regress.c

/*
 * $PostgreSQL: pgsql/src/test/regress/regress.c,v 1.72 2009/01/07 13:44:37 tgl Exp $
 */

#include "postgres.h"
#include "funcapi.h"
#include "tablefuncapi.h"

#include <float.h>
#include <math.h>

#include "access/transam.h"
#include "access/xact.h"
#include "catalog/pg_language.h"
#include "catalog/pg_type.h"
#include "cdb/memquota.h"
#include "commands/sequence.h"
#include "commands/trigger.h"
#include "executor/executor.h"
#include "executor/spi.h"
#include "port/atomics.h"
#include "parser/parse_expr.h"
#include "libpq/auth.h"
#include "libpq/hba.h"
#include "utils/builtins.h"
#include "utils/geo_decls.h"
#include "utils/lsyscache.h"
#include "utils/resscheduler.h"

#define P_MAXDIG 12
#define LDELIM			'('
#define RDELIM			')'
#define DELIM			','

extern Datum regress_dist_ptpath(PG_FUNCTION_ARGS);
extern Datum regress_path_dist(PG_FUNCTION_ARGS);
extern PATH *poly2path(POLYGON *poly);
extern Datum interpt_pp(PG_FUNCTION_ARGS);
extern void regress_lseg_construct(LSEG *lseg, Point *pt1, Point *pt2);
extern Datum overpaid(PG_FUNCTION_ARGS);
extern Datum boxarea(PG_FUNCTION_ARGS);
extern char *reverse_name(char *string);
extern int	oldstyle_length(int n, text *t);
extern Datum int44in(PG_FUNCTION_ARGS);
extern Datum int44out(PG_FUNCTION_ARGS);
extern Datum gp_str2bytea(PG_FUNCTION_ARGS);
extern Datum check_auth_time_constraints(PG_FUNCTION_ARGS);

/* table_functions test */
extern Datum multiset_example(PG_FUNCTION_ARGS);
extern Datum multiset_scalar_null(PG_FUNCTION_ARGS);
extern Datum multiset_scalar_value(PG_FUNCTION_ARGS);
extern Datum multiset_scalar_tuple(PG_FUNCTION_ARGS);
extern Datum multiset_setof_null(PG_FUNCTION_ARGS);
extern Datum multiset_setof_value(PG_FUNCTION_ARGS);
extern Datum multiset_materialize_good(PG_FUNCTION_ARGS);
extern Datum multiset_materialize_bad(PG_FUNCTION_ARGS);

/* table functions + dynamic type support */
extern Datum sessionize(PG_FUNCTION_ARGS);
extern Datum describe(PG_FUNCTION_ARGS);
extern Datum project(PG_FUNCTION_ARGS);
extern Datum project_describe(PG_FUNCTION_ARGS);

extern Datum userdata_describe(PG_FUNCTION_ARGS);
extern Datum userdata_project(PG_FUNCTION_ARGS);
extern Datum noop_project(PG_FUNCTION_ARGS);

/* resource queue support */
extern Datum checkResourceQueueMemoryLimits(PG_FUNCTION_ARGS);

extern Datum checkRelationAfterInvalidation(PG_FUNCTION_ARGS);

/*
 * test_atomic_ops was backported from 9.5. This prototype doesn't appear
 * in the upstream version, because the PG_FUNCTION_INFO_V1() macro includes
 * it since 9.4.
 */
extern Datum test_atomic_ops(PG_FUNCTION_ARGS);

#ifdef PG_MODULE_MAGIC
PG_MODULE_MAGIC;
#endif


/*
 * Distance from a point to a path
 */
PG_FUNCTION_INFO_V1(regress_dist_ptpath);

Datum
regress_dist_ptpath(PG_FUNCTION_ARGS)
{
	Point	   *pt = PG_GETARG_POINT_P(0);
	PATH	   *path = PG_GETARG_PATH_P(1);
	float8		result = 0.0;	/* keep compiler quiet */
	float8		tmp;
	int			i;
	LSEG		lseg;

	switch (path->npts)
	{
		case 0:
			PG_RETURN_NULL();
		case 1:
			result = point_dt(pt, &path->p[0]);
			break;
		default:

			/*
			 * the distance from a point to a path is the smallest distance
			 * from the point to any of its constituent segments.
			 */
			Assert(path->npts > 1);
			for (i = 0; i < path->npts - 1; ++i)
			{
				regress_lseg_construct(&lseg, &path->p[i], &path->p[i + 1]);
				tmp = DatumGetFloat8(DirectFunctionCall2(dist_ps,
														 PointPGetDatum(pt),
													  LsegPGetDatum(&lseg)));
				if (i == 0 || tmp < result)
					result = tmp;
			}
			break;
	}
	PG_RETURN_FLOAT8(result);
}

/*
 * this essentially does a cartesian product of the lsegs in the
 * two paths, and finds the min distance between any two lsegs
 */
PG_FUNCTION_INFO_V1(regress_path_dist);

Datum
regress_path_dist(PG_FUNCTION_ARGS)
{
	PATH	   *p1 = PG_GETARG_PATH_P(0);
	PATH	   *p2 = PG_GETARG_PATH_P(1);
	bool		have_min = false;
	float8		min = 0.0;		/* initialize to keep compiler quiet */
	float8		tmp;
	int			i,
				j;
	LSEG		seg1,
				seg2;

	for (i = 0; i < p1->npts - 1; i++)
	{
		for (j = 0; j < p2->npts - 1; j++)
		{
			regress_lseg_construct(&seg1, &p1->p[i], &p1->p[i + 1]);
			regress_lseg_construct(&seg2, &p2->p[j], &p2->p[j + 1]);

			tmp = DatumGetFloat8(DirectFunctionCall2(lseg_distance,
													 LsegPGetDatum(&seg1),
													 LsegPGetDatum(&seg2)));
			if (!have_min || tmp < min)
			{
				min = tmp;
				have_min = true;
			}
		}
	}

	if (!have_min)
		PG_RETURN_NULL();

	PG_RETURN_FLOAT8(min);
}

PATH *
poly2path(POLYGON *poly)
{
	int			i;
	char	   *output = (char *) palloc(2 * (P_MAXDIG + 1) * poly->npts + 64);
	char		buf[2 * (P_MAXDIG) + 20];

	sprintf(output, "(1, %*d", P_MAXDIG, poly->npts);

	for (i = 0; i < poly->npts; i++)
	{
		snprintf(buf, sizeof(buf), ",%*g,%*g",
				 P_MAXDIG, poly->p[i].x, P_MAXDIG, poly->p[i].y);
		strcat(output, buf);
	}

	snprintf(buf, sizeof(buf), "%c", RDELIM);
	strcat(output, buf);
	return DatumGetPathP(DirectFunctionCall1(path_in,
											 CStringGetDatum(output)));
}

/* return the point where two paths intersect, or NULL if no intersection. */
PG_FUNCTION_INFO_V1(interpt_pp);

Datum
interpt_pp(PG_FUNCTION_ARGS)
{
	PATH	   *p1 = PG_GETARG_PATH_P(0);
	PATH	   *p2 = PG_GETARG_PATH_P(1);
	int			i,
				j;
	LSEG		seg1,
				seg2;
	bool		found;			/* We've found the intersection */

	found = false;				/* Haven't found it yet */

	for (i = 0; i < p1->npts - 1 && !found; i++)
	{
		regress_lseg_construct(&seg1, &p1->p[i], &p1->p[i + 1]);
		for (j = 0; j < p2->npts - 1 && !found; j++)
		{
			regress_lseg_construct(&seg2, &p2->p[j], &p2->p[j + 1]);
			if (DatumGetBool(DirectFunctionCall2(lseg_intersect,
												 LsegPGetDatum(&seg1),
												 LsegPGetDatum(&seg2))))
				found = true;
		}
	}

	if (!found)
		PG_RETURN_NULL();

	/*
	 * Note: DirectFunctionCall2 will kick out an error if lseg_interpt()
	 * returns NULL, but that should be impossible since we know the two
	 * segments intersect.
	 */
	PG_RETURN_DATUM(DirectFunctionCall2(lseg_interpt,
										LsegPGetDatum(&seg1),
										LsegPGetDatum(&seg2)));
}


/* like lseg_construct, but assume space already allocated */
void
regress_lseg_construct(LSEG *lseg, Point *pt1, Point *pt2)
{
	lseg->p[0].x = pt1->x;
	lseg->p[0].y = pt1->y;
	lseg->p[1].x = pt2->x;
	lseg->p[1].y = pt2->y;
	lseg->m = point_sl(pt1, pt2);
}

PG_FUNCTION_INFO_V1(overpaid);

Datum
overpaid(PG_FUNCTION_ARGS)
{
	HeapTupleHeader tuple = PG_GETARG_HEAPTUPLEHEADER(0);
	bool		isnull;
	int32		salary;

	salary = DatumGetInt32(GetAttributeByName(tuple, "salary", &isnull));
	if (isnull)
		PG_RETURN_NULL();
	PG_RETURN_BOOL(salary > 699);
}

/* New type "widget"
 * This used to be "circle", but I added circle to builtins,
 *	so needed to make sure the names do not collide. - tgl 97/04/21
 */

typedef struct
{
	Point		center;
	double		radius;
}	WIDGET;

WIDGET	   *widget_in(char *str);
char	   *widget_out(WIDGET * widget);
extern Datum pt_in_widget(PG_FUNCTION_ARGS);

#define NARGS	3

WIDGET *
widget_in(char *str)
{
	char	   *p,
			   *coord[NARGS],
				buf2[1000];
	int			i;
	WIDGET	   *result;

	if (str == NULL)
		return NULL;
	for (i = 0, p = str; *p && i < NARGS && *p != RDELIM; p++)
		if (*p == ',' || (*p == LDELIM && !i))
			coord[i++] = p + 1;
	if (i < NARGS - 1)
		return NULL;
	result = (WIDGET *) palloc(sizeof(WIDGET));
	result->center.x = atof(coord[0]);
	result->center.y = atof(coord[1]);
	result->radius = atof(coord[2]);

	snprintf(buf2, sizeof(buf2), "widget_in: read (%f, %f, %f)\n",
			 result->center.x, result->center.y, result->radius);
	return result;
}

char *
widget_out(WIDGET * widget)
{
	char	   *result;

	if (widget == NULL)
		return NULL;

	result = (char *) palloc(60);
	sprintf(result, "(%g,%g,%g)",
			widget->center.x, widget->center.y, widget->radius);
	return result;
}

PG_FUNCTION_INFO_V1(pt_in_widget);

Datum
pt_in_widget(PG_FUNCTION_ARGS)
{
	Point	   *point = PG_GETARG_POINT_P(0);
	WIDGET	   *widget = (WIDGET *) PG_GETARG_POINTER(1);

	PG_RETURN_BOOL(point_dt(point, &widget->center) < widget->radius);
}

PG_FUNCTION_INFO_V1(boxarea);

Datum
boxarea(PG_FUNCTION_ARGS)
{
	BOX		   *box = PG_GETARG_BOX_P(0);
	double		width,
				height;

	width = Abs(box->high.x - box->low.x);
	height = Abs(box->high.y - box->low.y);
	PG_RETURN_FLOAT8(width * height);
}

char *
reverse_name(char *string)
{
	int			i;
	int			len;
	char	   *new_string;

	new_string = palloc0(NAMEDATALEN);
	for (i = 0; i < NAMEDATALEN && string[i]; ++i)
		;
	if (i == NAMEDATALEN || !string[i])
		--i;
	len = i;
	for (; i >= 0; --i)
		new_string[len - i] = string[i];
	return new_string;
}

/*
 * This rather silly function is just to test that oldstyle functions
 * work correctly on toast-able inputs.
 */
int
oldstyle_length(int n, text *t)
{
	int			len = 0;

	if (t)
		len = VARSIZE(t) - VARHDRSZ;

	return n + len;
}


static TransactionId fd17b_xid = InvalidTransactionId;
static TransactionId fd17a_xid = InvalidTransactionId;
static int	fd17b_level = 0;
static int	fd17a_level = 0;
static bool fd17b_recursion = true;
static bool fd17a_recursion = true;
extern Datum funny_dup17(PG_FUNCTION_ARGS);

PG_FUNCTION_INFO_V1(funny_dup17);

Datum
funny_dup17(PG_FUNCTION_ARGS)
{
	TriggerData *trigdata = (TriggerData *) fcinfo->context;
	TransactionId *xid;
	int		   *level;
	bool	   *recursion;
	Relation	rel;
	TupleDesc	tupdesc;
	HeapTuple	tuple;
	char	   *query,
			   *fieldval,
			   *fieldtype;
	char	   *when;
	int			inserted;
	int			selected = 0;
	int			ret;

	if (!CALLED_AS_TRIGGER(fcinfo))
		elog(ERROR, "funny_dup17: not fired by trigger manager");

	tuple = trigdata->tg_trigtuple;
	rel = trigdata->tg_relation;
	tupdesc = rel->rd_att;
	if (TRIGGER_FIRED_BEFORE(trigdata->tg_event))
	{
		xid = &fd17b_xid;
		level = &fd17b_level;
		recursion = &fd17b_recursion;
		when = "BEFORE";
	}
	else
	{
		xid = &fd17a_xid;
		level = &fd17a_level;
		recursion = &fd17a_recursion;
		when = "AFTER ";
	}

	if (!TransactionIdIsCurrentTransactionId(*xid))
	{
		*xid = GetCurrentTransactionId();
		*level = 0;
		*recursion = true;
	}

	if (*level == 17)
	{
		*recursion = false;
		return PointerGetDatum(tuple);
	}

	if (!(*recursion))
		return PointerGetDatum(tuple);

	(*level)++;

	SPI_connect();

	fieldval = SPI_getvalue(tuple, tupdesc, 1);
	fieldtype = SPI_gettype(tupdesc, 1);

	query = (char *) palloc(100 + NAMEDATALEN * 3 +
							strlen(fieldval) + strlen(fieldtype));

	sprintf(query, "insert into %s select * from %s where %s = '%s'::%s",
			SPI_getrelname(rel), SPI_getrelname(rel),
			SPI_fname(tupdesc, 1),
			fieldval, fieldtype);

	if ((ret = SPI_exec(query, 0)) < 0)
		elog(ERROR, "funny_dup17 (fired %s) on level %3d: SPI_exec (insert ...) returned %d",
			 when, *level, ret);

	inserted = SPI_processed;

	sprintf(query, "select count (*) from %s where %s = '%s'::%s",
			SPI_getrelname(rel),
			SPI_fname(tupdesc, 1),
			fieldval, fieldtype);

	if ((ret = SPI_exec(query, 0)) < 0)
		elog(ERROR, "funny_dup17 (fired %s) on level %3d: SPI_exec (select ...) returned %d",
			 when, *level, ret);

	if (SPI_processed > 0)
	{
		selected = DatumGetInt32(DirectFunctionCall1(int4in,
												CStringGetDatum(SPI_getvalue(
													   SPI_tuptable->vals[0],
													   SPI_tuptable->tupdesc,
																			 1
																		))));
	}

	elog(DEBUG4, "funny_dup17 (fired %s) on level %3d: %d/%d tuples inserted/selected",
		 when, *level, inserted, selected);

	SPI_finish();

	(*level)--;

	if (*level == 0)
		*xid = InvalidTransactionId;

	return PointerGetDatum(tuple);
}

extern Datum ttdummy(PG_FUNCTION_ARGS);
extern Datum set_ttdummy(PG_FUNCTION_ARGS);

#define TTDUMMY_INFINITY	999999

static SPIPlanPtr splan = NULL;
static bool ttoff = false;

PG_FUNCTION_INFO_V1(ttdummy);

Datum
ttdummy(PG_FUNCTION_ARGS)
{
	TriggerData *trigdata = (TriggerData *) fcinfo->context;
	Trigger    *trigger;		/* to get trigger name */
	char	  **args;			/* arguments */
	int			attnum[2];		/* fnumbers of start/stop columns */
	Datum		oldon,
				oldoff;
	Datum		newon,
				newoff;
	Datum	   *cvals;			/* column values */
	char	   *cnulls;			/* column nulls */
	char	   *relname;		/* triggered relation name */
	Relation	rel;			/* triggered relation */
	HeapTuple	trigtuple;
	HeapTuple	newtuple = NULL;
	HeapTuple	rettuple;
	TupleDesc	tupdesc;		/* tuple description */
	int			natts;			/* # of attributes */
	bool		isnull;			/* to know is some column NULL or not */
	int			ret;
	int			i;

	if (!CALLED_AS_TRIGGER(fcinfo))
		elog(ERROR, "ttdummy: not fired by trigger manager");
	if (TRIGGER_FIRED_FOR_STATEMENT(trigdata->tg_event))
		elog(ERROR, "ttdummy: cannot process STATEMENT events");
	if (TRIGGER_FIRED_AFTER(trigdata->tg_event))
		elog(ERROR, "ttdummy: must be fired before event");
	if (TRIGGER_FIRED_BY_INSERT(trigdata->tg_event))
		elog(ERROR, "ttdummy: cannot process INSERT event");
	if (TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
		newtuple = trigdata->tg_newtuple;

	trigtuple = trigdata->tg_trigtuple;

	rel = trigdata->tg_relation;
	relname = SPI_getrelname(rel);

	/* check if TT is OFF for this relation */
	if (ttoff)					/* OFF - nothing to do */
	{
		pfree(relname);
		return PointerGetDatum((newtuple != NULL) ? newtuple : trigtuple);
	}

	trigger = trigdata->tg_trigger;

	if (trigger->tgnargs != 2)
		elog(ERROR, "ttdummy (%s): invalid (!= 2) number of arguments %d",
			 relname, trigger->tgnargs);

	args = trigger->tgargs;
	tupdesc = rel->rd_att;
	natts = tupdesc->natts;

	for (i = 0; i < 2; i++)
	{
		attnum[i] = SPI_fnumber(tupdesc, args[i]);
		if (attnum[i] < 0)
			elog(ERROR, "ttdummy (%s): there is no attribute %s", relname, args[i]);
		if (SPI_gettypeid(tupdesc, attnum[i]) != INT4OID)
			elog(ERROR, "ttdummy (%s): attributes %s and %s must be of abstime type",
				 relname, args[0], args[1]);
	}

	oldon = SPI_getbinval(trigtuple, tupdesc, attnum[0], &isnull);
	if (isnull)
		elog(ERROR, "ttdummy (%s): %s must be NOT NULL", relname, args[0]);

	oldoff = SPI_getbinval(trigtuple, tupdesc, attnum[1], &isnull);
	if (isnull)
		elog(ERROR, "ttdummy (%s): %s must be NOT NULL", relname, args[1]);

	if (newtuple != NULL)		/* UPDATE */
	{
		newon = SPI_getbinval(newtuple, tupdesc, attnum[0], &isnull);
		if (isnull)
			elog(ERROR, "ttdummy (%s): %s must be NOT NULL", relname, args[0]);
		newoff = SPI_getbinval(newtuple, tupdesc, attnum[1], &isnull);
		if (isnull)
			elog(ERROR, "ttdummy (%s): %s must be NOT NULL", relname, args[1]);

		if (oldon != newon || oldoff != newoff)
			elog(ERROR, "ttdummy (%s): you cannot change %s and/or %s columns (use set_ttdummy)",
				 relname, args[0], args[1]);

		if (newoff != TTDUMMY_INFINITY)
		{
			pfree(relname);		/* allocated in upper executor context */
			return PointerGetDatum(NULL);
		}
	}
	else if (oldoff != TTDUMMY_INFINITY)		/* DELETE */
	{
		pfree(relname);
		return PointerGetDatum(NULL);
	}

	newoff = DirectFunctionCall1(nextval, CStringGetTextDatum("ttdummy_seq"));
		/* nextval now returns int64; coerce down to int32 */
		newoff = Int32GetDatum((int32) DatumGetInt64(newoff));

	/* Connect to SPI manager */
	if ((ret = SPI_connect()) < 0)
		elog(ERROR, "ttdummy (%s): SPI_connect returned %d", relname, ret);

	/* Fetch tuple values and nulls */
	cvals = (Datum *) palloc(natts * sizeof(Datum));
	cnulls = (char *) palloc(natts * sizeof(char));
	for (i = 0; i < natts; i++)
	{
		cvals[i] = SPI_getbinval((newtuple != NULL) ? newtuple : trigtuple,
								 tupdesc, i + 1, &isnull);
		cnulls[i] = (isnull) ? 'n' : ' ';
	}

	/* change date column(s) */
	if (newtuple)				/* UPDATE */
	{
		cvals[attnum[0] - 1] = newoff;	/* start_date eq current date */
		cnulls[attnum[0] - 1] = ' ';
		cvals[attnum[1] - 1] = TTDUMMY_INFINITY;		/* stop_date eq INFINITY */
		cnulls[attnum[1] - 1] = ' ';
	}
	else
		/* DELETE */
	{
		cvals[attnum[1] - 1] = newoff;	/* stop_date eq current date */
		cnulls[attnum[1] - 1] = ' ';
	}

	/* if there is no plan ... */
	if (splan == NULL)
	{
		SPIPlanPtr	pplan;
		Oid		   *ctypes;
		char	   *query;

		/* allocate space in preparation */
		ctypes = (Oid *) palloc(natts * sizeof(Oid));
		query = (char *) palloc(100 + 16 * natts);

		/*
		 * Construct query: INSERT INTO _relation_ VALUES ($1, ...)
		 */
		sprintf(query, "INSERT INTO %s VALUES (", relname);
		for (i = 1; i <= natts; i++)
		{
			sprintf(query + strlen(query), "$%d%s",
					i, (i < natts) ? ", " : ")");
			ctypes[i - 1] = SPI_gettypeid(tupdesc, i);
		}

		/* Prepare plan for query */
		pplan = SPI_prepare(query, natts, ctypes);
		if (pplan == NULL)
			elog(ERROR, "ttdummy (%s): SPI_prepare returned %d", relname, SPI_result);

		pplan = SPI_saveplan(pplan);
		if (pplan == NULL)
			elog(ERROR, "ttdummy (%s): SPI_saveplan returned %d", relname, SPI_result);

		splan = pplan;
	}

	ret = SPI_execp(splan, cvals, cnulls, 0);

	if (ret < 0)
		elog(ERROR, "ttdummy (%s): SPI_execp returned %d", relname, ret);

	/* Tuple to return to upper Executor ... */
	if (newtuple)				/* UPDATE */
	{
		HeapTuple	tmptuple;

		tmptuple = SPI_copytuple(trigtuple);
		rettuple = SPI_modifytuple(rel, tmptuple, 1, &(attnum[1]), &newoff, NULL);
		SPI_freetuple(tmptuple);
	}
	else
		/* DELETE */
		rettuple = trigtuple;

	SPI_finish();				/* don't forget say Bye to SPI mgr */

	pfree(relname);

	return PointerGetDatum(rettuple);
}

PG_FUNCTION_INFO_V1(set_ttdummy);

Datum
set_ttdummy(PG_FUNCTION_ARGS)
{
	int32		on = PG_GETARG_INT32(0);

	if (ttoff)					/* OFF currently */
	{
		if (on == 0)
			PG_RETURN_INT32(0);

		/* turn ON */
		ttoff = false;
		PG_RETURN_INT32(0);
	}

	/* ON currently */
	if (on != 0)
		PG_RETURN_INT32(1);

	/* turn OFF */
	ttoff = true;

	PG_RETURN_INT32(1);
}


/*
 * Type int44 has no real-world use, but the regression tests use it.
 * It's a four-element vector of int4's.
 */

/*
 *		int44in			- converts "num num ..." to internal form
 *
 *		Note: Fills any missing positions with zeroes.
 */
PG_FUNCTION_INFO_V1(int44in);

Datum
int44in(PG_FUNCTION_ARGS)
{
	char	   *input_string = PG_GETARG_CSTRING(0);
	int32	   *result = (int32 *) palloc(4 * sizeof(int32));
	int			i;

	i = sscanf(input_string,
			   "%d, %d, %d, %d",
			   &result[0],
			   &result[1],
			   &result[2],
			   &result[3]);
	while (i < 4)
		result[i++] = 0;

	PG_RETURN_POINTER(result);
}

/*
 *		int44out		- converts internal form to "num num ..."
 */
PG_FUNCTION_INFO_V1(int44out);

Datum
int44out(PG_FUNCTION_ARGS)
{
	int32	   *an_array = (int32 *) PG_GETARG_POINTER(0);
	char	   *result = (char *) palloc(16 * 4);		/* Allow 14 digits +
														 * sign */
	int			i;
	char	   *walk;

	walk = result;
	for (i = 0; i < 4; i++)
	{
		pg_ltoa(an_array[i], walk);
		while (*++walk != '\0')
			;
		*walk++ = ' ';
	}
	*--walk = '\0';
	PG_RETURN_CSTRING(result);
}


extern Datum check_primary_key(PG_FUNCTION_ARGS);
extern Datum check_foreign_key(PG_FUNCTION_ARGS);


typedef struct
{
	char	   *ident;
	int			nplans;
	void	  **splan;
}	EPlan;

static EPlan *FPlans = NULL;
static int	nFPlans = 0;
static EPlan *PPlans = NULL;
static int	nPPlans = 0;

static EPlan *find_plan(char *ident, EPlan ** eplan, int *nplans);

/*
 * check_primary_key () -- check that key in tuple being inserted/updated
 *			 references existing tuple in "primary" table.
 * Though it's called without args You have to specify referenced
 * table/keys while creating trigger:  key field names in triggered table,
 * referenced table name, referenced key field names:
 * EXECUTE PROCEDURE
 * check_primary_key ('Fkey1', 'Fkey2', 'Ptable', 'Pkey1', 'Pkey2').
 */

PG_FUNCTION_INFO_V1(check_primary_key);

Datum
check_primary_key(PG_FUNCTION_ARGS)
{
	TriggerData *trigdata = (TriggerData *) fcinfo->context;
	Trigger    *trigger;		/* to get trigger name */
	int			nargs;			/* # of args specified in CREATE TRIGGER */
	char	  **args;			/* arguments: column names and table name */
	int			nkeys;			/* # of key columns (= nargs / 2) */
	Datum	   *kvals;			/* key values */
	char	   *relname;		/* referenced relation name */
	Relation	rel;			/* triggered relation */
	HeapTuple	tuple = NULL;	/* tuple to return */
	TupleDesc	tupdesc;		/* tuple description */
	EPlan	   *plan;			/* prepared plan */
	Oid		   *argtypes = NULL;	/* key types to prepare execution plan */
	bool		isnull;			/* to know is some column NULL or not */
	char		ident[2 * NAMEDATALEN]; /* to identify myself */
	int			ret;
	int			i;

#ifdef	DEBUG_QUERY
	elog(DEBUG4, "check_primary_key: Enter Function");
#endif

	/*
	 * Some checks first...
	 */

	/* Called by trigger manager ? */
	if (!CALLED_AS_TRIGGER(fcinfo))
		/* internal error */
		elog(ERROR, "check_primary_key: not fired by trigger manager");

	/* Should be called for ROW trigger */
	if (TRIGGER_FIRED_FOR_STATEMENT(trigdata->tg_event))
		/* internal error */
		elog(ERROR, "check_primary_key: can't process STATEMENT events");

	/* If INSERTion then must check Tuple to being inserted */
	if (TRIGGER_FIRED_BY_INSERT(trigdata->tg_event))
		tuple = trigdata->tg_trigtuple;

	/* Not should be called for DELETE */
	else if (TRIGGER_FIRED_BY_DELETE(trigdata->tg_event))
		/* internal error */
		elog(ERROR, "check_primary_key: can't process DELETE events");

	/* If UPDATion the must check new Tuple, not old one */
	else
		tuple = trigdata->tg_newtuple;

	trigger = trigdata->tg_trigger;
	nargs = trigger->tgnargs;
	args = trigger->tgargs;

	if (nargs % 2 != 1)			/* odd number of arguments! */
		/* internal error */
		elog(ERROR, "check_primary_key: odd number of arguments should be specified");

	nkeys = nargs / 2;
	relname = args[nkeys];
	rel = trigdata->tg_relation;
	tupdesc = rel->rd_att;

	/* Connect to SPI manager */
	if ((ret = SPI_connect()) < 0)
		/* internal error */
		elog(ERROR, "check_primary_key: SPI_connect returned %d", ret);

	/*
	 * We use SPI plan preparation feature, so allocate space to place key
	 * values.
	 */
	kvals = (Datum *) palloc(nkeys * sizeof(Datum));

	/*
	 * Construct ident string as TriggerName $ TriggeredRelationId and try to
	 * find prepared execution plan.
	 */
	snprintf(ident, sizeof(ident), "%s$%u", trigger->tgname, rel->rd_id);
	plan = find_plan(ident, &PPlans, &nPPlans);

	/* if there is no plan then allocate argtypes for preparation */
	if (plan->nplans <= 0)
		argtypes = (Oid *) palloc(nkeys * sizeof(Oid));

	/* For each column in key ... */
	for (i = 0; i < nkeys; i++)
	{
		/* get index of column in tuple */
		int			fnumber = SPI_fnumber(tupdesc, args[i]);

		/* Bad guys may give us un-existing column in CREATE TRIGGER */
		if (fnumber < 0)
			ereport(ERROR,
					(errcode(ERRCODE_UNDEFINED_COLUMN),
					 errmsg("there is no attribute \"%s\" in relation \"%s\"",
							args[i], SPI_getrelname(rel))));

		/* Well, get binary (in internal format) value of column */
		kvals[i] = SPI_getbinval(tuple, tupdesc, fnumber, &isnull);

		/*
		 * If it's NULL then nothing to do! DON'T FORGET call SPI_finish ()!
		 * DON'T FORGET return tuple! Executor inserts tuple you're returning!
		 * If you return NULL then nothing will be inserted!
		 */
		if (isnull)
		{
			SPI_finish();
			return PointerGetDatum(tuple);
		}

		if (plan->nplans <= 0)	/* Get typeId of column */
			argtypes[i] = SPI_gettypeid(tupdesc, fnumber);
	}

	/*
	 * If we have to prepare plan ...
	 */
	if (plan->nplans <= 0)
	{
		void	   *pplan;
		char		sql[8192];

		/*
		 * Construct query: SELECT 1 FROM _referenced_relation_ WHERE Pkey1 =
		 * $1 [AND Pkey2 = $2 [...]]
		 */
		snprintf(sql, sizeof(sql), "select 1 from %s where ", relname);
		for (i = 0; i < nkeys; i++)
		{
			snprintf(sql + strlen(sql), sizeof(sql) - strlen(sql), "%s = $%d %s",
				  args[i + nkeys + 1], i + 1, (i < nkeys - 1) ? "and " : "");
		}

		/* Prepare plan for query */
		pplan = SPI_prepare(sql, nkeys, argtypes);
		if (pplan == NULL)
			/* internal error */
			elog(ERROR, "check_primary_key: SPI_prepare returned %d", SPI_result);

		/*
		 * Remember that SPI_prepare places plan in current memory context -
		 * so, we have to save plan in Top memory context for latter use.
		 */
		pplan = SPI_saveplan(pplan);
		if (pplan == NULL)
			/* internal error */
			elog(ERROR, "check_primary_key: SPI_saveplan returned %d", SPI_result);
		plan->splan = (void **) malloc(sizeof(void *));
		*(plan->splan) = pplan;
		plan->nplans = 1;
	}

	/*
	 * Ok, execute prepared plan.
	 */
	ret = SPI_execp(*(plan->splan), kvals, NULL, 1);
	/* we have no NULLs - so we pass   ^^^^   here */

	if (ret < 0)
		/* internal error */
		elog(ERROR, "check_primary_key: SPI_execp returned %d", ret);

	/*
	 * If there are no tuples returned by SELECT then ...
	 */
	if (SPI_processed == 0)
		ereport(ERROR,
				(errcode(ERRCODE_TRIGGERED_ACTION_EXCEPTION),
				 errmsg("tuple references non-existent key"),
				 errdetail("Trigger \"%s\" found tuple referencing non-existent key in \"%s\".", trigger->tgname, relname)));

	SPI_finish();

	return PointerGetDatum(tuple);
}

/*
 * check_foreign_key () -- check that key in tuple being deleted/updated
 *			 is not referenced by tuples in "foreign" table(s).
 * Though it's called without args You have to specify (while creating trigger):
 * number of references, action to do if key referenced
 * ('restrict' | 'setnull' | 'cascade'), key field names in triggered
 * ("primary") table and referencing table(s)/keys:
 * EXECUTE PROCEDURE
 * check_foreign_key (2, 'restrict', 'Pkey1', 'Pkey2',
 * 'Ftable1', 'Fkey11', 'Fkey12', 'Ftable2', 'Fkey21', 'Fkey22').
 */

PG_FUNCTION_INFO_V1(check_foreign_key);

Datum
check_foreign_key(PG_FUNCTION_ARGS)
{
	TriggerData *trigdata = (TriggerData *) fcinfo->context;
	Trigger    *trigger;		/* to get trigger name */
	int			nargs;			/* # of args specified in CREATE TRIGGER */
	char	  **args;			/* arguments: as described above */
	char	  **args_temp;
	int			nrefs;			/* number of references (== # of plans) */
	char		action;			/* 'R'estrict | 'S'etnull | 'C'ascade */
	int			nkeys;			/* # of key columns */
	Datum	   *kvals;			/* key values */
	char	   *relname;		/* referencing relation name */
	Relation	rel;			/* triggered relation */
	HeapTuple	trigtuple = NULL;		/* tuple to being changed */
	HeapTuple	newtuple = NULL;	/* tuple to return */
	TupleDesc	tupdesc;		/* tuple description */
	EPlan	   *plan;			/* prepared plan(s) */
	Oid		   *argtypes = NULL;	/* key types to prepare execution plan */
	bool		isnull;			/* to know is some column NULL or not */
	bool		isequal = true; /* are keys in both tuples equal (in UPDATE) */
	char		ident[2 * NAMEDATALEN]; /* to identify myself */
	int			is_update = 0;
	int			ret;
	int			i,
				r;

#ifdef DEBUG_QUERY
	elog(DEBUG4, "check_foreign_key: Enter Function");
#endif

	/*
	 * Some checks first...
	 */

	/* Called by trigger manager ? */
	if (!CALLED_AS_TRIGGER(fcinfo))
		/* internal error */
		elog(ERROR, "check_foreign_key: not fired by trigger manager");

	/* Should be called for ROW trigger */
	if (TRIGGER_FIRED_FOR_STATEMENT(trigdata->tg_event))
		/* internal error */
		elog(ERROR, "check_foreign_key: can't process STATEMENT events");

	/* Not should be called for INSERT */
	if (TRIGGER_FIRED_BY_INSERT(trigdata->tg_event))
		/* internal error */
		elog(ERROR, "check_foreign_key: can't process INSERT events");

	/* Have to check tg_trigtuple - tuple being deleted */
	trigtuple = trigdata->tg_trigtuple;

	/*
	 * But if this is UPDATE then we have to return tg_newtuple. Also, if key
	 * in tg_newtuple is the same as in tg_trigtuple then nothing to do.
	 */
	is_update = 0;
	if (TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
	{
		newtuple = trigdata->tg_newtuple;
		is_update = 1;
	}
	trigger = trigdata->tg_trigger;
	nargs = trigger->tgnargs;
	args = trigger->tgargs;

	if (nargs < 5)				/* nrefs, action, key, Relation, key - at
								 * least */
		/* internal error */
		elog(ERROR, "check_foreign_key: too short %d (< 5) list of arguments", nargs);

	nrefs = pg_atoi(args[0], sizeof(int), 0);
	if (nrefs < 1)
		/* internal error */
		elog(ERROR, "check_foreign_key: %d (< 1) number of references specified", nrefs);
	action = tolower((unsigned char) *(args[1]));
	if (action != 'r' && action != 'c' && action != 's')
		/* internal error */
		elog(ERROR, "check_foreign_key: invalid action %s", args[1]);
	nargs -= 2;
	args += 2;
	nkeys = (nargs - nrefs) / (nrefs + 1);
	if (nkeys <= 0 || nargs != (nrefs + nkeys * (nrefs + 1)))
		/* internal error */
		elog(ERROR, "check_foreign_key: invalid number of arguments %d for %d references",
			 nargs + 2, nrefs);

	rel = trigdata->tg_relation;
	tupdesc = rel->rd_att;

	/* Connect to SPI manager */
	if ((ret = SPI_connect()) < 0)
		/* internal error */
		elog(ERROR, "check_foreign_key: SPI_connect returned %d", ret);

	/*
	 * We use SPI plan preparation feature, so allocate space to place key
	 * values.
	 */
	kvals = (Datum *) palloc(nkeys * sizeof(Datum));

	/*
	 * Construct ident string as TriggerName $ TriggeredRelationId and try to
	 * find prepared execution plan(s).
	 */
	snprintf(ident, sizeof(ident), "%s$%u", trigger->tgname, rel->rd_id);
	plan = find_plan(ident, &FPlans, &nFPlans);

	/* if there is no plan(s) then allocate argtypes for preparation */
	if (plan->nplans <= 0)
		argtypes = (Oid *) palloc(nkeys * sizeof(Oid));

	/*
	 * else - check that we have exactly nrefs plan(s) ready
	 */
	else if (plan->nplans != nrefs)
		/* internal error */
		elog(ERROR, "%s: check_foreign_key: # of plans changed in meantime",
			 trigger->tgname);

	/* For each column in key ... */
	for (i = 0; i < nkeys; i++)
	{
		/* get index of column in tuple */
		int			fnumber = SPI_fnumber(tupdesc, args[i]);

		/* Bad guys may give us un-existing column in CREATE TRIGGER */
		if (fnumber < 0)
			ereport(ERROR,
					(errcode(ERRCODE_UNDEFINED_COLUMN),
					 errmsg("there is no attribute \"%s\" in relation \"%s\"",
							args[i], SPI_getrelname(rel))));

		/* Well, get binary (in internal format) value of column */
		kvals[i] = SPI_getbinval(trigtuple, tupdesc, fnumber, &isnull);

		/*
		 * If it's NULL then nothing to do! DON'T FORGET call SPI_finish ()!
		 * DON'T FORGET return tuple! Executor inserts tuple you're returning!
		 * If you return NULL then nothing will be inserted!
		 */
		if (isnull)
		{
			SPI_finish();
			return PointerGetDatum((newtuple == NULL) ? trigtuple : newtuple);
		}

		/*
		 * If UPDATE then get column value from new tuple being inserted and
		 * compare is this the same as old one. For the moment we use string
		 * presentation of values...
		 */
		if (newtuple != NULL)
		{
			char	   *oldval = SPI_getvalue(trigtuple, tupdesc, fnumber);
			char	   *newval;

			/* this shouldn't happen! SPI_ERROR_NOOUTFUNC ? */
			if (oldval == NULL)
				/* internal error */
				elog(ERROR, "check_foreign_key: SPI_getvalue returned %d", SPI_result);
			newval = SPI_getvalue(newtuple, tupdesc, fnumber);
			if (newval == NULL || strcmp(oldval, newval) != 0)
				isequal = false;
		}

		if (plan->nplans <= 0)	/* Get typeId of column */
			argtypes[i] = SPI_gettypeid(tupdesc, fnumber);
	}
	args_temp = args;
	nargs -= nkeys;
	args += nkeys;

	/*
	 * If we have to prepare plans ...
	 */
	if (plan->nplans <= 0)
	{
		void	   *pplan;
		char		sql[8192];
		char	  **args2 = args;

		plan->splan = (void **) malloc(nrefs * sizeof(void *));

		for (r = 0; r < nrefs; r++)
		{
			relname = args2[0];

			/*---------
			 * For 'R'estrict action we construct SELECT query:
			 *
			 *	SELECT 1
			 *	FROM _referencing_relation_
			 *	WHERE Fkey1 = $1 [AND Fkey2 = $2 [...]]
			 *
			 *	to check is tuple referenced or not.
			 *---------
			 */
			if (action == 'r')

				snprintf(sql, sizeof(sql), "select 1 from %s where ", relname);

			/*---------
			 * For 'C'ascade action we construct DELETE query
			 *
			 *	DELETE
			 *	FROM _referencing_relation_
			 *	WHERE Fkey1 = $1 [AND Fkey2 = $2 [...]]
			 *
			 * to delete all referencing tuples.
			 *---------
			 */

			/*
			 * Max : Cascade with UPDATE query i create update query that
			 * updates new key values in referenced tables
			 */


			else if (action == 'c')
			{
				if (is_update == 1)
				{
					int			fn;
					char	   *nv;
					int			k;

					snprintf(sql, sizeof(sql), "update %s set ", relname);
					for (k = 1; k <= nkeys; k++)
					{
						int			is_char_type = 0;
						char	   *type;

						fn = SPI_fnumber(tupdesc, args_temp[k - 1]);
						nv = SPI_getvalue(newtuple, tupdesc, fn);
						type = SPI_gettype(tupdesc, fn);

						if ((strcmp(type, "text") && strcmp(type, "varchar") &&
							 strcmp(type, "char") && strcmp(type, "bpchar") &&
							 strcmp(type, "date") && strcmp(type, "timestamp")) == 0)
							is_char_type = 1;
#ifdef	DEBUG_QUERY
						elog(DEBUG4, "check_foreign_key Debug value %s type %s %d",
							 nv, type, is_char_type);
#endif

						/*
						 * is_char_type =1 i set ' ' for define a new value
						 */
						snprintf(sql + strlen(sql), sizeof(sql) - strlen(sql),
								 " %s = %s%s%s %s ",
								 args2[k], (is_char_type > 0) ? "'" : "",
								 nv, (is_char_type > 0) ? "'" : "", (k < nkeys) ? ", " : "");
						is_char_type = 0;
					}
					strcat(sql, " where ");

				}
				else
					/* DELETE */
					snprintf(sql, sizeof(sql), "delete from %s where ", relname);

			}

			/*
			 * For 'S'etnull action we construct UPDATE query - UPDATE
			 * _referencing_relation_ SET Fkey1 null [, Fkey2 null [...]]
			 * WHERE Fkey1 = $1 [AND Fkey2 = $2 [...]] - to set key columns in
			 * all referencing tuples to NULL.
			 */
			else if (action == 's')
			{
				snprintf(sql, sizeof(sql), "update %s set ", relname);
				for (i = 1; i <= nkeys; i++)
				{
					snprintf(sql + strlen(sql), sizeof(sql) - strlen(sql),
							 "%s = null%s",
							 args2[i], (i < nkeys) ? ", " : "");
				}
				strcat(sql, " where ");
			}

			/* Construct WHERE qual */
			for (i = 1; i <= nkeys; i++)
			{
				snprintf(sql + strlen(sql), sizeof(sql) - strlen(sql), "%s = $%d %s",
						 args2[i], i, (i < nkeys) ? "and " : "");
			}

			/* Prepare plan for query */
			pplan = SPI_prepare(sql, nkeys, argtypes);
			if (pplan == NULL)
				/* internal error */
				elog(ERROR, "check_foreign_key: SPI_prepare returned %d", SPI_result);

			/*
			 * Remember that SPI_prepare places plan in current memory context
			 * - so, we have to save plan in Top memory context for latter
			 * use.
			 */
			pplan = SPI_saveplan(pplan);
			if (pplan == NULL)
				/* internal error */
				elog(ERROR, "check_foreign_key: SPI_saveplan returned %d", SPI_result);

			plan->splan[r] = pplan;

			args2 += nkeys + 1; /* to the next relation */
		}
		plan->nplans = nrefs;
#ifdef	DEBUG_QUERY
		elog(DEBUG4, "check_foreign_key Debug Query is :  %s ", sql);
#endif
	}

	/*
	 * If UPDATE and key is not changed ...
	 */
	if (newtuple != NULL && isequal)
	{
		SPI_finish();
		return PointerGetDatum(newtuple);
	}

	/*
	 * Ok, execute prepared plan(s).
	 */
	for (r = 0; r < nrefs; r++)
	{
		/*
		 * For 'R'estrict we may to execute plan for one tuple only, for other
		 * actions - for all tuples.
		 */
		int			tcount = (action == 'r') ? 1 : 0;

		relname = args[0];

		snprintf(ident, sizeof(ident), "%s$%u", trigger->tgname, rel->rd_id);
		plan = find_plan(ident, &FPlans, &nFPlans);
		ret = SPI_execp(plan->splan[r], kvals, NULL, tcount);
		/* we have no NULLs - so we pass   ^^^^  here */

		if (ret < 0)
			ereport(ERROR,
					(errcode(ERRCODE_TRIGGERED_ACTION_EXCEPTION),
					 errmsg("SPI_execp returned %d", ret)));

		/* If action is 'R'estrict ... */
		if (action == 'r')
		{
			/* If there is tuple returned by SELECT then ... */
			if (SPI_processed > 0)
				ereport(ERROR,
						(errcode(ERRCODE_TRIGGERED_ACTION_EXCEPTION),
						 errmsg("\"%s\": tuple is referenced in \"%s\"",
								trigger->tgname, relname)));
		}
		else
		{
#ifdef REFINT_VERBOSE
			elog(NOTICE, "%s: %d tuple(s) of %s are %s",
				 trigger->tgname, SPI_processed, relname,
				 (action == 'c') ? "deleted" : "set to null");
#endif
		}
		args += nkeys + 1;		/* to the next relation */
	}

	SPI_finish();

	return PointerGetDatum((newtuple == NULL) ? trigtuple : newtuple);
}

static EPlan *
find_plan(char *ident, EPlan ** eplan, int *nplans)
{
	EPlan	   *newp;
	int			i;

	if (*nplans > 0)
	{
		for (i = 0; i < *nplans; i++)
		{
			if (strcmp((*eplan)[i].ident, ident) == 0)
				break;
		}
		if (i != *nplans)
			return (*eplan + i);
		*eplan = (EPlan *) realloc(*eplan, (i + 1) * sizeof(EPlan));
		newp = *eplan + i;
	}
	else
	{
		newp = *eplan = (EPlan *) malloc(sizeof(EPlan));
		(*nplans) = i = 0;
	}

	newp->ident = (char *) malloc(strlen(ident) + 1);
	strcpy(newp->ident, ident);
	newp->nplans = 0;
	newp->splan = NULL;
	(*nplans)++;

	return (newp);
}
extern Datum autoinc(PG_FUNCTION_ARGS);

PG_FUNCTION_INFO_V1(autoinc);

Datum
autoinc(PG_FUNCTION_ARGS)
{
	TriggerData *trigdata = (TriggerData *) fcinfo->context;
	Trigger    *trigger;		/* to get trigger name */
	int			nargs;			/* # of arguments */
	int		   *chattrs;		/* attnums of attributes to change */
	int			chnattrs = 0;	/* # of above */
	Datum	   *newvals;		/* vals of above */
	char	  **args;			/* arguments */
	char	   *relname;		/* triggered relation name */
	Relation	rel;			/* triggered relation */
	HeapTuple	rettuple = NULL;
	TupleDesc	tupdesc;		/* tuple description */
	bool		isnull;
	int			i;

	if (!CALLED_AS_TRIGGER(fcinfo))
		/* internal error */
		elog(ERROR, "not fired by trigger manager");
	if (TRIGGER_FIRED_FOR_STATEMENT(trigdata->tg_event))
		/* internal error */
		elog(ERROR, "can't process STATEMENT events");
	if (TRIGGER_FIRED_AFTER(trigdata->tg_event))
		/* internal error */
		elog(ERROR, "must be fired before event");

	if (TRIGGER_FIRED_BY_INSERT(trigdata->tg_event))
		rettuple = trigdata->tg_trigtuple;
	else if (TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
		rettuple = trigdata->tg_newtuple;
	else
		/* internal error */
		elog(ERROR, "can't process DELETE events");

	rel = trigdata->tg_relation;
	relname = SPI_getrelname(rel);

	trigger = trigdata->tg_trigger;

	nargs = trigger->tgnargs;
	if (nargs <= 0 || nargs % 2 != 0)
		/* internal error */
		elog(ERROR, "autoinc (%s): even number gt 0 of arguments was expected", relname);

	args = trigger->tgargs;
	tupdesc = rel->rd_att;

	chattrs = (int *) palloc(nargs / 2 * sizeof(int));
	newvals = (Datum *) palloc(nargs / 2 * sizeof(Datum));

	for (i = 0; i < nargs;)
	{
		int			attnum = SPI_fnumber(tupdesc, args[i]);
		int32		val;
		Datum		seqname;

		if (attnum < 0)
			ereport(ERROR,
					(errcode(ERRCODE_TRIGGERED_ACTION_EXCEPTION),
					 errmsg("\"%s\" has no attribute \"%s\"",
							relname, args[i])));

		if (SPI_gettypeid(tupdesc, attnum) != INT4OID)
			ereport(ERROR,
					(errcode(ERRCODE_TRIGGERED_ACTION_EXCEPTION),
					 errmsg("attribute \"%s\" of \"%s\" must be type INT4",
							args[i], relname)));

		val = DatumGetInt32(SPI_getbinval(rettuple, tupdesc, attnum, &isnull));

		if (!isnull && val != 0)
		{
			i += 2;
			continue;
		}

		i++;
		chattrs[chnattrs] = attnum;
		seqname = DirectFunctionCall1(textin,
									  CStringGetDatum(args[i]));
		newvals[chnattrs] = DirectFunctionCall1(nextval, seqname);
		/* nextval now returns int64; coerce down to int32 */
		newvals[chnattrs] = Int32GetDatum((int32) DatumGetInt64(newvals[chnattrs]));
		if (DatumGetInt32(newvals[chnattrs]) == 0)
		{
			newvals[chnattrs] = DirectFunctionCall1(nextval, seqname);
			newvals[chnattrs] = Int32GetDatum((int32) DatumGetInt64(newvals[chnattrs]));
		}
		pfree(DatumGetTextP(seqname));
		chnattrs++;
		i++;
	}

	if (chnattrs > 0)
	{
		rettuple = SPI_modifytuple(rel, rettuple, chnattrs, chattrs, newvals, NULL);
		if (rettuple == NULL)
			/* internal error */
			elog(ERROR, "autoinc (%s): %d returned by SPI_modifytuple",
				 relname, SPI_result);
	}

	pfree(relname);
	pfree(chattrs);
	pfree(newvals);

	return PointerGetDatum(rettuple);
}

/*
 * Turning a string to bytea.  No escape, quote, nothing.
 */
PG_FUNCTION_INFO_V1(gp_str2bytea); 
Datum
gp_str2bytea(PG_FUNCTION_ARGS)
{
    Datum d = PG_GETARG_DATUM(0);
    return d;
}


/* table_functions test */
PG_FUNCTION_INFO_V1(multiset_scalar_null);
PG_FUNCTION_INFO_V1(multiset_scalar_value);
PG_FUNCTION_INFO_V1(multiset_scalar_tuple);
PG_FUNCTION_INFO_V1(multiset_setof_null);
PG_FUNCTION_INFO_V1(multiset_setof_value);
PG_FUNCTION_INFO_V1(multiset_materialize_good);
PG_FUNCTION_INFO_V1(multiset_materialize_bad);
PG_FUNCTION_INFO_V1(multiset_example);

Datum
multiset_scalar_null(PG_FUNCTION_ARGS)
{
	PG_RETURN_NULL();
}

Datum
multiset_scalar_value(PG_FUNCTION_ARGS)
{
	AnyTable             scan;
	HeapTuple            tuple;
	TupleDesc            in_tupdesc;
	Datum                values[1];
	bool				 nulls[1];
	int					 result;

	/* 
	 * Sanity checking, shouldn't occur if our CREATE FUNCTION in SQL is done
	 * correctly.
	 */
	if (PG_NARGS() < 1 || PG_ARGISNULL(0))
		elog(ERROR, "invalid invocation of multiset_example");
	scan = PG_GETARG_ANYTABLE(0);  /* Should be the first parameter */


	/* Get the next value from the input scan */
	in_tupdesc  = AnyTable_GetTupleDesc(scan);
	tuple       = AnyTable_GetNextTuple(scan);

	/* check for end of scan */
	if (tuple == NULL)
		PG_RETURN_NULL();

	/*
	 * We expect an input of one integer column for this stupid 
	 * table function, if that is not what we got then complain.
	 */
	if (in_tupdesc->natts != 1 ||
		in_tupdesc->attrs[0]->atttypid != INT4OID)
	{
		ereport(ERROR, 
				(errcode(ERRCODE_CANNOT_COERCE),
				 errmsg("invalid input tuple for function multiset_example"),
				 errhint("expected (integer, text) ")));
	}

	/* -----
	 * Extract fields from input tuple, there are several possibilities
	 * depending on if we want to fetch the rows by name, by number, or extract
	 * the full tuple contents.
	 *
	 *    - values[0] = GetAttributeByName(tuple->t_data, "a", &nulls[0]);
	 *    - values[0] = GetAttributeByNum(tuple->t_data, 1, &nulls[0]);
	 *    - heap_deform_tuple(tuple, in_tupdesc, values, nulls);
	 *
	 * In this case we have chosen to use getAttributeByNum
	 */
//	values[0] = GetAttributeByNum(tuple->t_data, 1, &nulls[0]);
	values[0] = heap_getattr(tuple, 1, in_tupdesc, &nulls[0]);

	/* Handle NULL */
	if (nulls[0])
		PG_RETURN_NULL();

	/* 
	 * Convert the Datum to an integer so we can operate on it.
	 * 
	 * Since we are just going to return it directly we could skip this step,
	 * and simply call PG_RETURN_DATUM(values[0]), but this is more illustrative.
	 */
	result = DatumGetInt32(values[0]);

	PG_RETURN_INT32(result);
}

Datum
multiset_scalar_tuple(PG_FUNCTION_ARGS)
{
	ReturnSetInfo *rsi;
	TupleDesc	tupdesc;
	HeapTuple	tuple;
	Datum		values[2];
	bool		nulls[2];
	Datum		result;

	/* Double check that the output tupledesc is what we expect */
	rsi		= (ReturnSetInfo *) fcinfo->resultinfo;
	tupdesc	= rsi->expectedDesc;

	if (tupdesc->natts				 != 2												||
		(tupdesc->attrs[0]->atttypid != INT4OID && !tupdesc->attrs[0]->attisdropped)	||
		(tupdesc->attrs[1]->atttypid != TEXTOID && !tupdesc->attrs[1]->attisdropped))
	{
		ereport(ERROR, 
				(errcode(ERRCODE_CANNOT_COERCE),
				 errmsg("invalid output tupledesc for function multiset_scalar_tuple"),
				 errhint("Expected (integer, text).")));
	}

	/* Populate an output tuple. */
	values[0] = Int32GetDatum(1);
	values[1] = CStringGetTextDatum("Example");
	nulls[0] = nulls[1] = false;
	tuple = heap_form_tuple(tupdesc, values, nulls);
	result = HeapTupleGetDatum(tuple);

	PG_RETURN_DATUM(result);
}

Datum
multiset_setof_null(PG_FUNCTION_ARGS)
{
	FuncCallContext		*fctx;
	ReturnSetInfo 		*rsi;

	if (SRF_IS_FIRSTCALL())
	{
		fctx = SRF_FIRSTCALL_INIT();
	}
	fctx = SRF_PERCALL_SETUP();
	
	/* This is just one way we might test that we are done: */
	if (fctx->call_cntr < 3)
	{
		/* 
		 * set returning functions shouldn't return NULL results, in order to
		 * due so you need to sidestep the normal SRF_RETURN_NEXT mechanism.
		 * This is an error-condition test, not correct coding practices.
		 */
		rsi	= (ReturnSetInfo *) fcinfo->resultinfo;
		rsi->isDone = ExprMultipleResult;
		fctx->call_cntr++; /* would happen automatically with SRF_RETURN_NEXT */
		PG_RETURN_NULL();  /* see above: only for testing, don't do this */
	}
	else
	{
		/* do any user specific cleanup on last call */
		SRF_RETURN_DONE(fctx);
	}
}

Datum
multiset_setof_value(PG_FUNCTION_ARGS)
{
	FuncCallContext		*fctx;

	if (SRF_IS_FIRSTCALL())
	{
		fctx = SRF_FIRSTCALL_INIT();
	}
	fctx = SRF_PERCALL_SETUP();
	
	/* This is just one way we might test that we are done: */
	if (fctx->call_cntr < 3)
	{
		SRF_RETURN_NEXT(fctx, Int32GetDatum(fctx->call_cntr));
	}
	else
	{
		/* do any user specific cleanup on last call */
		SRF_RETURN_DONE(fctx);
	}
}

Datum
multiset_materialize_good(PG_FUNCTION_ARGS)
{
	FuncCallContext		*fctx;
	ReturnSetInfo 		*rsi = (ReturnSetInfo *) fcinfo->resultinfo;

	/*
	 * To return SFRM_Materialize the correct convention is to first
	 * check if this is an allowed mode.  Currently it is not, so we
	 * expect this to raise an error.
	 */
	if (!rsi || !IsA(rsi, ReturnSetInfo) ||
		(rsi->allowedModes & SFRM_Materialize) == 0 ||
		rsi->expectedDesc == NULL)
	{
		ereport(ERROR,
				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
				 errmsg("set-valued function called in context that "
						"cannot accept a set")));
	}


	if (SRF_IS_FIRSTCALL())
	{
		fctx = SRF_FIRSTCALL_INIT();
	}
	fctx = SRF_PERCALL_SETUP();
	SRF_RETURN_DONE(fctx);
}

Datum
multiset_materialize_bad(PG_FUNCTION_ARGS)
{
	ReturnSetInfo *rsi = (ReturnSetInfo *) fcinfo->resultinfo;

	/* 
	 * This function is "bad" because it does not check if the caller 
	 * supports SFRM_Materialize before trying to return a materialized
	 * set.
	 */
	rsi->returnMode = SFRM_Materialize;
	PG_RETURN_NULL();
}


Datum
multiset_example(PG_FUNCTION_ARGS)
{
	FuncCallContext		*fctx;
	ReturnSetInfo 		*rsi;
	AnyTable             scan;
	HeapTuple            tuple;
	TupleDesc            in_tupdesc;
	TupleDesc            out_tupdesc;
	Datum                tup_datum;
	Datum                values[2];
	bool				 nulls[2];

	/* 
	 * Sanity checking, shouldn't occur if our CREATE FUNCTION in SQL is done
	 * correctly.
	 */
	if (PG_NARGS() < 1 || PG_ARGISNULL(0))
		elog(ERROR, "invalid invocation of multiset_example");
	scan = PG_GETARG_ANYTABLE(0);  /* Should be the first parameter */

	/* Basic set-returning function (SRF) protocol, setup the context */
	if (SRF_IS_FIRSTCALL())
	{
		fctx = SRF_FIRSTCALL_INIT();
	}
	fctx = SRF_PERCALL_SETUP();

	/* Get the next value from the input scan */
	rsi			= (ReturnSetInfo *) fcinfo->resultinfo;
	out_tupdesc = rsi->expectedDesc;
	in_tupdesc  = AnyTable_GetTupleDesc(scan);
	tuple       = AnyTable_GetNextTuple(scan);

	/* check for end of scan */
	if (tuple == NULL)
		SRF_RETURN_DONE(fctx);

	/*
	 * We expect an input/output of two columns (int, text) for this stupid 
	 * table function, if that is not what we got then complain.
	 */
	if (in_tupdesc->natts			   != 2				||
		in_tupdesc->attrs[0]->atttypid != INT4OID		||
		in_tupdesc->attrs[1]->atttypid != TEXTOID)
	{
		ereport(ERROR, 
				(errcode(ERRCODE_CANNOT_COERCE),
				 errmsg("invalid input tuple for function multiset_example"),
				 errhint("expected (integer, text) ")));
	}

	/* For output tuple we also check for possibility of dropped columns */
	if (out_tupdesc->natts				 != 2			||
		(out_tupdesc->attrs[0]->atttypid != INT4OID		&& 
		 !out_tupdesc->attrs[0]->attisdropped)			||
		(out_tupdesc->attrs[1]->atttypid != TEXTOID		&&
		 !out_tupdesc->attrs[1]->attisdropped))
	{
		ereport(ERROR, 
				(errcode(ERRCODE_CANNOT_COERCE),
				 errmsg("invalid output tuple for function multiset_example"),
				 errhint("expected (integer, text) ")));
	}


	/* -----
	 * Extract fields from input tuple, there are several possibilities
	 * depending on if we want to fetch the rows by name, by number, or extract
	 * the full tuple contents.
	 *
	 *    - values[0] = GetAttributeByName(tuple->t_data, "a", &nulls[0]);
	 *    - values[0] = GetAttributeByNum(tuple->t_data, 0, &nulls[0]);
	 *    - heap_deform_tuple(tuple, in_tupdesc, values, nulls);
	 *
	 * In this case we have chosen to do the whole tuple at once.
	 */
	heap_deform_tuple(tuple, in_tupdesc, values, nulls);

	/* 
	 * Since we have already validated types we can form this directly
	 * into our output tuple without additional conversion.
	 */
	tuple = heap_form_tuple(out_tupdesc, values, nulls);

	/* 
	 * Final output must always be a Datum, so convert the tuple as required
	 * by the API.
	 */
	tup_datum = HeapTupleGetDatum(tuple);

	/* Extract values from input tuple, build output tuple */
	SRF_RETURN_NEXT(fctx, tup_datum);
}

/*
 * sessionize
 */
typedef struct session_state {
	int			id;
	Timestamp	time;
	int			counter;
} session_state;

PG_FUNCTION_INFO_V1(sessionize);
Datum
sessionize(PG_FUNCTION_ARGS)
{
	FuncCallContext		*fctx;
	ReturnSetInfo 		*rsi;
	AnyTable             scan;
	HeapTuple            tuple;
	TupleDesc            in_tupdesc;
	TupleDesc            out_tupdesc;
	Datum                tup_datum;
	Datum                values[3];
	bool				 nulls[3];
	session_state       *state;
	int                  newId;
	Timestamp            newTime;
	Interval            *threshold;

	/* 
	 * Sanity checking, shouldn't occur if our CREATE FUNCTION in SQL is done
	 * correctly.
	 */
	if (PG_NARGS() != 2 || PG_ARGISNULL(0) || PG_ARGISNULL(1))
		elog(ERROR, "invalid invocation of sessionize");
	scan = PG_GETARG_ANYTABLE(0);  /* Should be the first parameter */
	threshold = PG_GETARG_INTERVAL_P(1); 

	/* Basic set-returning function (SRF) protocol, setup the context */
	if (SRF_IS_FIRSTCALL())
	{
		MemoryContext oldcontext;

		fctx = SRF_FIRSTCALL_INIT();

		oldcontext = MemoryContextSwitchTo(fctx->multi_call_memory_ctx);
		
		state = (session_state*) palloc0(sizeof(session_state));
		fctx->user_fctx = (void*) state;
		state->id = -9999;  /* gross hack: stupid special value for demo */

		MemoryContextSwitchTo(oldcontext);
	}
	fctx = SRF_PERCALL_SETUP();
	state = (session_state*) fctx->user_fctx;

	/* Get the next value from the input scan */
	rsi			= (ReturnSetInfo *) fcinfo->resultinfo;
	out_tupdesc = rsi->expectedDesc;
	in_tupdesc  = AnyTable_GetTupleDesc(scan);
	tuple       = AnyTable_GetNextTuple(scan);

	/* check for end of scan */
	if (tuple == NULL)
		SRF_RETURN_DONE(fctx);

	/*
	 * We expect an input/output of two columns (int, text) for this stupid 
	 * table function, if that is not what we got then complain.
	 */
	if (in_tupdesc->natts			   != 2				||
		in_tupdesc->attrs[0]->atttypid != INT4OID		||
		in_tupdesc->attrs[1]->atttypid != TIMESTAMPOID)
	{
		ereport(ERROR, 
				(errcode(ERRCODE_CANNOT_COERCE),
				 errmsg("invalid input tuple for function sessionize"),
				 errhint("expected (integer, timestamp) ")));
	}

	/* For output tuple we also check for possibility of dropped columns */
	if (out_tupdesc->natts				 != 3			||
		(out_tupdesc->attrs[0]->atttypid != INT4OID		&& 
		 !out_tupdesc->attrs[0]->attisdropped)			||
		(out_tupdesc->attrs[1]->atttypid != TIMESTAMPOID &&
		 !out_tupdesc->attrs[1]->attisdropped)			||
		(out_tupdesc->attrs[2]->atttypid != INT4OID     &&
		 !out_tupdesc->attrs[2]->attisdropped))
	{
		ereport(ERROR, 
				(errcode(ERRCODE_CANNOT_COERCE),
				 errmsg("invalid output tuple for function sessionize"),
				 errhint("expected (integer, timestamp, integer) ")));
	}


	/* -----
	 * Extract fields from input tuple, there are several possibilities
	 * depending on if we want to fetch the rows by name, by number, or extract
	 * the full tuple contents.
	 *
	 *    - values[0] = GetAttributeByName(tuple->t_data, "a", &nulls[0]);
	 *    - values[0] = GetAttributeByNum(tuple->t_data, 0, &nulls[0]);
	 *    - heap_deform_tuple(tuple, in_tupdesc, values, nulls);
	 *
	 * In this case we have chosen to do the whole tuple at once.
	 */
	heap_deform_tuple(tuple, in_tupdesc, values, nulls);
	newId = DatumGetInt32(values[0]);
	newTime = DatumGetTimestamp(values[1]);

	/* just skip null input */
	if (nulls[0] || nulls[1])
	{
		nulls[2] = true;
	}
	else
	{
		nulls[2] = false;

		/* handle state transition */
		if (newId == state->id)
		{
			Datum d;

			/* Calculate old timestamp + interval */
			d = DirectFunctionCall2(timestamp_pl_interval, 
									TimestampGetDatum(state->time),
									IntervalPGetDatum(threshold));
			
			/* if that is less than new interval then bump counter */
			d = DirectFunctionCall2(timestamp_lt, d, TimestampGetDatum(newTime));
		
			if (DatumGetBool(d))
				state->counter++;
			state->time = newTime;		
		}
		else
		{
			state->id	   = newId;
			state->time	   = newTime;
			state->counter = 1;
		}
	}

	/* 
	 * Since we have already validated types we can form this directly
	 * into our output tuple without additional conversion.
	 */
	values[2] = Int32GetDatum(state->counter);
	tuple = heap_form_tuple(out_tupdesc, values, nulls);

	/* 
	 * Final output must always be a Datum, so convert the tuple as required
	 * by the API.
	 */
	tup_datum = HeapTupleGetDatum(tuple);

	/* Extract values from input tuple, build output tuple */
	SRF_RETURN_NEXT(fctx, tup_datum);
}



/*
 * The absolute simplest of describe functions, ignore input and always return
 * the same tuple descriptor.  This is effectively the same as statically 
 * defining the type in the CREATE TABLE definition, but this time we have
 * pushed it into a dynamic call time resolution context.
 */
PG_FUNCTION_INFO_V1(describe);
Datum 
describe(PG_FUNCTION_ARGS)
{
	FuncExpr *fexpr;
	TupleDesc tupdesc;

	if (PG_NARGS() != 1 || PG_ARGISNULL(0))
		elog(ERROR, "invalid invocation of describe");	

	fexpr = (FuncExpr*) PG_GETARG_POINTER(0);
	Insist(IsA(fexpr, FuncExpr));   /* Assert we got what we expected */
	
	/* Build a result tuple descriptor */
	tupdesc = CreateTemplateTupleDesc(3, false);
	TupleDescInitEntry(tupdesc, (AttrNumber) 1, "id", INT4OID, -1, 0);
	TupleDescInitEntry(tupdesc, (AttrNumber) 2, "time", TIMESTAMPOID, -1, 0);
	TupleDescInitEntry(tupdesc, (AttrNumber) 3, "sessionnum", INT4OID, -1, 0);
	
	PG_RETURN_POINTER(tupdesc);
}



PG_FUNCTION_INFO_V1(project);

Datum
project(PG_FUNCTION_ARGS)
{
	FuncCallContext		*fctx;
	ReturnSetInfo		*rsi;
	AnyTable			 scan;
	HeapTuple			 tuple;
	TupleDesc			 in_tupdesc;
	TupleDesc			 out_tupdesc;
	Datum				 tup_datum;
	Datum				 values[1];
	bool				 nulls[1];
	int					 position;

	/*
	 * Sanity checking, shouldn't occur if our CREATE FUNCTION in SQL is done
	 * correctly.
	 */
	if (PG_NARGS() != 2 || PG_ARGISNULL(0) || PG_ARGISNULL(1))
		elog(ERROR, "invalid invocation of project");
	scan = PG_GETARG_ANYTABLE(0);  /* Should be the first parameter */
	position = PG_GETARG_INT32(1);

	/* Basic set-returning function (SRF) protocol, setup the context */
	if (SRF_IS_FIRSTCALL())
	{
		fctx = SRF_FIRSTCALL_INIT();
	}
	fctx = SRF_PERCALL_SETUP();

	/* Get the next value from the input scan */
	rsi			= (ReturnSetInfo *) fcinfo->resultinfo;
	out_tupdesc = rsi->expectedDesc;
	in_tupdesc  = AnyTable_GetTupleDesc(scan);
	tuple       = AnyTable_GetNextTuple(scan);

	/* Based on what the describe callback should have setup */
	Insist(position > 0 && position <= in_tupdesc->natts);
	Insist(out_tupdesc->natts == 1);
	Insist(out_tupdesc->attrs[0]->atttypid == in_tupdesc->attrs[position-1]->atttypid);
	
	/* check for end of scan */
	if (tuple == NULL)
		SRF_RETURN_DONE(fctx);

	/* -----
	 * Extract fields from input tuple, there are several possibilities
	 * depending on if we want to fetch the rows by name, by number, or extract
	 * the full tuple contents.
	 *
	 *    - values[0] = GetAttributeByName(tuple->t_data, "a", &nulls[0]);
	 *    - values[0] = GetAttributeByNum(tuple->t_data, 0, &nulls[0]);
	 *    - heap_deform_tuple(tuple, in_tupdesc, values, nulls);
	 *
	 * In this case we have chosen to do extract by position 
	 */
	values[0] = GetAttributeByNum(tuple->t_data, (AttrNumber) position, &nulls[0]);

	/* Construct the output tuple and convert to a datum */
	tuple = heap_form_tuple(out_tupdesc, values, nulls);
	tup_datum = HeapTupleGetDatum(tuple);

	/* Return the next result */
	SRF_RETURN_NEXT(fctx, tup_datum);
}


/*
 * A more dynamic describe function that produces different results depending
 * on what sort of input it receives.
 */
PG_FUNCTION_INFO_V1(project_describe);
Datum
project_describe(PG_FUNCTION_ARGS)
{
	FuncExpr			*fexpr;
	List				*fargs;
	ListCell			*lc;
	Oid					*argtypes;
	int					 numargs;
	TableValueExpr		*texpr;
	Query				*qexpr;
	TupleDesc			 tdesc;
	TupleDesc			 odesc;
	int					 avalue;
	bool				 isnull;
	int					 i;

	/* Fetch and validate input */
	if (PG_NARGS() != 1 || PG_ARGISNULL(0))
		elog(ERROR, "invalid invocation of project_describe");

	fexpr = (FuncExpr*) PG_GETARG_POINTER(0);
	Insist(IsA(fexpr, FuncExpr));   /* Assert we got what we expected */
	
	/*
	 * We should know the type information of the arguments of our calling
	 * function, but this demonstrates how we could determine that if we
	 * didn't already know.
	 */
	fargs = fexpr->args;
	numargs = list_length(fargs);
	argtypes = palloc(sizeof(Oid)*numargs);
	i = 0;
	foreach(lc, fargs)
	{
		Node *arg = lfirst(lc);
		argtypes[i++] = exprType(arg);
	}
	
	/* --------
	 * Given that we believe we know that this function is tied to exactly
	 * one implementation, lets verify that the above types are what we 
	 * were expecting:
	 *   - two arguments
	 *   - first argument "anytable"
	 *   - second argument "text"
	 * --------
	 */
	Insist(numargs == 2);
	Insist(argtypes[0] == ANYTABLEOID);
	Insist(argtypes[1] == INT4OID);

	/* Now get the tuple descriptor for the ANYTABLE we received */
	texpr = (TableValueExpr*) linitial(fargs);
	Insist(IsA(texpr, TableValueExpr));  /* double check that cast */
	
	qexpr = (Query*) texpr->subquery;
	Insist(IsA(qexpr, Query));

	tdesc = ExecCleanTypeFromTL(qexpr->targetList, false);
	
	/* 
	 * The intent of this table function is that it returns the Nth column
	 * from the input, which requires us to know what N is.  We get N from
	 * the second parameter to the table function.
	 *
	 * Try to evaluate that argument to a constant value.
	 */
	avalue = DatumGetInt32(ExecEvalFunctionArgToConst(fexpr, 1, &isnull));
	if (isnull)
		elog(ERROR, "unable to resolve type for function");

	if (avalue < 1 || avalue > tdesc->natts)
		elog(ERROR, "invalid column position %d", avalue);

	/* Build an output tuple a single column based on the column number above */
	odesc = CreateTemplateTupleDesc(1, false);
	TupleDescInitEntry(odesc, 1, 
					   NameStr(tdesc->attrs[avalue-1]->attname),
					   tdesc->attrs[avalue-1]->atttypid,
					   tdesc->attrs[avalue-1]->atttypmod,
					   0);

	/* Finally return that tupdesc */
	PG_RETURN_POINTER(odesc);
}

/*
 *
 */
PG_FUNCTION_INFO_V1(userdata_project);
Datum
userdata_project(PG_FUNCTION_ARGS)
{
	FuncCallContext		*fctx;
	ReturnSetInfo		*rsi;
	AnyTable			 scan;
	HeapTuple			 tuple;
	TupleDesc			 out_tupdesc;
	Datum				 tup_datum;
	Datum				 values[1];
	bool				 nulls[1];
	bytea				*userdata;
	char				*message;

	/*
	 * Sanity checking, shouldn't occur if our CREATE FUNCTION in SQL is done
	 * correctly.
	 */
	if (PG_NARGS() != 1 || PG_ARGISNULL(0) || PG_ARGISNULL(1))
		elog(ERROR, "invalid invocation of userdata_project");
	scan = PG_GETARG_ANYTABLE(0);  /* Should be the first parameter */
	if (SRF_IS_FIRSTCALL())
	{
		fctx = SRF_FIRSTCALL_INIT();
	}
	fctx = SRF_PERCALL_SETUP();

	/* Get the next value from the input scan */
	rsi			= (ReturnSetInfo *) fcinfo->resultinfo;
	out_tupdesc = rsi->expectedDesc;
	tuple       = AnyTable_GetNextTuple(scan);
	if (tuple == NULL)
		SRF_RETURN_DONE(fctx);

	/* Receive message from describe function */
	userdata = TF_GET_USERDATA();
	if (userdata != NULL)
	{
		message = (char *) VARDATA(userdata);
		values[0] = CStringGetTextDatum(message);
		nulls[0] = false;
	}
	else
	{
		values[0] = (Datum) 0;
		nulls[0] = true;
	}
	/* Construct the output tuple and convert to a datum */
	tuple = heap_form_tuple(out_tupdesc, values, nulls);
	tup_datum = HeapTupleGetDatum(tuple);

	/* Return the next result */
	SRF_RETURN_NEXT(fctx, tup_datum);
}

PG_FUNCTION_INFO_V1(userdata_describe);
Datum
userdata_describe(PG_FUNCTION_ARGS)
{
	FuncExpr *fexpr;
	TupleDesc tupdesc;
	bytea	   *userdata;
	size_t		bytes;
	const char *message = "copied data from describe function";

	/* Fetch and validate input */
	if (PG_NARGS() != 1 || PG_ARGISNULL(0))
		elog(ERROR, "invalid invocation of userdata_describe");	

	fexpr = (FuncExpr*) PG_GETARG_POINTER(0);
	Insist(IsA(fexpr, FuncExpr));   /* Assert we got what we expected */

	/* Build a result tuple descriptor */
	tupdesc = CreateTemplateTupleDesc(1, false);
	TupleDescInitEntry(tupdesc, (AttrNumber) 1, "message", TEXTOID, -1, 0);

	/* Prepare user data */
	bytes = VARHDRSZ + 256;
	userdata = (bytea *) palloc0(bytes);
	SET_VARSIZE(userdata, bytes);
	strcpy(VARDATA(userdata), message);

	/* Set to send */
	TF_SET_USERDATA(userdata);

	PG_RETURN_POINTER(tupdesc);
}

/*
 * This is do-nothing table function that passes the input relation
 * to the output relation without any modification.
 */
PG_FUNCTION_INFO_V1(noop_project);
Datum
noop_project(PG_FUNCTION_ARGS)
{
	AnyTable			scan;
	FuncCallContext	   *fctx;
	ReturnSetInfo	   *rsi;
	HeapTuple			tuple;

	scan = PG_GETARG_ANYTABLE(0);
	if (SRF_IS_FIRSTCALL())
	{
		fctx = SRF_FIRSTCALL_INIT();
	}
	fctx = SRF_PERCALL_SETUP();
	rsi = (ReturnSetInfo *) fcinfo->resultinfo;
	tuple = AnyTable_GetNextTuple(scan);
	if (!tuple)
		SRF_RETURN_DONE(fctx);

	SRF_RETURN_NEXT(fctx, HeapTupleGetDatum(tuple));
}

/*
 * Simply invoke CheckAuthTimeConstraints from libpq/auth.h with given rolname.
 */
PG_FUNCTION_INFO_V1(check_auth_time_constraints);
Datum
check_auth_time_constraints(PG_FUNCTION_ARGS)
{
	char			*rolname = PG_GETARG_CSTRING(0);
	TimestampTz 	timestamp = PG_GETARG_TIMESTAMPTZ(1);
	/*
	 * For the sake of unit testing, we must ensure that the role information
	 * is accessible to the backend process. This function call will ensure
	 * the role information is reloaded. This is a moot point
	 * for the traditional auth. checking where this data already resides in the
	 * PostmasterContext. For more information, see force_load_role().
	 */
	force_load_role();
	PG_RETURN_BOOL(check_auth_time_constraints_internal(rolname, timestamp));
}

/*
 * Checks if memory limit of resource queue is in sync across
 * shared memory and catalog.
 * This function should ONLY be used for unit testing.
 */
PG_FUNCTION_INFO_V1(checkResourceQueueMemoryLimits);
Datum 
checkResourceQueueMemoryLimits(PG_FUNCTION_ARGS)
{
	char *queueName = PG_GETARG_CSTRING(0);
	Oid queueId;
	ResQueue queue;
	double v1, v2;

	if (queueName == NULL)
		return (Datum)0;

	/* get OID for queue */
	queueId = GetResQueueIdForName(queueName);

	if (queueId == InvalidOid)
		return (Datum)0;

	/* ResQueueHashFind needs a lock */
	LWLockAcquire(ResQueueLock, LW_EXCLUSIVE);

	/* get shared memory version of queue */
	queue = ResQueueHashFind(queueId);

	LWLockRelease(ResQueueLock);

	if (!queue)
		return (Datum) 0;

	v1 = ceil(queue->limits[RES_MEMORY_LIMIT].threshold_value);
	v2 = ceil((double) ResourceQueueGetMemoryLimitInCatalog(queueId));

	PG_RETURN_BOOL(v1 == v2);
}

/*
 * Check if Relation has the valid information after cache invalidation.
 */
PG_FUNCTION_INFO_V1(checkRelationAfterInvalidation);
Datum
checkRelationAfterInvalidation(PG_FUNCTION_ARGS)
{
	Relation relation;
	struct RelationNodeInfo nodeinfo;

	/* The relation is arbitrary.  Any "unnailed" relation is ok */
	relation = relation_open(LanguageRelationId, AccessShareLock);
	RelationFetchGpRelationNodeForXLog(relation);
	memcpy(&nodeinfo,
		   &relation->rd_segfile0_relationnodeinfo,
		   sizeof(struct RelationNodeInfo));

	/* Invalidation messages should not blow persistent table info */
	RelationCacheInvalidate();
	if (memcmp(&nodeinfo,
			   &relation->rd_segfile0_relationnodeinfo,
			   sizeof(struct RelationNodeInfo)) != 0)
		elog(ERROR, "node info does not match");

	relation_close(relation, AccessShareLock);

	PG_RETURN_BOOL(true);
}

#ifndef PG_HAVE_ATOMIC_FLAG_SIMULATION
static void
test_atomic_flag(void)
{
	pg_atomic_flag flag;

	pg_atomic_init_flag(&flag);

	if (!pg_atomic_unlocked_test_flag(&flag))
		elog(ERROR, "flag: unexpectedly set");

	if (!pg_atomic_test_set_flag(&flag))
		elog(ERROR, "flag: couldn't set");

	if (pg_atomic_unlocked_test_flag(&flag))
		elog(ERROR, "flag: unexpectedly unset");

	if (pg_atomic_test_set_flag(&flag))
		elog(ERROR, "flag: set spuriously #2");

	pg_atomic_clear_flag(&flag);

	if (!pg_atomic_unlocked_test_flag(&flag))
		elog(ERROR, "flag: unexpectedly set #2");

	if (!pg_atomic_test_set_flag(&flag))
		elog(ERROR, "flag: couldn't set");

	pg_atomic_clear_flag(&flag);
}
#endif   /* PG_HAVE_ATOMIC_FLAG_SIMULATION */

static void
test_atomic_uint32(void)
{
	pg_atomic_uint32 var;
	uint32		expected;
	int			i;

	pg_atomic_init_u32(&var, 0);

	if (pg_atomic_read_u32(&var) != 0)
		elog(ERROR, "atomic_read_u32() #1 wrong");

	pg_atomic_write_u32(&var, 3);

	if (pg_atomic_read_u32(&var) != 3)
		elog(ERROR, "atomic_read_u32() #2 wrong");

	if (pg_atomic_fetch_add_u32(&var, 1) != 3)
		elog(ERROR, "atomic_fetch_add_u32() #1 wrong");

	if (pg_atomic_fetch_sub_u32(&var, 1) != 4)
		elog(ERROR, "atomic_fetch_sub_u32() #1 wrong");

	if (pg_atomic_sub_fetch_u32(&var, 3) != 0)
		elog(ERROR, "atomic_sub_fetch_u32() #1 wrong");

	if (pg_atomic_add_fetch_u32(&var, 10) != 10)
		elog(ERROR, "atomic_add_fetch_u32() #1 wrong");

	if (pg_atomic_exchange_u32(&var, 5) != 10)
		elog(ERROR, "pg_atomic_exchange_u32() #1 wrong");

	if (pg_atomic_exchange_u32(&var, 0) != 5)
		elog(ERROR, "pg_atomic_exchange_u32() #0 wrong");

	/* test around numerical limits */
	if (pg_atomic_fetch_add_u32(&var, INT_MAX) != 0)
		elog(ERROR, "pg_atomic_fetch_add_u32() #2 wrong");

	if (pg_atomic_fetch_add_u32(&var, INT_MAX) != INT_MAX)
		elog(ERROR, "pg_atomic_add_fetch_u32() #3 wrong");

	pg_atomic_fetch_add_u32(&var, 1);	/* top up to UINT_MAX */

	if (pg_atomic_read_u32(&var) != UINT_MAX)
		elog(ERROR, "atomic_read_u32() #2 wrong");

	if (pg_atomic_fetch_sub_u32(&var, INT_MAX) != UINT_MAX)
		elog(ERROR, "pg_atomic_fetch_sub_u32() #2 wrong");

	if (pg_atomic_read_u32(&var) != (uint32) INT_MAX + 1)
		elog(ERROR, "atomic_read_u32() #3 wrong: %u", pg_atomic_read_u32(&var));

	expected = pg_atomic_sub_fetch_u32(&var, INT_MAX);
	if (expected != 1)
		elog(ERROR, "pg_atomic_sub_fetch_u32() #3 wrong: %u", expected);

	pg_atomic_sub_fetch_u32(&var, 1);

	/* fail exchange because of old expected */
	expected = 10;
	if (pg_atomic_compare_exchange_u32(&var, &expected, 1))
		elog(ERROR, "atomic_compare_exchange_u32() changed value spuriously");

	/* CAS is allowed to fail due to interrupts, try a couple of times */
	for (i = 0; i < 1000; i++)
	{
		expected = 0;
		if (!pg_atomic_compare_exchange_u32(&var, &expected, 1))
			break;
	}
	if (i == 1000)
		elog(ERROR, "atomic_compare_exchange_u32() never succeeded");
	if (pg_atomic_read_u32(&var) != 1)
		elog(ERROR, "atomic_compare_exchange_u32() didn't set value properly");

	pg_atomic_write_u32(&var, 0);

	/* try setting flagbits */
	if (pg_atomic_fetch_or_u32(&var, 1) & 1)
		elog(ERROR, "pg_atomic_fetch_or_u32() #1 wrong");

	if (!(pg_atomic_fetch_or_u32(&var, 2) & 1))
		elog(ERROR, "pg_atomic_fetch_or_u32() #2 wrong");

	if (pg_atomic_read_u32(&var) != 3)
		elog(ERROR, "invalid result after pg_atomic_fetch_or_u32()");

	/* try clearing flagbits */
	if ((pg_atomic_fetch_and_u32(&var, ~2) & 3) != 3)
		elog(ERROR, "pg_atomic_fetch_and_u32() #1 wrong");

	if (pg_atomic_fetch_and_u32(&var, ~1) != 1)
		elog(ERROR, "pg_atomic_fetch_and_u32() #2 wrong: is %u",
			 pg_atomic_read_u32(&var));
	/* no bits set anymore */
	if (pg_atomic_fetch_and_u32(&var, ~0) != 0)
		elog(ERROR, "pg_atomic_fetch_and_u32() #3 wrong");
}

#ifdef PG_HAVE_ATOMIC_U64_SUPPORT
static void
test_atomic_uint64(void)
{
	pg_atomic_uint64 var;
	uint64		expected;
	int			i;

	pg_atomic_init_u64(&var, 0);

	if (pg_atomic_read_u64(&var) != 0)
		elog(ERROR, "atomic_read_u64() #1 wrong");

	pg_atomic_write_u64(&var, 3);

	if (pg_atomic_read_u64(&var) != 3)
		elog(ERROR, "atomic_read_u64() #2 wrong");

	if (pg_atomic_fetch_add_u64(&var, 1) != 3)
		elog(ERROR, "atomic_fetch_add_u64() #1 wrong");

	if (pg_atomic_fetch_sub_u64(&var, 1) != 4)
		elog(ERROR, "atomic_fetch_sub_u64() #1 wrong");

	if (pg_atomic_sub_fetch_u64(&var, 3) != 0)
		elog(ERROR, "atomic_sub_fetch_u64() #1 wrong");

	if (pg_atomic_add_fetch_u64(&var, 10) != 10)
		elog(ERROR, "atomic_add_fetch_u64() #1 wrong");

	if (pg_atomic_exchange_u64(&var, 5) != 10)
		elog(ERROR, "pg_atomic_exchange_u64() #1 wrong");

	if (pg_atomic_exchange_u64(&var, 0) != 5)
		elog(ERROR, "pg_atomic_exchange_u64() #0 wrong");

	/* fail exchange because of old expected */
	expected = 10;
	if (pg_atomic_compare_exchange_u64(&var, &expected, 1))
		elog(ERROR, "atomic_compare_exchange_u64() changed value spuriously");

	/* CAS is allowed to fail due to interrupts, try a couple of times */
	for (i = 0; i < 100; i++)
	{
		expected = 0;
		if (!pg_atomic_compare_exchange_u64(&var, &expected, 1))
			break;
	}
	if (i == 100)
		elog(ERROR, "atomic_compare_exchange_u64() never succeeded");
	if (pg_atomic_read_u64(&var) != 1)
		elog(ERROR, "atomic_compare_exchange_u64() didn't set value properly");

	pg_atomic_write_u64(&var, 0);

	/* try setting flagbits */
	if (pg_atomic_fetch_or_u64(&var, 1) & 1)
		elog(ERROR, "pg_atomic_fetch_or_u64() #1 wrong");

	if (!(pg_atomic_fetch_or_u64(&var, 2) & 1))
		elog(ERROR, "pg_atomic_fetch_or_u64() #2 wrong");

	if (pg_atomic_read_u64(&var) != 3)
		elog(ERROR, "invalid result after pg_atomic_fetch_or_u64()");

	/* try clearing flagbits */
	if ((pg_atomic_fetch_and_u64(&var, ~2) & 3) != 3)
		elog(ERROR, "pg_atomic_fetch_and_u64() #1 wrong");

	if (pg_atomic_fetch_and_u64(&var, ~1) != 1)
		elog(ERROR, "pg_atomic_fetch_and_u64() #2 wrong: is " UINT64_FORMAT,
			 pg_atomic_read_u64(&var));
	/* no bits set anymore */
	if (pg_atomic_fetch_and_u64(&var, ~0) != 0)
		elog(ERROR, "pg_atomic_fetch_and_u64() #3 wrong");
}
#endif   /* PG_HAVE_ATOMIC_U64_SUPPORT */


PG_FUNCTION_INFO_V1(test_atomic_ops);
Datum
test_atomic_ops(PG_FUNCTION_ARGS)
{
	/* ---
	 * Can't run the test under the semaphore emulation, it doesn't handle
	 * checking two edge cases well:
	 * - pg_atomic_unlocked_test_flag() always returns true
	 * - locking a already locked flag blocks
	 * it seems better to not test the semaphore fallback here, than weaken
	 * the checks for the other cases. The semaphore code will be the same
	 * everywhere, whereas the efficient implementations wont.
	 * ---
	 */
#ifndef PG_HAVE_ATOMIC_FLAG_SIMULATION
	test_atomic_flag();
#endif

	test_atomic_uint32();

#ifdef PG_HAVE_ATOMIC_U64_SUPPORT
	test_atomic_uint64();
#endif

	PG_RETURN_BOOL(true);
}