/*
    Copyright 2005-2010 Intel Corporation.  All Rights Reserved.

    This file is part of Threading Building Blocks.

    Threading Building Blocks is free software; you can redistribute it
    and/or modify it under the terms of the GNU General Public License
    version 2 as published by the Free Software Foundation.

    Threading Building Blocks 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 Threading Building Blocks; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    As a special exception, you may use this file as part of a free software
    library without restriction.  Specifically, if other files instantiate
    templates or use macros or inline functions from this file, or you compile
    this file and link it with other files to produce an executable, this
    file does not by itself cause the resulting executable to be covered by
    the GNU General Public License.  This exception does not however
    invalidate any other reasons why the executable file might be covered by
    the GNU General Public License.
*/

// Basic testing of an allocator
// Tests against requirements in 20.1.5 of ISO C++ Standard (1998).
// Does not check for thread safety or false sharing issues.
//
// Tests for compatibility with the host's STL are in 
// test_Allocator_STL.h.  Those tests are in a separate file
// because they bring in lots of STL headers, and the tests here
// are supposed to work in the abscense of STL.

#include "harness.h"

template<typename A>
struct is_zero_filling {
    static const bool value = false;
};

int NumberOfFoo;

template<typename T, size_t N>
struct Foo {
    T foo_array[N];
    Foo() {
        zero_fill<T>(foo_array, N);
        ++NumberOfFoo;
    }
    Foo( const Foo& x ) {
        *this = x;
        ++NumberOfFoo;
    }
    ~Foo() {
        --NumberOfFoo;
    }
};

inline char PseudoRandomValue( size_t j, size_t k ) {
    return char(j*3 ^ j>>4 ^ k);
}

//! T is type and A is allocator for that type 
template<typename T, typename A>
void TestBasic( A& a ) {
    T x;
    const T cx = T();

    // See Table 32 in ISO ++ Standard
    typename A::pointer px = &x;
    typename A::const_pointer pcx = &cx;

    typename A::reference rx = x;
    ASSERT( &rx==&x, NULL );

    typename A::const_reference rcx = cx;
    ASSERT( &rcx==&cx, NULL );

    typename A::value_type v = x;

    typename A::size_type size;
    size = 0;
    --size;
    ASSERT( size>0, "not an unsigned integral type?" );

    typename A::difference_type difference;
    difference = 0;
    --difference;
    ASSERT( difference<0, "not an signed integral type?" );

    // "rebind" tested by our caller 

    ASSERT( a.address(rx)==px, NULL );

    ASSERT( a.address(rcx)==pcx, NULL );

    typename A::pointer array[100];
    size_t sizeof_T = sizeof(T);
    for( size_t k=0; k<100; ++k ) {
        array[k] = k&1 ? a.allocate(k,array[0]) : a.allocate(k);
        char* s = reinterpret_cast<char*>(reinterpret_cast<void*>(array[k]));
        for( size_t j=0; j<k*sizeof_T; ++j )
            s[j] = PseudoRandomValue(j,k);
    }

    // Test hint argument. This can't be compiled when hint is void*, It should be const void*
    typename A::pointer a_ptr;
    const void * const_hint = NULL;    
    a_ptr = a.allocate (1, const_hint);    
    a.deallocate(a_ptr, 1);

    // Test "a.deallocate(p,n)
    for( size_t k=0; k<100; ++k ) {
        char* s = reinterpret_cast<char*>(reinterpret_cast<void*>(array[k]));
        for( size_t j=0; j<k*sizeof_T; ++j )
            ASSERT( s[j] == PseudoRandomValue(j,k), NULL );
        a.deallocate(array[k],k);
    }

    // Test "a.max_size()"
    AssertSameType( a.max_size(), typename A::size_type(0) );
    // Following assertion catches case where max_size() is so large that computation of 
    // number of bytes for such an allocation would overflow size_type.
    ASSERT( a.max_size()*typename A::size_type(sizeof(T))>=a.max_size(), "max_size larger than reasonable" ); 

    // Test "a1==a2"
    A a1, a2;
    ASSERT( a1==a2, NULL );

    // Test "a1!=a2"
    ASSERT( !(a1!=a2), NULL );

    // Test "a.construct(p,t)"
    int n = NumberOfFoo;
    typename A::pointer p = a.allocate(1);
    a.construct( p, cx );
    ASSERT( NumberOfFoo==n+1, "constructor for Foo not called?" );

    // Test "a.destroy(p)"
    a.destroy( p );
    ASSERT( NumberOfFoo==n, "destructor for Foo not called?" );
    a.deallocate(p,1);
}

#include "tbb/blocked_range.h"

#if _MSC_VER && !defined(__INTEL_COMPILER)
    // Workaround for erroneous "conditional expression is constant" warning in method check_allocate.
    #pragma warning (disable: 4127)
#endif

// A is an allocator for some type
template<typename A>
struct Body: NoAssign {
    static const size_t max_k = 100000;
    A &a;
    Body(A &a_) : a(a_) {}
    void check_allocate( typename A::pointer array[], size_t i, size_t t ) const
    {
        ASSERT(array[i] == 0, NULL);
        size_t size = i * (i&3);
        array[i] = i&1 ? a.allocate(size, array[i>>3]) : a.allocate(size);
        char* s = reinterpret_cast<char*>(reinterpret_cast<void*>(array[i]));
        for( size_t j=0; j<size*sizeof(A); ++j ) {
            if(is_zero_filling<typename A::template rebind<void>::other>::value)
                ASSERT( !s[j], NULL);
            s[j] = PseudoRandomValue(i, t);
        }
    }

    void check_deallocate( typename A::pointer array[], size_t i, size_t t ) const
    {
        ASSERT(array[i] != 0, NULL);
        size_t size = i * (i&3);
        char* s = reinterpret_cast<char*>(reinterpret_cast<void*>(array[i]));
        for( size_t j=0; j<size*sizeof(A); ++j )
            ASSERT( s[j] == PseudoRandomValue(i, t), "Thread safety test failed" );
        a.deallocate(array[i], size);
        array[i] = 0;
    }

    void operator()( size_t thread_id ) const {
        typename A::pointer array[256];

        for( size_t k=0; k<256; ++k )
            array[k] = 0;
        for( size_t k=0; k<max_k; ++k ) {
            size_t i = static_cast<unsigned char>(PseudoRandomValue(k,thread_id));
            if(!array[i]) check_allocate(array, i, thread_id);
            else check_deallocate(array, i, thread_id);
        }
        for( size_t k=0; k<256; ++k )
            if(array[k])
                check_deallocate(array, k, thread_id);
    }
};

// A is an allocator for some type, and U is another type
template<typename A, typename U>
void Test() {
    typename A::template rebind<U>::other b;
    TestBasic<U>(b);

    A a(b);
    TestBasic<typename A::value_type>(a);

    // thread safety
    int n = NumberOfFoo;
    NativeParallelFor( 4, Body<A>(a) );
    ASSERT( NumberOfFoo==n, "Allocate/deallocate count mismatched" );
 
    ASSERT( a==b, NULL );
    ASSERT( !(a!=b), NULL );
}

template<typename Allocator>
int TestMain() {
    Test<typename Allocator::template rebind<Foo<char,1> >::other, Foo<int,17> >();
    Test<typename Allocator::template rebind<Foo<double,1> >::other, Foo<float,23> >();
    return 0;
}