checker_host/interface/codec_ym.cpp

#include "codec.h"
#include "base/crc.h"
#include "interface/codec_ym.h"

// 重载接收字节函数
bool CodecYm::recvByte(int byte)
{
  bool ack = false;
  if (fullFrame == true)
  {
    return fullFrame;
  }
  data.append(uint8_t(byte));
  switch (data.size())
  {
  case 2:
    if (uint8_t(data[0]) == 0x59u && uint8_t(data[1]) == 0x6du)
    {
      is_big_data = false;
      num_to_read = 4; // 帧头+2byte负载长度
    }
    else
    {
      data.remove(0, 1);
      num_to_read = 0;
    }
    break;
  case 4:
  {
    int len = data[2] | (data[3] << 8);
    if (len < 65535)
    {
      is_big_data = false;
      num_to_read += len + 2; // 负载+2byte校验
      qDebug("normal data. len=%d", len);
    }
    else
    {
      is_big_data = true;
      num_to_read = 11; // 扩展数据长度
      qDebug("big data.");
    }
  }
  break;
  case 11:
  {
    if (is_big_data == true)
    {
      int len = data[7] | (data[8] << 8) | (data[9] << 16) | (data[10] << 24);
      num_to_read = 4 + len + 2; // 负载+2byte校验
      qDebug("big data. len=%d", len);
    }
  }
  default:
    break;
  }
  // 此时一帧数据已完成
  if (num_to_read > 0 && num_to_read == data.size())
  {
    ack = true;
    num_to_read = 0;
  }

  fullFrame = ack;
  return fullFrame;
}
// 重载解码函数
myarray CodecYm::decode(int &srcAddr, int &dstAddr, int &cmd, myarray data)
{
  Q_UNUSED(srcAddr);
  Q_UNUSED(dstAddr);
  myarray r;
  if (packCheck(data) >0)
  {
    qDebug("offset=%d",offset);
    cmd = this->cmd;
    if (is_big_data == false)
      r = data.mid(offset+7, len - 3);
    else
      r = data.mid(offset+11, len - 7);
  }
  return r;
}
int CodecYm::packCheck(myarray data)
{
  int ack = 0;
  offset=0;
  failed=false;
  while(data.size()>=2){
    if ((uint8_t(data[0]) != 0x59u) || (uint8_t(data[1]) != 0x6du))
    {
      // 帧头不对
      // qWarning("frame head not 0x59 0x6d");
      // return ack;
      data.remove(0,1);
      offset++;
    }else{
      break;
    }
  }
  if (data.size() < 9)
  {
    // 主机一帧数据至少9字节
    // qWarning("recv data len too less");
    return ack;
  }

  len = (data[2] | (data[3] << 8));
  if (len == 65535)
  {
    // 重新设置数据长度
    len = data[7] | (data[8] << 8) | (data[9] << 16) | (data[10] << 24);
    is_big_data = true;
  }
  else
  {
    is_big_data = false;
  }
  if (len + 6 > data.size())
  {
    // 如果长度不相等则产生了数据丢失
    // qWarning("recv data have lossed");
    return ack;
  }
  uint8_t chk_a = 0, chk_b = 0;
  uint8_t rchk_a=uint8_t(data[data.size() - 2]),rchk_b=uint8_t(data[data.size() - 1]);
  crc::crc16((uint8_t *)data.data(), 2, len + 4, &chk_a, &chk_b);
  if (chk_a != rchk_a || chk_b != rchk_b)
  {
    // crc校验不对
    if(rchk_a!=0xff||rchk_b!=0xff){
      qWarning("recv data check error:%02x,%02x %02x,%02x", chk_a, chk_b, rchk_a, rchk_b);
      failed=true;
    }else{
      qWarning("recv data check is 0xff 0xff,seen as check right.");
    }
  }
  // 保存此流水号
  cmd_no = data[5] | (data[6] << 8);
  cmd = data[4];
  // 数据负载
  return len+offset+6;
}
myarray CodecYm::encode(int srcAddr, int dstAddr, int cmd, myarray data)
{
  Q_UNUSED(srcAddr);
  Q_UNUSED(dstAddr);
  myarray t;
  uint32_t len = data.size() + 3;

  t.append(0x59u);
  t.append(0x6du);
  t.append(0x43u);
  if (len < 65535)
  {
    t.append((len) & 0xff);
    t.append((len) >> 8);
    t.append(cmd);
    t.append(cmd_no & 0xff);
    t.append(cmd_no >> 8);
  }
  else
  {
    len += 4;
    t.append(0xff);
    t.append(0xff);
    t.append(cmd);
    t.append(cmd_no & 0xff);
    t.append(cmd_no >> 8);
    t.append(len & 0xff);
    t.append((len >> 8) & 0xff);
    t.append((len >> 16) & 0xff);
    t.append((len >> 24) & 0xff);
  }
  t.append(data);
  uint8_t chk_a, chk_b;
  crc::crc16((uint8_t *)t.data(), 3, len + 5, &chk_a, &chk_b);
  t.append(chk_a);
  t.append(chk_b);
  return t;
}

Codec *codec_ym_get()
{
  static Codec *codec_ = nullptr;
  if (codec_ == nullptr)
  {
    codec_ = new CodecYm();
  }
  return codec_;
}

codec_export(codec_ym, codec_ym_get);