Strengthen savedata persistence against corruption and race conditions:
- SHA-256 checksum: hash the decompressed blob on every save, store in
new savedata_hash column, verify on load to detect silent corruption.
Pre-existing characters with no hash are silently upgraded on next save.
- Atomic transactions: wrap character data + house data + hash + backup
into a single DB transaction via SaveCharacterDataAtomic, so a crash
mid-save never leaves partial state.
- Per-character save mutex: CharacterLocks (sync.Map of charID → Mutex)
serializes concurrent saves for the same character, preventing races
that could defeat corruption detection. Different characters remain
fully independent.
Migration 0008 adds the savedata_hash column to the characters table.
Prevent savedata corruption and denial-of-service by adding four layers
of protection to the save pipeline:
- Bounded decompression (nullcomp.DecompressWithLimit): caps output size
to prevent OOM from crafted payloads that expand to exhaust memory
- Bounds-checked delta patching (deltacomp.ApplyDataDiffWithLimit):
validates offsets before writing, returns errors for negative offsets,
truncated patches, and oversized output; ApplyDataDiff now returns
original data on error instead of partial corruption
- Size limits on save handlers: rejects compressed payloads >512KB and
decompressed data >1MB before processing; applied to main savedata,
platedata, and platebox diff paths
- Rotating savedata backups: 3 slots per character with 30-minute
interval, snapshots the previous state before overwriting, backed by
new savedata_backups table (migration 0007)
Move ~300 test functions from 21 catch-all files (handlers_core_test.go,
handlers_coverage*_test.go, *_coverage_test.go) into the *_test.go file
matching each handler's source file. This makes tests discoverable by
convention: tests for handlers_guild.go live in handlers_guild_test.go.
New files: handlers_guild_mission_test.go, sys_time_test.go.
No test logic changed — pure file reorganization.
The userBinary and minidata maps with their locks were spread across
Server as raw fields with manual lock management. Cross-channel session
searches also required acquiring nested locks (server lock + binary
lock). Encapsulating in dedicated types eliminates the nested locking
and reduces Server's field count by 4.
Move all direct DB calls from handlers_festa.go (23 calls across 8
tables) and handlers_tower.go (16 calls across 4 tables) into
dedicated repository structs following the established pattern.
FestaRepository (14 methods): lifecycle cleanup, event management,
team souls, trial stats/rankings, user state, voting, registration,
soul submission, prize claiming/enumeration.
TowerRepository (12 methods): personal tower data (skills, progress,
gems), guild tenrouirai progress/scores/page advancement, tower RP.
Also fix pre-existing nil pointer panics in integration tests by
adding SetTestDB helper that initializes both the DB connection and
all repositories, and wire the done channel in createTestServerWithDB
to prevent Shutdown panics.
- Guard nil listener/acceptConns in Server.Shutdown() to prevent panic
in test servers that don't bind a network listener
- Remove redundant userBinaryPartsLock in TestHandleMsgMhfLoaddata that
caused a deadlock with handleMsgMhfLoaddata's own lock acquisition
- Increase test save blob size from 200 to 150000 bytes to accommodate
ZZ save pointer offsets (up to 146728)
- Initialize MHFEquipment.Sigils[].Effects slices in test data to
prevent index-out-of-range panic in SerializeWarehouseEquipment
- Insert warehouse row before updating it (UPDATE on 0 rows is not an
error, so the INSERT fallback never triggered)
- Use COALESCE for nullable kouryou_point column in kill counter test
- Fix duplicate-add test expectation (CSV helper correctly deduplicates)
Re-enable the golangci-lint job in CI (disabled Oct 2025), update to
Go 1.25 and golangci-lint-action v7. Fix errcheck, gosimple S1009,
staticcheck SA4031 and SA2001 errors across 54 files. Remaining ~39
lint errors will be addressed in follow-up commits.