118 lines
2.4 KiB
C
118 lines
2.4 KiB
C
/*
|
|
* linux/fs/xiafs/symlink.c
|
|
*
|
|
* Copyright (C) Q. Frank Xia, 1993.
|
|
*
|
|
* Based on Linus' minix/symlink.c
|
|
* Copyright (C) Linus Torvalds, 1991, 1992.
|
|
*
|
|
* This software may be redistributed per Linux Copyright.
|
|
*/
|
|
|
|
#include <asm/segment.h>
|
|
|
|
#include <linux/errno.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/fs.h>
|
|
#include <linux/xia_fs.h>
|
|
#include <linux/stat.h>
|
|
|
|
static int
|
|
xiafs_readlink(struct inode *, char *, int);
|
|
|
|
static int
|
|
xiafs_follow_link(struct inode *, struct inode *, int, int, struct inode **);
|
|
|
|
/*
|
|
* symlinks can't do much...
|
|
*/
|
|
struct inode_operations xiafs_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 */
|
|
xiafs_readlink, /* readlink */
|
|
xiafs_follow_link, /* follow_link */
|
|
NULL, /* bmap */
|
|
NULL, /* truncate */
|
|
NULL /* permission */
|
|
};
|
|
|
|
static int xiafs_readlink(struct inode * inode, char * buffer, int buflen)
|
|
{
|
|
struct buffer_head * bh;
|
|
int i;
|
|
char c;
|
|
|
|
if (!S_ISLNK(inode->i_mode)) {
|
|
iput(inode);
|
|
return -EINVAL;
|
|
}
|
|
if (buflen > BLOCK_SIZE)
|
|
buflen = BLOCK_SIZE;
|
|
bh = xiafs_bread(inode, 0, 0);
|
|
if (!IS_RDONLY (inode)) {
|
|
inode->i_atime=CURRENT_TIME;
|
|
inode->i_dirt=1;
|
|
}
|
|
iput(inode);
|
|
if (!bh)
|
|
return 0;
|
|
for (i=0; i < buflen && (c=bh->b_data[i]); i++)
|
|
put_fs_byte(c, buffer++);
|
|
if (i < buflen-1)
|
|
put_fs_byte((char)0, buffer);
|
|
brelse(bh);
|
|
return i;
|
|
}
|
|
|
|
static int xiafs_follow_link(struct inode * dir, struct inode * inode,
|
|
int flag, int mode, struct inode ** res_inode)
|
|
{
|
|
int error;
|
|
struct buffer_head * bh;
|
|
|
|
*res_inode = NULL;
|
|
if (!dir) {
|
|
dir = current->root;
|
|
dir->i_count++;
|
|
}
|
|
if (!inode) {
|
|
iput(dir);
|
|
return -ENOENT;
|
|
}
|
|
if (!S_ISLNK(inode->i_mode)) {
|
|
iput(dir);
|
|
*res_inode = inode;
|
|
return 0;
|
|
}
|
|
if (!IS_RDONLY (inode)) {
|
|
inode->i_atime=CURRENT_TIME;
|
|
inode->i_dirt=1;
|
|
}
|
|
if (current->link_count > 5) {
|
|
iput(inode);
|
|
iput(dir);
|
|
return -ELOOP;
|
|
}
|
|
if (!(bh = xiafs_bread(inode, 0, 0))) {
|
|
iput(inode);
|
|
iput(dir);
|
|
return -EIO;
|
|
}
|
|
iput(inode);
|
|
current->link_count++;
|
|
error = open_namei(bh->b_data,flag,mode,res_inode,dir);
|
|
current->link_count--;
|
|
brelse(bh);
|
|
return error;
|
|
}
|
|
|
|
|
|
|