mpd/src/util/StringPointer.hxx
2017-01-17 11:54:55 +01:00

73 lines
2.1 KiB
C++

/*
* Copyright (C) 2015 Max Kellermann <max.kellermann@gmail.com>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* FOUNDATION OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef STRING_POINTER_HXX
#define STRING_POINTER_HXX
/**
* Simple OO wrapper for a const string pointer.
*/
template<typename T=char>
class StringPointer {
public:
typedef T value_type;
typedef T &reference_type;
typedef const T &const_reference_type;
typedef T *pointer_type;
typedef const T *const_pointer_type;
static constexpr value_type SENTINEL = '\0';
private:
const_pointer_type value;
public:
StringPointer() = default;
constexpr StringPointer(const_pointer_type _value)
:value(_value) {}
/**
* Check if this is a "nulled" instance. A "nulled" instance
* must not be used.
*/
constexpr bool IsNull() const {
return value == nullptr;
}
constexpr const_pointer_type c_str() const {
return value;
}
bool empty() const {
return *value == SENTINEL;
}
};
#endif