reiserfs.c

F:worksip2440a board可启动u-boot-like.tar.gz F:worksip2440a board可启动u-boot-like.tar.gz

#endif /* REISERDEBUG */
	  if (key_nr == nr_item)
	    /* This is the last item in this block, set the next_key_nr to 0 */
	    INFO->next_key_nr[depth] = 0;

	  cache = read_tree_node (dc_block_number(&(DC (cache)[key_nr])), --depth);
	  if (! cache)
	    return 0;
	}
      while (depth > DISK_LEAF_NODE_LEVEL);

      ih = ITEMHEAD;
    }
 found:
  INFO->current_ih   = ih;
  INFO->current_item = &LEAF[__le16_to_cpu(ih->ih_item_location)];
#ifdef REISERDEBUG
  printf ("  new ih: key %d:%d:%d:%d version:%d\n",
	  __le32_to_cpu(INFO->current_ih->ih_key.k_dir_id),
	  __le32_to_cpu(INFO->current_ih->ih_key.k_objectid),
	  __le32_to_cpu(INFO->current_ih->ih_key.u.v1.k_offset),
	  __le32_to_cpu(INFO->current_ih->ih_key.u.v1.k_uniqueness),
	  __le16_to_cpu(INFO->current_ih->ih_version));
#endif /* REISERDEBUG */
  return 1;
}

/* preconditions: reiserfs_mount already executed, therefore
 *   INFO block is valid
 * returns: 0 if error (errnum is set),
 *   nonzero iff we were able to find the key successfully.
 * postconditions: on a nonzero return, the current_ih and
 *   current_item fields describe the key that equals the
 *   searched key.  INFO->next_key contains the next key after
 *   the searched key.
 * side effects: messes around with the cache.
 */
static int
search_stat (__u32 dir_id, __u32 objectid)
{
  char *cache;
  int depth;
  int nr_item;
  int i;
  struct item_head *ih;
#ifdef REISERDEBUG
  printf ("search_stat:\n  key %d:%d:0:0\n", dir_id, objectid);
#endif /* REISERDEBUG */

  depth = INFO->tree_depth;
  cache = ROOT;

  while (depth > DISK_LEAF_NODE_LEVEL)
    {
      struct key *key;
      nr_item = __le16_to_cpu(BLOCKHEAD (cache)->blk_nr_item);

      key = KEY (cache);

      for (i = 0; i < nr_item; i++)
	{
	  if (__le32_to_cpu(key->k_dir_id) > dir_id
	      || (__le32_to_cpu(key->k_dir_id) == dir_id
		  && (__le32_to_cpu(key->k_objectid) > objectid
		      || (__le32_to_cpu(key->k_objectid) == objectid
			  && (__le32_to_cpu(key->u.v1.k_offset)
			      | __le32_to_cpu(key->u.v1.k_uniqueness)) > 0))))
	    break;
	  key++;
	}

#ifdef REISERDEBUG
      printf ("  depth=%d, i=%d/%d\n", depth, i, nr_item);
#endif /* REISERDEBUG */
      INFO->next_key_nr[depth] = (i == nr_item) ? 0 : i+1;
      cache = read_tree_node (dc_block_number(&(DC (cache)[i])), --depth);
      if (! cache)
	return 0;
    }

  /* cache == LEAF */
  nr_item = __le16_to_cpu(BLOCKHEAD (LEAF)->blk_nr_item);
  ih = ITEMHEAD;
  for (i = 0; i < nr_item; i++)
    {
      if (__le32_to_cpu(ih->ih_key.k_dir_id) == dir_id
	  && __le32_to_cpu(ih->ih_key.k_objectid) == objectid
	  && __le32_to_cpu(ih->ih_key.u.v1.k_offset) == 0
	  && __le32_to_cpu(ih->ih_key.u.v1.k_uniqueness) == 0)
	{
#ifdef REISERDEBUG
	  printf ("  depth=%d, i=%d/%d\n", depth, i, nr_item);
#endif /* REISERDEBUG */
	  INFO->current_ih   = ih;
	  INFO->current_item = &LEAF[__le16_to_cpu(ih->ih_item_location)];
	  return 1;
	}
      ih++;
    }
  errnum = ERR_FSYS_CORRUPT;
  return 0;
}

int
reiserfs_read (char *buf, unsigned len)
{
  unsigned int blocksize;
  unsigned int offset;
  unsigned int to_read;
  char *prev_buf = buf;

#ifdef REISERDEBUG
  printf ("reiserfs_read: filepos=%d len=%d, offset=%Lx\n",
	  filepos, len, (__u64) IH_KEY_OFFSET (INFO->current_ih) - 1);
#endif /* REISERDEBUG */

  if (__le32_to_cpu(INFO->current_ih->ih_key.k_objectid) != INFO->fileinfo.k_objectid
      || IH_KEY_OFFSET (INFO->current_ih) > filepos + 1)
    {
      search_stat (INFO->fileinfo.k_dir_id, INFO->fileinfo.k_objectid);
      goto get_next_key;
    }

  while (! errnum)
    {
      if (__le32_to_cpu(INFO->current_ih->ih_key.k_objectid) != INFO->fileinfo.k_objectid) {
	break;
      }

      offset = filepos - IH_KEY_OFFSET (INFO->current_ih) + 1;
      blocksize = __le16_to_cpu(INFO->current_ih->ih_item_len);

#ifdef REISERDEBUG
      printf ("  loop: filepos=%d len=%d, offset=%d blocksize=%d\n",
	      filepos, len, offset, blocksize);
#endif /* REISERDEBUG */

      if (IH_KEY_ISTYPE(INFO->current_ih, TYPE_DIRECT)
	  && offset < blocksize)
	{
#ifdef REISERDEBUG
	  printf ("direct_read: offset=%d, blocksize=%d\n",
		  offset, blocksize);
#endif /* REISERDEBUG */
	  to_read = blocksize - offset;
	  if (to_read > len)
	    to_read = len;

	  memcpy (buf, INFO->current_item + offset, to_read);
	  goto update_buf_len;
	}
      else if (IH_KEY_ISTYPE(INFO->current_ih, TYPE_INDIRECT))
	{
	  blocksize = (blocksize >> 2) << INFO->fullblocksize_shift;
#ifdef REISERDEBUG
	  printf ("indirect_read: offset=%d, blocksize=%d\n",
		  offset, blocksize);
#endif /* REISERDEBUG */

	  while (offset < blocksize)
	    {
	      __u32 blocknr = __le32_to_cpu(((__u32 *) INFO->current_item)
		[offset >> INFO->fullblocksize_shift]);
	      int blk_offset = offset & (INFO->blocksize-1);
	      to_read = INFO->blocksize - blk_offset;
	      if (to_read > len)
		to_read = len;

	      /* Journal is only for meta data.  Data blocks can be read
	       * directly without using block_read
	       */
	      reiserfs_devread (blocknr << INFO->blocksize_shift,
				blk_offset, to_read, buf);
	    update_buf_len:
	      len -= to_read;
	      buf += to_read;
	      offset += to_read;
	      filepos += to_read;
	      if (len == 0)
		goto done;
	    }
	}
    get_next_key:
      next_key ();
    }
 done:
  return errnum ? 0 : buf - prev_buf;
}


/* preconditions: reiserfs_mount already executed, therefore
 *   INFO block is valid
 * returns: 0 if error, nonzero iff we were able to find the file successfully
 * postconditions: on a nonzero return, INFO->fileinfo contains the info
 *   of the file we were trying to look up, filepos is 0 and filemax is
 *   the size of the file.
 */
static int
reiserfs_dir (char *dirname)
{
  struct reiserfs_de_head *de_head;
  char *rest, ch;
  __u32 dir_id, objectid, parent_dir_id = 0, parent_objectid = 0;
#ifndef STAGE1_5
  int do_possibilities = 0;
#endif /* ! STAGE1_5 */
  char linkbuf[PATH_MAX];	/* buffer for following symbolic links */
  int link_count = 0;
  int mode;

  dir_id = REISERFS_ROOT_PARENT_OBJECTID;
  objectid = REISERFS_ROOT_OBJECTID;

  while (1)
    {
#ifdef REISERDEBUG
      printf ("dirname=%s\n", dirname);
#endif /* REISERDEBUG */

      /* Search for the stat info first. */
      if (! search_stat (dir_id, objectid))
	return 0;

#ifdef REISERDEBUG
       printf ("sd_mode=%x sd_size=%d\n",
	       stat_data_v1(INFO->current_ih) ? sd_v1_mode((struct stat_data_v1 *) INFO->current_item) :
						sd_v2_mode((struct stat_data *) (INFO->current_item)),
	       stat_data_v1(INFO->current_ih) ? sd_v1_size((struct stat_data_v1 *) INFO->current_item) :
						sd_v2_size((struct stat_data *) INFO->current_item)
	      );

#endif /* REISERDEBUG */
      mode = stat_data_v1(INFO->current_ih) ?
	       sd_v1_mode((struct stat_data_v1 *) INFO->current_item) :
	       sd_v2_mode((struct stat_data *) INFO->current_item);

      /* If we've got a symbolic link, then chase it. */
      if (S_ISLNK (mode))
	{
	  unsigned int len;
	  if (++link_count > MAX_LINK_COUNT)
	    {
	      errnum = ERR_SYMLINK_LOOP;
	      return 0;
	    }

	  /* Get the symlink size. */
	  filemax = stat_data_v1(INFO->current_ih) ?
		     sd_v1_size((struct stat_data_v1 *) INFO->current_item) :
		     sd_v2_size((struct stat_data *) INFO->current_item);

	  /* Find out how long our remaining name is. */
	  len = 0;
	  while (dirname[len] && !isspace (dirname[len]))
	    len++;

	  if (filemax + len > sizeof (linkbuf) - 1)
	    {
	      errnum = ERR_FILELENGTH;
	      return 0;
	    }

	  /* Copy the remaining name to the end of the symlink data.
	     Note that DIRNAME and LINKBUF may overlap! */
	  memmove (linkbuf + filemax, dirname, len+1);

	  INFO->fileinfo.k_dir_id = dir_id;
	  INFO->fileinfo.k_objectid = objectid;
	  filepos = 0;
	  if (! next_key ()
	      || reiserfs_read (linkbuf, filemax) != filemax)
	    {
	      if (! errnum)
		errnum = ERR_FSYS_CORRUPT;
	      return 0;
	    }

#ifdef REISERDEBUG
	  printf ("symlink=%s\n", linkbuf);
#endif /* REISERDEBUG */

	  dirname = linkbuf;
	  if (*dirname == '/')
	    {
	      /* It's an absolute link, so look it up in root. */
	      dir_id = REISERFS_ROOT_PARENT_OBJECTID;
	      objectid = REISERFS_ROOT_OBJECTID;
	    }
	  else
	    {
	      /* Relative, so look it up in our parent directory. */
	      dir_id   = parent_dir_id;
	      objectid = parent_objectid;
	    }

	  /* Now lookup the new name. */
	  continue;
	}

      /* if we have a real file (and we're not just printing possibilities),
	 then this is where we want to exit */

      if (! *dirname || isspace (*dirname))
	{
	  if (! S_ISREG (mode))
	    {
	      errnum = ERR_BAD_FILETYPE;
	      return 0;
	    }

	  filepos = 0;
	  filemax = stat_data_v1(INFO->current_ih) ?
		      sd_v1_size((struct stat_data_v1 *) INFO->current_item) :
		      sd_v2_size((struct stat_data *) INFO->current_item);
#if 0
	  /* If this is a new stat data and size is > 4GB set filemax to
	   * maximum
	   */
	  if (__le16_to_cpu(INFO->current_ih->ih_version) == ITEM_VERSION_2
	      && sd_size_hi((struct stat_data *) INFO->current_item) > 0)
	    filemax = 0xffffffff;
#endif
	  INFO->fileinfo.k_dir_id = dir_id;
	  INFO->fileinfo.k_objectid = objectid;
	  return next_key ();
	}

      /* continue with the file/directory name interpretation */
      while (*dirname == '/')
	dirname++;
      if (! S_ISDIR (mode))
	{
	  errnum = ERR_BAD_FILETYPE;
	  return 0;
	}
      for (rest = dirname; (ch = *rest) && ! isspace (ch) && ch != '/'; rest++);
      *rest = 0;

# ifndef STAGE1_5
      if (print_possibilities && ch != '/')
	do_possibilities = 1;
# endif /* ! STAGE1_5 */

      while (1)
	{
	  char *name_end;
	  int num_entries;

	  if (! next_key ())
	    return 0;
#ifdef REISERDEBUG
	  printf ("ih: key %d:%d:%d:%d version:%d\n",
		  __le32_to_cpu(INFO->current_ih->ih_key.k_dir_id),
		  __le32_to_cpu(INFO->current_ih->ih_key.k_objectid),
		  __le32_to_cpu(INFO->current_ih->ih_key.u.v1.k_offset),
		  __le32_to_cpu(INFO->current_ih->ih_key.u.v1.k_uniqueness),
		  __le16_to_cpu(INFO->current_ih->ih_version));
#endif /* REISERDEBUG */

	  if (__le32_to_cpu(INFO->current_ih->ih_key.k_objectid) != objectid)
	    break;

	  name_end = INFO->current_item + __le16_to_cpu(INFO->current_ih->ih_item_len);
	  de_head = (struct reiserfs_de_head *) INFO->current_item;
	  num_entries = __le16_to_cpu(INFO->current_ih->u.ih_entry_count);
	  while (num_entries > 0)
	    {
	      char *filename = INFO->current_item + deh_location(de_head);
	      char  tmp = *name_end;
	      if ((deh_state(de_head) & DEH_Visible))
		{
		  int cmp;
		  /* Directory names in ReiserFS are not null
		   * terminated.  We write a temporary 0 behind it.
		   * NOTE: that this may overwrite the first block in
		   * the tree cache.  That doesn't hurt as long as we
		   * don't call next_key () in between.
		   */
		  *name_end = 0;
		  cmp = substring (dirname, filename);
		  *name_end = tmp;
# ifndef STAGE1_5
		  if (do_possibilities)
		    {
		      if (cmp <= 0)
			{
			  char fn[PATH_MAX];
			  struct fsys_reiser_info info_save;

			  if (print_possibilities > 0)
			    print_possibilities = -print_possibilities;
			  *name_end = 0;
			  strcpy(fn, filename);
			  *name_end = tmp;

			  /* If NAME is "." or "..", do not count it.  */
			  if (strcmp (fn, ".") != 0 && strcmp (fn, "..") != 0) {
			    memcpy(&info_save, INFO, sizeof(struct fsys_reiser_info));
			    search_stat (deh_dir_id(de_head), deh_objectid(de_head));
			    sd_print_item(INFO->current_ih, INFO->current_item);
			    printf(" %s\n", fn);
			    search_stat (dir_id, objectid);
			    memcpy(INFO, &info_save, sizeof(struct fsys_reiser_info));
			  }
			}
		    }
		  else
# endif /* ! STAGE1_5 */
		    if (cmp == 0)
		      goto found;
		}
	      /* The beginning of this name marks the end of the next name.
	       */
	      name_end = filename;
	      de_head++;
	      num_entries--;
	    }
	}

# ifndef STAGE1_5
      if (print_possibilities < 0)
	return 1;
# endif /* ! STAGE1_5 */

      errnum = ERR_FILE_NOT_FOUND;
      *rest = ch;
      return 0;

    found:
      *rest = ch;
      dirname = rest;

      parent_dir_id = dir_id;
      parent_objectid = objectid;
      dir_id = deh_dir_id(de_head);
      objectid = deh_objectid(de_head);
    }
}

/*
 * U-Boot interface functions
 */

/*
 * List given directory
 *
 * RETURN: 0 - OK, else grub_error_t errnum
 */
int
reiserfs_ls (char *dirname)
{
	char *dir_slash;
	int res;

	errnum = 0;
	dir_slash = malloc(strlen(dirname) + 1);
	if (dir_slash == NULL) {
		return ERR_NUMBER_OVERFLOW;
	}
	strcpy(dir_slash, dirname);
	/* add "/" to the directory name */
	strcat(dir_slash, "/");

	print_possibilities = 1;
	res = reiserfs_dir (dir_slash);
	free(dir_slash);
	if (!res || errnum) {
		return errnum;
	}

	return 0;
}

/*
 * Open file for reading
 *
 * RETURN: >0 - OK, size of opened file
 *         <0 - ERROR  -grub_error_t errnum
 */
int
reiserfs_open (char *filename)
{
	/* open the file */
	errnum = 0;
	print_possibilities = 0;
	if (!reiserfs_dir (filename) || errnum) {
		return -errnum;
	}
	return filemax;
}

#endif /* CFG_CMD_REISER */