Function cbm_index_mark

internal/cbm/cbm.c:684–694

Test-only deterministic fault injection for the crash/hang supervisor tests. * Gated entirely behind env vars that are never set in production; a matching * rel_path either aborts (a fault signal the supervisor classifies as a crash) * or spins forever (an external-scanner infinite loop the quiet-timeout kills). * This gives an honest guard — green iff the supervisor actually contains a real

 * unlucky in-flight file is never quarantined alone. The env var is set
 * solely by the supervisor during recovery — a no-op on normal runs. */
static void cbm_index_mark(const char *rel_path, char event) {
    const char *mf = getenv("CBM_INDEX_MARKER_FILE");
    if (!mf || !mf[0] || !rel_path || !rel_path[0]) {
        return;
    }
    FILE *f = cbm_fopen(mf, "ab");
    if (f) {
        (void)fprintf(f, "%c %s\n", event, rel_path);
        (void)fclose(f);
    }
}

void cbm_index_mark_start(const char *rel_path) {
    cbm_index_mark(rel_path, 'S');