Kernel: remove message from BAN::Error

We don't store the error message anymore in BAN::Error.
Instead we store a error code that can be mapped into a string.
This allows BAN::Error to only take 4 bytes instead of 128.

We should also make some kernel initialization just panic instead
of returning errors since they are required for succesfull boot
anyway.

BAN/include/BAN/Errors.h

@@ -8,6 +8,7 @@
 
 #if defined(__is_kernel)
 	#include <kernel/Panic.h>
+	#include <kernel/Errors.h>
 	#define MUST(expr)	({ auto e = expr; if (e.is_error()) Kernel::panic("{}", e.error()); e.release_value(); })
 #else
 	#define MUST(expr)	({ auto e = expr; assert(!e.is_error()); e.release_value(); })
@@ -20,43 +21,38 @@ namespace BAN
 
 	class Error
 	{
+	private:
+		static constexpr uint32_t kernel_error_mask = 0x80000000;
+
 	public:
-		static Error from_c_string(const char* message)
+		static Error from_error_code(Kernel::ErrorCode error)
 		{
-			Error result;
+			return Error((uint32_t)error | kernel_error_mask);
-			strncpy(result.m_message, message, sizeof(Error::m_message));
-			result.m_message[sizeof(Error::m_message) - 1] = '\0';
-			result.m_error_code = 0xFF;
-			return result;
-		}
-		template<typename... Args>
-		static Error from_format(const char* format, Args&&... args)
-		{
-			char buffer[sizeof(Error::m_message)] {};
-			size_t index = 0;
-			auto putc = [&](char ch)
-			{
-				if (index < sizeof(buffer) - 1)
-					buffer[index++] = ch;
-			};
-			Formatter::print(putc, format, forward<Args>(args)...);
-			return from_c_string(buffer);
 		}
 		static Error from_errno(int error)
 		{
-			Error result;
+			return Error(error);
-			strncpy(result.m_message, strerror(error), sizeof(Error::m_message));
-			result.m_message[sizeof(Error::m_message) - 1] = '\0';
-			result.m_error_code = error;
-			return result;
 		}
 
-		uint8_t get_error_code() const { return m_error_code; }
+		Kernel::ErrorCode kernel_error() const
-		const char* get_message() const { return m_message; }
+		{
+			return (Kernel::ErrorCode)(m_error_code & ~kernel_error_mask);
+		}
+
+		uint32_t get_error_code() const { return m_error_code; }
+		BAN::StringView get_message() const
+		{
+			if (m_error_code & kernel_error_mask)
+				return Kernel::error_string(kernel_error());
+			return strerror(m_error_code);
+		}
 
 	private:
-		char m_message[128];
+		Error(uint32_t error)
-		uint8_t m_error_code;
+			: m_error_code(error)
+		{}
+
+		uint32_t m_error_code;
 	};
 
 	template<typename T>
@@ -82,7 +78,7 @@ namespace BAN
 		const T& value() const			{ return m_data.template get<T>(); }
 		T& value()						{ return m_data.template get<T>(); }
 
-		Error release_error()				{ return move(error()); m_data.clear(); }
+		Error release_error()			{ return move(error()); m_data.clear(); }
 		T release_value()				{ return move(value()); m_data.clear(); }
 
 	private:
@@ -102,12 +98,12 @@ namespace BAN
 		const Error& error() const		{ return m_data; }
 		void value()					{ }
 
-		Error release_error()			{ return move(m_data); m_data = Error(); }
+		Error release_error()			{ return move(m_data); }
-		void release_value()			{ m_data = Error(); }
+		void release_value()			{ }
 
 	private:
-		Error m_data;
+		Error m_data { Error::from_error_code(Kernel::ErrorCode::None) };
-		bool m_has_error = false;
+		bool m_has_error { false };
 	};
 
 }
@@ -115,11 +111,8 @@ namespace BAN
 namespace BAN::Formatter
 {
 	template<typename F>
-	void print_argument(F putc, const Error& error, const ValueFormat&)
+	void print_argument(F putc, const Error& error, const ValueFormat& format)
 	{
-		if (error.get_error_code() == 0xFF)
+		print_argument(putc, error.get_message(), format);
-			print(putc, error.get_message());
-		else
-			print(putc, "{} ({})", error.get_message(), error.get_error_code());
 	}
 }

kernel/CMakeLists.txt

@@ -17,6 +17,7 @@ set(KERNEL_SOURCES
 	kernel/Debug.cpp
 	kernel/Device.cpp
 	kernel/DeviceManager.cpp
+	kernel/Errors.cpp
 	kernel/Font.cpp
 	kernel/FS/Ext2.cpp
 	kernel/FS/VirtualFileSystem.cpp

kernel/include/kernel/Errors.h

@@ -0,0 +1,39 @@
+#pragma once
+
+#include <BAN/StringView.h>
+
+namespace Kernel
+{
+
+	enum class ErrorCode : uint32_t
+	{
+		None,
+		ACPI_NoRootSDT,
+		ACPI_NoSuchHeader,
+		ACPI_RootInvalid,
+		PS2_Timeout,
+		PS2_SelfTest,
+		PS2_Reset,
+		PS2_UnsupportedDevice,
+		Ext2_Invalid,
+		Ext2_Corrupted,
+		Ext2_NoInodes,
+		Storage_Boundaries,
+		Storage_GPTHeader,
+		ATA_NoLBA,
+		ATA_AMNF,
+		ATA_TKZNF,
+		ATA_ABRT,
+		ATA_MCR,
+		ATA_IDNF,
+		ATA_MC,
+		ATA_UNC,
+		ATA_BBK,
+		Font_FileTooSmall,
+		Font_Unsupported,
+		Count
+	};
+
+	BAN::StringView error_string(ErrorCode);
+
+}

kernel/kernel/ACPI.cpp

@@ -100,7 +100,7 @@ namespace Kernel
 	{
 		const RSDP* rsdp = locate_rsdp();
 		if (rsdp == nullptr)
-			return BAN::Error::from_c_string("Could not find RSDP");
+			return BAN::Error::from_error_code(ErrorCode::ACPI_NoRootSDT);
 
 		if (rsdp->revision >= 2)
 		{
@@ -109,9 +109,9 @@ namespace Kernel
 			BAN::ScopeGuard _([xsdt] { MMU::get().unallocate_page((uintptr_t)xsdt); });
 
 			if (memcmp(xsdt->signature, "XSDT", 4) != 0)
-				return BAN::Error::from_c_string("XSDT has invalid signature");
+				return BAN::Error::from_error_code(ErrorCode::ACPI_RootInvalid);
 			if (!is_valid_std_header(xsdt))
-				return BAN::Error::from_c_string("XSDT has invalid checksum");
+				return BAN::Error::from_error_code(ErrorCode::ACPI_RootInvalid);
 
 			m_header_table = (uintptr_t)xsdt->entries;
 			m_entry_size = 8;
@@ -124,9 +124,9 @@ namespace Kernel
 			BAN::ScopeGuard _([rsdt] { MMU::get().unallocate_page((uintptr_t)rsdt); });
 
 			if (memcmp(rsdt->signature, "RSDT", 4) != 0)
-				return BAN::Error::from_c_string("RSDT has invalid signature");
+				return BAN::Error::from_error_code(ErrorCode::ACPI_RootInvalid);
 			if (!is_valid_std_header(rsdt))
-				return BAN::Error::from_c_string("RSDT has invalid checksum");
+				return BAN::Error::from_error_code(ErrorCode::ACPI_RootInvalid);
 
 			m_header_table = (uintptr_t)rsdt->entries;
 			m_entry_size = 4;
@@ -148,7 +148,7 @@ namespace Kernel
 				return header;
 			unmap_header(header);
 		}
-		return BAN::Error::from_format("Could not find ACPI header '{}'", BAN::StringView(signature, 4));
+		return BAN::Error::from_error_code(ErrorCode::ACPI_NoSuchHeader);
 	}
 
 	void ACPI::unmap_header(const ACPI::SDTHeader* header)

kernel/kernel/Errors.cpp

@@ -0,0 +1,40 @@
+#include <kernel/Errors.h>
+
+namespace Kernel
+{
+
+	static BAN::StringView s_error_strings[] {
+		"No Error"sv,
+		"ACPI could not find root SDT header"sv,
+		"ACPI no such header"sv,
+		"ACPI root invalid",
+		"PS/2 device timeout"sv,
+		"PS/2 controller self test failed"sv,
+		"PS/2 reset failed"sv,
+		"PS/2 unsupported device"sv,
+		"Invalid ext2 filesystem"sv,
+		"Ext2 filesystem corrupted"sv,
+		"Ext2 filesystem out of inodes"sv,
+		"Attempted to access outside of device boundaries"sv,
+		"Device has invalid GPT header"sv,
+		"Device does not support LBA addressing"sv,
+		"Address mark not found"sv,
+		"Track zero not found"sv,
+		"Aborted command"sv,
+		"Media change request"sv,
+		"ID not found"sv,
+		"Media changed"sv,
+		"Uncorrectable data error"sv,
+		"Bad Block detected"sv,
+		"Font file too small"sv,
+		"Unsupported font format"sv,
+	};
+	static_assert(sizeof(s_error_strings) / sizeof(*s_error_strings) == (size_t)ErrorCode::Count);
+
+	BAN::StringView error_string(ErrorCode error)
+	{
+		ASSERT((uint32_t)error < (uint32_t)ErrorCode::Count);
+		return s_error_strings[(uint32_t)error];
+	}
+
+}

kernel/kernel/FS/Ext2.cpp

@@ -463,7 +463,7 @@ namespace Kernel
 		}
 
 		if (m_superblock.magic != 0xEF53)
-			return BAN::Error::from_c_string("Not an ext2 filesystem");
+			return BAN::Error::from_error_code(ErrorCode::Ext2_Invalid);
 
 		if (m_superblock.rev_level < 1)
 		{
@@ -475,7 +475,7 @@ namespace Kernel
 		uint32_t number_of_block_groups       = BAN::Math::div_round_up(superblock().inodes_count, superblock().inodes_per_group);
 		uint32_t number_of_block_groups_check = BAN::Math::div_round_up(superblock().blocks_count, superblock().blocks_per_group);
 		if (number_of_block_groups != number_of_block_groups_check)
-			return BAN::Error::from_c_string("Ambiguous number of block groups");
+			return BAN::Error::from_error_code(ErrorCode::Ext2_Corrupted);
 
 		ASSERT(!(m_superblock.feature_incompat & Ext2::Enum::FEATURE_INCOMPAT_COMPRESSION));
 		//ASSERT(!(m_superblock.feature_incompat & Ext2::Enum::FEATURE_INCOMPAT_FILETYPE));
@@ -546,7 +546,7 @@ namespace Kernel
 			}
 		}
 
-		return BAN::Error::from_c_string("No free inodes available in the whole filesystem");
+		return BAN::Error::from_error_code(ErrorCode::Ext2_NoInodes);
 	}
 
 	void Ext2FS::read_block(uint32_t block, BAN::Span<uint8_t> buffer)

kernel/kernel/FS/VirtualFileSystem.cpp

@@ -18,8 +18,7 @@ namespace Kernel
 			return BAN::Error::from_errno(ENOMEM);
 		BAN::ScopeGuard guard([] { delete s_instance; s_instance = nullptr; } );
 
-		if (root.size() < 5 || root.substring(0, 5) != "/dev/")
+		ASSERT(root.size() >= 5 && root.substring(0, 5) == "/dev/"sv);;
-			return BAN::Error::from_c_string("root must be in /dev/");
 		root = root.substring(5);
 
 		auto partition_inode = TRY(DeviceManager::get().read_directory_inode(root));
@@ -43,11 +42,11 @@ namespace Kernel
 	{
 		auto partition_file = TRY(file_from_absolute_path(partition));
 		if (partition_file.inode->inode_type() != Inode::InodeType::Device)
-			return BAN::Error::from_c_string("Not a partition");
+			return BAN::Error::from_errno(ENOTBLK);
 
 		Device* device = (Device*)partition_file.inode.ptr();
-		if (device->device_type() != Device::DeviceType::Partition)
+		if (device->device_type() != Device::DeviceType::BlockDevice)
-			return BAN::Error::from_c_string("Not a partition");
+			return BAN::Error::from_errno(ENOTBLK);
 
 		auto* file_system = TRY(Ext2FS::create(*(Partition*)device));
 		return mount(file_system, target);
@@ -90,8 +89,7 @@ namespace Kernel
 		ASSERT(path.front() == '/');
 
 		auto inode = root_inode();
-		if (!inode)
+		ASSERT(inode);
-			return BAN::Error::from_c_string("No root inode available");
 
 		BAN::String canonical_path;
 

kernel/kernel/Font.cpp

@@ -48,7 +48,7 @@ namespace Kernel
 		TRY(Process::current()->read(fd, file_data.data(), st.st_size));
 
 		if (file_data.size() < 4)
-			return BAN::Error::from_c_string("Font file is too small");
+			return BAN::Error::from_error_code(ErrorCode::Font_FileTooSmall);
 
 		if (file_data[0] == PSF1_MAGIC0 && file_data[1] == PSF1_MAGIC1)
 			return TRY(parse_psf1(file_data.span()));
@@ -56,13 +56,13 @@ namespace Kernel
 		if (file_data[0] == PSF2_MAGIC0 && file_data[1] == PSF2_MAGIC1 && file_data[2] == PSF2_MAGIC2 && file_data[3] == PSF2_MAGIC3)
 			return TRY(parse_psf2(file_data.span()));
 
-		return BAN::Error::from_c_string("Unsupported font format");
+		return BAN::Error::from_error_code(ErrorCode::Font_Unsupported);
 	}
 
 	BAN::ErrorOr<Font> Font::parse_psf1(BAN::Span<const uint8_t> font_data)
 	{
 		if (font_data.size() < 4)
-			return BAN::Error::from_c_string("Font file is too small");
+			return BAN::Error::from_error_code(ErrorCode::Font_FileTooSmall);
 
 		struct PSF1Header
 		{
@@ -77,7 +77,7 @@ namespace Kernel
 		uint32_t glyph_data_size = glyph_size * glyph_count;
 
 		if (font_data.size() < sizeof(PSF1Header) + glyph_data_size)
-			return BAN::Error::from_c_string("Font file is too small");
+			return BAN::Error::from_error_code(ErrorCode::Font_FileTooSmall);
 
 		BAN::Vector<uint8_t> glyph_data;
 		TRY(glyph_data.resize(glyph_data_size));
@@ -155,14 +155,14 @@ namespace Kernel
 		};
 
 		if (font_data.size() < sizeof(PSF2Header))
-			return BAN::Error::from_c_string("Font file is too small");
+			return BAN::Error::from_error_code(ErrorCode::Font_FileTooSmall);
 
 		const PSF2Header& header = *(const PSF2Header*)font_data.data();
 
 		uint32_t glyph_data_size = header.glyph_count * header.glyph_size;
 
 		if (font_data.size() < glyph_data_size + header.header_size)
-			return BAN::Error::from_c_string("Font file is too small");
+			return BAN::Error::from_error_code(ErrorCode::Font_FileTooSmall);
 
 		BAN::Vector<uint8_t> glyph_data;
 		TRY(glyph_data.resize(glyph_data_size));

kernel/kernel/Input/PS2Controller.cpp

@@ -116,7 +116,7 @@ namespace Kernel::Input
 				return {};
 			}
 		}
-		return BAN::Error::from_c_string("PS/2 device timeout");
+		return BAN::Error::from_error_code(ErrorCode::PS2_Timeout);
 	}
 
 	static BAN::ErrorOr<uint8_t> device_read_byte()
@@ -125,7 +125,7 @@ namespace Kernel::Input
 		while (PIT::ms_since_boot() < timeout)
 			if (IO::inb(PS2::IOPort::STATUS) & PS2::Status::OUTPUT_FULL)
 				return IO::inb(PS2::IOPort::DATA);
-		return BAN::Error::from_c_string("PS/2 device timeout");
+		return BAN::Error::from_error_code(ErrorCode::PS2_Timeout);
 	}
 
 	static BAN::ErrorOr<void> device_wait_ack()
@@ -175,15 +175,7 @@ namespace Kernel::Input
 		// FIXME
 
 		// Step 2: Determine if the PS/2 Controller Exists
-		if (false)
+		// FIXME
-		{
-			const ACPI::FADT* fadt = (const ACPI::FADT*)TRY(ACPI::get().get_header("FACP"));
-			bool ps2_exists = fadt->iapc_boot_arch & (1 << 1);
-			ACPI::get().unmap_header(fadt);
-
-			if (!ps2_exists)
-				return BAN::Error::from_c_string("PS2 Controller does not exist");
-		}
 
 		// Step 3: Disable Devices
 		controller_send_command(PS2::Command::DISABLE_FIRST_PORT);
@@ -203,7 +195,7 @@ namespace Kernel::Input
 		// Step 6: Perform Controller Self Test
 		controller_send_command(PS2::Command::TEST_CONTROLLER);
 		if (wait_and_read() != PS2::Response::TEST_CONTROLLER_PASS)
-			return BAN::Error::from_c_string("PS/2 Controller self test failed");
+			return BAN::Error::from_error_code(ErrorCode::PS2_SelfTest);
 		// NOTE: self test might reset the device so we set the config byte again
 		controller_send_command(PS2::Command::WRITE_CONFIG, config);
 
@@ -229,7 +221,7 @@ namespace Kernel::Input
 				valid_ports[1] = false;
 		}
 		if (!valid_ports[0] && !valid_ports[1])
-			return BAN::Error::from_c_string("No ports available on Controller");
+			return {};
 		
 		// Step 9: Enable Devices (and disable scanning)
 		for (uint8_t device = 0; device < 2; device++)
@@ -298,7 +290,7 @@ namespace Kernel::Input
 
 		// Standard PS/2 Mouse
 		if (index == 1 && (bytes[0] == 0x00))
-			return BAN::Error::from_c_string("PS/2 mouse not supported");
+			return BAN::Error::from_error_code(ErrorCode::PS2_UnsupportedDevice);
 		
 		// MF2 Keyboard
 		if (index == 2 && (bytes[0] == 0xAB && bytes[1] == 0x83))
@@ -306,7 +298,8 @@ namespace Kernel::Input
 
 		if (m_devices[device])
 			return {};
-		return BAN::Error::from_format("Unhandled PS/2 device {}{} ({} bytes)", bytes[0], bytes[1], index);
+
+		return BAN::Error::from_error_code(ErrorCode::PS2_UnsupportedDevice);
 	}
 
 	void PS2Controller::send_byte(const PS2Device* device, uint8_t byte)
@@ -321,7 +314,7 @@ namespace Kernel::Input
 		TRY(device_send_byte(device, PS2::DeviceCommand::RESET));
 		TRY(device_wait_ack());
 		if (TRY(device_read_byte()) != PS2::Response::SELF_TEST_PASS)
-			return BAN::Error::from_c_string("Device reset failed");
+			return BAN::Error::from_error_code(ErrorCode::PS2_Reset);
 		return {};
 	}
 

kernel/kernel/Process.cpp

@@ -64,8 +64,7 @@ namespace Kernel
 
 	BAN::ErrorOr<void> Process::init_stdio()
 	{
-		if (!m_open_files.empty())
+		ASSERT(m_open_files.empty());
-			return BAN::Error::from_c_string("Could not init stdio, process already has open files");
 		TRY(open("/dev/tty1", O_RDONLY)); // stdin
 		TRY(open("/dev/tty1", O_WRONLY)); // stdout
 		TRY(open("/dev/tty1", O_WRONLY)); // stderr
@@ -152,13 +151,17 @@ namespace Kernel
 	BAN::ErrorOr<void> Process::creat(BAN::StringView path, mode_t mode)
 	{
 		auto absolute_path = TRY(absolute_path_of(path));
-		while (absolute_path.back() != '/')
+
-			absolute_path.pop_back();
+		size_t index;
-		
+		for (index = absolute_path.size(); index > 0; index--)
-		auto parent_file = TRY(VirtualFileSystem::get().file_from_absolute_path(absolute_path));
+			if (absolute_path[index - 1] == '/')
-		if (path.count('/') > 0)
+				break;
-			return BAN::Error::from_c_string("You can only create files to current working directory");
+
-		TRY(parent_file.inode->create_file(path, mode));
+		auto directory = absolute_path.sv().substring(0, index);
+		auto file_name = absolute_path.sv().substring(index);
+
+		auto parent_file = TRY(VirtualFileSystem::get().file_from_absolute_path(directory));
+		TRY(parent_file.inode->create_file(file_name, mode));
 
 		return {};
 	}

kernel/kernel/Shell.cpp

@@ -327,11 +327,26 @@ argument_done:
 		if (arguments.empty())
 		{
 
+		}
+		else if (arguments.front() == "oof")
+		{
+			SpinLock lock;
+			for (int i = 0; i < 100; i++)
+			{
+				lock.lock();
+				MUST(Process::create_kernel([](void*) { MUST(Process::current()->init_stdio()); TTY_PRINTLN("####"); Process::current()->exit(); }, nullptr));
+				PIT::sleep(5);
+				kmalloc_dump_info();
+				lock.unlock();
+			}
 		}
 		else if (arguments.front() == "date")
 		{
 			if (arguments.size() != 1)
-				return BAN::Error::from_c_string("'date' does not support command line arguments");
+			{
+				TTY_PRINTLN("'date' does not support command line arguments");
+				return {};
+			}
 			auto time = RTC::get_current_time();
 			TTY_PRINTLN("{}", time);
 		}
@@ -348,7 +363,10 @@ argument_done:
 		else if (arguments.front() == "clear")
 		{
 			if (arguments.size() != 1)
-				return BAN::Error::from_c_string("'clear' does not support command line arguments");
+			{
+				TTY_PRINTLN("'clear' does not support command line arguments");
+				return {};
+			}
 			TTY_PRINT("\e[2J\e[H");
 		}
 		else if (arguments.front() == "time")
@@ -382,8 +400,7 @@ argument_done:
 				PIT::sleep(5000);
 
 				if (auto res = shell->process_command(args); res.is_error())
-					dprintln("{}", res.error());
+					TTY_PRINT("{}", res.error());
-					//BAN::Formatter::println([&](char c) { shell->m_tty->putchar(c); }, "{}", res.error());
 			};
 
 			SpinLock spinlock;
@@ -395,19 +412,28 @@ argument_done:
 		else if (arguments.front() == "memory")
 		{
 			if (arguments.size() != 1)
-				return BAN::Error::from_c_string("'memory' does not support command line arguments");
+			{
+				TTY_PRINTLN("'memory' does not support command line arguments");
+				return {};
+			}
 			kmalloc_dump_info();
 		}
 		else if (arguments.front() == "sleep")
 		{
 			if (arguments.size() != 1)
-				return BAN::Error::from_c_string("'sleep' does not support command line arguments");
+			{
+				TTY_PRINTLN("'sleep' does not support command line arguments");
+				return {};
+			}
 			PIT::sleep(5000);
 		}
 		else if (arguments.front() == "cpuinfo")
 		{
 			if (arguments.size() != 1)
-				return BAN::Error::from_c_string("'cpuinfo' does not support command line arguments");
+			{
+				TTY_PRINTLN("'cpuinfo' does not support command line arguments");
+				return {};
+			}
 
 			uint32_t ecx, edx;
 			auto vendor = CPUID::get_vendor();
@@ -428,11 +454,17 @@ argument_done:
 		else if (arguments.front() == "random")
 		{
 			if (arguments.size() != 1)
-				return BAN::Error::from_c_string("'random' does not support command line arguments");
+			{
+				TTY_PRINTLN("'random' does not support command line arguments");
+				return {};
+			}
 			uint32_t ecx, edx;
 			CPUID::get_features(ecx, edx);
 			if (!(ecx & CPUID::Features::ECX_RDRND))
-				return BAN::Error::from_c_string("cpu does not support RDRAND instruction");
+			{
+				TTY_PRINTLN("cpu does not support RDRAND instruction");
+				return {};
+			}
 
 			for (int i = 0; i < 10; i++)
 			{
@@ -444,7 +476,10 @@ argument_done:
 		else if (arguments.front() == "reboot")
 		{
 			if (arguments.size() != 1)
-				return BAN::Error::from_c_string("'reboot' does not support command line arguments");
+			{
+				TTY_PRINTLN("'reboot' does not support command line arguments");
+				return {};
+			}
 			uint8_t good = 0x02;
 			while (good & 0x02)
 				good = IO::inb(0x64);
@@ -454,14 +489,20 @@ argument_done:
 		else if (arguments.front() == "lspci")
 		{
 			if (arguments.size() != 1)
-				return BAN::Error::from_c_string("'lspci' does not support command line arguments");
+			{
+				TTY_PRINTLN("'lspci' does not support command line arguments");
+				return {};
+			}
 			for (auto& device : PCI::get().devices())
 				TTY_PRINTLN("{2H}:{2H}.{2H} {2H}", device.bus(), device.dev(), device.func(), device.class_code());
 		}
 		else if (arguments.front() == "ls")
 		{
 			if (arguments.size() > 2)
-				return BAN::Error::from_c_string("usage: 'ls [path]'");
+			{
+				TTY_PRINTLN("usage: 'ls [path]'");
+				return {};
+			}
 
 			BAN::String path;
 			if (arguments.size() == 2)
@@ -508,7 +549,10 @@ argument_done:
 		else if (arguments.front() == "cat")
 		{
 			if (arguments.size() != 2)
-				return BAN::Error::from_c_string("usage: 'cat path'");
+			{
+				TTY_PRINTLN("usage: 'cat path'");
+				return {};
+			}
 			
 			int fd = TRY(Process::current()->open(arguments[1], O_RDONLY));
 			BAN::ScopeGuard _([fd] { MUST(Process::current()->close(fd)); });
@@ -521,7 +565,10 @@ argument_done:
 		else if (arguments.front() == "stat")
 		{
 			if (arguments.size() != 2)
-				return BAN::Error::from_c_string("usage: 'stat path'");
+			{
+				TTY_PRINTLN("usage: 'stat path'");
+				return {};
+			}
 			
 			stat st;
 			TRY(Process::current()->stat(arguments[1], &st));
@@ -549,7 +596,10 @@ argument_done:
 		else if (arguments.front() == "cd")
 		{
 			if (arguments.size() > 2)
-				return BAN::Error::from_c_string("usage 'cd path'");
+			{
+				TTY_PRINTLN("usage 'cd path'");
+				return {};
+			}
 			BAN::StringView path = arguments.size() == 2 ? arguments[1].sv() : "/"sv;
 			TRY(Process::current()->set_working_directory(path));
 			TRY(update_prompt());
@@ -557,13 +607,19 @@ argument_done:
 		else if (arguments.front() == "touch")
 		{
 			if (arguments.size() != 2)
-				return BAN::Error::from_c_string("usage 'touch path'");
+			{
+				TTY_PRINTLN("usage 'touch path'");
+				return {};
+			}
 			TRY(Process::current()->creat(arguments[1], 0));
 		}
 		else if (arguments.front() == "cksum")
 		{
 			if (arguments.size() < 2)
-				return BAN::Error::from_c_string("usage 'cksum paths...'");
+			{
+				TTY_PRINTLN("usage 'cksum paths...'");
+				return {};
+			}
 
 			uint8_t buffer[1024];
 			for (size_t i = 1; i < arguments.size(); i++)
@@ -594,20 +650,27 @@ argument_done:
 		else if (arguments.front() == "mount")
 		{
 			if (arguments.size() != 3)
-				return BAN::Error::from_c_string("usage: 'mount partition directory'");
+			{
+				TTY_PRINTLN("usage: 'mount partition directory'");
+				return {};
+			}
 			TRY(Process::current()->mount(arguments[1], arguments[2]));
 		}
 		else if (arguments.front() == "loadfont")
 		{
 			if (arguments.size() != 2)
-				return BAN::Error::from_c_string("usage: 'loadfont font_path'");
+			{
+				TTY_PRINTLN("usage: 'loadfont font_path'");
+				return {};
+			}
 
 			auto font = TRY(Font::load(arguments[1]));
 			//m_tty->set_font(font);
 		}
 		else
 		{
-			return BAN::Error::from_format("unrecognized command '{}'", arguments.front());
+			TTY_PRINTLN("unrecognized command '{}'", arguments.front());
+			return {};
 		}
 
 		return {};

kernel/kernel/Storage/ATABus.cpp

@@ -224,22 +224,23 @@ namespace Kernel
 	{
 		uint8_t err = io_read(ATA_PORT_ERROR);
 		if (err & ATA_ERROR_AMNF)
-			return BAN::Error::from_c_string("Address mark not found.");
+			return BAN::Error::from_error_code(ErrorCode::ATA_AMNF);
 		if (err & ATA_ERROR_TKZNF)
-			return BAN::Error::from_c_string("Track zero not found.");
+			return BAN::Error::from_error_code(ErrorCode::ATA_TKZNF);
 		if (err & ATA_ERROR_ABRT)
-			return BAN::Error::from_c_string("Aborted command.");
+			return BAN::Error::from_error_code(ErrorCode::ATA_ABRT);
 		if (err & ATA_ERROR_MCR)
-			return BAN::Error::from_c_string("Media change request.");
+			return BAN::Error::from_error_code(ErrorCode::ATA_MCR);
 		if (err & ATA_ERROR_IDNF)
-			return BAN::Error::from_c_string("ID not found.");
+			return BAN::Error::from_error_code(ErrorCode::ATA_IDNF);
 		if (err & ATA_ERROR_MC)
-			return BAN::Error::from_c_string("Media changed.");
+			return BAN::Error::from_error_code(ErrorCode::ATA_MC);
 		if (err & ATA_ERROR_UNC)
-			return BAN::Error::from_c_string("Uncorrectable data error.");
+			return BAN::Error::from_error_code(ErrorCode::ATA_UNC);
 		if (err & ATA_ERROR_BBK)
-			return BAN::Error::from_c_string("Bad Block detected.");
+			return BAN::Error::from_error_code(ErrorCode::ATA_BBK);
-		return BAN::Error::from_c_string("No error");
+		
+		return BAN::Error::from_error_code(ErrorCode::None);
 	}
 
 	uint8_t ATABus::device_index(const ATADevice* device) const
@@ -251,7 +252,7 @@ namespace Kernel
 	BAN::ErrorOr<void> ATABus::read(ATADevice* device, uint64_t lba, uint8_t sector_count, uint8_t* buffer)
 	{
 		if (lba + sector_count > device->m_lba_count)
-			return BAN::Error::from_c_string("Attempted to read outside of the device boundaries");
+			return BAN::Error::from_error_code(ErrorCode::Storage_Boundaries);
 
 		LockGuard _(m_lock);
 
@@ -285,7 +286,7 @@ namespace Kernel
 	BAN::ErrorOr<void> ATABus::write(ATADevice* device, uint64_t lba, uint8_t sector_count, const uint8_t* buffer)
 	{
 		if (lba + sector_count > device->m_lba_count)
-			return BAN::Error::from_c_string("Attempted to write outside of the device boundaries");
+			return BAN::Error::from_error_code(ErrorCode::Storage_Boundaries);
 
 		LockGuard _(m_lock);
 

kernel/kernel/Storage/ATADevice.cpp

@@ -18,7 +18,7 @@ namespace Kernel
 		m_command_set |= (uint32_t)(identify_buffer[ATA_IDENTIFY_COMMAND_SET + 1] << 16);
 
 		if (!(m_capabilities & ATA_CAPABILITIES_LBA))
-			return BAN::Error::from_c_string("Device does not support LBA addressing");
+			return BAN::Error::from_error_code(ErrorCode::ATA_NoLBA);
 		
 		if ((identify_buffer[ATA_IDENTIFY_SECTOR_INFO] & (1 << 15)) == 0 &&
 			(identify_buffer[ATA_IDENTIFY_SECTOR_INFO] & (1 << 14)) != 0 &&

kernel/kernel/Storage/StorageDevice.cpp

@@ -147,28 +147,28 @@ namespace Kernel
 	BAN::ErrorOr<void> StorageDevice::initialize_partitions()
 	{
 		if (total_size() < sizeof(GPTHeader))
-			return BAN::Error::from_format("Disk {} does not have enough space for GPT header", name());
+			return BAN::Error::from_error_code(ErrorCode::Storage_GPTHeader);
 
 		BAN::Vector<uint8_t> lba1(sector_size());
 		TRY(read_sectors(1, 1, lba1.data()));
 
 		const GPTHeader& header = *(const GPTHeader*)lba1.data();
 		if (!is_valid_gpt_header(header, sector_size()))
-			return BAN::Error::from_format("Disk {} has invalid GPT header", name());
+			return BAN::Error::from_error_code(ErrorCode::Storage_GPTHeader);
 
 		uint32_t size = header.partition_entry_count * header.partition_entry_size;
 		if (uint32_t remainder = size % sector_size())
 			size += sector_size() - remainder;
 
 		if (total_size() < header.partition_entry_lba * sector_size() + size)
-			return BAN::Error::from_format("Disk {} has invalid GPT header", name());
+			return BAN::Error::from_error_code(ErrorCode::Storage_GPTHeader);
 
 		BAN::Vector<uint8_t> entry_array;
 		TRY(entry_array.resize(size));
 		TRY(read_sectors(header.partition_entry_lba, size / sector_size(), entry_array.data()));
 
 		if (!is_valid_gpt_crc32(header, lba1, entry_array))
-			return BAN::Error::from_format("Disk {} has invalid crc3 in the GPT header", name());
+			return BAN::Error::from_error_code(ErrorCode::Storage_GPTHeader);
 
 		for (uint32_t i = 0; i < header.partition_entry_count; i++)
 		{
@@ -220,7 +220,7 @@ namespace Kernel
 	{
 		const uint32_t sectors_in_partition = m_lba_end - m_lba_start;
 		if (lba + sector_count > sectors_in_partition)
-			return BAN::Error::from_c_string("Attempted to read outside of the partition boundaries");
+			return BAN::Error::from_error_code(ErrorCode::Storage_Boundaries);
 		TRY(m_device.read_sectors(m_lba_start + lba, sector_count, buffer));
 		return {};
 	}
@@ -229,7 +229,7 @@ namespace Kernel
 	{
 		const uint32_t sectors_in_partition = m_lba_end - m_lba_start;
 		if (lba + sector_count > sectors_in_partition)
-			return BAN::Error::from_c_string("Attempted to write outside of the partition boundaries");
+			return BAN::Error::from_error_code(ErrorCode::Storage_Boundaries);
 		TRY(m_device.write_sectors(m_lba_start + lba, sector_count, buffer));
 		return {};
 	}

libc/include/errno.h

@@ -15,6 +15,7 @@
 #define ENAMETOOLONG 11
 #define ENOBUFS 12
 #define ENOTTY 13
+#define ENOTBLK 14
 
 __BEGIN_DECLS
 

libc/string.cpp

@@ -122,6 +122,9 @@ char* strerror(int error)
 	case ENOTTY:
 		strcpy(buffer, "Inappropriate I/O control operation");
 		break;
+	case ENOTBLK:
+		strcpy(buffer, "Block device required");
+		break;
 	default:
 		{
 			// FIXME: sprintf