kernel/fs: devfs: implement basic stat

2 files changed, 14 insertions, 1 deletions

diff --git a/kernel/kernel/filesystems/devfs/inode.cpp b/kernel/kernel/filesystems/devfs/inode.cpp
index e79a82e0..fb26e34e 100644
--- a/kernel/kernel/filesystems/devfs/inode.cpp
+++ b/kernel/kernel/filesystems/devfs/inode.cpp
@@ -2,6 +2,7 @@
 
 #include <kernel/vfs/device_number_registry.hpp>
 #include <kernel/vfs/error.hpp>
+#include <kernel/vfs/inode.hpp>
 
 #include <kapi/filesystem.hpp>
 
@@ -26,7 +27,8 @@ namespace kernel::filesystems::devfs
   namespace
   {
     constexpr auto static sentinel = kapi::filesystem::directory_cursor{std::numeric_limits<std::uint64_t>::max()};
-  }
+    constexpr auto static root_inode_number = std::numeric_limits<std::uint64_t>::max() - 1;
+  }  // namespace
 
   auto inode::read(std::span<std::byte>, kstd::bytes) const -> kstd::result<kstd::bytes>
   {
@@ -43,6 +45,15 @@ namespace kernel::filesystems::devfs
     return true;
   }
 
+  auto inode::status() const -> kstd::result<kapi::filesystem::file_status>
+  {
+    return vfs::inode::status().transform([](auto status) {
+      status.inode_number = root_inode_number;
+      status.mode = 0544;  // NOLINT(readability-magic-numbers)
+      return status;
+    });
+  }
+
   auto inode::read_directory(kapi::filesystem::directory_cursor position,
                              std::span<kapi::filesystem::directory_entry> entries) const
       -> kstd::result<std::pair<std::size_t, kapi::filesystem::directory_cursor>>
diff --git a/kernel/kernel/filesystems/devfs/inode.hpp b/kernel/kernel/filesystems/devfs/inode.hpp
index 61bec8cf..c19671df 100644
--- a/kernel/kernel/filesystems/devfs/inode.hpp
+++ b/kernel/kernel/filesystems/devfs/inode.hpp
@@ -26,6 +26,8 @@ namespace kernel::filesystems::devfs
 
     [[nodiscard]] auto is_directory() const -> bool override;
 
+    [[nodiscard]] auto status() const -> kstd::result<kapi::filesystem::file_status> override;
+
     [[nodiscard]] auto read_directory(kapi::filesystem::directory_cursor position,
                                       std::span<kapi::filesystem::directory_entry> entries) const
         -> kstd::result<std::pair<std::size_t, kapi::filesystem::directory_cursor>> override;