Beagle SCM

CODE-017: API-underuse + small-reimplementation cleanup (2026-06-11 research sweep)

A research-only per-dir sweep (11 agents, each reading ABC.md + the INDEX/headers first) found 17 spots that reimplement or under-use existing abc/dog APIs — 0 high value, 9 medium, 8 low. No bugs; the value is ABC-style consistency (typed slices over memcmp/ptr-arith, wrapped FILE.h over raw POSIX, one helper over a duplicate). The big reimplementations already landed (sha1↔hex, dog hex/dir/enc, commit parsing), so this is the incremental tail. CODE-017 does the SOLID parent-project findings behavior-preserving in ONE worktree; the abc/ findings (URI.c, TLV.c) are DEFERRED to a separate gated abc review (core, just-touched by URI-003). Conservative: skip any marginal one-off that would only churn. See CLAUDE, Issues.

Issues

Small reimplementations + pervasive API-underuse the sweep verified.

• reimplements-library: subs_eq (dog/git/SUBS.c:18) re-rolls u8csEq (4 uses); keep_push_write_all (keeper/KEEP.c:2712) re-rolls FILEFeedAll (same file uses it at 2179/2236; callers 2862/2950); a single-use subs_eq in sniff/SUBS.c.
• duplication: *_pack_uri_diff_sha defined identically in graf/MAP.c:61 and graf/LOG.c:201 (~6 lines; BLAME.c's hashlet variant is NOT a candidate).
• underuses-api (medium): memcmp→u8csEq in sniff/GET.c:277,309,1208; raw write()→FILEFeed EINTR loop in spot/LESS.c:84; manual last-dot loop→u8csRevFind in woof/CONN.c:221; manual fopen/fread/malloc→FILEMapRO in js (ABC.md §113-117 discouraged pattern).
• underuses-api (low / do only if clean): ptr-arith slice construction → a_head/a_rest (beagle ×3, js); memcpy buffer-struct assign → direct assign (bro ×4); memcmp→$eq scheme check (woof); raw POSIX PID-file I/O (sniff/WATCH.c); raw malloc UTF-8 buf → u8bIdle/u8bFeed (js/utf8.cpp:20).
• DEFERRED (abc, core — separate gated review): URI.c memcmp/memcpy→u8csEq/$eq/u8sCopy (×5); TLV.c:23 ptr-arith→$at; memset→zero() (mostly justified for complex struct init — likely WONTFIX).

Blockers

abc is core — the URI.c/TLV.c findings are NOT in this worker's scope; surface them separately for review (or WONTFIX the justified memset ones). Everything else is parent-project, one beagle commit. Value is low-to-medium across the board — keep the change behavior-preserving and resist adding churn.

Planned

One worker, parent-project only, behavior-preserving; skip-and-note anything marginal.

• Repro-first (CLAUDE §17): these are mechanical, but keep the full suite green; add a case only where behavior could shift.
• reimplements/dup: subs_eq→u8csEq; keep_push_write_all→FILEFeedAll; one shared GRAFPackUriDiffSha for MAP.c/LOG.c.
• underuse mediums: memcmp→u8csEq (sniff), write()→FILEFeed (spot), u8csRevFind (woof), FILEMapRO (js).
• underuse lows: do ONLY where the swap is clean and safe (ptr-arith→slice macros, memcpy→assign, raw-POSIX→wrapper); skip and list any that would just churn.
• Build + ctest; STOP at the gate. Report done vs skipped with reasons. abc/ untouched.