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 <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, *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)
 102                 goto cleanup;
 103         if (gp.errcode) {
 104                 retval = gp.errcode;
 105                 goto cleanup;
 106         }
 107
 108         retval = ext2fs_get_pathname_int(fs, gp.parent, dir, maxdepth-1,
 109                                          buf, &parent_name);
 110         if (retval)
 111                 goto cleanup;
 112         if (!ino) {
 113                 *name = parent_name;
 114                 return 0;
 115         }
 116
 117         if (gp.name)
 118                 retval = ext2fs_get_mem(strlen(parent_name)+strlen(gp.name)+2,
 119                                         &ret);
 120         else
 121                 retval = ext2fs_get_mem(strlen(parent_name)+5, &ret);
 122         if (retval)
 123                 goto cleanup;
 124
 125         ret[0] = 0;
 126         if (parent_name[1])
 127                 strcat(ret, parent_name);
 128         strcat(ret, "/");
 129         if (gp.name)
 130                 strcat(ret, gp.name);
 131         else
 132                 strcat(ret, "???");
 133         *name = ret;
 134         ext2fs_free_mem(&parent_name);
 135         retval = 0;
 136
 137 cleanup:
 138         if (gp.name)
 139                 ext2fs_free_mem(&gp.name);
 140         return retval;
 141 }
 142
 143 errcode_t ext2fs_get_pathname(ext2_filsys fs, ext2_ino_t dir, ext2_ino_t ino,
 144                               char **name)
 145 {
 146         char    *buf;
 147         errcode_t       retval;
 148
 149         EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
 150
 151         retval = ext2fs_get_mem(fs->blocksize, &buf);
 152         if (retval)
 153                 return retval;
 154         if (dir == ino)
 155                 ino = 0;
 156         retval = ext2fs_get_pathname_int(fs, dir, ino, 32, buf, name);
 157         ext2fs_free_mem(&buf);
 158         return retval;
 159
 160 }