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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
#ifndef DOM_QUOTA_QMRESULTINLINES_H_
#define DOM_QUOTA_QMRESULTINLINES_H_
#include "nsError.h"
#include "mozilla/Result.h"
#include "mozilla/ResultExtensions.h"
#include "mozilla/dom/QMResult.h"
#include "mozilla/dom/quota/Config.h"
#include "mozilla/dom/quota/RemoveParen.h"
#ifdef QM_ERROR_STACKS_ENABLED
# include "mozilla/ResultVariant.h"
#endif
namespace mozilla {
// Allow bool errors to automatically convert to bool values, so MOZ_TRY/QM_TRY
// can be used in bool returning methods with Result<T, bool> results.
template <>
class [[nodiscard]] GenericErrorResult<bool> {
bool mErrorValue;
template <typename V, typename E2>
friend class Result;
public:
explicit GenericErrorResult(bool aErrorValue) : mErrorValue(aErrorValue) {
MOZ_ASSERT(!aErrorValue);
}
GenericErrorResult(bool aErrorValue, const ErrorPropagationTag&)
: GenericErrorResult(aErrorValue) {}
MOZ_IMPLICIT operator bool() const { return mErrorValue; }
};
// Allow MOZ_TRY/QM_TRY to handle `bool` values.
template <typename E = nsresult>
inline Result<Ok, E> ToResult(bool aValue) {
if (aValue) {
return Ok();
}
return Err(ResultTypeTraits<E>::From(NS_ERROR_FAILURE));
}
constexpr nsresult ToNSResult(nsresult aError) { return aError; }
#ifdef QM_ERROR_STACKS_ENABLED
inline nsresult ToNSResult(const QMResult& aError) { return aError.NSResult(); }
// Allow QMResult errors to use existing stack id and to increase the frame id
// during error propagation.
template <>
class [[nodiscard]] GenericErrorResult<QMResult> {
QMResult mErrorValue;
template <typename V, typename E2>
friend class Result;
public:
explicit GenericErrorResult(const QMResult& aErrorValue)
: mErrorValue(aErrorValue) {
MOZ_ASSERT(NS_FAILED(aErrorValue.NSResult()));
}
explicit GenericErrorResult(QMResult&& aErrorValue)
: mErrorValue(std::move(aErrorValue)) {
MOZ_ASSERT(NS_FAILED(aErrorValue.NSResult()));
}
explicit GenericErrorResult(const QMResult& aErrorValue,
const ErrorPropagationTag&)
: GenericErrorResult(aErrorValue.Propagate()) {}
explicit GenericErrorResult(QMResult&& aErrorValue,
const ErrorPropagationTag&)
: GenericErrorResult(aErrorValue.Propagate()) {}
operator QMResult() const { return mErrorValue; }
operator nsresult() const { return mErrorValue.NSResult(); }
};
template <>
struct ResultTypeTraits<QMResult> {
static QMResult From(nsresult aValue) { return ToQMResult(aValue); }
static QMResult From(const QMResult& aValue) { return aValue; }
static QMResult From(QMResult&& aValue) { return std::move(aValue); }
};
template <typename E>
inline Result<Ok, E> ToResult(const QMResult& aValue) {
if (NS_FAILED(aValue.NSResult())) {
return Err(ResultTypeTraits<E>::From(aValue));
}
return Ok();
}
template <typename E>
inline Result<Ok, E> ToResult(QMResult&& aValue) {
if (NS_FAILED(aValue.NSResult())) {
return Err(ResultTypeTraits<E>::From(aValue));
}
return Ok();
}
#endif
template <typename E = nsresult, typename V, typename E2>
inline Result<V, E> ToResultTransform(Result<V, E2>&& aValue) {
return std::forward<Result<V, E2>>(aValue).mapErr(
[](auto&& err) { return ResultTypeTraits<E>::From(err); });
}
// TODO: Maybe move this to mfbt/ResultExtensions.h
template <typename R, typename Func, typename... Args>
Result<R, nsresult> ToResultGet(const Func& aFunc, Args&&... aArgs) {
nsresult rv;
R res = aFunc(std::forward<Args>(aArgs)..., &rv);
if (NS_FAILED(rv)) {
return Err(rv);
}
return res;
}
} // namespace mozilla
// TODO: Maybe move this to mfbt/ResultExtensions.h
#define MOZ_TO_RESULT(expr) ToResult(expr)
#define QM_TO_RESULT(expr) ToResult<QMResult>(expr)
#define QM_TO_RESULT_TRANSFORM(value) ToResultTransform<QMResult>(value)
#define MOZ_TO_RESULT_GET_TYPED(resultType, ...) \
::mozilla::ToResultGet<MOZ_REMOVE_PAREN(resultType)>(__VA_ARGS__)
#define MOZ_TO_RESULT_INVOKE_TYPED(resultType, ...) \
::mozilla::ToResultInvoke<MOZ_REMOVE_PAREN(resultType)>(__VA_ARGS__)
#define QM_TO_RESULT_INVOKE_MEMBER(obj, methodname, ...) \
::mozilla::ToResultInvokeMember<QMResult>( \
(obj), &::mozilla::detail::DerefedType<decltype(obj)>::methodname, \
##__VA_ARGS__)
#define QM_TO_RESULT_INVOKE_MEMBER_TYPED(resultType, obj, methodname, ...) \
(::mozilla::ToResultInvoke<resultType, QMResult>( \
::std::mem_fn( \
&::mozilla::detail::DerefedType<decltype(obj)>::methodname), \
(obj), ##__VA_ARGS__))
#endif