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      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 
     30 struct 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
     40 static 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 
     68 static 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 
    134 cleanup:
    135 	if (gp.name)
    136 		ext2fs_free_mem(&gp.name);
    137 	return retval;
    138 }
    139 
    140 errcode_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