1// -*- C++ -*- Manage the thread-local exception globals. 2// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006 3// Free Software Foundation, Inc. 4// 5// This file is part of GCC. 6// 7// GCC is free software; you can redistribute it and/or modify 8// it under the terms of the GNU General Public License as published by 9// the Free Software Foundation; either version 2, or (at your option) 10// any later version. 11// 12// GCC is distributed in the hope that it will be useful, 13// but WITHOUT ANY WARRANTY; without even the implied warranty of 14// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15// GNU General Public License for more details. 16// 17// You should have received a copy of the GNU General Public License 18// along with GCC; see the file COPYING. If not, write to 19// the Free Software Foundation, 51 Franklin Street, Fifth Floor, 20// Boston, MA 02110-1301, USA. 21 22// As a special exception, you may use this file as part of a free software 23// library without restriction. Specifically, if other files instantiate 24// templates or use macros or inline functions from this file, or you compile 25// this file and link it with other files to produce an executable, this 26// file does not by itself cause the resulting executable to be covered by 27// the GNU General Public License. This exception does not however 28// invalidate any other reasons why the executable file might be covered by 29// the GNU General Public License. 30 31#include <bits/c++config.h> 32#include <exception> 33#include <cstdlib> 34#include "cxxabi.h" 35#include "unwind-cxx.h" 36#include "bits/gthr.h" 37 38#if _GLIBCXX_HOSTED 39using std::free; 40using std::malloc; 41#else 42// In a freestanding environment, these functions may not be 43// available -- but for now, we assume that they are. 44extern "C" void *malloc (std::size_t); 45extern "C" void free(void *); 46#endif 47 48using namespace __cxxabiv1; 49 50#if _GLIBCXX_HAVE_TLS 51 52namespace 53{ 54 abi::__cxa_eh_globals* 55 get_global() throw() 56 { 57 static __thread abi::__cxa_eh_globals global; 58 return &global; 59 } 60} // anonymous namespace 61 62extern "C" __cxa_eh_globals* 63__cxxabiv1::__cxa_get_globals_fast() throw() 64{ return get_global(); } 65 66extern "C" __cxa_eh_globals* 67__cxxabiv1::__cxa_get_globals() throw() 68{ return get_global(); } 69 70 71#else 72 73// Single-threaded fallback buffer. 74static __cxa_eh_globals eh_globals; 75 76#if __GTHREADS 77 78static void 79eh_globals_dtor(void* ptr) 80{ 81 if (ptr) 82 { 83 __cxa_eh_globals* g = reinterpret_cast<__cxa_eh_globals*>(ptr); 84 __cxa_exception* exn = g->caughtExceptions; 85 __cxa_exception* next; 86 while (exn) 87 { 88 next = exn->nextException; 89 _Unwind_DeleteException(&exn->unwindHeader); 90 exn = next; 91 } 92 free(ptr); 93 } 94} 95 96struct __eh_globals_init 97{ 98 __gthread_key_t _M_key; 99 bool _M_init; 100 101 __eh_globals_init() : _M_init(false) 102 { 103 if (__gthread_active_p()) 104 _M_init = __gthread_key_create(&_M_key, eh_globals_dtor) == 0; 105 } 106 107 ~__eh_globals_init() 108 { 109 if (_M_init) 110 __gthread_key_delete(_M_key); 111 _M_init = false; 112 } 113}; 114 115static __eh_globals_init init; 116 117extern "C" __cxa_eh_globals* 118__cxxabiv1::__cxa_get_globals_fast() throw() 119{ 120 __cxa_eh_globals* g; 121 if (init._M_init) 122 g = static_cast<__cxa_eh_globals*>(__gthread_getspecific(init._M_key)); 123 else 124 g = &eh_globals; 125 return g; 126} 127 128extern "C" __cxa_eh_globals* 129__cxxabiv1::__cxa_get_globals() throw() 130{ 131 __cxa_eh_globals* g; 132 if (init._M_init) 133 { 134 g = static_cast<__cxa_eh_globals*>(__gthread_getspecific(init._M_key)); 135 if (!g) 136 { 137 void* v = malloc(sizeof(__cxa_eh_globals)); 138 if (v == 0 || __gthread_setspecific(init._M_key, v) != 0) 139 std::terminate(); 140 g = static_cast<__cxa_eh_globals*>(v); 141 g->caughtExceptions = 0; 142 g->uncaughtExceptions = 0; 143 } 144 } 145 else 146 g = &eh_globals; 147 return g; 148} 149 150#else 151 152extern "C" __cxa_eh_globals* 153__cxxabiv1::__cxa_get_globals_fast() throw() 154{ return &eh_globals; } 155 156extern "C" __cxa_eh_globals* 157__cxxabiv1::__cxa_get_globals() throw() 158{ return &eh_globals; } 159 160#endif 161 162#endif 163