Merge branch 'fmorgner/stateless-fs-drivers' into 'develop'

kernel/fs: rework filesystem subsystem to use stateless drivers

See merge request teachos/kernel!56

1 files changed, 57 insertions, 0 deletions

diff --git a/libs/kstd/kstd/span.hpp b/libs/kstd/kstd/span.hpp
new file mode 100644
index 00000000..6be2eea2
--- /dev/null
+++ b/libs/kstd/kstd/span.hpp
@@ -0,0 +1,57 @@
+#ifndef KSTD_SPAN_HPP
+#define KSTD_SPAN_HPP
+
+#include <cstddef>
+#include <ranges>
+#include <span>  // IWYU pragma: export
+
+namespace kstd
+{
+
+  //! Get a read-only span of bytes, that maps to a given object
+  //!
+  //! @param object The object to obtain the byte span for.
+  //! @return A span over the raw bytes of the object representation of the given object.
+  template<typename ObjectType>
+    requires(!std::ranges::range<ObjectType>)
+  constexpr auto raw_bytes(ObjectType const & object) -> std::span<std::byte const, sizeof(ObjectType)>
+  {
+    return std::as_bytes(std::span<ObjectType const, 1>{std::addressof(object), 1});
+  }
+
+  //! Get a read-write span of bytes, that maps to a given object
+  //!
+  //! @param object The object to obtain the byte span for.
+  //! @return A span over the raw bytes of the object representation of the given object.
+  template<typename ObjectType>
+    requires(!std::ranges::range<ObjectType>)
+  constexpr auto raw_bytes(ObjectType & object) -> std::span<std::byte, sizeof(ObjectType)>
+  {
+    return std::as_writable_bytes(std::span<ObjectType, 1>{std::addressof(object), 1});
+  }
+
+  //! Get a read-only span of bytes, that maps to a given range object
+  //!
+  //! @param range The range of objects to obtain the byte span for.
+  //! @return A span over the raw bytes of the object representation of the given object.
+  template<typename ObjectType>
+    requires(std::ranges::range<ObjectType>)
+  constexpr auto raw_bytes(ObjectType const & range) -> std::span<std::byte const>
+  {
+    return std::as_bytes(std::span{range});
+  }
+
+  //! Get a read-write span of bytes, that maps to a given range object
+  //!
+  //! @param range The range of objects to obtain the byte span for.
+  //! @return A span over the raw bytes of the object representation of the given object.
+  template<typename ObjectType>
+    requires(std::ranges::range<ObjectType>)
+  constexpr auto raw_bytes(ObjectType & range) -> std::span<std::byte>
+  {
+    return std::as_writable_bytes(std::span{range});
+  }
+
+}  // namespace kstd
+
+#endif
\ No newline at end of file