src/cpp-common: improve C++ UUID utilities

[babeltrace.git] / src / cpp-common / uuid.hpp

diff --git a/src/cpp-common/uuid.hpp b/src/cpp-common/uuid.hpp
new file mode 100644 (file)
index 0000000..935091f
--- /dev/null
+++ b/src/cpp-common/uuid.hpp
@@ -0,0 +1,154 @@
+/*
+ * Copyright (c) 2022 Francis Deslauriers <francis.deslauriers@efficios.com>
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+#ifndef BABELTRACE_CPP_COMMON_UUID_HPP
+#define BABELTRACE_CPP_COMMON_UUID_HPP
+
+#include <algorithm>
+#include <array>
+#include <cstdint>
+#include <string>
+
+#include "common/assert.h"
+#include "common/uuid.h"
+#include "uuid-view.hpp"
+
+namespace bt2_common {
+
+/*
+ * A universally unique identifier.
+ *
+ * A `Uuid` object contains its UUID data: see `UuidView` to have a
+ * UUID view on existing UUID data.
+ */
+class Uuid final
+{
+public:
+    using Val = UuidView::Val;
+    using ConstIter = UuidView::ConstIter;
+
+public:
+    /*
+     * Builds a nil UUID.
+     */
+    explicit Uuid() noexcept = default;
+
+    explicit Uuid(const Val * const uuid) noexcept
+    {
+        this->_setFromPtr(uuid);
+    }
+
+    explicit Uuid(const char * const str) noexcept
+    {
+        const auto ret = bt_uuid_from_str(str, _mUuid.data());
+        BT_ASSERT(ret == 0);
+    }
+
+    explicit Uuid(const std::string& str) noexcept : Uuid {str.c_str()}
+    {
+    }
+
+    explicit Uuid(const UuidView& view) noexcept : Uuid {view.data()}
+    {
+    }
+
+    Uuid(const Uuid&) noexcept = default;
+    Uuid& operator=(const Uuid&) noexcept = default;
+
+    Uuid& operator=(const Val * const uuid) noexcept
+    {
+        this->_setFromPtr(uuid);
+        return *this;
+    }
+
+    static Uuid generate() noexcept
+    {
+        bt_uuid_t uuidGen;
+
+        bt_uuid_generate(uuidGen);
+        return Uuid {uuidGen};
+    }
+
+    std::string str() const
+    {
+        return this->_view().str();
+    }
+
+    bool operator==(const Uuid& other) const noexcept
+    {
+        return this->_view() == other._view();
+    }
+
+    bool operator!=(const Uuid& other) const noexcept
+    {
+        return this->_view() != other._view();
+    }
+
+    bool operator<(const Uuid& other) const noexcept
+    {
+        return this->_view() < other._view();
+    }
+
+    /*
+     * The returned UUID view must not outlive the UUID object.
+     */
+    operator UuidView() const noexcept
+    {
+        return this->_view();
+    }
+
+    static constexpr std::size_t size() noexcept
+    {
+        return UuidView::size();
+    }
+
+    const Val *data() const noexcept
+    {
+        return _mUuid.data();
+    }
+
+    Val operator[](const std::size_t index) const noexcept
+    {
+        return this->_view()[index];
+    }
+
+    ConstIter begin() const noexcept
+    {
+        return this->_view().begin();
+    }
+
+    ConstIter end() const noexcept
+    {
+        return this->_view().end();
+    }
+
+    bool isNil() const noexcept
+    {
+        return this->_view().isNil();
+    }
+
+private:
+    /*
+     * std::copy_n() won't throw when simply copying bytes below,
+     * therefore this method won't throw.
+     */
+    void _setFromPtr(const Val * const uuid) noexcept
+    {
+        BT_ASSERT(uuid);
+        std::copy_n(uuid, BT_UUID_LEN, std::begin(_mUuid));
+    }
+
+    UuidView _view() const noexcept
+    {
+        return UuidView {_mUuid.data()};
+    }
+
+    std::array<Val, UuidView::size()> _mUuid = {};
+};
+
+} /* namespace bt2_common */
+
+#endif /* BABELTRACE_CPP_COMMON_UUID_HPP */