## Summary
Players could not place **any door** while customizing a house, and placing other pieces could disconnect them outright. Staff saw neither problem: `HouseFoundation.Designer_Build` only enforces `ValidPiece` below `GameMaster`.
Original report and diagnosis by @SynPDX.
## Root cause 1 — no door is ever registered
The retail client's `doors.txt` separates its header rows with lines of **bare tabs** (it is the only sheet that does):
```
int<TAB>int<TAB>...<TAB>string
<TAB><TAB><TAB><TAB><TAB><TAB><TAB><TAB><TAB><TAB> <-- 10 tabs, not an empty line
Category<TAB>Piece1<TAB>...<TAB>FeatureMask<TAB>Comment
<TAB><TAB><TAB><TAB><TAB><TAB><TAB><TAB><TAB><TAB>
0<TAB>1657<TAB>1659<TAB>...
```
`Spreadsheet.ReadLine` skipped a line only when `line.Length > 0`. A 10-tab line has length 10, so it was returned as the **names row** — every column ended up named `""`, `GetColumnID("Piece1")` and friends returned `-1`, and not one of the 230 door graphics was registered. Unregistered item IDs keep the `-1` sentinel, and `CheckValidity` rejects those, so `ValidPiece` refused every door.
ClassicUO skips these lines (`string.IsNullOrWhiteSpace` in `HouseCustomizationManager.ParseFile`), which is why the client happily offers doors the server then rejects.
Measured against a retail 7.0.x `doors.txt` using the shipped `Spreadsheet`:
| | `FeatureMask` column | door graphics registered |
|---|---|---|
| before | `-1` | **0** |
| after | `9` | **230** |
## Root cause 2 — `IndexOutOfRangeException` out of the packet handler
Every sheet ends in a cosmetic `Comment` column that ModernUO never reads, and client sheets write an empty comment as a plain newline with no trailing tab. `Split('\t')` then returns one field fewer than the header declares, and the parser indexed past the end:
```
System.IndexOutOfRangeException: Index was outside the bounds of the array.
at Server.Multis.Spreadsheet..ctor(String path)
at Server.Multis.ComponentVerification.LoadSpreadsheet(...)
at Server.Multis.ComponentVerification.IsItemValid(Int32 itemID)
at Server.Multis.HouseFoundation.ValidPiece(Int32 itemID, Boolean roof)
at Server.Multis.HouseFoundation.Designer_Build(NetState state, ...)
```
The client's own parser only requires the columns up to `FeatureMask` — ClassicUO's `CustomHouseMisc.Parse` guards on `scanf.Length >= 12` for a 13-column `misc.txt` — so such a row is valid data listing real pieces. Missing trailing fields are now treated as empty rather than dropping the row, which would unregister every piece the row lists and reproduce the door symptom.
`EnsureLoaded` also set `_loaded` before loading, so once the throw escaped, an all `-1` table stayed cached and rejected everything for players from then on — the same player-visible symptom as #2500.
## Also made explicit rather than accidental
- **Named the table sentinels.** `NotAComponent` (-1) is the anti-cheat guard and the initial state; `NoFeatureRequired` (0) is a piece with no expansion gate — how `walls.txt` encodes pre-AOS base pieces and what `housing.bin` collapses to under `HousingTierMask` (#2500).
- **A sheet with no `FeatureMask` column is refused and logged.** `GetInt32` on a missing column returns 0 = `NoFeatureRequired`, which would have silently marked every piece in that sheet unconditionally placeable regardless of expansion. This was previously only harmless by accident.
- **A sheet matching none of its expected tile columns is refused and logged** — that is what `doors.txt` was doing silently. Individual missing columns stay tolerated, since older sheets predate columns such as `walls.txt`'s `SecondAltWindowS`/`E`.
- **Catch per sheet**, so one unreadable file no longer costs the other six.
- **Header guards**: an empty file or a types-only file raised a `NullReferenceException`; a names row shorter than the types row indexed past the end.
- **Fall back to the component sheets when `housing.bin` cannot be read**, instead of passing `null` into a `SpanReader`.
`_loaded` is still set before loading, deliberately: this runs from the design packet handler, and retrying would re-read every sheet on each subsequent placement attempt.
Sheet precedence is **unchanged** — the client's copies stay authoritative and `Data/Components` remains the fallback.
## Verification
- Retail 7.0.x client `doors.txt` through the shipped `Spreadsheet`: 0 door graphics before, 230 after.
- 5 new tests in `SpreadsheetTests` covering the tab separators, the omitted trailing field, per-row recovery, and both header guards. All 5 fail against `main` and pass here.
- `dotnet build` clean (0 warnings, 0 errors); `UOContent.Tests` 642/642.
> [!IMPORTANT]
> **Breaking Changes**
> - DecodePacket and EncodePacket delegates replaced with IClientEncryption interface
> - NetState.Connection (Socket) replaced with internal RingSocket management
> - NetState.RecvPipe and NetState.SendPipe removed (buffers managed internally)
## Summary
Upgrades the networking stack from PollGroup-based I/O to io_uring, significantly improving I/O performance on Linux.
This also adds native client encryption support for encrypted UO clients.
## Major Changes
io_uring Networking Architecture
- Replaced PollGroup with IORingGroup for async socket I/O operations
- Removed Pipe.cs (mirrored ring buffer) and TcpServer.cs in favor of RingSocketManager
- Added NetState.Network.cs - centralized network infrastructure handling accept, recv, send, and disconnect
completions
- Added SocketHelper.cs - platform-specific socket utilities for raw socket handle operations (getpeername,
getsockname)
- Buffer management now handled by RingSocketManager with configurable slab allocation
### Client Encryption Support
- Added full encryption stack in Network/Encryption/:
- EncryptionConfig.cs - configurable encryption modes (None, Unencrypted, Encrypted, Both)
- EncryptionManager.cs - encryption detection and initialization for login/game packets
- LoginEncryption.cs - handles login packet encryption with version-derived keys
- GameEncryption.cs - handles game server encryption using Twofish
- TwofishEngine.cs - optimized Twofish block cipher implementation
- LoginKeys.cs - encryption key table for client versions
- IClientEncryption.cs - interface for client encryption implementations
### NetState Improvements
- Replaced Socket Connection with RingSocket _socket for managed socket lifecycle
- Changed from GCHandle polling to event-based completion processing
- Disconnect handling now properly waits for pending sends to flush
- Simplified connecting socket management using lazy queue removal
### Configuration
- New settings: network.encryptionMode and network.encryptionDebug
- Encryption mode flags: Unencrypted, Encrypted, or Both
### Dependencies
- Replaced PollGroup NuGet package with IORingGroup
- Linux requires liburing-dev / liburing-devel package
### Test plan
- Verify server starts and accepts connections on Linux with io_uring
- Verify server starts and accepts connections on Windows (fallback to IOCP)
- Test unencrypted client connections (ClassicUO with encryption disabled)
- Test encrypted client connections if available
- Verify graceful disconnect flushes pending data
- Confirm CI builds pass on all target platforms
### Summary
- Generalizes the On/Off toggle items concept
- Updates the OnOffGump so it is static
- Standardizes OnOff items so they can be used by staff
### Notes
Decided to not fix#1417 because it is not clear that the clilocs or errors are for that purpose. Can't test this on OSI anyways.
> [!Note]
> **Developer Note**
> Now developers will only need to build/run the Application project instead of everything.
> When adding new projects, make sure to:
> 1. Add a reference to that project in the Application project.
> 2. Add the dll file to the Distribution/Data/assemblies.json file
### Summary
- Adds an application project
- Consolidates process restarts to use `Core.Kill(true)`
- Removes some old messaging, for example processor optimization
- Fixes missing build cleanup
> [!Warning]
> Users on Linux/OSX will need to follow the Readme
> and make sure `libdeflate` is properly installed
> [!Note]
> **Developer Note**
> The API for compression has changed. Use `Deflate.Standard` for the same functionality.
### Summary
* Replaces Zlib with LibDeflate for a 50% performance improvement!
* Adds MacOS 14 to properly test Arm64
## BREAKING CHANGE
- Deletes `map.GetObjectsInRange` and `map.GetObejctsInBounds`
### Notes
Developers are expected to enumerate mobiles and items separately now using `map.GetMobilesInRange` and `map.GetItemsInRange`. This helps keep the code streamlined so we don't have to maintain multiple copies of ref struct enumerators that do the same thing.
### Fixes
- [X] Fixes bug with planks closing
- [X] Fixes issue with iterating items/mobiles from a null map
### Summary
Eliminates `IPooledEnumerable<T>` and `eable.Free()` from `Map` for items. This drastically simplifies code that iterates in range, for example:
```cs
foreach (var item in m.GetItemsInRange(5))
{
}
```
The code above no longer requires an eable and calling `Free()`.
## Breaking Changes
Incoming packet registration signature has changed to:
```cs
delegate* void OnReceiveCallback(NetState state, SpanReader reader, int packetLength);
IncomingPackets.Register(int packetID, int length, bool ingame, OnReceiveCallback onReceive);
```
For example, an incoming packet handler signature would now look like this:
```cs
public static void SomeIncomingPacket(NetState state, SpanReader reader, int packetLength)
{
// Parse the data
}
```
## Summary
Updates the network Pipe class to use a mirrored memory technique. This technique involves mapping the same physical memory to two contiguous virtual memory spaces so the byte buffer appears duplicated. This allows writing to a double-sized array to wrap around without the need for the `CircularBuffer` classes.
In practice this allows us to use `Span<byte>` as if the buffer was a regular array.
### Bug Fixes
- [X] Fixes bad fixed length string parsing
- [X] Adds `ToSpan()` for SpanWriter.
- [X] Moves house files to UOContent/Multis/Houses
- [X] Adds house packets
### SpanWriter.ToSpan()
`ToSpan()` returns an `SpanOwner` struct which allows access to the buffer as a Span by calling `Span`.
Example:
```cs
public SpanOwner CreatePacket()
{
var writer = new SpanWriter(0x400);
// write some stuff
return writer.ToSpan();
}
```
In this example, we are creating a packet and returning the `SpanOwner` for caching. This means in the future we can do something like this:
```cs
ns.Send(_cachedPacket.Span);
```
Where `_cachedPacket` is the `SpanOwner`
Notes:
Do not use a SpanWriter, or attempt to dispose of it after calling `ToSpan()`. Doing so will probably cause an NPE.
- [X] Converts boat packets
- [X] Makes a packet container builder for packet 0xF7
- [X] Generalizes world item packet so it works for mobiles too
Notes:
- This PR doesn't address proper smooth movement for boats.
