result: Add [[nodiscard]] specifiers where applicable

The result code classes are used quite extensively throughout both the
kernel and service HLE code. We can mark these member functions as
[[nodiscard]] to prevent a few logic bugs from slipping through.
This commit is contained in:
Lioncash 2021-06-05 06:05:39 -04:00
parent fefc76e5da
commit 25b73e135f

View File

@ -124,21 +124,21 @@ union ResultCode {
constexpr ResultCode(ErrorModule module_, u32 description_)
: raw(module.FormatValue(module_) | description.FormatValue(description_)) {}
constexpr bool IsSuccess() const {
[[nodiscard]] constexpr bool IsSuccess() const {
return raw == 0;
}
constexpr bool IsError() const {
return raw != 0;
[[nodiscard]] constexpr bool IsError() const {
return !IsSuccess();
}
};
constexpr bool operator==(const ResultCode& a, const ResultCode& b) {
[[nodiscard]] constexpr bool operator==(const ResultCode& a, const ResultCode& b) {
return a.raw == b.raw;
}
constexpr bool operator!=(const ResultCode& a, const ResultCode& b) {
return a.raw != b.raw;
[[nodiscard]] constexpr bool operator!=(const ResultCode& a, const ResultCode& b) {
return !operator==(a, b);
}
// Convenience functions for creating some common kinds of errors:
@ -200,7 +200,7 @@ public:
* specify the success code. `success_code` must not be an error code.
*/
template <typename... Args>
static ResultVal WithCode(ResultCode success_code, Args&&... args) {
[[nodiscard]] static ResultVal WithCode(ResultCode success_code, Args&&... args) {
ResultVal<T> result;
result.emplace(success_code, std::forward<Args>(args)...);
return result;
@ -259,49 +259,49 @@ public:
}
/// Returns true if the `ResultVal` contains an error code and no value.
bool empty() const {
[[nodiscard]] bool empty() const {
return result_code.IsError();
}
/// Returns true if the `ResultVal` contains a return value.
bool Succeeded() const {
[[nodiscard]] bool Succeeded() const {
return result_code.IsSuccess();
}
/// Returns true if the `ResultVal` contains an error code and no value.
bool Failed() const {
[[nodiscard]] bool Failed() const {
return empty();
}
ResultCode Code() const {
[[nodiscard]] ResultCode Code() const {
return result_code;
}
const T& operator*() const {
[[nodiscard]] const T& operator*() const {
return object;
}
T& operator*() {
[[nodiscard]] T& operator*() {
return object;
}
const T* operator->() const {
[[nodiscard]] const T* operator->() const {
return &object;
}
T* operator->() {
[[nodiscard]] T* operator->() {
return &object;
}
/// Returns the value contained in this `ResultVal`, or the supplied default if it is missing.
template <typename U>
T ValueOr(U&& value) const {
[[nodiscard]] T ValueOr(U&& value) const {
return !empty() ? object : std::move(value);
}
/// Asserts that the result succeeded and returns a reference to it.
T& Unwrap() & {
[[nodiscard]] T& Unwrap() & {
ASSERT_MSG(Succeeded(), "Tried to Unwrap empty ResultVal");
return **this;
}
T&& Unwrap() && {
[[nodiscard]] T&& Unwrap() && {
ASSERT_MSG(Succeeded(), "Tried to Unwrap empty ResultVal");
return std::move(**this);
}
@ -320,7 +320,7 @@ private:
* `T` with and creates a success `ResultVal` contained the constructed value.
*/
template <typename T, typename... Args>
ResultVal<T> MakeResult(Args&&... args) {
[[nodiscard]] ResultVal<T> MakeResult(Args&&... args) {
return ResultVal<T>::WithCode(ResultSuccess, std::forward<Args>(args)...);
}
@ -329,7 +329,7 @@ ResultVal<T> MakeResult(Args&&... args) {
* copy or move constructing.
*/
template <typename Arg>
ResultVal<std::remove_reference_t<Arg>> MakeResult(Arg&& arg) {
[[nodiscard]] ResultVal<std::remove_reference_t<Arg>> MakeResult(Arg&& arg) {
return ResultVal<std::remove_reference_t<Arg>>::WithCode(ResultSuccess, std::forward<Arg>(arg));
}