StrRef.h

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// Copyright Onix Solutions Limited [OnixS]. All rights reserved.
//
// This software owned by Onix Solutions Limited [OnixS] and is
// protected by copyright law and international copyright treaties.
//
// Access to and use of the software is governed by the terms of the applicable
// OnixS Software Services Agreement (the Agreement) and Customer end user license
// agreements granting a non-assignable, non-transferable and non-exclusive license
// to use the software for it's own data processing purposes under the terms defined
// in the Agreement.
//
// Except as otherwise granted within the terms of the Agreement, copying or
// reproduction of any part of this source code or associated reference material
// to any other location for further reproduction or redistribution, and any
// amendments to this copyright notice, are expressly prohibited.
//
// Any reproduction or redistribution for sale or hiring of the Software not in
// accordance with the terms of the Agreement is a violation of copyright law.
//
 
#pragma once
 
#include <OnixS/CME/MDH/ABI.h>
#include <OnixS/CME/MDH/messaging/Aliases.h>
#include <OnixS/CME/MDH/messaging/String.h>
#include <OnixS/CME/MDH/messaging/Utils.h>
#include <OnixS/CME/MDH/messaging/Memory.h>
 
#include <algorithm>
#include <cassert>
#include <cstddef>
#include <cstring>
#include <limits>
#include <ostream>
#include <stdexcept>
#include <string>
 
#if defined(ONIXS_CMEMDH_CXX17)
#  include <string_view>
#endif
 
ONIXS_CMEMDH_MESSAGING_NAMESPACE_BEGIN
 
#if defined(ONIXS_CMEMDH_CXX17)
 
using StrRef = std::basic_string_view<Char>;
 
#else

ONIXS_CMEMDH_EXPORTED
ONIXS_CMEMDH_COLDPATH
ONIXS_CMEMDH_NORETURN
void throwInvalidIndex(size_t, size_t);

class StrRef
{
public:
    typedef size_t size_type;

    typedef const Char* const_iterator;
    typedef const_iterator iterator;
    typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
    typedef const_reverse_iterator reverse_iterator;

    constexpr StrRef()
        : items_(nullptr)
        , size_(0)
    {
    }

    constexpr StrRef(const Char* chars, size_t size) noexcept
        : items_(chars)
        , size_((ONIXS_CMEMDH_ASSERT(size <= (std::numeric_limits<size_type>::max)()), static_cast<size_type>(size)))
    {
    }

    StrRef(const Char* chars) noexcept
        : items_(chars)
        , size_(0)
    {
        assert(chars);
 
        constexpr size_type maxLen = (std::numeric_limits<UInt16>::max)();
 
        size_ = numericCast<size_type>(strnlen(chars, maxLen));
 
        assert(size_ < maxLen);
    }

    StrRef(const std::string& string)
        : items_(string.c_str())
        , size_(static_cast<size_type>(string.length()))
    {
        assert(string.length() <= (std::numeric_limits<size_type>::max)());
    }

    ONIXS_CMEMDH_NODISCARD
    bool empty() const noexcept
    {
        return (0 == size_);
    }

    ONIXS_CMEMDH_NODISCARD
    constexpr const Char* data() const noexcept
    {
        return items_;
    }

    ONIXS_CMEMDH_NODISCARD
    constexpr size_type size() const noexcept
    {
        return size_;
    }
 
    constexpr ONIXS_CMEMDH_NODISCARD
        size_type
        length() const noexcept
    {
        return size_;
    }

    ONIXS_CMEMDH_NODISCARD
    const_iterator begin() const noexcept
    {
        assert(items_);
        return items_;
    }

    ONIXS_CMEMDH_NODISCARD
    const_iterator end() const noexcept
    {
        assert(items_);
        return (items_ + size_);
    }

    ONIXS_CMEMDH_NODISCARD
    const_iterator cbegin() const noexcept
    {
        return begin();
    }

    ONIXS_CMEMDH_NODISCARD
    const_iterator cend() const noexcept
    {
        return end();
    }

    ONIXS_CMEMDH_NODISCARD
    const_reverse_iterator rbegin() const noexcept
    {
        return const_reverse_iterator(end());
    }

    ONIXS_CMEMDH_NODISCARD
    const_reverse_iterator rend() const noexcept
    {
        return const_reverse_iterator(begin());
    }

    ONIXS_CMEMDH_NODISCARD
    const_reverse_iterator crbegin() const noexcept
    {
        return rbegin();
    }

    ONIXS_CMEMDH_NODISCARD
    const_reverse_iterator crend() const noexcept
    {
        return rend();
    }

    ONIXS_CMEMDH_NODISCARD
    const Char& operator[](size_type index) const noexcept
    {
        assert(index < size_);
        assert(items_);
 
        return items_[index];
    }

    ONIXS_CMEMDH_NODISCARD
    const Char& at(size_type index) const
    {
        assert(items_);
 
        if (index < size_)
            return items_[index];
 
        throwInvalidIndex(index, size_);
    }

    const Char& front() const noexcept
    {
        assert(!empty());
        return (*this)[0];
    }

    const Char& back() const noexcept
    {
        assert(!empty());
        return (*this)[size_ - 1];
    }

    void swap(StrRef& other) noexcept
    {
        std::swap(items_, other.items_);
 
        std::swap(size_, other.size_);
    }

    operator std::basic_string<Char>() const
    {
        return std::basic_string<Char>(data(), size());
    }
 
private:
    const Char* items_;

    size_type size_;
};

ONIXS_CMEMDH_NODISCARD
inline bool operator==(const StrRef& left, const StrRef& right)
{
    if (left.size() != right.size())
        return false;
 
    if (left.empty())
    {
        assert(right.empty());
        return true;
    }
 
    assert(left.data());
    assert(right.data());
 
    return (0 == memcmp(left.data(), right.data(), left.size()));
}

ONIXS_CMEMDH_NODISCARD
inline bool operator!=(const StrRef& left, const StrRef& right)
{
    return !(left == right);
}

ONIXS_CMEMDH_NODISCARD
inline bool operator<(const StrRef& left, const StrRef& right)
{
    const int result = memcmp(left.data(), right.data(), left.size() < right.size() ? left.size() : right.size());
 
    return (0 != result ? (0 > result) : (left.size() < right.size()));
}

ONIXS_CMEMDH_NODISCARD
inline bool operator>(const StrRef& left, const StrRef& right)
{
    return (right < left);
}

inline std::ostream& operator<<(std::ostream& stream, const StrRef& text)
{
    stream.write(text.data(), text.size());
 
    return stream;
}
 
ONIXS_CMEMDH_NODISCARD StrRef toStrRef(const std::string&);
ONIXS_CMEMDH_NODISCARD StrRef toStrRef(const Char*) noexcept;

ONIXS_CMEMDH_NODISCARD
inline bool operator==(const StrRef& ref, const std::string& str)
{
    return ref == toStrRef(str);
}

ONIXS_CMEMDH_NODISCARD
inline bool operator!=(const StrRef& ref, const std::string& str)
{
    return ref != toStrRef(str);
}

ONIXS_CMEMDH_NODISCARD
inline bool operator==(const std::string& str, const StrRef& ref)
{
    return ref == toStrRef(str);
}

ONIXS_CMEMDH_NODISCARD
inline bool operator!=(const std::string& str, const StrRef& ref)
{
    return ref != toStrRef(str);
}

ONIXS_CMEMDH_NODISCARD
inline bool operator==(const StrRef& ref, const Char* str)
{
    return ref == toStrRef(str);
}

ONIXS_CMEMDH_NODISCARD
inline bool operator!=(const StrRef& ref, const Char* str)
{
    return ref != toStrRef(str);
}

ONIXS_CMEMDH_NODISCARD
inline bool operator==(const Char* str, const StrRef& ref)
{
    return ref == toStrRef(str);
}

ONIXS_CMEMDH_NODISCARD
inline bool operator!=(const Char* str, const StrRef& ref)
{
    return ref != toStrRef(str);
}
 
#endif

ONIXS_CMEMDH_NODISCARD
inline StrRef toStrRef(const std::string& str)
{
    return StrRef(str);
}

ONIXS_CMEMDH_NODISCARD
inline StrRef toStrRef(const Char* cStr) noexcept
{
    return (cStr != nullptr) ? StrRef(cStr) : StrRef();
}
 
ONIXS_CMEMDH_NODISCARD
inline StrRef toStrRef(const Char* begin, const Char* end) noexcept
{
    assert(begin <= end);
 
    return Messaging::StrRef(begin, byteDistance(end, begin));
}
 
template <size_t Size>
ONIXS_CMEMDH_NODISCARD
inline constexpr StrRef constructStrRef(const char (&value)[Size]) noexcept
{
    return StrRef(value, Size - 1);
}
 
template <size_t Size>
ONIXS_CMEMDH_NODISCARD inline constexpr StrRef strRefFromCharArray(const char (&value)[Size]) noexcept
{
    return StrRef(value, Size);
}

ONIXS_CMEMDH_NODISCARD
inline std::string toStr(StrRef ref)
{
    return std::string(ref.data(), ref.size());
}

inline void toStr(std::string& str, StrRef ref)
{
    str.append(ref.data(), ref.size());
}
 
ONIXS_CMEMDH_MESSAGING_NAMESPACE_END