Fixes <https://bugs.gnu.org/35582>.
Reported by sirgazil <sirgazil@zoho.com>.
Previously, leading zeros would be removed, leading to an "invalid"
UUID:
(uuid->string (uuid "00CA-050E" 'fat32))
⇒ "CA-50E"
(string->uuid "CA-50E" 'fat32)
⇒ #f
* gnu/system/uuid.scm (fat-uuid->string): Pad digits with zeros.
* tests/uuid.scm ("uuid, FAT32, leading zeros preserved"): New test.
* gnu/system/uuid.scm (uuid=?): New procedure.
* tests/uuid.scm ("uuid=?"): New test.
* gnu/build/file-systems.scm (partition-uuid-predicate)
(luks-partition-uuid-predicate): Use it instead of 'bytevector=?'.
* gnu/system/uuid.scm (%fat32-uuid-rx): New variable.
(string->fat32-uuid): New procedure.
(%uuid-parsers): Add it.
* tests/uuid.scm ("uuid, FAT32, format preserved"): New test.
Conceptually a UUID is just a bytevector. However, there's software out
there such as GRUB that relies on the string representation of different
UUID types (e.g., the string representation of DCE UUIDs differs from
that of ISO-9660 UUIDs, even if they are actually bytevectors of the
same length). This new <uuid> record type allows us to preserve
information about the type of UUID so we can eventually convert it to a
string using the right representation.
* gnu/system/uuid.scm (<uuid>): New record type.
(bytevector->uuid): New procedure.
(uuid): Return calls to 'make-uuid'.
(uuid->string): Rewrite using 'match-lambda*' to accept a single 'uuid?'
argument.
* gnu/bootloader/grub.scm (grub-root-search): Check for 'uuid?' instead
of 'bytevector?'.
* gnu/system.scm (bootable-kernel-arguments): Check whether ROOT-DEVICE
is 'uuid?'.
(read-boot-parameters): Use 'bytevector->uuid' when the
store device is a bytevector.
(read-boot-parameters-file): Check for 'uuid?' instead of 'bytevector?'.
(device->sexp): New procedure.
(operating-system-boot-parameters-file): Use it for 'root-device' and
'store'.
(operating-system-bootcfg): Remove conditional in definition of
'root-device'.
* gnu/system/file-systems.scm (file-system->spec): Check for 'uuid?' on
DEVICE and take its bytevector.
* gnu/system/mapped-devices.scm (open-luks-device): Likewise.
* gnu/system/vm.scm (iso9660-image): Call 'uuid-bytevector' for the
#:volume-uuid argument.
