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/*
* Squashfs - a compressed read only filesystem for Linux
*
* Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008
* Phillip Lougher <phillip@squashfs.org.uk>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2,
* or (at your option) any later version.
*
* 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, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* symlink.c
*/
/*
* This file implements code to handle symbolic links.
*
* The data contents of symbolic links are stored inside the symbolic
* link inode within the inode table. This allows the normally small symbolic
* link to be compressed as part of the inode table, achieving much greater
* compression than if the symbolic link was compressed individually.
*/
#include <malloc.h>
#include <linux/fs.h>
#include <linux/stat.h>
#include <linux/pagemap.h>
#include "squashfs_fs.h"
#include "squashfs_fs_sb.h"
#include "squashfs_fs_i.h"
#include "squashfs.h"
static const char *squashfs_get_link(struct dentry *dentry, struct inode *inode)
{
struct super_block *sb = inode->i_sb;
int index = 0;
u64 block = squashfs_i(inode)->start;
int offset = squashfs_i(inode)->offset;
int length = min_t(int, i_size_read(inode) - index, PAGE_SIZE);
int bytes;
unsigned char *symlink;
TRACE("Entered squashfs_symlink_readpage, start block "
"%llx, offset %x\n", block, offset);
symlink = malloc(length + 1);
if (!symlink)
return NULL;
symlink[length] = 0;
bytes = squashfs_read_metadata(sb, symlink, &block, &offset, length);
if (bytes < 0) {
ERROR("Unable to read symlink [%llx:%x]\n",
squashfs_i(inode)->start,
squashfs_i(inode)->offset);
goto error_out;
}
inode->i_link = symlink;
return inode->i_link;
error_out:
free(symlink);
return NULL;
}
const struct inode_operations squashfs_symlink_inode_ops = {
.get_link = squashfs_get_link,
};
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