Atmosphere/libraries/libstratosphere/include/stratosphere/err/err_error_context.hpp

/*
 * Copyright (c) 2018-2020 Atmosphère-NX
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
#pragma once
#include <vapours.hpp>
#include <stratosphere/sf/sf_buffer_tags.hpp>

namespace ams::err {

    enum class ErrorContextType : u8 {
        None              = 0,
        Http              = 1,
        FileSystem        = 2,
        WebMediaPlayer    = 3,
        LocalContentShare = 4,
    };

    struct PaddingErrorContext {
        u8 padding[0x200 - 8];
    };

    struct ErrorContext : public sf::LargeData, public sf::PrefersMapAliasTransferMode {
        ErrorContextType type;
        u8 reserved[7];

        union {
            PaddingErrorContext padding;
        };
    };
    static_assert(sizeof(ErrorContext) == 0x200);
    static_assert(util::is_pod<ErrorContext>::value);

    struct ContextDescriptor {
        int value;

        constexpr ALWAYS_INLINE bool operator==(const ContextDescriptor &rhs) const { return this->value == rhs.value; }
        constexpr ALWAYS_INLINE bool operator!=(const ContextDescriptor &rhs) const { return this->value != rhs.value; }
        constexpr ALWAYS_INLINE bool operator< (const ContextDescriptor &rhs) const { return this->value <  rhs.value; }
        constexpr ALWAYS_INLINE bool operator<=(const ContextDescriptor &rhs) const { return this->value <= rhs.value; }
        constexpr ALWAYS_INLINE bool operator> (const ContextDescriptor &rhs) const { return this->value >  rhs.value; }
        constexpr ALWAYS_INLINE bool operator>=(const ContextDescriptor &rhs) const { return this->value >= rhs.value; }
    };

    constexpr inline const ContextDescriptor InvalidContextDescriptor{ -1 };

    namespace impl {

        constexpr inline const ContextDescriptor ContextDescriptorMin{ 0x001 };
        constexpr inline const ContextDescriptor ContextDescriptorMax{ 0x1FF };

    }

    constexpr Result MakeResultWithContextDescriptor(Result result, ContextDescriptor descriptor) {
        /* Check pre-conditions. */
        AMS_ASSERT(R_FAILED(result));
        AMS_ASSERT(descriptor != InvalidContextDescriptor);
        AMS_ASSERT(impl::ContextDescriptorMin <= descriptor && descriptor <= impl::ContextDescriptorMax);

        return result::impl::ResultInternalAccessor::MergeReserved(result, descriptor.value | 0x200);
    }

    constexpr ContextDescriptor GetContextDescriptorFromResult(Result result) {
        /* Check pre-conditions. */
        AMS_ASSERT(R_FAILED(result));

        /* Get reserved bits. */
        const auto reserved = result::impl::ResultInternalAccessor::GetReserved(result);
        if ((reserved & 0x200) != 0x200) {
            return InvalidContextDescriptor;
        }

        /* Check the descriptor value. */
        const ContextDescriptor descriptor{static_cast<decltype(ContextDescriptor{}.value)>(reserved & ~0x200)};
        if (!(impl::ContextDescriptorMin <= descriptor && descriptor <= impl::ContextDescriptorMax)) {
            return InvalidContextDescriptor;
        }

        return descriptor;
    }

}