urbit/pkg/base-dev/lib/ethereum.hoon
2022-05-14 22:05:39 -07:00

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:: ethereum: utilities
::
=, ethereum-types
|%
:: deriving and using ethereum keys
::
++ key
|%
++ address-from-pub
=, keccak:crypto
|= pub=@
%+ end [3 20]
%+ keccak-256 64
(rev 3 64 pub)
::
++ address-from-prv
(cork pub-from-prv address-from-pub)
::
++ pub-from-prv
=, secp256k1:secp:crypto
|= prv=@
%- serialize-point
(priv-to-pub prv)
::
++ sign-typed-transaction
|= [tx=typed-transaction:rpc pk=@]
^- @ux
=- (cat 3 - -.tx)
?- -.tx
%0x0 (sign-transaction +.tx pk)
%0x2 (sign-transaction-1559 +.tx pk)
==
::
++ sign-transaction
=, crypto
|= [tx=transaction:rpc pk=@]
|^ ^- @ux
:: hash the raw transaction data
=/ hash=@
%- keccak-256:keccak
=+ dat=(encode chain-id.tx 0 0)
=+ wid=(met 3 dat)
[wid (rev 3 wid dat)]
:: sign transaction hash with private key
=+ (ecdsa-raw-sign:secp256k1:secp hash pk)
:: complete transaction is raw data, with r and s
:: taken from the signature, and v as per eip-155
(encode :(add (mul chain-id.tx 2) 35 v) r s)
::
++ encode
|= [v=@ r=@ s=@]
%+ encode:rlp %l
tx(to b+20^to.tx, chain-id [v r s ~])
--
::
++ sign-transaction-1559
=, crypto
|= [tx=transaction-1559:rpc pk=@]
|^ ^- @ux
=; hash=@
=+ (ecdsa-raw-sign:secp256k1:secp hash pk)
::NOTE we retrieve y's parity from the v value
(encode-1559 ~ (end 0 v) r s)
:: hash the raw transaction data including leading 0x2
%- keccak-256:keccak
=+ dat=(cat 3 (encode-1559 ~) 0x2)
=+ wid=(met 3 dat)
[wid (rev 3 wid dat)]
::
++ encode-1559
|= sig=(unit [y=@ r=@ s=@])
%+ encode:rlp %l
=, tx
:* chain-id
nonce
max-priority-gas-fee
max-gas-fee
gas
b+20^to
value
data
::
:- %l
%+ turn ~(tap by access-list)
|= [a=address b=(list @ux)]
l+~[b+20^a l+(turn b |=(c=@ux b+32^c))]
::
?~ sig ~
~[y r s]:u.sig
==
--
--
::
:: rlp en/decoding
::NOTE https://eth.wiki/en/fundamentals/rlp
::
++ rlp
|%
::NOTE rlp encoding doesn't really care about leading zeroes,
:: but because we need to disinguish between no-bytes zero
:: and one-byte zero (and also empty list) we end up with
:: this awful type...
+$ item
$@ @
$% [%l l=(list item)]
[%b b=byts]
==
:: +encode-atoms: encode list of atoms as a %l of %b items
::
++ encode-atoms ::NOTE deprecated
|= l=(list @)
^- @
(encode l+l)
::
++ encode
|= in=item
|^ ^- @
?- in
@
$(in [%b (met 3 in) in])
::
[%b *]
?: &(=(1 wid.b.in) (lte dat.b.in 0x7f))
dat.b.in
=- (can 3 ~[b.in [(met 3 -) -]])
(encode-length wid.b.in 0x80)
::
[%l *]
:: we +can because b+1^0x0 encodes to 0x00
::
=/ l=(list byts)
%+ turn l.in
|= ni=item
=+ (encode ni)
[(max 1 (met 3 -)) -]
%+ can 3
%- flop
=- [(met 3 -)^- l]
(encode-length (roll (turn l head) add) 0xc0)
==
::
++ encode-length
|= [len=@ off=@]
?: (lth len 56) (add len off)
=- (cat 3 len -)
:(add (met 3 len) off 55)
--
:: +decode-atoms: decode expecting a %l of %b items, producing atoms within
::
++ decode-atoms
|= dat=@
^- (list @)
=/ i=item (decode dat)
~| [%unexpected-data i]
?> ?=(%l -.i)
%+ turn l.i
|= i=item
~| [%unexpected-list i]
?> ?=(%b -.i)
dat.b.i
::
++ decode
|= dat=@
^- item
=/ bytes=(list @) (flop (rip 3 dat))
=? bytes ?=(~ bytes) ~[0]
|^ item:decode-head
::
++ decode-head
^- [done=@ud =item]
?~ bytes
~| %rlp-unexpected-end
!!
=* byt i.bytes
:: byte in 0x00-0x79 range encodes itself
::
?: (lte byt 0x79)
:- 1
[%b 1^byt]
:: byte in 0x80-0xb7 range encodes string length
::
?: (lte byt 0xb7)
=+ len=(sub byt 0x80)
:- +(len)
:- %b
len^(get-value 1 len)
:: byte in 0xb8-0xbf range encodes string length length
::
?: (lte byt 0xbf)
=+ led=(sub byt 0xb7)
=+ len=(get-value 1 led)
:- (add +(led) len)
:- %b
len^(get-value +(led) len)
:: byte in 0xc0-f7 range encodes list length
::
?: (lte byt 0xf7)
=+ len=(sub byt 0xc0)
:- +(len)
:- %l
%. len
decode-list(bytes (slag 1 `(list @)`bytes))
:: byte in 0xf8-ff range encodes list length length
::
?: (lte byt 0xff)
=+ led=(sub byt 0xf7)
=+ len=(get-value 1 led)
:- (add +(led) len)
:- %l
%. len
decode-list(bytes (slag +(led) `(list @)`bytes))
~| [%rip-not-bloq-3 `@ux`byt]
!!
::
++ decode-list
|= rem=@ud
^- (list item)
?: =(0 rem) ~
=+ ^- [don=@ud =item] ::TODO =/
decode-head
:- item
%= $
rem (sub rem don)
bytes (slag don bytes)
==
::
++ get-value
|= [at=@ud to=@ud]
^- @
(rep 3 (flop (swag [at to] bytes)))
--
--
::
:: abi en/decoding
::NOTE https://solidity.readthedocs.io/en/develop/abi-spec.html
::
++ abi
=> |%
:: solidity types. integer bitsizes ignored
++ etyp
$@ $? :: static
%address %bool
%int %uint
%real %ureal
:: dynamic
%bytes %string
==
$% :: static
[%bytes-n n=@ud]
:: dynamic
[%array-n t=etyp n=@ud]
[%array t=etyp]
==
::
:: solidity-style typed data. integer bitsizes ignored
++ data
$% [%address p=address]
[%string p=tape]
[%bool p=?]
[%int p=@sd]
[%uint p=@ud]
[%real p=@rs]
[%ureal p=@urs]
[%array-n p=(list data)]
[%array p=(list data)]
[%bytes-n p=octs] ::TODO just @, because context knows length?
[%bytes p=octs]
==
--
=, mimes:html
|%
:: encoding
::
++ encode-args
:: encode list of arguments.
::
|= das=(list data)
^- tape
(encode-data [%array-n das])
::
++ encode-data
:: encode typed data into ABI bytestring.
::
|= dat=data
^- tape
?+ -.dat
~| [%unsupported-type -.dat]
!!
::
%array-n
:: enc(X) = head(X[0]) ... head(X[k-1]) tail(X[0]) ... tail(X[k-1])
:: where head and tail are defined for X[i] being of a static type as
:: head(X[i]) = enc(X[i]) and tail(X[i]) = "" (the empty string), or as
:: head(X[i]) = enc(len( head(X[0])..head(X[k-1])
:: tail(X[0])..tail(X[i-1]) ))
:: and tail(X[i]) = enc(X[i]) otherwise.
::
:: so: if it's a static type, data goes in the head. if it's a dynamic
:: type, a reference goes into the head and data goes into the tail.
::
:: in the head, we first put a placeholder where references need to go.
=+ hol=(reap 64 'x')
=/ hes=(list tape)
%+ turn p.dat
|= d=data
?. (is-dynamic-type d) ^$(dat d)
hol
=/ tas=(list tape)
%+ turn p.dat
|= d=data
?. (is-dynamic-type d) ""
^$(dat d)
:: once we know the head and tail, we can fill in the references in head.
=- (weld nes `tape`(zing tas))
^- [@ud nes=tape]
=+ led=(lent (zing hes))
%+ roll hes
|= [t=tape i=@ud nes=tape]
:- +(i)
:: if no reference needed, just put the data.
?. =(t hol) (weld nes t)
:: calculate byte offset of data we need to reference.
=/ ofs=@ud
=- (div - 2) :: two hex digits per byte.
%+ add led :: count head, and
%- lent %- zing :: count all tail data
(scag i tas) :: preceding ours.
=+ ref=^$(dat [%uint ofs])
:: shouldn't hit this unless we're sending over 2gb of data?
~| [%weird-ref-lent (lent ref)]
?> =((lent ref) (lent hol))
(weld nes ref)
::
%array :: where X has k elements (k is assumed to be of type uint256):
:: enc(X) = enc(k) enc([X[1], ..., X[k]])
:: i.e. it is encoded as if it were an array of static size k, prefixed
:: with the number of elements.
%+ weld $(dat [%uint (lent p.dat)])
$(dat [%array-n p.dat])
::
%bytes-n
:: enc(X) is the sequence of bytes in X padded with zero-bytes to a
:: length of 32.
:: Note that for any X, len(enc(X)) is a multiple of 32.
~| [%bytes-n-too-long max=32 actual=p.p.dat]
?> (lte p.p.dat 32)
(pad-to-multiple (render-hex-bytes p.dat) 64 %right)
::
%bytes :: of length k (which is assumed to be of type uint256)
:: enc(X) = enc(k) pad_right(X), i.e. the number of bytes is encoded as a
:: uint256 followed by the actual value of X as a byte sequence, followed
:: by the minimum number of zero-bytes such that len(enc(X)) is a
:: multiple of 32.
%+ weld $(dat [%uint p.p.dat])
(pad-to-multiple (render-hex-bytes p.dat) 64 %right)
::
%string
:: enc(X) = enc(enc_utf8(X)), i.e. X is utf-8 encoded and this value is
:: interpreted as of bytes type and encoded further. Note that the length
:: used in this subsequent encoding is the number of bytes of the utf-8
:: encoded string, not its number of characters.
$(dat [%bytes (lent p.dat) (swp 3 (crip p.dat))])
::
%uint
:: enc(X) is the big-endian encoding of X, padded on the higher-order
:: (left) side with zero-bytes such that the length is a multiple of 32
:: bytes.
(pad-to-multiple (render-hex-bytes (as-octs p.dat)) 64 %left)
::
%bool
:: as in the uint8 case, where 1 is used for true and 0 for false
$(dat [%uint ?:(p.dat 1 0)])
::
%address
:: as in the uint160 case
$(dat [%uint `@ud`p.dat])
==
::
++ is-dynamic-type
|= a=data
?. ?=(%array-n -.a)
?=(?(%string %bytes %array) -.a)
&(!=((lent p.a) 0) (lien p.a is-dynamic-type))
::
:: decoding
::
++ decode-topics decode-arguments
::
++ decode-results
:: rex: string of hex bytes with leading 0x.
|* [rex=@t tys=(list etyp)]
=- (decode-arguments - tys)
%^ rut 9
(rsh [3 2] rex)
(curr rash hex)
::
++ decode-arguments
|* [wos=(list @) tys=(list etyp)]
=/ wos=(list @) wos :: get rid of tmi
=| win=@ud
=< (decode-from 0 tys)
|%
++ decode-from
|* [win=@ud tys=(list etyp)]
?~ tys !!
=- ?~ t.tys dat
[dat $(win nin, tys t.tys)]
(decode-one win ~[i.tys])
::
++ decode-one
::NOTE we take (list etyp) even though we only operate on
:: a single etyp as a workaround for urbit/arvo#673
|* [win=@ud tys=(list etyp)]
=- [nin dat]=- ::NOTE ^= regular form broken
?~ tys !!
=* typ i.tys
=+ wor=(snag win wos)
?+ typ
~| [%unsupported-type typ]
!!
::
?(%address %bool %uint) :: %int %real %ureal
:- +(win)
?- typ
%address `@ux`wor
%uint `@ud`wor
%bool =(1 wor)
==
::
%string
=+ $(tys ~[%bytes])
[nin (trip (swp 3 q.dat))]
::
%bytes
:- +(win)
:: find the word index of the actual data.
=/ lic=@ud (div wor 32)
:: learn the bytelength of the data.
=/ len=@ud (snag lic wos)
(decode-bytes-n +(lic) len)
::
[%bytes-n *]
:- (add win +((div (dec n.typ) 32)))
(decode-bytes-n win n.typ)
::
[%array *]
:- +(win)
:: find the word index of the actual data.
=. win (div wor 32)
:: read the elements from their location.
%- tail
%^ decode-array-n ~[t.typ] +(win)
(snag win wos)
::
[%array-n *]
(decode-array-n ~[t.typ] win n.typ)
==
::
++ decode-bytes-n
|= [fro=@ud bys=@ud]
^- octs
:: parse {bys} bytes from {fro}.
:- bys
%+ rsh
:- 3
=+ (mod bys 32)
?:(=(0 -) - (sub 32 -))
%+ rep 8
%- flop
=- (swag [fro -] wos)
+((div (dec bys) 32))
::
++ decode-array-n
::NOTE we take (list etyp) even though we only operate on
:: a single etyp as a workaround for urbit/arvo#673
::NOTE careful! produces lists without type info
=| res=(list)
|* [tys=(list etyp) fro=@ud len=@ud]
^- [@ud (list)]
?~ tys !!
?: =(len 0) [fro (flop `(list)`res)]
=+ (decode-one fro ~[i.tys]) :: [nin=@ud dat=*]
$(res ^+(res [dat res]), fro nin, len (dec len))
--
--
::
:: communicating with rpc nodes
::NOTE https://github.com/ethereum/wiki/wiki/JSON-RPC
::
++ rpc
:: types
::
=> =, abi
=, format
|%
:: raw call data
++ call-data
$: function=@t
arguments=(list data)
==
::
:: raw transaction data
+$ typed-transaction
$% [%0x0 transaction]
[%0x2 transaction-1559]
==
::
+$ transaction
$: nonce=@ud
gas-price=@ud
gas=@ud
to=address
value=@ud
data=@ux
chain-id=@ux
==
::
+$ transaction-1559
$: chain-id=@ux
nonce=@ud
max-priority-gas-fee=@ud
max-gas-fee=@ud
gas=@ud
to=address
value=@ud
data=@ux
access-list=(jar address @ux)
==
::
:: ethereum json rpc api
::
:: supported requests.
++ request
$% [%eth-block-number ~]
[%eth-call cal=call deb=block]
$: %eth-new-filter
fro=(unit block)
tob=(unit block)
adr=(list address)
top=(list ?(@ux (list @ux)))
==
[%eth-get-block-by-number bon=@ud txs=?]
[%eth-get-filter-logs fid=@ud]
$: %eth-get-logs
fro=(unit block)
tob=(unit block)
adr=(list address)
top=(list ?(@ux (list @ux)))
==
$: %eth-get-logs-by-hash
has=@
adr=(list address)
top=(list ?(@ux (list @ux)))
==
[%eth-get-filter-changes fid=@ud]
[%eth-get-transaction-by-hash txh=@ux]
[%eth-get-transaction-count adr=address =block]
[%eth-get-balance adr=address =block]
[%eth-get-transaction-receipt txh=@ux]
[%eth-send-raw-transaction dat=@ux]
==
::
::TODO clean up & actually use
++ response
$% ::TODO
[%eth-new-filter fid=@ud]
[%eth-get-filter-logs los=(list event-log)]
[%eth-get-logs los=(list event-log)]
[%eth-get-logs-by-hash los=(list event-log)]
[%eth-got-filter-changes los=(list event-log)]
[%eth-transaction-hash haz=@ux]
==
::
++ transaction-result
$: block-hash=(unit @ux)
block-number=(unit @ud)
transaction-index=(unit @ud)
from=@ux
to=(unit @ux)
input=@t
==
::
++ event-log
$: :: null for pending logs
$= mined %- unit
$: input=(unit @ux)
log-index=@ud
transaction-index=@ud
transaction-hash=@ux
block-number=@ud
block-hash=@ux
removed=?
==
::
address=@ux
data=@t
:: event data
::
:: For standard events, the first topic is the event signature
:: hash. For anonymous events, the first topic is the first
:: indexed argument.
:: Note that this does not support the "anonymous event with
:: zero topics" case. This has dubious usability, and using
:: +lest instead of +list saves a lot of ?~ checks.
::
topics=(lest @ux)
==
::
:: data for eth_call.
++ call
$: from=(unit address)
to=address
gas=(unit @ud)
gas-price=(unit @ud)
value=(unit @ud)
data=tape
==
::
:: minimum data needed to construct a read call
++ proto-read-request
$: id=(unit @t)
to=address
call-data
==
::
:: block to operate on.
++ block
$% [%number n=@ud]
[%label l=?(%earliest %latest %pending)]
==
--
::
:: logic
::
|%
++ encode-call
|= call-data
^- tape
::TODO should this check to see if the data matches the function signature?
=- :(weld "0x" - (encode-args arguments))
%+ scag 8
%+ render-hex-bytes 32
%- keccak-256:keccak:crypto
(as-octs:mimes:html function)
::
:: building requests
::
++ json-request
=, eyre
|= [url=purl jon=json]
^- hiss
:^ url %post
%- ~(gas in *math)
~['Content-Type'^['application/json']~]
(some (as-octt (en-json:html jon)))
:: +light-json-request: like json-request, but for %l
::
:: TODO: Exorcising +purl from our system is a much longer term effort;
:: get the current output types for now.
::
++ light-json-request
|= [url=purl:eyre jon=json]
^- request:http
::
:* %'POST'
(crip (en-purl:html url))
~[['content-type' 'application/json']]
(some (as-octt (en-json:html jon)))
==
::
++ batch-read-request
|= req=(list proto-read-request)
^- json
a+(turn req read-request)
::
++ read-request
|= proto-read-request
^- json
%+ request-to-json id
:+ %eth-call
^- call
[~ to ~ ~ ~ `tape`(encode-call function arguments)]
[%label %latest]
::
++ request-to-json
=, enjs:format
|= [riq=(unit @t) req=request]
^- json
%- pairs
=; r=[met=@t pas=(list json)]
::TODO should use request-to-json:rpc:jstd,
:: and probably (fall riq -.req)
:* jsonrpc+s+'2.0'
method+s+met.r
params+a+pas.r
::TODO would just jamming the req noun for id be a bad idea?
?~ riq ~
[id+s+u.riq]~
==
?- -.req
%eth-block-number
['eth_blockNumber' ~]
::
%eth-call
:- 'eth_call'
:~ (eth-call-to-json cal.req)
(block-to-json deb.req)
==
::
%eth-new-filter
:- 'eth_newFilter'
:_ ~
:- %o %- ~(gas by *(map @t json))
=- (murn - same)
^- (list (unit (pair @t json)))
:~ ?~ fro.req ~
`['fromBlock' (block-to-json u.fro.req)]
::
?~ tob.req ~
`['toBlock' (block-to-json u.tob.req)]
::
::NOTE tmi
?: =(0 (lent adr.req)) ~
:+ ~ 'address'
?: =(1 (lent adr.req)) (tape (address-to-hex (snag 0 adr.req)))
:- %a
(turn adr.req (cork address-to-hex tape))
::
?~ top.req ~
:+ ~ 'topics'
(topics-to-json top.req)
==
::
%eth-get-block-by-number
:- 'eth_getBlockByNumber'
:~ (tape (num-to-hex bon.req))
b+txs.req
==
::
%eth-get-filter-logs
['eth_getFilterLogs' (tape (num-to-hex fid.req)) ~]
::
%eth-get-logs
:- 'eth_getLogs'
:_ ~
:- %o %- ~(gas by *(map @t json))
=- (murn - same)
^- (list (unit (pair @t json)))
:~ ?~ fro.req ~
`['fromBlock' (block-to-json u.fro.req)]
::
?~ tob.req ~
`['toBlock' (block-to-json u.tob.req)]
::
?: =(0 (lent adr.req)) ~
:+ ~ 'address'
?: =(1 (lent adr.req)) (tape (address-to-hex (snag 0 adr.req)))
:- %a
(turn adr.req (cork address-to-hex tape))
::
?~ top.req ~
:+ ~ 'topics'
(topics-to-json top.req)
==
::
%eth-get-logs-by-hash
:- 'eth_getLogs'
:_ ~ :- %o
%- ~(gas by *(map @t json))
=- (murn - same)
^- (list (unit (pair @t json)))
:~ `['blockHash' (tape (transaction-to-hex has.req))]
::
?: =(0 (lent adr.req)) ~
:+ ~ 'address'
?: =(1 (lent adr.req)) (tape (address-to-hex (snag 0 adr.req)))
:- %a
(turn adr.req (cork address-to-hex tape))
::
?~ top.req ~
:+ ~ 'topics'
(topics-to-json top.req)
==
::
%eth-get-filter-changes
['eth_getFilterChanges' (tape (num-to-hex fid.req)) ~]
::
%eth-get-transaction-count
:- 'eth_getTransactionCount'
:~ (tape (address-to-hex adr.req))
(block-to-json block.req)
==
::
%eth-get-balance
:- 'eth_getBalance'
:~ (tape (address-to-hex adr.req))
(block-to-json block.req)
==
::
%eth-get-transaction-by-hash
['eth_getTransactionByHash' (tape (transaction-to-hex txh.req)) ~]
::
%eth-get-transaction-receipt
['eth_getTransactionReceipt' (tape (transaction-to-hex txh.req)) ~]
::
%eth-send-raw-transaction
['eth_sendRawTransaction' (tape (num-to-hex dat.req)) ~]
==
::
++ eth-call-to-json
=, enjs:format
|= cal=call
^- json
:- %o %- ~(gas by *(map @t json))
=- (murn - same)
^- (list (unit (pair @t json)))
:~ ?~ from.cal ~
`['from' (tape (address-to-hex u.from.cal))]
::
`['to' (tape (address-to-hex to.cal))]
::
?~ gas.cal ~
`['gas' (tape (num-to-hex u.gas.cal))]
::
?~ gas-price.cal ~
`['gasPrice' (tape (num-to-hex u.gas-price.cal))]
::
?~ value.cal ~
`['value' (tape (num-to-hex u.value.cal))]
::
?~ data.cal ~
`['data' (tape data.cal)]
==
::
++ block-to-json
|= dob=block
^- json
?- -.dob
%number s+(crip '0' 'x' ((x-co:co 1) n.dob))
%label s+l.dob
==
::
++ topics-to-json
|= tos=(list ?(@ux (list @ux)))
^- json
:- %a
=/ ttj
;: cork
(cury render-hex-bytes 32)
prefix-hex
tape:enjs:format
==
%+ turn tos
|= t=?(@ (list @))
?@ t
?: =(0 t) ~
(ttj `@`t)
a+(turn t ttj)
::
:: parsing responses
::
::TODO ++ parse-response |= json ^- response
::
++ parse-hex-result
|= j=json
^- @
?> ?=(%s -.j)
(hex-to-num p.j)
::
++ parse-eth-new-filter-res parse-hex-result
::
++ parse-eth-block-number parse-hex-result
::
++ parse-transaction-hash parse-hex-result
::
++ parse-eth-get-transaction-count parse-hex-result
::
++ parse-eth-get-balance parse-hex-result
::
++ parse-event-logs
(ar:dejs:format parse-event-log)
::
++ parse-event-log
=, dejs:format
|= log=json
^- event-log
=- ((ot -) log)
:~ =- ['logIndex'^(cu - (mu so))]
|= li=(unit @t)
?~ li ~
=- ``((ou -) log) ::TODO not sure if elegant or hacky.
:~ 'logIndex'^(un (cu hex-to-num so))
'transactionIndex'^(un (cu hex-to-num so))
'transactionHash'^(un (cu hex-to-num so))
'blockNumber'^(un (cu hex-to-num so))
'blockHash'^(un (cu hex-to-num so))
'removed'^(uf | bo)
==
::
address+(cu hex-to-num so)
data+so
::
=- topics+(cu - (ar so))
|= r=(list @t)
^- (lest @ux)
?> ?=([@t *] r)
:- (hex-to-num i.r)
(turn t.r hex-to-num)
==
::
++ parse-transaction-result
=, dejs:format
|= jon=json
~| jon=jon
^- transaction-result
=- ((ot -) jon)
:~ 'blockHash'^_~ :: TODO: fails if maybe-num?
'blockNumber'^maybe-num
'transactionIndex'^maybe-num
from+(cu hex-to-num so)
to+maybe-num
input+so
==
::
++ maybe-num
=, dejs:format
=- (cu - (mu so))
|= r=(unit @t)
?~ r ~
`(hex-to-num u.r)
--
::
:: utilities
::TODO give them better homes!
::
++ num-to-hex
|= n=@
^- tape
%- prefix-hex
?: =(0 n)
"0"
%- render-hex-bytes
(as-octs:mimes:html n)
::
++ address-to-hex
|= a=address
^- tape
%- prefix-hex
(render-hex-bytes 20 `@`a)
::
++ address-to-checksum
|= a=address
^- tape
=/ hexed (render-hex-bytes 20 `@`a)
=/ hash (keccak-256:keccak:crypto (as-octs:mimes:html (crip hexed)))
=| ret=tape
=/ pos 63
|-
?~ hexed (prefix-hex (flop ret))
=/ char i.hexed
?: (lth char 58) $(pos (dec pos), ret [char ret], hexed t.hexed)
=/ nib (cut 2 [pos 1] hash)
?: (lth 7 nib) $(pos (dec pos), ret [(sub char 32) ret], hexed t.hexed)
$(pos (dec pos), ret [char ret], hexed t.hexed)
::
++ transaction-to-hex
|= h=@
^- tape
%- prefix-hex
(render-hex-bytes 32 h)
::
++ prefix-hex
|= a=tape
^- tape
['0' 'x' a]
::
++ render-hex-bytes
:: atom to string of hex bytes without 0x prefix and dots.
|= a=octs
^- tape
((x-co:co (mul 2 p.a)) q.a)
::
++ pad-to-multiple
|= [wat=tape mof=@ud wer=?(%left %right)]
^- tape
=+ len=(lent wat)
?: =(0 len) (reap mof '0')
=+ mad=(mod len mof)
?: =(0 mad) wat
=+ tad=(reap (sub mof mad) '0')
%- weld
?:(?=(%left wer) [tad wat] [wat tad])
::
++ hex-to-num
|= a=@t
~| %non-hex-cord
?> =((end [3 2] a) '0x')
=< ?<(=(0 p) q) %- need
(de:base16:mimes:html (rsh [3 2] a))
--