libstdc++-v3/libsupc++/eh_throw.cc

   1 // -*- C++ -*- Exception handling routines for throwing.
   2 // Copyright (C) 2001, 2003 Free Software Foundation, Inc.
   3 //
   4 // This file is part of GCC.
   5 //
   6 // GCC is free software; you can redistribute it and/or modify
   7 // it under the terms of the GNU General Public License as published by
   8 // the Free Software Foundation; either version 2, or (at your option)
   9 // any later version.
  10 //
  11 // GCC is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15 //
  16 // You should have received a copy of the GNU General Public License
  17 // along with GCC; see the file COPYING.  If not, write to
  18 // the Free Software Foundation, 59 Temple Place - Suite 330,
  19 // Boston, MA 02111-1307, USA.
  20
  21 // As a special exception, you may use this file as part of a free software
  22 // library without restriction.  Specifically, if other files instantiate
  23 // templates or use macros or inline functions from this file, or you compile
  24 // this file and link it with other files to produce an executable, this
  25 // file does not by itself cause the resulting executable to be covered by
  26 // the GNU General Public License.  This exception does not however
  27 // invalidate any other reasons why the executable file might be covered by
  28 // the GNU General Public License.
  29
  30
  31 #include <bits/c++config.h>
  32 #include "unwind-cxx.h"
  33
  34
  35 using namespace __cxxabiv1;
  36
  37
  38 static void
  39 __gxx_exception_cleanup (_Unwind_Reason_Code code, _Unwind_Exception *exc)
  40 {
  41   __cxa_exception *header = __get_exception_header_from_ue (exc);
  42
  43   // If we haven't been caught by a foreign handler, then this is
  44   // some sort of unwind error.  In that case just die immediately.
  45   // _Unwind_DeleteException in the HP-UX IA64 libunwind library
  46   //  returns _URC_NO_REASON and not _URC_FOREIGN_EXCEPTION_CAUGHT
  47   // like the GCC _Unwind_DeleteException function does.
  48   if (code != _URC_FOREIGN_EXCEPTION_CAUGHT && code != _URC_NO_REASON)
  49     __terminate (header->terminateHandler);
  50
  51   if (header->exceptionDestructor)
  52     header->exceptionDestructor (header + 1);
  53
  54   __cxa_free_exception (header + 1);
  55 }
  56
  57
  58 extern "C" void
  59 __cxa_throw (void *obj, std::type_info *tinfo, void (*dest) (void *))
  60 {
  61   __cxa_exception *header = __get_exception_header_from_obj (obj);
  62   header->exceptionType = tinfo;
  63   header->exceptionDestructor = dest;
  64   header->unexpectedHandler = __unexpected_handler;
  65   header->terminateHandler = __terminate_handler;
  66   header->unwindHeader.exception_class = __gxx_exception_class;
  67   header->unwindHeader.exception_cleanup = __gxx_exception_cleanup;
  68
  69   __cxa_eh_globals *globals = __cxa_get_globals ();
  70   globals->uncaughtExceptions += 1;
  71
  72 #ifdef _GLIBCXX_SJLJ_EXCEPTIONS
  73   _Unwind_SjLj_RaiseException (&header->unwindHeader);
  74 #else
  75   _Unwind_RaiseException (&header->unwindHeader);
  76 #endif
  77
  78   // Some sort of unwinding error.  Note that terminate is a handler.
  79   __cxa_begin_catch (&header->unwindHeader);
  80   std::terminate ();
  81 }
  82
  83 extern "C" void
  84 __cxa_rethrow ()
  85 {
  86   __cxa_eh_globals *globals = __cxa_get_globals ();
  87   __cxa_exception *header = globals->caughtExceptions;
  88
  89   // Watch for luser rethrowing with no active exception.
  90   if (header)
  91     {
  92       // Tell __cxa_end_catch this is a rethrow.
  93       if (header->unwindHeader.exception_class != __gxx_exception_class)
  94         globals->caughtExceptions = 0;
  95       else
  96         header->handlerCount = -header->handlerCount;
  97
  98 #ifdef _GLIBCXX_SJLJ_EXCEPTIONS
  99       _Unwind_SjLj_Resume_or_Rethrow (&header->unwindHeader);
 100 #else
 101 #ifdef _LIBUNWIND_STD_ABI
 102       _Unwind_RaiseException (&header->unwindHeader);
 103 #else
 104       _Unwind_Resume_or_Rethrow (&header->unwindHeader);
 105 #endif
 106 #endif
 107
 108       // Some sort of unwinding error.  Note that terminate is a handler.
 109       __cxa_begin_catch (&header->unwindHeader);
 110     }
 111   std::terminate ();
 112 }