Refactoring Socket Sample Code: Step 6

After inverting all of the ifs and nesting all the code deeper, you’ll end up with this:

#include <WinSock2.h>
#include <WS2tcpip.h>
#include <Wspiapi.h>

// Need to link with Ws2_32.lib, Mswsock.lib, and Advapi32.lib
#define DEFAULT_BUFLEN 512
#define DEFAULT_PORT "27015"

namespace LegacySockets
{
int Client(const char* server = "localhost") // returns total bytes sent or -1 on error
{
    int totalBytesSent = -1;

    // Initialize Winsock
    WSADATA wsaData;
    int iResult = WSAStartup(MAKEWORD(2,2), &wsaData);
    if (iResult == 0) {
        struct addrinfo hints = {0};
        hints.ai_family   = AF_UNSPEC;
        hints.ai_socktype = SOCK_STREAM;
        hints.ai_protocol = IPPROTO_TCP;

        // Resolve the server address and port
        struct addrinfo* result = NULL;
        iResult = getaddrinfo(server, DEFAULT_PORT, &hints, &result);
        if (iResult == 0) {

            // Attempt to connect to an address until one succeeds
            SOCKET ConnectSocket = INVALID_SOCKET;
            for (struct addrinfo* ptr = result; ptr != NULL; ptr = ptr->ai_next) {

                // Create a SOCKET for connecting to server
                ConnectSocket = socket(ptr->ai_family, ptr->ai_socktype, ptr->ai_protocol);
                if (ConnectSocket != INVALID_SOCKET) {
                    // Connect to server.
                    iResult = connect(ConnectSocket, ptr->ai_addr, (int)ptr->ai_addrlen);
                    if (iResult != SOCKET_ERROR)
                        break;
                    closesocket(ConnectSocket);
                    ConnectSocket = INVALID_SOCKET;
                }
            }

            if (ConnectSocket != INVALID_SOCKET) {
                const char* sendbuf = "this is a longer test";
                // Send an initial buffer
                iResult = send(ConnectSocket, sendbuf, (int)strlen(sendbuf), 0);
                if (iResult != SOCKET_ERROR) {

                    totalBytesSent = iResult;

                    // shutdown the connection since no more data will be sent
                    iResult = shutdown(ConnectSocket, SD_SEND);
                    if (iResult != SOCKET_ERROR) {
                        // Receive until the peer closes the connection
                        do {
                            char recvbuf[DEFAULT_BUFLEN];
                            int recvbuflen = DEFAULT_BUFLEN;
                            iResult = recv(ConnectSocket, recvbuf, recvbuflen, 0);
                        } while (iResult > 0);
                    }
                }
                // cleanup
                closesocket(ConnectSocket);
            }
            freeaddrinfo(result);
        }
        WSACleanup();
    }
    return totalBytesSent;
}
}

The code coverage for this file is now 100%.

Are we done? Not quite: we could extract a function that does all the connecting attempts; we could get rid of those macros; we could remove or move those somewhat useless comments.

Let’s do all of that (still making sure that the test passes), and then click Next.