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// -*- C++ -*- Exception handling routines for catching.
// Copyright (C) 2001, 2003, 2004 Free Software Foundation, Inc.
//
// This file is part of GCC.
//
// GCC is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2, or (at your option)
// any later version.
//
// GCC is distributed in the hope that 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 GCC; see the file COPYING. If not, write to
// the Free Software Foundation, 59 Temple Place - Suite 330,
// Boston, MA 02111-1307, USA.
// As a special exception, you may use this file as part of a free software
// library without restriction. Specifically, if other files instantiate
// templates or use macros or inline functions from this file, or you compile
// this file and link it with other files to produce an executable, this
// file does not by itself cause the resulting executable to be covered by
// the GNU General Public License. This exception does not however
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.
#include <cstdlib>
#include "unwind-cxx.h"
using namespace __cxxabiv1;
extern "C" void *
__cxa_begin_catch (void *exc_obj_in) throw()
{
_Unwind_Exception *exceptionObject
= reinterpret_cast <_Unwind_Exception *>(exc_obj_in);
__cxa_eh_globals *globals = __cxa_get_globals ();
__cxa_exception *prev = globals->caughtExceptions;
__cxa_exception *header = __get_exception_header_from_ue (exceptionObject);
// Foreign exceptions can't be stacked here. If the exception stack is
// empty, then fine. Otherwise we really have no choice but to terminate.
// Note that this use of "header" is a lie. It's fine so long as we only
// examine header->unwindHeader though.
if (header->unwindHeader.exception_class != __gxx_exception_class)
{
if (prev != 0)
std::terminate ();
// Remember for end_catch and rethrow.
globals->caughtExceptions = header;
// ??? No sensible value to return; we don't know what the
// object is, much less where it is in relation to the header.
return 0;
}
int count = header->handlerCount;
if (count < 0)
// This exception was rethrown from an immediately enclosing region.
count = -count + 1;
else
{
count += 1;
globals->uncaughtExceptions -= 1;
}
header->handlerCount = count;
if (header != prev)
{
header->nextException = prev;
globals->caughtExceptions = header;
}
return header->adjustedPtr;
}
extern "C" void
__cxa_end_catch ()
{
__cxa_eh_globals *globals = __cxa_get_globals_fast ();
__cxa_exception *header = globals->caughtExceptions;
// A rethrow of a foreign exception will be removed from the
// the exception stack immediately by __cxa_rethrow.
if (!header)
return;
// A foreign exception couldn't have been stacked (see above),
// so by definition processing must be complete.
if (header->unwindHeader.exception_class != __gxx_exception_class)
{
globals->caughtExceptions = 0;
_Unwind_DeleteException (&header->unwindHeader);
return;
}
int count = header->handlerCount;
if (count < 0)
{
// This exception was rethrown. Decrement the (inverted) catch
// count and remove it from the chain when it reaches zero.
if (++count == 0)
{
globals->uncaughtExceptions += 1;
globals->caughtExceptions = header->nextException;
}
}
else if (--count == 0)
{
// Handling for this exception is complete. Destroy the object.
globals->caughtExceptions = header->nextException;
_Unwind_DeleteException (&header->unwindHeader);
return;
}
else if (count < 0)
// A bug in the exception handling library or compiler.
std::terminate ();
header->handlerCount = count;
}
bool
std::uncaught_exception() throw()
{
__cxa_eh_globals *globals = __cxa_get_globals ();
return globals->uncaughtExceptions != 0;
}
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