ArBasePacket.cpp

/*
MobileRobots Advanced Robotics Interface for Applications (ARIA)
Copyright (C) 2004, 2005 ActivMedia Robotics LLC
Copyright (C) 2006, 2007 MobileRobots Inc.

     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
     the Free Software Foundation; either version 2 of the License, or
     (at your option) any later version.

     This program is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     GNU General Public License for more details.

     You should have received a copy of the GNU General Public License
     along with this program; if not, write to the Free Software
     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

If you wish to redistribute ARIA under different terms, contact 
MobileRobots for information about a commercial version of ARIA at 
robots@mobilerobots.com or 
MobileRobots Inc, 19 Columbia Drive, Amherst, NH 03031; 800-639-9481
*/

#include "ArExport.h"
#include "ariaOSDef.h"
#include "ArBasePacket.h"
#include "ArLog.h"

#include <stdio.h>

AREXPORT ArBasePacket::ArBasePacket(ArTypes::UByte2 bufferSize, 
                                    ArTypes::UByte2 headerLength,
                                    char * buf,
                                    ArTypes::UByte2 footerLength) 
{
  if (buf == NULL && bufferSize > 0) 
  {
    myOwnMyBuf = true;
    myBuf = new char[bufferSize];
  } 
  else 
  {
    myOwnMyBuf = false;
    myBuf = buf;
  }
  myHeaderLength = headerLength;
  myFooterLength = footerLength;
  myReadLength = myHeaderLength;
  myMaxLength = bufferSize;
  myLength = myHeaderLength;
  myIsValid = true;
}

AREXPORT ArBasePacket::~ArBasePacket()
{
  if (myOwnMyBuf && myBuf != NULL)
    delete[] myBuf;
}


AREXPORT void ArBasePacket::setBuf(char *buf, ArTypes::UByte2 bufferSize)
{
  if (myOwnMyBuf) 
  {
    delete[] myBuf;
    myOwnMyBuf = false;
  } 
  myBuf = buf;
  myMaxLength = bufferSize;
}

AREXPORT void ArBasePacket::setMaxLength(ArTypes::UByte2 bufferSize)
{
  if (myMaxLength >= bufferSize)
    return;
  if (myOwnMyBuf) 
  {
    delete[] myBuf;
    myOwnMyBuf = false;
  } 
  myBuf = new char[bufferSize];
  myMaxLength = bufferSize;
  myOwnMyBuf = true;
}

AREXPORT bool ArBasePacket::setLength(ArTypes::UByte2 length)
{
  if (myOwnMyBuf && length > myMaxLength)
    return false;

  myLength = length;
  return true;
}

AREXPORT void ArBasePacket::setReadLength(ArTypes::UByte2 readLength)
{
  myReadLength = readLength;
}

AREXPORT bool ArBasePacket::setHeaderLength(ArTypes::UByte2 length)
{
  if (myOwnMyBuf && length > myMaxLength)
    return false;

  myHeaderLength = length;
  return true;
}

AREXPORT void ArBasePacket::resetRead(void)
{
  myReadLength = myHeaderLength;
  resetValid();
}

AREXPORT void ArBasePacket::empty(void)
{
  myLength = myHeaderLength;
  resetValid();
}

AREXPORT bool ArBasePacket::isNextGood(int bytes)
{
  if (bytes <= 0)
    return false;

  // make sure it comes in before the header
  if (myReadLength + bytes <= myLength - myFooterLength)
    return true;

  myIsValid = false;

  return false;
}


AREXPORT bool ArBasePacket::hasWriteCapacity(int bytes)
{
  if (bytes < 0) {
    ArLog::log(ArLog::Normal, "ArBasePacket::hasWriteCapacity(%d) cannot write negative amount",
               bytes);
    return false;
  }

  // Make sure there's enough room in the packet 
  if ((myLength + bytes) <= myMaxLength) {
     return true;
  }

  myIsValid = false;

  return false;

} // end method hasWriteCapacity


AREXPORT bool ArBasePacket::isValid(void)
{
  return myIsValid;

} // end method isValid

AREXPORT void ArBasePacket::resetValid()
{
  myIsValid = true;
}

AREXPORT const char *ArBasePacket::getBuf(void)
{
  return myBuf;
}

AREXPORT void ArBasePacket::byteToBuf(ArTypes::Byte val)
{
  if (!hasWriteCapacity(1)) {
    return;
  }

  memcpy(myBuf+myLength, &val, 1);
  myLength += 1;
}

AREXPORT void ArBasePacket::byte2ToBuf(ArTypes::Byte2 val)
{
  if (!hasWriteCapacity(2)) {
    return;
  }

  unsigned char c;
  c = (val >> 8) & 0xff;
  memcpy(myBuf+myLength+1, &c, 1);
  c = val & 0xff;
  memcpy(myBuf+myLength, &c, 1);
  myLength += 2;
}

AREXPORT void ArBasePacket::byte4ToBuf(ArTypes::Byte4 val)
{
  if (!hasWriteCapacity(4)) {
    return;
  }

  unsigned char c;
  c = (val >> 24) & 0xff;
  memcpy(myBuf+myLength+3, &c, 1);
  c = (val >> 16) & 0xff;
  memcpy(myBuf+myLength+2, &c, 1);
  c = (val >> 8) & 0xff;
  memcpy(myBuf+myLength+1, &c, 1);
  c = val & 0xff;
  memcpy(myBuf+myLength, &c, 1);
  myLength += 4;

}

AREXPORT void ArBasePacket::uByteToBuf(ArTypes::UByte val)
{
  if (!hasWriteCapacity(1)) {
    return;
  }
  memcpy(myBuf+myLength, &val, 1);
  myLength += 1;
}

AREXPORT void ArBasePacket::uByte2ToBuf(ArTypes::UByte2 val)
{
  if (!hasWriteCapacity(2)) {
    return;
  }
  unsigned char c;
  c = (val >> 8) & 0xff;
  memcpy(myBuf+myLength+1, &c, 1);
  c = val & 0xff;
  memcpy(myBuf+myLength, &c, 1);
  myLength += 2;
}

AREXPORT void ArBasePacket::uByte4ToBuf(ArTypes::UByte4 val)
{
  if (!hasWriteCapacity(4)) {
    return;
  }
  memcpy(myBuf+myLength, &val, 4);
  myLength += 4;
}

AREXPORT void ArBasePacket::strToBuf(const char *str)
{
  if (str == NULL) {
    str = "";
  }
  ArTypes::UByte2 tempLen = strlen(str) + 1;

  if (!hasWriteCapacity(tempLen)) {
    return;
  }

  memcpy(myBuf+myLength, str, tempLen);
  myLength += tempLen;
}

AREXPORT void ArBasePacket::strNToBuf(const char *str, int length)
{
  // Do not perform bounds checking because it breaks existing code.

  //byte4ToBuf(length);
  memcpy(myBuf+myLength, str, length);
  myLength+=length;

}


AREXPORT void ArBasePacket::strToBufPadded(const char *str, int length)
{
  if (str == NULL) {
    str = "";
  }
  ArTypes::UByte2 tempLen = strlen(str);

  if (!hasWriteCapacity(length)) {
    return;
  }

  if (tempLen >= length) {
    memcpy(myBuf + myLength, str, length);
    myLength += length;
  }
  else // string is smaller than given length
  {
    memcpy(myBuf + myLength, str, tempLen);
    myLength += tempLen;
    memset(myBuf + myLength, 0, length - tempLen);
    myLength += length - tempLen;
  }
}


AREXPORT void ArBasePacket::dataToBuf(const char *data, int length)
{
  if (data == NULL) {
    ArLog::log(ArLog::Normal, "ArBasePacket::dataToBuf(NULL, %d) cannot add from null address",
               length);
    return;
  }

  if (!hasWriteCapacity(length)) {
    return;
  }

  memcpy(myBuf+myLength, data, length);
  myLength+=length;

}

AREXPORT void ArBasePacket::dataToBuf(const unsigned char *data, int length)
{
  if (data == NULL) {
    ArLog::log(ArLog::Normal, "ArBasePacket::dataToBuf(NULL, %d) cannot add from null address",
               length);
    return;
  }

  if (!hasWriteCapacity(length)) {
    return;
  }

  memcpy(myBuf+myLength, data, length);
  myLength+=length;

}


AREXPORT ArTypes::Byte ArBasePacket::bufToByte(void)
{
  ArTypes::Byte ret=0;

  if (isNextGood(1))
  {
    memcpy(&ret, myBuf+myReadLength, 1);
    myReadLength+=1;
  }

  return(ret);
}

AREXPORT ArTypes::Byte2 ArBasePacket::bufToByte2(void)
{
  ArTypes::Byte2 ret=0;
  unsigned char c1, c2;

  if (isNextGood(2))
  {
    memcpy(&c1, myBuf+myReadLength, 1);
    memcpy(&c2, myBuf+myReadLength+1, 1);
    ret = (c1 & 0xff) | (c2 << 8);
    myReadLength+=2;
  }

  return ret;
}

AREXPORT ArTypes::Byte4 ArBasePacket::bufToByte4(void)
{
  ArTypes::Byte4 ret=0;
  unsigned char c1, c2, c3, c4;

  if (isNextGood(4))
  {
    memcpy(&c1, myBuf+myReadLength, 1);
    memcpy(&c2, myBuf+myReadLength+1, 1);
    memcpy(&c3, myBuf+myReadLength+2, 1);
    memcpy(&c4, myBuf+myReadLength+3, 1);
    ret = (c1 & 0xff) | (c2 << 8) | (c3 << 16) | (c4 << 24);
    myReadLength+=4;
  }

  return ret;
}

AREXPORT ArTypes::UByte ArBasePacket::bufToUByte(void)
{
  ArTypes::UByte ret=0;

  if (isNextGood(1))
  {
    memcpy(&ret, myBuf+myReadLength, 1);
    myReadLength+=1;
  }

  return(ret);
}

AREXPORT ArTypes::UByte2 ArBasePacket::bufToUByte2(void)
{
  ArTypes::UByte2 ret=0;
  unsigned char c1, c2;

  if (isNextGood(2))
  {
    memcpy(&c1, myBuf+myReadLength, 1);
    memcpy(&c2, myBuf+myReadLength+1, 1);
    ret = (c1 & 0xff) | (c2 << 8);
    myReadLength+=2;
  }

  return ret;
}

AREXPORT ArTypes::UByte4 ArBasePacket::bufToUByte4(void)
{
  ArTypes::Byte4 ret=0;
  unsigned char c1, c2, c3, c4;

  if (isNextGood(4))
  {
    memcpy(&c1, myBuf+myReadLength, 1);
    memcpy(&c2, myBuf+myReadLength+1, 1);
    memcpy(&c3, myBuf+myReadLength+2, 1);
    memcpy(&c4, myBuf+myReadLength+3, 1);
    ret = (c1 & 0xff) | (c2 << 8) | (c3 << 16) | (c4 << 24);
    myReadLength+=4;
  }

  return ret;
}

AREXPORT void ArBasePacket::bufToStr(char *buf, int len)
{
   if (buf == NULL) {
    ArLog::log(ArLog::Normal, "ArBasePacket::bufToStr(NULL, %d) cannot write to null address",
               len);
    return;
  }

  int i;

  buf[0] = '\0';
  // see if we can read
  if (isNextGood(1))
  {
    // while we can read copy over those bytes
    for (i = 0; 
         isNextGood(1) && i < (len - 1) && myBuf[myReadLength] != '\0';
         ++myReadLength, ++i) {
      buf[i] = myBuf[myReadLength];
    }
    // if we stopped because of a null then copy that one too
    if (myBuf[myReadLength] == '\0')
    {
      buf[i] = myBuf[myReadLength];
      myReadLength++;
    }
    else if (i >= (len - 1)) { 

      // Otherwise, if we stopped reading because the output buffer was full,
      // then attempt to flush the rest of the string from the packet

      // This is a bit redundant with the code below, but wanted to log the  
      // string for debugging
      myBuf[len - 1] = '\0';

      ArLog::log(ArLog::Normal, "ArBasePacket::bufToStr(buf, %d) output buf is not large enough for packet string %s",
                 len, myBuf);

      while (isNextGood(1) && (myBuf[myReadLength] != '\0')) {
        myReadLength++;
      }
      if (myBuf[myReadLength] == '\0') {
        myReadLength++;
      }
    } // end else if output buffer filled before null-terminator
  } // end if something to read

  // Make absolutely sure that the string is null-terminated...
  buf[len - 1] = '\0';

}

AREXPORT void ArBasePacket::bufToData(char *data, int length)
{
  if (data == NULL) {
    ArLog::log(ArLog::Normal, "ArBasePacket::bufToData(NULL, %d) cannot write to null address",
               length);
    return;
  }
  if (isNextGood(length))
  {
    memcpy(data, myBuf+myReadLength, length);
    myReadLength += length;
  }
}


AREXPORT void ArBasePacket::bufToData(unsigned char *data, int length)
{
  if (data == NULL) {
    ArLog::log(ArLog::Normal, "ArBasePacket::bufToData(NULL, %d) cannot write to null address",
               length);
    return;
  }
  if (isNextGood(length))
  {
    memcpy(data, myBuf+myReadLength, length);
    myReadLength += length;
  }
}


AREXPORT void ArBasePacket::duplicatePacket(ArBasePacket *packet)
{
  myLength = packet->getLength();
  myReadLength = packet->getReadLength();
  memcpy(myBuf, packet->getBuf(), myLength);
}

AREXPORT void ArBasePacket::log(void)
{
  int i;
  ArLog::log(ArLog::Terse, "Packet: (length = %i)", myLength);
  for (i = 0; i < myLength; i++)
    ArLog::log(ArLog::Terse, "  [%03i] % 5d\t0x%x\t%s", i,(unsigned char) myBuf[i],
        (unsigned char) myBuf[i], 
        i == 0 ? "[header0]" :
          i == 1 ? "[header1]" :
            i == 2 ? "[packet data length]" :
              i == 3 ? "[packet id]" :
                i == (myLength - 2) ? "[first checksum byte]" :
                  i == (myLength - 1) ? "[second checksum byte]" :
                    ""
    );
  ArLog::log(ArLog::Terse, "\n");
}

AREXPORT void ArBasePacket::printHex(void)
{
  int i;
  ArLog::log(ArLog::Terse, "Packet: (length = %i)", myLength);
  for (i = 0; i < myLength; i++)
    ArLog::log(ArLog::Terse, "  [%i] 0x%x ", i,(unsigned char) myBuf[i]);
  ArLog::log(ArLog::Terse, "\n");
}

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