1 files changed, 51 insertions, 1 deletions

diff --git a/contrib/btree_gist/btree_cash.c b/contrib/btree_gist/btree_cash.c
index bfda21b058c..7938a70f17a 100644
--- a/contrib/btree_gist/btree_cash.c
+++ b/contrib/btree_gist/btree_cash.c
@@ -18,6 +18,7 @@ PG_FUNCTION_INFO_V1(gbt_cash_compress);
 PG_FUNCTION_INFO_V1(gbt_cash_union);
 PG_FUNCTION_INFO_V1(gbt_cash_picksplit);
 PG_FUNCTION_INFO_V1(gbt_cash_consistent);
+PG_FUNCTION_INFO_V1(gbt_cash_distance);
 PG_FUNCTION_INFO_V1(gbt_cash_penalty);
 PG_FUNCTION_INFO_V1(gbt_cash_same);
 
@@ -25,6 +26,7 @@ Datum		gbt_cash_compress(PG_FUNCTION_ARGS);
 Datum		gbt_cash_union(PG_FUNCTION_ARGS);
 Datum		gbt_cash_picksplit(PG_FUNCTION_ARGS);
 Datum		gbt_cash_consistent(PG_FUNCTION_ARGS);
+Datum		gbt_cash_distance(PG_FUNCTION_ARGS);
 Datum		gbt_cash_penalty(PG_FUNCTION_ARGS);
 Datum		gbt_cash_same(PG_FUNCTION_ARGS);
 
@@ -71,6 +73,12 @@ gbt_cashkey_cmp(const void *a, const void *b)
 	return (ia->lower > ib->lower) ? 1 : -1;
 }
 
+static float8
+gbt_cash_dist(const void *a, const void *b)
+{
+	return GET_FLOAT_DISTANCE(Cash, a, b);
+}
+
 
 static const gbtree_ninfo tinfo =
 {
@@ -81,10 +89,33 @@ static const gbtree_ninfo tinfo =
 	gbt_casheq,
 	gbt_cashle,
 	gbt_cashlt,
-	gbt_cashkey_cmp
+	gbt_cashkey_cmp,
+	gbt_cash_dist
 };
 
 
+PG_FUNCTION_INFO_V1(cash_dist);
+Datum		cash_dist(PG_FUNCTION_ARGS);
+Datum
+cash_dist(PG_FUNCTION_ARGS)
+{
+	Cash		a = PG_GETARG_CASH(0);
+	Cash		b = PG_GETARG_CASH(1);
+	Cash		r;
+	Cash		ra;
+
+	r = a - b;
+	ra = Abs(r);
+
+	/* Overflow check. */
+	if (ra < 0 || (!SAMESIGN(a, b) && !SAMESIGN(r, a)))
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("money out of range")));
+
+	PG_RETURN_CASH(ra);
+}
+
 /**************************************************
  * Cash ops
  **************************************************/
@@ -125,6 +156,25 @@ gbt_cash_consistent(PG_FUNCTION_ARGS)
 
 
 Datum
+gbt_cash_distance(PG_FUNCTION_ARGS)
+{
+	GISTENTRY  *entry = (GISTENTRY *) PG_GETARG_POINTER(0);
+	Cash		query = PG_GETARG_CASH(1);
+
+	/* Oid		subtype = PG_GETARG_OID(3); */
+	cashKEY    *kkk = (cashKEY *) DatumGetPointer(entry->key);
+	GBT_NUMKEY_R key;
+
+	key.lower = (GBT_NUMKEY *) &kkk->lower;
+	key.upper = (GBT_NUMKEY *) &kkk->upper;
+
+	PG_RETURN_FLOAT8(
+				   gbt_num_distance(&key, (void *) &query, GIST_LEAF(entry), &tinfo)
+		);
+}
+
+
+Datum
 gbt_cash_union(PG_FUNCTION_ARGS)
 {
 	GistEntryVector *entryvec = (GistEntryVector *) PG_GETARG_POINTER(0);