//*********************************************************
//
//    Copyright (c) Microsoft. All rights reserved.
//    This code is licensed under the MIT License.
//    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
//    ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
//    TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
//    PARTICULAR PURPOSE AND NONINFRINGEMENT.
//
//*********************************************************
//! @file
//! WIL Error Handling Helpers: supporting file enabling the originating of errors to produce better crash dumps

// Note: When origination is enabled by including this file, origination is done as part of the RETURN_* and THROW_* macros.
// Before originating a new error we will observe whether there is already an error payload associated with the current thread. If
// there is, and the HRESULTs match, then a new error will not be originated.  Otherwise we will overwrite it with a new
// origination.  The ABI boundary for WinRT APIs will check the per-thread error information.  The act of checking the error
// clears it, so there should be minimal risk of failing to originate distinct errors simply because the HRESULTs match.
//
// For THROW_ macros we will examine the thread-local error storage once per throw.  So typically once, with additional calls if
// the exception is caught and re-thrown.
//
// For RETURN_ macros we will have to examine the thread-local error storage once per frame as the call stack unwinds.  Because
// error conditions -should- be uncommon the performance impact of checking TLS should be minimal.  The more expensive part is
// originating the error because it must capture the entire stack and some additional data.

#ifndef __WIL_RESULT_ORIGINATE_INCLUDED
#define __WIL_RESULT_ORIGINATE_INCLUDED

#include "result.h"
#include <OleAuto.h> // RestrictedErrorInfo uses BSTRs :(
#include <winstring.h>
#include "resource.h"
#include "com.h"
#include <roerrorapi.h>

namespace wil
{
/// @cond
namespace details
{
    // Note: The name must begin with "Raise" so that the !analyze auto-bucketing will ignore this stack frame.  Otherwise this line of code gets all the blame.
    inline void __stdcall RaiseRoOriginateOnWilExceptions(wil::FailureInfo const& failure) WI_NOEXCEPT
    {
        if ((failure.type == FailureType::Return) || (failure.type == FailureType::Exception))
        {
            bool shouldOriginate = true;

            wil::com_ptr_nothrow<IRestrictedErrorInfo> restrictedErrorInformation;
            if (GetRestrictedErrorInfo(&restrictedErrorInformation) == S_OK)
            {
                // This thread already has an error origination payload.  Don't originate again if it has the same HRESULT that we
                // are observing right now.
                wil::unique_bstr descriptionUnused;
                HRESULT existingHr = failure.hr;
                wil::unique_bstr restrictedDescriptionUnused;
                wil::unique_bstr capabilitySidUnused;
                if (SUCCEEDED(restrictedErrorInformation->GetErrorDetails(
                        &descriptionUnused, &existingHr, &restrictedDescriptionUnused, &capabilitySidUnused)))
                {
                    shouldOriginate = (failure.hr != existingHr);
                }
            }

            if (shouldOriginate)
            {
#if WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP | WINAPI_PARTITION_SYSTEM)
                wil::unique_hmodule errorModule;
                if (GetModuleHandleExW(0, L"api-ms-win-core-winrt-error-l1-1-1.dll", &errorModule))
                {
                    auto pfn = reinterpret_cast<decltype(&::RoOriginateErrorW)>(GetProcAddress(errorModule.get(), "RoOriginateErrorW"));
                    if (pfn != nullptr)
                    {
                        pfn(failure.hr, 0, failure.pszMessage);
                    }
                }
#else  // DESKTOP | SYSTEM
                ::RoOriginateErrorW(failure.hr, 0, failure.pszMessage);
#endif // DESKTOP | SYSTEM
            }
            else if (restrictedErrorInformation)
            {
                // GetRestrictedErrorInfo returns ownership of the error information.  If we aren't originating, and an error was
                // already present, then we need to restore the error information for later observation.
                SetRestrictedErrorInfo(restrictedErrorInformation.get());
            }
        }
    }

    // This method will check for the presence of stowed exception data on the current thread.  If such data exists, and the
    // HRESULT matches the current failure, then we will call RoFailFastWithErrorContext.  RoFailFastWithErrorContext in this
    // situation will result in -VASTLY- improved crash bucketing.  It is hard to express just how much better.  In other cases we
    // just return and the calling method fails fast the same way it always has.
    inline void __stdcall FailfastWithContextCallback(wil::FailureInfo const& failure) WI_NOEXCEPT
    {
        wil::com_ptr_nothrow<IRestrictedErrorInfo> restrictedErrorInformation;
        if (GetRestrictedErrorInfo(&restrictedErrorInformation) == S_OK)
        {
            wil::unique_bstr descriptionUnused;
            HRESULT existingHr = failure.hr;
            wil::unique_bstr restrictedDescriptionUnused;
            wil::unique_bstr capabilitySidUnused;
            if (SUCCEEDED(restrictedErrorInformation->GetErrorDetails(
                    &descriptionUnused, &existingHr, &restrictedDescriptionUnused, &capabilitySidUnused)) &&
                (existingHr == failure.hr))
            {
                // GetRestrictedErrorInfo returns ownership of the error information.  We want it to be available for
                // RoFailFastWithErrorContext so we must restore it via SetRestrictedErrorInfo first.
                SetRestrictedErrorInfo(restrictedErrorInformation.get());
                RoFailFastWithErrorContext(existingHr);
            }
            else
            {
                // The error didn't match the current failure.  Put it back in thread-local storage even though we aren't failing
                // fast in this method, so it is available in the debugger just-in-case.
                SetRestrictedErrorInfo(restrictedErrorInformation.get());
            }
        }
    }
} // namespace details
/// @endcond
} // namespace wil

// Automatically call RoOriginateError upon error origination by including this file
WI_HEADER_INITITALIZATION_FUNCTION(ResultStowedExceptionInitialize, [] {
    ::wil::SetOriginateErrorCallback(::wil::details::RaiseRoOriginateOnWilExceptions);
    ::wil::SetFailfastWithContextCallback(::wil::details::FailfastWithContextCallback);
    return 1;
})

#endif // __WIL_RESULT_ORIGINATE_INCLUDED