TcpServerTransport¶

class nmeasim::io::TcpServerTransport · Library API

Listens for TCP clients and sends every line to all of them.

#include <nmeasim/io/transports/tcp_server_transport.hpp>

Inherits nmeasim::io::Transport

Declared in src/io/include/nmeasim/io/transports/tcp_server_transport.hpp (line 30)

Any number of clients may connect; each receives every line written after it connected. A client that disconnects or reports a socket error is removed at once, and data received from clients is discarded, since the simulator only talks. client_count_changed is emitted whenever a client is added or removed. Errors while accepting a connection are reported through error_occurred and leave the server open.

Summary¶

Public member functions

Name	Description
`TcpServerTransport()`	Creates a closed server; it starts listening in `open`.
`~TcpServerTransport()`	Destroys the transport, closing it and every client connection first.
`description()`	Returns the bind address and the port.
`open()`	Starts listening on the bind address and port.
`close()`	Closes every client connection, stops listening and moves to `State::Closed`.
`write()`	Queues `line` on the socket of every connected client.
`client_count()`	Returns the number of connected clients.
`port()`	Returns the TCP port of the server.

Private member functions

Name	Description
`accept_connections()`	Takes every pending connection from the server, starts tracking it and emits `client_count_changed`.
`drop_client()`	Stops tracking `client`, schedules its deletion and emits `client_count_changed`.

Private data members

Name	Description
`server_`	The listening socket; the Qt parent of every accepted client socket.
`clients_`	Connected clients, in order of connection.
`requested_port_`	Port passed to the constructor; 0 for a port chosen by the operating system.
`bind_address_`	Local address to listen on.

Public member functions¶

TcpServerTransport()¶

explicit TcpServerTransport(
    quint16 port,
    QHostAddress bind_address = QHostAddress::Any,
    QObject* parent = nullptr)

Creates a closed server; it starts listening in open.

Parameters

Name	Type	Description
`port`	`quint16`	TCP port to listen on; 0 asks the operating system for a free port, which `port` returns once the server is open.
`bind_address`	`QHostAddress`	Local address to listen on. The default `QHostAddress::Any` accepts connections on every interface, IPv4 and IPv6; `QHostAddress::LocalHost` accepts local connections only.
`parent`	`QObject*`	Qt parent that owns the transport; null leaves ownership to the caller.

Declared in src/io/include/nmeasim/io/transports/tcp_server_transport.hpp:42 · defined in src/io/src/transports/tcp_server_transport.cpp:12

~TcpServerTransport()¶

~TcpServerTransport() override

Destroys the transport, closing it and every client connection first.

Declared in src/io/include/nmeasim/io/transports/tcp_server_transport.hpp:45 · defined in src/io/src/transports/tcp_server_transport.cpp:19

description()¶

QString description() const override

Returns the bind address and the port.

Returns QString: For example TCP server on 127.0.0.1:10110, with the port actually listened on while open.

Overrides description · Declared in src/io/include/nmeasim/io/transports/tcp_server_transport.hpp:51 · defined in src/io/src/transports/tcp_server_transport.cpp:23

open()¶

bool open() override

Starts listening on the bind address and port.

Returns true at once when already open. Fails with Cannot listen on <address>:<port> and the reason, for example when the port is already in use or needs privileges.

Returns bool: True when the server listens, false when listening failed.

Overrides open · Declared in src/io/include/nmeasim/io/transports/tcp_server_transport.hpp:58 · defined in src/io/src/transports/tcp_server_transport.cpp:27

close()¶

void close() override

Closes every client connection, stops listening and moves to State::Closed.

Emits client_count_changed with 0, even when no client was connected.

Overrides close · Declared in src/io/include/nmeasim/io/transports/tcp_server_transport.hpp:62 · defined in src/io/src/transports/tcp_server_transport.cpp:43

write()¶

void write(const QByteArray& line) override

Queues line on the socket of every connected client.

Does nothing when no client is connected. Each socket sends asynchronously; the transport sets no limit on how much a slow client can have queued.

Parameters

Name	Type	Description
`line`	`const QByteArray&`	One complete line, terminator included.

Overrides write · Declared in src/io/include/nmeasim/io/transports/tcp_server_transport.hpp:69 · defined in src/io/src/transports/tcp_server_transport.cpp:58

client_count()¶

int client_count() const override

Returns the number of connected clients.

Returns int: The clients accepted and not yet removed; 0 while closed.

Overrides client_count · Declared in src/io/include/nmeasim/io/transports/tcp_server_transport.hpp:73 · defined in src/io/src/transports/tcp_server_transport.cpp:69

port()¶

quint16 port() const

Returns the TCP port of the server.

Returns quint16: The port actually listened on while open, which is the one chosen by the operating system when 0 was requested; otherwise the requested port.

Declared in src/io/include/nmeasim/io/transports/tcp_server_transport.hpp:79 · defined in src/io/src/transports/tcp_server_transport.cpp:73

Private member functions¶

accept_connections()¶

void accept_connections()

Takes every pending connection from the server, starts tracking it and emits client_count_changed.

Connected to QTcpServer::newConnection.

Declared in src/io/include/nmeasim/io/transports/tcp_server_transport.hpp:84 · defined in src/io/src/transports/tcp_server_transport.cpp:77

drop_client()¶

void drop_client(QTcpSocket* client)

Stops tracking client, schedules its deletion and emits client_count_changed.

Connected to the disconnected and errorOccurred signals of every client; a client that is no longer tracked is ignored, so a client reporting both is removed once.

Parameters