In the next commit we will implement a new checksum, codex32, which uses
the same encoding and HRP rules as bech32 and bech32m, but has a
substantially different checksum verification procedure. To minimize
duplicated code, we expose the character conversion in a new
bech32::internals module.
Co-authored-by: Luke Dashjr <luke-jr+git@utopios.org>
Github-Pull: #27351
Rebased-From: 7a57cda8e4461b1ac075251c945eaeb18f1edfd4
Replace ExpandHRP with a PreparePolynomialCoefficients function. Instead
of using a hardcoded value for the size of the array (90 in this case)
and a hardcoded value for the checksum, use the actual values vector and
define checksum size as a constexpr. Use the new CHECKSUM_SIZE
throughout instead 6.
Co-authored-by: Lőrinc <pap.lorinc@gmail.com>
Bech32(m) was defined with a 90 character limit so that certain
guarantees for error detection could be made for segwit addresses.
However, there is nothing about the encoding scheme itself that requires
a limit and in practice bech32(m) has been used without the 90 char
limit (e.g. lightning invoices).
Further, increasing the character limit doesn't do away with error
detection, it simply lessons the guarantees.
Model charlimit as an Enum, so that if a different address scheme is
using bech32(m), the character limit for that address scheme can be
used, rather than always using the 90 charlimit defined for segwit
addresses.
upate comment
Added are:
* Vector(arg1,arg2,arg3,...) constructs a vector with the specified
arguments as elements. The vector's type is derived from the
arguments. If some of the arguments are rvalue references, they
will be moved into place rather than copied (which can't be achieved
using list initialization).
* Cat(vector1,vector2) returns a concatenation of the two vectors,
efficiently moving elements when relevant.
Vector generalizes (and replaces) the Singleton function in
src/descriptor.cpp, and Cat replaces the Cat function in bech32.cpp
