Improve Readability Style

Adopt a “review-first” style for complex C code: keep control flow and conditions small, make side effects explicit, and avoid duplication.

Key rules: 1) Split overly long conditionals

• Avoid putting multiple parsing/validation calls into a single large if.
• Prefer sequential guarded if blocks.

2) Use guard clauses and shared cleanup

• Reduce indentation by returning early on validation failures.
• When there are multiple paths (e.g., fast-path vs fallback), share cleanup via a single label or helper, so the structure stays flat.

3) Prefer explicit branching for special modes

• Don’t hide unusual behavior inside another branch (e.g., special aggregate handling mixed into SUM). Use else if with a clear name/comment.

4) Extract duplicated “finalization”/side-effect logic

• If multiple commands repeat the same update/notification/keyspace-finalization logic, move it to a helper to keep behavior consistent (and reduce the chance of diverging implementations).

5) Enforce consistent formatting

• Always use braces for multi-line if/for/while bodies.
• For multi-line conditions, wrap the controlled block with {} for scan-ability.

6) Use named constants instead of magic numbers

• Prefer existing shared constants (e.g., buffer sizing macros) over local ad-hoc values.

Example (splitting long validation):

// Before (hard to read)
if (parseA()!=C_OK || parseB()!=C_OK || parseC()!=C_OK) return;

// After (reviewable)
if (parseA() != C_OK) return;
if (parseB() != C_OK) return;
if (parseC() != C_OK) return;

Example (shared cleanup to reduce indentation):

if (fast_path_ok) {
    goto done;
}
// fallback path

done:
cleanup_common();
return;

Applying these consistently makes diffs easier to scan, reduces reviewer cognitive load, and prevents subtle behavioral drift across similar command implementations.