xref: /openbsd-src/gnu/gcc/libstdc++-v3/include/ext/throw_allocator.h (revision 12bb21d578ad369b898c185f93f157593a02e306)
1 // -*- C++ -*-
2 
3 // Copyright (C) 2005, 2006 Free Software Foundation, Inc.
4 //
5 // This file is part of the GNU ISO C++ Library.  This library is free
6 // software; you can redistribute it and/or modify it under the terms
7 // of the GNU General Public License as published by the Free Software
8 // Foundation; either version 2, or (at your option) any later
9 // version.
10 
11 // This library is distributed in the hope that it will be useful, but
12 // WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14 // General Public License for more details.
15 
16 // You should have received a copy of the GNU General Public License
17 // along with this library; see the file COPYING.  If not, write to
18 // the Free Software Foundation, 59 Temple Place - Suite 330, Boston,
19 // MA 02111-1307, USA.
20 
21 // As a special exception, you may use this file as part of a free
22 // software library without restriction.  Specifically, if other files
23 // instantiate templates or use macros or inline functions from this
24 // file, or you compile this file and link it with other files to
25 // produce an executable, this file does not by itself cause the
26 // resulting executable to be covered by the GNU General Public
27 // License.  This exception does not however invalidate any other
28 // reasons why the executable file might be covered by the GNU General
29 // Public License.
30 
31 // Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
32 
33 // Permission to use, copy, modify, sell, and distribute this software
34 // is hereby granted without fee, provided that the above copyright
35 // notice appears in all copies, and that both that copyright notice
36 // and this permission notice appear in supporting documentation. None
37 // of the above authors, nor IBM Haifa Research Laboratories, make any
38 // representation about the suitability of this software for any
39 // purpose. It is provided "as is" without express or implied
40 // warranty.
41 
42 /** @file ext/vstring.h
43  *  This file is a GNU extension to the Standard C++ Library.
44  *
45  *  Contains an exception-throwing allocator, useful for testing
46  *  exception safety. In addition, allocation addresses are stored and
47  *  sanity checked.
48  */
49 
50 /**
51  * @file throw_allocator.h
52  */
53 
54 #ifndef _THROW_ALLOCATOR_H
55 #define _THROW_ALLOCATOR_H 1
56 
57 #include <cmath>
58 #include <map>
59 #include <set>
60 #include <string>
61 #include <ostream>
62 #include <stdexcept>
63 #include <utility>
64 #include <tr1/random>
65 #include <bits/functexcept.h>
66 
_GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)67 _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)
68 
69   class twister_rand_gen
70   {
71   public:
72     twister_rand_gen(unsigned int seed =
73 		     static_cast<unsigned int>(std::time(0)));
74 
75     void
76     init(unsigned int);
77 
78     double
79     get_prob();
80 
81   private:
82     std::tr1::mt19937 _M_generator;
83   };
84 
85   struct forced_exception_error : public std::exception
86   { };
87 
88   // Substitute for concurrence_error object in the case of -fno-exceptions.
89   inline void
__throw_forced_exception_error()90   __throw_forced_exception_error()
91   {
92 #if __EXCEPTIONS
93     throw forced_exception_error();
94 #else
95     __builtin_abort();
96 #endif
97   }
98 
99   class throw_allocator_base
100   {
101   public:
102     void
103     init(unsigned long seed);
104 
105     static void
106     set_throw_prob(double throw_prob);
107 
108     static double
109     get_throw_prob();
110 
111     static void
112     set_label(size_t l);
113 
114     static bool
115     empty();
116 
117     struct group_throw_prob_adjustor
118     {
group_throw_prob_adjustorgroup_throw_prob_adjustor119       group_throw_prob_adjustor(size_t size)
120       : _M_throw_prob_orig(_S_throw_prob)
121       {
122 	_S_throw_prob =
123 	  1 - ::pow(double(1 - _S_throw_prob), double(0.5 / (size + 1)));
124       }
125 
~group_throw_prob_adjustorgroup_throw_prob_adjustor126       ~group_throw_prob_adjustor()
127       { _S_throw_prob = _M_throw_prob_orig; }
128 
129     private:
130       const double _M_throw_prob_orig;
131     };
132 
133     struct zero_throw_prob_adjustor
134     {
zero_throw_prob_adjustorzero_throw_prob_adjustor135       zero_throw_prob_adjustor() : _M_throw_prob_orig(_S_throw_prob)
136       { _S_throw_prob = 0; }
137 
~zero_throw_prob_adjustorzero_throw_prob_adjustor138       ~zero_throw_prob_adjustor()
139       { _S_throw_prob = _M_throw_prob_orig; }
140 
141     private:
142       const double _M_throw_prob_orig;
143     };
144 
145   protected:
146     static void
147     insert(void*, size_t);
148 
149     static void
150     erase(void*, size_t);
151 
152     static void
153     throw_conditionally();
154 
155     // See if a particular address and size has been allocated by this
156     // allocator.
157     static void
158     check_allocated(void*, size_t);
159 
160     // See if a given label has been allocated by this allocator.
161     static void
162     check_allocated(size_t);
163 
164   private:
165     typedef std::pair<size_t, size_t> 		alloc_data_type;
166     typedef std::map<void*, alloc_data_type> 	map_type;
167     typedef map_type::value_type 		entry_type;
168     typedef map_type::const_iterator 		const_iterator;
169     typedef map_type::const_reference 		const_reference;
170 
171     friend std::ostream&
172     operator<<(std::ostream&, const throw_allocator_base&);
173 
174     static entry_type
175     make_entry(void*, size_t);
176 
177     static void
178     print_to_string(std::string&);
179 
180     static void
181     print_to_string(std::string&, const_reference);
182 
183     static twister_rand_gen 	_S_g;
184     static map_type 		_S_map;
185     static double 		_S_throw_prob;
186     static size_t 		_S_label;
187   };
188 
189 
190   template<typename T>
191     class throw_allocator : public throw_allocator_base
192     {
193     public:
194       typedef size_t 				size_type;
195       typedef ptrdiff_t 			difference_type;
196       typedef T 				value_type;
197       typedef value_type* 			pointer;
198       typedef const value_type* 		const_pointer;
199       typedef value_type& 			reference;
200       typedef const value_type& 		const_reference;
201 
202 
203       template<typename U>
204       struct rebind
205       {
206         typedef throw_allocator<U> other;
207       };
208 
throw()209       throw_allocator() throw() { }
210 
throw()211       throw_allocator(const throw_allocator&) throw() { }
212 
213       template<typename U>
throw_allocator(const throw_allocator<U> &)214       throw_allocator(const throw_allocator<U>&) throw() { }
215 
throw()216       ~throw_allocator() throw() { }
217 
218       size_type
max_size()219       max_size() const throw()
220       { return std::allocator<value_type>().max_size(); }
221 
222       pointer
223       allocate(size_type num, std::allocator<void>::const_pointer hint = 0)
224       {
225 	throw_conditionally();
226 	value_type* const a = std::allocator<value_type>().allocate(num, hint);
227 	insert(a, sizeof(value_type) * num);
228 	return a;
229       }
230 
231       void
construct(pointer p,const T & val)232       construct(pointer p, const T& val)
233       { return std::allocator<value_type>().construct(p, val); }
234 
235       void
destroy(pointer p)236       destroy(pointer p)
237       { std::allocator<value_type>().destroy(p); }
238 
239       void
deallocate(pointer p,size_type num)240       deallocate(pointer p, size_type num)
241       {
242 	erase(p, sizeof(value_type) * num);
243 	std::allocator<value_type>().deallocate(p, num);
244       }
245 
246       void
check_allocated(pointer p,size_type num)247       check_allocated(pointer p, size_type num)
248       { throw_allocator_base::check_allocated(p, sizeof(value_type) * num); }
249 
250       void
check_allocated(size_type label)251       check_allocated(size_type label)
252       { throw_allocator_base::check_allocated(label); }
253     };
254 
255   template<typename T>
256     inline bool
257     operator==(const throw_allocator<T>&, const throw_allocator<T>&)
258     { return true; }
259 
260   template<typename T>
261     inline bool
262     operator!=(const throw_allocator<T>&, const throw_allocator<T>&)
263     { return false; }
264 
265   std::ostream&
266   operator<<(std::ostream& os, const throw_allocator_base& alloc)
267   {
268     std::string error;
269     throw_allocator_base::print_to_string(error);
270     os << error;
271     return os;
272   }
273 
274   // XXX Should be in .cc.
275   twister_rand_gen::
twister_rand_gen(unsigned int seed)276   twister_rand_gen(unsigned int seed) : _M_generator(seed)  { }
277 
278   void
279   twister_rand_gen::
init(unsigned int seed)280   init(unsigned int seed)
281   { _M_generator.seed(seed); }
282 
283   double
284   twister_rand_gen::
get_prob()285   get_prob()
286   {
287     const double eng_min = _M_generator.min();
288     const double eng_range =
289       static_cast<const double>(_M_generator.max() - eng_min);
290 
291     const double eng_res =
292       static_cast<const double>(_M_generator() - eng_min);
293 
294     const double ret = eng_res / eng_range;
295     _GLIBCXX_DEBUG_ASSERT(ret >= 0 && ret <= 1);
296     return ret;
297   }
298 
299   twister_rand_gen throw_allocator_base::_S_g;
300 
301   throw_allocator_base::map_type
302   throw_allocator_base::_S_map;
303 
304   double throw_allocator_base::_S_throw_prob;
305 
306   size_t throw_allocator_base::_S_label = 0;
307 
308   throw_allocator_base::entry_type
make_entry(void * p,size_t size)309   throw_allocator_base::make_entry(void* p, size_t size)
310   { return std::make_pair(p, alloc_data_type(_S_label, size)); }
311 
312   void
init(unsigned long seed)313   throw_allocator_base::init(unsigned long seed)
314   { _S_g.init(seed); }
315 
316   void
set_throw_prob(double throw_prob)317   throw_allocator_base::set_throw_prob(double throw_prob)
318   { _S_throw_prob = throw_prob; }
319 
320   double
get_throw_prob()321   throw_allocator_base::get_throw_prob()
322   { return _S_throw_prob; }
323 
324   void
set_label(size_t l)325   throw_allocator_base::set_label(size_t l)
326   { _S_label = l; }
327 
328   void
insert(void * p,size_t size)329   throw_allocator_base::insert(void* p, size_t size)
330   {
331     const_iterator found_it = _S_map.find(p);
332     if (found_it != _S_map.end())
333       {
334 	std::string error("throw_allocator_base::insert");
335 	error += "double insert!";
336 	error += '\n';
337 	print_to_string(error, make_entry(p, size));
338 	print_to_string(error, *found_it);
339 	std::__throw_logic_error(error.c_str());
340       }
341     _S_map.insert(make_entry(p, size));
342   }
343 
344   bool
empty()345   throw_allocator_base::empty()
346   { return _S_map.empty(); }
347 
348   void
erase(void * p,size_t size)349   throw_allocator_base::erase(void* p, size_t size)
350   {
351     check_allocated(p, size);
352     _S_map.erase(p);
353   }
354 
355   void
check_allocated(void * p,size_t size)356   throw_allocator_base::check_allocated(void* p, size_t size)
357   {
358     const_iterator found_it = _S_map.find(p);
359     if (found_it == _S_map.end())
360       {
361 	std::string error("throw_allocator_base::check_allocated by value ");
362 	error += "null erase!";
363 	error += '\n';
364 	print_to_string(error, make_entry(p, size));
365 	std::__throw_logic_error(error.c_str());
366       }
367 
368     if (found_it->second.second != size)
369       {
370 	std::string error("throw_allocator_base::check_allocated by value ");
371 	error += "wrong-size erase!";
372 	error += '\n';
373 	print_to_string(error, make_entry(p, size));
374 	print_to_string(error, *found_it);
375 	std::__throw_logic_error(error.c_str());
376       }
377   }
378 
379   void
check_allocated(size_t label)380   throw_allocator_base::check_allocated(size_t label)
381   {
382     std::string found;
383     const_iterator it = _S_map.begin();
384     while (it != _S_map.end())
385       {
386 	if (it->second.first == label)
387 	  print_to_string(found, *it);
388 	++it;
389       }
390 
391     if (!found.empty())
392       {
393 	std::string error("throw_allocator_base::check_allocated by label ");
394 	error += '\n';
395 	error += found;
396 	std::__throw_logic_error(error.c_str());
397       }
398   }
399 
400   void
throw_conditionally()401   throw_allocator_base::throw_conditionally()
402   {
403     if (_S_g.get_prob() < _S_throw_prob)
404       __throw_forced_exception_error();
405   }
406 
407   void
print_to_string(std::string & s)408   throw_allocator_base::print_to_string(std::string& s)
409   {
410     const_iterator begin = throw_allocator_base::_S_map.begin();
411     const_iterator end = throw_allocator_base::_S_map.end();
412     for (; begin != end; ++begin)
413       print_to_string(s, *begin);
414   }
415 
416   void
print_to_string(std::string & s,const_reference ref)417   throw_allocator_base::print_to_string(std::string& s, const_reference ref)
418   {
419     char buf[40];
420     const char tab('\t');
421     s += "address: ";
422     snprintf(buf, sizeof buf, "%p", ref.first);
423     s += buf;
424     s += tab;
425     s += "label: ";
426     snprintf(buf, sizeof buf, "%u", ref.second.first);
427     s += buf;
428     s += tab;
429     s += "size: ";
430     snprintf(buf, sizeof buf, "%u", ref.second.second);
431     s += buf;
432     s += '\n';
433   }
434 
435 _GLIBCXX_END_NAMESPACE
436 
437 #endif
438