mirror of
https://github.com/urbit/shrub.git
synced 2024-12-15 04:22:48 +03:00
83 lines
2.1 KiB
Plaintext
83 lines
2.1 KiB
Plaintext
|
:: |base64: flexible base64 encoding for little-endian atoms
|
||
|
|
::
|
||
|
|
:: pad: include padding when encoding, require when decoding
|
||
|
|
:: url: use url-safe characters '-' for '+' and '_' for '/'
|
||
|
|
::
|
||
|
|
=+ [pad=& url=|]
|
||
|
|
|%
|
||
|
|
:: +en:base64: encode +octs to base64 cord
|
||
|
|
::
|
||
|
|
++ en
|
||
|
|
|= inp=octs
|
||
|
|
^- cord
|
||
|
|
:: dif: offset from 3-byte block
|
||
|
|
::
|
||
|
|
=/ dif=@ud (~(dif fo 3) 0 p.inp)
|
||
|
|
:: dap: reversed, 3-byte block-aligned input
|
||
|
|
::
|
||
|
|
=/ dap=@ux (lsh 3 dif (rev 3 inp))
|
||
|
|
=/ cha
|
||
|
|
?: url
|
||
|
|
'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_'
|
||
|
|
'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'
|
||
|
|
%- crip
|
||
|
|
%- flop
|
||
|
|
%+ weld
|
||
|
|
?.(pad ~ (reap dif '='))
|
||
|
|
%+ slag dif
|
||
|
|
|- ^- tape
|
||
|
|
?: =(0x0 dap) ~
|
||
|
|
=/ d (end 3 3 dap)
|
||
|
|
:* (cut 3 [(cut 0 [0 6] d) 1] cha)
|
||
|
|
(cut 3 [(cut 0 [6 6] d) 1] cha)
|
||
|
|
(cut 3 [(cut 0 [12 6] d) 1] cha)
|
||
|
|
(cut 3 [(cut 0 [18 6] d) 1] cha)
|
||
|
|
$(dap (rsh 3 3 dap))
|
||
|
|
==
|
||
|
|
:: +de:base64: decode base64 cord to (unit @)
|
||
|
|
::
|
||
|
|
++ de
|
||
|
|
|= a=cord
|
||
|
|
^- (unit octs)
|
||
|
|
(rush a parse)
|
||
|
|
:: +parse:base64: parse base64 cord to +octs
|
||
|
|
::
|
||
|
|
++ parse
|
||
|
|
=< ^- $-(nail (like octs))
|
||
|
|
%+ sear reduce
|
||
|
|
;~ plug
|
||
|
|
%- plus ;~ pose
|
||
|
|
(cook |=(a=@ (sub a 'A')) (shim 'A' 'Z'))
|
||
|
|
(cook |=(a=@ (sub a 'G')) (shim 'a' 'z'))
|
||
|
|
(cook |=(a=@ (add a 4)) (shim '0' '9'))
|
||
|
|
(cold 62 (just ?:(url '-' '+')))
|
||
|
|
(cold 63 (just ?:(url '_' '/')))
|
||
|
|
==
|
||
|
|
(stun 0^2 (cold %0 tis))
|
||
|
|
==
|
||
|
|
|%
|
||
|
|
:: +reduce:parse:base64: reduce, measure, and swap base64 digits
|
||
|
|
::
|
||
|
|
++ reduce
|
||
|
|
|= [dat=(list @) dap=(list @)]
|
||
|
|
^- (unit octs)
|
||
|
|
=/ lat (lent dat)
|
||
|
|
=/ lap (lent dap)
|
||
|
|
=/ dif (~(dif fo 4) 0 lat)
|
||
|
|
?: &(pad !=(dif lap))
|
||
|
|
:: padding required and incorrect
|
||
|
|
~&(%base-64-padding-err-one ~)
|
||
|
|
?: &(!pad !=(0 lap))
|
||
|
|
:: padding not required but present
|
||
|
|
~&(%base-64-padding-err-two ~)
|
||
|
|
=/ len (sub (mul 3 (div (add lat dif) 4)) dif)
|
||
|
|
:+ ~ len
|
||
|
|
%+ swp 3
|
||
|
|
:: %+ base 64
|
||
|
|
%+ roll
|
||
|
|
(weld dat (reap dif 0))
|
||
|
|
|=([p=@ q=@] (add p (mul 64 q)))
|
||
|
|
--
|
||
|
|
--
|
||
|
|
|