eve.aio.windows.tcp

Async TCP listener and connection primitives for Windows.

This module provides the Windows implementation of TCP networking primitives using Winsock2 API.

var ACCEPT_ADDR_LEN ACCEPT_BUFFER_SIZE SOMAXCONN TCP_READ_BUFFER_SIZE
alias AcceptCallback CloseCallback ConnectCallback ConnectionCallback DataCallback ErrorCallback WritableCallback
struct AddrinfoRange TcpConnection TcpConnectionConfig TcpListener TcpListenerConfig
class TcpConnectionState TcpListenerState
fn addrinfoRange copyStringz mapAdoptError mapConnectError mapListenError mapWsaError portToString queryLocalPort setNonBlocking socketError validated wouldBlock

Types 14

structTcpConnectionConfig

Connection-side buffer configuration.

Fields
size_t highWaterMarkMaximum queued bytes before `send` starts reporting pressure.
size_t lowWaterMarkQueue threshold below which `onWritable` may fire again.
Methods
bool isValid() @property const pure @safe nothrow @nogcValidate the config.
structTcpListenerConfig

Listener-side socket configuration.

Fields
int backlogPending accept backlog passed to `listen`.
Methods
bool isValid() @property const pure @safe nothrow @nogcValidate the config.
private aliasConnectCallback = void delegate(ref TcpConnection connection) @safe
private aliasDataCallback = void delegate(ref TcpConnection connection, scope const(ubyte)[] data) @safe
private aliasWritableCallback = void delegate(ref TcpConnection connection) @safe
private aliasCloseCallback = void delegate(ref TcpConnection connection, SocketCloseReason reason) @safe
private aliasErrorCallback = void delegate(ref TcpConnection connection, int errorNumber) @safe
private aliasAcceptCallback = void delegate(ref TcpListener listener, Handle clientHandle) @safe
private aliasConnectionCallback = void delegate(ref TcpListener listener, ref TcpConnection connection) @safe
structTcpConnection

Async TCP connection wrapper.

Wraps a non-blocking TCP socket and integrates with the Layer 1 event loop for async read/write operations with backpressure support.

Fields
TcpConnectionState _state
Methods
TcpConnection create(TcpConnectionConfig config = TcpConnectionConfig.init) @trusted nothrowCreate a detached connection wrapper.
void onConnect(ConnectCallback callback) @property @trustedSet the connect callback.
void onData(DataCallback callback) @property @trustedSet the inbound data callback.
void onWritable(WritableCallback callback) @property @trustedSet the writable callback.
void onClose(CloseCallback callback) @property @trustedSet the close callback.
void onError(ErrorCallback callback) @property @trustedSet the error callback.
bool isOpen() @property const @safe nothrow @nogcReport whether the wrapper currently owns an open socket.
SocketState state() @property const @safe nothrow @nogcReport the current connection state.
size_t sendQueueLen() @property const @safe nothrow @nogcReport the current queued send size.
bool isWritable() @property const @safe nothrow @nogcReport whether the connection is currently writable from the caller's perspective.
IpAddress remoteAddress() @property const @safe nothrow @nogcReport the remote address of the connection.
IpAddress localAddress() @property const @safe nothrow @nogcReport the local address of the connection.
AdoptResult adopt(ref EventLoop loop, Handle clientHandle) @trusted nothrowAdopt an already-accepted client socket.
ConnectResult connect(ref EventLoop loop, scope const(char)[] host, ushort port, CancelToken cancel = CancelToken .invalid) @trusted nothrowStart a non-blocking connection attempt.
SendResult send(scope const(ubyte)[] data) @trustedSend bytes over the connection.
void pauseReading() @trusted nothrowPause socket read delivery.
void resumeReading() @trusted nothrowResume socket read delivery.
void close() @trusted nothrowClose the connection.
void dispose() @trusted nothrowDispose the connection and its watcher registration.
bool track(Coord)(ref Coord coordinator) @trusted nothrowTrack this connection for graceful shutdown.
TcpConnectionState mutableState() @trusted nothrow
structTcpListener

Async TCP listener wrapper.

Wraps a non-blocking TCP listening socket and integrates with the Layer 1 event loop for async accept operations.

Fields
TcpListenerState _state
Methods
TcpListener create(TcpListenerConfig config = TcpListenerConfig.init) @trustedCreate a detached listener wrapper.
void onAccept(AcceptCallback callback) @property @trustedSet the accept callback.
void onConnection(ConnectionCallback callback) @property @trustedSet the high-level connection callback.
bool isOpen() @property const @safe nothrow @nogcReport whether the listener currently owns an open socket.
ushort localPort() @property const @safe nothrow @nogcReport the effective local port once listening.
ListenResult listen(ref EventLoop loop, scope const(char)[] host, ushort port) @trustedStart listening on the requested endpoint.
void close() @trusted nothrowClose the listener.
void dispose() @trusted nothrowDispose the listener and its watcher registration.
bool track(Coord)(ref Coord coordinator) @trusted nothrowTrack this listener for graceful shutdown.
TcpListenerState mutableState() @trusted nothrow
private classTcpConnectionState : IShutdownTrackable
Fields
ConnectCallback onConnect
DataCallback onData
WritableCallback onWritable
CloseCallback onClose
ErrorCallback onError
EventLoop * _loop
SOCKET _socket
Token _token
TcpConnectionConfig _config
bool _readingPaused
bool _watchingWrite
bool _awaitingWritable
bool _closeDelivered
ubyte[] _sendQueue
SocketState _state
int _lastError
IpAddress _remoteAddress
IpAddress _localAddress
CancelToken _cancelToken
CancelToken _shutdownToken
bool _draining
bool _useOverlappedIoWhether this connection uses overlapped I/O mode.
Token _prepareTokenPrepare token for polling IOCP completion status.
OVERLAPPED _readOverlappedOverlapped structure for pending read operations.
OVERLAPPED _writeOverlappedOverlapped structure for pending write operations.
ubyte[TCP_READ_BUFFER_SIZE] _readBufferRead buffer — must remain valid during overlapped read.
ubyte[TCP_READ_BUFFER_SIZE] _writeBufferWrite buffer — must remain valid during overlapped write.
bool _readInProgressWhether a read operation is currently in progress.
bool _writeInProgressWhether a write operation is currently in progress.
size_t _pendingWriteLenNumber of bytes in the current pending write.
ConnectExFunc _connectExConnectEx function pointer (loaded on first use).
OVERLAPPED _connectOverlappedOverlapped structure for pending connect operation.
bool _connectInProgressWhether a connect operation is currently in progress.
ubyte[] _pausedReceiveBufferBuffer for data received while reading is paused (IOCP mode only). When paused, incoming data is stored here instead of being delivered.
Methods
void initiateShutdown(CancelToken token) @safe nothrow
void performDrain() @safe nothrow
void forceAbort() @safe nothrow
bool isClosed() @property const @safe nothrow @nogc
bool isOpen() @property const @safe nothrow @nogc
size_t sendQueueLen() @property const @safe nothrow @nogc
bool isWritable() @property const @safe nothrow @nogc
IpAddress remoteAddress() @property const @safe nothrow @nogc
IpAddress localAddress() @property const @safe nothrow @nogc
AdoptResult adopt(ref EventLoop loop, Handle clientHandle) @trusted nothrow
ConnectResult connect(ref EventLoop loop, scope const(char)[] host, ushort port, CancelToken cancel = CancelToken .invalid) @trusted nothrow
private int bindToAnyAddress(SOCKET sock, int family) @trusted nothrowBind socket to any available local address.
private int submitConnectEx(const(sockaddr) * addr, int addrlen) @trusted nothrowSubmit a ConnectEx operation.
SendResult send(scope const(ubyte)[] data) @trusted nothrowSend data on the connection.
void pauseReading() @trusted nothrow
void resumeReading() @trusted nothrow
void closeExplicitly() @trusted nothrow
void handleIo(ref EventLoop loop, Token token, IoReady ready) @safe nothrow
TcpConnection owner() @safe nothrow
void finishConnect() @trusted nothrow
void readAvailable() @trusted nothrow
void flushSendQueue() @trusted nothrow
int refreshInterest() @trusted nothrow
void fail(int errorNumber) @trusted nothrow
void closeInternal(SocketCloseReason reason, int errorNumber, bool invokeCallback) @trusted nothrow
void closeWithoutCallback() @trusted nothrow
void invokeConnect() @trusted nothrow
void invokeData(scope const(ubyte)[] data) @trusted nothrow
void invokeWritable() @trusted nothrow
void invokeError(int errorNumber) @trusted nothrow
void invokeClose(SocketCloseReason reason) @trusted nothrow
private IpAddress toIpAddress(const sockaddr * addr) @trusted nothrow @nogc
void handlePrepare(ref EventLoop loop, Token token) @trusted nothrowHandle prepare phase callback from the event loop.
void processConnectCompletion() @trusted nothrowProcess a completed ConnectEx operation.
int associateWithIocp() @trusted nothrowAssociate the socket with the event loop's IOCP.
void submitRecv() @trusted nothrowSubmit an overlapped receive operation.
void processRecvCompletion() @trusted nothrowProcess a completed receive operation.
void submitSend() @trusted nothrowSubmit an overlapped send operation.
void processSendCompletion() @trusted nothrowProcess a completed send operation.
Constructors
this(TcpConnectionConfig config)
private classTcpListenerState : IShutdownTrackable
Fields
AcceptCallback onAccept
ConnectionCallback onConnection
EventLoop * _loop
SOCKET _socket
Token _token
TcpListenerConfig _config
ushort _localPort
int _lastError
CancelToken _shutdownToken
bool _draining
bool _useOverlappedIoWhether this listener uses overlapped I/O mode (AcceptEx).
Token _prepareTokenPrepare token for polling IOCP completion status.
AcceptExFunc _acceptExAcceptEx function pointer.
GetAcceptExSockaddrsFunc _getAcceptExSockaddrsGetAcceptExSockaddrs function pointer.
int _addressFamilyAddress family of the listen socket (AFINET or AFINET6).
SOCKET _acceptSocketPre-created socket for the pending accept operation.
OVERLAPPED _acceptOverlappedOverlapped structure for pending accept operation.
ubyte[ACCEPT_BUFFER_SIZE] _acceptBufferBuffer for AcceptEx output (local + remote addresses).
bool _acceptInProgressWhether an accept operation is currently in progress.
Methods
void initiateShutdown(CancelToken token) @safe nothrow
void performDrain() @safe nothrow
void forceAbort() @safe nothrow
bool isClosed() @property const @safe nothrow @nogc
bool isOpen() @property const @safe nothrow @nogc
ListenResult listen(ref EventLoop loop, scope const(char)[] host, ushort port) @trusted nothrow
void close() @trusted nothrow
void handleIo(ref EventLoop loop, Token token, IoReady ready) @safe nothrow
TcpListener owner() @safe nothrow
void acceptAvailable() @trusted nothrow
void invokeAccept(Handle clientHandle) @trusted nothrow
void handlePrepare(ref EventLoop loop, Token token) @trusted nothrowHandle prepare phase callback from the event loop.
int associateWithIocp() @trusted nothrowAssociate the listen socket with the event loop's IOCP.
void submitAccept() @trusted nothrowSubmit an AcceptEx operation.
void processAcceptCompletion() @trusted nothrowProcess a completed AcceptEx operation.
Constructors
this(TcpListenerConfig config)
private structAddrinfoRange

Range adapter for iterating over addrinfo linked list.

Fields
addrinfo * current
Methods
bool empty() @property const pure @safe nothrow @nogcCheck if the range is exhausted.
addrinfo * front() @property pure @safe nothrow @nogcGet the current addrinfo entry.
void popFront() pure @safe nothrow @nogcAdvance to the next entry.

Functions 13

private fnListenResult mapListenError(int err) pure @safe nothrow @nogcMap Winsock error code to ListenResult.
private fnConnectResult mapConnectError(int err) pure @safe nothrow @nogcMap Winsock error code to ConnectResult.
private fnAdoptResult mapAdoptError(int err) pure @safe nothrow @nogcMap Winsock error code to AdoptResult.
private fnTcpConnectionConfig validated(TcpConnectionConfig config) pure @safe nothrow @nogcValidate a connection config, returning defaults if invalid.
private fnTcpListenerConfig validated(TcpListenerConfig config) pure @safe nothrow @nogcValidate a listener config, returning defaults if invalid.
private fnconst(char) * copyStringz(scope const(char)[] source, scope char[] buffer) @trusted nothrowCopy a D string slice to a null-terminated C string buffer.
private fnconst(char) * portToString(ushort port, scope char[] buffer) @trusted nothrowConvert a port number to a null-terminated string.
private fnint setNonBlocking(SOCKET sock) @trusted nothrowSet a socket to non-blocking mode.
private fnbool wouldBlock() @trusted nothrowCheck if the last Winsock error indicates the operation would block.
private fnint socketError(SOCKET sock) @trusted nothrowQuery the socket error status.
private fnint mapWsaError(int wsaError) pure @safe nothrow @nogcMap Winsock error code to POSIX-style errno.
private fnushort queryLocalPort(SOCKET sock) @trusted nothrowQuery the local port number for a bound socket.
private fnAddrinfoRange addrinfoRange(addrinfo * first) pure @safe nothrow @nogcCreate a range over an addrinfo linked list.

Variables 4

private enumvarSOMAXCONN = 0x7fffffff

Maximum listen backlog (not in druntime's winsock2).

private enumvarTCP_READ_BUFFER_SIZE = 8192

Size of the internal read/write buffer for overlapped I/O.

private enumvarACCEPT_ADDR_LEN = SOCKADDR_STORAGE.sizeof + 16

Size of address buffer for AcceptEx (sockaddr_storage + 16 bytes padding).

private enumvarACCEPT_BUFFER_SIZE = ACCEPT_ADDR_LEN * 2

Total buffer size for AcceptEx (local + remote addresses).