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// ORIGINAL BELOW
/*
 * File:   AsyncSerial.cpp
 * Author: Terraneo Federico
 * Distributed under the Boost Software License, Version 1.0.
 * Created on September 7, 2009, 10:46 AM
 *
 * v1.02: Fixed a bug in BufferedAsyncSerial: Using the default constructor
 * the callback was not set up and reading didn't work.
 *
 * v1.01: Fixed a bug that did not allow to reopen a closed serial port.
 *
 * v1.00: First release.
 *
 * IMPORTANT:
 * On Mac OS X boost asio's serial ports have bugs, and the usual implementation
 * of this class does not work. So a workaround class was written temporarily,
 * until asio (hopefully) will fix Mac compatibility for serial ports.
 * 
 * Please note that unlike said in the documentation on OS X until asio will
 * be fixed serial port *writes* are *not* asynchronous, but at least
 * asynchronous *read* works.
 * In addition the serial port open ignores the following options: parity,
 * character size, flow, stop bits, and defaults to 8N1 format.
 * I know it is bad but at least it's better than nothing.
 *
 */

#include <pressure_cells/AsyncSerial.h>

#include <string>
#include <algorithm>
#include <iostream>
#include <boost/bind.hpp>

using namespace std;

using namespace boost;

//
//Class AsyncSerial
//

#ifndef __APPLE__

class AsyncSerialImpl:private
   boost::noncopyable {
 public:
   AsyncSerialImpl (  ):
   io (  ),
   port ( io ),
   backgroundThread (  ),
   open ( false ),
   error ( false ) {
   }
   boost::asio::io_service
      io;                       

   boost::asio::serial_port port;   
   boost::thread backgroundThread;  
   bool open;                   

   bool error;                  

   mutable boost::mutex errorMutex; 

   std::vector < char >
      writeQueue;

   boost::shared_array < char >
      writeBuffer;              

   size_t writeBufferSize;      

   boost::mutex writeQueueMutex;    
   char
     readBuffer[AsyncSerial::readBufferSize];   

   boost::function < void ( const char *, size_t ) >
      callback;
};

AsyncSerial::AsyncSerial (  ):pimpl ( new AsyncSerialImpl )
{

}

AsyncSerial::AsyncSerial ( const std::string & devname, unsigned int baud_rate,
                           asio::serial_port_base::parity opt_parity,
                           asio::serial_port_base::character_size opt_csize,
                           asio::serial_port_base::flow_control opt_flow,
                           asio::serial_port_base::stop_bits opt_stop ):
pimpl ( new AsyncSerialImpl )
{
   open ( devname, baud_rate, opt_parity, opt_csize, opt_flow, opt_stop );
}

void








 
   AsyncSerial::open ( const std::string & devname, unsigned int baud_rate,
                       asio::serial_port_base::parity opt_parity,
                       asio::serial_port_base::character_size opt_csize,
                       asio::serial_port_base::flow_control opt_flow,
                       asio::serial_port_base::stop_bits opt_stop )
{
   if ( isOpen (  ) )
      close (  );

   setErrorStatus ( true );     //If an exception is thrown, error_ remains true
   pimpl->port.open ( devname );
   pimpl->port.set_option ( asio::serial_port_base::baud_rate ( baud_rate ) );
   pimpl->port.set_option ( opt_parity );
   pimpl->port.set_option ( opt_csize );
   pimpl->port.set_option ( opt_flow );
   pimpl->port.set_option ( opt_stop );

   //This gives some work to the io_service before it is started
   pimpl->io.post ( boost::bind ( &AsyncSerial::doRead, this ) );

   thread t ( boost::bind ( &asio::io_service::run, &pimpl->io ) );

   pimpl->backgroundThread.swap ( t );
   setErrorStatus ( false );    //If we get here, no error
   pimpl->open = true;          //Port is now open
}

bool AsyncSerial::isOpen (  ) const
{
   return pimpl->open;
}

bool AsyncSerial::errorStatus (  ) const
{
   lock_guard < mutex > l ( pimpl->errorMutex );
   return pimpl->error;
}

void
  AsyncSerial::close (  )
{
   if ( !isOpen (  ) )
      return;

   pimpl->open = false;
   pimpl->io.post ( boost::bind ( &AsyncSerial::doClose, this ) );
   pimpl->backgroundThread.join (  );
   pimpl->io.reset (  );
   if ( errorStatus (  ) )
     {
        throw ( boost::system::system_error ( boost::system::error_code (  ),
                                              "Error while closing the device" ) );
     }
}

void
  AsyncSerial::write ( const char *data, size_t size )
{
   {
      lock_guard < mutex > l ( pimpl->writeQueueMutex );
      pimpl->writeQueue.insert ( pimpl->writeQueue.end (  ), data, data + size );
   }
   pimpl->io.post ( boost::bind ( &AsyncSerial::doWrite, this ) );
}

void
  AsyncSerial::write ( const std::vector < char >&data )
{
   {
      lock_guard < mutex > l ( pimpl->writeQueueMutex );
      pimpl->writeQueue.insert ( pimpl->writeQueue.end (  ), data.begin (  ),
                                 data.end (  ) );
   }
   pimpl->io.post ( boost::bind ( &AsyncSerial::doWrite, this ) );
}

void
  AsyncSerial::writeString ( const std::string & s )
{
   {
      lock_guard < mutex > l ( pimpl->writeQueueMutex );
      pimpl->writeQueue.insert ( pimpl->writeQueue.end (  ), s.begin (  ), s.end (  ) );
   }
   pimpl->io.post ( boost::bind ( &AsyncSerial::doWrite, this ) );
}

AsyncSerial::~AsyncSerial (  )
{
   if ( isOpen (  ) )
     {
        try
        {
           close (  );
        }
        catch ( ... )
        {
           //Don't throw from a destructor
        }
     }
}

void
  AsyncSerial::doRead (  )
{
   pimpl->port.async_read_some ( asio::buffer ( pimpl->readBuffer, readBufferSize ),
                                 boost::bind ( &AsyncSerial::readEnd,
                                               this,
                                               asio::placeholders::error,
                                               asio::placeholders::bytes_transferred ) );
}

void
  AsyncSerial::readEnd ( const boost::system::error_code & error,
                          size_t bytes_transferred )
{
   if ( error )
     {
#ifdef __APPLE__
        if ( error.value (  ) == 45 )
          {
             //Bug on OS X, it might be necessary to repeat the setup
             //http://osdir.com/ml/lib.boost.asio.user/2008-08/msg00004.html
             doRead (  );
             return;
          }
#endif //__APPLE__
        //error can be true even because the serial port was closed.
        //In this case it is not a real error, so ignore
        if ( isOpen (  ) )
          {
             doClose (  );
             setErrorStatus ( true );
          }
   } else
     {
        if ( pimpl->callback )
           pimpl->callback ( pimpl->readBuffer, bytes_transferred );
        doRead (  );
     }
}

void
  AsyncSerial::doWrite (  )
{
   //If a write operation is already in progress, do nothing
   if ( pimpl->writeBuffer == 0 )
     {
        lock_guard < mutex > l ( pimpl->writeQueueMutex );
        pimpl->writeBufferSize = pimpl->writeQueue.size (  );
        pimpl->writeBuffer.reset ( new char[pimpl->writeQueue.size (  )] );

        copy ( pimpl->writeQueue.begin (  ), pimpl->writeQueue.end (  ),
               pimpl->writeBuffer.get (  ) );
        pimpl->writeQueue.clear (  );
        async_write ( pimpl->port, asio::buffer ( pimpl->writeBuffer.get (  ),
                                                  pimpl->writeBufferSize ),
                      boost::bind ( &AsyncSerial::writeEnd, this,
                                    asio::placeholders::error ) );
     }
}

void
  AsyncSerial::writeEnd ( const boost::system::error_code & error )
{
   if ( !error )
     {
        lock_guard < mutex > l ( pimpl->writeQueueMutex );
        if ( pimpl->writeQueue.empty (  ) )
          {
             pimpl->writeBuffer.reset (  );
             pimpl->writeBufferSize = 0;

             return;
          }
        pimpl->writeBufferSize = pimpl->writeQueue.size (  );
        pimpl->writeBuffer.reset ( new char[pimpl->writeQueue.size (  )] );
        copy ( pimpl->writeQueue.begin (  ), pimpl->writeQueue.end (  ),
               pimpl->writeBuffer.get (  ) );
        pimpl->writeQueue.clear (  );
        async_write ( pimpl->port, asio::buffer ( pimpl->writeBuffer.get (  ),
                                                  pimpl->writeBufferSize ),
                      boost::bind ( &AsyncSerial::writeEnd, this,
                                    asio::placeholders::error ) );
   } else
     {
        setErrorStatus ( true );
        doClose (  );
     }
}

void
  AsyncSerial::doClose (  )
{
   boost::system::error_code ec;
   pimpl->port.cancel ( ec );
   if ( ec )
      setErrorStatus ( true );
   pimpl->port.close ( ec );
   if ( ec )
      setErrorStatus ( true );
}

void
  AsyncSerial::setErrorStatus ( bool e )
{
   lock_guard < mutex > l ( pimpl->errorMutex );
   pimpl->error = e;
}

void
   AsyncSerial::setReadCallback ( const boost::function < void ( const char *, size_t ) >
                                  &callback )
{
   pimpl->callback = callback;
}

void
  AsyncSerial::clearReadCallback (  )
{
   pimpl->callback.clear (  );
}

#else //__APPLE__

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <termios.h>
#include <unistd.h>

class AsyncSerialImpl:private
   boost::noncopyable {
 public:
   AsyncSerialImpl (  ):
   backgroundThread (  ),
   open ( false ),
   error ( false ) {
   }
   boost::thread
      backgroundThread;         

   bool open;                   

   bool error;                  

   mutable boost::mutex errorMutex; 

   int
     fd;                        

   char
     readBuffer[AsyncSerial::readBufferSize];   

   boost::function < void ( const char *, size_t ) >
      callback;
};

AsyncSerial::AsyncSerial (  ):pimpl ( new AsyncSerialImpl )
{

}

AsyncSerial::AsyncSerial ( const std::string & devname, unsigned int baud_rate,
                           asio::serial_port_base::parity opt_parity,
                           asio::serial_port_base::character_size opt_csize,
                           asio::serial_port_base::flow_control opt_flow,
                           asio::serial_port_base::stop_bits opt_stop ):
pimpl ( new AsyncSerialImpl )
{
   open ( devname, baud_rate, opt_parity, opt_csize, opt_flow, opt_stop );
}

void
  AsyncSerial::open ( const std::string & devname, unsigned int baud_rate,
                       asio::serial_port_base::parity opt_parity,
                       asio::serial_port_base::character_size opt_csize,
                       asio::serial_port_base::flow_control opt_flow,
                       asio::serial_port_base::stop_bits opt_stop )
{
   if ( isOpen (  ) )
      close (  );

   setErrorStatus ( true );     //If an exception is thrown, error remains true

   struct termios new_attributes;

   speed_t speed;

   int status;

   // Open port
   pimpl->fd =::open ( devname.c_str (  ), O_RDWR | O_NOCTTY | O_NONBLOCK );
   if ( pimpl->fd < 0 )
      throw ( boost::system::system_error ( boost::system::error_code (  ),
                                            "Failed to open port" ) );

   // Set Port parameters.
   status = tcgetattr ( pimpl->fd, &new_attributes );
   if ( status < 0 || !isatty ( pimpl->fd ) )
     {
        ::close ( pimpl->fd );
        throw ( boost::system::system_error ( boost::system::error_code (  ),
                                              "Device is not a tty" ) );
     }
   new_attributes.c_iflag = IGNBRK;
   new_attributes.c_oflag = 0;
   new_attributes.c_lflag = 0;
   new_attributes.c_cflag = ( CS8 | CREAD | CLOCAL );   //8 data bit,Enable receiver,Ignore modem
   /* In non canonical mode (Ctrl-C and other disabled, no echo,...) VMIN and VTIME work this way:
      if the function read() has'nt read at least VMIN chars it waits until has read at least VMIN
      chars (even if VTIME timeout expires); once it has read at least vmin chars, if subsequent
      chars do not arrive before VTIME expires, it returns error; if a char arrives, it resets the
      timeout, so the internal timer will again start from zero (for the nex char,if any) */
   new_attributes.c_cc[VMIN] = 1;   // Minimum number of characters to read before returning error
   new_attributes.c_cc[VTIME] = 1;  // Set timeouts in tenths of second

   // Set baud rate
   switch ( baud_rate )
     {
     case 50:
        speed = B50;
        break;
     case 75:
        speed = B75;
        break;
     case 110:
        speed = B110;
        break;
     case 134:
        speed = B134;
        break;
     case 150:
        speed = B150;
        break;
     case 200:
        speed = B200;
        break;
     case 300:
        speed = B300;
        break;
     case 600:
        speed = B600;
        break;
     case 1200:
        speed = B1200;
        break;
     case 1800:
        speed = B1800;
        break;
     case 2400:
        speed = B2400;
        break;
     case 4800:
        speed = B4800;
        break;
     case 9600:
        speed = B9600;
        break;
     case 19200:
        speed = B19200;
        break;
     case 38400:
        speed = B38400;
        break;
     case 57600:
        speed = B57600;
        break;
     case 115200:
        speed = B115200;
        break;
     case 230400:
        speed = B230400;
        break;
     default:
        {
           ::close ( pimpl->fd );
           throw ( boost::system::system_error ( boost::system::error_code (  ),
                                                 "Unsupported baud rate" ) );
        }
     }

   cfsetospeed ( &new_attributes, speed );
   cfsetispeed ( &new_attributes, speed );

   //Make changes effective
   status = tcsetattr ( pimpl->fd, TCSANOW, &new_attributes );
   if ( status < 0 )
     {
        ::close ( pimpl->fd );
        throw ( boost::system::system_error ( boost::system::error_code (  ),
                                              "Can't set port attributes" ) );
     }
   //These 3 lines clear the O_NONBLOCK flag
   status = fcntl ( pimpl->fd, F_GETFL, 0 );
   if ( status != -1 )
      fcntl ( pimpl->fd, F_SETFL, status & ~O_NONBLOCK );

   setErrorStatus ( false );    //If we get here, no error
   pimpl->open = true;          //Port is now open

   thread t ( bind ( &AsyncSerial::doRead, this ) );

   pimpl->backgroundThread.swap ( t );
}

     bool AsyncSerial::isOpen (  ) const {
        return
           pimpl->
           open;
     }
     bool
     AsyncSerial::errorStatus (  )  const {
        lock_guard <
           mutex >
        l ( pimpl->errorMutex );
        return
           pimpl->
           error;
     }
     void
     AsyncSerial::close (  )
{
   if ( !isOpen (  ) )
      return;

   pimpl->open = false;

   ::close ( pimpl->fd );       //The thread waiting on I/O should return

   pimpl->backgroundThread.join (  );
   if ( errorStatus (  ) )
     {
        throw ( boost::system::system_error ( boost::system::error_code (  ),
                                              "Error while closing the device" ) );
     }
}

void
  AsyncSerial::write ( const char *data, size_t size )
{
   if ( ::write ( pimpl->fd, data, size ) != size )
      setErrorStatus ( true );
}

void
  AsyncSerial::write ( const std::vector < char >&data )
{
   if ( ::write ( pimpl->fd, &data[0], data.size (  ) ) != data.size (  ) )
      setErrorStatus ( true );
}

void
  AsyncSerial::writeString ( const std::string & s )
{
   if ( ::write ( pimpl->fd, &s[0], s.size (  ) ) != s.size (  ) )
      setErrorStatus ( true );
}

AsyncSerial::~AsyncSerial (  )
{
   if ( isOpen (  ) )
     {
        try
        {
           close (  );
        }
        catch ( ... )
        {
           //Don't throw from a destructor
        }
     }
}

void
  AsyncSerial::doRead (  )
{
   //Read loop in spawned thread
   for ( ;; )
     {
        int
          received =::read ( pimpl->fd, pimpl->readBuffer, readBufferSize );

        if ( received < 0 )
          {
             if ( isOpen (  ) == false )
                return;         //Thread interrupted because port closed
             else
               {
                  setErrorStatus ( true );
                  continue;
               }
          }
        if ( pimpl->callback )
           pimpl->callback ( pimpl->readBuffer, received );
     }
}

void
AsyncSerial::readEnd ( const boost::system::error_code & error,
                          size_t bytes_transferred )
{
   //Not used
}

void
  AsyncSerial::doWrite (  )
{
   //Not used
}

void
  AsyncSerial::writeEnd ( const boost::system::error_code & error )
{
   //Not used
}

void
  AsyncSerial::doClose (  )
{
   //Not used
}

void
  AsyncSerial::setErrorStatus ( bool e )
{
   lock_guard < mutex > l ( pimpl->errorMutex );
   pimpl->error = e;
}

void
  AsyncSerial::setReadCallback ( const
                                 function < void ( const char *, size_t ) > &callback )
{
   pimpl->callback = callback;
}

void
  AsyncSerial::clearReadCallback (  )
{
   pimpl->callback.clear (  );
}

#endif //__APPLE__

//
//Class CallbackAsyncSerial
//

CallbackAsyncSerial::CallbackAsyncSerial (  ):AsyncSerial (  )
{

}

CallbackAsyncSerial::CallbackAsyncSerial ( const std::string & devname,
                                           unsigned int baud_rate,
                                           asio::serial_port_base::parity opt_parity,
                                           asio::
                                           serial_port_base::character_size opt_csize,
                                           asio::serial_port_base::flow_control opt_flow,
                                           asio::serial_port_base::stop_bits opt_stop ):
AsyncSerial ( devname, baud_rate, opt_parity, opt_csize, opt_flow, opt_stop )
{

}

void
  CallbackAsyncSerial::setCallback ( const
                                     boost::function < void ( const char *,
                                                              size_t ) > &callback )
{
   setReadCallback ( callback );
}

void
  CallbackAsyncSerial::clearCallback (  )
{
   clearReadCallback (  );
}

CallbackAsyncSerial::~CallbackAsyncSerial (  )
{
   clearReadCallback (  );
}

---

pressure_cells
Author(s): Emilio Estrelinha
autogenerated on Wed Jul 23 04:34:41 2014