1 /*
2 * unlink.c --- delete links in a ext2fs directory
3 *
4 * Copyright (C) 1993, 1994, 1997 Theodore Ts'o.
5 *
6 * %Begin-Header%
7 * This file may be redistributed under the terms of the GNU Public
8 * License.
9 * %End-Header%
10 */
11
12 #include <stdio.h>
13 #include <string.h>
14 #if HAVE_UNISTD_H
15 #include <unistd.h>
16 #endif
17
18 #include "ext2_fs.h"
19 #include "ext2fs.h"
20
21 struct link_struct {
22 const char *name;
23 int namelen;
24 ext2_ino_t inode;
25 int flags;
26 struct ext2_dir_entry *prev;
27 int done;
28 };
29
30 #ifdef __TURBOC__
31 #pragma argsused
32 #endif
unlink_proc(struct ext2_dir_entry * dirent,int offset,int blocksize EXT2FS_ATTR ((unused)),char * buf EXT2FS_ATTR ((unused)),void * priv_data)33 static int unlink_proc(struct ext2_dir_entry *dirent,
34 int offset,
35 int blocksize EXT2FS_ATTR((unused)),
36 char *buf EXT2FS_ATTR((unused)),
37 void *priv_data)
38 {
39 struct link_struct *ls = (struct link_struct *) priv_data;
40 struct ext2_dir_entry *prev;
41
42 prev = ls->prev;
43 ls->prev = dirent;
44
45 if (ls->name) {
46 if ((dirent->name_len & 0xFF) != ls->namelen)
47 return 0;
48 if (strncmp(ls->name, dirent->name, dirent->name_len & 0xFF))
49 return 0;
50 }
51 if (ls->inode) {
52 if (dirent->inode != ls->inode)
53 return 0;
54 } else {
55 if (!dirent->inode)
56 return 0;
57 }
58
59 if (offset)
60 prev->rec_len += dirent->rec_len;
61 else
62 dirent->inode = 0;
63 ls->done++;
64 return DIRENT_ABORT|DIRENT_CHANGED;
65 }
66
67 #ifdef __TURBOC__
68 #pragma argsused
69 #endif
ext2fs_unlink(ext2_filsys fs,ext2_ino_t dir,const char * name,ext2_ino_t ino,int flags EXT2FS_ATTR ((unused)))70 errcode_t ext2fs_unlink(ext2_filsys fs, ext2_ino_t dir,
71 const char *name, ext2_ino_t ino,
72 int flags EXT2FS_ATTR((unused)))
73 {
74 errcode_t retval;
75 struct link_struct ls;
76
77 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
78
79 if (!name && !ino)
80 return EXT2_ET_INVALID_ARGUMENT;
81
82 if (!(fs->flags & EXT2_FLAG_RW))
83 return EXT2_ET_RO_FILSYS;
84
85 ls.name = name;
86 ls.namelen = name ? strlen(name) : 0;
87 ls.inode = ino;
88 ls.flags = 0;
89 ls.done = 0;
90 ls.prev = 0;
91
92 retval = ext2fs_dir_iterate(fs, dir, DIRENT_FLAG_INCLUDE_EMPTY,
93 0, unlink_proc, &ls);
94 if (retval)
95 return retval;
96
97 return (ls.done) ? 0 : EXT2_ET_DIR_NO_SPACE;
98 }
99
100