get_pathname.c revision d1154eb460efe588eaed3d439c1caaca149fa362 
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 Library
8 * General Public License, version 2.
9 * %End-Header%
10 */
11
12/*
13 *
14 * 	ext2fs_get_pathname(fs, dir, ino, name)
15 *
16 * 	This function translates takes two inode numbers into a
17 * 	string, placing the result in <name>.  <dir> is the containing
18 * 	directory inode, and <ino> is the inode number itself.  If
19 * 	<ino> is zero, then ext2fs_get_pathname will return pathname
20 * 	of the the directory <dir>.
21 *
22 */
23
24#include "config.h"
25#include <stdio.h>
26#include <string.h>
27#if HAVE_UNISTD_H
28#include <unistd.h>
29#endif
30
31#include "ext2_fs.h"
32#include "ext2fs.h"
33
34struct get_pathname_struct {
35	ext2_ino_t	search_ino;
36	ext2_ino_t	parent;
37	char		*name;
38	errcode_t	errcode;
39};
40
41#ifdef __TURBOC__
42 #pragma argsused
43#endif
44static int get_pathname_proc(struct ext2_dir_entry *dirent,
45			     int	offset EXT2FS_ATTR((unused)),
46			     int	blocksize EXT2FS_ATTR((unused)),
47			     char	*buf EXT2FS_ATTR((unused)),
48			     void	*priv_data)
49{
50	struct get_pathname_struct	*gp;
51	errcode_t			retval;
52
53	gp = (struct get_pathname_struct *) priv_data;
54
55	if (((dirent->name_len & 0xFF) == 2) &&
56	    !strncmp(dirent->name, "..", 2))
57		gp->parent = dirent->inode;
58	if (dirent->inode == gp->search_ino) {
59		retval = ext2fs_get_mem((dirent->name_len & 0xFF) + 1,
60					&gp->name);
61		if (retval) {
62			gp->errcode = retval;
63			return DIRENT_ABORT;
64		}
65		strncpy(gp->name, dirent->name, (dirent->name_len & 0xFF));
66		gp->name[dirent->name_len & 0xFF] = '\0';
67		return DIRENT_ABORT;
68	}
69	return 0;
70}
71
72static errcode_t ext2fs_get_pathname_int(ext2_filsys fs, ext2_ino_t dir,
73					 ext2_ino_t ino, int maxdepth,
74					 char *buf, char **name)
75{
76	struct get_pathname_struct gp;
77	char	*parent_name, *ret;
78	errcode_t	retval;
79
80	if (dir == ino) {
81		retval = ext2fs_get_mem(2, name);
82		if (retval)
83			return retval;
84		strcpy(*name, (dir == EXT2_ROOT_INO) ? "/" : ".");
85		return 0;
86	}
87
88	if (!dir || (maxdepth < 0)) {
89		retval = ext2fs_get_mem(4, name);
90		if (retval)
91			return retval;
92		strcpy(*name, "...");
93		return 0;
94	}
95
96	gp.search_ino = ino;
97	gp.parent = 0;
98	gp.name = 0;
99	gp.errcode = 0;
100
101	retval = ext2fs_dir_iterate(fs, dir, 0, buf, get_pathname_proc, &gp);
102	if (retval)
103		goto cleanup;
104	if (gp.errcode) {
105		retval = gp.errcode;
106		goto cleanup;
107	}
108
109	retval = ext2fs_get_pathname_int(fs, gp.parent, dir, maxdepth-1,
110					 buf, &parent_name);
111	if (retval)
112		goto cleanup;
113	if (!ino) {
114		*name = parent_name;
115		return 0;
116	}
117
118	if (gp.name)
119		retval = ext2fs_get_mem(strlen(parent_name)+strlen(gp.name)+2,
120					&ret);
121	else
122		retval = ext2fs_get_mem(strlen(parent_name)+5, &ret);
123	if (retval)
124		goto cleanup;
125
126	ret[0] = 0;
127	if (parent_name[1])
128		strcat(ret, parent_name);
129	strcat(ret, "/");
130	if (gp.name)
131		strcat(ret, gp.name);
132	else
133		strcat(ret, "???");
134	*name = ret;
135	ext2fs_free_mem(&parent_name);
136	retval = 0;
137
138cleanup:
139	if (gp.name)
140		ext2fs_free_mem(&gp.name);
141	return retval;
142}
143
144errcode_t ext2fs_get_pathname(ext2_filsys fs, ext2_ino_t dir, ext2_ino_t ino,
145			      char **name)
146{
147	char	*buf;
148	errcode_t	retval;
149
150	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
151
152	retval = ext2fs_get_mem(fs->blocksize, &buf);
153	if (retval)
154		return retval;
155	if (dir == ino)
156		ino = 0;
157	retval = ext2fs_get_pathname_int(fs, dir, ino, 32, buf, name);
158	ext2fs_free_mem(&buf);
159	return retval;
160
161}
162