    snprintf(buf.get(), size, format.c_str(), args...);
    return std::string(buf.get(), buf.get() + size - 1);
  }
  
  std::string getenv_default(const char* env_var, const char* suffix, const char* default_val);
  std::string tohex(const uint8_t* buf, size_t buf_size);
  std::string hexdump(const std::string& in);
  std::string base_name(std::string const& path);
  std::string dir_name(std::string const& path);
  
 
</s> remove std::string getenv_default(const char* env_var, const char * suffix, const char* default_val) {
  const char* env_val = getenv(env_var);
  if (env_val != NULL) {
    return std::string(env_val) + std::string(suffix);
  } else {
    return std::string(default_val);
  }
 </s> add std::string getenv(const char* key, const char* default_val) {
  const char* val = ::getenv(key);
  return val ? val : default_val;
}

int getenv(const char* key, int default_val) {
  const char* val = ::getenv(key);
  return val ? atoi(val) : default_val;
}

float getenv(const char* key, float default_val) {
  const char* val = ::getenv(key);
  return val ? atof(val) : default_val; </s> remove   if (path == default_params_path) {
 </s> add   if (path == Path::params()) { </s> remove const std::string DEFAULT_LOG_ROOT =
    Hardware::PC() ? util::getenv_default("HOME", "/.comma/media/0/realdata", "/data/media/0/realdata")
                   : "/data/media/0/realdata";

const std::string LOG_ROOT = util::getenv_default("LOG_ROOT", "", DEFAULT_LOG_ROOT.c_str());
 </s> add const std::string LOG_ROOT = Path::log_root(); </s> remove const std::string default_params_path = Hardware::PC() ? util::getenv_default("HOME", "/.comma/params", "/data/params")
                                                       : "/data/params";
const std::string persistent_params_path = Hardware::PC() ? default_params_path : "/persist/comma/params";

 </s> add  </s> remove Params::Params(bool persistent_param) : Params(persistent_param ? persistent_params_path : default_params_path) {}
 </s> add Params::Params(bool persistent_param) : Params(persistent_param ? Path::persistent_params() : Path::params()) {}
std::string getenv(const char* key, const char* default_val = "");
int getenv(const char* key, int default_val);
float getenv(const char* key, float default_val);

    snprintf(buf.get(), size, format.c_str(), args...);
    return std::string(buf.get(), buf.get() + size - 1);
  }
  
std::string getenv(const char* key, const char* default_val = "");
int getenv(const char* key, int default_val);
float getenv(const char* key, float default_val);

  std::string tohex(const uint8_t* buf, size_t buf_size);
  std::string hexdump(const std::string& in);
  std::string base_name(std::string const& path);
  std::string dir_name(std::string const& path);
  
keep keep keep keep replace keep keep keep keep keep
 hw.h: move Hardware-related paths to namespace Path (#21826)

* refactor getenv and path

* apply review 
selfdrive/common/util.h