/* -*- Mode: C; c-basic-offset:4 ; -*- */
/*
 * Copyright (c) 2004-2009 The University of Tennessee and The University
 *                         of Tennessee Research Foundation.  All rights
 *                         reserved.
 * Copyright (c) 2009      Oak Ridge National Labs.  All rights reserved.
 * $COPYRIGHT$
 *
 * Additional copyrights may follow
 *
 * $HEADER$
 */

#include "opal_config.h"

#include <stddef.h>

#include "opal/datatype/opal_datatype.h"
#include "opal/datatype/opal_convertor.h"
#include "opal/datatype/opal_datatype_internal.h"
#include "opal/datatype/opal_datatype_checksum.h"
#include "opal/datatype/opal_convertor_internal.h"

/*
 * This function is used to copy data from one buffer to another.  The assumption
 *     is that the number of bytes per element to copy at the source and destination
 *     are the same.
 *   count - number of instances of a given data-type to copy
 *   from - point to the source buffer
 *   to - pointer to the destination buffer
 *   from_len - length of source buffer (in bytes)
 *   to_len - length of destination buffer (in bytes)
 *   from_extent - extent of the source data type (in bytes)
 *   to_extent - extent of the destination data type (in bytes)
 *
 * Return value: Number of elements of type TYPE copied
 */
#define COPY_TYPE( TYPENAME, TYPE, COUNT )                                              \
static int copy_##TYPENAME( opal_convertor_t *pConvertor, uint32_t count,               \
                            char* from, size_t from_len, OPAL_PTRDIFF_TYPE from_extent, \
                            char* to, size_t to_len, OPAL_PTRDIFF_TYPE to_extent,       \
                            OPAL_PTRDIFF_TYPE *advance)                                 \
{                                                                                       \
    uint32_t i;                                                                         \
    size_t remote_TYPE_size = sizeof(TYPE) * (COUNT); /* TODO */                        \
    size_t local_TYPE_size = (COUNT) * sizeof(TYPE);                                    \
                                                                                        \
    /* make sure the remote buffer is large enough to hold the data */                  \
    if( (remote_TYPE_size * count) > from_len ) {                                       \
        count = (uint32_t)(from_len / remote_TYPE_size);                                \
        if( (count * remote_TYPE_size) != from_len ) {                                  \
            DUMP( "oops should I keep this data somewhere (excedent %d bytes)?\n",      \
                  from_len - (count * remote_TYPE_size) );                              \
        }                                                                               \
        DUMP( "correct: copy %s count %d from buffer %p with length %d to %p space %d\n", \
              #TYPE, count, from, from_len, to, to_len );                               \
    } else                                                                              \
        DUMP( "         copy %s count %d from buffer %p with length %d to %p space %d\n", \
              #TYPE, count, from, from_len, to, to_len );                               \
                                                                                        \
    if( (from_extent == (OPAL_PTRDIFF_TYPE)local_TYPE_size) &&                          \
        (to_extent == (OPAL_PTRDIFF_TYPE)remote_TYPE_size) ) {                          \
        /* copy of contigous data at both source and destination */                     \
        MEMCPY( to, from, count * local_TYPE_size );                                    \
    } else {                                                                            \
        /* source or destination are non-contigous */                                   \
        for( i = 0; i < count; i++ ) {                                                  \
            MEMCPY( to, from, local_TYPE_size );                                        \
            to += to_extent;                                                            \
            from += from_extent;                                                        \
        }                                                                               \
    }                                                                                   \
    *advance = count * from_extent;                                                     \
    return count;                                                                       \
}

/*
 * This function is used to copy data from one buffer to another.  The assumption
 *     is that the number of bytes per element to copy at the source and destination
 *     are the same.
 *   count - number of instances of a given data-type to copy
 *   from - point to the source buffer
 *   to - pointer to the destination buffer
 *   from_len - length of source buffer (in bytes)
 *   to_len - length of destination buffer (in bytes)
 *   from_extent - extent of the source data type (in bytes)
 *   to_extent - extent of the destination data type (in bytes)
 *
 * Return value: Number of elements of type TYPE copied
 */
#define COPY_CONTIGUOUS_BYTES( TYPENAME, COUNT )                                          \
static int copy_##TYPENAME##_##COUNT( opal_convertor_t *pConvertor, uint32_t count,       \
                                      char* from, size_t from_len, OPAL_PTRDIFF_TYPE from_extent, \
                                      char* to, size_t to_len, OPAL_PTRDIFF_TYPE to_extent,       \
                                      OPAL_PTRDIFF_TYPE *advance )              \
{                                                                               \
    uint32_t i;                                                                 \
    size_t remote_TYPE_size = (size_t)(COUNT); /* TODO */                       \
    size_t local_TYPE_size = (size_t)(COUNT);                                   \
                                                                                \
    if( (remote_TYPE_size * count) > from_len ) {                               \
        count = (uint32_t)(from_len / remote_TYPE_size);                        \
        if( (count * remote_TYPE_size) != from_len ) {                          \
            DUMP( "oops should I keep this data somewhere (excedent %d bytes)?\n", \
                  from_len - (count * remote_TYPE_size) );                      \
        }                                                                       \
        DUMP( "correct: copy %s count %d from buffer %p with length %d to %p space %d\n", \
              #TYPENAME, count, from, from_len, to, to_len );                   \
    } else                                                                      \
        DUMP( "         copy %s count %d from buffer %p with length %d to %p space %d\n", \
              #TYPENAME, count, from, from_len, to, to_len );                   \
                                                                                \
    if( (from_extent == (OPAL_PTRDIFF_TYPE)local_TYPE_size) &&                  \
        (to_extent == (OPAL_PTRDIFF_TYPE)remote_TYPE_size) ) {                  \
        MEMCPY( to, from, count * local_TYPE_size );                            \
    } else {                                                                    \
        for( i = 0; i < count; i++ ) {                                          \
            MEMCPY( to, from, local_TYPE_size );                                \
            to += to_extent;                                                    \
            from += from_extent;                                                \
        }                                                                       \
    }                                                                           \
    *advance = count * from_extent;                                             \
    return count;                                                               \
}

/* set up copy functions for the basic C MPI data types */
/* per default, select all of them */
#define REQUIRE_COPY_BYTES_1 1
#define REQUIRE_COPY_BYTES_2 1
#define REQUIRE_COPY_BYTES_4 1
#define REQUIRE_COPY_BYTES_8 1
#define REQUIRE_COPY_BYTES_16 1

#if REQUIRE_COPY_BYTES_1
COPY_CONTIGUOUS_BYTES( bytes, 1 )
#endif
#if REQUIRE_COPY_BYTES_2
COPY_CONTIGUOUS_BYTES( bytes, 2 )
#endif
#if REQUIRE_COPY_BYTES_4
COPY_CONTIGUOUS_BYTES( bytes, 4 )
#endif
#if REQUIRE_COPY_BYTES_8
COPY_CONTIGUOUS_BYTES( bytes, 8 )
#endif
#if REQUIRE_COPY_BYTES_16
COPY_CONTIGUOUS_BYTES( bytes, 16 )
#endif

#if SIZEOF_FLOAT == 2
COPY_TYPE( float_2, float, 1 )
#elif SIZEOF_DOUBLE == 2
COPY_TYPE( float_2, double, 1 )
#elif HAVE_LONG_DOUBLE && SIZEOF_LONG_DOUBLE == 2
COPY_TYPE( float_2, long double, 1 )
#else
/* #error No basic type for copy function for opal_datatype_float2 found */
#define copy_float_2 NULL
#endif

#if SIZEOF_FLOAT == 4
COPY_TYPE( float_4, float, 1 )
#elif SIZEOF_DOUBLE == 4
COPY_TYPE( float_4, double, 1 )
#elif HAVE_LONG_DOUBLE && SIZEOF_LONG_DOUBLE == 4
COPY_TYPE( float_4, long double, 1 )
#else
#error No basic type for copy function for opal_datatype_float4 found
#endif

#if SIZEOF_FLOAT == 8
COPY_TYPE( float_8, float, 1 )
#elif SIZEOF_DOUBLE == 8
COPY_TYPE( float_8, double, 1 )
#elif HAVE_LONG_DOUBLE && SIZEOF_LONG_DOUBLE == 8
COPY_TYPE( float_8, long double, 1 )
#else
#error No basic type for copy function for opal_datatype_float8 found
#endif

#if SIZEOF_FLOAT == 12
COPY_TYPE( float_12, float, 1 )
#elif SIZEOF_DOUBLE == 12
COPY_TYPE( float_12, double, 1 )
#elif HAVE_LONG_DOUBLE && SIZEOF_LONG_DOUBLE == 12
COPY_TYPE( float_12, long double, 1 )
#else
/* #error No basic type for copy function for opal_datatype_float12 found */
#define copy_float_12 NULL
#endif

#if SIZEOF_FLOAT == 16
COPY_TYPE( float_16, float, 1 )
#elif SIZEOF_DOUBLE == 16
COPY_TYPE( float_16, double, 1 )
#elif HAVE_LONG_DOUBLE && SIZEOF_LONG_DOUBLE == 16
COPY_TYPE( float_16, long double, 1 )
#else
/* #error No basic type for copy function for opal_datatype_float16 found */
#define copy_float_16 NULL
#endif

#if SIZEOF_BOOL == SIZEOF_CHAR
COPY_TYPE (bool, char, 1)
#elif SIZEOF_BOOL == SIZEOF_SHORT
COPY_TYPE (bool, short, 1)
#elif SIZEOF_BOOL == SIZEOF_INT
COPY_TYPE (bool, int, 1)
#elif SIZEOF_BOOL == SIZEOF_LONG
COPY_TYPE (bool, long, 1)
#else
#error No basic type for copy function for opal_datatype_bool found
#endif

COPY_TYPE (wchar, wchar_t, 1)


/* Table of predefined copy functions - one for each OPAL type */
/* NOTE: The order of this array *MUST* match the order in opal_datatype_basicDatatypes */
conversion_fct_t opal_datatype_copy_functions[OPAL_DATATYPE_MAX_PREDEFINED] = {
    (conversion_fct_t)NULL,                      /* OPAL_DATATYPE_LOOP         */
    (conversion_fct_t)NULL,                      /* OPAL_DATATYPE_END_LOOP     */
    (conversion_fct_t)NULL,                      /* OPAL_DATATYPE_LB           */
    (conversion_fct_t)NULL,                      /* OPAL_DATATYPE_UB           */
    (conversion_fct_t)copy_bytes_1,              /* OPAL_DATATYPE_INT1         */
    (conversion_fct_t)copy_bytes_2,              /* OPAL_DATATYPE_INT2         */
    (conversion_fct_t)copy_bytes_4,              /* OPAL_DATATYPE_INT4         */
    (conversion_fct_t)copy_bytes_8,              /* OPAL_DATATYPE_INT8         */
    (conversion_fct_t)copy_bytes_16,             /* OPAL_DATATYPE_INT16        */
    (conversion_fct_t)copy_bytes_1,              /* OPAL_DATATYPE_UINT1        */
    (conversion_fct_t)copy_bytes_2,              /* OPAL_DATATYPE_UINT2        */
    (conversion_fct_t)copy_bytes_4,              /* OPAL_DATATYPE_UINT4        */
    (conversion_fct_t)copy_bytes_8,              /* OPAL_DATATYPE_UINT8        */
    (conversion_fct_t)copy_bytes_16,             /* OPAL_DATATYPE_UINT16       */
    (conversion_fct_t)copy_float_2,              /* OPAL_DATATYPE_FLOAT2       */
    (conversion_fct_t)copy_float_4,              /* OPAL_DATATYPE_FLOAT4       */
    (conversion_fct_t)copy_float_8,              /* OPAL_DATATYPE_FLOAT8       */
    (conversion_fct_t)copy_float_12,             /* OPAL_DATATYPE_FLOAT12       */
    (conversion_fct_t)copy_float_16,             /* OPAL_DATATYPE_FLOAT16      */
    (conversion_fct_t)copy_bool,                 /* OPAL_DATATYPE_BOOL         */
    (conversion_fct_t)copy_wchar,                /* OPAL_DATATYPE_WCHAR        */
    (conversion_fct_t)NULL                       /* OPAL_DATATYPE_UNAVAILABLE  */
};
