libcxx/src/support/runtime/exception_pointer_cxxabi.ipp

// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//

#ifndef HAVE_DEPENDENT_EH_ABI
#  error this header may only be used with libc++abi or libcxxrt
#endif

namespace std {

exception_ptr::~exception_ptr() noexcept { __cxa_decrement_exception_refcount(__ptr_); }

exception_ptr::exception_ptr(const exception_ptr& other) noexcept : __ptr_(other.__ptr_) {
  __cxa_increment_exception_refcount(__ptr_);
}

exception_ptr& exception_ptr::operator=(const exception_ptr& other) noexcept {
  if (__ptr_ != other.__ptr_) {
    __cxa_increment_exception_refcount(other.__ptr_);
    __cxa_decrement_exception_refcount(__ptr_);
    __ptr_ = other.__ptr_;
  }
  return *this;
}

exception_ptr exception_ptr::__from_native_exception_pointer(void* __e) noexcept {
  exception_ptr ptr;
  ptr.__ptr_ = __e;
  __cxa_increment_exception_refcount(ptr.__ptr_);

  return ptr;
}

nested_exception::nested_exception() noexcept : __ptr_(current_exception()) {}

nested_exception::~nested_exception() noexcept {}

_LIBCPP_NORETURN void nested_exception::rethrow_nested() const {
  if (__ptr_ == nullptr)
    terminate();
  rethrow_exception(__ptr_);
}

exception_ptr current_exception() noexcept {
  // be nicer if there was a constructor that took a ptr, then
  // this whole function would be just:
  //    return exception_ptr(__cxa_current_primary_exception());
  exception_ptr ptr;
  ptr.__ptr_ = __cxa_current_primary_exception();
  return ptr;
}

_LIBCPP_NORETURN void rethrow_exception(exception_ptr p) {
  __cxa_rethrow_primary_exception(p.__ptr_);
  // if p.__ptr_ is NULL, above returns so we terminate
  terminate();
}

} // namespace std