1 // -*- C++ -*- Exception handling routines for catching.
2 // Copyright (C) 2001, 2003, 2004 Free Software Foundation, Inc.
4 // This file is part of GCC.
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)
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.
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.
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.
32 #include "unwind-cxx.h"
34 using namespace __cxxabiv1;
37 __cxxabiv1::__cxa_get_exception_ptr(void *exc_obj_in) throw()
39 _Unwind_Exception *exceptionObject
40 = reinterpret_cast <_Unwind_Exception *>(exc_obj_in);
41 __cxa_exception *header = __get_exception_header_from_ue (exceptionObject);
43 return header->adjustedPtr;
47 __cxxabiv1::__cxa_begin_catch (void *exc_obj_in) throw()
49 _Unwind_Exception *exceptionObject
50 = reinterpret_cast <_Unwind_Exception *>(exc_obj_in);
51 __cxa_eh_globals *globals = __cxa_get_globals ();
52 __cxa_exception *prev = globals->caughtExceptions;
53 __cxa_exception *header = __get_exception_header_from_ue (exceptionObject);
55 // Foreign exceptions can't be stacked here. If the exception stack is
56 // empty, then fine. Otherwise we really have no choice but to terminate.
57 // Note that this use of "header" is a lie. It's fine so long as we only
58 // examine header->unwindHeader though.
59 if (header->unwindHeader.exception_class != __gxx_exception_class)
64 // Remember for end_catch and rethrow.
65 globals->caughtExceptions = header;
67 // ??? No sensible value to return; we don't know what the
68 // object is, much less where it is in relation to the header.
72 int count = header->handlerCount;
73 // Count is less than zero if this exception was rethrown from an
74 // immediately enclosing region.
79 header->handlerCount = count;
80 globals->uncaughtExceptions -= 1;
84 header->nextException = prev;
85 globals->caughtExceptions = header;
88 return header->adjustedPtr;
93 __cxxabiv1::__cxa_end_catch ()
95 __cxa_eh_globals *globals = __cxa_get_globals_fast ();
96 __cxa_exception *header = globals->caughtExceptions;
98 // A rethrow of a foreign exception will be removed from the
99 // the exception stack immediately by __cxa_rethrow.
103 // A foreign exception couldn't have been stacked (see above),
104 // so by definition processing must be complete.
105 if (header->unwindHeader.exception_class != __gxx_exception_class)
107 globals->caughtExceptions = 0;
108 _Unwind_DeleteException (&header->unwindHeader);
112 int count = header->handlerCount;
115 // This exception was rethrown. Decrement the (inverted) catch
116 // count and remove it from the chain when it reaches zero.
118 globals->caughtExceptions = header->nextException;
120 else if (--count == 0)
122 // Handling for this exception is complete. Destroy the object.
123 globals->caughtExceptions = header->nextException;
124 _Unwind_DeleteException (&header->unwindHeader);
128 // A bug in the exception handling library or compiler.
131 header->handlerCount = count;
136 std::uncaught_exception() throw()
138 __cxa_eh_globals *globals = __cxa_get_globals ();
139 return globals->uncaughtExceptions != 0;