(Unicode C) POP3 over Multiple Hop SSH

Demonstrates how to read POP3 email (using TCP or TLS) tunneled through mulitple-hop SSH. The scheme looks like this:

Application => ServerSSH1 => ServerSSH2 => POP3Server

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#include <C_CkSshW.h>
#include <C_CkMailManW.h>
#include <C_CkEmailW.h>

void ChilkatSample(void)
    {
    HCkSshW ssh1;
    BOOL success;
    HCkSshW ssh2;
    HCkMailManW mailman;
    int numMessages;
    int i;
    HCkEmailW email;

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    ssh1 = CkSshW_Create();

    // Connect directly to the 1st SSH server.
    success = CkSshW_Connect(ssh1,L"serverssh1.com",22);
    if (success != TRUE) {
        wprintf(L"%s\n",CkSshW_lastErrorText(ssh1));
        CkSshW_Dispose(ssh1);
        return;
    }

    // Authenticate using login/password:
    success = CkSshW_AuthenticatePw(ssh1,L"ssh1Login",L"ssh1Password");
    if (success != TRUE) {
        wprintf(L"%s\n",CkSshW_lastErrorText(ssh1));
        CkSshW_Dispose(ssh1);
        return;
    }

    // Connect through the 1st SSH connection to reach a 2nd SSH server.
    // Note: Any number of SSH connections may be simultaneously tunneled through a single
    // existing SSH connection.
    ssh2 = CkSshW_Create();
    success = CkSshW_ConnectThroughSsh(ssh2,ssh1,L"serverssh2.com",22);
    if (success != TRUE) {
        wprintf(L"%s\n",CkSshW_lastErrorText(ssh2));
        CkSshW_Dispose(ssh1);
        CkSshW_Dispose(ssh2);
        return;
    }

    // Authenticate with ssh2...
    success = CkSshW_AuthenticatePw(ssh2,L"ssh2Login",L"ssh2Password");
    if (success != TRUE) {
        wprintf(L"%s\n",CkSshW_lastErrorText(ssh2));
        CkSshW_Dispose(ssh1);
        CkSshW_Dispose(ssh2);
        return;
    }

    mailman = CkMailManW_Create();

    // Tell the mailman object to connect to the POP3 server though the ssh2 tunnel (which itself is routed through ssh1).
    // The connection looks like this:  Application => ServerSSH1 => ServerSSH2 => POP3Server
    success = CkMailManW_UseSsh(mailman,ssh2);
    if (success != TRUE) {
        wprintf(L"%s\n",CkMailManW_lastErrorText(mailman));
        CkSshW_Dispose(ssh1);
        CkSshW_Dispose(ssh2);
        CkMailManW_Dispose(mailman);
        return;
    }

    // Set the POP3 server's hostname
    CkMailManW_putMailHost(mailman,L"pop.someMailServer.com");

    // Set the POP3 login/password.
    CkMailManW_putPopUsername(mailman,L"myLogin");
    CkMailManW_putPopPassword(mailman,L"myPassword");

    // Establish the POP3 connection through the ssh2 tunnel.
    success = CkMailManW_Pop3BeginSession(mailman);
    if (success != TRUE) {
        wprintf(L"%s\n",CkMailManW_lastErrorText(mailman));
        CkSshW_Dispose(ssh1);
        CkSshW_Dispose(ssh2);
        CkMailManW_Dispose(mailman);
        return;
    }

    // Get the number of messages in the mailbox.
    numMessages = CkMailManW_GetMailboxCount(mailman);

    i = 1;

    while (i <= numMessages) {

        email = CkMailManW_FetchByMsgnum(mailman,i);
        if (CkMailManW_getLastMethodSuccess(mailman) != TRUE) {
            wprintf(L"%s\n",CkMailManW_lastErrorText(mailman));
            CkSshW_Dispose(ssh1);
            CkSshW_Dispose(ssh2);
            CkMailManW_Dispose(mailman);
            return;
        }

        wprintf(L"%s: %s\n\n",CkEmailW_ck_from(email),CkEmailW_subject(email));
        CkEmailW_Dispose(email);

        i = i + 1;
    }

    // Close the connection with the POP3 server.  (This closes the tunnel through ssh2)
    // The connection with ssh2 is still alive, and may be used for more connections.
    success = CkMailManW_Pop3EndSession(mailman);

    // Close the connection with ssh2.  (This closes the the tunnel through ssh1.)
    // The connection with ssh1 is still alive, and may be used for more connections.

    CkSshW_Disconnect(ssh2);

    CkSshW_Disconnect(ssh1);


    CkSshW_Dispose(ssh1);
    CkSshW_Dispose(ssh2);
    CkMailManW_Dispose(mailman);

    }