analytics/informix/extend/TimeSeries.6.00.FC8/examples/TsToList.c

/*
 * Licensed Materials - Property of HCL
 *
 * IBM Informix  DataBlade Module
 * (C) Copyright International Business Machines Corporation 2002.
 * (c) Copyright HCL Technologies Ltd. 2017.  All Rights Reserved.
 *
 * COPYRIGHT LICENSE: 
 * This information contains sample application programs in source language,
 * which illustrate programming techniques on various operating platforms.
 * You may copy, modify, and distribute these sample programs in any form
 * without payment to IBM, for the purposes of developing, using, marketing 
 * or distributing application programs conforming to the application 
 * programming interface for the operating platform for which the sample 
 * programs are written. These examples have not been thoroughly tested under 
 * all conditions. IBM, therefore, cannot guarantee or imply reliability, 
 * serviceability, or function of these programs. You may copy, modify, and 
 * distribute these sample programs in any form without payment to IBM for 
 * the purposes of developing, using, marketing, or distributing application 
 * programs conforming to IBM's application programming interfaces. 
 * Each copy or any portion of these sample programs or any derivative work, 
 * must include a copyright notice as follows: 
 * © (your company name) (year). Portions of this code are derived from 
 * IBM Corp. Sample Programs. © Copyright IBM Corp. (enter the year or 
 * years). All rights reserved. 
 *
 */

/* 
 * SETUP:
 * 
 * create function TsToList(TimeSeries, integer) returns list
 * external name '/foo/bar/TsToList.so(ts_to_list)'
 * language c not variant;
 * 
 */


#include <stdio.h>
#include <mi.h>
#include <tseries.h>

/*
 * This function converts the first column of a timeseries
 * to an array.  This assumes the type is mi_real
 */

#include <math.h>

#ifdef NT
__declspec(dllexport) 
#endif
MI_COLLECTION *
ts_to_list(ts_timeseries *tsPtr, mi_integer col, MI_FPARAM *fParam)
{
    ts_tsdesc		*descPtr;
    ts_tselem		tselem;
    ts_tscan		*scan;
    MI_CONNECTION       *conn;
    int			scancode;
    MI_COLLECTION	*colPtr = NULL;
    MI_COLL_DESC        *colDesc = NULL;
    ts_typeinfo		*typePtr;
    mi_boolean		isNull;
    void   		*rslt;
    MI_TYPE_DESC   	*list_td;
    MI_TYPE_DESC   	*subtype_td;
    MI_TYPEID      	*subtype_id;
    char		 errbuf[100];
    

    /* get a connection for libmi */
    conn = mi_open(NULL,NULL,NULL);

    /* open a descriptor for the timeseries */
    descPtr = ts_open(conn, tsPtr, mi_fp_argtype(fParam, 0), 0);
    scan = ts_begin_scan(descPtr, 0, NULL, NULL);

    while ((scancode = ts_next(scan, &tselem)) != TS_SCAN_EOS) {
	switch(scancode) {
	  case TS_SCAN_ELEM:
	    if (colPtr == (MI_COLLECTION *)NULL) {
		/* first time */
		typePtr = ts_colinfo_number(descPtr, col);

		/* make sure type of column agrees with return type */
		list_td = mi_type_typedesc(conn, mi_fp_rettype(fParam, 0));
		subtype_td = mi_type_element_typedesc(list_td);
		subtype_id = mi_typedesc_typeid(subtype_td);
		if (!mi_typeid_equals(subtype_id, typePtr->ti_typeid)) {
		    subtype_td = mi_type_typedesc(conn, typePtr->ti_typeid);
		    sprintf(errbuf, "Subtype of %s must match column type (%s)",
						mi_type_typename(list_td),
						mi_type_typename(subtype_td));
		    mi_db_error_raise(NULL, MI_FATAL, errbuf, 0);
		}

		colPtr = mi_collection_create(conn, mi_fp_rettype(fParam, 0));
		colDesc = mi_collection_open(conn, colPtr);
	    }
	    
	    /* insert this ts_elem into the collection */
	    rslt = ts_get_col_by_number(descPtr,
					tselem,
					col,
					&isNull,
					ts_current_offset(scan));

	    if (!isNull) {
		/* we inseret only if it is not NULL. */
		mi_collection_insert(conn, colDesc, 
				     (MI_DATUM) rslt, MI_CURSOR_NEXT,0);
	    }
	    break;

	  case TS_SCAN_NULL:
	    break;
	}
    }

    ts_end_scan(scan);
    ts_close(descPtr);
    mi_collection_close(conn, colDesc);
    return(colPtr);
}