[ipxe-devel] [PATCH] [hci] Add setdirname command

[Andrew Bobulsky]

Ohhhhh okay, I get it now :)

I was a little confused by the name of the command itself.  It's
behavior then is to store the relative(?) path of a file from a boot
filename in a variable, if I've got that right.  Then given, for
example, the boot filename:
<protocol>://<server>/<pathX>/<pathY>/<boot-program>.<ext>

Then the command: setdirname _var ${<boot-filename-variable>}

Will take <pathX>/<pathY> and store it as the contents of ${_var} such
that "tftp://${next-server}/${_var}/" yields
"tftp://<server>/<pathX>/<pathY>/".

I chuckled a little bit because I've done this exact same thing a
dozen times with server-side scripting for HTTP booting, but having it
available directly to the client would certainly reduce the amount of
potentially obnoxious syntax errors I'm bound to generate recoding it
myself every time I do it ;)

Thanks for that clarification!  Clever and elegant indeed, sir :)

Cheers,
Andrew Bobulsky



On Fri, Jan 21, 2011 at 10:43 AM, Nils Carlson
<nils.carlson at ericsson.com> wrote:
> Hi Andrew,
>
> On Fri, 21 Jan 2011, Andrew Bobulsky wrote:
>
>> Hello Nils,
>>
>> Is this for defining the "TFTP Prefix:" one usually sees in a PXELINUX
>> boot or is it something else?  Is there a specific usage scenario for
>> it?
>>
>
> Well, typically on our boot server we have a little layout that looks like
> this:
>
> tftp://server/one/long/path/kernel
> tftp://server/one/long/path/initrd
> tftp://server/one/long/path/pxelinux.0
> tftp://server/one/long/path/pxelinux.cfg/default
>
> All we get from dhcp is
>
> filename=tftp://server/one/long/path/pxelinux.0
>
> and
>
> next-server=server
>
> pxelinux works relatively the path of filename.
>
> Now the server is a separate product, all we own on the server is our
> directory, and in an upgrade we can't change the dhcp server configuration,
> just the contents of the files. So we actually upload
> undionly.kkpxe with a symlink from pxelinux.0. The undionly.kkpxe has a
> built in script
>
> set use-cached 1
> dhcp net0
> setdirname _basedir ${filename}
> imgfetch -n bootscript
> tftp://${next-server}/${_basedir}/pxelinux.cfg/default
> imgload bootscript
> imgexec bootscript
>
> which lets us drop in a second script with whatever other parameters we need
> at tftp://server/one/long/path/pxelinux.cfg/default.
> All the time we keep the structure exactly the same as for the pxelinux
> case, so its quite elegant. And we can gradually replace pxelinux and
> eventually phase in newer features like booting from http, ftp or multicast
> or some such.
>
> /Nils
>
>
>
>> I'm just curious.  Not much of a developer here myself, but I'm
>> intrigued by something that helps keep PXELINUX strictly to the PXE
>> boot scenarios that specifically require it, rather than having to
>> bolt it on to solve funny netboot problems :)
>>
>
>
>
>
>> Thanks,
>> Andrew Bobulsky
>>
>>
>> On Fri, Jan 21, 2011 at 10:10 AM, Nils Carlson
>> <nils.carlson at ericsson.com> wrote:
>>>
>>> Add a setdirname command allowing us to retrieve the directory
>>> from a filename. Simplifies the replacement of pxelinux with
>>> ipxe.
>>>
>>> Signed-off-by: Nils Carlson <nils.carlson at ericsson.com>
>>> ---
>>>  src/hci/commands/nvo_cmd.c |   52
>>> ++++++++++++++++++++++++++++++++++++++++++++
>>>  1 files changed, 52 insertions(+), 0 deletions(-)
>>>
>>> diff --git a/src/hci/commands/nvo_cmd.c b/src/hci/commands/nvo_cmd.c
>>> index 3513c8d..784c14c 100644
>>> --- a/src/hci/commands/nvo_cmd.c
>>> +++ b/src/hci/commands/nvo_cmd.c
>>> @@ -16,6 +16,7 @@
>>>  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
>>>  */
>>>
>>> +#include <libgen.h>
>>>  #include <stdint.h>
>>>  #include <stdlib.h>
>>>  #include <stdio.h>
>>> @@ -178,6 +179,53 @@ static int clear_exec ( int argc, char **argv ) {
>>>        return 0;
>>>  }
>>>
>>> +/** "setdirname" options */
>>> +struct setdirname_options {};
>>> +
>>> +/** "setdirname" option list */
>>> +static struct option_descriptor setdirname_opts[] = {};
>>> +
>>> +/** "clear" command descriptor */
>>> +static struct command_descriptor setdirname_cmd =
>>> +       COMMAND_DESC ( struct setdirname_options, setdirname_opts, 2, 2,
>>> +                      "<setting> <path>", "" );
>>> +
>>> +/**
>>> + * "setdirname" command
>>> + *
>>> + * @v argc             Argument count
>>> + * @v argv             Argument list
>>> + * @ret rc             Return status code
>>> + */
>>> +static int setdirname_exec ( int argc, char **argv ) {
>>> +       struct setdirname_options opts;
>>> +       int rc;
>>> +       char buf[256];
>>> +       unsigned int len;
>>> +
>>> +       /* Parse options */
>>> +       if ( ( rc = parse_options ( argc, argv, &setdirname_cmd, &opts )
>>> ) != 0 )
>>> +               return rc;
>>> +
>>> +       len = strlen(argv[optind + 1]);
>>> +       if ( len > (sizeof(buf) - 1) ) {
>>> +               printf( "Path %s too long to save dirname\n", argv[optind
>>> + 1] );
>>> +               return 1;
>>> +       }
>>> +
>>> +       strncpy( buf, argv[optind + 1], sizeof(buf) - 1 );
>>> +
>>> +       if ( ( rc = storef_named_setting ( argv[optind], dirname(buf) ) )
>>> != 0 ) {
>>> +               printf ( "Could not set \"%s\" to dirname of \"%s\":
>>> %s\n",
>>> +                        argv[optind], argv[optind + 1], strerror ( rc )
>>> );
>>> +               return 1;
>>> +       }
>>> +
>>> +       return 0;
>>> +}
>>> +
>>> +
>>> +
>>>  /** Non-volatile option commands */
>>>  struct command nvo_commands[] __command = {
>>>        {
>>> @@ -192,4 +240,8 @@ struct command nvo_commands[] __command = {
>>>                .name = "clear",
>>>                .exec = clear_exec,
>>>        },
>>> +       {
>>> +               .name = "setdirname",
>>> +               .exec = setdirname_exec,
>>> +       },
>>>  };
>>> --
>>> 1.6.0.2
>>>
>>> _______________________________________________
>>> ipxe-devel mailing list
>>> ipxe-devel at lists.ipxe.org
>>> https://lists.ipxe.org/mailman/listinfo/ipxe-devel
>>>
>