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// Copyright 2025 Peter Dimov
// Distributed under the Boost Software License, Version 1.0.
// https://www.boost.org/LICENSE_1_0.txt
#include <boost/smart_ptr/detail/quick_allocator.hpp>
#include <boost/core/lightweight_test.hpp>
#include <cstring>
// The interface of quick_allocator has never been documented,
// but in can be inferred from the source code to be
//
// template<class T> struct quick_allocator
// {
// // allocate memory for an object of type T
// static void* alloc();
//
// // deallocate the memory returned from alloc()
// // if p == 0, no effect
// static void dealloc( void* p );
//
// // if n == sizeof(T), returns alloc()
// // otherwise, allocates a memory block of size n
// static void* alloc( std::size_t n );
//
// // deallocate the memory returned from alloc( n )
// // if p == 0, no effect
// static void dealloc( void* p, std::size_t n );
// };
struct X
{
int data;
};
struct Y: public X
{
int data2;
};
int main()
{
using boost::detail::quick_allocator;
void* p = quick_allocator<Y>::alloc();
std::memset( p, 0xAA, sizeof(Y) );
{
void* p1 = quick_allocator<X>::alloc();
std::memset( p1, 0xCC, sizeof(X) );
void* p2 = quick_allocator<X>::alloc();
std::memset( p2, 0xDD, sizeof(X) );
BOOST_TEST_NE( p1, p2 );
BOOST_TEST_EQ( *static_cast<unsigned char*>( p1 ), 0xCC );
BOOST_TEST_EQ( *static_cast<unsigned char*>( p2 ), 0xDD );
quick_allocator<X>::dealloc( 0 );
BOOST_TEST_EQ( *static_cast<unsigned char*>( p1 ), 0xCC );
BOOST_TEST_EQ( *static_cast<unsigned char*>( p2 ), 0xDD );
quick_allocator<X>::dealloc( p1 );
BOOST_TEST_EQ( *static_cast<unsigned char*>( p2 ), 0xDD );
quick_allocator<X>::dealloc( p2 );
}
{
void* p1 = quick_allocator<X>::alloc( sizeof(X) );
std::memset( p1, 0xCC, sizeof(X) );
void* p2 = quick_allocator<X>::alloc( sizeof(Y) );
std::memset( p2, 0xDD, sizeof(Y) );
BOOST_TEST_NE( p1, p2 );
BOOST_TEST_EQ( *static_cast<unsigned char*>( p1 ), 0xCC );
BOOST_TEST_EQ( *static_cast<unsigned char*>( p2 ), 0xDD );
quick_allocator<X>::dealloc( 0, sizeof(X) );
BOOST_TEST_EQ( *static_cast<unsigned char*>( p1 ), 0xCC );
BOOST_TEST_EQ( *static_cast<unsigned char*>( p2 ), 0xDD );
quick_allocator<X>::dealloc( p1, sizeof(X) );
BOOST_TEST_EQ( *static_cast<unsigned char*>( p2 ), 0xDD );
quick_allocator<X>::dealloc( 0, sizeof(Y) );
BOOST_TEST_EQ( *static_cast<unsigned char*>( p2 ), 0xDD );
quick_allocator<X>::dealloc( p2, sizeof(Y) );
}
BOOST_TEST_EQ( *static_cast<unsigned char*>( p ), 0xAA );
quick_allocator<Y>::dealloc( 0 );
BOOST_TEST_EQ( *static_cast<unsigned char*>( p ), 0xAA );
quick_allocator<Y>::dealloc( p );
return boost::report_errors();
}
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