fed-sx-m1: Step 4c — bootstrap:read_genesis/0,1 + 5 helpers + 15 read tests

next/kernel/bootstrap.erl

@@ -0,0 +1,96 @@
+-module(bootstrap).
+-export([read_genesis/0, read_genesis/1,
+         read_section/2, sections/0, section_subdir/1,
+         default_base/0, ends_with_sx/1]).
+
+%% Genesis bundle reader per design §12.2.
+%%
+%% read_genesis/0,1 walks the seven canonical section subdirectories
+%% under `next/genesis/`, filters .sx files, reads each file into a
+%% binary, and returns a structured snapshot:
+%%
+%%   {ok, [{Section :: atom,
+%%          [{FileName :: binary, FileBytes :: binary}, ...]},
+%%         ...]}
+%%
+%% Step 4d will compute the bundle CID by hashing the assembled
+%% byte string across all entries; Step 4e will register the parsed
+%% definitions in the kernel registry.
+%%
+%% Port note: this module does NOT parse the .sx contents. The
+%% Erlang-on-SX port has no in-Erlang path from binary bytes to SX
+%% structured terms (same substrate gap that parked Step 3b); the
+%% bundle CID needs only the raw bytes, and registry registration
+%% will happen via an SX-side helper that the kernel hands the
+%% binary contents to. read_genesis/1 ignores its arg in v1 except
+%% to swap the BasePath — `default_base/0` is "next/genesis".
+%%
+%% Port note 2: string-literal binary segments `<<"abc">>` truncate
+%% to one byte in this port, so all path constants are hand-spelled
+%% as integer-segment binaries.
+
+%% ── Public API ──────────────────────────────────────────────────
+
+%% "next/genesis"
+default_base() ->
+    <<110,101,120,116,47,103,101,110,101,115,105,115>>.
+
+read_genesis() ->
+    read_genesis(default_base()).
+
+read_genesis(BasePath) ->
+    {ok, lists:map(
+           fun (S) -> {S, read_section(BasePath, S)} end,
+           sections())}.
+
+sections() ->
+    [activity_types, object_types, projections,
+     validators, codecs, sig_suites, audience].
+
+%% "activity-types"
+section_subdir(activity_types) ->
+    <<97,99,116,105,118,105,116,121,45,116,121,112,101,115>>;
+%% "object-types"
+section_subdir(object_types) ->
+    <<111,98,106,101,99,116,45,116,121,112,101,115>>;
+%% "projections"
+section_subdir(projections) ->
+    <<112,114,111,106,101,99,116,105,111,110,115>>;
+%% "validators"
+section_subdir(validators) ->
+    <<118,97,108,105,100,97,116,111,114,115>>;
+%% "codecs"
+section_subdir(codecs) ->
+    <<99,111,100,101,99,115>>;
+%% "sig-suites"
+section_subdir(sig_suites) ->
+    <<115,105,103,45,115,117,105,116,101,115>>;
+%% "audience"
+section_subdir(audience) ->
+    <<97,117,100,105,101,110,99,101>>.
+
+read_section(BasePath, Section) ->
+    SubDir = section_subdir(Section),
+    %% 47 = '/'
+    Path = <<BasePath/binary, 47, SubDir/binary>>,
+    case file:list_dir(Path) of
+        {ok, Names} ->
+            SxNames = lists:filter(fun (N) -> ends_with_sx(N) end, Names),
+            lists:map(fun (Name) -> read_one(Path, Name) end, SxNames);
+        {error, _} ->
+            []
+    end.
+
+%% Suffix check on the .sx extension. 46='.' 115='s' 120='x'.
+ends_with_sx(<<46, 115, 120>>) -> true;
+ends_with_sx(<<>>) -> false;
+ends_with_sx(<<_, Rest/binary>>) -> ends_with_sx(Rest).
+
+%% ── Internal ────────────────────────────────────────────────────
+
+read_one(DirPath, Name) ->
+    Full = <<DirPath/binary, 47, Name/binary>>,
+    case file:read_file(Full) of
+        {ok, Bytes} -> {Name, Bytes};
+        {error, R}  -> {Name, {error, R}}
+    end.