Ejemplo n.º 1
0
static int linear_search_in_dir_item(struct cpu_key *key,
				     struct reiserfs_dir_entry *de,
				     const char *name, int namelen)
{
	struct reiserfs_de_head *deh = de->de_deh;
	int retval;
	int i;

	i = de->de_entry_num;

	if (i == I_ENTRY_COUNT(de->de_ih) ||
	    GET_HASH_VALUE(deh_offset(deh + i)) !=
	    GET_HASH_VALUE(cpu_key_k_offset(key))) {
		i--;
	}

	RFALSE(de->de_deh != B_I_DEH(de->de_bh, de->de_ih),
	       "vs-7010: array of entry headers not found");

	deh += i;

	for (; i >= 0; i--, deh--) {
		if (GET_HASH_VALUE(deh_offset(deh)) !=
		    GET_HASH_VALUE(cpu_key_k_offset(key))) {
			// hash value does not match, no need to check whole name
			return NAME_NOT_FOUND;
		}

		/* mark, that this generation number is used */
		if (de->de_gen_number_bit_string)
			set_bit(GET_GENERATION_NUMBER(deh_offset(deh)),
				de->de_gen_number_bit_string);

		// calculate pointer to name and namelen
		de->de_entry_num = i;
		set_de_name_and_namelen(de);

		if ((retval =
		     reiserfs_match(de, name, namelen)) != NAME_NOT_FOUND) {
			// de's de_name, de_namelen, de_recordlen are set. Fill the rest:

			// key of pointed object
			set_de_object_key(de);

			store_de_entry_key(de);

			// retval can be NAME_FOUND or NAME_FOUND_INVISIBLE
			return retval;
		}
	}

	if (GET_GENERATION_NUMBER(le_ih_k_offset(de->de_ih)) == 0)
		/* we have reached left most entry in the node. In common we
		   have to go to the left neighbor, but if generation counter
		   is 0 already, we know for sure, that there is no name with
		   the same hash value */
		// FIXME: this work correctly only because hash value can not
		// be 0. Btw, in case of Yura's hash it is probably possible,
		// so, this is a bug
		return NAME_NOT_FOUND;

	RFALSE(de->de_item_num,
	       "vs-7015: two diritems of the same directory in one node?");

	return GOTO_PREVIOUS_ITEM;
}
Ejemplo n.º 2
0
/*
 * de's de_bh, de_ih, de_deh, de_item_num, de_entry_num are set already
 * Used when hash collisions exist
 */
static int
linear_search_in_dir_item(struct cpu_key *key, struct reiserfs_dir_entry *de,
    const char *name, int namelen)
{
	int i;
	int retval;
	struct reiserfs_de_head * deh = de->de_deh;

	i = de->de_entry_num;

	if (i == I_ENTRY_COUNT(de->de_ih) ||
	    GET_HASH_VALUE(deh_offset(deh + i)) !=
	    GET_HASH_VALUE(cpu_key_k_offset(key))) {
		i--;
	}

	/*RFALSE( de->de_deh != B_I_DEH (de->de_bh, de->de_ih),
	  "vs-7010: array of entry headers not found");*/

	deh += i;

	for (; i >= 0; i--, deh--) {
		if (GET_HASH_VALUE(deh_offset(deh)) !=
		    GET_HASH_VALUE(cpu_key_k_offset(key))) {
			/*
			 * Hash value does not match, no need to check
			 * whole name
			 */
			reiserfs_log(LOG_DEBUG, "name `%s' not found\n", name);
			return (NAME_NOT_FOUND);
		}

		/* Mark that this generation number is used */
		if (de->de_gen_number_bit_string)
			set_bit(GET_GENERATION_NUMBER(deh_offset(deh)),
			    (unsigned long *)de->de_gen_number_bit_string);

		/* Calculate pointer to name and namelen */
		de->de_entry_num = i;
		set_de_name_and_namelen(de);

		if ((retval = reiserfs_match(de, name, namelen)) !=
		    NAME_NOT_FOUND) {
			/*
			 * de's de_name, de_namelen, de_recordlen are set.
			 * Fill the rest:
			 */
			/* key of pointed object */
			set_de_object_key(de);
			store_de_entry_key(de);

			/* retval can be NAME_FOUND or NAME_FOUND_INVISIBLE */
			reiserfs_log(LOG_DEBUG,
			    "reiserfs_match answered `%d'\n",
			    retval);
			return (retval);
		}
	}

	if (GET_GENERATION_NUMBER(le_ih_k_offset(de->de_ih)) == 0)
		/*
		 * We have reached left most entry in the node. In common
		 * we have to go to the left neighbor, but if generation
		 * counter is 0 already, we know for sure, that there is
		 * no name with the same hash value
		 */
		/* FIXME: this work correctly only because hash value can
		 * not be 0. Btw, in case of Yura's hash it is probably
		 * possible, so, this is a bug
		 */
		return (NAME_NOT_FOUND);

	/*RFALSE(de->de_item_num,
	    "vs-7015: two diritems of the same directory in one node?");*/

	return (GOTO_PREVIOUS_ITEM);
}