/*
    Copyright (c) 2005-2020 Intel Corporation

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

        http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the 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"
#if __TBB_ALLOCATOR_CONSTRUCT_VARIADIC
    #include <utility> //for std::pair
#endif

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;
        //Internal call of assignment
    }
    Foo& operator=( const Foo& x ) {
        for (size_t i = 0; i < N; i++)
            foo_array[i] = x.foo_array[i];
        ++NumberOfFoo;
        return *this;
    }

    ~Foo() {
        --NumberOfFoo;
    }
};

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

#if __APPLE__
#include <fcntl.h>
#include <unistd.h>

// A RAII class to disable stderr in a certain scope. It's not thread-safe.
class DisableStderr {
    int stderrCopy;
    static void dupToStderrAndClose(int fd) {
        int ret = dup2(fd, STDERR_FILENO); // close current stderr
        ASSERT(ret != -1, NULL);
        ret = close(fd);
        ASSERT(ret != -1, NULL);
    }
public:
    DisableStderr() {
        int devNull = open("/dev/null", O_WRONLY);
        ASSERT(devNull != -1, NULL);
        stderrCopy = dup(STDERR_FILENO);
        ASSERT(stderrCopy != -1, NULL);
        dupToStderrAndClose(devNull);
    }
    ~DisableStderr() {
        dupToStderrAndClose(stderrCopy);
    }
};
#endif

//! 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 "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);

#if TBB_USE_EXCEPTIONS
    volatile size_t too_big = (~size_t(0) - 1024*1024)/sizeof(T);
    bool exception_caught = false;
    typename A::pointer p1 = NULL;
    try {
#if __APPLE__
        // On macOS*, failure to map memory results in messages to stderr;
        // suppress them.
        DisableStderr disableStderr;
#endif
        p1 = a.allocate(too_big);
    } catch ( std::bad_alloc& ) {
        exception_caught = true;
    }
    ASSERT( exception_caught, "allocate expected to throw bad_alloc" );
    a.deallocate(p1, too_big);
#endif // TBB_USE_EXCEPTIONS

    #if __TBB_ALLOCATOR_CONSTRUCT_VARIADIC
    {
        typedef typename A:: template rebind<std::pair<typename A::value_type, typename A::value_type> >::other pair_allocator_type;
        pair_allocator_type pair_allocator(a);
        int NumberOfFooBeforeConstruct= NumberOfFoo;
        typename pair_allocator_type::pointer pair_pointer = pair_allocator.allocate(1);
        pair_allocator.construct( pair_pointer, cx, cx);
        ASSERT( NumberOfFoo==NumberOfFooBeforeConstruct+2, "constructor for Foo not called appropriate number of times?" );

        pair_allocator.destroy( pair_pointer );
        ASSERT( NumberOfFoo==NumberOfFooBeforeConstruct, "destructor for Foo not called appropriate number of times?" );
        pair_allocator.deallocate(pair_pointer,1);
    }
    #endif

}

#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);
        ASSERT(array[i] != 0, "allocator returned null");
        char* s = reinterpret_cast<char*>(reinterpret_cast<void*>(array[i]));
        for( size_t j=0; j<size*sizeof(typename A::value_type); ++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(typename A::value_type); ++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 U, typename A>
void Test(A &a) {
    typename A::template rebind<U>::other b(a);
    TestBasic<U>(b);
    TestBasic<typename A::value_type>(a);

    // thread safety
    NativeParallelFor( 4, Body<A>(a) );
    ASSERT( NumberOfFoo==0, "Allocate/deallocate count mismatched" );

    ASSERT( a==b, NULL );
    ASSERT( !(a!=b), NULL );
}

template<typename Allocator>
int TestMain(const Allocator &a = Allocator()) {
    NumberOfFoo = 0;
    typename Allocator::template rebind<Foo<char,1> >::other a1(a);
    typename Allocator::template rebind<Foo<double,1> >::other a2(a);
    Test<Foo<int,17> >( a1 );
    Test<Foo<float,23> >( a2 );
    return 0;
}
