kapi/fs: implement read_directory

This change also replaces the kernel internal directory_listing_cursor
and directory_listing_entry with the kapi types directory_cursor and
directory_entry.

2 files changed, 11 insertions, 9 deletions

diff --git a/kernel/kapi/filesystem.cpp b/kernel/kapi/filesystem.cpp
index 7a0c2728..2f3c524e 100644
--- a/kernel/kapi/filesystem.cpp
+++ b/kernel/kapi/filesystem.cpp
@@ -4,7 +4,6 @@
 
 #include <kstd/memory.hpp>
 #include <kstd/result.hpp>
-#include <kstd/system_error.hpp>
 #include <kstd/units.hpp>
 
 #include <cstddef>
@@ -12,7 +11,6 @@
 #include <expected>
 #include <span>
 #include <string_view>
-#include <utility>
 
 namespace kapi::filesystem
 {
@@ -90,13 +88,11 @@ namespace kapi::filesystem
     return kernel::vfs::vfs::get().create_device_node(path, static_cast<std::uint32_t>(type), number);
   }
 
-  auto read_directory(std::size_t file_descriptor, directory_cursor position, std::span<directory_entry> buffer)
-      -> kstd::result<std::pair<std::size_t, directory_cursor>>
+  auto read_directory(std::size_t file_descriptor, std::span<directory_entry> buffer) -> kstd::result<std::size_t>
   {
-    static_cast<void>(file_descriptor);
-    static_cast<void>(position);
-    static_cast<void>(buffer);
-    return kstd::failure(make_error_code(kstd::errc::not_supported));
+    return kernel::vfs::open_file_table::get().file(file_descriptor).and_then([=](auto file) {
+      return file->read_directory(buffer);
+    });
   }
 
 }  // namespace kapi::filesystem
\ No newline at end of file
diff --git a/kernel/kapi/filesystem.tests.cpp b/kernel/kapi/filesystem.tests.cpp
index b2e39967..6fa2de3d 100644
--- a/kernel/kapi/filesystem.tests.cpp
+++ b/kernel/kapi/filesystem.tests.cpp
@@ -11,6 +11,7 @@
 #include <bit>
 #include <cstddef>
 #include <filesystem>
+#include <ranges>
 #include <string_view>
 #include <vector>
 
@@ -299,7 +300,12 @@ SCENARIO_METHOD(kernel::tests::vfs::storage_boot_module_vfs_fixture, "Kapi files
       REQUIRE(directory);
 
       auto buffer = std::vector<kapi::filesystem::directory_entry>{10};
-      REQUIRE_FALSE(kapi::filesystem::read_directory(*directory, {}, buffer));
+      REQUIRE(kapi::filesystem::read_directory(*directory, buffer) == 4);
+
+      REQUIRE(std::ranges::find(buffer, "info_1.txt", &kapi::filesystem::directory_entry::name) !=
+              std::ranges::end(buffer));
+      REQUIRE(std::ranges::find(buffer, "info_2.txt", &kapi::filesystem::directory_entry::name) !=
+              std::ranges::end(buffer));
     }
   }
 }