Kernel: Implement TmpFS directory listing

kernel/kernel/FS/TmpFS/Inode.cpp

@@ -276,9 +276,51 @@ namespace Kernel
 		return BAN::RefPtr<Inode>(inode);
 	}
 
-	BAN::ErrorOr<void> TmpDirectoryInode::list_next_inodes_impl(off_t, DirectoryEntryList*, size_t)
+	BAN::ErrorOr<void> TmpDirectoryInode::list_next_inodes_impl(off_t data_block_index, DirectoryEntryList* list, size_t list_len)
 	{
-		return BAN::Error::from_errno(ENOTSUP);
+		if (list_len < (size_t)blksize())
+		{
+			dprintln("buffer is too small");
+			return BAN::Error::from_errno(ENOBUFS);
+		}
+
+		auto block_index = this->block_index(data_block_index);
+		
+		list->entry_count = 0;
+
+		// if we reach a non-allocated block, it marks the end
+		if (!block_index.has_value())
+			return {};
+		
+		auto* dirp = list->array;
+
+		const size_t byte_count = BAN::Math::min<size_t>(size() - data_block_index * blksize(), blksize());
+		m_fs.with_block_buffer(block_index.value(), [&](BAN::ByteSpan bytespan) {
+			bytespan = bytespan.slice(0, byte_count);
+
+			while (bytespan.size() > 0)
+			{
+				const auto& entry = bytespan.as<TmpDirectoryEntry>();
+
+				if (entry.type != DT_UNKNOWN)
+				{
+					// TODO: dirents should be aligned
+
+					dirp->dirent.d_ino = entry.ino;
+					dirp->dirent.d_type = entry.type;
+					strncpy(dirp->dirent.d_name, entry.name, entry.name_len);
+					dirp->dirent.d_name[entry.name_len] = '\0';
+					dirp->rec_len = sizeof(DirectoryEntry) + entry.name_len + 1;
+					dirp = dirp->next();
+
+					list->entry_count++;
+				}
+
+				bytespan = bytespan.slice(entry.rec_len);
+			}
+		});
+
+		return {};
 	}
 
 	BAN::ErrorOr<void> TmpDirectoryInode::create_file_impl(BAN::StringView name, mode_t mode, uid_t uid, gid_t gid)