Server.swift

import Darwin

typealias Socket        = Int32
typealias SocketAddress = sockaddr_in
typealias SocketPort    = UInt16

public enum HTTPError : ErrorType {
    case Binding
    case Address
}

public class HTTP {
    var server:Socket   = 0
    var buffer:Int      = 1024
    var address:SocketAddress?
    
    func socket_write(client:Socket, _ output:String) {
        output.withCString { bytes in
            send(client, bytes, Int(strlen(bytes)), 0)
        }
    }
    
    func bindSetup() throws {
        guard var address   = address else { throw HTTPError.Address }
        let pointer         = UnsafeMutablePointer<sockaddr>(withUnsafeMutablePointer(&address, { $0 }))
        let binding         = bind(server, pointer, socklen_t(UInt8(sizeof(SocketAddress))))

        if binding < 0 {
            throw HTTPError.Binding
        }
    }
    
    init(port:SocketPort) {
        server = socket(AF_INET, Socket(SOCK_STREAM), 0)
        
        let htons = (port << 8) + (port >> 8)
        
        address = sockaddr_in(
            sin_len     : __uint8_t(sizeof(SocketAddress)),
            sin_family  : sa_family_t(AF_INET),
            sin_port    : htons,
            sin_addr    : in_addr(s_addr: in_addr_t(0)),
            sin_zero    : (0, 0, 0, 0, 0, 0, 0, 0)
        )
        
        setsockopt(server, SOL_SOCKET, SO_RCVBUF, &buffer, socklen_t(sizeof(Int)))
        
        do {
            try bindSetup()
        }
        catch {
            fatalError("Unable to bind to port \(port)")
        }
    }
    
    func run() {
        print("Pilot Version \(VERSION)")
        print("Running server on port: \(port)")
        
        while (true) {
            if (listen(server, 10) < 0) {
                exit(1)
            }
            
            let client = accept(server, nil, nil)
            
            let message         = "Hello World"
            let contentLength   = message.utf8.count
            
            socket_write(client, "HTTP/1.1 200 OK\n")
            socket_write(client, "Server: Pilot v\(VERSION)\n")
            socket_write(client, "Content-length: \(contentLength)\n")
            socket_write(client, "Content-type: text-plain\n")
            socket_write(client, "\r\n")
            
            socket_write(client, message)
            
            close(client)
        }
    }
}