Home | History | Annotate | Download | only in ext2fs
      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 <stdio.h>
     25 #include <string.h>
     26 #if HAVE_UNISTD_H
     27 #include <unistd.h>
     28 #endif
     29 
     30 #include "ext2_fs.h"
     31 #include "ext2fs.h"
     32 
     33 struct get_pathname_struct {
     34 	ext2_ino_t	search_ino;
     35 	ext2_ino_t	parent;
     36 	char		*name;
     37 	errcode_t	errcode;
     38 };
     39 
     40 #ifdef __TURBOC__
     41  #pragma argsused
     42 #endif
     43 static int get_pathname_proc(struct ext2_dir_entry *dirent,
     44 			     int	offset EXT2FS_ATTR((unused)),
     45 			     int	blocksize EXT2FS_ATTR((unused)),
     46 			     char	*buf EXT2FS_ATTR((unused)),
     47 			     void	*priv_data)
     48 {
     49 	struct get_pathname_struct	*gp;
     50 	errcode_t			retval;
     51 
     52 	gp = (struct get_pathname_struct *) priv_data;
     53 
     54 	if (((dirent->name_len & 0xFF) == 2) &&
     55 	    !strncmp(dirent->name, "..", 2))
     56 		gp->parent = dirent->inode;
     57 	if (dirent->inode == gp->search_ino) {
     58 		retval = ext2fs_get_mem((dirent->name_len & 0xFF) + 1,
     59 					&gp->name);
     60 		if (retval) {
     61 			gp->errcode = retval;
     62 			return DIRENT_ABORT;
     63 		}
     64 		strncpy(gp->name, dirent->name, (dirent->name_len & 0xFF));
     65 		gp->name[dirent->name_len & 0xFF] = '\0';
     66 		return DIRENT_ABORT;
     67 	}
     68 	return 0;
     69 }
     70 
     71 static errcode_t ext2fs_get_pathname_int(ext2_filsys fs, ext2_ino_t dir,
     72 					 ext2_ino_t ino, int maxdepth,
     73 					 char *buf, char **name)
     74 {
     75 	struct get_pathname_struct gp;
     76 	char	*parent_name = 0, *ret;
     77 	errcode_t	retval;
     78 
     79 	if (dir == ino) {
     80 		retval = ext2fs_get_mem(2, name);
     81 		if (retval)
     82 			return retval;
     83 		strcpy(*name, (dir == EXT2_ROOT_INO) ? "/" : ".");
     84 		return 0;
     85 	}
     86 
     87 	if (!dir || (maxdepth < 0)) {
     88 		retval = ext2fs_get_mem(4, name);
     89 		if (retval)
     90 			return retval;
     91 		strcpy(*name, "...");
     92 		return 0;
     93 	}
     94 
     95 	gp.search_ino = ino;
     96 	gp.parent = 0;
     97 	gp.name = 0;
     98 	gp.errcode = 0;
     99 
    100 	retval = ext2fs_dir_iterate(fs, dir, 0, buf, get_pathname_proc, &gp);
    101 	if (retval == EXT2_ET_NO_DIRECTORY) {
    102 		char tmp[32];
    103 
    104 		if (ino)
    105 			snprintf(tmp, sizeof(tmp), "<%u>/<%u>", dir, ino);
    106 		else
    107 			snprintf(tmp, sizeof(tmp), "<%u>", dir);
    108 		retval = ext2fs_get_mem(strlen(tmp)+1, name);
    109 		if (retval)
    110 			goto cleanup;
    111 		strcpy(*name, tmp);
    112 		return 0;
    113 	} else if (retval)
    114 		goto cleanup;
    115 	if (gp.errcode) {
    116 		retval = gp.errcode;
    117 		goto cleanup;
    118 	}
    119 
    120 	retval = ext2fs_get_pathname_int(fs, gp.parent, dir, maxdepth-1,
    121 					 buf, &parent_name);
    122 	if (retval)
    123 		goto cleanup;
    124 	if (!ino) {
    125 		*name = parent_name;
    126 		return 0;
    127 	}
    128 
    129 	if (gp.name)
    130 		retval = ext2fs_get_mem(strlen(parent_name)+strlen(gp.name)+2,
    131 					&ret);
    132 	else
    133 		retval = ext2fs_get_mem(strlen(parent_name)+5, &ret);
    134 	if (retval)
    135 		goto cleanup;
    136 
    137 	ret[0] = 0;
    138 	if (parent_name[1])
    139 		strcat(ret, parent_name);
    140 	strcat(ret, "/");
    141 	if (gp.name)
    142 		strcat(ret, gp.name);
    143 	else
    144 		strcat(ret, "???");
    145 	*name = ret;
    146 	retval = 0;
    147 
    148 cleanup:
    149 	ext2fs_free_mem(&parent_name);
    150 	ext2fs_free_mem(&gp.name);
    151 	return retval;
    152 }
    153 
    154 errcode_t ext2fs_get_pathname(ext2_filsys fs, ext2_ino_t dir, ext2_ino_t ino,
    155 			      char **name)
    156 {
    157 	char	*buf;
    158 	errcode_t	retval;
    159 
    160 	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
    161 
    162 	retval = ext2fs_get_mem(fs->blocksize, &buf);
    163 	if (retval)
    164 		return retval;
    165 	if (dir == ino)
    166 		ino = 0;
    167 	retval = ext2fs_get_pathname_int(fs, dir, ino, 32, buf, name);
    168 	ext2fs_free_mem(&buf);
    169 	return retval;
    170 
    171 }
    172