/**
 * @file   cuda_wrapper.h
 * @author Martin Pulec     <pulec@cesnet.cz>
 *
 * @brief  This file contais wrapper around CUDA functions.
 */
/*
 * Copyright (c) 2013 CESNET z.s.p.o.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, is permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions 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.
 *
 * 3. Neither the name of CESNET nor the names of its contributors may be
 *    used to endorse or promote products derived from this software without
 *    specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESSED 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 AUTHORS 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.
 */

#include "cuda_wrapper.h"

#include "cuda_runtime.h"
#include <stdlib.h>

typedef void *cuda_wrapper_stream_t;

static inline int map_cuda_error(cudaError_t cuda_error) {
        return (int) cuda_error;
};

static inline const char * map_error_string(int error) {

        return cudaGetErrorString((cudaError_t) error);
};

static inline enum cudaMemcpyKind map_cuda_memcpy_kind(int our_kind) {
        struct kind_mapping {
                enum cudaMemcpyKind kind;
                int our_kind;
        };
        struct kind_mapping mapping[] = {
                { cudaMemcpyHostToDevice, CUDA_WRAPPER_MEMCPY_HOST_TO_DEVICE },
                { cudaMemcpyDeviceToHost, CUDA_WRAPPER_MEMCPY_DEVICE_TO_HOST },
        };

        int i;
        for (i = 0; i < sizeof(mapping)/sizeof(struct kind_mapping); ++i) {
                if (our_kind == mapping[i].our_kind) {
                        return mapping[i].kind;
                }
        }

        abort(); // should not reach here
};

CUDA_DLL_API int cuda_wrapper_free(void *buffer)
{
        return map_cuda_error(cudaFree(buffer));
}

CUDA_DLL_API int cuda_wrapper_free_host(void *buffer)
{
        return map_cuda_error(cudaFreeHost(buffer));
}

CUDA_DLL_API int cuda_wrapper_host_alloc(void **pHost, size_t size, unsigned int flags)
{
        return map_cuda_error(cudaHostAlloc(pHost, size, flags));
}

CUDA_DLL_API int cuda_wrapper_malloc(void **buffer, size_t data_len)
{
        return map_cuda_error(cudaMalloc(buffer, data_len));
}

CUDA_DLL_API int cuda_wrapper_malloc_host(void **buffer, size_t data_len)
{
        return map_cuda_error(cudaMallocHost(buffer, data_len));
}

CUDA_DLL_API int cuda_wrapper_memcpy(void *dst, const void *src,
                size_t count, int kind)
{
        return map_cuda_error(
                        cudaMemcpy(dst, src, count,
                                map_cuda_memcpy_kind(kind)));
}

CUDA_DLL_API const char *cuda_wrapper_last_error_string(void)
{
        return cudaGetErrorString(cudaGetLastError());
}

CUDA_DLL_API int cuda_wrapper_get_last_error(void)
{
        return map_cuda_error(cudaGetLastError());
}

CUDA_DLL_API const char *cuda_wrapper_get_error_string(int error)
{
        return map_error_string(error);
}

CUDA_DLL_API int cuda_wrapper_set_device(int index)
{
        return map_cuda_error(
                        cudaSetDevice(index));
}