[PATCH 00/18 v3] fs: add symlink and readlink support

[Sascha Hauer]

On Mon, Sep 03, 2012 at 12:04:09PM +0200, Jean-Christophe PLAGNIOL-VILLARD wrote:
> HI,
> 
> 	v3:
> 	 - fix support
> 	   mkdir mymount
> 	   mount -t ramfs none mymount/
> 	   ln /env/boot/net /mymount/link
> 
> 	 - addres comments
> 
> 	v2:
> 	 addres comments
> 
> please pull
> The following changes since commit b77300ac6c6bbbc7eac774ff0076c7c05d39735f:
> 
>   command/mount: add autodetection support (2012-08-21 18:53:00 +0800)
> 
> are available in the git repository at:
> 
>   git://git.jcrosoft.org/barebox.git tags/fs-symlink
> 
> for you to fetch changes up to dbae117ee78df0e4110db3a3acf4f9a8bee658d0:
> 
>   defautenv: add support of symlink (2012-09-03 17:57:23 +0800)
> 
> ----------------------------------------------------------------
> fs: add symlink and readlink support

Now we have:

> # mkdir ram
> # mount -t ramfs none /ram/
> # ln /env/boot/initrd ram/link
> # ls -l ram/
> lrwxrwxrwx         16 link -> /ram/env/boot/initrd
> # cat ram/link
> could not open ram/link: No such file or directory

The link should point to /env/boot/initrd instead.

This is probably related to your comment to nfs link support:

>> There is something wrong here. I do not understand what you do here, but
>> symlinks are not supposed to bash on them with dirname/basename until
>> you get something which fits your needs.
> here the issue is that on nfs you need to mount the correct path >otherwise you
> can not get the real file
>
> so we need to detect it and mount the correct path

This is wrong. If you put an absolute link somewhere and mount the
filesystem a somewhere else as NFS, then yes, the link will be broken if
the mountpoints do not match.

A symbolic link is basically just a text file, there is no magic behind
it that fixes pathes according to mount pathes.

Sascha


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