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/*
* linux/fs/isofs/symlink.c
*
* (C) 1992 Eric Youngdale Modified for ISO9660 filesystem.
*
* Copyright (C) 1991, 1992 Linus Torvalds
*
* isofs symlink handling code. This is only used with the Rock Ridge
* extensions to iso9660
*/
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/fs.h>
#include <linux/iso_fs.h>
#include <linux/stat.h>
#include <linux/malloc.h>
#include <asm/uaccess.h>
static int isofs_readlink(struct dentry *, char *, int);
static struct dentry * isofs_follow_link(struct dentry *, struct dentry *);
/*
* symlinks can't do much...
*/
struct inode_operations isofs_symlink_inode_operations = {
NULL, /* no file-operations */
NULL, /* create */
NULL, /* lookup */
NULL, /* link */
NULL, /* unlink */
NULL, /* symlink */
NULL, /* mkdir */
NULL, /* rmdir */
NULL, /* mknod */
NULL, /* rename */
isofs_readlink, /* readlink */
isofs_follow_link, /* follow_link */
NULL, /* readpage */
NULL, /* writepage */
NULL, /* bmap */
NULL, /* truncate */
NULL /* permission */
};
static int isofs_readlink(struct dentry * dentry, char * buffer, int buflen)
{
char * pnt;
int i;
if (buflen > 1023)
buflen = 1023;
pnt = get_rock_ridge_symlink(dentry->d_inode);
if (!pnt)
return 0;
i = strlen(pnt);
if (i > buflen)
i = buflen;
if (copy_to_user(buffer, pnt, i))
i = -EFAULT;
kfree(pnt);
return i;
}
static struct dentry * isofs_follow_link(struct dentry * dentry,
struct dentry *base)
{
char * pnt;
pnt = get_rock_ridge_symlink(dentry->d_inode);
if(!pnt) {
dput(base);
return ERR_PTR(-ELOOP);
}
base = lookup_dentry(pnt, base, 1);
kfree(pnt);
return base;
}
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