[PATCH U-BOOT 18/26] fs: btrfs: Implement btrfs_lookup_path()

Su Yue
2020-04-22T14:17:53Z

On Wed 22 Apr 2020 at 18:04, Marek Behun <marek.behun@nic.cz>
wrote:

> On Wed, 22 Apr 2020 17:46:25 +0800 Su Yue <Damenly_Su@gmx.com>
> wrote:
>
>> > + while (*cur != '\0') { + + cur =
>> > skip_current_directories(cur); + len =
>> > next_length(cur); + if (len > BTRFS_NAME_LEN) {
>> next_length() promises @len <= BTRFS_NAME_LEN, so the check is
>> trivial.
>

Okay.
> Hmm. This is a bug in next_length. I meant for next_length to
> return len > BTRFS_NAME_LEN in case of too long name. Thanks for
> noticing.
>
>> > + ret = btrfs_readlink(root, ino, target); +
>> > if (ret < 0) { + free(target); +
>> > return ret; + } + target[ret] = '\0';
>> It was done in btrfs_readlink() already.
>
> It is in old btrfs_readlink, but is it even after this patches?
> I don't see it in the new implementation.
>

You are right. The thing changed in the 17th patch.
btrfs_readlink()
doesn't set the null byte now.

--
Su
>> > +
>> > + ret = btrfs_lookup_path(root, ino, target, &next_root,
>> > + &next_ino, &next_type,
>> > + symlink_limit);
>>
>> Just notify gentlely this is a recursive call here. I don't know
>> whether uboot cares about stack things. But, recursion makes coding simpler :).
>
> It is limited by symlink_limit. Until somebody complains about stack
> issues I would like to keep it simple.