Arduino便利関数

util.cpp

// Streamから一行読み込む関数
String readLine(Stream* s){
  String ret;
  bool start = false;
  while(true){
    int ch = s->read();
    if(ch < 0){
      return ret;
    }
    
    if(ch == '\r' || ch == '\n'){
      if(start){
        return ret;
      }else{
        continue;
      }
    }
    start = true;
    ret += (char)ch;
  }
}

//適当なdelimiterで区切られた文字列のうち指定されたところだけ読み込む関数
String splitString(String line,char delimiter,uint8_t index){
  uint32_t start = 0;
  uint32_t end = line.length();
  for(uint32_t i = 0 ; i < line.length() ; i++){
    unsigned int c = line[i];
    if(c == 0){
      // unexpeced termination of line
      break;
    }else if(c == delimiter){
      if(index == 0){
        end = i;
        break;
      }else if(index == 1){
        start = i+1;
      }
      index --;
    }
  }
  if(index == 0){
    return line.substring(start,end);
  }else{
    return String();
  }
}

// bytes列をhex stringに変換するヘルパ
inline char itoc(const uint8_t i) {
    return i < 10 ? i+0x30 : i+0x57; // 0x57 = 0x61('a') - 0x0a
    //return i < 10 ? i+0x30 : i+0x37; // 0x37 = 0x41('A') - 0x0a
}

// bytes列をhex stringに変換
// strbufのサイズは len*2+1
const char* BytesToHexStr(const uint8_t * const data, char* strbuf, size_t len){
    for(size_t i = 0 ; i < len ; i ++){
        strbuf[i*2+1] = itoc(data[i] & 0xf);
        strbuf[i*2] = itoc(data[i] >> 4);
    }
    strbuf[len*2] = '\0';
    return strbuf;
}