postgresql/contrib/intarray/_int_gin.c

#include "_int.h"

PG_FUNCTION_INFO_V1(ginint4_queryextract);
Datum ginint4_queryextract(PG_FUNCTION_ARGS);

Datum
ginint4_queryextract(PG_FUNCTION_ARGS) {
	uint32  *nentries = (uint32*)PG_GETARG_POINTER(1);
	StrategyNumber  strategy = PG_GETARG_UINT16(2);
	Datum	*res = NULL;
	
	*nentries = 0;

	if ( strategy == BooleanSearchStrategy ) {
		QUERYTYPE   *query = (QUERYTYPE*)PG_DETOAST_DATUM_COPY(PG_GETARG_POINTER(0));
		ITEM		*items = GETQUERY(query);
		int i;

		if (query->size == 0)
			PG_RETURN_POINTER(NULL);

		if ( shorterquery(items, query->size) == 0 )
			elog(ERROR,"Query requires full scan, GIN doesn't support it");

		pfree( query );

		query = (QUERYTYPE*)PG_DETOAST_DATUM(PG_GETARG_POINTER(0));
		items = GETQUERY(query);

		res = (Datum*)palloc(sizeof(Datum) * query->size);
		*nentries = 0;

		for(i=0;i<query->size;i++)
			if ( items[i].type == VAL ) { 
				res[*nentries] = Int32GetDatum( items[i].val );
				(*nentries)++;
			}
	} else {
		ArrayType   *query = PG_GETARG_ARRAYTYPE_P(0);
		int4 *arr;
		uint32 i;

		CHECKARRVALID(query);
		*nentries=ARRNELEMS(query);
		if ( *nentries > 0 ) {
			res = (Datum*)palloc(sizeof(Datum) * (*nentries));

			arr=ARRPTR(query);
			for(i=0;i<*nentries;i++) 
				res[i] = Int32GetDatum( arr[i] );
		}
	}

	PG_RETURN_POINTER( res );
}

PG_FUNCTION_INFO_V1(ginint4_consistent);
Datum ginint4_consistent(PG_FUNCTION_ARGS);

Datum
ginint4_consistent(PG_FUNCTION_ARGS) {
    bool    *check = (bool*)PG_GETARG_POINTER(0);
    StrategyNumber  strategy = PG_GETARG_UINT16(1);
    int res=FALSE;

    /* we can do not check array carefully, it's done by previous ginarrayextract call */

    switch( strategy ) {
        case RTOverlapStrategyNumber:
        case RTContainedByStrategyNumber:
            /* at least one element in check[] is true, so result = true */

            res = TRUE;
            break;
        case RTSameStrategyNumber:
        case RTContainsStrategyNumber:
            res = TRUE;
			do {
    			ArrayType   *query = PG_GETARG_ARRAYTYPE_P(2);
				int i, nentries=ARRNELEMS(query);

            	for(i=0;i<nentries;i++)
            	    if ( !check[i] ) {
            	        res = FALSE;
            	        break;
            	    }
			} while(0);
            break;
		 case BooleanSearchStrategy:
			do {
				QUERYTYPE	*query = (QUERYTYPE*)PG_DETOAST_DATUM(PG_GETARG_POINTER(2));
				res = ginconsistent( query, check ); 
			} while(0);
			break;
        default:
            elog(ERROR, "ginint4_consistent: unknown strategy number: %d", strategy);
    }

    PG_RETURN_BOOL(res);
}