SSH ChannelReceiveUntilMatchN (Match Any of Several Prompts)

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Demonstrates ChannelReceiveUntilMatchN, which receives until any one of several patterns is matched. This is useful when driving an interactive session where the shell prompt differs from device to device.

Note: This example deliberately requests a PTY. Matching a shell prompt only works in an interactive session — without a PTY the shell runs non-interactively and never prints a prompt at all. For scripted use, omit the PTY and match on a marker your own command echoes.

#include <CkSsh.h>
#include <CkStringArray.h>

void ChilkatSample(void)
    {
    bool success = false;

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

    //  Demonstrates ChannelReceiveUntilMatchN, which receives until ANY one of several patterns is
    //  matched.  This is useful when driving an interactive session where the shell prompt varies
    //  from device to device.
    //  
    //  Note: This example deliberately DOES request a PTY.  Matching a shell prompt only works in an
    //  interactive session -- without a PTY the shell runs non-interactively and never prints a
    //  prompt at all.  For scripted use where no prompt is needed, omit the PTY and match on a
    //  marker your own command echoes instead.

    CkSsh ssh;

    //  The remote shell prompt may be any of these, depending on the device.
    CkStringArray saPrompts;
    saPrompts.Append("~$");
    saPrompts.Append("mars#");
    saPrompts.Append("jupiter%");
    saPrompts.Append("chilkat$");
    saPrompts.Append("admin>");

    const char *hostname = "ssh.example.com";
    int port = 22;
    success = ssh.Connect(hostname,port);
    if (success == false) {
        std::cout << ssh.lastErrorText() << "\r\n";
        return;
    }

    //  Normally you would not hard-code the password in source.  You should instead obtain it
    //  from an interactive prompt, environment variable, or a secrets vault.
    const char *password = "mySshPassword";

    success = ssh.AuthenticatePw("mySshLogin",password);
    if (success == false) {
        std::cout << ssh.lastErrorText() << "\r\n";
        return;
    }

    int channelNum = ssh.OpenSessionChannel();
    if (channelNum < 0) {
        std::cout << ssh.lastErrorText() << "\r\n";
        return;
    }

    //  Request a pseudo-terminal so the shell runs interactively and prints prompts.  A "dumb"
    //  terminal is used so that ANSI escape sequences are not mixed into the output.
    const char *termType = "dumb";
    int widthInChars = 120;
    int heightInChars = 40;
    int pixWidth = 0;
    int pixHeight = 0;
    success = ssh.SendReqPty(channelNum,termType,widthInChars,heightInChars,pixWidth,pixHeight);
    if (success == false) {
        std::cout << ssh.lastErrorText() << "\r\n";
        return;
    }

    success = ssh.SendReqShell(channelNum);
    if (success == false) {
        std::cout << ssh.lastErrorText() << "\r\n";
        return;
    }

    //  IMPORTANT: Set a read timeout before receiving until a match.  ReadTimeoutMs defaults to 0,
    //  which means no limit -- without it, this call waits forever if the received data never
    //  contains a match.
    ssh.put_ReadTimeoutMs(15000);

    bool caseSensitive = true;

    //  Read the initial login text up to the first prompt.
    success = ssh.ChannelReceiveUntilMatchN(channelNum,saPrompts,"utf-8",caseSensitive);
    if (success == false) {
        std::cout << ssh.lastErrorText() << "\r\n";
        return;
    }

    const char *cmdOutput = ssh.getReceivedText(channelNum,"utf-8");
    if (ssh.get_LastMethodSuccess() == false) {
        std::cout << ssh.lastErrorText() << "\r\n";
        return;
    }

    std::cout << cmdOutput << "\r\n";

    //  ---- 1st command ----
    success = ssh.ChannelSendString(channelNum,"cd /tmp\n","utf-8");
    if (success == false) {
        std::cout << ssh.lastErrorText() << "\r\n";
        return;
    }

    success = ssh.ChannelReceiveUntilMatchN(channelNum,saPrompts,"utf-8",caseSensitive);
    if (success == false) {
        std::cout << ssh.lastErrorText() << "\r\n";
        return;
    }

    //  Retrieving the text also clears the receive buffer, which matters: if a prompt were left
    //  buffered, the next receive would match it immediately and return the wrong output.
    cmdOutput = ssh.getReceivedText(channelNum,"utf-8");
    if (ssh.get_LastMethodSuccess() == false) {
        std::cout << ssh.lastErrorText() << "\r\n";
        return;
    }

    std::cout << cmdOutput << "\r\n";

    //  ---- 2nd command ----
    success = ssh.ChannelSendString(channelNum,"ls\n","utf-8");
    if (success == false) {
        std::cout << ssh.lastErrorText() << "\r\n";
        return;
    }

    success = ssh.ChannelReceiveUntilMatchN(channelNum,saPrompts,"utf-8",caseSensitive);
    if (success == false) {
        std::cout << ssh.lastErrorText() << "\r\n";
        return;
    }

    cmdOutput = ssh.getReceivedText(channelNum,"utf-8");
    if (ssh.get_LastMethodSuccess() == false) {
        std::cout << ssh.lastErrorText() << "\r\n";
        return;
    }

    std::cout << cmdOutput << "\r\n";

    //  Finish the session.
    success = ssh.ChannelSendEof(channelNum);
    if (success == false) {
        std::cout << ssh.lastErrorText() << "\r\n";
        return;
    }

    success = ssh.ChannelReceiveToClose(channelNum);
    if (success == false) {
        std::cout << ssh.lastErrorText() << "\r\n";
        return;
    }

    cmdOutput = ssh.getReceivedText(channelNum,"utf-8");
    if (ssh.get_LastMethodSuccess() == false) {
        std::cout << ssh.lastErrorText() << "\r\n";
        return;
    }

    std::cout << cmdOutput << "\r\n";

    ssh.Disconnect();
    }