[PATCH] AOSP: erofs-utils: fix sub directory prefix path in canned fs_config

[Gao Xiang]

On Tue, Dec 22, 2020 at 05:13:40PM +0800, Gao Xiang wrote:

...

> > > +		fspath = erofs_fspath(path);
> > 
> > lib/inode.c:688:10: error: assigning to 'char *' from 'const char *' discards...
> >                 fspath = erofs_fspath(path);
> >                        ^ ~~~~~~~~~~~~~~~~~~
> > 
> > -           fspath = erofs_fspath(path);
> > +         fspath = (char *)erofs_fspath(path);
> 
> oops, I think it can be modified as a temporary workaround, will submit a formal
> patch after verification.
> 
> > 
> > 
> > > +	else if (asprintf(&fspath, "%s/%s", cfg.mount_point,
> > > +			  erofs_fspath(path)) <= 0)
> > 
> > The argument of path will be root directory. And canned fs_config for root directory as
> > below:
> > 
> > 0 0 755 selabel=u:object_r:rootfs:s0 capabilities=0x0
> > 
> > So, cannot add mount point to root directory for canned fs_config. And what about non-canned
> > fs_config?
> 
> Not quite sure what you mean. For non-canned fs_config, we didn't observed any strange
> before (I ported to cuttlefish and hikey960 with boot success, also as I mentioned before
> some other vendors already use it.)
> 
> I think the following commit is only useful for squashfs since its (non)root inode
> workflows are different, so need to add in two difference place. But mkfs.erofs is not.
> https://android.googlesource.com/platform/external/squashfs-tools/+/85a6bc1e52bb911f195c5dc0890717913938c2d1%5E%21/#F0
> 
> For root inode is erofs, I think erofs_fspath(path) would return "", so that case
> is included as well.... Am I missing something?

Also I don't find any special handling logic in make_ext4fs for root inode
https://android.googlesource.com/platform/system/extras/+/refs/heads/oreo-release/ext4_utils/make_ext4fs.c#229

Actually I think the squashfs commit above might be wrong if "--mount-point" is
specified if my understanding is correct. Anyway, could you help verify it in advance?

Thanks,
Gao Xiang

> 
> Thanks,
> Gao Xiang
> 
> > 
> > Thx.