Re: [PATCH v5] probe: Support probing for GPT partition UUID with -g

[Jacob Kroon]

Hi Vladimir,

On Mon, May 13, 2019 at 10:11 PM Vladimir 'phcoder' Serbinenko
<address@hidden> wrote:
>
> Ideally the option shouldn't be specific to GPT as other partmaps also have 
> stable IDs. I think it's better not to have short option at all
>

Ok, I have some questions below.

> On Mon, 13 May 2019, 20:33 Jacob Kroon, <address@hidden> wrote:
>>
>> Linux supports root=PARTUUID=<partuuid> boot argument, so add
>> support for probing it. Compared to the fs UUID, the partition
>> UUID does not change when reformatting a partition.
>>
>> Signed-off-by: Jacob Kroon <address@hidden>
>> ---
>>  docs/grub.texi             |  2 +-
>>  grub-core/commands/probe.c | 34 ++++++++++++++++++++++++++++++++++
>>  2 files changed, 35 insertions(+), 1 deletion(-)
>>
>> Changes since v4:
>>  * Do endianess byte-swapping on the fly when formatting string
>>
>> diff --git a/docs/grub.texi b/docs/grub.texi
>> index 308b25074..d85818744 100644
>> --- a/docs/grub.texi
>> +++ b/docs/grub.texi
>> @@ -4771,7 +4771,7 @@ a rest.
>>  @node probe
>>  @subsection probe
>>
>> address@hidden Command probe address@hidden var] 
>> @option{--driver}|@option{--partmap}|@option{--fs}|@option{--fs-uuid}|@option{--label}
>>  device
>> address@hidden Command probe address@hidden var] 
>> @option{--driver}|@option{--partmap}|@option{--fs}|@option{--fs-uuid}|@option{--label}|@option{--part-uuid}
>>  device
>>  Retrieve device information. If option @option{--set} is given, assign 
>> result
>>  to variable @var{var}, otherwise print information on the screen.
>>  @end deffn
>> diff --git a/grub-core/commands/probe.c b/grub-core/commands/probe.c
>> index 95d272287..b26cbe2cc 100644
>> --- a/grub-core/commands/probe.c
>> +++ b/grub-core/commands/probe.c
>> @@ -24,6 +24,7 @@
>>  #include <grub/device.h>
>>  #include <grub/disk.h>
>>  #include <grub/partition.h>
>> +#include <grub/gpt_partition.h>
>>  #include <grub/net.h>
>>  #include <grub/fs.h>
>>  #include <grub/file.h>
>> @@ -45,6 +46,7 @@ static const struct grub_arg_option options[] =
>>      {"fs",             'f', 0, N_("Determine filesystem type."), 0, 0},
>>      {"fs-uuid",                'u', 0, N_("Determine filesystem UUID."), 0, 
>> 0},
>>      {"label",          'l', 0, N_("Determine filesystem label."), 0, 0},
>> +    {"part-uuid",      'g', 0, N_("Determine GPT partition UUID."), 0, 0},

Is "part-uuid" ok ? I guess I should remove "GPT" from the help text ?

I've seen both 0 and -1 being passed as short option, do they both
mean "no short option", or is there a preference which to use in this
case ?

/Jacob