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// { dg-timeout-factor 2.0 }
// -*- C++ -*-
// Copyright (C) 2005-2016 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library 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 3, or (at your option) any later
// version.
// This library 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 this library; see the file COPYING3. If not see
// <http://www.gnu.org/licenses/>.
// Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
// Permission to use, copy, modify, sell, and distribute this software
// is hereby granted without fee, provided that the above copyright
// notice appears in all copies, and that both that copyright notice
// and this permission notice appear in supporting documentation. None
// of the above authors, nor IBM Haifa Research Laboratories, make any
// representation about the suitability of this software for any
// purpose. It is provided "as is" without express or implied
// warranty.
/**
* @file hash_illegal_resize_example.cpp
* An example of illegally externally resizing a hash-based container object.
*/
/**
* This example shows the case where a hash-based container object is
* resized to a value which it cannot accommodate at runtime. Illegal
* runtime resizes cause an exception.
*/
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/hash_policy.hpp>
#include <ext/pb_ds/exception.hpp>
#include <cassert>
// size of test containers
#ifdef _GLIBCXX_DEBUG
# define SIZE 100
# define RESIZE 20
#else
# define SIZE 1000
# define RESIZE 200
#endif
using namespace std;
using namespace __gnu_pbds;
// A simple hash functor.
// hash could serve instead of this functor, but it is not yet
// standard everywhere.
struct int_hash : public unary_function<int, size_t>
{
inline size_t
operator()(const int& r_i) const
{ return r_i; }
};
int main()
{
// A probing hash table mapping ints to chars.
typedef
gp_hash_table<
int,
int,
int_hash,
equal_to<int>,
// Combining function.
direct_mod_range_hashing<>,
// Probe function.
quadratic_probe_fn<>,
// Resize policy.
hash_standard_resize_policy<
hash_prime_size_policy,
hash_load_check_resize_trigger<>,
/* Allow external access to size.
* Without setting this to true, external resizing
* is not possible.
*/
true> >
map_t;
map_t g;
// Insert some elements.
int i;
for (i = 0; i < SIZE; ++i)
g[i] = 2* i;
// Check all ok.
assert(g.size() == SIZE);
for (i = 0; i < SIZE; ++i)
assert(g.find(i) != g.end() && g.find(i)->second == 2 * i);
// Now attempt to resize the table to 200 (impossible).
bool ex_thrown = false;
try
{
g.resize(RESIZE);
}
catch(__gnu_pbds::resize_error& )
{
ex_thrown = true;
}
// Assert an exception was thrown. A probing table cannot contain
// 1000 entries in less than 1000 places.
assert(ex_thrown);
// Irrespective of the fact that the resize was not successful, the
// container object should still be in a valid state; the following
// checks this.
// Check all ok.
assert(g.size() == SIZE);
for (i = 0; i < SIZE; ++i)
assert(g.find(i) != g.end() && g.find(i)->second == 2 * i);
return 0;
}
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