
* to IsoImage.
*/
void iso_tree_set_follow_symlinks(IsoImage *image, int follow)
{
image->follow_symlinks = follow ? 1 : 0;
}
/**
* Get current setting for follow_symlinks.
*
* @see iso_tree_set_follow_symlinks
*/
int iso_tree_get_follow_symlinks(IsoImage *image)
{
return image->follow_symlinks;
}
/**
* Set whether to skip or not hidden files when adding a directory recursibely.
* Default behavior is to not ignore them, i.e., to add hidden files to image.
*/
void iso_tree_set_ignore_hidden(IsoImage *image, int skip)
{
image->ignore_hidden = skip ? 1 : 0;
}
/**
* Get current setting for ignore_hidden.
*
* @see iso_tree_set_ignore_hidden
*/
int iso_tree_get_ignore_hidden(IsoImage *image)
{
return image->ignore_hidden;
}
void iso_tree_set_replace_mode(IsoImage *image, enum iso_replace_mode mode)
{
image->replace = mode;
}
enum iso_replace_mode iso_tree_get_replace_mode(IsoImage *image)
{
return image->replace;
}
/**
* Set whether to skip or not special files. Default behavior is to not skip
* them. Note that, despite of this setting, special files won't never be added
* to an image unless RR extensions were enabled.
*
* @param skip
* Bitmask to determine what kind of special files will be skipped:
* bit0: ignore FIFOs
* bit1: ignore Sockets
* bit2: ignore char devices
* bit3: ignore block devices
*/
void iso_tree_set_ignore_special(IsoImage *image, int skip)
{
image->ignore_special = skip & 0x0F;
}
/**
* Get current setting for ignore_special.
*
* @see iso_tree_set_ignore_special
*/
int iso_tree_get_ignore_special(IsoImage *image)
{
return image->ignore_special;
}
/**
* Set a callback function that libisofs will call for each file that is
* added to the given image by a recursive addition function. This includes
* image import.
*
* @param report
* pointer to a function that will be called just before a file will be
* added to the image. You can control whether the file will be in fact
* added or ignored.
* This function should return 1 to add the file, 0 to ignore it and
* continue, < 0 to abort the process
* NULL is allowed if you don't want any callback.
*/
void iso_tree_set_report_callback(IsoImage *image,
int (*report)(IsoImage*, IsoFileSource*))
{
image->report = report;
}
/**
* Add a excluded path. These are paths that won't never added to image,
* and will be excluded even when adding recursively its parent directory.
*
* For example, in
*
* iso_tree_add_exclude(image, "/home/user/data/private");
* iso_tree_add_dir_rec(image, root, "/home/user/data");
*
* the directory /home/user/data/private won't be added to image.
*
* @return
* 1 on success, < 0 on error
*/
int iso_tree_add_exclude(IsoImage *image, const char *path)
{
if (image == NULL || path == NULL) {
return ISO_NULL_POINTER;
}
image->excludes = realloc(image->excludes, ++image->nexcludes *
sizeof(void*));
if (image->excludes == NULL) {
return ISO_OUT_OF_MEM;
}
image->excludes[image->nexcludes - 1] = strdup(path);
if (image->excludes[image->nexcludes - 1] == NULL) {
return ISO_OUT_OF_MEM;
}
return ISO_SUCCESS;
}
/**
* Remove a previously added exclude.
*
* @see iso_tree_add_exclude
* @return
* 1 on success, 0 exclude do not exists, < 0 on error
*/
int iso_tree_remove_exclude(IsoImage *image, const char *path)
{
size_t i, j;
if (image == NULL || path == NULL) {
return ISO_NULL_POINTER;
}
for (i = 0; i < image->nexcludes; ++i) {
if (strcmp(image->excludes[i], path) == 0) {
/* exclude found */
free(image->excludes[i]);
--image->nexcludes;
for (j = i; j < image->nexcludes; ++j) {
image->excludes[j] = image->excludes[j+1];
}
image->excludes = realloc(image->excludes, image->nexcludes *
sizeof(void*));
return ISO_SUCCESS;
}
}
return 0;
}
static
int iso_tree_add_node_builder(IsoImage *image, IsoDir *parent,
IsoFileSource *src, IsoNodeBuilder *builder,
IsoNode **node)
{
int result;
IsoNode *new;
IsoNode **pos;
char *name;
if (parent == NULL || src == NULL || builder == NULL) {
return ISO_NULL_POINTER;
}
if (node) {
*node = NULL;
}
name = iso_file_source_get_name(src);
/* find place where to insert */
result = iso_dir_exists(parent, name, &pos);
free(name);
if (result) {
/* a node with same name already exists */
return ISO_NODE_NAME_NOT_UNIQUE;
}
result = builder->create_node(builder, image, src, &new);
if (result < 0) {
return result;
}
if (node) {
*node = new;
}
/* finally, add node to parent */
return iso_dir_insert(parent, (IsoNode*)new, pos, ISO_REPLACE_NEVER);
}
int iso_tree_add_node(IsoImage *image, IsoDir *parent, const char *path,
IsoNode **node)
{
int result;
IsoFilesystem *fs;
IsoFileSource *file;
if (image == NULL || parent == NULL || path == NULL) {
return ISO_NULL_POINTER;
}
fs = image->fs;
result = fs->get_by_path(fs, path, &file);
if (result < 0) {
return result;
}
result = iso_tree_add_node_builder(image, parent, file, image->builder,
node);
/* free the file */
iso_file_source_unref(file);
return result;
}
int iso_tree_add_new_node(IsoImage *image, IsoDir *parent, const char *name,
const char *path, IsoNode **node)
{
int result;
IsoFilesystem *fs;
IsoFileSource *file;
IsoNode *new;
IsoNode **pos;
if (image == NULL || parent == NULL || name == NULL || path == NULL) {
return ISO_NULL_POINTER;
}
if (node) {
*node = NULL;
}
fs = image->fs;
result = fs->get_by_path(fs, path, &file);
if (result < 0) {
return result;
}
/* find place where to insert */
result = iso_dir_exists(parent, name, &pos);
if (result) {
/* a node with same name already exists */
iso_file_source_unref(file);
return ISO_NODE_NAME_NOT_UNIQUE;
}
result = image->builder->create_node(image->builder, image, file, &new);
/* free the file */
iso_file_source_unref(file);
if (result < 0) {
return result;
}
result = iso_node_set_name(new, name);
if (result < 0) {
iso_node_unref(new);
return result;
}
if (node) {
*node = new;
}
/* finally, add node to parent */
return iso_dir_insert(parent, new, pos, ISO_REPLACE_NEVER);
}
int iso_tree_add_new_cut_out_node(IsoImage *image, IsoDir *parent,
const char *name, const char *path,
off_t offset, off_t size,
IsoNode **node)
{
int result;
struct stat info;
IsoFilesystem *fs;
IsoFileSource *src;
IsoFile *new;
IsoNode **pos;
IsoStream *stream;
if (image == NULL || parent == NULL || name == NULL || path == NULL) {
return ISO_NULL_POINTER;
}
if (node) {
*node = NULL;
}
/* find place where to insert */
result = iso_dir_exists(parent, name, &pos);
if (result) {
/* a node with same name already exists */
return ISO_NODE_NAME_NOT_UNIQUE;
}
fs = image->fs;
result = fs->get_by_path(fs, path, &src);
if (result < 0) {
return result;
}
result = iso_file_source_stat(src, &info);
if (result < 0) {
iso_file_source_unref(src);
return result;
}
if (!S_ISREG(info.st_mode)) {
return ISO_WRONG_ARG_VALUE;
}
if (offset >= info.st_size) {
return ISO_WRONG_ARG_VALUE;
}
/* force regular file */
result = image->builder->create_file(image->builder, image, src, &new);
/* free the file */
iso_file_source_unref(src);
if (result < 0) {
return result;
}
/* replace file iso stream with a cut-out-stream */
result = iso_cut_out_stream_new(src, offset, size, &stream);
if (result < 0) {
iso_node_unref((IsoNode*)new);
return result;
}
iso_stream_unref(new->stream);
new->stream = stream;
result = iso_node_set_name((IsoNode*)new, name);
if (result < 0) {
iso_node_unref((IsoNode*)new);
return result;
}
if (node) {
*node = (IsoNode*)new;
}
/* finally, add node to parent */
return iso_dir_insert(parent, (IsoNode*)new, pos, ISO_REPLACE_NEVER);
}
static
int check_excludes(IsoImage *image, const char *path)
{
int i;
for (i = 0; i < image->nexcludes; ++i) {
char *exclude = image->excludes[i];
if (exclude[0] == '/') {
/* absolute exclude, must completely match path */
if (!fnmatch(exclude, path, FNM_PERIOD|FNM_PATHNAME)) {
return 1;
}
} else {
/* relative exclude, it is enought if a part of the path matches */
char *pos = (char*)path;
while (pos != NULL) {
pos++;
if (!fnmatch(exclude, pos, FNM_PERIOD|FNM_PATHNAME)) {
return 1;
}
pos = strchr(pos, '/');
}
}
}
return 0;
}
static
int check_hidden(IsoImage *image, const char *name)
{
return (image->ignore_hidden && name[0] == '.');
}
static
int check_special(IsoImage *image, mode_t mode)
{
if (image->ignore_special != 0) {
switch(mode & S_IFMT) {
case S_IFBLK:
return image->ignore_special & 0x08 ? 1 : 0;
case S_IFCHR:
return image->ignore_special & 0x04 ? 1 : 0;
case S_IFSOCK:
return image->ignore_special & 0x02 ? 1 : 0;
case S_IFIFO:
return image->ignore_special & 0x01 ? 1 : 0;
default:
return 0;
}
}
return 0;
}
/**
* Recursively add a given directory to the image tree.
*
* @return
* 1 continue, < 0 error (ISO_CANCELED stop)
*/
int iso_add_dir_src_rec(IsoImage *image, IsoDir *parent, IsoFileSource *dir)
{
int ret;
IsoNodeBuilder *builder;
IsoFileSource *file;
IsoNode **pos;
struct stat info;
char *name, *path;
IsoNode *new;
enum iso_replace_mode replace;
ret = iso_file_source_open(dir);
if (ret < 0) {
char *path = iso_file_source_get_path(dir);
/* instead of the probable error, we throw a sorry event */
ret = iso_msg_submit(image->id, ISO_FILE_CANT_ADD, ret,
"Can't open dir %s", path);
free(path);
return ret;
}
builder = image->builder;
/* iterate over all directory children */
while (1) {
int skip = 0;
ret = iso_file_source_readdir(dir, &file);
if (ret <= 0) {
if (ret < 0) {
/* error reading dir */
ret = iso_msg_submit(image->id, ret, ret, "Error reading dir");
}
break;
}
path = iso_file_source_get_path(file);
name = strrchr(path, '/') + 1;
if (image->follow_symlinks) {
ret = iso_file_source_stat(file, &info);
} else {
ret = iso_file_source_lstat(file, &info);
}
if (ret < 0) {
goto dir_rec_continue;
}
if (check_excludes(image, path)) {
iso_msg_debug(image->id, "Skipping excluded file %s", path);
skip = 1;
} else if (check_hidden(image, name)) {
iso_msg_debug(image->id, "Skipping hidden file %s", path);
skip = 1;
} else if (check_special(image, info.st_mode)) {
iso_msg_debug(image->id, "Skipping special file %s", path);
skip = 1;
}
if (skip) {
goto dir_rec_continue;
}
replace = image->replace;
/* find place where to insert */
ret = iso_dir_exists(parent, name, &pos);
/* TODO
* if (ret && replace == ISO_REPLACE_ASK) {
* replace = /....
* }
*/
/* chek if we must insert or not */
/* TODO check for other replace behavior */
if (ret && (replace == ISO_REPLACE_NEVER)) {
/* skip file */
goto dir_rec_continue;
}
/* if we are here we must insert. Give user a chance for cancel */
if (image->report) {
int r = image->report(image, file);
if (r <= 0) {
ret = (r < 0 ? ISO_CANCELED : ISO_SUCCESS);
goto dir_rec_continue;
}
}
ret = builder->create_node(builder, image, file, &new);
if (ret < 0) {
ret = iso_msg_submit(image->id, ISO_FILE_CANT_ADD, ret,
"Error when adding file %s", path);
goto dir_rec_continue;
}
/* ok, node has correctly created, we need to add it */
ret = iso_dir_insert(parent, new, pos, replace);
if (ret < 0) {
iso_node_unref(new);
if (ret != ISO_NODE_NAME_NOT_UNIQUE) {
/* error */
goto dir_rec_continue;
} else {
/* file ignored because a file with same node already exists */
iso_msg_debug(image->id, "Skipping file %s. A node with same "
"file already exists", path);
ret = 0;
}
} else {
iso_msg_debug(image->id, "Added file %s", path);
}
/* finally, if the node is a directory we need to recurse */
if (new->type == LIBISO_DIR && S_ISDIR(info.st_mode)) {
ret = iso_add_dir_src_rec(image, (IsoDir*)new, file);
}
dir_rec_continue:;
free(path);
iso_file_source_unref(file);
/* check for error severity to decide what to do */
if (ret < 0) {
ret = iso_msg_submit(image->id, ret, 0, NULL);
if (ret < 0) {
break;
}
}
} /* while */
iso_file_source_close(dir);
return ret < 0 ? ret : ISO_SUCCESS;
}
int iso_tree_add_dir_rec(IsoImage *image, IsoDir *parent, const char *dir)
{
int result;
struct stat info;
IsoFilesystem *fs;
IsoFileSource *file;
if (image == NULL || parent == NULL || dir == NULL) {
return ISO_NULL_POINTER;
}
fs = image->fs;
result = fs->get_by_path(fs, dir, &file);
if (result < 0) {
return result;
}
/* we also allow dir path to be a symlink to a dir */
result = iso_file_source_stat(file, &info);
if (result < 0) {
iso_file_source_unref(file);
return result;
}
if (!S_ISDIR(info.st_mode)) {
iso_file_source_unref(file);
return ISO_FILE_IS_NOT_DIR;
}
result = iso_add_dir_src_rec(image, parent, file);
iso_file_source_unref(file);
return result;
}
int iso_tree_path_to_node(IsoImage *image, const char *path, IsoNode **node)
{
int result;
IsoNode *n;
IsoDir *dir;
char *ptr, *brk_info, *component;
if (image == NULL || path == NULL) {
return ISO_NULL_POINTER;
}
/* get the first child at the root of the image that is "/" */
dir = image->root;
n = (IsoNode *)dir;
if (!strcmp(path, "/")) {
if (node) {
*node = n;
}
return ISO_SUCCESS;
}
ptr = strdup(path);
result = 0;
/* get the first component of the path */
component = strtok_r(ptr, "/", &brk_info);
while (component) {
if (n->type != LIBISO_DIR) {
n = NULL;
break;
}
dir = (IsoDir *)n;
result = iso_dir_get_node(dir, component, &n);
if (result != 1) {
n = NULL;
break;
}
component = strtok_r(NULL, "/", &brk_info);
}
free(ptr);
if (node) {
*node = n;
}
return result;
}