From ee3581fd7dbacc981a26ad32d90057d572825d87 Mon Sep 17 00:00:00 2001
From: Simon Hoinkis <simon.hoinkis@apex.ai>
Date: Mon, 17 Apr 2023 17:42:18 +0200
Subject: [PATCH] iox-#180 Implement move operations for 'iox::span'

Signed-off-by: Simon Hoinkis <simon.hoinkis@apex.ai>
---
 .../test/moduletests/test_vocabulary_span.cpp |  2 +-
 .../vocabulary/include/iox/detail/span.inl    | 25 ++++++++++++--
 iceoryx_dust/vocabulary/include/iox/span.hpp  | 33 ++++++++++++++++---
 3 files changed, 52 insertions(+), 8 deletions(-)

diff --git a/iceoryx_dust/test/moduletests/test_vocabulary_span.cpp b/iceoryx_dust/test/moduletests/test_vocabulary_span.cpp
index ae30397fd1..cc0dd744f8 100644
--- a/iceoryx_dust/test/moduletests/test_vocabulary_span.cpp
+++ b/iceoryx_dust/test/moduletests/test_vocabulary_span.cpp
@@ -315,7 +315,7 @@ TEST(span_test, CheckConstexprIterOfSpan)
 {
     ::testing::Test::RecordProperty("TEST_ID", "8764fcfb-27df-4f39-b8cd-56bf881db382");
     static constexpr int arr[] = {1, 6, 1, 8, 0};
-    constexpr span<const int> span(arr);
+    IOX_MAYBE_UNUSED constexpr span<const int> span(arr);
 
     // Explicitly not use EXPECT_TRUE here to be able to execute the test case during compile-time
     // 'static_assert' is not possible as not being supported with GCC5
diff --git a/iceoryx_dust/vocabulary/include/iox/detail/span.inl b/iceoryx_dust/vocabulary/include/iox/detail/span.inl
index faa1857d5a..085c136e6a 100644
--- a/iceoryx_dust/vocabulary/include/iox/detail/span.inl
+++ b/iceoryx_dust/vocabulary/include/iox/detail/span.inl
@@ -124,6 +124,25 @@ inline constexpr span<T, Extent>::span(const span<U, OtherExtent>& other)
 {
 }
 
+template <typename T, uint64_t Extent>
+inline constexpr span<T, Extent>::span(span&& other) noexcept
+    : span_storage_t(std::move(other))
+{
+    *this = std::move(other);
+}
+
+template <typename T, uint64_t Extent>
+inline constexpr span<T, Extent>& span<T, Extent>::operator=(span&& other) noexcept
+{
+    if (this != &other)
+    {
+        span_storage_t::operator=(std::move(other));
+        m_data = other.m_data;
+        other.m_data = nullptr;
+    }
+    return *this;
+}
+
 template <typename T, uint64_t Extent>
 template <uint64_t Count>
 inline constexpr span<T, Count> span<T, Extent>::first() const noexcept
@@ -254,14 +273,14 @@ constexpr uint64_t span<T, Extent>::extent;
 
 // object representation
 template <typename T, uint64_t X>
-span<const uint8_t, (X == DYNAMIC_EXTENT ? DYNAMIC_EXTENT : sizeof(T) * X)> as_bytes(span<T, X> s) noexcept
+inline span<const uint8_t, (X == DYNAMIC_EXTENT ? DYNAMIC_EXTENT : sizeof(T) * X)> as_bytes(span<T, X> s) noexcept
 {
     // NOLINTNEXTLINE(cppcoreguidelines-pro-type-reinterpret-cast)
     return {reinterpret_cast<const uint8_t*>(s.data()), s.size_bytes()};
 }
 
-template <typename T, uint64_t X, typename = std::enable_if_t<!std::is_const<T>::value>>
-span<uint8_t, (X == DYNAMIC_EXTENT ? DYNAMIC_EXTENT : sizeof(T) * X)> as_writable_bytes(span<T, X> s) noexcept
+template <typename T, uint64_t X, typename>
+inline span<uint8_t, (X == DYNAMIC_EXTENT ? DYNAMIC_EXTENT : sizeof(T) * X)> as_writable_bytes(span<T, X> s) noexcept
 {
     // NOLINTNEXTLINE(cppcoreguidelines-pro-type-reinterpret-cast)
     return {reinterpret_cast<uint8_t*>(s.data()), s.size_bytes()};
diff --git a/iceoryx_dust/vocabulary/include/iox/span.hpp b/iceoryx_dust/vocabulary/include/iox/span.hpp
index 99a26aa6d6..7c9521d0d5 100644
--- a/iceoryx_dust/vocabulary/include/iox/span.hpp
+++ b/iceoryx_dust/vocabulary/include/iox/span.hpp
@@ -193,8 +193,26 @@ struct span_storage<DYNAMIC_EXTENT>
         return m_size;
     }
 
+    span_storage(const span_storage& other) noexcept = default;
+    span_storage& operator=(const span_storage& other) noexcept = default;
+
+    span_storage(span_storage&& other) noexcept
+    {
+        *this = std::move(other);
+    }
+    span_storage& operator=(span_storage&& other) noexcept
+    {
+        if (this != &other)
+        {
+            m_size = other.m_size;
+            other.m_size = 0;
+        }
+        return *this;
+    }
+    ~span_storage() noexcept = default;
+
   private:
-    uint64_t m_size;
+    uint64_t m_size{0};
 };
 
 template <typename T>
@@ -319,10 +337,11 @@ class span : public detail::span_storage<Extent>
               typename = detail::enable_if_conversion_allowed_t<U, OtherExtent, T, Extent>>
     constexpr explicit span(const span<U, OtherExtent>& other);
 
-    constexpr span& operator=(const span& other) noexcept = default;
+    constexpr span& operator=(const span&) noexcept = default;
+
+    constexpr span(span&& other) noexcept;
+    constexpr span& operator=(span&& other) noexcept;
 
-    constexpr span(span&&) noexcept = delete;
-    span& operator=(span&&) noexcept = delete;
     ~span() noexcept = default;
 
     // subviews
@@ -419,6 +438,12 @@ class span : public detail::span_storage<Extent>
     T* m_data;
 };
 
+template <typename T, uint64_t X>
+span<const uint8_t, (X == DYNAMIC_EXTENT ? DYNAMIC_EXTENT : sizeof(T) * X)> as_bytes(span<T, X> s) noexcept;
+
+template <typename T, uint64_t X, typename = std::enable_if_t<!std::is_const<T>::value>>
+span<uint8_t, (X == DYNAMIC_EXTENT ? DYNAMIC_EXTENT : sizeof(T) * X)> as_writable_bytes(span<T, X> s) noexcept;
+
 } // namespace iox
 
 #include "iox/detail/span.inl"