Syslinux - Jun 2013 - [5.10] PXE + dhcp opts 209, 210 and path issues in tftp/http

On Wed, 12 Jun, at 05:01:13PM, Ady wrote:
> Perhaps the following is just a crazy idea... How about no 
> path-separator in the cfg file, and instead use multiple PATH 
> directives for each path in the cfg file?
> 
> Instead of the previous:
> PATH first_path:2nd_path
> 
> now just use:
> PATH first_path
> PATH 2nd_path
You can actually do this already - multiple PATH directives are
concatenated. But I think there's still value in allowing users to
specify multiple entries with one PATH.

-- 
Matt Fleming, Intel Open Source Technology Center

> On Wed, 12 Jun, at 05:01:13PM, Ady wrote:
> > Perhaps the following is just a crazy idea... How about no 
> > path-separator in the cfg file, and instead use multiple PATH 
> > directives for each path in the cfg file?
> > 
> > Instead of the previous:
> > PATH first_path:2nd_path
> > 
> > now just use:
> > PATH first_path
> > PATH 2nd_path
> 
> You can actually do this already - multiple PATH directives are
> concatenated. But I think there's still value in allowing users to
> specify multiple entries with one PATH.
> 
> -- 
> Matt Fleming, Intel Open Source Technology Center
> 
Yes, I know I can use multiple PATH directives. I shall emphasize my 
point in a better way.

What I mean is, to discard the possibility to write multiple paths in 
the same PATH directive. The path-separator in the cfg file would be 
more accurately described as "path-ending", which would be either LF, 
CR, or any combination of LF and CR in any order.

In other words, multiple paths would need multiple PATH directives in 
separated lines, and their priority would be established by the order 
in which they are written in the cfg file. I don't think it is such a 
big deal for the final user. Instead of using the "previous"
":",
just start a new line with a new PATH directive. Discard the 
"path-separator" concept from the PATH directive for the final user.

As I attempted to express in my previous email, I don't know if 
imposing LF and/or CR as "path-ending" (restricting the syntax
"to
one path per PATH directive line") would actually solve anything or 
whether at least would reduce potential collisions (":",
";", etc.).

If it simplifies code maintenance, I think in this case it would not 
be a big problem for users. The cfg file and the directive syntax 
would still be simple enough.

Best Regards,
Ady.

On Wed, 2013-06-12 at 15:40 +0100, Matt Fleming wrote:
> On Wed, 12 Jun, at 05:01:13PM, Ady wrote:
> > Perhaps the following is just a crazy idea... How about no 
> > path-separator in the cfg file, and instead use multiple PATH 
> > directives for each path in the cfg file?
> > 
> > Instead of the previous:
> > PATH first_path:2nd_path
> > 
> > now just use:
> > PATH first_path
> > PATH 2nd_path
> 
> You can actually do this already - multiple PATH directives are
> concatenated. But I think there's still value in allowing users to
> specify multiple entries with one PATH.
Right, so assuming you switch to the linked-list model, PATH needs to
split its argument on colons and add each of the resulting directories
to the path.  Then the present problem can be solved by introducing a
new directive which does _not_ split its argument.

-- Jeff

On Wed, 12 Jun, at 11:43:24AM, Jeffrey Hutzelman wrote:
> Right, so assuming you switch to the linked-list model, PATH needs to
> split its argument on colons and add each of the resulting directories
> to the path.  Then the present problem can be solved by introducing a
> new directive which does _not_ split its argument.
 
Hmm... actually a new directive that allows a more complex path entry
syntax might be a better idea - something along the lines of,

  URLPATH http://www.foo.com/bar/ ftp://baz.org/ ::/tftp/ /bin/

That way, we can completely redefine the syntax as something more
conducive to urls.

-- 
Matt Fleming, Intel Open Source Technology Center