llvm-project/libcxx/src/exception.cpp

308 lines
8.0 KiB
C++

//===------------------------ exception.cpp -------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include <stdlib.h>
#include <stdio.h>
#include "exception"
#include "new"
#ifndef __has_include
#define __has_include(inc) 0
#endif
#ifdef __APPLE__
#include <cxxabi.h>
using namespace __cxxabiv1;
#define HAVE_DEPENDENT_EH_ABI 1
#ifndef _LIBCPPABI_VERSION
using namespace __cxxabiapple;
// On Darwin, there are two STL shared libraries and a lower level ABI
// shared library. The globals holding the current terminate handler and
// current unexpected handler are in the ABI library.
#define __terminate_handler __cxxabiapple::__cxa_terminate_handler
#define __unexpected_handler __cxxabiapple::__cxa_unexpected_handler
#endif // _LIBCPPABI_VERSION
#elif defined(LIBCXXRT) || __has_include(<cxxabi.h>)
#include <cxxabi.h>
using namespace __cxxabiv1;
#if defined(LIBCXXRT) || defined(_LIBCPPABI_VERSION)
#define HAVE_DEPENDENT_EH_ABI 1
#endif
#elif !defined(__GLIBCXX__) // __has_include(<cxxabi.h>)
static std::terminate_handler __terminate_handler;
static std::unexpected_handler __unexpected_handler;
#endif // __has_include(<cxxabi.h>)
namespace std
{
#if !defined(LIBCXXRT) && !defined(_LIBCPPABI_VERSION) && !defined(__GLIBCXX__)
// libcxxrt provides implementations of these functions itself.
unexpected_handler
set_unexpected(unexpected_handler func) _NOEXCEPT
{
return __sync_lock_test_and_set(&__unexpected_handler, func);
}
unexpected_handler
get_unexpected() _NOEXCEPT
{
return __sync_fetch_and_add(&__unexpected_handler, (unexpected_handler)0);
}
_LIBCPP_NORETURN
void
unexpected()
{
(*get_unexpected())();
// unexpected handler should not return
terminate();
}
terminate_handler
set_terminate(terminate_handler func) _NOEXCEPT
{
return __sync_lock_test_and_set(&__terminate_handler, func);
}
terminate_handler
get_terminate() _NOEXCEPT
{
return __sync_fetch_and_add(&__terminate_handler, (terminate_handler)0);
}
#ifndef __EMSCRIPTEN__ // We provide this in JS
_LIBCPP_NORETURN
void
terminate() _NOEXCEPT
{
#ifndef _LIBCPP_NO_EXCEPTIONS
try
{
#endif // _LIBCPP_NO_EXCEPTIONS
(*get_terminate())();
// handler should not return
printf("terminate_handler unexpectedly returned\n");
::abort();
#ifndef _LIBCPP_NO_EXCEPTIONS
}
catch (...)
{
// handler should not throw exception
printf("terminate_handler unexpectedly threw an exception\n");
::abort();
}
#endif // _LIBCPP_NO_EXCEPTIONS
}
#endif // !__EMSCRIPTEN__
#endif // !defined(LIBCXXRT) && !defined(_LIBCPPABI_VERSION)
#if !defined(LIBCXXRT) && !defined(__GLIBCXX__) && !defined(__EMSCRIPTEN__)
bool uncaught_exception() _NOEXCEPT
{
#if defined(__APPLE__) || defined(_LIBCPPABI_VERSION)
// on Darwin, there is a helper function so __cxa_get_globals is private
return __cxa_uncaught_exception();
#else // __APPLE__
# if defined(_MSC_VER) && ! defined(__clang__)
_LIBCPP_WARNING("uncaught_exception not yet implemented")
# else
# warning uncaught_exception not yet implemented
# endif
printf("uncaught_exception not yet implemented\n");
::abort();
#endif // __APPLE__
}
#ifndef _LIBCPPABI_VERSION
exception::~exception() _NOEXCEPT
{
}
const char* exception::what() const _NOEXCEPT
{
return "std::exception";
}
#endif // _LIBCPPABI_VERSION
#endif //LIBCXXRT
#if !defined(_LIBCPPABI_VERSION) && !defined(__GLIBCXX__)
bad_exception::~bad_exception() _NOEXCEPT
{
}
const char* bad_exception::what() const _NOEXCEPT
{
return "std::bad_exception";
}
#endif
#if defined(__GLIBCXX__)
// libsupc++ does not implement the dependent EH ABI and the functionality
// it uses to implement std::exception_ptr (which it declares as an alias of
// std::__exception_ptr::exception_ptr) is not directly exported to clients. So
// we have little choice but to hijack std::__exception_ptr::exception_ptr's
// (which fortunately has the same layout as our std::exception_ptr) copy
// constructor, assignment operator and destructor (which are part of its
// stable ABI), and its rethrow_exception(std::__exception_ptr::exception_ptr)
// function.
namespace __exception_ptr
{
struct exception_ptr
{
void* __ptr_;
exception_ptr(const exception_ptr&) _NOEXCEPT;
exception_ptr& operator=(const exception_ptr&) _NOEXCEPT;
~exception_ptr() _NOEXCEPT;
};
}
_LIBCPP_NORETURN void rethrow_exception(__exception_ptr::exception_ptr);
#endif
exception_ptr::~exception_ptr() _NOEXCEPT
{
#if HAVE_DEPENDENT_EH_ABI
__cxa_decrement_exception_refcount(__ptr_);
#elif defined(__GLIBCXX__)
reinterpret_cast<__exception_ptr::exception_ptr*>(this)->~exception_ptr();
#else
# if defined(_MSC_VER) && ! defined(__clang__)
_LIBCPP_WARNING("exception_ptr not yet implemented")
# else
# warning exception_ptr not yet implemented
# endif
printf("exception_ptr not yet implemented\n");
::abort();
#endif
}
exception_ptr::exception_ptr(const exception_ptr& other) _NOEXCEPT
: __ptr_(other.__ptr_)
{
#if HAVE_DEPENDENT_EH_ABI
__cxa_increment_exception_refcount(__ptr_);
#elif defined(__GLIBCXX__)
new (reinterpret_cast<void*>(this)) __exception_ptr::exception_ptr(
reinterpret_cast<const __exception_ptr::exception_ptr&>(other));
#else
# if defined(_MSC_VER) && ! defined(__clang__)
_LIBCPP_WARNING("exception_ptr not yet implemented")
# else
# warning exception_ptr not yet implemented
# endif
printf("exception_ptr not yet implemented\n");
::abort();
#endif
}
exception_ptr& exception_ptr::operator=(const exception_ptr& other) _NOEXCEPT
{
#if HAVE_DEPENDENT_EH_ABI
if (__ptr_ != other.__ptr_)
{
__cxa_increment_exception_refcount(other.__ptr_);
__cxa_decrement_exception_refcount(__ptr_);
__ptr_ = other.__ptr_;
}
return *this;
#elif defined(__GLIBCXX__)
*reinterpret_cast<__exception_ptr::exception_ptr*>(this) =
reinterpret_cast<const __exception_ptr::exception_ptr&>(other);
return *this;
#else
# if defined(_MSC_VER) && ! defined(__clang__)
_LIBCPP_WARNING("exception_ptr not yet implemented")
# else
# warning exception_ptr not yet implemented
# endif
printf("exception_ptr not yet implemented\n");
::abort();
#endif
}
nested_exception::nested_exception() _NOEXCEPT
: __ptr_(current_exception())
{
}
#if !defined(__GLIBCXX__)
nested_exception::~nested_exception() _NOEXCEPT
{
}
#endif
_LIBCPP_NORETURN
void
nested_exception::rethrow_nested() const
{
if (__ptr_ == nullptr)
terminate();
rethrow_exception(__ptr_);
}
#if !defined(__GLIBCXX__)
exception_ptr current_exception() _NOEXCEPT
{
#if HAVE_DEPENDENT_EH_ABI
// 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;
#else
# if defined(_MSC_VER) && ! defined(__clang__)
_LIBCPP_WARNING( "exception_ptr not yet implemented" )
# else
# warning exception_ptr not yet implemented
# endif
printf("exception_ptr not yet implemented\n");
::abort();
#endif
}
#endif // !__GLIBCXX__
_LIBCPP_NORETURN
void rethrow_exception(exception_ptr p)
{
#if HAVE_DEPENDENT_EH_ABI
__cxa_rethrow_primary_exception(p.__ptr_);
// if p.__ptr_ is NULL, above returns so we terminate
terminate();
#elif defined(__GLIBCXX__)
rethrow_exception(reinterpret_cast<__exception_ptr::exception_ptr&>(p));
#else
# if defined(_MSC_VER) && ! defined(__clang__)
_LIBCPP_WARNING("exception_ptr not yet implemented")
# else
# warning exception_ptr not yet implemented
# endif
printf("exception_ptr not yet implemented\n");
::abort();
#endif
}
} // std