cia1099 / Cpp-SocketLibrary

C++ Bluetooth and Network socket library.

Cpp-SocketLibrary

A ServerSocket and Socket library for Linux aiming to support both Wifi and Bluetooth communication.

Get Started

1. Optional Step If you want to run this in the provided Docker container, ensure that Docker is installed and running then execute docker build .. Once this is done launch the image and connect to the container.
2. Once in the docker container, or locally and in the base directory of the repo, run make and link the generated object files and headers accordingly.
3. Some general tests can be run using make check. Bluetooth test currently still in progress since I am unable to be the host and client from the same machine

Usage Examples

• TCP Example:

// Create a new Wifi ServerSocket
kt::ServerSocket server(kt::SocketType::Wifi, 56756);

// Create new TCP socket
kt::Socket client("127.0.0.1", 56756, kt::SocketType::Wifi, kt::SocketProtocol::TCP);

// Accept connection to server
kt::Socket serverSocket = server.accept();

const std::string testString = "Test";
serverSocket.send(testString);
const std::string response = client.receiveAmount(testString.size());
// Compare received and sent string values
assert(response == testString);

client.close();
serverSocket.close();
server.close();

• UDP Example:

kt::Socket serverSocket("127.0.0.1", 43567, kt::SocketType::Wifi, kt::SocketProtocol::UDP);
// Which ever socket is acting as the "server" needs to bind, only a single process can be bound 
// to a specific port at a time
serverSocket.bind();

kt::Socket client("127.0.0.1", 43567, kt::SocketType::Wifi, kt::SocketProtocol::UDP);

const std::string testString = "UDP Test";
const char delimiter = '~';
client.send(testString + delimiter);
const std::string response = serverSocket.receiveToDelimiter(delimiter);
assert(response == testString);

serverSocket.close();
client.close();

Known Issues

SIGPIPE Error

• There is a known issue regarding SIGPIPE crashing the programming when send() is called after the remote process has already closed the socket.

• A way to resolve this is to remove the SIGPIPE handler, since we can detect this disconnection when the send() function returns false.

• Disable the SIGPIPE handler using the following code:

#include <signal.h>

...
signal(SIGPIPE, SIG_IGN);
...

NOTE: UDP Read Sizes

• Take care when reading UDP messages. If you do not read the entire length of the message the rest of the data will be lost. Try using receiveAll()/recieveToDelimiter()/receiveAmount() instead of get(), unless you know the amount of data that you are expecting.