Module path_cache 

Process-wide cache of BC5D tables loaded from explicit filesystem paths.

The bridge/solve-json surfaces accept a caller-supplied table PATH (mobile apps download the .bin themselves and hand the engine a file path), and PARSING a several-MB table on every card or solve call would dominate the request. What the cache saves is the parse; the read and CRC are the price of knowing what is actually on disk.

Entries are keyed by (canonical path, file size, CRC32 of the file's bytes) — i.e. by CONTENT. An earlier version keyed on (canonical path, file size, mtime) and could serve a stale parsed table when a file was replaced in place by same-size content within one filesystem mtime tick: the key was unchanged, so the new bytes were never read. That is a live scenario here, not a theoretical one — a table-set refresh overwrites bc5d_<caliber>.bin in place, and a regenerated table with identical dimensions has identical size. It reached a release because mtime granularity is fine enough on macOS and Linux to hide it, and only surfaced on an OpenBSD guest whose granularity is coarse enough to collide.

Size is retained alongside the CRC purely as a second, free discriminator. The cache is bounded (oldest entry evicted at capacity).

Filesystem-only by construction, so the whole module is compiled out on wasm32 (where WASM callers pass table BYTES via loadBc5dTable instead).

Functions

load_verified

Load a BC5D table from path, verifying the header (magic, version, dimensions) and the stored CRC32 exactly as Bc5dTable::load does, with the parsed result cached process-wide.

load_verified_for_caliber

load_verified plus the caliber-identity guard: the loaded table must be for the caliber of the shot that is about to use it, per Bc5dTable::ensure_caliber_matches (shot_caliber_in in INCHES).