text:
#include "postgres.h"

#include <time.h>

#include "access/nbtree.h"
#include "access/reloptions.h"
#include "access/relscan.h"
#include "commands/progress.h"
#include "miscadmin.h"
#include "utils/array.h"
#include "utils/datum.h"
#include "utils/lsyscache.h"
#include "utils/memutils.h"
#include "utils/rel.h"

typedef struct BTSortArrayContext
{
	FmgrInfo	flinfo;
	Oid			collation;
	bool		reverse;
} BTSortArrayContext;

static Datum _bt_find_extreme_element(IndexScanDesc scan, ScanKey skey,
									  StrategyNumber strat,
									  Datum *elems, int nelems);
static int	_bt_sort_array_elements(IndexScanDesc scan, ScanKey skey,
									bool reverse,
									Datum *elems, int nelems);
static int	_bt_compare_array_elements(const void *a, const void *b, void *arg);
static bool _bt_compare_scankey_args(IndexScanDesc scan, ScanKey op,
									 ScanKey leftarg, ScanKey rightarg,
									 bool *result);
static bool _bt_fix_scankey_strategy(ScanKey skey, int16 *indoption);
static void _bt_mark_scankey_required(ScanKey skey);
static bool _bt_check_rowcompare(ScanKey skey,
								 IndexTuple tuple, int tupnatts, TupleDesc tupdesc,
								 ScanDirection dir, bool *continuescan);
static int	_bt_keep_natts(Relation rel, IndexTuple lastleft,
						   IndexTuple firstright, BTScanInsert itup_key);

/*
 * _bt_mkscankey
 *		Build an insertion scan key that contains comparison data from itup
 *		as well as comparator routines appropriate to the key datatypes.
 *
 *		When itup is a non-pivot tuple, the returned insertion scan key is
 *		suitable for finding a place for it to go on the leaf level.  Pivot
 *		tuples can be used to re-find leaf page with matching high key, but
 *		then caller needs to set scan key's pivotsearch field to true.  This
 *		allows caller to search for a leaf page with a matching high key,
 *		which is usually to the left of the first leaf page a non-pivot match
 *		might appear on.
 *
 *		The result is intended for use with _bt_compare() and _bt_truncate().
 *		Callers that don't need to fill out the insertion scankey arguments
 *		(e.g. they use an ad-hoc comparison routine, or only need a scankey
 *		for _bt_truncate()) can pass a NULL index tuple.  The scankey will
 *		be initialized as if an "all truncated" pivot tuple was passed
 *		instead.
 *
 *		Note that we may occasionally have to share lock the metapage to
 *		determine whether or not the keys in the index are expected to be
 *		unique (i.e. if this is a "heapkeyspace" index).  We assume a
 *		heapkeyspace index when caller passes a NULL tuple, allowing index
 *		build callers to avoid accessing the non-existent metapage.
 */
BTScanInsert
_bt_mkscankey(Relation rel, IndexTuple itup)
{
	BTScanInsert key;
	ScanKey		skey;
	TupleDesc	itupdesc;
	int			indnkeyatts;
	int16	   *indoption;
	int			tupnatts;
	int			i;

	itupdesc = RelationGetDescr(rel);
	indnkeyatts = IndexRelationGetNumberOfKeyAttributes(rel);
	indoption = rel->rd_indoption;
	tupnatts = itup ? BTreeTupleGetNAtts(itup, rel) : 0;

	Assert(tupnatts <= IndexRelationGetNumberOfAttributes(rel));

	/*
	 * We'll execute search using scan key constructed on key columns.
	 * Truncated attributes and non-key attributes are omitted from the final
	 * scan key.
	 */
	key = palloc(offsetof(BTScanInsertData, scankeys) +
				 sizeof(ScanKeyData) * indnkeyatts);
	key->heapkeyspace = itup == NULL || _bt_heapkeyspace(rel);
	key->anynullkeys = false;	/* initial assumption */
	key->nextkey = false;
	key->pivotsearch = false;
	key->keysz = Min(indnkeyatts, tupnatts);
	key->scantid = key->heapkeyspace && itup ?
		BTreeTupleGetHeapTID(itup) : NULL;
	skey = key->scankeys;
	for (i = 0; i < indnkeyatts; i++)
	{
		FmgrInfo   *procinfo;
		Datum		arg;
		bool		null;
		int			flags;

		/*
		 * We can use the cached (default) support procs since no cross-type
		 * comparison can be needed.
		 */
		procinfo = index_getprocinfo(rel, i + 1, BTORDER_PROC);

		/*
		 * Key arguments built from truncated attributes (or when caller
		 * provides no tuple) are defensively represented as NULL values. They
		 * should never be used.
		 */
		if (i < tupnatts)
			arg = index_getattr(itup, i + 1, itupdesc, &null);
		else
		{
			arg = (Datum) 0;
			null = true;
		}
		flags = (null ? SK_ISNULL : 0) | (indoption[i] << SK_BT_INDOPTION_SHIFT);
		ScanKeyEntryInitializeWithInfo(&skey[i],
									   flags,
									   (AttrNumber) (i + 1),
									   InvalidStrategy,
									   InvalidOid,
									   rel->rd_indcollation[i],
									   procinfo,
									   arg);
		/* Record if any key attribute is NULL (or truncated) */
		if (null)
			key->anynullkeys = true;
	}

	return key;
}

/*
 * free a retracement stack made by _bt_search.
 */
void
_bt_freestack(BTStack stack)
{
	BTStack		ostack;

	while (stack != NULL)
	{
		ostack = stack;
		stack = stack->bts_parent;
		pfree(ostack);
	}
}

/*
 *	_bt_preprocess_array_keys() -- Preprocess SK_SEARCHARRAY scan keys
 *
 * If there are any SK_SEARCHARRAY scan keys, deconstruct the array(s) and
 * set up BTArrayKeyInfo info for each one that is an equality-type key.
 * Prepare modified scan keys in so->arrayKeyData, which will hold the current
 * array elements during each primitive indexscan operation.  For inequality
 * array keys, it's sufficient to find the extreme element value and replace
 * the whole array with that scalar value.
 *
 * Note: the reason we need so->arrayKeyData, rather than just scribbling
 * on scan->keyData, is that callers are permitted to call btrescan without
 * supplying a new set of scankey data.
 */
void
_bt_preprocess_array_keys(IndexScanDesc scan)
{
	BTScanOpaque so = (BTScanOpaque) scan->opaque;
	int			numberOfKeys = scan->numberOfKeys;
	int16	   *indoption = scan->indexRelation->rd_indoption;
	int			numArrayKeys;
	ScanKey		cur;
	int			i;
	MemoryContext oldContext;

	/* Quick check to see if there are any array keys */
	numArrayKeys = 0;
	for (i = 0; i < numberOfKeys; i++)
	{
		cur = &scan->keyData[i];
		if (cur->sk_flags & SK_SEARCHARRAY)
		{
			numArrayKeys++;
			Assert(!(cur->sk_flags & (SK_ROW_HEADER | SK_SEARCHNULL | SK_SEARCHNOTNULL)));
			/* If any arrays are null as a whole, we can quit right now. */
			if (cur->sk_flags & SK_ISNULL)
			{
				so->numArrayKeys = -1;
				so->arrayKeyData = NULL;
				return;
			}
		}
	}

	/* Quit if nothing to do. */
	if (numArrayKeys == 0)
	{
		so->numArrayKeys = 0;
		so->arrayKeyData = NULL;
		return;
	}

	/*
	 * Make a scan-lifespan context to hold array-associated data, or reset it
	 * if we already have one from a previous rescan cycle.
	 */
	if (so->arrayContext == NULL)
		so->arrayContext = AllocSetContextCreate(CurrentMemoryContext,
												 "BTree array context",
												 ALLOCSET_SMALL_SIZES);
	else
		MemoryContextReset(so->arrayContext);

	oldContext = MemoryContextSwitchTo(so->arrayContext);

	/* Create modifiable copy of scan->keyData in the workspace context */
	so->arrayKeyData = (ScanKey) palloc(scan->numberOfKeys * sizeof(ScanKeyData));
	memcpy(so->arrayKeyData,
		   scan->keyData,
		   scan->numberOfKeys * sizeof(ScanKeyData));

	/* Allocate space for per-array data in the workspace context */
	so->arrayKeys = (BTArrayKeyInfo *) palloc0(numArrayKeys * sizeof(BTArrayKeyInfo));

	/* Now process each array key */
	numArrayKeys = 0;
	for (i = 0; i < numberOfKeys; i++)
	{
		ArrayType  *arrayval;
		int16		elmlen;
		bool		elmbyval;
		char		elmalign;
		int			num_elems;
		Datum	   *elem_values;
		bool	   *elem_nulls;
		int			num_nonnulls;
		int			j;

		cur = &so->arrayKeyData[i];
		if (!(cur->sk_flags & SK_SEARCHARRAY))
			continue;

		/*
		 * First, deconstruct the array into elements.  Anything allocated
		 * here (including a possibly detoasted array value) is in the
		 * workspace context.
		 */
		arrayval = DatumGetArrayTypeP(cur->sk_argument);
		/* We could cache this data, but not clear it's worth it */
		get_typlenbyvalalign(ARR_ELEMTYPE(arrayval),
							 &elmlen, &elmbyval, &elmalign);
		deconstruct_array(arrayval,
						  ARR_ELEMTYPE(arrayval),
						  elmlen, elmbyval, elmalign,
						  &elem_values, &elem_nulls, &num_elems);

		/*
		 * Compress out any null elements.  We can ignore them since we assume
		 * all btree operators are strict.
		 */
		num_nonnulls = 0;
		for (j = 0; j < num_elems; j++)
		{
			if (!elem_nulls[j])
				elem_values[num_nonnulls++] = elem_values[j];
		}

		/* We could pfree(elem_nulls) now, but not worth the cycles */

		/* If there's no non-nulls, the scan qual is unsatisfiable */
		if (num_nonnulls == 0)
		{
			numArrayKeys = -1;
			break;
		}

		/*
		 * If the comparison operator is not equality, then the array qual
		 * degenerates to a simple comparison against the smallest or largest
		 * non-null array element, as appropriate.
		 */
		switch (cur->sk_strategy)
		{
			case BTLessStrategyNumber:
			case BTLessEqualStrategyNumber:
				cur->sk_argument =
					_bt_find_extreme_element(scan, cur,
											 BTGreaterStrategyNumber,
											 elem_values, num_nonnulls);
				continue;
			case BTEqualStrategyNumber:
				/* proceed with rest of loop */
				break;
			case BTGreaterEqualStrategyNumber:
			case BTGreaterStrategyNumber:
				cur->sk_argument =
					_bt_find_extreme_element(scan, cur,
											 BTLessStrategyNumber,
											 elem_values, num_nonnulls);
				continue;
			default:
				elog(ERROR, "unrecognized StrategyNumber: %d",
					 (int) cur->sk_strategy);
				break;
		}

		/*
		 * Sort the non-null elements and eliminate any duplicates.  We must
		 * sort in the same ordering used by the index column, so that the
		 * successive primitive indexscans produce data in index order.
		 */
		num_elems = _bt_sort_array_elements(scan, cur,
											(indoption[cur->sk_attno - 1] & INDOPTION_DESC) != 0,
											elem_values, num_nonnulls);

		/*
		 * And set up the BTArrayKeyInfo data.
		 */
		so->arrayKeys[numArrayKeys].scan_key = i;
		so->arrayKeys[numArrayKeys].num_elems = num_elems;
		so->arrayKeys[numArrayKeys].elem_values = elem_values;
		numArrayKeys++;
	}

	so->numArrayKeys = numArrayKeys;

	MemoryContextSwitchTo(oldContext);
}

/*
 * _bt_find_extreme_element() -- get least or greatest array element
 *
 * scan and skey identify the index column, whose opfamily determines the
 * comparison semantics.  strat should be BTLessStrategyNumber to get the
 * least element, or BTGreaterStrategyNumber to get the greatest.
 */
static Datum
_bt_find_extreme_element(IndexScanDesc scan, ScanKey skey,
						 StrategyNumber strat,
						 Datum *elems, int nelems)
{
	Relation	rel = scan->indexRelation;
	Oid			elemtype,
				cmp_op;
	RegProcedure cmp_proc;
	FmgrInfo	flinfo;
	Datum		result;
	int			i;

	/*
	 * Determine the nominal datatype of the array elements.  We have to
	 * support the convention that sk_subtype == InvalidOid means the opclass
	 * input type; this is a hack to simplify life for ScanKeyInit().
	 */
	elemtype = skey->sk_subtype;
	if (elemtype == InvalidOid)
		elemtype = rel->rd_opcintype[skey->sk_attno - 1];

	/*
	 * Look up the appropriate comparison operator in the opfamily.
	 *
	 * Note: it's possible that this would fail, if the opfamily is
	 * incomplete, but it seems quite unlikely that an opfamily would omit
	 * non-cross-type comparison operators for any datatype that it supports
	 * at all.
	 */
	cmp_op = get_opfamily_member(rel->rd_opfamily[skey->sk_attno - 1],
								 elemtype,
								 elemtype,
								 strat);
	if (!OidIsValid(cmp_op))
		elog(ERROR, "missing operator %d(%u,%u) in opfamily %u",
			 strat, elemtype, elemtype,
			 rel->rd_opfamily[skey->sk_attno - 1]);
	cmp_proc = get_opcode(cmp_op);
	if (!RegProcedureIsValid(cmp_proc))
		elog(ERROR, "missing oprcode for operator %u", cmp_op);

	fmgr_info(cmp_proc, &flinfo);

	Assert(nelems > 0);
	result = elems[0];
	for (i = 1; i < nelems; i++)
	{
		if (DatumGetBool(FunctionCall2Coll(&flinfo,
										   skey->sk_collation,
										   elems[i],
										   result)))
			result = elems[i];
	}

	return result;
}

/*
 * _bt_sort_array_elements() -- sort and de-dup array elements
 *
 * The array elements are sorted in-place, and the new number of elements
 * after duplicate removal is returned.
 *
 * scan and skey identify the index column, whose opfamily determines the
 * comparison semantics.  If reverse is true, we sort in descending order.
 */
static int
_bt_sort_array_elements(IndexScanDesc scan, ScanKey skey,
						bool reverse,
						Datum *elems, int nelems)
{
	Relation	rel = scan->indexRelation;
	Oid			elemtype;
	RegProcedure cmp_proc;
	BTSortArrayContext cxt;
	int			last_non_dup;
	int			i;

	if (nelems <= 1)
		return nelems;			/* no work to do */

	/*
	 * Determine the nominal datatype of the array elements.  We have to
	 * support the convention that sk_subtype == InvalidOid means the opclass
	 * input type; this is a hack to simplify life for ScanKeyInit().
	 */
	elemtype = skey->sk_subtype;
	if (elemtype == InvalidOid)
		elemtype = rel->rd_opcintype[skey->sk_attno - 1];

	/*
	 * Look up the appropriate comparison function in the opfamily.
	 *
	 * Note: it's possible that this would fail, if the opfamily is
	 * incomplete, but it seems quite unlikely that an opfamily would omit
	 * non-cross-type support functions for any datatype that it supports at
	 * all.
	 */
	cmp_proc = get_opfamily_proc(rel->rd_opfamily[skey->sk_attno - 1],
								 elemtype,
								 elemtype,
								 BTORDER_PROC);
	if (!RegProcedureIsValid(cmp_proc))
		elog(ERROR, "missing support function %d(%u,%u) in opfamily %u",
			 BTORDER_PROC, elemtype, elemtype,
			 rel->rd_opfamily[skey->sk_attno - 1]);

	/* Sort the array elements */
	fmgr_info(cmp_proc, &cxt.flinfo);
	cxt.collation = skey->sk_collation;
	cxt.reverse = reverse;
	qsort_arg((void *) elems, nelems, sizeof(Datum),
			  _bt_compare_array_elements, (void *) &cxt);

	/* Now scan the sorted elements and remove duplicates */
	last_non_dup = 0;
	for (i = 1; i < nelems; i++)
	{
		int32		compare;

		compare = DatumGetInt32(FunctionCall2Coll(&cxt.flinfo,
												  cxt.collation,
												  elems[last_non_dup],
												  elems[i]));
		if (compare != 0)
			elems[++last_non_dup] = elems[i];
	}

	return last_non_dup + 1;
}

/*
 * qsort_arg comparator for sorting array elements
 */
static int
_bt_compare_array_elements(const void *a, const void *b, void *arg)
{
	Datum		da = *((const Datum *) a);
	Datum		db = *((const Datum *) b);
	BTSortArrayContext *cxt = (BTSortArrayContext *) arg;
	int32		compare;

	compare = DatumGetInt32(FunctionCall2Coll(&cxt->flinfo,
											  cxt->collation,
											  da, db));
	if (cxt->reverse)
		INVERT_COMPARE_RESULT(compare);
	return compare;
}

/*
 * _bt_start_array_keys() -- Initialize array keys at start of a scan
 *
 * Set up the cur_elem counters and fill in the first sk_argument value for
 * each array scankey.  We can't do this until we know the scan direction.
 */
void
_bt_start_array_keys(IndexScanDesc scan, ScanDirection dir)
{
	BTScanOpaque so = (BTScanOpaque) scan->opaque;
	int			i;

	for (i = 0; i < so->numArrayKeys; i++)
	{
		BTArrayKeyInfo *curArrayKey = &so->arrayKeys[i];
		ScanKey		skey = &so->arrayKeyData[curArrayKey->scan_key];

		Assert(curArrayKey->num_elems > 0);
		if (ScanDirectionIsBackward(dir))
			curArrayKey->cur_elem = curArrayKey->num_elems - 1;
		else
			curArrayKey->cur_elem = 0;
		skey->sk_argument = curArrayKey->elem_values[curArrayKey->cur_elem];
	}
}

/*
 * _bt_advance_array_keys() -- Advance to next set of array elements
 *
 * Returns true if there is another set of values to consider, false if not.
 * On true result, the scankeys are initialized with the next set of values.
 */
bool
_bt_advance_array_keys(IndexScanDesc scan, ScanDirection dir)
{
	BTScanOpaque so = (BTScanOpaque) scan->opaque;
	bool		found = false;
	int			i;

	/*
	 * We must advance the last array key most quickly, since it will
	 * correspond to the lowest-order index column among the available
	 * qualifications. This is necessary to ensure correct ordering of output
	 * when there are multiple array keys.
	 */
	for (i = so->numArrayKeys - 1; i >= 0; i--)
	{
		BTArrayKeyInfo *curArrayKey = &so->arrayKeys[i];
		ScanKey		skey = &so->arrayKeyData[curArrayKey->scan_key];
		int			cur_elem = curArrayKey->cur_elem;
		int			num_elems = curArrayKey->num_elems;

		if (ScanDirectionIsBackward(dir))
		{
			if (--cur_elem < 0)
			{
				cur_elem = num_elems - 1;
				found = false;	/* need to advance next array key */
			}
			else
				found = true;
		}
		else
		{
			if (++cur_elem >= num_elems)
			{
				cur_elem = 0;
				found = false;	/* need to advance next array key */
			}
			else
				found = true;
		}

		curArrayKey->cur_elem = cur_elem;
		skey->sk_argument = curArrayKey->elem_values[cur_elem];
		if (found)
			break;
	}

	/* advance parallel scan */
	if (scan->parallel_scan != NULL)
		_bt_parallel_advance_array_keys(scan);

	return found;
}

/*
 * _bt_mark_array_keys() -- Handle array keys during btmarkpos
 *
 * Save the current state of the array keys as the "mark" position.
 */
void
_bt_mark_array_keys(IndexScanDesc scan)
{
	BTScanOpaque so = (BTScanOpaque) scan->opaque;
	int			i;

	for (i = 0; i < so->numArrayKeys; i++)
	{
		BTArrayKeyInfo *curArrayKey = &so->arrayKeys[i];

		curArrayKey->mark_elem = curArrayKey->cur_elem;
	}
}

/*
 * _bt_restore_array_keys() -- Handle array keys during btrestrpos
 *
 * Restore the array keys to where they were when the mark was set.
 */
void
_bt_restore_array_keys(IndexScanDesc scan)
{
	BTScanOpaque so = (BTScanOpaque) scan->opaque;
	bool		changed = false;
	int			i;

	/* Restore each array key to its position when the mark was set */
	for (i = 0; i < so->numArrayKeys; i++)
	{
		BTArrayKeyInfo *curArrayKey = &so->arrayKeys[i];
		ScanKey		skey = &so->arrayKeyData[curArrayKey->scan_key];
		int			mark_elem = curArrayKey->mark_elem;

		if (curArrayKey->cur_elem != mark_elem)
		{
			curArrayKey->cur_elem = mark_elem;
			skey->sk_argument = curArrayKey->elem_values[mark_elem];
			changed = true;
		}
	}

	/*
	 * If we changed any keys, we must redo _bt_preprocess_keys.  That might
	 * sound like overkill, but in cases with multiple keys per index column
	 * it seems necessary to do the full set of pushups.
	 */
	if (changed)
	{
		_bt_preprocess_keys(scan);
		/* The mark should have been set on a consistent set of keys... */
		Assert(so->qual_ok);
	}
}

/*
 *	_bt_preprocess_keys() -- Preprocess scan keys
 *
 * The given search-type keys (in scan->keyData[] or so->arrayKeyData[])
 * are copied to so->keyData[] with possible transformation.
 * scan->numberOfKeys is the number of input keys, so->numberOfKeys gets
 * the number of output keys (possibly less, never greater).
 *
 * The output keys are marked with additional sk_flag bits beyond the
 * system-standard bits supplied by the caller.  The DESC and NULLS_FIRST
 * indoption bits for the relevant index attribute are copied into the flags.
 * Also, for a DESC column, we commute (flip) all the sk_strategy numbers
 * so that the index sorts in the desired direction.
 *
 * One key purpose of this routine is to discover which scan keys must be
 * satisfied to continue the scan.  It also attempts to eliminate redundant
 * keys and detect contradictory keys.  (If the index opfamily provides
 * incomplete sets of cross-type operators, we may fail to detect redundant
 * or contradictory keys, but we can survive that.)
 *
 * The output keys must be sorted by index attribute.  Presently we expect
 * (but verify) that the input keys are already so sorted --- this is done
 * by match_clauses_to_index() in indxpath.c.  Some reordering of the keys
 * within each attribute may be done as a byproduct of the processing here,
 * but no other code depends on that.
 *
 * The output keys are marked with flags SK_BT_REQFWD and/or SK_BT_REQBKWD
 * if they must be satisfied in order to continue the scan forward or backward
 * respectively.  _bt_checkkeys uses these flags.  For example, if the quals
 * are "x = 1 AND y < 4 AND z < 5", then _bt_checkkeys will reject a tuple
 * (1,2,7), but we must continue the scan in case there are tuples (1,3,z).
 * But once we reach tuples like (1,4,z) we can stop scanning because no
 * later tuples could match.  This is reflected by marking the x and y keys,
 * but not the z key, with SK_BT_REQFWD.  In general, the keys for leading
 * attributes with "=" keys are marked both SK_BT_REQFWD and SK_BT_REQBKWD.
 * For the first attribute without an "=" key, any "<" and "<=" keys are
 * marked SK_BT_REQFWD while any ">" and ">=" keys are marked SK_BT_REQBKWD.
 * This can be seen to be correct by considering the above example.  Note
 * in particular that if there are no keys for a given attribute, the keys for
 * subsequent attributes can never be required; for instance "WHERE y = 4"
 * requires a full-index scan.
 *
 * If possible, redundant keys are eliminated: we keep only the tightest
 * >/>= bound and the tightest </<= bound, and if there's an = key then
 * that's the only one returned.  (So, we return either a single = key,
 * or one or two boundary-condition keys for each attr.)  However, if we
 * cannot compare two keys for lack of a suitable cross-type operator,
 * we cannot eliminate either.  If there are two such keys of the same
 * operator strategy, the second one is just pushed into the output array
 * without further processing here.  We may also emit both >/>= or both
 * </<= keys if we can't compare them.  The logic about required keys still
 * works if we don't eliminate redundant keys.
 *
 * Note that one reason we need direction-sensitive required-key flags is
 * precisely that we may not be able to eliminate redundant keys.  Suppose
 * we have "x > 4::int AND x > 10::bigint", and we are unable to determine
 * which key is more restrictive for lack of a suitable cross-type operator.
 * _bt_first will arbitrarily pick one of the keys to do the initial
 * positioning with.  If it picks x > 4, then the x > 10 condition will fail
 * until we reach index entries > 10; but we can't stop the scan just because
 * x > 10 is failing.  On the other hand, if we are scanning backwards, then
 * failure of either key is indeed enough to stop the scan.  (In general, when
 * inequality keys are present, the initial-positioning code only promises to
 * position before the first possible match, not exactly at the first match,
 * for a forward scan; or after the last match for a backward scan.)
 *
 * As a byproduct of this work, we can detect contradictory quals such
 * as "x = 1 AND x > 2".  If we see that, we return so->qual_ok = false,
 * indicating the scan need not be run at all since no tuples can match.
 * (In this case we do not bother completing the output key array!)
 * Again, missing cross-type operators might cause us to fail to prove the
 * quals contradictory when they really are, but the scan will work correctly.
 *
 * Row comparison keys are currently also treated without any smarts:
 * we just transfer them into the preprocessed array without any
 * editorialization.  We can treat them the same as an ordinary inequality
 * comparison on the row's first index column, for the purposes of the logic
 * about required keys.
 *
 * Note: the reason we have to copy the preprocessed scan keys into private
 * storage is that we are modifying the array based on comparisons of the
 * key argument values, which could change on a rescan or after moving to
 * new elements of array keys.  Therefore we can't overwrite the source data.
 */
void
_bt_preprocess_keys(IndexScanDesc scan)
{
	BTScanOpaque so = (BTScanOpaque) scan->opaque;
	int			numberOfKeys = scan->numberOfKeys;
	int16	   *indoption = scan->indexRelation->rd_indoption;
	int			new_numberOfKeys;
	int			numberOfEqualCols;
	ScanKey		inkeys;
	ScanKey		outkeys;
	ScanKey		cur;
	ScanKey		xform[BTMaxStrategyNumber];
	bool		test_result;
	int			i,
				j;
	AttrNumber	attno;

	/* initialize result variables */
	so->qual_ok = true;
	so->numberOfKeys = 0;

	if (numberOfKeys < 1)
		return;					/* done if qual-less scan */

	/*
	 * Read so->arrayKeyData if array keys are present, else scan->keyData
	 */
	if (so->arrayKeyData != NULL)
		inkeys = so->arrayKeyData;
	else
		inkeys = scan->keyData;

	outkeys = so->keyData;
	cur = &inkeys[0];
	/* we check that input keys are correctly ordered */
	if (cur->sk_attno < 1)
		elog(ERROR, "btree index keys must be ordered by attribute");

	/* We can short-circuit most of the work if there's just one key */
	if (numberOfKeys == 1)
	{
		/* Apply indoption to scankey (might change sk_strategy!) */
		if (!_bt_fix_scankey_strategy(cur, indoption))
			so->qual_ok = false;
		memcpy(outkeys, cur, sizeof(ScanKeyData));
		so->numberOfKeys = 1;
		/* We can mark the qual as required if it's for first index col */
		if (cur->sk_attno == 1)
			_bt_mark_scankey_required(outkeys);
		return;
	}

	/*
	 * Otherwise, do the full set of pushups.
	 */
	new_numberOfKeys = 0;
	numberOfEqualCols = 0;

	/*
	 * Initialize for processing of keys for attr 1.
	 *
	 * xform[i] points to the currently best scan key of strategy type i+1; it
	 * is NULL if we haven't yet found such a key for this attr.
	 */
	attno = 1;
	memset(xform, 0, sizeof(xform));

	/*
	 * Loop iterates from 0 to numberOfKeys inclusive; we use the last pass to
	 * handle after-last-key processing.  Actual exit from the loop is at the
	 * "break" statement below.
	 */
	for (i = 0;; cur++, i++)
	{
		if (i < numberOfKeys)
		{
			/* Apply indoption to scankey (might change sk_strategy!) */
			if (!_bt_fix_scankey_strategy(cur, indoption))
			{
				/* NULL can't be matched, so give up */
				so->qual_ok = false;
				return;
			}
		}

		/*
		 * If we are at the end of the keys for a particular attr, finish up
		 * processing and emit the cleaned-up keys.
		 */
		if (i == numberOfKeys || cur->sk_attno != attno)
		{
			int			priorNumberOfEqualCols = numberOfEqualCols;

			/* check input keys are correctly ordered */
			if (i < numberOfKeys && cur->sk_attno < attno)
				elog(ERROR, "btree index keys must be ordered by attribute");

			/*
			 * If = has been specified, all other keys can be eliminated as
			 * redundant.  If we have a case like key = 1 AND key > 2, we can
			 * set qual_ok to false and abandon further processing.
			 *
			 * We also have to deal with the case of "key IS NULL", which is
			 * unsatisfiable in combination with any other index condition. By
			 * the time we get here, that's been classified as an equality
			 * check, and we've rejected any combination of it with a regular
			 * equality condition; but not with other types of conditions.
			 */
			if (xform[BTEqualStrategyNumber - 1])
			{
				ScanKey		eq = xform[BTEqualStrategyNumber - 1];

				for (j = BTMaxStrategyNumber; --j >= 0;)
				{
					ScanKey		chk = xform[j];

					if (!chk || j == (BTEqualStrategyNumber - 1))
						continue;

					if (eq->sk_flags & SK_SEARCHNULL)
					{
						/* IS NULL is contradictory to anything else */
						so->qual_ok = false;
						return;
					}

					if (_bt_compare_scankey_args(scan, chk, eq, chk,
												 &test_result))
					{
						if (!test_result)
						{
							/* keys proven mutually contradictory */
							so->qual_ok = false;
							return;
						}
						/* else discard the redundant non-equality key */
						xform[j] = NULL;
					}
					/* else, cannot determine redundancy, keep both keys */
				}
				/* track number of attrs for which we have "=" keys */
				numberOfEqualCols++;
			}

			/* try to keep only one of <, <= */
			if (xform[BTLessStrategyNumber - 1]
				&& xform[BTLessEqualStrategyNumber - 1])
			{
				ScanKey		lt = xform[BTLessStrategyNumber - 1];
				ScanKey		le = xform[BTLessEqualStrategyNumber - 1];

				if (_bt_compare_scankey_args(scan, le, lt, le,
											 &test_result))
				{
					if (test_result)
						xform[BTLessEqualStrategyNumber - 1] = NULL;
					else
						xform[BTLessStrategyNumber - 1] = NULL;
				}
			}

			/* try to keep only one of >, >= */
			if (xform[BTGreaterStrategyNumber - 1]
				&& xform[BTGreaterEqualStrategyNumber - 1])
			{
				ScanKey		gt = xform[BTGreaterStrategyNumber - 1];
				ScanKey		ge = xform[BTGreaterEqualStrategyNumber - 1];

				if (_bt_compare_scankey_args(scan, ge, gt, ge,
											 &test_result))
				{
					if (test_result)
						xform[BTGreaterEqualStrategyNumber - 1] = NULL;
					else
						xform[BTGreaterStrategyNumber - 1] = NULL;
				}
			}

			/*
			 * Emit the cleaned-up keys into the outkeys[] array, and then
			 * mark them if they are required.  They are required (possibly
			 * only in one direction) if all attrs before this one had "=".
			 */
			for (j = BTMaxStrategyNumber; --j >= 0;)
			{
				if (xform[j])
				{
					ScanKey		outkey = &outkeys[new_numberOfKeys++];

					memcpy(outkey, xform[j], sizeof(ScanKeyData));
					if (priorNumberOfEqualCols == attno - 1)
						_bt_mark_scankey_required(outkey);
				}
			}

			/*
			 * Exit loop here if done.
			 */
			if (i == numberOfKeys)
				break;

			/* Re-initialize for new attno */
			attno = cur->sk_attno;
			memset(xform, 0, sizeof(xform));
		}

		/* check strategy this key's operator corresponds to */
		j = cur->sk_strategy - 1;

		/* if row comparison, push it directly to the output array */
		if (cur->sk_flags & SK_ROW_HEADER)
		{
			ScanKey		outkey = &outkeys[new_numberOfKeys++];

			memcpy(outkey, cur, sizeof(ScanKeyData));
			if (numberOfEqualCols == attno - 1)
				_bt_mark_scankey_required(outkey);

			/*
			 * We don't support RowCompare using equality; such a qual would
			 * mess up the numberOfEqualCols tracking.
			 */
			Assert(j != (BTEqualStrategyNumber - 1));
			continue;
		}

		/* have we seen one of these before? */
		if (xform[j] == NULL)
		{
			/* nope, so remember this scankey */
			xform[j] = cur;
		}
		else
		{
			/* yup, keep only the more restrictive key */
			if (_bt_compare_scankey_args(scan, cur, cur, xform[j],
										 &test_result))
			{
				if (test_result)
					xform[j] = cur;
				else if (j == (BTEqualStrategyNumber - 1))
				{
					/* key == a && key == b, but a != b */
					so->qual_ok = false;
					return;
				}
				/* else old key is more restrictive, keep it */
			}
			else
			{
				/*
				 * We can't determine which key is more restrictive.  Keep the
				 * previous one in xform[j] and push this one directly to the
				 * output array.
				 */
				ScanKey		outkey = &outkeys[new_numberOfKeys++];

				memcpy(outkey, cur, sizeof(ScanKeyData));
				if (numberOfEqualCols == attno - 1)
					_bt_mark_scankey_required(outkey);
			}
		}
	}

	so->numberOfKeys = new_numberOfKeys;
}

/*
 * Compare two scankey values using a specified operator.
 *
 * The test we want to perform is logically "leftarg op rightarg", where
 * leftarg and rightarg are the sk_argument values in those ScanKeys, and
 * the comparison operator is the one in the op ScanKey.  However, in
 * cross-data-type situations we may need to look up the correct operator in
 * the index's opfamily: it is the one having amopstrategy = op->sk_strategy
 * and amoplefttype/amoprighttype equal to the two argument datatypes.
 *
 * If the opfamily doesn't supply a complete set of cross-type operators we
 * may not be able to make the comparison.  If we can make the comparison
 * we store the operator result in *result and return true.  We return false
 * if the comparison could not be made.
 *
 * Note: op always points at the same ScanKey as either leftarg or rightarg.
 * Since we don't scribble on the scankeys, this aliasing should cause no
 * trouble.
 *
 * Note: this routine needs to be insensitive to any DESC option applied
 * to the index column.  For example, "x < 4" is a tighter constraint than
 * "x < 5" regardless of which way the index is sorted.
 */
static bool
_bt_compare_scankey_args(IndexScanDesc scan, ScanKey op,
						 ScanKey leftarg, ScanKey rightarg,
						 bool *result)
{
	Relation	rel = scan->indexRelation;
	Oid			lefttype,
				righttype,
				optype,
				opcintype,
				cmp_op;
	StrategyNumber strat;

	/*
	 * First, deal with cases where one or both args are NULL.  This should
	 * only happen when the scankeys represent IS NULL/NOT NULL conditions.
	 */
	if ((leftarg->sk_flags | rightarg->sk_flags) & SK_ISNULL)
	{
		bool		leftnull,
					rightnull;

		if (leftarg->sk_flags & SK_ISNULL)
		{
			Assert(leftarg->sk_flags & (SK_SEARCHNULL | SK_SEARCHNOTNULL));
			leftnull = true;
		}
		else
			leftnull = false;
		if (rightarg->sk_flags & SK_ISNULL)
		{
			Assert(rightarg->sk_flags & (SK_SEARCHNULL | SK_SEARCHNOTNULL));
			rightnull = true;
		}
		else
			rightnull = false;

		/*
		 * We treat NULL as either greater than or less than all other values.
		 * Since true > false, the tests below work correctly for NULLS LAST
		 * logic.  If the index is NULLS FIRST, we need to flip the strategy.
		 */
		strat = op->sk_strategy;
		if (op->sk_flags & SK_BT_NULLS_FIRST)
			strat = BTCommuteStrategyNumber(strat);

		switch (strat)
		{
			case BTLessStrategyNumber:
				*result = (leftnull < rightnull);
				break;
			case BTLessEqualStrategyNumber:
				*result = (leftnull <= rightnull);
				break;
			case BTEqualStrategyNumber:
				*result = (leftnull == rightnull);
				break;
			case BTGreaterEqualStrategyNumber:
				*result = (leftnull >= rightnull);
				break;
			case BTGreaterStrategyNumber:
				*result = (leftnull > rightnull);
				break;
			default:
				elog(ERROR, "unrecognized StrategyNumber: %d", (int) strat);
				*result = false;	/* keep compiler quiet */
				break;
		}
		return true;
	}

	/*
	 * The opfamily we need to worry about is identified by the index column.
	 */
	Assert(leftarg->sk_attno == rightarg->sk_attno);

	opcintype = rel->rd_opcintype[leftarg->sk_attno - 1];

	/*
	 * Determine the actual datatypes of the ScanKey arguments.  We have to
	 * support the convention that sk_subtype == InvalidOid means the opclass
	 * input type; this is a hack to simplify life for ScanKeyInit().
	 */
	lefttype = leftarg->sk_subtype;
	if (lefttype == InvalidOid)
		lefttype = opcintype;
	righttype = rightarg->sk_subtype;
	if (righttype == InvalidOid)
		righttype = opcintype;
	optype = op->sk_subtype;
	if (optype == InvalidOid)
		optype = opcintype;

	/*
	 * If leftarg and rightarg match the types expected for the "op" scankey,
	 * we can use its already-looked-up comparison function.
	 */
	if (lefttype == opcintype && righttype == optype)
	{
		*result = DatumGetBool(FunctionCall2Coll(&op->sk_func,
												 op->sk_collation,
												 leftarg->sk_argument,
												 rightarg->sk_argument));
		return true;
	}

	/*
	 * Otherwise, we need to go to the syscache to find the appropriate
	 * operator.  (This cannot result in infinite recursion, since no
	 * indexscan initiated by syscache lookup will use cross-data-type
	 * operators.)
	 *
	 * If the sk_strategy was flipped by _bt_fix_scankey_strategy, we have to
	 * un-flip it to get the correct opfamily member.
	 */
	strat = op->sk_strategy;
	if (op->sk_flags & SK_BT_DESC)
		strat = BTCommuteStrategyNumber(strat);

	cmp_op = get_opfamily_member(rel->rd_opfamily[leftarg->sk_attno - 1],
								 lefttype,
								 righttype,
								 strat);
	if (OidIsValid(cmp_op))
	{
		RegProcedure cmp_proc = get_opcode(cmp_op);

		if (RegProcedureIsValid(cmp_proc))
		{
			*result = DatumGetBool(OidFunctionCall2Coll(cmp_proc,
														op->sk_collation,
														leftarg->sk_argument,
														rightarg->sk_argument));
			return true;
		}
	}

	/* Can't make the comparison */
	*result = false;			/* suppress compiler warnings */
	return false;
}

/*
 * Adjust a scankey's strategy and flags setting as needed for indoptions.
 *
 * We copy the appropriate indoption value into the scankey sk_flags
 * (shifting to avoid clobbering system-defined flag bits).  Also, if
 * the DESC option is set, commute (flip) the operator strategy number.
 *
 * A secondary purpose is to check for IS NULL/NOT NULL scankeys and set up
 * the strategy field correctly for them.
 *
 * Lastly, for ordinary scankeys (not IS NULL/NOT NULL), we check for a
 * NULL comparison value.  Since all btree operators are assumed strict,
 * a NULL means that the qual cannot be satisfied.  We return true if the
 * comparison value isn't NULL, or false if the scan should be abandoned.
 *
 * This function is applied to the *input* scankey structure; therefore
 * on a rescan we will be looking at already-processed scankeys.  Hence
 * we have to be careful not to re-commute the strategy if we already did it.
 * It's a bit ugly to modify the caller's copy of the scankey but in practice
 * there shouldn't be any problem, since the index's indoptions are certainly
 * not going to change while the scankey survives.
 */
static bool
_bt_fix_scankey_strategy(ScanKey skey, int16 *indoption)
{
	int			addflags;

	addflags = indoption[skey->sk_attno - 1] << SK_BT_INDOPTION_SHIFT;

	/*
	 * We treat all btree operators as strict (even if they're not so marked
	 * in pg_proc). This means that it is impossible for an operator condition
	 * with a NULL comparison constant to succeed, and we can reject it right
	 * away.
	 *
	 * However, we now also support "x IS NULL" clauses as search conditions,
	 * so in that case keep going. The planner has not filled in any
	 * particular strategy in this case, so set it to BTEqualStrategyNumber
	 * --- we can treat IS NULL as an equality operator for purposes of search
	 * strategy.
	 *
	 * Likewise, "x IS NOT NULL" is supported.  We treat that as either "less
	 * than NULL" in a NULLS LAST index, or "greater than NULL" in a NULLS
	 * FIRST index.
	 *
	 * Note: someday we might have to fill in sk_collation from the index
	 * column's collation.  At the moment this is a non-issue because we'll
	 * never actually call the comparison operator on a NULL.
	 */
	if (skey->sk_flags & SK_ISNULL)
	{
		/* SK_ISNULL shouldn't be set in a row header scankey */
		Assert(!(skey->sk_flags & SK_ROW_HEADER));

		/* Set indoption flags in scankey (might be done already) */
		skey->sk_flags |= addflags;

		/* Set correct strategy for IS NULL or NOT NULL search */
		if (skey->sk_flags & SK_SEARCHNULL)
		{
			skey->sk_strategy = BTEqualStrategyNumber;
			skey->sk_subtype = InvalidOid;
			skey->sk_collation = InvalidOid;
		}
		else if (skey->sk_flags & SK_SEARCHNOTNULL)
		{
			if (skey->sk_flags & SK_BT_NULLS_FIRST)
				skey->sk_strategy = BTGreaterStrategyNumber;
			else
				skey->sk_strategy = BTLessStrategyNumber;
			skey->sk_subtype = InvalidOid;
			skey->sk_collation = InvalidOid;
		}
		else
		{
			/* regular qual, so it cannot be satisfied */
			return false;
		}

		/* Needn't do the rest */
		return true;
	}

	/* Adjust strategy for DESC, if we didn't already */
	if ((addflags & SK_BT_DESC) && !(skey->sk_flags & SK_BT_DESC))
		skey->sk_strategy = BTCommuteStrategyNumber(skey->sk_strategy);
	skey->sk_flags |= addflags;

	/* If it's a row header, fix row member flags and strategies similarly */
	if (skey->sk_flags & SK_ROW_HEADER)
	{
		ScanKey		subkey = (ScanKey) DatumGetPointer(skey->sk_argument);

		for (;;)
		{
			Assert(subkey->sk_flags & SK_ROW_MEMBER);
			addflags = indoption[subkey->sk_attno - 1] << SK_BT_INDOPTION_SHIFT;
			if ((addflags & SK_BT_DESC) && !(subkey->sk_flags & SK_BT_DESC))
				subkey->sk_strategy = BTCommuteStrategyNumber(subkey->sk_strategy);
			subkey->sk_flags |= addflags;
			if (subkey->sk_flags & SK_ROW_END)
				break;
			subkey++;
		}
	}

	return true;
}

/*
 * Mark a scankey as "required to continue the scan".
 *
 * Depending on the operator type, the key may be required for both scan
 * directions or just one.  Also, if the key is a row comparison header,
 * we have to mark its first subsidiary ScanKey as required.  (Subsequent
 * subsidiary ScanKeys are normally for lower-order columns, and thus
 * cannot be required, since they're after the first non-equality scankey.)
 *
 * Note: when we set required-key flag bits in a subsidiary scankey, we are
 * scribbling on a data structure belonging to the index AM's caller, not on
 * our private copy.  This should be OK because the marking will not change
 * from scan to scan within a query, and so we'd just re-mark the same way
 * anyway on a rescan.  Something to keep an eye on though.
 */
static void
_bt_mark_scankey_required(ScanKey skey)
{
	int			addflags;

	switch (skey->sk_strategy)
	{
		case BTLessStrategyNumber:
		case BTLessEqualStrategyNumber:
			addflags = SK_BT_REQFWD;
			break;
		case BTEqualStrategyNumber:
			addflags = SK_BT_REQFWD | SK_BT_REQBKWD;
			break;
		case BTGreaterEqualStrategyNumber:
		case BTGreaterStrategyNumber:
			addflags = SK_BT_REQBKWD;
			break;
		default:
			elog(ERROR, "unrecognized StrategyNumber: %d",
				 (int) skey->sk_strategy);
			addflags = 0;		/* keep compiler quiet */
			break;
	}

	skey->sk_flags |= addflags;

	if (skey->sk_flags & SK_ROW_HEADER)
	{
		ScanKey		subkey = (ScanKey) DatumGetPointer(skey->sk_argument);

		/* First subkey should be same column/operator as the header */
		Assert(subkey->sk_flags & SK_ROW_MEMBER);
		Assert(subkey->sk_attno == skey->sk_attno);
		Assert(subkey->sk_strategy == skey->sk_strategy);
		subkey->sk_flags |= addflags;
	}
}

/*
 * Test whether an indextuple satisfies all the scankey conditions.
 *
 * Return true if so, false if not.  If the tuple fails to pass the qual,
 * we also determine whether there's any need to continue the scan beyond
 * this tuple, and set *continuescan accordingly.  See comments for
 * _bt_preprocess_keys(), above, about how this is done.
 *
 * Forward scan callers can pass a high key tuple in the hopes of having
 * us set *continuescan to false, and avoiding an unnecessary visit to
 * the page to the right.
 *
 * scan: index scan descriptor (containing a search-type scankey)
 * tuple: index tuple to test
 * tupnatts: number of attributes in tupnatts (high key may be truncated)
 * dir: direction we are scanning in
 * continuescan: output parameter (will be set correctly in all cases)
 */
bool
_bt_checkkeys(IndexScanDesc scan, IndexTuple tuple, int tupnatts,
			  ScanDirection dir, bool *continuescan)
{
	TupleDesc	tupdesc;
	BTScanOpaque so;
	int			keysz;
	int			ikey;
	ScanKey		key;

	Assert(BTreeTupleGetNAtts(tuple, scan->indexRelation) == tupnatts);

	*continuescan = true;		/* default assumption */

	tupdesc = RelationGetDescr(scan->indexRelation);
	so = (BTScanOpaque) scan->opaque;
	keysz = so->numberOfKeys;

	for (key = so->keyData, ikey = 0; ikey < keysz; key++, ikey++)
	{
		Datum		datum;
		bool		isNull;
		Datum		test;

		if (key->sk_attno > tupnatts)
		{
			/*
			 * This attribute is truncated (must be high key).  The value for
			 * this attribute in the first non-pivot tuple on the page to the
			 * right could be any possible value.  Assume that truncated
			 * attribute passes the qual.
			 */
			Assert(ScanDirectionIsForward(dir));
			continue;
		}

		/* row-comparison keys need special processing */
		if (key->sk_flags & SK_ROW_HEADER)
		{
			if (_bt_check_rowcompare(key, tuple, tupnatts, tupdesc, dir,
									 continuescan))
				continue;
			return false;
		}

		datum = index_getattr(tuple,
							  key->sk_attno,
							  tupdesc,
							  &isNull);

		if (key->sk_flags & SK_ISNULL)
		{
			/* Handle IS NULL/NOT NULL tests */
			if (key->sk_flags & SK_SEARCHNULL)
			{
				if (isNull)
					continue;	/* tuple satisfies this qual */
			}
			else
			{
				Assert(key->sk_flags & SK_SEARCHNOTNULL);
				if (!isNull)
					continue;	/* tuple satisfies this qual */
			}

			/*
			 * Tuple fails this qual.  If it's a required qual for the current
			 * scan direction, then we can conclude no further tuples will
			 * pass, either.
			 */
			if ((key->sk_flags & SK_BT_REQFWD) &&
				ScanDirectionIsForward(dir))
				*continuescan = false;
			else if ((key->sk_flags & SK_BT_REQBKWD) &&
					 ScanDirectionIsBackward(dir))
				*continuescan = false;

			/*
			 * In any case, this indextuple doesn't match the qual.
			 */
			return false;
		}

		if (isNull)
		{
			if (key->sk_flags & SK_BT_NULLS_FIRST)
			{
				/*
				 * Since NULLs are sorted before non-NULLs, we know we have
				 * reached the lower limit of the range of values for this
				 * index attr.  On a backward scan, we can stop if this qual
				 * is one of the "must match" subset.  We can stop regardless
				 * of whether the qual is > or <, so long as it's required,
				 * because it's not possible for any future tuples to pass. On
				 * a forward scan, however, we must keep going, because we may
				 * have initially positioned to the start of the index.
				 */
				if ((key->sk_flags & (SK_BT_REQFWD | SK_BT_REQBKWD)) &&
					ScanDirectionIsBackward(dir))
					*continuescan = false;
			}
			else
			{
				/*
				 * Since NULLs are sorted after non-NULLs, we know we have
				 * reached the upper limit of the range of values for this
				 * index attr.  On a forward scan, we can stop if this qual is
				 * one of the "must match" subset.  We can stop regardless of
				 * whether the qual is > or <, so long as it's required,
				 * because it's not possible for any future tuples to pass. On
				 * a backward scan, however, we must keep going, because we
				 * may have initially positioned to the end of the index.
				 */
				if ((key->sk_flags & (SK_BT_REQFWD | SK_BT_REQBKWD)) &&
					ScanDirectionIsForward(dir))
					*continuescan = false;
			}

			/*
			 * In any case, this indextuple doesn't match the qual.
			 */
			return false;
		}

		test = FunctionCall2Coll(&key->sk_func, key->sk_collation,
								 datum, key->sk_argument);

		if (!DatumGetBool(test))
		{
			/*
			 * Tuple fails this qual.  If it's a required qual for the current
			 * scan direction, then we can conclude no further tuples will
			 * pass, either.
			 *
			 * Note: because we stop the scan as soon as any required equality
			 * qual fails, it is critical that equality quals be used for the
			 * initial positioning in _bt_first() when they are available. See
			 * comments in _bt_first().
			 */
			if ((key->sk_flags & SK_BT_REQFWD) &&
				ScanDirectionIsForward(dir))
				*continuescan = false;
			else if ((key->sk_flags & SK_BT_REQBKWD) &&
					 ScanDirectionIsBackward(dir))
				*continuescan = false;

			/*
			 * In any case, this indextuple doesn't match the qual.
			 */
			return false;
		}
	}

	/* If we get here, the tuple passes all index quals. */
	return true;
}

/*
 * Test whether an indextuple satisfies a row-comparison scan condition.
 *
 * Return true if so, false if not.  If not, also clear *continuescan if
 * it's not possible for any future tuples in the current scan direction
 * to pass the qual.
 *
 * This is a subroutine for _bt_checkkeys, which see for more info.
 */
static bool
_bt_check_rowcompare(ScanKey skey, IndexTuple tuple, int tupnatts,
					 TupleDesc tupdesc, ScanDirection dir, bool *continuescan)
{
	ScanKey		subkey = (ScanKey) DatumGetPointer(skey->sk_argument);
	int32		cmpresult = 0;
	bool		result;

	/* First subkey should be same as the header says */
	Assert(subkey->sk_attno == skey->sk_attno);

	/* Loop over columns of the row condition */
	for (;;)
	{
		Datum		datum;
		bool		isNull;

		Assert(subkey->sk_flags & SK_ROW_MEMBER);

		if (subkey->sk_attno > tupnatts)
		{
			/*
			 * This attribute is truncated (must be high key).  The value for
			 * this attribute in the first non-pivot tuple on the page to the
			 * right could be any possible value.  Assume that truncated
			 * attribute passes the qual.
			 */
			Assert(ScanDirectionIsForward(dir));
			cmpresult = 0;
			if (subkey->sk_flags & SK_ROW_END)
				break;
			subkey++;
			continue;
		}

		datum = index_getattr(tuple,
							  subkey->sk_attno,
							  tupdesc,
							  &isNull);

		if (isNull)
		{
			if (subkey->sk_flags & SK_BT_NULLS_FIRST)
			{
				/*
				 * Since NULLs are sorted before non-NULLs, we know we have
				 * reached the lower limit of the range of values for this
				 * index attr.  On a backward scan, we can stop if this qual
				 * is one of the "must match" subset.  We can stop regardless
				 * of whether the qual is > or <, so long as it's required,
				 * because it's not possible for any future tuples to pass. On
				 * a forward scan, however, we must keep going, because we may
				 * have initially positioned to the start of the index.
				 */
				if ((subkey->sk_flags & (SK_BT_REQFWD | SK_BT_REQBKWD)) &&
					ScanDirectionIsBackward(dir))
					*continuescan = false;
			}
			else
			{
				/*
				 * Since NULLs are sorted after non-NULLs, we know we have
				 * reached the upper limit of the range of values for this
				 * index attr.  On a forward scan, we can stop if this qual is
				 * one of the "must match" subset.  We can stop regardless of
				 * whether the qual is > or <, so long as it's required,
				 * because it's not possible for any future tuples to pass. On
				 * a backward scan, however, we must keep going, because we
				 * may have initially positioned to the end of the index.
				 */
				if ((subkey->sk_flags & (SK_BT_REQFWD | SK_BT_REQBKWD)) &&
					ScanDirectionIsForward(dir))
					*continuescan = false;
			}

			/*
			 * In any case, this indextuple doesn't match the qual.
			 */
			return false;
		}

		if (subkey->sk_flags & SK_ISNULL)
		{
			/*
			 * Unlike the simple-scankey case, this isn't a disallowed case.
			 * But it can never match.  If all the earlier row comparison
			 * columns are required for the scan direction, we can stop the
			 * scan, because there can't be another tuple that will succeed.
			 */
			if (subkey != (ScanKey) DatumGetPointer(skey->sk_argument))
				subkey--;
			if ((subkey->sk_flags & SK_BT_REQFWD) &&
				ScanDirectionIsForward(dir))
				*continuescan = false;
			else if ((subkey->sk_flags & SK_BT_REQBKWD) &&
					 ScanDirectionIsBackward(dir))
				*continuescan = false;
			return false;
		}

		/* Perform the test --- three-way comparison not bool operator */
		cmpresult = DatumGetInt32(FunctionCall2Coll(&subkey->sk_func,
													subkey->sk_collation,
													datum,
													subkey->sk_argument));

		if (subkey->sk_flags & SK_BT_DESC)
			INVERT_COMPARE_RESULT(cmpresult);

		/* Done comparing if unequal, else advance to next column */
		if (cmpresult != 0)
			break;

		if (subkey->sk_flags & SK_ROW_END)
			break;
		subkey++;
	}

	/*
	 * At this point cmpresult indicates the overall result of the row
	 * comparison, and subkey points to the deciding column (or the last
	 * column if the result is "=").
	 */
	switch (subkey->sk_strategy)
	{
			/* EQ and NE cases aren't allowed here */
		case BTLessStrategyNumber:
			result = (cmpresult < 0);
			break;
		case BTLessEqualStrategyNumber:
			result = (cmpresult <= 0);
			break;
		case BTGreaterEqualStrategyNumber:
			result = (cmpresult >= 0);
			break;
		case BTGreaterStrategyNumber:
			result = (cmpresult > 0);
			break;
		default:
			elog(ERROR, "unrecognized RowCompareType: %d",
				 (int) subkey->sk_strategy);
			result = 0;			/* keep compiler quiet */
			break;
	}

	if (!result)
	{
		/*
		 * Tuple fails this qual.  If it's a required qual for the current
		 * scan direction, then we can conclude no further tuples will pass,
		 * either.  Note we have to look at the deciding column, not
		 * necessarily the first or last column of the row condition.
		 */
		if ((subkey->sk_flags & SK_BT_REQFWD) &&
			ScanDirectionIsForward(dir))
			*continuescan = false;
		else if ((subkey->sk_flags & SK_BT_REQBKWD) &&
				 ScanDirectionIsBackward(dir))
			*continuescan = false;
	}

	return result;
}

/*
 * _bt_killitems - set LP_DEAD state for items an indexscan caller has
 * told us were killed
 *
 * scan->opaque, referenced locally through so, contains information about the
 * current page and killed tuples thereon (generally, this should only be
 * called if so->numKilled > 0).
 *
 * The caller does not have a lock on the page and may or may not have the
 * page pinned in a buffer.  Note that read-lock is sufficient for setting
 * LP_DEAD status (which is only a hint).
 *
 * We match items by heap TID before assuming they are the right ones to
 * delete.  We cope with cases where items have moved right due to insertions.
 * If an item has moved off the current page due to a split, we'll fail to
 * find it and do nothing (this is not an error case --- we assume the item
 * will eventually get marked in a future indexscan).
 *
 * Note that if we hold a pin on the target page continuously from initially
 * reading the items until applying this function, VACUUM cannot have deleted
 * any items from the page, and so there is no need to search left from the
 * recorded offset.  (This observation also guarantees that the item is still
 * the right one to delete, which might otherwise be questionable since heap
 * TIDs can get recycled.)	This holds true even if the page has been modified
 * by inserts and page splits, so there is no need to consult the LSN.
 *
 * If the pin was released after reading the page, then we re-read it.  If it
 * has been modified since we read it (as determined by the LSN), we dare not
 * flag any entries because it is possible that the old entry was vacuumed
 * away and the TID was re-used by a completely different heap tuple.
 */
void
_bt_killitems(IndexScanDesc scan)
{
	BTScanOpaque so = (BTScanOpaque) scan->opaque;
	Page		page;
	BTPageOpaque opaque;
	OffsetNumber minoff;
	OffsetNumber maxoff;
	int			i;
	int			numKilled = so->numKilled;
	bool		killedsomething = false;

	Assert(BTScanPosIsValid(so->currPos));

	/*
	 * Always reset the scan state, so we don't look for same items on other
	 * pages.
	 */
	so->numKilled = 0;

	if (BTScanPosIsPinned(so->currPos))
	{
		/*
		 * We have held the pin on this page since we read the index tuples,
		 * so all we need to do is lock it.  The pin will have prevented
		 * re-use of any TID on the page, so there is no need to check the
		 * LSN.
		 */
		LockBuffer(so->currPos.buf, BT_READ);

		page = BufferGetPage(so->currPos.buf);
	}
	else
	{
		Buffer		buf;

		/* Attempt to re-read the buffer, getting pin and lock. */
		buf = _bt_getbuf(scan->indexRelation, so->currPos.currPage, BT_READ);

		/* It might not exist anymore; in which case we can't hint it. */
		if (!BufferIsValid(buf))
			return;

		page = BufferGetPage(buf);
		if (BufferGetLSNAtomic(buf) == so->currPos.lsn)
			so->currPos.buf = buf;
		else
		{
			/* Modified while not pinned means hinting is not safe. */
			_bt_relbuf(scan->indexRelation, buf);
			return;
		}
	}

	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
	minoff = P_FIRSTDATAKEY(opaque);
	maxoff = PageGetMaxOffsetNumber(page);

	for (i = 0; i < numKilled; i++)
	{
		int			itemIndex = so->killedItems[i];
		BTScanPosItem *kitem = &so->currPos.items[itemIndex];
		OffsetNumber offnum = kitem->indexOffset;

		Assert(itemIndex >= so->currPos.firstItem &&
			   itemIndex <= so->currPos.lastItem);
		if (offnum < minoff)
			continue;			/* pure paranoia */
		while (offnum <= maxoff)
		{
			ItemId		iid = PageGetItemId(page, offnum);
			IndexTuple	ituple = (IndexTuple) PageGetItem(page, iid);

			if (ItemPointerEquals(&ituple->t_tid, &kitem->heapTid))
			{
				/* found the item */
				ItemIdMarkDead(iid);
				killedsomething = true;
				break;			/* out of inner search loop */
			}
			offnum = OffsetNumberNext(offnum);
		}
	}

	/*
	 * Since this can be redone later if needed, mark as dirty hint.
	 *
	 * Whenever we mark anything LP_DEAD, we also set the page's
	 * BTP_HAS_GARBAGE flag, which is likewise just a hint.
	 */
	if (killedsomething)
	{
		opaque->btpo_flags |= BTP_HAS_GARBAGE;
		MarkBufferDirtyHint(so->currPos.buf, true);
	}

	LockBuffer(so->currPos.buf, BUFFER_LOCK_UNLOCK);
}

/*
 * The following routines manage a shared-memory area in which we track
 * assignment of "vacuum cycle IDs" to currently-active btree vacuuming
 * operations.  There is a single counter which increments each time we
 * start a vacuum to assign it a cycle ID.  Since multiple vacuums could
 * be active concurrently, we have to track the cycle ID for each active
 * vacuum; this requires at most MaxBackends entries (usually far fewer).
 * We assume at most one vacuum can be active for a given index.
 *
 * Access to the shared memory area is controlled by BtreeVacuumLock.
 * In principle we could use a separate lmgr locktag for each index,
 * but a single LWLock is much cheaper, and given the short time that
 * the lock is ever held, the concurrency hit should be minimal.
 */

typedef struct BTOneVacInfo
{
	LockRelId	relid;			/* global identifier of an index */
	BTCycleId	cycleid;		/* cycle ID for its active VACUUM */
} BTOneVacInfo;

typedef struct BTVacInfo
{
	BTCycleId	cycle_ctr;		/* cycle ID most recently assigned */
	int			num_vacuums;	/* number of currently active VACUUMs */
	int			max_vacuums;	/* allocated length of vacuums[] array */
	BTOneVacInfo vacuums[FLEXIBLE_ARRAY_MEMBER];
} BTVacInfo;

static BTVacInfo *btvacinfo;

/*
 * _bt_vacuum_cycleid --- get the active vacuum cycle ID for an index,
 *		or zero if there is no active VACUUM
 *
 * Note: for correct interlocking, the caller must already hold pin and
 * exclusive lock on each buffer it will store the cycle ID into.  This
 * ensures that even if a VACUUM starts immediately afterwards, it cannot
 * process those pages until the page split is complete.
 */
BTCycleId
_bt_vacuum_cycleid(Relation rel)
{
	BTCycleId	result = 0;
	int			i;

	/* Share lock is enough since this is a read-only operation */
	LWLockAcquire(BtreeVacuumLock, LW_SHARED);

	for (i = 0; i < btvacinfo->num_vacuums; i++)
	{
		BTOneVacInfo *vac = &btvacinfo->vacuums[i];

		if (vac->relid.relId == rel->rd_lockInfo.lockRelId.relId &&
			vac->relid.dbId == rel->rd_lockInfo.lockRelId.dbId)
		{
			result = vac->cycleid;
			break;
		}
	}

	LWLockRelease(BtreeVacuumLock);
	return result;
}

/*
 * _bt_start_vacuum --- assign a cycle ID to a just-starting VACUUM operation
 *
 * Note: the caller must guarantee that it will eventually call
 * _bt_end_vacuum, else we'll permanently leak an array slot.  To ensure
 * that this happens even in elog(FATAL) scenarios, the appropriate coding
 * is not just a PG_TRY, but
 *		PG_ENSURE_ERROR_CLEANUP(_bt_end_vacuum_callback, PointerGetDatum(rel))
 */
BTCycleId
_bt_start_vacuum(Relation rel)
{
	BTCycleId	result;
	int			i;
	BTOneVacInfo *vac;

	LWLockAcquire(BtreeVacuumLock, LW_EXCLUSIVE);

	/*
	 * Assign the next cycle ID, being careful to avoid zero as well as the
	 * reserved high values.
	 */
	result = ++(btvacinfo->cycle_ctr);
	if (result == 0 || result > MAX_BT_CYCLE_ID)
		result = btvacinfo->cycle_ctr = 1;

	/* Let's just make sure there's no entry already for this index */
	for (i = 0; i < btvacinfo->num_vacuums; i++)
	{
		vac = &btvacinfo->vacuums[i];
		if (vac->relid.relId == rel->rd_lockInfo.lockRelId.relId &&
			vac->relid.dbId == rel->rd_lockInfo.lockRelId.dbId)
		{
			/*
			 * Unlike most places in the backend, we have to explicitly
			 * release our LWLock before throwing an error.  This is because
			 * we expect _bt_end_vacuum() to be called before transaction
			 * abort cleanup can run to release LWLocks.
			 */
			LWLockRelease(BtreeVacuumLock);
			elog(ERROR, "multiple active vacuums for index \"%s\"",
				 RelationGetRelationName(rel));
		}
	}

	/* OK, add an entry */
	if (btvacinfo->num_vacuums >= btvacinfo->max_vacuums)
	{
		LWLockRelease(BtreeVacuumLock);
		elog(ERROR, "out of btvacinfo slots");
	}
	vac = &btvacinfo->vacuums[btvacinfo->num_vacuums];
	vac->relid = rel->rd_lockInfo.lockRelId;
	vac->cycleid = result;
	btvacinfo->num_vacuums++;

	LWLockRelease(BtreeVacuumLock);
	return result;
}

/*
 * _bt_end_vacuum --- mark a btree VACUUM operation as done
 *
 * Note: this is deliberately coded not to complain if no entry is found;
 * this allows the caller to put PG_TRY around the start_vacuum operation.
 */
void
_bt_end_vacuum(Relation rel)
{
	int			i;

	LWLockAcquire(BtreeVacuumLock, LW_EXCLUSIVE);

	/* Find the array entry */
	for (i = 0; i < btvacinfo->num_vacuums; i++)
	{
		BTOneVacInfo *vac = &btvacinfo->vacuums[i];

		if (vac->relid.relId == rel->rd_lockInfo.lockRelId.relId &&
			vac->relid.dbId == rel->rd_lockInfo.lockRelId.dbId)
		{
			/* Remove it by shifting down the last entry */
			*vac = btvacinfo->vacuums[btvacinfo->num_vacuums - 1];
			btvacinfo->num_vacuums--;
			break;
		}
	}

	LWLockRelease(BtreeVacuumLock);
}

/*
 * _bt_end_vacuum wrapped as an on_shmem_exit callback function
 */
void
_bt_end_vacuum_callback(int code pg_attribute_unused(), Datum arg)
{
	_bt_end_vacuum((Relation) DatumGetPointer(arg));
}

/*
 * BTreeShmemSize --- report amount of shared memory space needed
 */
Size
BTreeShmemSize(void)
{
	Size		size;

	size = offsetof(BTVacInfo, vacuums);
	size = add_size(size, mul_size(MaxBackends, sizeof(BTOneVacInfo)));
	return size;
}

/*
 * BTreeShmemInit --- initialize this module's shared memory
 */
void
BTreeShmemInit(void)
{
	bool		found;

	btvacinfo = (BTVacInfo *) ShmemInitStruct("BTree Vacuum State",
											  BTreeShmemSize(),
											  &found);

	if (!IsUnderPostmaster)
	{
		/* Initialize shared memory area */
		Assert(!found);

		/*
		 * It doesn't really matter what the cycle counter starts at, but
		 * having it always start the same doesn't seem good.  Seed with
		 * low-order bits of time() instead.
		 */
		btvacinfo->cycle_ctr = (BTCycleId) time(NULL);

		btvacinfo->num_vacuums = 0;
		btvacinfo->max_vacuums = MaxBackends;
	}
	else
		Assert(found);
}

bytea *
btoptions(Datum reloptions, bool validate)
{
	return default_reloptions(reloptions, validate, RELOPT_KIND_BTREE);
}

/*
 *	btproperty() -- Check boolean properties of indexes.
 *
 * This is optional, but handling AMPROP_RETURNABLE here saves opening the rel
 * to call btcanreturn.
 */
bool
btproperty(Oid index_oid, int attno,
		   IndexAMProperty prop, const char *propname,
		   bool *res, bool *isnull)
{
	switch (prop)
	{
		case AMPROP_RETURNABLE:
			/* answer only for columns, not AM or whole index */
			if (attno == 0)
				return false;
			/* otherwise, btree can always return data */
			*res = true;
			return true;

		default:
			return false;		/* punt to generic code */
	}
}

/*
 *	btbuildphasename() -- Return name of index build phase.
 */
char *
btbuildphasename(int64 phasenum)
{
	switch (phasenum)
	{
		case PROGRESS_CREATEIDX_SUBPHASE_INITIALIZE:
			return "initializing";
		case PROGRESS_BTREE_PHASE_INDEXBUILD_TABLESCAN:
			return "scanning table";
		case PROGRESS_BTREE_PHASE_PERFORMSORT_1:
			return "sorting live tuples";
		case PROGRESS_BTREE_PHASE_PERFORMSORT_2:
			return "sorting dead tuples";
		case PROGRESS_BTREE_PHASE_LEAF_LOAD:
			return "loading tuples in tree";
		default:
			return NULL;
	}
}

/*
 *	_bt_truncate() -- create tuple without unneeded suffix attributes.
 *
 * Returns truncated pivot index tuple allocated in caller's memory context,
 * with key attributes copied from caller's firstright argument.  If rel is
 * an INCLUDE index, non-key attributes will definitely be truncated away,
 * since they're not part of the key space.  More aggressive suffix
 * truncation can take place when it's clear that the returned tuple does not
 * need one or more suffix key attributes.  We only need to keep firstright
 * attributes up to and including the first non-lastleft-equal attribute.
 * Caller's insertion scankey is used to compare the tuples; the scankey's
 * argument values are not considered here.
 *
 * Sometimes this routine will return a new pivot tuple that takes up more
 * space than firstright, because a new heap TID attribute had to be added to
 * distinguish lastleft from firstright.  This should only happen when the
 * caller is in the process of splitting a leaf page that has many logical
 * duplicates, where it's unavoidable.
 *
 * Note that returned tuple's t_tid offset will hold the number of attributes
 * present, so the original item pointer offset is not represented.  Caller
 * should only change truncated tuple's downlink.  Note also that truncated
 * key attributes are treated as containing "minus infinity" values by
 * _bt_compare().
 *
 * In the worst case (when a heap TID is appended) the size of the returned
 * tuple is the size of the first right tuple plus an additional MAXALIGN()'d
 * item pointer.  This guarantee is important, since callers need to stay
 * under the 1/3 of a page restriction on tuple size.  If this routine is ever
 * taught to truncate within an attribute/datum, it will need to avoid
 * returning an enlarged tuple to caller when truncation + TOAST compression
 * ends up enlarging the final datum.
 */
IndexTuple
_bt_truncate(Relation rel, IndexTuple lastleft, IndexTuple firstright,
			 BTScanInsert itup_key)
{
	TupleDesc	itupdesc = RelationGetDescr(rel);
	int16		natts = IndexRelationGetNumberOfAttributes(rel);
	int16		nkeyatts = IndexRelationGetNumberOfKeyAttributes(rel);
	int			keepnatts;
	IndexTuple	pivot;
	ItemPointer pivotheaptid;
	Size		newsize;

	/*
	 * We should only ever truncate leaf index tuples.  It's never okay to
	 * truncate a second time.
	 */
	Assert(BTreeTupleGetNAtts(lastleft, rel) == natts);
	Assert(BTreeTupleGetNAtts(firstright, rel) == natts);

	/* Determine how many attributes must be kept in truncated tuple */
	keepnatts = _bt_keep_natts(rel, lastleft, firstright, itup_key);

#ifdef DEBUG_NO_TRUNCATE
	/* Force truncation to be ineffective for testing purposes */
	keepnatts = nkeyatts + 1;
#endif

	if (keepnatts <= natts)
	{
		IndexTuple	tidpivot;

		pivot = index_truncate_tuple(itupdesc, firstright, keepnatts);

		/*
		 * If there is a distinguishing key attribute within new pivot tuple,
		 * there is no need to add an explicit heap TID attribute
		 */
		if (keepnatts <= nkeyatts)
		{
			BTreeTupleSetNAtts(pivot, keepnatts);
			return pivot;
		}

		/*
		 * Only truncation of non-key attributes was possible, since key
		 * attributes are all equal.  It's necessary to add a heap TID
		 * attribute to the new pivot tuple.
		 */
		Assert(natts != nkeyatts);
		newsize = IndexTupleSize(pivot) + MAXALIGN(sizeof(ItemPointerData));
		tidpivot = palloc0(newsize);
		memcpy(tidpivot, pivot, IndexTupleSize(pivot));
		/* cannot leak memory here */
		pfree(pivot);
		pivot = tidpivot;
	}
	else
	{
		/*
		 * No truncation was possible, since key attributes are all equal.
		 * It's necessary to add a heap TID attribute to the new pivot tuple.
		 */
		Assert(natts == nkeyatts);
		newsize = IndexTupleSize(firstright) + MAXALIGN(sizeof(ItemPointerData));
		pivot = palloc0(newsize);
		memcpy(pivot, firstright, IndexTupleSize(firstright));
	}

	/*
	 * We have to use heap TID as a unique-ifier in the new pivot tuple, since
	 * no non-TID key attribute in the right item readily distinguishes the
	 * right side of the split from the left side.  Use enlarged space that
	 * holds a copy of first right tuple; place a heap TID value within the
	 * extra space that remains at the end.
	 *
	 * nbtree conceptualizes this case as an inability to truncate away any
	 * key attribute.  We must use an alternative representation of heap TID
	 * within pivots because heap TID is only treated as an attribute within
	 * nbtree (e.g., there is no pg_attribute entry).
	 */
	Assert(itup_key->heapkeyspace);
	pivot->t_info &= ~INDEX_SIZE_MASK;
	pivot->t_info |= newsize;

	/*
	 * Lehman & Yao use lastleft as the leaf high key in all cases, but don't
	 * consider suffix truncation.  It seems like a good idea to follow that
	 * example in cases where no truncation takes place -- use lastleft's heap
	 * TID.  (This is also the closest value to negative infinity that's
	 * legally usable.)
	 */
	pivotheaptid = (ItemPointer) ((char *) pivot + newsize -
								  sizeof(ItemPointerData));
	ItemPointerCopy(&lastleft->t_tid, pivotheaptid);

	/*
	 * Lehman and Yao require that the downlink to the right page, which is to
	 * be inserted into the parent page in the second phase of a page split be
	 * a strict lower bound on items on the right page, and a non-strict upper
	 * bound for items on the left page.  Assert that heap TIDs follow these
	 * invariants, since a heap TID value is apparently needed as a
	 * tiebreaker.
	 */
#ifndef DEBUG_NO_TRUNCATE
	Assert(ItemPointerCompare(&lastleft->t_tid, &firstright->t_tid) < 0);
	Assert(ItemPointerCompare(pivotheaptid, &lastleft->t_tid) >= 0);
	Assert(ItemPointerCompare(pivotheaptid, &firstright->t_tid) < 0);
#else

	/*
	 * Those invariants aren't guaranteed to hold for lastleft + firstright
	 * heap TID attribute values when they're considered here only because
	 * DEBUG_NO_TRUNCATE is defined (a heap TID is probably not actually
	 * needed as a tiebreaker).  DEBUG_NO_TRUNCATE must therefore use a heap
	 * TID value that always works as a strict lower bound for items to the
	 * right.  In particular, it must avoid using firstright's leading key
	 * attribute values along with lastleft's heap TID value when lastleft's
	 * TID happens to be greater than firstright's TID.
	 */
	ItemPointerCopy(&firstright->t_tid, pivotheaptid);

	/*
	 * Pivot heap TID should never be fully equal to firstright.  Note that
	 * the pivot heap TID will still end up equal to lastleft's heap TID when
	 * that's the only usable value.
	 */
	ItemPointerSetOffsetNumber(pivotheaptid,
							   OffsetNumberPrev(ItemPointerGetOffsetNumber(pivotheaptid)));
	Assert(ItemPointerCompare(pivotheaptid, &firstright->t_tid) < 0);
#endif

	BTreeTupleSetNAtts(pivot, nkeyatts);
	BTreeTupleSetAltHeapTID(pivot);

	return pivot;
}

/*
 * _bt_keep_natts - how many key attributes to keep when truncating.
 *
 * Caller provides two tuples that enclose a split point.  Caller's insertion
 * scankey is used to compare the tuples; the scankey's argument values are
 * not considered here.
 *
 * This can return a number of attributes that is one greater than the
 * number of key attributes for the index relation.  This indicates that the
 * caller must use a heap TID as a unique-ifier in new pivot tuple.
 */
static int
_bt_keep_natts(Relation rel, IndexTuple lastleft, IndexTuple firstright,
			   BTScanInsert itup_key)
{
	int			nkeyatts = IndexRelationGetNumberOfKeyAttributes(rel);
	TupleDesc	itupdesc = RelationGetDescr(rel);
	int			keepnatts;
	ScanKey		scankey;

	/*
	 * Be consistent about the representation of BTREE_VERSION 2/3 tuples
	 * across Postgres versions; don't allow new pivot tuples to have
	 * truncated key attributes there.  _bt_compare() treats truncated key
	 * attributes as having the value minus infinity, which would break
	 * searches within !heapkeyspace indexes.
	 */
	if (!itup_key->heapkeyspace)
	{
		Assert(nkeyatts != IndexRelationGetNumberOfAttributes(rel));
		return nkeyatts;
	}

	scankey = itup_key->scankeys;
	keepnatts = 1;
	for (int attnum = 1; attnum <= nkeyatts; attnum++, scankey++)
	{
		Datum		datum1,
					datum2;
		bool		isNull1,
					isNull2;

		datum1 = index_getattr(lastleft, attnum, itupdesc, &isNull1);
		datum2 = index_getattr(firstright, attnum, itupdesc, &isNull2);

		if (isNull1 != isNull2)
			break;

		if (!isNull1 &&
			DatumGetInt32(FunctionCall2Coll(&scankey->sk_func,
											scankey->sk_collation,
											datum1,
											datum2)) != 0)
			break;

		keepnatts++;
	}

	return keepnatts;
}

/*
 * _bt_keep_natts_fast - fast bitwise variant of _bt_keep_natts.
 *
 * This is exported so that a candidate split point can have its effect on
 * suffix truncation inexpensively evaluated ahead of time when finding a
 * split location.  A naive bitwise approach to datum comparisons is used to
 * save cycles.
 *
 * The approach taken here usually provides the same answer as _bt_keep_natts
 * will (for the same pair of tuples from a heapkeyspace index), since the
 * majority of btree opclasses can never indicate that two datums are equal
 * unless they're bitwise equal (once detoasted).  Similarly, result may
 * differ from the _bt_keep_natts result when either tuple has TOASTed datums,
 * though this is barely possible in practice.
 *
 * These issues must be acceptable to callers, typically because they're only
 * concerned about making suffix truncation as effective as possible without
 * leaving excessive amounts of free space on either side of page split.
 * Callers can rely on the fact that attributes considered equal here are
 * definitely also equal according to _bt_keep_natts.
 */
int
_bt_keep_natts_fast(Relation rel, IndexTuple lastleft, IndexTuple firstright)
{
	TupleDesc	itupdesc = RelationGetDescr(rel);
	int			keysz = IndexRelationGetNumberOfKeyAttributes(rel);
	int			keepnatts;

	keepnatts = 1;
	for (int attnum = 1; attnum <= keysz; attnum++)
	{
		Datum		datum1,
					datum2;
		bool		isNull1,
					isNull2;
		Form_pg_attribute att;

		datum1 = index_getattr(lastleft, attnum, itupdesc, &isNull1);
		datum2 = index_getattr(firstright, attnum, itupdesc, &isNull2);
		att = TupleDescAttr(itupdesc, attnum - 1);

		if (isNull1 != isNull2)
			break;

		if (!isNull1 &&
			!datumIsEqual(datum1, datum2, att->attbyval, att->attlen))
			break;

		keepnatts++;
	}

	return keepnatts;
}

/*
 *  _bt_check_natts() -- Verify tuple has expected number of attributes.
 *
 * Returns value indicating if the expected number of attributes were found
 * for a particular offset on page.  This can be used as a general purpose
 * sanity check.
 *
 * Testing a tuple directly with BTreeTupleGetNAtts() should generally be
 * preferred to calling here.  That's usually more convenient, and is always
 * more explicit.  Call here instead when offnum's tuple may be a negative
 * infinity tuple that uses the pre-v11 on-disk representation, or when a low
 * context check is appropriate.  This routine is as strict as possible about
 * what is expected on each version of btree.
 */
bool
_bt_check_natts(Relation rel, bool heapkeyspace, Page page, OffsetNumber offnum)
{
	int16		natts = IndexRelationGetNumberOfAttributes(rel);
	int16		nkeyatts = IndexRelationGetNumberOfKeyAttributes(rel);
	BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page);
	IndexTuple	itup;
	int			tupnatts;

	/*
	 * We cannot reliably test a deleted or half-deleted page, since they have
	 * dummy high keys
	 */
	if (P_IGNORE(opaque))
		return true;

	Assert(offnum >= FirstOffsetNumber &&
		   offnum <= PageGetMaxOffsetNumber(page));

	/*
	 * Mask allocated for number of keys in index tuple must be able to fit
	 * maximum possible number of index attributes
	 */
	StaticAssertStmt(BT_N_KEYS_OFFSET_MASK >= INDEX_MAX_KEYS,
					 "BT_N_KEYS_OFFSET_MASK can't fit INDEX_MAX_KEYS");

	itup = (IndexTuple) PageGetItem(page, PageGetItemId(page, offnum));
	tupnatts = BTreeTupleGetNAtts(itup, rel);

	if (P_ISLEAF(opaque))
	{
		if (offnum >= P_FIRSTDATAKEY(opaque))
		{
			/*
			 * Non-pivot tuples currently never use alternative heap TID
			 * representation -- even those within heapkeyspace indexes
			 */
			if ((itup->t_info & INDEX_ALT_TID_MASK) != 0)
				return false;

			/*
			 * Leaf tuples that are not the page high key (non-pivot tuples)
			 * should never be truncated.  (Note that tupnatts must have been
			 * inferred, rather than coming from an explicit on-disk
			 * representation.)
			 */
			return tupnatts == natts;
		}
		else
		{
			/*
			 * Rightmost page doesn't contain a page high key, so tuple was
			 * checked above as ordinary leaf tuple
			 */
			Assert(!P_RIGHTMOST(opaque));

			/*
			 * !heapkeyspace high key tuple contains only key attributes. Note
			 * that tupnatts will only have been explicitly represented in
			 * !heapkeyspace indexes that happen to have non-key attributes.
			 */
			if (!heapkeyspace)
				return tupnatts == nkeyatts;

			/* Use generic heapkeyspace pivot tuple handling */
		}
	}
	else						/* !P_ISLEAF(opaque) */
	{
		if (offnum == P_FIRSTDATAKEY(opaque))
		{
			/*
			 * The first tuple on any internal page (possibly the first after
			 * its high key) is its negative infinity tuple.  Negative
			 * infinity tuples are always truncated to zero attributes.  They
			 * are a particular kind of pivot tuple.
			 */
			if (heapkeyspace)
				return tupnatts == 0;

			/*
			 * The number of attributes won't be explicitly represented if the
			 * negative infinity tuple was generated during a page split that
			 * occurred with a version of Postgres before v11.  There must be
			 * a problem when there is an explicit representation that is
			 * non-zero, or when there is no explicit representation and the
			 * tuple is evidently not a pre-pg_upgrade tuple.
			 *
			 * Prior to v11, downlinks always had P_HIKEY as their offset. Use
			 * that to decide if the tuple is a pre-v11 tuple.
			 */
			return tupnatts == 0 ||
				((itup->t_info & INDEX_ALT_TID_MASK) == 0 &&
				 ItemPointerGetOffsetNumber(&(itup->t_tid)) == P_HIKEY);
		}
		else
		{
			/*
			 * !heapkeyspace downlink tuple with separator key contains only
			 * key attributes.  Note that tupnatts will only have been
			 * explicitly represented in !heapkeyspace indexes that happen to
			 * have non-key attributes.
			 */
			if (!heapkeyspace)
				return tupnatts == nkeyatts;

			/* Use generic heapkeyspace pivot tuple handling */
		}

	}

	/* Handle heapkeyspace pivot tuples (excluding minus infinity items) */
	Assert(heapkeyspace);

	/*
	 * Explicit representation of the number of attributes is mandatory with
	 * heapkeyspace index pivot tuples, regardless of whether or not there are
	 * non-key attributes.
	 */
	if ((itup->t_info & INDEX_ALT_TID_MASK) == 0)
		return false;

	/*
	 * Heap TID is a tiebreaker key attribute, so it cannot be untruncated
	 * when any other key attribute is truncated
	 */
	if (BTreeTupleGetHeapTID(itup) != NULL && tupnatts != nkeyatts)
		return false;

	/*
	 * Pivot tuple must have at least one untruncated key attribute (minus
	 * infinity pivot tuples are the only exception).  Pivot tuples can never
	 * represent that there is a value present for a key attribute that
	 * exceeds pg_index.indnkeyatts for the index.
	 */
	return tupnatts > 0 && tupnatts <= nkeyatts;
}

/*
 *
 *  _bt_check_third_page() -- check whether tuple fits on a btree page at all.
 *
 * We actually need to be able to fit three items on every page, so restrict
 * any one item to 1/3 the per-page available space.  Note that itemsz should
 * not include the ItemId overhead.
 *
 * It might be useful to apply TOAST methods rather than throw an error here.
 * Using out of line storage would break assumptions made by suffix truncation
 * and by contrib/amcheck, though.
 */
void
_bt_check_third_page(Relation rel, Relation heap, bool needheaptidspace,
					 Page page, IndexTuple newtup)
{
	Size		itemsz;
	BTPageOpaque opaque;

	itemsz = MAXALIGN(IndexTupleSize(newtup));

	/* Double check item size against limit */
	if (itemsz <= BTMaxItemSize(page))
		return;

	/*
	 * Tuple is probably too large to fit on page, but it's possible that the
	 * index uses version 2 or version 3, or that page is an internal page, in
	 * which case a slightly higher limit applies.
	 */
	if (!needheaptidspace && itemsz <= BTMaxItemSizeNoHeapTid(page))
		return;

	/*
	 * Internal page insertions cannot fail here, because that would mean that
	 * an earlier leaf level insertion that should have failed didn't
	 */
	opaque = (BTPageOpaque) PageGetSpecialPointer(page);
	if (!P_ISLEAF(opaque))
		elog(ERROR, "cannot insert oversized tuple of size %zu on internal page of index \"%s\"",
			 itemsz, RelationGetRelationName(rel));

	ereport(ERROR,
			(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
			 errmsg("index row size %zu exceeds btree version %u maximum %zu for index \"%s\"",
					itemsz,
					needheaptidspace ? BTREE_VERSION : BTREE_NOVAC_VERSION,
					needheaptidspace ? BTMaxItemSize(page) :
					BTMaxItemSizeNoHeapTid(page),
					RelationGetRelationName(rel)),
			 errdetail("Index row references tuple (%u,%u) in relation \"%s\".",
					   ItemPointerGetBlockNumber(&newtup->t_tid),
					   ItemPointerGetOffsetNumber(&newtup->t_tid),
					   RelationGetRelationName(heap)),
			 errhint("Values larger than 1/3 of a buffer page cannot be indexed.\n"
					 "Consider a function index of an MD5 hash of the value, "
					 "or use full text indexing."),
			 errtableconstraint(heap, RelationGetRelationName(rel))));
}


text:
import unittest
import macostools
import Carbon.File
import MacOS
import os
import sys
from test import test_support

TESTFN2 = test_support.TESTFN + '2'

class TestMacostools(unittest.TestCase):

    def setUp(self):
        fp = open(test_support.TESTFN, 'w')
        fp.write('hello world\n')
        fp.close()
        rfp = MacOS.openrf(test_support.TESTFN, '*wb')
        rfp.write('goodbye world\n')
        rfp.close()

    def tearDown(self):
        test_support.unlink(test_support.TESTFN)
        test_support.unlink(TESTFN2)

    def compareData(self):
        fp = open(test_support.TESTFN, 'r')
        data1 = fp.read()
        fp.close()
        fp = open(TESTFN2, 'r')
        data2 = fp.read()
        fp.close()
        if data1 != data2:
            return 'Data forks differ'
        rfp = MacOS.openrf(test_support.TESTFN, '*rb')
        data1 = rfp.read(1000)
        rfp.close()
        rfp = MacOS.openrf(TESTFN2, '*rb')
        data2 = rfp.read(1000)
        rfp.close()
        if data1 != data2:
            return 'Resource forks differ'
        return ''

    def test_touched(self):
        # This really only tests that nothing unforeseen happens.
        with test_support.check_warnings(('macostools.touched*',
                                          DeprecationWarning), quiet=True):
            macostools.touched(test_support.TESTFN)

    if sys.maxint < 2**32:
        def test_copy(self):
            test_support.unlink(TESTFN2)
            macostools.copy(test_support.TESTFN, TESTFN2)
            self.assertEqual(self.compareData(), '')

    if sys.maxint < 2**32:
        def test_mkalias(self):
            test_support.unlink(TESTFN2)
            macostools.mkalias(test_support.TESTFN, TESTFN2)
            fss, _, _ = Carbon.File.ResolveAliasFile(TESTFN2, 0)
            self.assertEqual(fss.as_pathname(), os.path.realpath(test_support.TESTFN))

        def test_mkalias_relative(self):
            test_support.unlink(TESTFN2)
            # If the directory doesn't exist, then chances are this is a new
            # install of Python so don't create it since the user might end up
            # running ``sudo make install`` and creating the directory here won't
            # leave it with the proper permissions.
            if not os.path.exists(sys.prefix):
                return
            macostools.mkalias(test_support.TESTFN, TESTFN2, sys.prefix)
            fss, _, _ = Carbon.File.ResolveAliasFile(TESTFN2, 0)
            self.assertEqual(fss.as_pathname(), os.path.realpath(test_support.TESTFN))

def test_main():
    # Skip on wide unicode
    if len(u'\0'.encode('unicode-internal')) == 4:
        raise test_support.TestSkipped("test_macostools is broken in USC4")
    test_support.run_unittest(TestMacostools)

if __name__ == '__main__':
    test_main()

redpajama_set_name: RedPajamaGithub


text:
@interface BCLNonCachingHTTPConnection : NSObject

+(NSData *)sendSynchronousRequest:(NSURLRequest *)request returningResponse:(NSURLResponse **)response error:(NSError **)error;

-(instancetype)initWithURLRequest:(NSURLRequest *)request NS_DESIGNATED_INITIALIZER;
@property(atomic, readonly) NSURLRequest *URLRequest;

-(NSData *)sendSynchronouslyAndReturnResponse:(NSURLResponse **)response error:(NSError **)error;

@end


text:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:showIn="@layout/flavor_item">
    <ImageView
        android:id="@+id/backdrop"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_margin="1dp"
        android:adjustViewBounds="true"

        />
</LinearLayout>


text:
using System;
using Microsoft.VisualStudio.TestTools.UnitTesting;
using TicTacToe.Core;

namespace T3Test.Core
{
    [TestClass]
    public class BoardTests
    {
        [TestMethod]
        public void TestInitialization()
        {
            Board b = new Board();
            Assert.AreEqual(Status.NotStarted,b.CurrentStatus);

            Assert.AreEqual( CellType.Clear,b[0, 0]);
            Assert.AreEqual(CellType.Clear,b[1, 2]);

            b.StartGame(Player.Player1);
            Assert.AreEqual(Status.TurnP1,b.CurrentStatus);

        }

        [TestMethod]
        public void TestAsigning()
        {
            Board b = new Board();
            b.StartGame(Player.Player1);

            b[1, 1] = CellType.Player1;

            Assert.AreEqual( CellType.Player1,b[1, 1]);
            Assert.AreEqual(Status.TurnP2,b.CurrentStatus);
            Assert.AreEqual(1,b.NumCheckedCells);

            Assert.IsTrue(b.IsGameInProgress);
            Assert.IsFalse(b.IsGameEnded);

            try
            {
                b[1, 1] = CellType.Player2;
                Assert.Fail("No exception - overwrite");
            }
            catch (InvalidOperationException )
            {      }

            try
            {
                b[3, 1] = CellType.Player2;
                Assert.Fail("No exception - out of range");
            }
            catch (ArgumentOutOfRangeException )
            {}

            try
            {
                b[2, 1] = CellType.Player1;
                Assert.Fail("No exception - wrong player");
            }
            catch (InvalidOperationException)
            { }

            //cancelling
            b.CancelGame();
            Assert.IsTrue(b.IsGameEnded);
            Assert.IsFalse(b.IsGameInProgress);
            Assert.AreEqual(Status.Cancelled, b.CurrentStatus);
            try
            {
                b[0, 2] = CellType.Player2;
                Assert.Fail("No exception - cancelled game");
            }
            catch (InvalidOperationException)
            {
            }
        }

        [TestMethod]
        public void TestWinning()
        {
            Board b = new Board();
            b.StartGame(Player.Player2);

            Assert.IsTrue(b.IsGameInProgress);
            b[1, 1] = CellType.Player2;
            b[1, 2] = CellType.Player1;
            Assert.IsTrue(b.IsGameInProgress);
            b[0, 0] = CellType.Player2;
            b[0, 2] = CellType.Player1;
            Assert.IsTrue(b.IsGameInProgress);
            Assert.IsFalse(b.IsGameEnded);
            b[2, 2] = CellType.Player2;

            Assert.IsFalse(b.IsGameInProgress);
            Assert.IsTrue(b.IsGameEnded);
            Assert.AreEqual(Status.WonP2, b.CurrentStatus);

            try
            {
                b[2, 0] = CellType.Player1;
                Assert.Fail("No exception- doing moves after winning");
            }
            catch (InvalidOperationException)
            { }
        }

        [TestMethod]
        public void TestTie()
        {
            Board b = new Board();
            b.StartGame(Player.Player2);

            b[0, 0] = CellType.Player2;
            b[0, 1] = CellType.Player1;
            b[0, 2] = CellType.Player2;
            b[1, 1] = CellType.Player1;
            b[1, 0] = CellType.Player2;
            b[2, 0] = CellType.Player1;
            b[1, 2] = CellType.Player2;
            b[2, 2] = CellType.Player1;

            Assert.IsTrue(b.IsGameInProgress);
            b[2, 1] = CellType.Player2;
            Assert.IsTrue(b.IsGameEnded);
            Assert.IsFalse(b.IsGameInProgress);
            Assert.AreEqual(Status.Tie, b.CurrentStatus);

        }

    }
}


text:
package org.netbeans.jpa.modeler.source.generator.adaptor;

import java.util.ServiceLoader;

/**
 *
 * @author Gaurav Gupta
 */
public interface ISourceCodeGeneratorFactory {

    public ISourceCodeGenerator getSourceGenerator(SourceCodeGeneratorType sourceGeneratorFactoryType);

//    public static ISourceCodeGeneratorFactory getInstance() {
//        for (ISourceCodeGeneratorFactory service : ServiceLoader.load(ISourceCodeGeneratorFactory.class)) {
//            return service;
//        }
//        return null;
//    }
}


text:
<?xml version="1.0" encoding="UTF-8"?>
<document xmlns="http://maven.apache.org/XDOC/2.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/XDOC/2.0 http://maven.apache.org/xsd/xdoc-2.0.xsd">

	<properties>
		<title>JAX-RS Server</title>
		<author email="jamesagnew@users.sourceforge.net">James Agnew</author>
	</properties>

				The standard server is implemented using Servlet technology. A module
				exists which implements the server using JAX-RS technology.
				This enables the usage of existing Java EE interceptors and annotations. This module does not provide the full set of features.

				The server currently supports
				Conformance Statements,
				@Read,
				@Search,
				@Create,
				@Update,
				@Delete and
				@Operation.

				The primary intention for this project is to ensure that other web technologies (JAX-RS in this case) can be used together with the base-server functionality.
				An example server can be found in the Git repo here.

			<subsection name="JAX-RS Implementation specifics">

				The set-up of a JAX-RS server goes beyond the scope of this documentation. The implementation of the server follows the same pattern as the standard server. It is required
				to put the correct annotation on the methods in the Resource Providers in order to be able to call them.

				Implementing a JAX-RS Resource Provider requires some JAX-RS annotations. The @Path
				annotation needs to define the resource path. The @Produces annotation
				needs to declare the produced formats. The constructor needs to pass the class of the object explicitely in order to avoid  problems with proxy classes in a Java EE environment.
				It is necessary to extend the abstract class
				AbstractJaxRsResourceProvider.
				<macro name="snippet">
					<param name="id" value="jax-rs-provider-construction" />
					<param name="file" value="examples/src/main/java/example/JaxRsPatientRestProvider.java" />
				</macro>

				Extended Operations require the correct JAX-RS (
				@Path,
				@GET or
				@POST) annotations. The body of the method needs to call the
				method AbstractJaxRsResourceProvider#customOperation
				with the correct parameters. The server will then call the method with corresponding name.
				<macro name="snippet">
					<param name="id" value="jax-rs-provider-operation" />
					<param name="file" value="examples/src/main/java/example/JaxRsPatientRestProvider.java" />
				</macro>

				In order to create the conformance profile, a conformance provider class needs to be deployed which exports the provider's conformance statements.
				These providers need to be returned  as the result of
				the method AbstractJaxRsResourceProvider#getProviders.
				This method is called once, during PostConstruct.
				<macro name="snippet">
					<param name="id" value="jax-rs-conformance" />
					<param name="file" value="examples/src/main/java/example/JaxRsConformanceProvider.java" />
				</macro>

			</subsection>

				A complete example showing how to implement a JAX-RS RESTful server can
				be found in our Git repo here:
				https://github.com/jamesagnew/hapi-fhir/tree/master/hapi-fhir-jaxrsserver-example

</document>


text:
from django.db import migrations, models

class Migration(migrations.Migration):

    dependencies = [("elasticsearch_django", "0003_auto_20160926_2021")]

    operations = [
        migrations.AlterField(
            model_name="searchquery",
            name="hits",
            field=models.JSONField(
                help_text="The list of meta info for each of the query matches returned."
            ),
        ),
        migrations.AlterField(
            model_name="searchquery",
            name="query",
            field=models.JSONField(help_text="The raw Elasticsearch DSL query."),
        ),
    ]


text:
<?php

/**
 * Dawn
 * MVC PHP Framework (5.4+)
 *
 * @description     HttpResponse class. Handle HTTP response (header, cookie).
 * @file            HttpResponse.php
 * @version         1
 * @package         Dawn
 * @author          Patrick Bélanger (patrick.belanger <dot> gmail <dot> com)
 * @licence         Apache 2.0  http://www.apache.org/licenses/LICENSE-2.0
 **/

namespace DawnFramework;

class HttpResponse extends \DawnFramework\StaticView {

    /******************************************************************************************************************
     * COOKIES
     *****************************************************************************************************************/

    public function addCookie($cookie) {
        setcookie(
            isset($cookie['name']) ? $cookie['name'] : $cookie = '',
            isset($cookie['value']) ? $cookie['value'] : $cookie = '',
            isset($cookie['expire']) ? $cookie['expire'] : $cookie = 0,
            isset($cookie['path']) ? $cookie['path'] : null,
            isset($cookie['domain']) ? $cookie['domain'] : null,
            isset($cookie['secure']) ? $cookie['secure'] : false,
            isset($cookie['httpOnly']) ? $cookie['httpOnly'] : true
        );
    }

    /******************************************************************************************************************
     * DECODE / ENCODE
     *****************************************************************************************************************/

    public function decodeUrl($url) {
        return urldecode($url);
    }

    public function encodeUrl($url) {
        return urlencode($url);
    }

    /******************************************************************************************************************
     * HEADER
     *****************************************************************************************************************/

    public function headerSend($raw) {
        if (!headers_sent()) {
            header($raw);
        }
        exit;
    }

    public function headerSetCharacterEncoding($charset = 'utf-8') {
        header('Content-Type: text/html; charset=' . $charset);
        exit;
    }

    public function headersList() {
        return headers_list();
    }

    /******************************************************************************************************************
     * HEADER (REDIRECT/FORWARD)
     *****************************************************************************************************************/

    public function redirect($location) {
        if (!headers_sent()) {
            header('location' . $location);
        }
        exit;
    }

}


text:
<?php

namespace DuckTV\AppBundle\Repository;

/**
 * SlotRepository
 *
 * This class was generated by the Doctrine ORM. Add your own custom
 * repository methods below.
 */
class SlotRepository extends \Doctrine\ORM\EntityRepository
{
}


text:
layout: page
title: Camacho Pink Software Seminar
date: 2016-05-24
author: William Kaiser
tags: weekly links, java
status: published
summary: Proin elementum mi nunc, in fringilla neque rhoncus eget.
banner: images/banner/leisure-03.jpg
booking:
  startDate: 10/23/2018
  endDate: 10/24/2018
  ctyhocn: BHMLSHX
  groupCode: CPSS
published: true
---
Nullam a suscipit nunc. Lorem ipsum dolor sit amet, consectetur adipiscing elit. Mauris sodales arcu purus, nec vehicula odio efficitur at. Phasellus suscipit lorem non viverra molestie. Vivamus ut dolor in erat condimentum facilisis rhoncus id orci. Duis vitae nisl quis leo maximus laoreet. Phasellus lectus tortor, consectetur dictum fringilla bibendum, sagittis non nunc.

* Quisque ac libero eget nulla tempus commodo
* Donec et purus tempor, aliquet tortor id, lacinia nulla
* Morbi tincidunt nisi non magna blandit, ut molestie diam lobortis
* Donec laoreet sem sit amet vehicula gravida
* Cras scelerisque sapien quis sem commodo, bibendum hendrerit mi rutrum.

Nunc non bibendum tellus. Quisque sit amet ante ipsum. Sed convallis dapibus justo sit amet pretium. Donec feugiat eleifend lacinia. Nam aliquet dictum lorem sit amet faucibus. Nam faucibus purus at felis euismod, et vestibulum ligula luctus. Praesent facilisis ipsum sed sapien accumsan faucibus.