//===----------------------------------------------------------------------===//

//

// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.

// See https://llvm.org/LICENSE.txt for license information.

// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

//

//

// This file implements the default terminate_handler, unexpected_handler and

// new_handler.

//===----------------------------------------------------------------------===//

#include <exception>

#include <memory>

#include <stdlib.h>

#include "abort_message.h"

#include "cxxabi.h"

#include "cxa_handlers.h"

#include "cxa_exception.h"

#include "private_typeinfo.h"

#include "include/atomic_support.h" // from libc++

#if !defined(LIBCXXABI_SILENT_TERMINATE)

static constinit const char* cause = "uncaught";

#ifndef _LIBCXXABI_NO_EXCEPTIONS

// Demangle the given string, or return the string as-is in case of an error.

static std::unique_ptr<char const, void (*)(char const*)> demangle(char const* str)

{

#if !defined(LIBCXXABI_NON_DEMANGLING_TERMINATE)

    if (const char* result = __cxxabiv1::__cxa_demangle(str, nullptr, nullptr, nullptr))

        return {result, [](char const* p) { std::free(const_cast<char*>(p)); }};

#endif

    return {str, [](char const*) { /* nothing to free */ }};

}

__attribute__((noreturn))

static void demangling_terminate_handler()

{

    using namespace __cxxabiv1;

    __cxa_eh_globals* globals = __cxa_get_globals_fast();

    // If there is no uncaught exception, just note that we're terminating

    if (!globals)

        abort_message("terminating");

    __cxa_exception* exception_header = globals->caughtExceptions;

    if (!exception_header)

        abort_message("terminating");

    _Unwind_Exception* unwind_exception =

        reinterpret_cast<_Unwind_Exception*>(exception_header + 1) - 1;

    // If we're terminating due to a foreign exception

    if (!__isOurExceptionClass(unwind_exception))

        abort_message("terminating due to %s foreign exception", cause);

    void* thrown_object =

        __getExceptionClass(unwind_exception) == kOurDependentExceptionClass ?

            ((__cxa_dependent_exception*)exception_header)->primaryException :

            exception_header + 1;

    const __shim_type_info* thrown_type =

        static_cast<const __shim_type_info*>(exception_header->exceptionType);

    auto name = demangle(thrown_type->name());

    // If the uncaught exception can be caught with std::exception&

    const __shim_type_info* catch_type =

        static_cast<const __shim_type_info*>(&typeid(std::exception));

    if (catch_type->can_catch(thrown_type, thrown_object))

    {

        // Include the what() message from the exception

        const std::exception* e = static_cast<const std::exception*>(thrown_object);

        abort_message("terminating due to %s exception of type %s: %s", cause, name.get(), e->what());

    }

    else

    {

        // Else just note that we're terminating due to an exception

        abort_message("terminating due to %s exception of type %s", cause, name.get());

    }

}

#else // !_LIBCXXABI_NO_EXCEPTIONS

__attribute__((noreturn))

static void demangling_terminate_handler()

{

    abort_message("terminating");

}

#endif // !_LIBCXXABI_NO_EXCEPTIONS

__attribute__((noreturn))

static void demangling_unexpected_handler()

{

    cause = "unexpected";

    std::terminate();

}

static constexpr std::terminate_handler default_terminate_handler = demangling_terminate_handler;

static constexpr std::terminate_handler default_unexpected_handler = demangling_unexpected_handler;

#else // !LIBCXXABI_SILENT_TERMINATE

static constexpr std::terminate_handler default_terminate_handler = ::abort;

static constexpr std::terminate_handler default_unexpected_handler = std::terminate;

#endif // !LIBCXXABI_SILENT_TERMINATE

//

// Global variables that hold the pointers to the current handler

//

_LIBCXXABI_DATA_VIS

constinit std::terminate_handler __cxa_terminate_handler = default_terminate_handler;

_LIBCXXABI_DATA_VIS

constinit std::unexpected_handler __cxa_unexpected_handler = default_unexpected_handler;

_LIBCXXABI_DATA_VIS

constinit std::new_handler __cxa_new_handler = nullptr;

namespace std

{

unexpected_handler

set_unexpected(unexpected_handler func) noexcept

{

    if (func == 0)

        func = default_unexpected_handler;

    return __libcpp_atomic_exchange(&__cxa_unexpected_handler, func,

                                    _AO_Acq_Rel);

}

terminate_handler

set_terminate(terminate_handler func) noexcept

{

    if (func == 0)

        func = default_terminate_handler;

    return __libcpp_atomic_exchange(&__cxa_terminate_handler, func,

                                    _AO_Acq_Rel);

}

new_handler

set_new_handler(new_handler handler) noexcept

{

    return __libcpp_atomic_exchange(&__cxa_new_handler, handler, _AO_Acq_Rel);

}

}