{
  "title": "Split linux_configuration/C/atop_agg/atop_agg.c under the 250-line cap",
  "objective": "Bring atop_agg.c (478 lines) under the repo-wide 250-line file cap by splitting the single translation unit three ways along its existing concerns -- ingest, per-PID table management, and report emission -- with the TSV output the Python usage report consumes proven unchanged by the project's own C test binary at its existing 92.9% line / 100% function coverage.",
  "acceptance_criteria": [
    "atop_agg.c and all new .c/.h files are each at most 250 lines, and check_file_length.sh --all no longer lists any atop_agg file.",
    "make clean && make test compiles every unit under -Wall -Wextra with no new warnings and prints 'atop_agg tests: OK'. The compile line must name the new .c files, proving they are built rather than silently omitted.",
    "make coverage reports the same 92.9% lines (196 of 211) and 100% functions (13 of 13) as the pre-split baseline, measured after lcov strips test_atop_agg.c. Unchanged totals on unchanged source lines is what shows no code left test reach.",
    "The Makefile's SRC and HDR variables list every new file, and the test target compiles $(SRC) rather than a hardcoded atop_agg.c. Without this the build would link the old self-contained unit and the suite would pass with the new files unused -- a fail-open the tests cannot detect.",
    "The production binary (make, which builds at -O2 without -DATOP_AGG_NO_MAIN) links and emits a well-formed record, exercising the main path the test binary compiles out.",
    "Zero suppressions: no #pragma to silence a warning, no -Wno- flag added, and no change to the coverage or test targets' strictness."
  ],
  "out_of_scope": [
    "Any change to the output format -- the W/C/R TSV record shapes are a contract with the Python driver in system-maintenance/bin and must be byte-identical.",
    "Any change to the hash geometry (HASH_CAP_BITS, MAX_EPOCHS, MAX_TOKENS) or the aggregation arithmetic, both of which the tests pin only loosely.",
    "Widening the public interface in atop_agg.h; declarations that must cross the new unit boundary go in a private internal header instead.",
    "Wiring atop_agg into CI, which has no workflow today -- a separate piece of work."
  ],
  "verifier": "cd linux_configuration/C/atop_agg && make clean && make test (expect 'atop_agg tests: OK' and a compile line naming every unit); make coverage (expect 92.9% lines, 100% functions after the lcov strip pass); make clean && make && printf 'PRC\\tfoo\\t1\\t100\\ny\\n' | ./atop_agg (expect a well-formed W record, exit 0); bash ~/utils/scripts/check_file_length.sh --all (expect no atop_agg entry); git diff on atop_agg.h (expect empty). Captured at HEAD as the baseline and re-run after the split."
}