validate_flag.h

// Copyright 2014 Google LLC. All rights reserved.
//
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file or at
// https://developers.google.com/open-source/licenses/bsd
//
// Flag validation help functions.
 
#ifndef PACKAGER_APP_VALIDATE_FLAG_H_
#define PACKAGER_APP_VALIDATE_FLAG_H_
 
#include <string>
 
#include <absl/strings/str_format.h>
 
namespace shaka {
 
void PrintError(const std::string& error_message);
 
void PrintWarning(const std::string& warning_message);
 
//         and cannot be empty; If condition is false, then this flag should
//         not be set.
template <class FlagType>
bool ValidateFlag(const char* flag_name,
                  const FlagType& flag_value,
                  bool condition,
                  bool optional,
                  const char* label) {
  if (flag_value.empty()) {
    if (!optional && condition) {
      PrintError(absl::StrFormat("--%s is required if %s.", flag_name, label));
      return false;
    }
  } else if (!condition) {
    PrintError(absl::StrFormat("--%s should be specified only if %s.",
                               flag_name, label));
    return false;
  }
  return true;
}
 
}  // namespace shaka
 
#endif  // PACKAGER_APP_VALIDATE_FLAG_H_