lib/ext2fs/get_pathname.c

   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
  34 struct 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
  44 static 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
  72 static 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
 138 cleanup:
 139         if (gp.name)
 140                 ext2fs_free_mem(&gp.name);
 141         return retval;
 142 }
 143
 144 errcode_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 }