// Finite state machine for parsing XML tags of interest
void RSSReader::runStateMachine(char ch) {

  switch (state) {
    case INIT:
      // Make buffers empty
      memset(titleBuffer, 0, sizeof(titleBuffer));
      memset(descBuffer, 0, sizeof(descBuffer));
      memset(dateBuffer, 0, sizeof(dateBuffer));

      // Next state
      state = CHK_START;
      break;

    case CHK_START:
      if (ch == '<') {
        state = TEST_FIRST_CHAR;
      }
      break;

    case TEST_FIRST_CHAR:
      if (ch == date[0]) {
        dateIndex = 1;
        state = CHK_DATE;
      }
      else if (ch == title[0]) {
        titleIndex = 1;
        state = CHK_TITLE;
      } else if (ch == desc[0]) {
        descIndex = 1;
        state = CHK_DESC;
      } else  {
        state = CHK_START;
      }
      break;

    case CHK_DATE:
      if (ch != date[dateIndex]) {
        state = CHK_START;
        break;
      }
      dateIndex++;
      if (ch == '>') {
        dateIndex = 0;
        state = GET_DATE;
      }
      break;

    case CHK_TITLE:
      if (ch != title[titleIndex]) {
        state = CHK_START;
        break;
      }
      titleIndex++;
      if (ch == '>') {
        titleIndex = 0;
        state = GET_TITLE;
      }
      break;

    case CHK_DESC:
      if (ch != desc[descIndex]) {
        state = CHK_START;
        break;
      }
      descIndex++;
      if (ch == '>') {
        descIndex = 0;
        state = GET_DESC;
      }
      break;

    case GET_TITLE:
      if (ch != '<') {
        titleBuffer[titleIndex++] = ch;
      } else  {
        titleBuffer[titleIndex++] = '\0';
        if ((strlen(titleBuffer) != 0) && (titleCallback != NULL)) {
          titleCallback(titleBuffer);
        }
        state = CHK_START;
      }
      break;

    case GET_DESC:
      if ((ch != '<') && (ch != '&')) {
        descBuffer[descIndex++] = ch;
      } else  {
        descBuffer[descIndex++] = '\0';
        if ((strlen(descBuffer) != 0) && (descCallback != NULL)) {
          descCallback(descBuffer);
        }
        state = CHK_START;
      }
      break;

    case GET_DATE:
      if (ch != '<') {
        dateBuffer[dateIndex++] = ch;
      } else  {
        // Just return the date not the time
        dateBuffer[17] = '\0';
        if ((strlen(dateBuffer) != 0) && (dateCallback != NULL)) {
          dateCallback(dateBuffer);
        }
        state = CHK_START;
      }
      break;
  }
}