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Test, Build, and Deploy / test-build-deploy (push) Failing after 3m2s
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
67 lines
2.2 KiB
OCaml
67 lines
2.2 KiB
OCaml
(** CIDv1 computation — pure OCaml, WASM-safe.
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Multihash + CIDv1 + multibase base32-lower (RFC 4648, no pad,
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multibase prefix 'b'). Codecs: dag-cbor 0x71, raw 0x55. Hash
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codes: sha2-256 0x12, sha3-256 0x16. Reference: the multiformats
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specs (unsigned-varint, multihash, cid, multibase). No deps. *)
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open Sx_types
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(* Unsigned LEB128 (multiformats unsigned-varint). *)
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let varint (n : int) : string =
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let buf = Buffer.create 4 in
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let n = ref n in
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let cont = ref true in
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while !cont do
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let b = !n land 0x7f in
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n := !n lsr 7;
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if !n = 0 then (Buffer.add_char buf (Char.chr b); cont := false)
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else Buffer.add_char buf (Char.chr (b lor 0x80))
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done;
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Buffer.contents buf
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(* RFC 4648 base32 lowercase, no padding. *)
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let b32_alpha = "abcdefghijklmnopqrstuvwxyz234567"
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let base32_lower (s : string) : string =
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let buf = Buffer.create ((String.length s * 8 + 4) / 5) in
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let acc = ref 0 and bits = ref 0 in
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String.iter (fun c ->
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acc := (!acc lsl 8) lor (Char.code c);
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bits := !bits + 8;
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while !bits >= 5 do
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bits := !bits - 5;
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Buffer.add_char buf b32_alpha.[(!acc lsr !bits) land 0x1f]
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done) s;
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if !bits > 0 then
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Buffer.add_char buf b32_alpha.[(!acc lsl (5 - !bits)) land 0x1f];
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Buffer.contents buf
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(* "abef" -> the 2 raw bytes. *)
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let unhex (h : string) : string =
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let n = String.length h / 2 in
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let b = Bytes.create n in
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for i = 0 to n - 1 do
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Bytes.set b i
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(Char.chr (int_of_string ("0x" ^ String.sub h (2 * i) 2)))
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done;
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Bytes.unsafe_to_string b
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(* multihash = varint(code) || varint(len) || digest *)
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let multihash (code : int) (digest : string) : string =
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varint code ^ varint (String.length digest) ^ digest
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(* CIDv1 = 0x01 || varint(codec) || multihash ; multibase 'b' base32. *)
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let cidv1 (codec : int) (mh : string) : string =
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"b" ^ base32_lower ("\x01" ^ varint codec ^ mh)
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let codec_dag_cbor = 0x71
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let mh_sha2_256 = 0x12
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(* Canonicalize an SX value: dag-cbor encode -> sha2-256 ->
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multihash -> CIDv1 (dag-cbor codec). *)
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let cid_from_sx (v : value) : string =
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let cbor = Sx_cbor.encode v in
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let digest = unhex (Sx_sha2.sha256_hex cbor) in
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cidv1 codec_dag_cbor (multihash mh_sha2_256 digest)
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