src/lib/platform/windows/serialport.cpp

   1 /*
   2  * This file is part of the libCEC(R) library.
   3  *
   4  * libCEC(R) is Copyright (C) 2011-2012 Pulse-Eight Limited.  All rights reserved.
   5  * libCEC(R) is an original work, containing original code.
   6  *
   7  * libCEC(R) is a trademark of Pulse-Eight Limited.
   8  *
   9  * This program is dual-licensed; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  22  *
  23  *
  24  * Alternatively, you can license this library under a commercial license,
  25  * please contact Pulse-Eight Licensing for more information.
  26  *
  27  * For more information contact:
  28  * Pulse-Eight Licensing       <license@pulse-eight.com>
  29  *     http://www.pulse-eight.com/
  30  *     http://www.pulse-eight.net/
  31  */
  32
  33 #include "../sockets/serialport.h"
  34 #include "../util/baudrate.h"
  35 #include "../util/timeutils.h"
  36
  37 using namespace std;
  38 using namespace PLATFORM;
  39
  40 void CSerialPort::FormatWindowsError(int iErrorCode, CStdString &strMessage)
  41 {
  42   if (iErrorCode != ERROR_SUCCESS)
  43   {
  44     char strAddMessage[1024];
  45     FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, NULL, iErrorCode, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), strAddMessage, 1024, NULL);
  46     strMessage.append(": ");
  47     strMessage.append(strAddMessage);
  48   }
  49 }
  50
  51 CSerialPort::CSerialPort(void) :
  52   m_handle(INVALID_HANDLE_VALUE),
  53   m_bIsOpen(false),
  54   m_iBaudrate(0),
  55   m_iDatabits(0),
  56   m_iStopbits(0),
  57   m_iParity(0)
  58 {
  59 }
  60
  61 bool CSerialPort::Open(string name, uint32_t baudrate, uint8_t databits, uint8_t stopbits, uint8_t parity)
  62 {
  63   CStdString strComPath = "\\\\.\\" + name;
  64   CLockObject lock(m_mutex);
  65   m_handle = CreateFile(strComPath.c_str(), GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0);
  66   if (m_handle == INVALID_HANDLE_VALUE)
  67   {
  68     m_strError = "Unable to open COM port";
  69     FormatWindowsError(GetLastError(), m_strError);
  70     return false;
  71   }
  72
  73   COMMCONFIG commConfig = {0};
  74   DWORD dwSize = sizeof(commConfig);
  75   commConfig.dwSize = dwSize;
  76   if (GetDefaultCommConfig(strComPath.c_str(), &commConfig,&dwSize))
  77   {
  78     if (!SetCommConfig(m_handle, &commConfig,dwSize))
  79     {
  80       m_strError = "unable to set default config";
  81       FormatWindowsError(GetLastError(), m_strError);
  82     }
  83   }
  84   else
  85   {
  86     m_strError = "unable to get default config";
  87     FormatWindowsError(GetLastError(), m_strError);
  88   }
  89
  90   if (!SetupComm(m_handle, 64, 64))
  91   {
  92     m_strError = "unable to set up the com port";
  93     FormatWindowsError(GetLastError(), m_strError);
  94   }
  95
  96   m_iDatabits = databits;
  97   m_iStopbits = stopbits;
  98   m_iParity   = parity;
  99   if (!SetBaudRate(baudrate))
 100   {
 101     m_strError = "unable to set baud rate";
 102     FormatWindowsError(GetLastError(), m_strError);
 103     Close();
 104     return false;
 105   }
 106
 107   if (!SetTimeouts(false))
 108   {
 109     m_strError = "unable to set timeouts";
 110     FormatWindowsError(GetLastError(), m_strError);
 111     Close();
 112     return false;
 113   }
 114
 115   m_bIsOpen = true;
 116   return m_bIsOpen;
 117 }
 118
 119 bool CSerialPort::SetTimeouts(bool bBlocking)
 120 {
 121   if (m_handle == INVALID_HANDLE_VALUE)
 122           return false;
 123
 124   COMMTIMEOUTS cto;
 125   if (!GetCommTimeouts(m_handle, &cto))
 126   {
 127     m_strError = "GetCommTimeouts failed";
 128     FormatWindowsError(GetLastError(), m_strError);
 129     return false;
 130   }
 131
 132   if (bBlocking)
 133   {
 134     cto.ReadIntervalTimeout         = 0;
 135     cto.ReadTotalTimeoutConstant    = 0;
 136     cto.ReadTotalTimeoutMultiplier  = 0;
 137   }
 138   else
 139   {
 140     cto.ReadIntervalTimeout         = MAXDWORD;
 141     cto.ReadTotalTimeoutConstant    = 0;
 142     cto.ReadTotalTimeoutMultiplier  = 0;
 143   }
 144
 145   if (!SetCommTimeouts(m_handle, &cto))
 146   {
 147     m_strError = "SetCommTimeouts failed";
 148     FormatWindowsError(GetLastError(), m_strError);
 149     return false;
 150   }
 151
 152   return true;
 153 }
 154
 155 void CSerialPort::Close(void)
 156 {
 157   CLockObject lock(m_mutex);
 158   if (m_bIsOpen)
 159   {
 160     CloseHandle(m_handle);
 161     m_bIsOpen = false;
 162   }
 163 }
 164
 165 int64_t CSerialPort::Write(uint8_t* data, uint32_t len)
 166 {
 167   CLockObject lock(m_mutex);
 168   DWORD iBytesWritten = 0;
 169   if (!m_bIsOpen)
 170     return -1;
 171
 172   if (!WriteFile(m_handle, data, len, &iBytesWritten, NULL))
 173   {
 174     m_strError = "Error while writing to COM port";
 175     FormatWindowsError(GetLastError(), m_strError);
 176     return -1;
 177   }
 178
 179   return (int64_t)iBytesWritten;
 180 }
 181
 182 int32_t CSerialPort::Read(uint8_t* data, uint32_t len, uint64_t iTimeoutMs /* = 0 */)
 183 {
 184   CLockObject lock(m_mutex);
 185   int32_t iReturn(-1);
 186   DWORD iBytesRead = 0;
 187   if (m_handle == 0)
 188   {
 189     m_strError = "Error while reading from COM port: invalid handle";
 190     return iReturn;
 191   }
 192
 193   if(!ReadFile(m_handle, data, len, &iBytesRead, NULL) != 0)
 194   {
 195     m_strError = "unable to read from device";
 196     FormatWindowsError(GetLastError(), m_strError);
 197     iReturn = -1;
 198   }
 199   else
 200   {
 201     iReturn = (int32_t) iBytesRead;
 202   }
 203
 204   return iReturn;
 205 }
 206
 207 bool CSerialPort::SetBaudRate(uint32_t baudrate)
 208 {
 209   int32_t rate = IntToBaudrate(baudrate);
 210   if (rate < 0)
 211     m_iBaudrate = baudrate > 0 ? baudrate : 0;
 212   else
 213     m_iBaudrate = rate;
 214
 215   DCB dcb;
 216   memset(&dcb,0,sizeof(dcb));
 217   dcb.DCBlength = sizeof(dcb);
 218   dcb.BaudRate      = IntToBaudrate(m_iBaudrate);
 219   dcb.fBinary       = true;
 220   dcb.fDtrControl   = DTR_CONTROL_DISABLE;
 221   dcb.fRtsControl   = RTS_CONTROL_DISABLE;
 222   dcb.fOutxCtsFlow  = false;
 223   dcb.fOutxDsrFlow  = false;
 224   dcb.fOutX         = false;
 225         dcb.fInX          = false;
 226   dcb.fAbortOnError = true;
 227
 228   if (m_iParity == PAR_NONE)
 229     dcb.Parity = NOPARITY;
 230   else if (m_iParity == PAR_EVEN)
 231     dcb.Parity = EVENPARITY;
 232   else
 233     dcb.Parity = ODDPARITY;
 234
 235   if (m_iStopbits == 2)
 236     dcb.StopBits = TWOSTOPBITS;
 237   else
 238     dcb.StopBits = ONESTOPBIT;
 239
 240   dcb.ByteSize = m_iDatabits;
 241
 242   if(!SetCommState(m_handle,&dcb))
 243   {
 244     m_strError = "SetCommState failed";
 245     FormatWindowsError(GetLastError(), m_strError);
 246     return false;
 247   }
 248
 249   return true;
 250 }
 251
 252 bool CSerialPort::IsOpen(void)
 253 {
 254   CLockObject lock(m_mutex);
 255   return m_bIsOpen;
 256 }