char_cast.h

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// Copyright (c) 2025, Oracle and/or its affiliates.
//
// This program is free software; you can redistribute it and/or modify
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// as published by the Free Software Foundation.
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#ifndef MYSQL_UTILS_CHAR_CAST_H
#define MYSQL_UTILS_CHAR_CAST_H
 
/// @file
/// Experimental API header
 
#include <cstddef>                   // byte
#include <utility>                   // forward
#include "mysql/meta/is_charlike.h"  // Is_charlike
 
/// @addtogroup GroupLibsMysqlUtils
/// @{
 
namespace mysql::utils {
 
// cast a reference to an Is_charlike type, to char &.
template <mysql::meta::Is_charlike Char_t = char>
Char_t &char_cast(mysql::meta::Is_charlike auto &ref) {
  return reinterpret_cast<Char_t &>(ref);
}
 
// cast a const reference to an Is_charlike type, to const char &.
template <mysql::meta::Is_charlike Char_t = char>
const Char_t &char_cast(const mysql::meta::Is_charlike auto &ref) {
  return reinterpret_cast<const Char_t &>(ref);
}
 
// cast a pointer to an Is_charlike type, to char *.
template <mysql::meta::Is_charlike Char_t = char>
Char_t *char_cast(mysql::meta::Is_charlike auto *ptr) {
  return reinterpret_cast<Char_t *>(ptr);
}
 
// cast a const pointer to an Is_charlike type, to const char *.
template <mysql::meta::Is_charlike Char_t = char>
const Char_t *char_cast(const mysql::meta::Is_charlike auto *ptr) {
  return reinterpret_cast<const Char_t *>(ptr);
}
 
/// Shorthand for `char_cast<unsigned char>`.
template <class Type_t>
decltype(auto) uchar_cast(Type_t &&value) {
  return char_cast<unsigned char>(std::forward<Type_t>(value));
}
 
/// Shorthand for `char_cast<std::byte>`.
template <class Type_t>
decltype(auto) byte_cast(Type_t &&value) {
  return char_cast<std::byte>(std::forward<Type_t>(value));
}
 
}  // namespace mysql::utils
 
// addtogroup GroupLibsMysqlUtils
/// @}
 
#endif  // ifndef MYSQL_UTILS_CHAR_CAST_H