pgr_point_input.c

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/*PGR-GNU*****************************************************************
File: matrixRows_input.c
 
Copyright (c) 2015 Celia Virginia Vergara Castillo
[email protected]
 
------
 
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
 
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
 
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 
 ********************************************************************PGR-GNU*/
 
#include "c_common/pgr_point_input.h"
 
#include "c_common/debug_macro.h"
#include "c_common/get_check_data.h"
#include "c_common/time_msg.h"
 
 
 
static
void pgr_fetch_row(
        HeapTuple *tuple,
        TupleDesc *tupdesc,
        Column_info_t info[2],
        Pgr_point_t *point) {
    point->x = pgr_SPI_getFloat8(tuple, tupdesc,  info[0]);
    point->y = pgr_SPI_getFloat8(tuple, tupdesc, info[1]);
}
 
void pgr_point_input(
        char *points_sql,
        Pgr_point_t **points,
        size_t *pointsTotal) {
    clock_t start_t = clock();
 
    const int tuple_limit = 1000000;
 
    size_t total_tuples = 0;
 
    Column_info_t info[3];
 
    int i;
    for (i = 0; i < 2; ++i) {
        info[i].colNumber = -1;
        info[i].type = 0;
        info[i].strict = true;
        info[i].eType = ANY_NUMERICAL;
    }
    info[0].name = "x";
    info[1].name = "y";
 
 
    void *SPIplan;
    SPIplan = pgr_SPI_prepare(points_sql);
 
    Portal SPIportal;
    SPIportal = pgr_SPI_cursor_open(SPIplan);
 
 
    bool moredata = true;
    (*pointsTotal) = total_tuples;
 
    while (moredata == true) {
        SPI_cursor_fetch(SPIportal, true, tuple_limit);
        if (total_tuples == 0)
            pgr_fetch_column_info(info, 2);
 
        size_t ntuples = SPI_processed;
        total_tuples += ntuples;
 
        if (ntuples > 0) {
            if ((*points) == NULL)
                (*points) = (Pgr_point_t *)
                    palloc0(total_tuples * sizeof(Pgr_point_t));
            else
                (*points) = (Pgr_point_t *)
                    repalloc((*points),
                            total_tuples * sizeof(Pgr_point_t));
 
            if ((*points) == NULL) {
                elog(ERROR, "Out of memory");
            }
 
            SPITupleTable *tuptable = SPI_tuptable;
            TupleDesc tupdesc = SPI_tuptable->tupdesc;
 
            size_t t;
            for (t = 0; t < ntuples; t++) {
                HeapTuple tuple = tuptable->vals[t];
                pgr_fetch_row(&tuple, &tupdesc, info,
                        &(*points)[total_tuples - ntuples + t]);
            }
            SPI_freetuptable(tuptable);
        } else {
            moredata = false;
        }
    }
 
    SPI_cursor_close(SPIportal);
 
 
    if (total_tuples == 0) {
        (*pointsTotal) = 0;
        return;
    }
 
    (*pointsTotal) = total_tuples;
    time_msg(" reading points:", start_t, clock());
}