m/b/simple: add simple buffer implementation

CMakeLists.txt

@@ -349,6 +349,8 @@ list (
     matrix3.cpp
     matrix4.cpp
     matrix.hpp
+    memory/buffer/simple.cpp
+    memory/buffer/simple.hpp
     memory/deleter.cpp
     memory/deleter.hpp
     nocopy.hpp
@@ -567,6 +569,7 @@ if (TESTS)
         maths/fast
         matrix
         memory/deleter
+        memory/buffer/simple
         parallel/queue
         parse
         point

memory/buffer/simple.cpp

@@ -0,0 +1,28 @@
+/*
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * Copyright 2018 Danny Robson <danny@nerdcruft.net>
+ */
+
+#include "simple.hpp"
+
+using cruft::memory::buffer::simple;
+
+
+///////////////////////////////////////////////////////////////////////////////
+simple::simple (size_t _size)
+    : m_base (new u08[_size])
+    , m_size (_size)
+{ ; }
+
+
+///////////////////////////////////////////////////////////////////////////////
+simple::value_type* simple::begin (void)& { return m_base.get (); }
+simple::value_type* simple::end   (void)& { return begin () + m_size; }
+
+
+//-----------------------------------------------------------------------------
+simple::value_type const* simple::begin (void) const& { return m_base.get (); }
+simple::value_type const* simple::end   (void) const& { return begin () + m_size; }

memory/buffer/simple.hpp

@@ -0,0 +1,54 @@
+/*
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * Copyright 2018 Danny Robson <danny@nerdcruft.net>
+ */
+
+#pragma once
+
+#include "../../std.hpp"
+
+#include <cstddef>
+#include <memory>
+
+
+namespace cruft::memory::buffer {
+    /// Implements a trivial statically allocated memory buffer with a fixed
+    /// construction time and no other fancy tricks (just something trivial
+    /// like new/delete).
+    ///
+    /// The actual allocation size is guaranteed to be _at least_ the
+    /// specified size. It may be larger if the underlying implementation
+    /// requires page alignment or other system specific details.
+    ///
+    /// Useful as a trivial universal implementation of the buffer concept.
+    class simple {
+    public:
+        using value_type = u08;
+
+        explicit simple (size_t _size);
+
+        simple (const simple&) = delete;
+        simple (simple &&) = default;
+        simple& operator= (const simple&) = delete;
+        simple& operator= (simple &&);
+
+        value_type* begin (void)&;
+        value_type* end   (void)&;
+
+        value_type const* cbegin (void)&;
+        value_type const* cend   (void)&;
+
+        value_type const* begin (void) const&;
+        value_type const* end   (void) const&;
+
+        std::size_t size (void) const;
+        std::size_t capacity (void) const;
+
+    private:
+        std::unique_ptr<u08> m_base;
+        std::size_t m_size;
+    };
+}

test/memory/buffer/simple.cpp

@@ -0,0 +1,26 @@
+/*
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * Copyright 2018 Danny Robson <danny@nerdcruft.net>
+ */
+
+#include "memory/buffer/simple.hpp"
+
+#include <cstdlib>
+#include <algorithm>
+
+
+///////////////////////////////////////////////////////////////////////////////
+int
+main (int, char**)
+{
+    // Make a buffer and fill it with non-zero elements. This is just enough
+    // to test that we can write to the memory without (obviously) crashing.
+    static constexpr std::size_t elements = 2049;
+    cruft::memory::buffer::simple buf (elements);
+    std::fill (std::begin (buf), std::end (buf), 0xff);
+
+    return EXIT_SUCCESS;
+}