/*M///////////////////////////////////////////////////////////////////////////////////////
//
//  IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING.
//
//  By downloading, copying, installing or using the software you agree to this license.
//  If you do not agree to this license, do not download, install,
//  copy or use the software.
//
//
//                          License Agreement
//                For Open Source Computer Vision Library
//
// Copyright (C) 2000-2008, Intel Corporation, all rights reserved.
// Copyright (C) 2009, Willow Garage Inc., all rights reserved.
// Copyright (C) 2013, OpenCV Foundation, all rights reserved.
// Third party copyrights are property of their respective owners.
//
// Redistribution and use in source and binary forms, with or without modification,
// are permitted provided that the following conditions are met:
//
//   * Redistribution's of source code must retain the above copyright notice,
//     this list of conditions and the following disclaimer.
//
//   * Redistribution's in binary form must reproduce the above copyright notice,
//     this list of conditions and the following disclaimer in the documentation
//     and/or other materials provided with the distribution.
//
//   * The name of the copyright holders may not be used to endorse or promote products
//     derived from this software without specific prior written permission.
//
// This software is provided by the copyright holders and contributors "as is" and
// any express or implied warranties, including, but not limited to, the implied
// warranties of merchantability and fitness for a particular purpose are disclaimed.
// In no event shall the Intel Corporation or contributors be liable for any direct,
// indirect, incidental, special, exemplary, or consequential damages
// (including, but not limited to, procurement of substitute goods or services;
// loss of use, data, or profits; or business interruption) however caused
// and on any theory of liability, whether in contract, strict liability,
// or tort (including negligence or otherwise) arising in any way out of
// the use of this software, even if advised of the possibility of such damage.
//
//M*/

#include "precomp.hpp"

using namespace cv;
using namespace cv::cuda;

#ifdef HAVE_CUDA
namespace
{
    size_t alignUpStep(size_t what, size_t alignment)
    {
        size_t alignMask = alignment - 1;
        size_t inverseAlignMask = ~alignMask;
        size_t res = (what + alignMask) & inverseAlignMask;
        return res;
    }
}
#endif

void cv::cuda::CudaMem::create(int rows_, int cols_, int type_)
{
#ifndef HAVE_CUDA
    (void) rows_;
    (void) cols_;
    (void) type_;
    throw_no_cuda();
#else
    if (alloc_type == SHARED)
    {
        DeviceInfo devInfo;
        CV_Assert( devInfo.canMapHostMemory() );
    }

    type_ &= Mat::TYPE_MASK;

    if (rows == rows_ && cols == cols_ && type() == type_ && data)
        return;

    if (data)
        release();

    CV_DbgAssert( rows_ >= 0 && cols_ >= 0 );

    if (rows_ > 0 && cols_ > 0)
    {
        flags = Mat::MAGIC_VAL + Mat::CONTINUOUS_FLAG + type_;
        rows = rows_;
        cols = cols_;
        step = elemSize() * cols;

        if (alloc_type == SHARED)
        {
            DeviceInfo devInfo;
            step = alignUpStep(step, devInfo.textureAlignment());
        }

        int64 _nettosize = (int64)step*rows;
        size_t nettosize = (size_t)_nettosize;

        if (_nettosize != (int64)nettosize)
            CV_Error(cv::Error::StsNoMem, "Too big buffer is allocated");

        size_t datasize = alignSize(nettosize, (int)sizeof(*refcount));

        void* ptr = 0;

        switch (alloc_type)
        {
        case PAGE_LOCKED:    cudaSafeCall( cudaHostAlloc(&ptr, datasize, cudaHostAllocDefault) ); break;
        case SHARED:         cudaSafeCall( cudaHostAlloc(&ptr, datasize, cudaHostAllocMapped) );  break;
        case WRITE_COMBINED: cudaSafeCall( cudaHostAlloc(&ptr, datasize, cudaHostAllocWriteCombined) ); break;
        default:             CV_Error(cv::Error::StsBadFlag, "Invalid alloc type");
        }

        datastart = data =  (uchar*)ptr;
        dataend = data + nettosize;

        refcount = (int*)cv::fastMalloc(sizeof(*refcount));
        *refcount = 1;
    }
#endif
}

CudaMem cv::cuda::CudaMem::reshape(int new_cn, int new_rows) const
{
    CudaMem hdr = *this;

    int cn = channels();
    if (new_cn == 0)
        new_cn = cn;

    int total_width = cols * cn;

    if ((new_cn > total_width || total_width % new_cn != 0) && new_rows == 0)
        new_rows = rows * total_width / new_cn;

    if (new_rows != 0 && new_rows != rows)
    {
        int total_size = total_width * rows;

        if (!isContinuous())
            CV_Error(cv::Error::BadStep, "The matrix is not continuous, thus its number of rows can not be changed");

        if ((unsigned)new_rows > (unsigned)total_size)
            CV_Error(cv::Error::StsOutOfRange, "Bad new number of rows");

        total_width = total_size / new_rows;

        if (total_width * new_rows != total_size)
            CV_Error(cv::Error::StsBadArg, "The total number of matrix elements is not divisible by the new number of rows");

        hdr.rows = new_rows;
        hdr.step = total_width * elemSize1();
    }

    int new_width = total_width / new_cn;

    if (new_width * new_cn != total_width)
        CV_Error(cv::Error::BadNumChannels, "The total width is not divisible by the new number of channels");

    hdr.cols = new_width;
    hdr.flags = (hdr.flags & ~CV_MAT_CN_MASK) | ((new_cn - 1) << CV_CN_SHIFT);

    return hdr;
}

void cv::cuda::CudaMem::release()
{
#ifdef HAVE_CUDA
    if (refcount && CV_XADD(refcount, -1) == 1)
    {
        cudaFreeHost(datastart);
        fastFree(refcount);
    }

    dataend = data = datastart = 0;
    step = rows = cols = 0;
    refcount = 0;
#endif
}

GpuMat cv::cuda::CudaMem::createGpuMatHeader() const
{
#ifndef HAVE_CUDA
    throw_no_cuda();
    return GpuMat();
#else
    CV_Assert( alloc_type == SHARED );

    void *pdev;
    cudaSafeCall( cudaHostGetDevicePointer(&pdev, data, 0) );

    return GpuMat(rows, cols, type(), pdev, step);
#endif
}

void cv::cuda::registerPageLocked(Mat& m)
{
#ifndef HAVE_CUDA
    (void) m;
    throw_no_cuda();
#else
    CV_Assert( m.isContinuous() );
    cudaSafeCall( cudaHostRegister(m.data, m.step * m.rows, cudaHostRegisterPortable) );
#endif
}

void cv::cuda::unregisterPageLocked(Mat& m)
{
#ifndef HAVE_CUDA
    (void) m;
#else
    cudaSafeCall( cudaHostUnregister(m.data) );
#endif
}