5 files changed, 538 insertions, 0 deletions
diff --git a/serd/detail/Copyable.hpp b/serd/detail/Copyable.hpp
new file mode 100644
index 00000000..225fc18c
--- /dev/null
+++ b/serd/detail/Copyable.hpp
@@ -0,0 +1,101 @@
+/*
+  Copyright 2019 David Robillard <http://drobilla.net>
+
+  Permission to use, copy, modify, and/or distribute this software for any
+  purpose with or without fee is hereby granted, provided that the above
+  copyright notice and this permission notice appear in all copies.
+
+  THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+
+#ifndef SERD_DETAIL_COPYABLE_HPP
+#define SERD_DETAIL_COPYABLE_HPP
+
+#include "serd/detail/Wrapper.hpp"
+#include "serd/serd.h"
+
+#include <cstddef>
+#include <memory>
+#include <type_traits>
+
+namespace serd {
+namespace detail {
+
+/// Copy function for a C object
+template <class T>
+using CopyFunc = T* (*)(const T*);
+
+template <class T, Mutable<T>* Copy(const T*), void Free(Mutable<T>*)>
+typename std::enable_if<std::is_const<T>::value, T>::type*
+copy(const T* ptr)
+{
+	return ptr; // Making a view (const reference), do not copy
+}
+
+template <class T,
+          Mutable<T>* Copy(const T*),
+          void        Free(typename std::remove_const<T>::type*)>
+typename std::enable_if<!std::is_const<T>::value, T>::type*
+copy(const T* ptr)
+{
+	return Copy(ptr); // Making a mutable wrapper, copy
+}
+
+/// Generic C++ wrapper for a copyable C object
+template <class T,
+          Mutable<T>* Copy(const T*),
+          bool        Equals(const T*, const T*),
+          void        Free(Mutable<T>*)>
+class Copyable : public Wrapper<T, Free>
+{
+public:
+	explicit Copyable(T* ptr) : Wrapper<T, Free>(ptr) {}
+
+	Copyable(const Copyable& wrapper)
+	    : Wrapper<T, Free>(copy<T, Copy, Free>(wrapper.cobj()))
+	{
+	}
+
+	template <class U, void UFree(Mutable<U>*)>
+	explicit Copyable(const Copyable<U, Copy, Equals, UFree>& wrapper)
+	    : Wrapper<T, Free>(copy<T, Copy, Free>(wrapper.cobj()))
+	{
+	}
+
+	Copyable(Copyable&&) noexcept = default;
+	Copyable& operator=(Copyable&&) noexcept = default;
+	~Copyable() noexcept                     = default;
+
+	Copyable& operator=(const Copyable& wrapper)
+	{
+		this->_ptr = std::unique_ptr<T, Deleter<T, Free>>(
+		        copy<T, Copy, Free>(wrapper.cobj()));
+		return *this;
+	}
+
+	template <class U, void UFree(Mutable<U>*)>
+	bool operator==(const Copyable<U, Copy, Equals, UFree>& wrapper) const
+	{
+		return Equals(this->cobj(), wrapper.cobj());
+	}
+
+	template <class U, void UFree(Mutable<U>*)>
+	bool operator!=(const Copyable<U, Copy, Equals, UFree>& wrapper) const
+	{
+		return !operator==(wrapper);
+	}
+
+protected:
+	explicit Copyable(std::nullptr_t) : Wrapper<T, Free>(nullptr) {}
+};
+
+} // namespace detail
+} // namespace serd
+
+#endif // SERD_DETAIL_COPYABLE_HPP
diff --git a/serd/detail/Flags.hpp b/serd/detail/Flags.hpp
new file mode 100644
index 00000000..bae2da96
--- /dev/null
+++ b/serd/detail/Flags.hpp
@@ -0,0 +1,73 @@
+/*
+  Copyright 2019 David Robillard <http://drobilla.net>
+
+  Permission to use, copy, modify, and/or distribute this software for any
+  purpose with or without fee is hereby granted, provided that the above
+  copyright notice and this permission notice appear in all copies.
+
+  THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+
+#ifndef SERD_DETAIL_FLAGS_HPP
+#define SERD_DETAIL_FLAGS_HPP
+
+#include "serd/serd.h"
+
+#include <type_traits>
+
+namespace serd {
+namespace detail {
+
+/**
+   Type-safe bit flags
+
+  This is a minimal interface for a type-safe bit flags field, which only
+  allows values from the given enum to be set.
+
+  @tparam Flag Enum class of flag values.
+*/
+template <typename Flag>
+class Flags
+{
+public:
+	static_assert(std::is_enum<Flag>::value, "");
+
+	using FlagUnderlyingType = typename std::underlying_type<Flag>::type;
+	using Value = typename std::make_unsigned<FlagUnderlyingType>::type;
+
+	constexpr Flags() noexcept : _value(0) {}
+	constexpr explicit Flags(const Value value) noexcept : _value{value} {}
+
+	// NOLINTNEXTLINE(hicpp-explicit-conversions)
+	constexpr Flags(const Flag f) noexcept
+	    : _value(static_cast<Value>(f))
+	{
+	}
+
+	constexpr Flags operator|(const Flag rhs) const noexcept
+	{
+		return Flags{_value | static_cast<Value>(rhs)};
+	}
+
+	constexpr Flags operator|(const Flags rhs) const noexcept
+	{
+		return Flags{_value | rhs._value};
+	}
+
+	// NOLINTNEXTLINE(hicpp-explicit-conversions)
+	constexpr operator Value() const noexcept { return _value; }
+
+private:
+	Value _value{};
+};
+
+} // namespace detail
+} // namespace serd
+
+#endif // SERD_DETAIL_FLAGS_HPP
diff --git a/serd/detail/Optional.hpp b/serd/detail/Optional.hpp
new file mode 100644
index 00000000..5ca7f83f
--- /dev/null
+++ b/serd/detail/Optional.hpp
@@ -0,0 +1,129 @@
+/*
+  Copyright 2019 David Robillard <http://drobilla.net>
+
+  Permission to use, copy, modify, and/or distribute this software for any
+  purpose with or without fee is hereby granted, provided that the above
+  copyright notice and this permission notice appear in all copies.
+
+  THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+
+#ifndef SERD_DETAIL_OPTIONAL_HPP
+#define SERD_DETAIL_OPTIONAL_HPP
+
+#include "serd/serd.h"
+
+#include <cassert>
+#include <cstddef>
+#include <utility>
+
+namespace serd {
+namespace detail {
+
+struct ConstructNullOptional
+{
+};
+
+/**
+   A simple optional wrapper around a wrapped type with a pointer-like API
+
+   This works like a typical optional type, but only works with Wrapper types,
+   and exploits the fact that these are interally just pointers to avoid adding
+   space overhead for an "is_set" flag, like a generic optional class would.
+
+   Types must explicitly opt-in to being optional by providing a constructor
+   that takes a single ContructNullOptional argument.  This constructor should
+   only be used by the Optional implementation, which guarantees that such an
+   object will not be used except by calling its cobj() method.
+*/
+template <typename T>
+class Optional
+{
+public:
+	using CType = typename T::CType;
+
+	Optional() : _value(nullptr) {}
+
+	// NOLINTNEXTLINE(hicpp-explicit-conversions, modernize-pass-by-value)
+	Optional(const T& value) : _value(value) {}
+
+	// NOLINTNEXTLINE(hicpp-explicit-conversions)
+	Optional(T&& value) : _value(std::move(value)) {}
+
+	template <typename U,
+	          typename = typename std::enable_if<
+	                  std::is_convertible<U, T>::value>::type>
+	// NOLINTNEXTLINE(hicpp-explicit-conversions)
+	Optional(U&& value) : _value(std::forward<U>(value))
+	{
+	}
+
+	void reset() { _value = T{nullptr}; }
+
+	const T& operator*() const
+	{
+		assert(_value.cobj());
+		return _value;
+	}
+
+	T& operator*()
+	{
+		assert(_value.cobj());
+		return _value;
+	}
+
+	const T* operator->() const
+	{
+		assert(_value.cobj());
+		return &_value;
+	}
+
+	T* operator->()
+	{
+		assert(_value.cobj());
+		return &_value;
+	}
+
+	bool operator==(const Optional& optional)
+	{
+		return (!*this && !optional) ||
+		       (*this && optional && _value == optional._value);
+	}
+
+	bool operator!=(const Optional& optional) { return !operator==(optional); }
+
+	explicit operator bool() const { return _value.cobj(); }
+	bool     operator!() const { return !_value.cobj(); }
+
+	inline CType*       cobj() { return _value.cobj(); }
+	inline const CType* cobj() const { return _value.cobj(); }
+
+private:
+	T _value;
+};
+
+} // namespace detail
+
+template <class T>
+constexpr detail::Optional<T>
+make_optional(T&& value)
+{
+	return detail::Optional<T>{std::forward<T>(value)};
+}
+
+template <class T, class... Args>
+constexpr detail::Optional<T>
+make_optional(Args&&... args)
+{
+	return detail::Optional<T>{std::forward<Args>(args)...};
+}
+
+} // namespace serd
+
+#endif // SERD_DETAIL_OPTIONAL_HPP
diff --git a/serd/detail/StringView.hpp b/serd/detail/StringView.hpp
new file mode 100644
index 00000000..0915daed
--- /dev/null
+++ b/serd/detail/StringView.hpp
@@ -0,0 +1,148 @@
+/*
+  Copyright 2019 David Robillard <http://drobilla.net>
+
+  Permission to use, copy, modify, and/or distribute this software for any
+  purpose with or without fee is hereby granted, provided that the above
+  copyright notice and this permission notice appear in all copies.
+
+  THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+
+#ifndef SERD_DETAIL_STRINGVIEW_HPP
+#define SERD_DETAIL_STRINGVIEW_HPP
+
+#include "serd/serd.h"
+
+#include <algorithm>
+#include <cstddef>
+#include <cstring>
+#include <ostream>
+#include <stdexcept>
+#include <string>
+
+namespace serd {
+namespace detail {
+
+/**
+   Immutable slice of a string.
+
+   This is a minimal implementation that is compatible with std::string_view
+   and std::string for most basic use cases.  This could be replaced with
+   std::string_view once C++17 support can be relied on.
+*/
+class StringView
+{
+public:
+	using char_type       = char;
+	using size_type       = size_t;
+	using traits_type     = std::char_traits<char>;
+	using value_type      = char;
+	using pointer         = value_type*;
+	using const_pointer   = const value_type*;
+	using reference       = value_type&;
+	using const_reference = const value_type&;
+	using iterator        = const char*;
+	using const_iterator  = const char*;
+
+	static constexpr size_type npos = size_t(-1);
+
+	constexpr StringView() noexcept : _str{nullptr}, _len{0U} {}
+
+	constexpr StringView(const char* const str, const size_t len) noexcept
+	    : _str{str}, _len{len}
+	{
+	}
+
+	// NOLINTNEXTLINE(hicpp-explicit-conversions)
+	StringView(const char* const str) noexcept
+	    : _str{str}, _len{str ? strlen(str) : 0}
+	{
+	}
+
+	// NOLINTNEXTLINE(hicpp-explicit-conversions)
+	StringView(const std::string& str) noexcept
+	    : _str{str.c_str()}, _len{str.length()}
+	{
+	}
+
+	constexpr size_t      size() const { return _len; }
+	constexpr size_t      length() const { return _len; }
+	constexpr bool        empty() const { return _len == 0; }
+	constexpr const char* c_str() const { return _str; }
+	constexpr const char* data() const { return _str; }
+	constexpr const char& front() const { return _str[0]; }
+	constexpr const char& back() const { return _str[_len - 1]; }
+
+	constexpr const_iterator begin() const { return _str; }
+	constexpr const_iterator end() const { return _str + _len; }
+	constexpr const_iterator cbegin() const { return begin(); }
+	constexpr const_iterator cend() const { return end(); }
+
+	constexpr const char& operator[](size_t pos) const { return _str[pos]; }
+
+	const char& at(size_t pos) const
+	{
+		if (pos >= size()) {
+			throw std::out_of_range("serd::StringView::at pos");
+		}
+
+		return _str[pos];
+	}
+
+	StringView substr(size_t pos, size_t n = npos) const
+	{
+		if (pos > size()) {
+			throw std::out_of_range("serd::StringView::substr pos");
+		}
+
+		return StringView{data() + pos, std::min(size() - pos, n)};
+	}
+
+	template <class Alloc = std::allocator<char>>
+	std::basic_string<char, traits_type, Alloc>
+	str(const Alloc& alloc = {}) const
+	{
+		return std::basic_string<char, traits_type, Alloc>(
+		        data(), size(), alloc);
+	}
+
+	// NOLINTNEXTLINE(hicpp-explicit-conversions)
+	explicit operator std::string() const { return str(); }
+
+	// NOLINTNEXTLINE(hicpp-explicit-conversions)
+	explicit operator const char*() const { return _str; }
+
+private:
+	const char* const _str{};
+	const size_t      _len{};
+};
+
+inline bool
+operator==(const detail::StringView& lhs, const std::string& rhs)
+{
+	return lhs.length() == rhs.length() && rhs == lhs.c_str();
+}
+
+inline bool
+operator==(const detail::StringView& lhs, const char* rhs)
+{
+	return !strncmp(lhs.c_str(), rhs, lhs.length());
+}
+
+inline std::ostream&
+operator<<(std::ostream& os, const StringView& str)
+{
+	os.write(str.data(), std::streamsize(str.size()));
+	return os;
+}
+
+} // namespace detail
+} // namespace serd
+
+#endif // SERD_DETAIL_STRINGVIEW_HPP
diff --git a/serd/detail/Wrapper.hpp b/serd/detail/Wrapper.hpp
new file mode 100644
index 00000000..5048dfd1
--- /dev/null
+++ b/serd/detail/Wrapper.hpp
@@ -0,0 +1,87 @@
+/*
+  Copyright 2019 David Robillard <http://drobilla.net>
+
+  Permission to use, copy, modify, and/or distribute this software for any
+  purpose with or without fee is hereby granted, provided that the above
+  copyright notice and this permission notice appear in all copies.
+
+  THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+
+#ifndef SERD_DETAIL_WRAPPER_HPP
+#define SERD_DETAIL_WRAPPER_HPP
+
+#include "serd/serd.h"
+
+#include <cstddef>
+#include <memory>
+
+namespace serd {
+namespace detail {
+
+template <typename T>
+class Optional;
+
+// Free function for a C object
+template <typename T>
+using FreeFunc = void (*)(T*);
+
+template <class T>
+using Mutable = typename std::remove_const<T>::type;
+
+/// Callable deleter for a C object, noopt for const pointers
+template <typename T, void Free(Mutable<T>*)>
+struct Deleter
+{
+	template <typename = std::enable_if<!std::is_const<T>::value>>
+	void operator()(typename std::remove_const<T>::type* ptr)
+	{
+		Free(ptr);
+	}
+
+	template <typename = std::enable_if<std::is_const<T>::value>>
+	void operator()(const T*)
+	{
+	}
+};
+
+/// Generic C++ wrapper for a C object
+template <typename T, void FreeFunc(Mutable<T>*)>
+class Wrapper
+{
+public:
+	using CType = T;
+
+	explicit Wrapper(T* ptr) : _ptr(ptr) {}
+
+	Wrapper(Wrapper&& wrapper) noexcept = default;
+	Wrapper& operator=(Wrapper&& wrapper) noexcept = default;
+
+	Wrapper(const Wrapper&) = delete;
+	Wrapper& operator=(const Wrapper&) = delete;
+
+	~Wrapper() = default;
+
+	T*       cobj() { return _ptr.get(); }
+	const T* cobj() const { return _ptr.get(); }
+
+protected:
+	friend class detail::Optional<T>;
+
+	explicit Wrapper(std::nullptr_t) : _ptr(nullptr) {}
+
+	void reset() { _ptr.reset(); }
+
+	std::unique_ptr<T, Deleter<T, FreeFunc>> _ptr;
+};
+
+} // namespace detail
+} // namespace serd
+
+#endif // SERD_DETAIL_WRAPPER_HPP