/* -*- Mode: C; c-basic-offset:4 ; indent-tabs-mode:nil ; -*- */
/*
 *
 *  (C) 2018 by Argonne National Laboratory.
 *      See COPYRIGHT in top-level directory.
 */

#ifndef DTPOOLS_H_INCLUDED
#define DTPOOLS_H_INCLUDED

/* errors */
#define DTP_SUCCESS   (0)
#define DTP_ERR_OTHER (1)

typedef enum {
    DTP_POOL_TYPE__BASIC,       /* basic type pool */
    DTP_POOL_TYPE__STRUCT,      /* struct type pool */
} DTP_pool_type;

/* MPI_DATATYPE_NULL terminated list of datatypes */
extern MPI_Datatype DTP_Basic_type[];

struct DTP_obj_array_s {
    MPI_Datatype DTP_obj_type;
    MPI_Aint DTP_obj_count;
    void *DTP_obj_buf;

    /* internal private structure to store datatype specific
     * information */
    void *private_info;
};

/* main DTP object */
typedef struct {
    DTP_pool_type DTP_pool_type;
    union {
        struct {
            MPI_Datatype DTP_basic_type;
            MPI_Aint DTP_basic_type_count;
        } DTP_pool_basic;
        struct {
            int DTP_num_types;
            MPI_Datatype *DTP_basic_type;
            int *DTP_basic_type_count;
        } DTP_pool_struct;
    } DTP_type_signature;

    int DTP_num_objs;
    struct DTP_obj_array_s *DTP_obj_array;
} *DTP_t;

/* DTP manipulation functions */
int DTP_pool_create(MPI_Datatype basic_type, MPI_Aint basic_type_count, DTP_t * dtp);
int DTP_pool_create_struct(int num_types, MPI_Datatype * basic_types, int *basic_type_counts,
                           DTP_t * dtp);
int DTP_pool_free(DTP_t dtp);
int DTP_obj_create(DTP_t dtp, int obj_idx, int val_start, int val_stride, MPI_Aint val_count);
int DTP_obj_free(DTP_t dtp, int obj_idx);
int DTP_obj_buf_check(DTP_t dtp, int obj_idx, int val_start, int val_stride, MPI_Aint val_count);

#endif /* DTPOOLS_H_INCLUDED */