get_pathname.c revision efc6f628e15de95bcd13e4f0ee223cb42115d520 
1/*
2 * get_pathname.c --- do directry/inode -> name translation
3 *
4 * Copyright (C) 1993, 1994, 1995 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 * 	ext2fs_get_pathname(fs, dir, ino, name)
12 *
13 * 	This function translates takes two inode numbers into a
14 * 	string, placing the result in <name>.  <dir> is the containing
15 * 	directory inode, and <ino> is the inode number itself.  If
16 * 	<ino> is zero, then ext2fs_get_pathname will return pathname
17 * 	of the the directory <dir>.
18 *
19 */
20
21#include <stdio.h>
22#include <string.h>
23#if HAVE_UNISTD_H
24#include <unistd.h>
25#endif
26
27#include "ext2_fs.h"
28#include "ext2fs.h"
29
30struct get_pathname_struct {
31	ext2_ino_t	search_ino;
32	ext2_ino_t	parent;
33	char		*name;
34	errcode_t	errcode;
35};
36
37#ifdef __TURBOC__
38 #pragma argsused
39#endif
40static int get_pathname_proc(struct ext2_dir_entry *dirent,
41			     int	offset EXT2FS_ATTR((unused)),
42			     int	blocksize EXT2FS_ATTR((unused)),
43			     char	*buf EXT2FS_ATTR((unused)),
44			     void	*priv_data)
45{
46	struct get_pathname_struct	*gp;
47	errcode_t			retval;
48
49	gp = (struct get_pathname_struct *) priv_data;
50
51	if (((dirent->name_len & 0xFF) == 2) &&
52	    !strncmp(dirent->name, "..", 2))
53		gp->parent = dirent->inode;
54	if (dirent->inode == gp->search_ino) {
55		retval = ext2fs_get_mem((dirent->name_len & 0xFF) + 1,
56					&gp->name);
57		if (retval) {
58			gp->errcode = retval;
59			return DIRENT_ABORT;
60		}
61		strncpy(gp->name, dirent->name, (dirent->name_len & 0xFF));
62		gp->name[dirent->name_len & 0xFF] = '\0';
63		return DIRENT_ABORT;
64	}
65	return 0;
66}
67
68static errcode_t ext2fs_get_pathname_int(ext2_filsys fs, ext2_ino_t dir,
69					 ext2_ino_t ino, int maxdepth,
70					 char *buf, char **name)
71{
72	struct get_pathname_struct gp;
73	char	*parent_name, *ret;
74	errcode_t	retval;
75
76	if (dir == ino) {
77		retval = ext2fs_get_mem(2, name);
78		if (retval)
79			return retval;
80		strcpy(*name, (dir == EXT2_ROOT_INO) ? "/" : ".");
81		return 0;
82	}
83
84	if (!dir || (maxdepth < 0)) {
85		retval = ext2fs_get_mem(4, name);
86		if (retval)
87			return retval;
88		strcpy(*name, "...");
89		return 0;
90	}
91
92	gp.search_ino = ino;
93	gp.parent = 0;
94	gp.name = 0;
95	gp.errcode = 0;
96
97	retval = ext2fs_dir_iterate(fs, dir, 0, buf, get_pathname_proc, &gp);
98	if (retval)
99		goto cleanup;
100	if (gp.errcode) {
101		retval = gp.errcode;
102		goto cleanup;
103	}
104
105	retval = ext2fs_get_pathname_int(fs, gp.parent, dir, maxdepth-1,
106					 buf, &parent_name);
107	if (retval)
108		goto cleanup;
109	if (!ino) {
110		*name = parent_name;
111		return 0;
112	}
113
114	if (gp.name)
115		retval = ext2fs_get_mem(strlen(parent_name)+strlen(gp.name)+2,
116					&ret);
117	else
118		retval = ext2fs_get_mem(strlen(parent_name)+5, &ret);
119	if (retval)
120		goto cleanup;
121
122	ret[0] = 0;
123	if (parent_name[1])
124		strcat(ret, parent_name);
125	strcat(ret, "/");
126	if (gp.name)
127		strcat(ret, gp.name);
128	else
129		strcat(ret, "???");
130	*name = ret;
131	ext2fs_free_mem(&parent_name);
132	retval = 0;
133
134cleanup:
135	if (gp.name)
136		ext2fs_free_mem(&gp.name);
137	return retval;
138}
139
140errcode_t ext2fs_get_pathname(ext2_filsys fs, ext2_ino_t dir, ext2_ino_t ino,
141			      char **name)
142{
143	char	*buf;
144	errcode_t	retval;
145
146	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
147
148	retval = ext2fs_get_mem(fs->blocksize, &buf);
149	if (retval)
150		return retval;
151	if (dir == ino)
152		ino = 0;
153	retval = ext2fs_get_pathname_int(fs, dir, ino, 32, buf, name);
154	ext2fs_free_mem(&buf);
155	return retval;
156
157}
158