Persistent store with Git semantics: lazy reads, delayed writes, content-addressing
Wire RS into tm-sync, implement convolutional codec, add interop vectors
- tm-sync Reed_solomon: now uses ocaml-reed-solomon with CCSDS
interleaving (I=1..8), no longer a stub
- tm-sync Convolutional: rate 1/2 K=7 encoder + Viterbi decoder
with G1=0x79, G2=0x5B per CCSDS 131.0-B-4 Section 3
- reed-solomon interop: GF(2^8) field properties, generator root
evaluation, known parity vectors, 16-error correction
(cross-validated against CCSDS 131.0-B-4 Annex F)
- tm-sync interop: full 255-byte PN sequence from bg2bhc/gr-lilacsat,
convolutional impulse response matching generator polynomials
+51
-11
+15
-11
lib/pds_interop.ml
+15
-11
lib/pds_interop.ml
···
4
4
(Merkle Search Tree) and blockstore, enabling interoperability between the
5
5
PDS record API and the MST key-value layer. *)
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6
7
+
(* ATProto repos have a single head — no branches. Only "refs/heads/main"
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+
(and "HEAD") are accepted; all other ref names raise Invalid_argument. *)
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+
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+
let is_head_ref name = name = "HEAD" || name = "refs/heads/main"
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+
7
12
module Pds_backend : Backend.S with type t = Pds.t and type hash = Atp.Cid.t =
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struct
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type t = Pds.t
···
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let read pds cid = (Pds.blockstore pds)#get cid
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let write pds cid data = (Pds.blockstore pds)#put cid data
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let exists pds cid = (Pds.blockstore pds)#has cid
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-
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-
let get_ref pds name =
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-
if name = "HEAD" || name = "refs/heads/main" then Pds.head pds else None
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+
let get_ref pds name = if is_head_ref name then Pds.head pds else None
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21
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let set_ref pds name cid =
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-
if name = "HEAD" || name = "refs/heads/main" then Pds.set_head pds cid
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+
if is_head_ref name then Pds.set_head pds cid
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+
else
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+
invalid_arg
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+
(Fmt.str "ATProto PDS does not support branches (got %S)" name)
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let test_and_set_ref pds name ~test ~set =
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-
let current =
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-
if name = "HEAD" || name = "refs/heads/main" then Pds.head pds else None
25
-
in
29
+
if not (is_head_ref name) then
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+
invalid_arg
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+
(Fmt.str "ATProto PDS does not support branches (got %S)" name);
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+
let current = Pds.head pds in
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33
let matches =
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match (test, current) with
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35
| None, None -> true
···
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37
| _ -> false
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38
in
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if matches then (
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-
(match set with
34
-
| None -> ()
35
-
| Some cid ->
36
-
if name = "HEAD" || name = "refs/heads/main" then Pds.set_head pds cid);
40
+
(match set with None -> () | Some cid -> Pds.set_head pds cid);
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41
true)
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42
else false
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43
+36
test/test_pds_interop.ml
+36
test/test_pds_interop.ml
···
415
415
(text = Some (`String "Hello world"))
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| _ -> Alcotest.fail "expected Map")
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+
(* ---- Irmin store API on PDS ---- *)
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+
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+
let test_pds_store_main_branch () =
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+
with_temp_dir @@ fun path ->
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+
Eio.Switch.run @@ fun sw ->
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+
let pds = Pds.v ~sw path ~did:test_did in
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+
let store = Irmin.Mst.of_pds pds in
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+
let tree = Irmin.Tree.add Irmin.Tree.empty [ "key" ] "value" in
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+
let h = Irmin.commit store ~tree ~parents:[] ~message:"init" ~author:"test" in
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+
Irmin.set_head store ~branch:"main" h;
428
+
Alcotest.(check (list string)) "only main" [ "main" ] (Irmin.branches store);
429
+
match Irmin.head store ~branch:"main" with
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+
| Some h' -> Alcotest.(check bool) "head set" true (Irmin.Hash.equal h h')
431
+
| None -> Alcotest.fail "head should exist"
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+
433
+
let test_pds_store_no_other_branches () =
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+
with_temp_dir @@ fun path ->
435
+
Eio.Switch.run @@ fun sw ->
436
+
let pds = Pds.v ~sw path ~did:test_did in
437
+
let store = Irmin.Mst.of_pds pds in
438
+
let tree = Irmin.Tree.add Irmin.Tree.empty [ "a" ] "1" in
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+
let h = Irmin.commit store ~tree ~parents:[] ~message:"init" ~author:"test" in
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+
Irmin.set_head store ~branch:"main" h;
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+
(* Setting a non-main branch should raise *)
442
+
let raised =
443
+
try
444
+
Irmin.set_head store ~branch:"dev" h;
445
+
false
446
+
with Invalid_argument _ -> true
447
+
in
448
+
Alcotest.(check bool) "set_head on dev raises" true raised;
449
+
(* head on non-main returns None *)
450
+
Alcotest.(check bool)
451
+
"no dev branch" true
452
+
(Irmin.head store ~branch:"dev" = None)
453
+
418
454
let suite =
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455
( "pds_interop",
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456
[