/home/fwph/code/wurde/modules/rFlexBase/SerialPort.cpp

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#include <SerialPort.H>

#include <termios.h>
#include <sys/stat.h>

#include <cassert>


#warning Get rid of this
#include <iostream>


using namespace std;


// These are the mappings from integer baud rates to the macros used by the system calls that manipulate the termios struct
static const int g_num_rates = 31;
static const speed_t g_baud_rates[g_num_rates] = {
        B0, B50, B75, B110, B134, B150, B200, B300, B600, B1200,
        B1800, B2400, B4800, B9600, B19200, B38400, B57600, B115200, B230400, B460800,
        B500000, B576000, B921600, B1000000, B1152000, B1500000, B2000000, B2500000, B3000000, B3500000,
  B4000000};
static const int g_speeds[g_num_rates] = {
        0, 50, 75, 110, 134, 150, 200, 300, 600, 1200,
        1800, 2400, 4800, 9600, 19200, 38400, 57600, 115200, 230400, 460800,
        500000, 576000, 921600, 1000000, 1152000, 1500000, 2000000, 2500000, 3000000, 3500000,
  4000000};


SerialPort::SerialPort(const string &filename, const int speed, mode_t mode) :m_filename(filename) {
        assert(speed > 0);

        // Open the port
        m_fd = open(filename.c_str(), mode);
        if (m_fd == -1) {
                cerr << "Could not open serial port " << filename << endl;
                return;
        }

        // Get the terminal info
        struct termios info;
        if (tcgetattr(m_fd, &info) < 0) {
                cerr << "Could not get terminal information for " << filename << endl;
                return;
        }

  // Turn off echo, canonical mode, extended processing, signals, break signal, cr to newline, parity off, 8 bit strip, flow control,
  // size, parity bit, and output processing
  info.c_lflag &= ~(ECHO | ICANON | IEXTEN | ISIG | BRKINT | ICRNL | INPCK | ISTRIP | IXON | CSIZE | PARENB | OPOST);

        // Set size to 8 bits
  info.c_cflag |= CS8;

  // Set time and bytes to enable read at once
  info.c_cc[VTIME] = 0;
  info.c_cc[VMIN] = 0;

        // Actually set the controls on the terminal
        if (tcsetattr(m_fd, TCSAFLUSH, &info) < 0) {
                close(m_fd);
                cerr << "Could not set controls on serial port " << filename << endl;
        }

        setBaudRate(speed);
}


SerialPort::~SerialPort() {
        if (m_fd != -1)
                close(m_fd);
}


int SerialPort::setBaudRate(const int speed) const {
        assert(speed > 0);

        // Set the actual speed to pass into the terminal.
        speed_t baud_rate = baud(speed);

        // Now, get the terminal information and set the speed
        struct termios info;
        if (tcgetattr(m_fd, &info) < 0) {
                cerr << "Could not get terminal information for " << m_filename << endl;
                return baudRate();
        }

        if (cfsetospeed(&info, baud_rate) < 0) {
                cerr << "Could not set the output speed for " << m_filename << endl;
                return baudRate();
        }

        if (cfsetispeed(&info, baud_rate) < 0) {
                cerr << "Could not set the input speed for " << m_filename << endl;
                return baudRate();
        }

        if (tcsetattr(m_fd, TCSAFLUSH, &info) < 0) {
                close(m_fd);
                cerr << "Could not set controls on serial port " << m_filename << endl;
        }

        return rate(baud_rate);
}


int SerialPort::baudRate() const {
        // Open the terminal.  We actually need to check the read device in case someone else has sneakily set the speed.
        struct termios info;
        if (tcgetattr(m_fd, &info) < 0) {
                cerr << "Could not get terminal information for " << m_filename << endl;
                return 0;
        }

        // Get the speeds
        speed_t ospeed = cfgetospeed(&info);
        speed_t ispeed = cfgetispeed(&info);

        // Ensure that they are the same
        if (ospeed != ispeed) {
                cerr << "Input and output speeds are different for " << m_filename << "\n  input: " << rate(ispeed) << "\n  output: " << rate(ospeed) << endl;
                return 0;
        }

        return rate(ospeed);
}


int SerialPort::rate(speed_t baud) {
        for(int i = 0; i < g_num_rates ; ++i)
                if (baud == g_baud_rates[i])
                        return g_speeds[i];

        // Should never get here
        return 0;
}


speed_t SerialPort::baud(const int speed) {
        assert(speed > 0);

        for(int i = g_num_rates - 1; i >= 0; --i)
                if (speed >= g_speeds[i])
                        return g_baud_rates[i];

        // Should never get here
        return B0;
}

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