serial.h

/*!
 * \file serial/serial.h
 * \author  William Woodall <wjwwood@gmail.com>
 * \author  John Harrison   <ash.gti@gmail.com>
 * \version 0.1
 *
 * \section LICENSE
 *
 * The MIT License
 *
 * Copyright (c) 2012 William Woodall
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 *
 * \section DESCRIPTION
 *
 * This provides a cross platform interface for interacting with Serial Ports.
 */

#ifndef SERIAL_H
#define SERIAL_H

#include <limits>
#include <vector>
#include <string>
#include <cstring>
#include <sstream>
#include <exception>
#include <stdexcept>
#include "v8stdint.h"

#define THROW(exceptionClass, message) throw exceptionClass(__FILE__, \
__LINE__, (message) )

namespace serial {

/*!
 * Enumeration defines the possible bytesizes for the serial port.
 */
typedef enum {
  fivebits = 5,
  sixbits = 6,
  sevenbits = 7,
  eightbits = 8
} bytesize_t;

/*!
 * Enumeration defines the possible parity types for the serial port.
 */
typedef enum {
  parity_none = 0,
  parity_odd = 1,
  parity_even = 2,
  parity_mark = 3,
  parity_space = 4
} parity_t;

/*!
 * Enumeration defines the possible stopbit types for the serial port.
 */
typedef enum {
  stopbits_one = 1,
  stopbits_two = 2,
  stopbits_one_point_five
} stopbits_t;

/*!
 * Enumeration defines the possible flowcontrol types for the serial port.
 */
typedef enum {
  flowcontrol_none = 0,
  flowcontrol_software,
  flowcontrol_hardware
} flowcontrol_t;

/*!
 * Structure for setting the timeout of the serial port, times are
 * in milliseconds.
 *
 * In order to disable the interbyte timeout, set it to Timeout::max().
 */
struct Timeout {
#ifdef max
# undef max
#endif
  static uint32_t max() {return std::numeric_limits<uint32_t>::max();}
  /*!
   * Convenience function to generate Timeout structs using a
   * single absolute timeout.
   *
   * \param timeout A long that defines the time in milliseconds until a
   * timeout occurs after a call to read or write is made.
   *
   * \return Timeout struct that represents this simple timeout provided.
   */
  static Timeout simpleTimeout(uint32_t timeout) {
    return Timeout(max(), timeout, 0, timeout, 0);
  }

  /*! Number of milliseconds between bytes received to timeout on. */
  uint32_t inter_byte_timeout;
  /*! A constant number of milliseconds to wait after calling read. */
  uint32_t read_timeout_constant;
  /*! A multiplier against the number of requested bytes to wait after
   *  calling read.
   */
  uint32_t read_timeout_multiplier;
  /*! A constant number of milliseconds to wait after calling write. */
  uint32_t write_timeout_constant;
  /*! A multiplier against the number of requested bytes to wait after
   *  calling write.
   */
  uint32_t write_timeout_multiplier;

  explicit Timeout (uint32_t inter_byte_timeout_=0,
                    uint32_t read_timeout_constant_=0,
                    uint32_t read_timeout_multiplier_=0,
                    uint32_t write_timeout_constant_=0,
                    uint32_t write_timeout_multiplier_=0)
  : inter_byte_timeout(inter_byte_timeout_),
    read_timeout_constant(read_timeout_constant_),
    read_timeout_multiplier(read_timeout_multiplier_),
    write_timeout_constant(write_timeout_constant_),
    write_timeout_multiplier(write_timeout_multiplier_)
  {}
};

/*!
 * Class that provides a portable serial port interface.
 */
class Serial {
public:
  /*!
   * Creates a Serial object and opens the port if a port is specified,
   * otherwise it remains closed until serial::Serial::open is called.
   *
   * \param port A std::string containing the address of the serial port,
   *        which would be something like 'COM1' on Windows and '/dev/ttyS0'
   *        on Linux.
   *
   * \param baudrate An unsigned 32-bit integer that represents the baudrate
   *
   * \param timeout A serial::Timeout struct that defines the timeout
   * conditions for the serial port. \see serial::Timeout
   *
   * \param bytesize Size of each byte in the serial transmission of data,
   * default is eightbits, possible values are: fivebits, sixbits, sevenbits,
   * eightbits
   *
   * \param parity Method of parity, default is parity_none, possible values
   * are: parity_none, parity_odd, parity_even
   *
   * \param stopbits Number of stop bits used, default is stopbits_one,
   * possible values are: stopbits_one, stopbits_one_point_five, stopbits_two
   *
   * \param flowcontrol Type of flowcontrol used, default is
   * flowcontrol_none, possible values are: flowcontrol_none,
   * flowcontrol_software, flowcontrol_hardware
   *
   * \throw serial::PortNotOpenedException
   * \throw serial::IOException
   * \throw std::invalid_argument
   */
  Serial (const std::string &port = "",
          uint32_t baudrate = 9600,
          Timeout timeout = Timeout(),
          bytesize_t bytesize = eightbits,
          parity_t parity = parity_none,
          stopbits_t stopbits = stopbits_one,
          flowcontrol_t flowcontrol = flowcontrol_none);

  /*! Destructor */
  virtual ~Serial ();

  /*!
   * Opens the serial port as long as the port is set and the port isn't
   * already open.
   *
   * If the port is provided to the constructor then an explicit call to open
   * is not needed.
   *
   * \see Serial::Serial
   *
   * \throw std::invalid_argument
   * \throw serial::SerialException
   * \throw serial::IOException
   */
  void
  open ();

  /*! Gets the open status of the serial port.
   *
   * \return Returns true if the port is open, false otherwise.
   */
  bool
  isOpen () const;

  /*! Closes the serial port. */
  void
  close ();

  /*! Return the number of characters in the buffer. */
  size_t
  available ();

  /*! Block until there is serial data to read or read_timeout_constant
   * number of milliseconds have elapsed. The return value is true when
   * the function exits with the port in a readable state, false otherwise
   * (due to timeout or select interruption). */
  bool
  waitReadable ();

  /*! Block for a period of time corresponding to the transmission time of
   * count characters at present serial settings. This may be used in con-
   * junction with waitReadable to read larger blocks of data from the
   * port. */
  void
  waitByteTimes (size_t count);

  /*! Read a given amount of bytes from the serial port into a given buffer.
   *
   * The read function will return in one of three cases:
   *  * The number of requested bytes was read.
   *    * In this case the number of bytes requested will match the size_t
   *      returned by read.
   *  * A timeout occurred, in this case the number of bytes read will not
   *    match the amount requested, but no exception will be thrown.  One of
   *    two possible timeouts occurred:
   *    * The inter byte timeout expired, this means that number of
   *      milliseconds elapsed between receiving bytes from the serial port
   *      exceeded the inter byte timeout.
   *    * The total timeout expired, which is calculated by multiplying the
   *      read timeout multiplier by the number of requested bytes and then
   *      added to the read timeout constant.  If that total number of
   *      milliseconds elapses after the initial call to read a timeout will
   *      occur.
   *  * An exception occurred, in this case an actual exception will be thrown.
   *
   * \param buffer An uint8_t array of at least the requested size.
   * \param size A size_t defining how many bytes to be read.
   *
   * \return A size_t representing the number of bytes read as a result of the
   *         call to read.
   *
   * \throw serial::PortNotOpenedException
   * \throw serial::SerialException
   */
  size_t
  read (uint8_t *buffer, size_t size);

  /*! Read a given amount of bytes from the serial port into a give buffer.
   *
   * \param buffer A reference to a std::vector of uint8_t.
   * \param size A size_t defining how many bytes to be read.
   *
   * \return A size_t representing the number of bytes read as a result of the
   *         call to read.
   *
   * \throw serial::PortNotOpenedException
   * \throw serial::SerialException
   */
  size_t
  read (std::vector<uint8_t> &buffer, size_t size = 1);

  /*! Read a given amount of bytes from the serial port into a give buffer.
   *
   * \param buffer A reference to a std::string.
   * \param size A size_t defining how many bytes to be read.
   *
   * \return A size_t representing the number of bytes read as a result of the
   *         call to read.
   *
   * \throw serial::PortNotOpenedException
   * \throw serial::SerialException
   */
  size_t
  read (std::string &buffer, size_t size = 1);

  /*! Read a given amount of bytes from the serial port and return a string
   *  containing the data.
   *
   * \param size A size_t defining how many bytes to be read.
   *
   * \return A std::string containing the data read from the port.
   *
   * \throw serial::PortNotOpenedException
   * \throw serial::SerialException
   */
  std::string
  read (size_t size = 1);

  /*! Reads in a line or until a given delimiter has been processed.
   *
   * Reads from the serial port until a single line has been read.
   *
   * \param buffer A std::string reference used to store the data.
   * \param size A maximum length of a line, defaults to 65536 (2^16)
   * \param eol A string to match against for the EOL.
   *
   * \return A size_t representing the number of bytes read.
   *
   * \throw serial::PortNotOpenedException
   * \throw serial::SerialException
   */
  size_t
  readline (std::string &buffer, size_t size = 65536, std::string eol = "\n");

  /*! Reads in a line or until a given delimiter has been processed.
   *
   * Reads from the serial port until a single line has been read.
   *
   * \param size A maximum length of a line, defaults to 65536 (2^16)
   * \param eol A string to match against for the EOL.
   *
   * \return A std::string containing the line.
   *
   * \throw serial::PortNotOpenedException
   * \throw serial::SerialException
   */
  std::string
  readline (size_t size = 65536, std::string eol = "\n");

  /*! Reads in multiple lines until the serial port times out.
   *
   * This requires a timeout > 0 before it can be run. It will read until a
   * timeout occurs and return a list of strings.
   *
   * \param size A maximum length of combined lines, defaults to 65536 (2^16)
   *
   * \param eol A string to match against for the EOL.
   *
   * \return A vector<string> containing the lines.
   *
   * \throw serial::PortNotOpenedException
   * \throw serial::SerialException
   */
  std::vector<std::string>
  readlines (size_t size = 65536, std::string eol = "\n");

  /*! Write a string to the serial port.
   *
   * \param data A const reference containing the data to be written
   * to the serial port.
   *
   * \param size A size_t that indicates how many bytes should be written from
   * the given data buffer.
   *
   * \return A size_t representing the number of bytes actually written to
   * the serial port.
   *
   * \throw serial::PortNotOpenedException
   * \throw serial::SerialException
   * \throw serial::IOException
   */
  size_t
  write (const uint8_t *data, size_t size);

  /*! Write a string to the serial port.
   *
   * \param data A const reference containing the data to be written
   * to the serial port.
   *
   * \return A size_t representing the number of bytes actually written to
   * the serial port.
   *
   * \throw serial::PortNotOpenedException
   * \throw serial::SerialException
   * \throw serial::IOException
   */
  size_t
  write (const std::vector<uint8_t> &data);

  /*! Write a string to the serial port.
   *
   * \param data A const reference containing the data to be written
   * to the serial port.
   *
   * \return A size_t representing the number of bytes actually written to
   * the serial port.
   *
   * \throw serial::PortNotOpenedException
   * \throw serial::SerialException
   * \throw serial::IOException
   */
  size_t
  write (const std::string &data);

  /*! Sets the serial port identifier.
   *
   * \param port A const std::string reference containing the address of the
   * serial port, which would be something like 'COM1' on Windows and
   * '/dev/ttyS0' on Linux.
   *
   * \throw std::invalid_argument
   */
  void
  setPort (const std::string &port);

  /*! Gets the serial port identifier.
   *
   * \see Serial::setPort
   *
   * \throw std::invalid_argument
   */
  std::string
  getPort () const;

  /*! Sets the timeout for reads and writes using the Timeout struct.
   *
   * There are two timeout conditions described here:
   *  * The inter byte timeout:
   *    * The inter_byte_timeout component of serial::Timeout defines the
   *      maximum amount of time, in milliseconds, between receiving bytes on
   *      the serial port that can pass before a timeout occurs.  Setting this
   *      to zero will prevent inter byte timeouts from occurring.
   *  * Total time timeout:
   *    * The constant and multiplier component of this timeout condition,
   *      for both read and write, are defined in serial::Timeout.  This
   *      timeout occurs if the total time since the read or write call was
   *      made exceeds the specified time in milliseconds.
   *    * The limit is defined by multiplying the multiplier component by the
   *      number of requested bytes and adding that product to the constant
   *      component.  In this way if you want a read call, for example, to
   *      timeout after exactly one second regardless of the number of bytes
   *      you asked for then set the read_timeout_constant component of
   *      serial::Timeout to 1000 and the read_timeout_multiplier to zero.
   *      This timeout condition can be used in conjunction with the inter
   *      byte timeout condition with out any problems, timeout will simply
   *      occur when one of the two timeout conditions is met.  This allows
   *      users to have maximum control over the trade-off between
   *      responsiveness and efficiency.
   *
   * Read and write functions will return in one of three cases.  When the
   * reading or writing is complete, when a timeout occurs, or when an
   * exception occurs.
   *
   * A timeout of 0 enables non-blocking mode.
   *
   * \param timeout A serial::Timeout struct containing the inter byte
   * timeout, and the read and write timeout constants and multipliers.
   *
   * \see serial::Timeout
   */
  void
  setTimeout (Timeout &timeout);

  /*! Sets the timeout for reads and writes. */
  void
  setTimeout (uint32_t inter_byte_timeout, uint32_t read_timeout_constant,
              uint32_t read_timeout_multiplier, uint32_t write_timeout_constant,
              uint32_t write_timeout_multiplier)
  {
    Timeout timeout(inter_byte_timeout, read_timeout_constant,
                    read_timeout_multiplier, write_timeout_constant,
                    write_timeout_multiplier);
    return setTimeout(timeout);
  }

  /*! Gets the timeout for reads in seconds.
   *
   * \return A Timeout struct containing the inter_byte_timeout, and read
   * and write timeout constants and multipliers.
   *
   * \see Serial::setTimeout
   */
  Timeout
  getTimeout () const;

  /*! Sets the baudrate for the serial port.
   *
   * Possible baudrates depends on the system but some safe baudrates include:
   * 110, 300, 600, 1200, 2400, 4800, 9600, 14400, 19200, 28800, 38400, 56000,
   * 57600, 115200
   * Some other baudrates that are supported by some comports:
   * 128000, 153600, 230400, 256000, 460800, 500000, 921600
   *
   * \param baudrate An integer that sets the baud rate for the serial port.
   *
   * \throw std::invalid_argument
   */
  void
  setBaudrate (uint32_t baudrate);

  /*! Gets the baudrate for the serial port.
   *
   * \return An integer that sets the baud rate for the serial port.
   *
   * \see Serial::setBaudrate
   *
   * \throw std::invalid_argument
   */
  uint32_t
  getBaudrate () const;

  /*! Sets the bytesize for the serial port.
   *
   * \param bytesize Size of each byte in the serial transmission of data,
   * default is eightbits, possible values are: fivebits, sixbits, sevenbits,
   * eightbits
   *
   * \throw std::invalid_argument
   */
  void
  setBytesize (bytesize_t bytesize);

  /*! Gets the bytesize for the serial port.
   *
   * \see Serial::setBytesize
   *
   * \throw std::invalid_argument
   */
  bytesize_t
  getBytesize () const;

  /*! Sets the parity for the serial port.
   *
   * \param parity Method of parity, default is parity_none, possible values
   * are: parity_none, parity_odd, parity_even
   *
   * \throw std::invalid_argument
   */
  void
  setParity (parity_t parity);

  /*! Gets the parity for the serial port.
   *
   * \see Serial::setParity
   *
   * \throw std::invalid_argument
   */
  parity_t
  getParity () const;

  /*! Sets the stopbits for the serial port.
   *
   * \param stopbits Number of stop bits used, default is stopbits_one,
   * possible values are: stopbits_one, stopbits_one_point_five, stopbits_two
   *
   * \throw std::invalid_argument
   */
  void
  setStopbits (stopbits_t stopbits);

  /*! Gets the stopbits for the serial port.
   *
   * \see Serial::setStopbits
   *
   * \throw std::invalid_argument
   */
  stopbits_t
  getStopbits () const;

  /*! Sets the flow control for the serial port.
   *
   * \param flowcontrol Type of flowcontrol used, default is flowcontrol_none,
   * possible values are: flowcontrol_none, flowcontrol_software,
   * flowcontrol_hardware
   *
   * \throw std::invalid_argument
   */
  void
  setFlowcontrol (flowcontrol_t flowcontrol);

  /*! Gets the flow control for the serial port.
   *
   * \see Serial::setFlowcontrol
   *
   * \throw std::invalid_argument
   */
  flowcontrol_t
  getFlowcontrol () const;

  /*! Flush the input and output buffers */
  void
  flush ();

  /*! Flush only the input buffer */
  void
  flushInput ();

  /*! Flush only the output buffer */
  void
  flushOutput ();

  /*! Sends the RS-232 break signal.  See tcsendbreak(3). */
  void
  sendBreak (int duration);

  /*! Set the break condition to a given level.  Defaults to true. */
  void
  setBreak (bool level = true);

  /*! Set the RTS handshaking line to the given level.  Defaults to true. */
  void
  setRTS (bool level = true);

  /*! Set the DTR handshaking line to the given level.  Defaults to true. */
  void
  setDTR (bool level = true);

  /*!
   * Blocks until CTS, DSR, RI, CD changes or something interrupts it.
   *
   * Can throw an exception if an error occurs while waiting.
   * You can check the status of CTS, DSR, RI, and CD once this returns.
   * Uses TIOCMIWAIT via ioctl if available (mostly only on Linux) with a
   * resolution of less than +-1ms and as good as +-0.2ms.  Otherwise a
   * polling method is used which can give +-2ms.
   *
   * \return Returns true if one of the lines changed, false if something else
   * occurred.
   *
   * \throw SerialException
   */
  bool
  waitForChange ();

  /*! Returns the current status of the CTS line. */
  bool
  getCTS ();

  /*! Returns the current status of the DSR line. */
  bool
  getDSR ();

  /*! Returns the current status of the RI line. */
  bool
  getRI ();

  /*! Returns the current status of the CD line. */
  bool
  getCD ();

private:
  // Disable copy constructors
  Serial(const Serial&);
  Serial& operator=(const Serial&);

  // Pimpl idiom, d_pointer
  class SerialImpl;
  SerialImpl *pimpl_;

  // Scoped Lock Classes
  class ScopedReadLock;
  class ScopedWriteLock;

  // Read common function
  size_t
  read_ (uint8_t *buffer, size_t size);
  // Write common function
  size_t
  write_ (const uint8_t *data, size_t length);

};

class SerialException : public std::exception
{
  // Disable copy constructors
  SerialException& operator=(const SerialException&);
  std::string e_what_;
public:
  SerialException (const char *description) {
      std::stringstream ss;
      ss << "SerialException " << description << " failed.";
      e_what_ = ss.str();
  }
  SerialException (const SerialException& other) : e_what_(other.e_what_) {}
  virtual ~SerialException() throw() {}
  virtual const char* what () const throw () {
    return e_what_.c_str();
  }
};

class IOException : public std::exception
{
  // Disable copy constructors
  IOException& operator=(const IOException&);
  std::string file_;
  int line_;
  std::string e_what_;
  int errno_;
public:
  explicit IOException (std::string file, int line, int errnum)
    : file_(file), line_(line), errno_(errnum) {
      std::stringstream ss;
#if defined(_WIN32) && !defined(__MINGW32__)
      char error_str [1024];
      strerror_s(error_str, 1024, errnum);
#else
      char * error_str = strerror(errnum);
#endif
      ss << "IO Exception (" << errno_ << "): " << error_str;
      ss << ", file " << file_ << ", line " << line_ << ".";
      e_what_ = ss.str();
  }
  explicit IOException (std::string file, int line, const char * description)
    : file_(file), line_(line), errno_(0) {
      std::stringstream ss;
      ss << "IO Exception: " << description;
      ss << ", file " << file_ << ", line " << line_ << ".";
      e_what_ = ss.str();
  }
  virtual ~IOException() throw() {}
  IOException (const IOException& other) : line_(other.line_), e_what_(other.e_what_), errno_(other.errno_) {}

  int getErrorNumber () const { return errno_; }

  virtual const char* what () const throw () {
    return e_what_.c_str();
  }
};

class PortNotOpenedException : public std::exception
{
  // Disable copy constructors
  const PortNotOpenedException& operator=(PortNotOpenedException);
  std::string e_what_;
public:
  PortNotOpenedException (const char * description)  {
      std::stringstream ss;
      ss << "PortNotOpenedException " << description << " failed.";
      e_what_ = ss.str();
  }
  PortNotOpenedException (const PortNotOpenedException& other) : e_what_(other.e_what_) {}
  virtual ~PortNotOpenedException() throw() {}
  virtual const char* what () const throw () {
    return e_what_.c_str();
  }
};

/*!
 * Structure that describes a serial device.
 */
struct PortInfo {

  /*! Address of the serial port (this can be passed to the constructor of Serial). */
  std::string port;

  /*! Human readable description of serial device if available. */
  std::string description;

  /*! Hardware ID (e.g. VID:PID of USB serial devices) or "n/a" if not available. */
  std::string hardware_id;

};

/* Lists the serial ports available on the system
 *
 * Returns a vector of available serial ports, each represented
 * by a serial::PortInfo data structure:
 *
 * \return vector of serial::PortInfo.
 */
std::vector<PortInfo>
list_ports();

} // namespace serial

#endif