1997-04-26 17:21:57 +04:00
|
|
|
/*
|
1997-04-29 20:17:09 +04:00
|
|
|
* link.c --- create links in a ext2fs directory
|
1997-04-26 17:21:57 +04:00
|
|
|
*
|
1997-04-29 20:17:09 +04:00
|
|
|
* Copyright (C) 1993, 1994 Theodore Ts'o.
|
|
|
|
*
|
|
|
|
* %Begin-Header%
|
|
|
|
* This file may be redistributed under the terms of the GNU Public
|
|
|
|
* License.
|
|
|
|
* %End-Header%
|
1997-04-26 17:21:57 +04:00
|
|
|
*/
|
|
|
|
|
|
|
|
#include <stdio.h>
|
|
|
|
#include <string.h>
|
1997-08-11 03:07:40 +04:00
|
|
|
#if HAVE_UNISTD_H
|
1997-04-26 17:21:57 +04:00
|
|
|
#include <unistd.h>
|
1997-08-11 03:07:40 +04:00
|
|
|
#endif
|
1997-04-26 17:21:57 +04:00
|
|
|
#include <stdlib.h>
|
1997-04-26 17:34:30 +04:00
|
|
|
|
1997-04-26 17:21:57 +04:00
|
|
|
#include <linux/ext2_fs.h>
|
|
|
|
|
|
|
|
#include "ext2fs.h"
|
|
|
|
|
|
|
|
struct link_struct {
|
|
|
|
const char *name;
|
|
|
|
int namelen;
|
|
|
|
ino_t inode;
|
|
|
|
int flags;
|
|
|
|
int done;
|
|
|
|
};
|
|
|
|
|
|
|
|
static int link_proc(struct ext2_dir_entry *dirent,
|
|
|
|
int offset,
|
|
|
|
int blocksize,
|
|
|
|
char *buf,
|
|
|
|
void *private)
|
|
|
|
{
|
|
|
|
struct link_struct *ls = (struct link_struct *) private;
|
|
|
|
struct ext2_dir_entry *next;
|
|
|
|
int rec_len;
|
|
|
|
int ret = 0;
|
|
|
|
|
|
|
|
rec_len = EXT2_DIR_REC_LEN(ls->namelen);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* See if the following directory entry (if any) is unused;
|
|
|
|
* if so, absorb it into this one.
|
|
|
|
*/
|
|
|
|
next = (struct ext2_dir_entry *) (buf + offset + dirent->rec_len);
|
|
|
|
if ((offset + dirent->rec_len < blocksize - 8) &&
|
|
|
|
(next->inode == 0) &&
|
|
|
|
(offset + dirent->rec_len + next->rec_len <= blocksize)) {
|
|
|
|
dirent->rec_len += next->rec_len;
|
|
|
|
ret = DIRENT_CHANGED;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* If the directory entry is used, see if we can split the
|
|
|
|
* directory entry to make room for the new name. If so,
|
|
|
|
* truncate it and return.
|
|
|
|
*/
|
|
|
|
if (dirent->inode) {
|
|
|
|
if (dirent->rec_len < (EXT2_DIR_REC_LEN(dirent->name_len) +
|
|
|
|
rec_len))
|
|
|
|
return ret;
|
|
|
|
rec_len = dirent->rec_len - EXT2_DIR_REC_LEN(dirent->name_len);
|
|
|
|
dirent->rec_len = EXT2_DIR_REC_LEN(dirent->name_len);
|
|
|
|
next = (struct ext2_dir_entry *) (buf + offset +
|
|
|
|
dirent->rec_len);
|
|
|
|
next->inode = 0;
|
|
|
|
next->name_len = 0;
|
|
|
|
next->rec_len = rec_len;
|
|
|
|
return DIRENT_CHANGED;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* If we get this far, then the directory entry is not used.
|
|
|
|
* See if we can fit the request entry in. If so, do it.
|
|
|
|
*/
|
|
|
|
if (dirent->rec_len < rec_len)
|
|
|
|
return ret;
|
|
|
|
dirent->inode = ls->inode;
|
|
|
|
dirent->name_len = ls->namelen;
|
|
|
|
strncpy(dirent->name, ls->name, ls->namelen);
|
|
|
|
|
|
|
|
ls->done++;
|
|
|
|
return DIRENT_ABORT|DIRENT_CHANGED;
|
|
|
|
}
|
|
|
|
|
|
|
|
errcode_t ext2fs_link(ext2_filsys fs, ino_t dir, const char *name, ino_t ino,
|
|
|
|
int flags)
|
|
|
|
{
|
|
|
|
errcode_t retval;
|
|
|
|
struct link_struct ls;
|
|
|
|
|
1997-04-26 17:34:30 +04:00
|
|
|
EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
|
|
|
|
|
1997-04-26 17:21:57 +04:00
|
|
|
if (!(fs->flags & EXT2_FLAG_RW))
|
|
|
|
return EXT2_ET_RO_FILSYS;
|
|
|
|
|
|
|
|
ls.name = name;
|
|
|
|
ls.namelen = name ? strlen(name) : 0;
|
|
|
|
ls.inode = ino;
|
|
|
|
ls.flags = 0;
|
|
|
|
ls.done = 0;
|
|
|
|
|
|
|
|
retval = ext2fs_dir_iterate(fs, dir, DIRENT_FLAG_INCLUDE_EMPTY,
|
|
|
|
0, link_proc, &ls);
|
|
|
|
if (retval)
|
|
|
|
return retval;
|
|
|
|
|
|
|
|
return (ls.done) ? 0 : EXT2_ET_DIR_NO_SPACE;
|
|
|
|
}
|