[edk2-devel] Need clarification about UEFI Strings

[Ayush Singh]

Ok, Thanks for all the help.

On Tue, Jun 7, 2022 at 3:28 PM Pedro Falcato <pedro.falcato at gmail.com> wrote:
>
> I'd say that it depends. But 98% of the strings you'll find in UEFI (including APIs) are UCS-2 CHAR16 strings.
>
> On Tue, Jun 7, 2022 at 9:19 AM Ayush Singh <ayushdevel1325 at gmail.com> wrote:
>>
>> Thanks, Pedro,
>>
>> However, according to the specs, it is possible to construct ASCII
>> Strings as well. So when would ASCII Strings be used over normal UCS-2
>> Strings?
>>
>> Ayush Singh
>>
>> On Tue, Jun 7, 2022 at 1:13 PM Pedro Falcato <pedro.falcato at gmail.com> wrote:
>> >
>> > Hi Ayush,
>> >
>> > In the latest UEFI 2.9 spec, it's specified under 2.3.1 that CHAR8 strings/characters are (usually) ASCII, and CHAR16 strings/characters are (usually) UCS-2 (*not* UTF-16).
>> >
>> > On Tue, Jun 7, 2022 at 7:02 AM Ayush Singh <ayushdevel1325 at gmail.com> wrote:
>> >>
>> >> Hello everyone, I am trying to write an implementation for UEFI
>> >> strings in Rust and just wanted clarification about some things.
>> >>
>> >> Are UEFI Strings UTF-16 encoded? I have looked at some previous Rust
>> >> implementations for this and it seems UEFI does not support the whole
>> >> UTF-16 but rather only UCS-2
>> >> (https://en.wikipedia.org/wiki/Universal_Coded_Character_Set) which is
>> >> a subset of UTF-16.
>> >>
>> >> There is also something called WTF-8
>> >> (https://en.wikipedia.org/wiki/UTF-8#WTF-8) which Rust uses to
>> >> represent OsStrings in Windows which is supposed to use UTF-16 (?).
>> >>
>> >> Anyway, if someone can point me to the resources/specifications of
>> >> UEFI Strings, it would be a great help.
>> >>
>> >> Ayush Singh
>> >>
>> >>
>> >> 
>> >>
>> >>
>> >
>> >
>> > --
>> > Pedro Falcato
>
>
>
> --
> Pedro Falcato


-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.
View/Reply Online (#90289): https://edk2.groups.io/g/devel/message/90289
Mute This Topic: https://groups.io/mt/91595087/1813853
Group Owner: devel+owner at edk2.groups.io
Unsubscribe: https://edk2.groups.io/g/devel/unsub [edk2-devel-archive at redhat.com]
-=-=-=-=-=-=-=-=-=-=-=-