# Batch Report

**Batch**: 4
**Tasks**: 06_refactor_crypto_uploads, 07_refactor_thread_safety
**Date**: 2026-04-13

## Task Results

| Task | Status | Files Modified | Tests | AC Coverage | Issues |
|------|--------|---------------|-------|-------------|--------|
| 06_refactor_crypto_uploads | Done | 3 files | 18/18 pass | 4/4 ACs covered | None |
| 07_refactor_thread_safety | Done | 1 file | 18/18 pass | 3/3 ACs covered | None |

## AC Test Coverage: All covered
## Code Review Verdict: PASS (manual review)
## Auto-Fix Attempts: 0
## Stuck Agents: None

## Changes Summary

### Task 06 (security.pyx, binary_split.py, api_client.pyx)
- C03: Replaced manual PKCS7 unpadding with `padding.PKCS7(128).unpadder()` in `security.pyx`
- C04: Integrated streaming PKCS7 unpadder into `decrypt_archive` pipeline in `binary_split.py`, removed post-hoc file truncation
- C09: Added CDN upload return value check in `upload_big_small_resource`
- C10: Removed exception swallowing in `upload_file` — errors now propagate

### Task 07 (main.py)
- C01: Double-checked locking for `get_api_client()` singleton
- C02: Encapsulated unlock state in `_UnlockStateHolder` class with lock-guarded access
- C06: Replaced silent `except OSError: pass` with `logger.warning`

## Next Batch: 08_refactor_cleanup