// Copyright 2014 Citra Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#pragma once
#include <cassert>
#include <cstddef>
#include <type_traits>
#include <utility>
#include "common/bit_field.h"
#include "common/common_funcs.h"
#include "common/common_types.h"
// All the constants in this file come from http://3dbrew.org/wiki/Error_codes
/// Detailed description of the error. This listing is likely incomplete.
enum class ErrorDescription : u32 {
Success = 0,
FS_NotFound = 100,
FS_NotFormatted = 340, ///< This is used by the FS service when creating a SaveData archive
InvalidSection = 1000,
TooLarge = 1001,
NotAuthorized = 1002,
AlreadyDone = 1003,
InvalidSize = 1004,
InvalidEnumValue = 1005,
InvalidCombination = 1006,
NoData = 1007,
Busy = 1008,
MisalignedAddress = 1009,
MisalignedSize = 1010,
OutOfMemory = 1011,
NotImplemented = 1012,
InvalidAddress = 1013,
InvalidPointer = 1014,
InvalidHandle = 1015,
NotInitialized = 1016,
AlreadyInitialized = 1017,
NotFound = 1018,
CancelRequested = 1019,
AlreadyExists = 1020,
OutOfRange = 1021,
Timeout = 1022,
InvalidResultValue = 1023,
};
/**
* Identifies the module which caused the error. Error codes can be propagated through a call
* chain, meaning that this doesn't always correspond to the module where the API call made is
* contained.
*/
enum class ErrorModule : u32 {
Common = 0,
Kernel = 1,
Util = 2,
FileServer = 3,
LoaderServer = 4,
TCB = 5,
OS = 6,
DBG = 7,
DMNT = 8,
PDN = 9,
GX = 10,
I2C = 11,
GPIO = 12,
DD = 13,
CODEC = 14,
SPI = 15,
PXI = 16,
FS = 17,
DI = 18,
HID = 19,
CAM = 20,
PI = 21,
PM = 22,
PM_LOW = 23,
FSI = 24,
SRV = 25,
NDM = 26,
NWM = 27,
SOC = 28,
LDR = 29,
ACC = 30,
RomFS = 31,
AM = 32,
HIO = 33,
Updater = 34,
MIC = 35,
FND = 36,
MP = 37,
MPWL = 38,
AC = 39,
HTTP = 40,
DSP = 41,
SND = 42,
DLP = 43,
HIO_LOW = 44,
CSND = 45,
SSL = 46,
AM_LOW = 47,
NEX = 48,
Friends = 49,
RDT = 50,
Applet = 51,
NIM = 52,
PTM = 53,
MIDI = 54,
MC = 55,
SWC = 56,
FatFS = 57,
NGC = 58,
CARD = 59,
CARDNOR = 60,
SDMC = 61,
BOSS = 62,
DBM = 63,
Config = 64,
PS = 65,
CEC = 66,
IR = 67,
UDS = 68,
PL = 69,
CUP = 70,
Gyroscope = 71,
MCU = 72,
NS = 73,
News = 74,
RO_1 = 75,
GD = 76,
CardSPI = 77,
EC = 78,
RO_2 = 79,
WebBrowser = 80,
Test = 81,
ENC = 82,
PIA = 83,
Application = 254,
InvalidResult = 255
};
/// A less specific error cause.
enum class ErrorSummary : u32 {
Success = 0,
NothingHappened = 1,
WouldBlock = 2,
OutOfResource = 3, ///< There are no more kernel resources (memory, table slots) to
///< execute the operation.
NotFound = 4, ///< A file or resource was not found.
InvalidState = 5,
NotSupported = 6, ///< The operation is not supported or not implemented.
InvalidArgument = 7, ///< Returned when a passed argument is invalid in the current runtime
///< context. (Invalid handle, out-of-bounds pointer or size, etc.)
WrongArgument = 8, ///< Returned when a passed argument is in an incorrect format for use
///< with the function. (E.g. Invalid enum value)
Canceled = 9,
StatusChanged = 10,
Internal = 11,
InvalidResult = 63
};
/// The severity of the error.
enum class ErrorLevel : u32 {
Success = 0,
Info = 1,
Status = 25,
Temporary = 26,
Permanent = 27,
Usage = 28,
Reinitialize = 29,
Reset = 30,
Fatal = 31
};
/// Encapsulates a CTR-OS error code, allowing it to be separated into its constituent fields.
union ResultCode {
u32 raw;
BitField<0, 10, ErrorDescription> description;
BitField<10, 8, ErrorModule> module;
BitField<21, 6, ErrorSummary> summary;
BitField<27, 5, ErrorLevel> level;
// The last bit of `level` is checked by apps and the kernel to determine if a result code is an error
BitField<31, 1, u32> is_error;
explicit ResultCode(u32 raw) : raw(raw) {}
ResultCode(ErrorDescription description_, ErrorModule module_,
ErrorSummary summary_, ErrorLevel level_) : raw(0) {
description = description_;
module = module_;
summary = summary_;
level = level_;
}
ResultCode& operator=(const ResultCode& o) { raw = o.raw; return *this; }
bool IsSuccess() const {
return is_error == 0;
}
bool IsError() const {
return is_error == 1;
}
};
inline bool operator==(const ResultCode a, const ResultCode b) {
return a.raw == b.raw;
}
inline bool operator!=(const ResultCode a, const ResultCode b) {
return a.raw != b.raw;
}
// Convenience functions for creating some common kinds of errors:
/// The default success `ResultCode`.
const ResultCode RESULT_SUCCESS(0);
/// Might be returned instead of a dummy success for unimplemented APIs.
inline ResultCode UnimplementedFunction(ErrorModule module) {
return ResultCode(ErrorDescription::NotImplemented, module,
ErrorSummary::NotSupported, ErrorLevel::Permanent);
}
/// Returned when a function is passed an invalid handle.
inline ResultCode InvalidHandle(ErrorModule module) {
return ResultCode(ErrorDescription::InvalidHandle, module,
ErrorSummary::InvalidArgument, ErrorLevel::Permanent);
}
/**
* This is an optional value type. It holds a `ResultCode` and, if that code is a success code,
* also holds a result of type `T`. If the code is an error code then trying to access the inner
* value fails, thus ensuring that the ResultCode of functions is always checked properly before
* their return value is used. It is similar in concept to the `std::optional` type
* (http://en.cppreference.com/w/cpp/experimental/optional) originally proposed for inclusion in
* C++14, or the `Result` type in Rust (http://doc.rust-lang.org/std/result/index.html).
*
* An example of how it could be used:
* \code
* ResultVal<int> Frobnicate(float strength) {
* if (strength < 0.f || strength > 1.0f) {
* // Can't frobnicate too weakly or too strongly
* return ResultCode(ErrorDescription::OutOfRange, ErrorModule::Common,
* ErrorSummary::InvalidArgument, ErrorLevel::Permanent);
* } else {
* // Frobnicated! Give caller a cookie
* return MakeResult<int>(42);
* }
* }
* \endcode
*
* \code
* ResultVal<int> frob_result = Frobnicate(0.75f);
* if (frob_result) {
* // Frobbed ok
* printf("My cookie is %d\n", *frob_result);
* } else {
* printf("Guess I overdid it. :( Error code: %ux\n", frob_result.code().hex);
* }
* \endcode
*/
template <typename T>
class ResultVal {
public:
/// Constructs an empty `ResultVal` with the given error code. The code must not be a success code.
ResultVal(ResultCode error_code = ResultCode(-1))
: result_code(error_code)
{
assert(error_code.IsError());
UpdateDebugPtr();
}
/**
* Similar to the non-member function `MakeResult`, with the exception that you can manually
* specify the success code. `success_code` must not be an error code.
*/
template <typename... Args>
static ResultVal WithCode(ResultCode success_code, Args&&... args) {
ResultVal<T> result;
result.emplace(success_code, std::forward<Args>(args)...);
return result;
}
ResultVal(const ResultVal& o)
: result_code(o.result_code)
{
if (!o.empty()) {
new (&storage) T(*o.GetPointer());
}
UpdateDebugPtr();
}
ResultVal(ResultVal&& o)
: result_code(o.result_code)
{
if (!o.empty()) {
new (&storage) T(std::move(*o.GetPointer()));
}
UpdateDebugPtr();
}
~ResultVal() {
if (!empty()) {
GetPointer()->~T();
}
}
ResultVal& operator=(const ResultVal& o) {
if (*this) {
if (o) {
*GetPointer() = *o.GetPointer();
} else {
GetPointer()->~T();
}
} else {
if (o) {
new (&storage) T(*o.GetPointer());
}
}
result_code = o.result_code;
UpdateDebugPtr();
return *this;
}
/**
* Replaces the current result with a new constructed result value in-place. The code must not
* be an error code.
*/
template <typename... Args>
void emplace(ResultCode success_code, Args&&... args) {
assert(success_code.IsSuccess());
if (!empty()) {
GetPointer()->~T();
}
new (&storage) T(std::forward<Args>(args)...);
result_code = success_code;
UpdateDebugPtr();
}
/// Returns true if the `ResultVal` contains an error code and no value.
bool empty() const { return result_code.IsError(); }
/// Returns true if the `ResultVal` contains a return value.
bool Succeeded() const { return result_code.IsSuccess(); }
/// Returns true if the `ResultVal` contains an error code and no value.
bool Failed() const { return empty(); }
ResultCode Code() const { return result_code; }
const T& operator* () const { return *GetPointer(); }
T& operator* () { return *GetPointer(); }
const T* operator->() const { return GetPointer(); }
T* operator->() { return GetPointer(); }
/// Returns the value contained in this `ResultVal`, or the supplied default if it is missing.
template <typename U>
T ValueOr(U&& value) const {
return !empty() ? *GetPointer() : std::move(value);
}
/// Asserts that the result succeeded and returns a reference to it.
T& Unwrap() {
// TODO(yuriks): Should be a release assert
_assert_msg_(Common, Succeeded(), "Tried to Unwrap empty ResultVal");
return **this;
}
T&& MoveFrom() {
return std::move(Unwrap());
}
private:
typedef typename std::aligned_storage<sizeof(T), std::alignment_of<T>::value>::type StorageType;
StorageType storage;
ResultCode result_code;
#ifdef _DEBUG
// The purpose of this pointer is to aid inspecting the type with a debugger, eliminating the
// need to cast `storage` to a pointer or pay attention to `result_code`.
const T* debug_ptr;
#endif
void UpdateDebugPtr() {
#ifdef _DEBUG
debug_ptr = empty() ? nullptr : static_cast<const T*>(static_cast<const void*>(&storage));
#endif
}
const T* GetPointer() const {
assert(!empty());
return static_cast<const T*>(static_cast<const void*>(&storage));
}
T* GetPointer() {
assert(!empty());
return static_cast<T*>(static_cast<void*>(&storage));
}
};
/**
* This function is a helper used to construct `ResultVal`s. It receives the arguments to construct
* `T` with and creates a success `ResultVal` contained the constructed value.
*/
template <typename T, typename... Args>
ResultVal<T> MakeResult(Args&&... args) {
return ResultVal<T>::WithCode(RESULT_SUCCESS, std::forward<Args>(args)...);
}
/**
* Check for the success of `source` (which must evaluate to a ResultVal). If it succeeds, unwraps
* the contained value and assigns it to `target`, which can be either an l-value expression or a
* variable declaration. If it fails the return code is returned from the current function. Thus it
* can be used to cascade errors out, achieving something akin to exception handling.
*/
#define CASCADE_RESULT(target, source) \
auto CONCAT2(check_result_L, __LINE__) = source; \
if (CONCAT2(check_result_L, __LINE__).Failed()) \
return CONCAT2(check_result_L, __LINE__).Code(); \
target = std::move(*CONCAT2(check_result_L, __LINE__))
