dir.c

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			    rlen, ufs_get_de_namlen(sb, de));
	
	return (error_msg == NULL ? 1 : 0);
}

struct ufs_dir_entry *ufs_dotdot(struct inode *dir, struct buffer_head **p)
{
	int err;
	struct buffer_head *bh = ufs_bread (dir, 0, 0, &err);
	struct ufs_dir_entry *res = NULL;

	if (bh) {
		res = (struct ufs_dir_entry *) bh->b_data;
		res = (struct ufs_dir_entry *)((char *)res +
			fs16_to_cpu(dir->i_sb, res->d_reclen));
	}
	*p = bh;
	return res;
}
ino_t ufs_inode_by_name(struct inode * dir, struct dentry *dentry)
{
	ino_t res = 0;
	struct ufs_dir_entry * de;
	struct buffer_head *bh;

	de = ufs_find_entry (dentry, &bh);
	if (de) {
		res = fs32_to_cpu(dir->i_sb, de->d_ino);
		brelse(bh);
	}
	return res;
}

void ufs_set_link(struct inode *dir, struct ufs_dir_entry *de,
		struct buffer_head *bh, struct inode *inode)
{
	dir->i_version = ++event;
	de->d_ino = cpu_to_fs32(dir->i_sb, inode->i_ino);
	mark_buffer_dirty(bh);
	if (IS_SYNC(dir)) {
		ll_rw_block (WRITE, 1, &bh);
		wait_on_buffer(bh);
	}
	brelse (bh);
}

/*
 *	ufs_add_entry()
 *
 * adds a file entry to the specified directory, using the same
 * semantics as ufs_find_entry(). It returns NULL if it failed.
 */
int ufs_add_link(struct dentry *dentry, struct inode *inode)
{
	struct super_block * sb;
	struct ufs_sb_private_info * uspi;
	unsigned long offset;
	unsigned fragoff;
	unsigned short rec_len;
	struct buffer_head * bh;
	struct ufs_dir_entry * de, * de1;
	struct inode *dir = dentry->d_parent->d_inode;
	const char *name = dentry->d_name.name;
	int namelen = dentry->d_name.len;
	int err;

	UFSD(("ENTER, name %s, namelen %u\n", name, namelen))
	
	sb = dir->i_sb;
	uspi = sb->u.ufs_sb.s_uspi;

	if (!namelen)
		return -EINVAL;
	bh = ufs_bread (dir, 0, 0, &err);
	if (!bh)
		return err;
	rec_len = UFS_DIR_REC_LEN(namelen);
	offset = 0;
	de = (struct ufs_dir_entry *) bh->b_data;
	while (1) {
		if ((char *)de >= UFS_SECTOR_SIZE + bh->b_data) {
			fragoff = offset & ~uspi->s_fmask;
			if (fragoff != 0 && fragoff != UFS_SECTOR_SIZE)
				ufs_error (sb, "ufs_add_entry", "internal error"
					" fragoff %u", fragoff);
			if (!fragoff) {
				brelse (bh);
				bh = ufs_bread (dir, offset >> sb->s_blocksize_bits, 1, &err);
				if (!bh)
					return err;
			}
			if (dir->i_size <= offset) {
				if (dir->i_size == 0) {
					brelse(bh);
					return -ENOENT;
				}
				de = (struct ufs_dir_entry *) (bh->b_data + fragoff);
				de->d_ino = 0;
				de->d_reclen = cpu_to_fs16(sb, UFS_SECTOR_SIZE);
				ufs_set_de_namlen(sb, de, 0);
				dir->i_size = offset + UFS_SECTOR_SIZE;
				mark_inode_dirty(dir);
			} else {
				de = (struct ufs_dir_entry *) bh->b_data;
			}
		}
		if (!ufs_check_dir_entry ("ufs_add_entry", dir, de, bh, offset)) {
			brelse (bh);
			return -ENOENT;
		}
		if (ufs_match(sb, namelen, name, de)) {
			brelse (bh);
			return -EEXIST;
		}
		if (de->d_ino == 0 && fs16_to_cpu(sb, de->d_reclen) >= rec_len)
			break;
			
		if (fs16_to_cpu(sb, de->d_reclen) >=
		     UFS_DIR_REC_LEN(ufs_get_de_namlen(sb, de)) + rec_len)
			break;
		offset += fs16_to_cpu(sb, de->d_reclen);
		de = (struct ufs_dir_entry *) ((char *) de + fs16_to_cpu(sb, de->d_reclen));
	}

	if (de->d_ino) {
		de1 = (struct ufs_dir_entry *) ((char *) de +
			UFS_DIR_REC_LEN(ufs_get_de_namlen(sb, de)));
		de1->d_reclen =
			cpu_to_fs16(sb, fs16_to_cpu(sb, de->d_reclen) -
				UFS_DIR_REC_LEN(ufs_get_de_namlen(sb, de)));
		de->d_reclen =
			cpu_to_fs16(sb, UFS_DIR_REC_LEN(ufs_get_de_namlen(sb, de)));
		de = de1;
	}
	de->d_ino = 0;
	ufs_set_de_namlen(sb, de, namelen);
	memcpy (de->d_name, name, namelen + 1);
	de->d_ino = cpu_to_fs32(sb, inode->i_ino);
	ufs_set_de_type(sb, de, inode->i_mode);
	mark_buffer_dirty(bh);
	if (IS_SYNC(dir)) {
		ll_rw_block (WRITE, 1, &bh);
		wait_on_buffer (bh);
	}
	brelse (bh);
	dir->i_mtime = dir->i_ctime = CURRENT_TIME;
	dir->i_version = ++event;
	mark_inode_dirty(dir);

	UFSD(("EXIT\n"))
	return 0;
}

/*
 * ufs_delete_entry deletes a directory entry by merging it with the
 * previous entry.
 */
int ufs_delete_entry (struct inode * inode, struct ufs_dir_entry * dir,
	struct buffer_head * bh )
	
{
	struct super_block * sb;
	struct ufs_dir_entry * de, * pde;
	unsigned i;
	
	UFSD(("ENTER\n"))

	sb = inode->i_sb;
	i = 0;
	pde = NULL;
	de = (struct ufs_dir_entry *) bh->b_data;
	
	UFSD(("ino %u, reclen %u, namlen %u, name %s\n",
		fs32_to_cpu(sb, de->d_ino),
		fs16to_cpu(sb, de->d_reclen),
		ufs_get_de_namlen(sb, de), de->d_name))

	while (i < bh->b_size) {
		if (!ufs_check_dir_entry ("ufs_delete_entry", inode, de, bh, i)) {
			brelse(bh);
			return -EIO;
		}
		if (de == dir)  {
			if (pde)
				fs16_add(sb, &pde->d_reclen,
					fs16_to_cpu(sb, dir->d_reclen));
			dir->d_ino = 0;
			inode->i_version = ++event;
			inode->i_ctime = inode->i_mtime = CURRENT_TIME;
			mark_inode_dirty(inode);
			mark_buffer_dirty(bh);
			if (IS_SYNC(inode)) {
				ll_rw_block(WRITE, 1, &bh);
				wait_on_buffer(bh);
			}
			brelse(bh);
			UFSD(("EXIT\n"))
			return 0;
		}
		i += fs16_to_cpu(sb, de->d_reclen);
		if (i == UFS_SECTOR_SIZE) pde = NULL;
		else pde = de;
		de = (struct ufs_dir_entry *)
		    ((char *) de + fs16_to_cpu(sb, de->d_reclen));
		if (i == UFS_SECTOR_SIZE && de->d_reclen == 0)
			break;
	}
	UFSD(("EXIT\n"))
	brelse(bh);
	return -ENOENT;
}

int ufs_make_empty(struct inode * inode, struct inode *dir)
{
	struct super_block * sb = dir->i_sb;
	struct buffer_head * dir_block;
	struct ufs_dir_entry * de;
	int err;

	dir_block = ufs_bread (inode, 0, 1, &err);
	if (!dir_block)
		return err;

	inode->i_blocks = sb->s_blocksize / UFS_SECTOR_SIZE;
	de = (struct ufs_dir_entry *) dir_block->b_data;
	de->d_ino = cpu_to_fs32(sb, inode->i_ino);
	ufs_set_de_type(sb, de, inode->i_mode);
	ufs_set_de_namlen(sb, de, 1);
	de->d_reclen = cpu_to_fs16(sb, UFS_DIR_REC_LEN(1));
	strcpy (de->d_name, ".");
	de = (struct ufs_dir_entry *)
		((char *)de + fs16_to_cpu(sb, de->d_reclen));
	de->d_ino = cpu_to_fs32(sb, dir->i_ino);
	ufs_set_de_type(sb, de, dir->i_mode);
	de->d_reclen = cpu_to_fs16(sb, UFS_SECTOR_SIZE - UFS_DIR_REC_LEN(1));
	ufs_set_de_namlen(sb, de, 2);
	strcpy (de->d_name, "..");
	mark_buffer_dirty(dir_block);
	brelse (dir_block);
	mark_inode_dirty(inode);
	return 0;
}

/*
 * routine to check that the specified directory is empty (for rmdir)
 */
int ufs_empty_dir (struct inode * inode)
{
	struct super_block * sb;
	unsigned long offset;
	struct buffer_head * bh;
	struct ufs_dir_entry * de, * de1;
	int err;
	
	sb = inode->i_sb;

	if (inode->i_size < UFS_DIR_REC_LEN(1) + UFS_DIR_REC_LEN(2) ||
	    !(bh = ufs_bread (inode, 0, 0, &err))) {
	    	ufs_warning (inode->i_sb, "empty_dir",
			      "bad directory (dir #%lu) - no data block",
			      inode->i_ino);
		return 1;
	}
	de = (struct ufs_dir_entry *) bh->b_data;
	de1 = (struct ufs_dir_entry *)
		((char *)de + fs16_to_cpu(sb, de->d_reclen));
	if (fs32_to_cpu(sb, de->d_ino) != inode->i_ino || de1->d_ino == 0 ||
	     strcmp (".", de->d_name) || strcmp ("..", de1->d_name)) {
	    	ufs_warning (inode->i_sb, "empty_dir",
			      "bad directory (dir #%lu) - no `.' or `..'",
			      inode->i_ino);
		return 1;
	}
	offset = fs16_to_cpu(sb, de->d_reclen) + fs16_to_cpu(sb, de1->d_reclen);
	de = (struct ufs_dir_entry *)
		((char *)de1 + fs16_to_cpu(sb, de1->d_reclen));
	while (offset < inode->i_size ) {
		if (!bh || (void *) de >= (void *) (bh->b_data + sb->s_blocksize)) {
			brelse (bh);
			bh = ufs_bread (inode, offset >> sb->s_blocksize_bits, 1, &err);
	 		if (!bh) {
				ufs_error (sb, "empty_dir",
					    "directory #%lu contains a hole at offset %lu",
					    inode->i_ino, offset);
				offset += sb->s_blocksize;
				continue;
			}
			de = (struct ufs_dir_entry *) bh->b_data;
		}
		if (!ufs_check_dir_entry ("empty_dir", inode, de, bh, offset)) {
			brelse (bh);
			return 1;
		}
		if (de->d_ino) {
			brelse (bh);
			return 0;
		}
		offset += fs16_to_cpu(sb, de->d_reclen);
		de = (struct ufs_dir_entry *)
			((char *)de + fs16_to_cpu(sb, de->d_reclen));
	}
	brelse (bh);
	return 1;
}

struct file_operations ufs_dir_operations = {
	read:		generic_read_dir,
	readdir:	ufs_readdir,
	fsync:		file_fsync,
};