v11-0018-error-safe-for-casting-geometry-data-type.patch

From 78f39bc072a0e228ea225b512d4a7940f9b74e63 Mon Sep 17 00:00:00 2001
From: jian he <jian.universality@gmail.com>
Date: Mon, 24 Nov 2025 16:38:23 +0800
Subject: [PATCH v11 18/20] error safe for casting geometry data type

select castsource::regtype, casttarget::regtype, pp.prosrc
from pg_cast pc join pg_proc pp on pp.oid = pc.castfunc
join pg_type pt on pt.oid = castsource
join pg_type pt1 on pt1.oid = casttarget
and pc.castfunc > 0 and  pt.typarray <> 0
and pt.typnamespace = 'pg_catalog'::regnamespace
and pt1.typnamespace = 'pg_catalog'::regnamespace
and (pt.typcategory  = 'G' or pt1.typcategory  = 'G')
order by castsource::regtype, casttarget::regtype;

 castsource | casttarget |    prosrc
------------+------------+---------------
 point      | box        | point_box
 lseg       | point      | lseg_center
 path       | polygon    | path_poly
 box        | point      | box_center
 box        | lseg       | box_diagonal
 box        | polygon    | box_poly
 box        | circle     | box_circle
 polygon    | point      | poly_center
 polygon    | path       | poly_path
 polygon    | box        | poly_box
 polygon    | circle     | poly_circle
 circle     | point      | circle_center
 circle     | box        | circle_box
 circle     | polygon    |
(14 rows)

already error safe: point_box, box_diagonal, box_poly, poly_path, poly_box, circle_center
almost error safe: path_poly
can not error safe: cast circle to polygon, because it's a SQL function

discussion: https://postgr.es/m/CACJufxHCMzrHOW=wRe8L30rMhB3sjwAv1LE928Fa7sxMu1Tx-g@mail.gmail.com
---
 src/backend/access/spgist/spgproc.c |   2 +-
 src/backend/utils/adt/geo_ops.c     | 225 +++++++++++++++++++++++-----
 src/backend/utils/adt/geo_spgist.c  |   2 +-
 src/include/utils/float.h           |  77 ++++++++++
 src/include/utils/geo_decls.h       |   4 +-
 5 files changed, 271 insertions(+), 39 deletions(-)

diff --git a/src/backend/access/spgist/spgproc.c b/src/backend/access/spgist/spgproc.c
index 660009291da..b3e0fbc59ba 100644
--- a/src/backend/access/spgist/spgproc.c
+++ b/src/backend/access/spgist/spgproc.c
@@ -51,7 +51,7 @@ point_box_distance(Point *point, BOX *box)
 	else
 		dy = 0.0;
 
-	return HYPOT(dx, dy);
+	return HYPOT(dx, dy, NULL);
 }
 
 /*
diff --git a/src/backend/utils/adt/geo_ops.c b/src/backend/utils/adt/geo_ops.c
index 377a1b3f3ad..bae8730c347 100644
--- a/src/backend/utils/adt/geo_ops.c
+++ b/src/backend/utils/adt/geo_ops.c
@@ -78,11 +78,14 @@ enum path_delim
 /* Routines for points */
 static inline void point_construct(Point *result, float8 x, float8 y);
 static inline void point_add_point(Point *result, Point *pt1, Point *pt2);
+static inline bool point_add_point_safe(Point *result, Point *pt1, Point *pt2,
+										Node *escontext);
 static inline void point_sub_point(Point *result, Point *pt1, Point *pt2);
 static inline void point_mul_point(Point *result, Point *pt1, Point *pt2);
 static inline void point_div_point(Point *result, Point *pt1, Point *pt2);
 static inline bool point_eq_point(Point *pt1, Point *pt2);
 static inline float8 point_dt(Point *pt1, Point *pt2);
+static inline float8 point_dt_safe(Point *pt1, Point *pt2, Node *escontext);
 static inline float8 point_sl(Point *pt1, Point *pt2);
 static int	point_inside(Point *p, int npts, Point *plist);
 
@@ -109,6 +112,7 @@ static float8 lseg_closept_lseg(Point *result, LSEG *on_lseg, LSEG *to_lseg);
 /* Routines for boxes */
 static inline void box_construct(BOX *result, Point *pt1, Point *pt2);
 static void box_cn(Point *center, BOX *box);
+static bool box_cn_safe(Point *center, BOX *box, Node* escontext);
 static bool box_ov(BOX *box1, BOX *box2);
 static float8 box_ar(BOX *box);
 static float8 box_ht(BOX *box);
@@ -125,7 +129,7 @@ static float8 circle_ar(CIRCLE *circle);
 
 /* Routines for polygons */
 static void make_bound_box(POLYGON *poly);
-static void poly_to_circle(CIRCLE *result, POLYGON *poly);
+static bool poly_to_circle_safe(CIRCLE *result, POLYGON *poly, Node *escontext);
 static bool lseg_inside_poly(Point *a, Point *b, POLYGON *poly, int start);
 static bool poly_contain_poly(POLYGON *contains_poly, POLYGON *contained_poly);
 static bool plist_same(int npts, Point *p1, Point *p2);
@@ -851,7 +855,8 @@ box_center(PG_FUNCTION_ARGS)
 	BOX		   *box = PG_GETARG_BOX_P(0);
 	Point	   *result = (Point *) palloc(sizeof(Point));
 
-	box_cn(result, box);
+	if (!box_cn_safe(result, box, fcinfo->context))
+		PG_RETURN_NULL();
 
 	PG_RETURN_POINT_P(result);
 }
@@ -871,10 +876,33 @@ box_ar(BOX *box)
 static void
 box_cn(Point *center, BOX *box)
 {
-	center->x = float8_div(float8_pl(box->high.x, box->low.x), 2.0);
-	center->y = float8_div(float8_pl(box->high.y, box->low.y), 2.0);
+	(void) box_cn_safe(center, box, NULL);
 }
 
+static bool
+box_cn_safe(Point *center, BOX *box, Node* escontext)
+{
+	float8		x;
+	float8		y;
+
+	x = float8_pl_safe(box->high.x, box->low.x, escontext);
+	if (SOFT_ERROR_OCCURRED(escontext))
+		return false;
+
+	center->x = float8_div_safe(x, 2.0, escontext);
+	if (SOFT_ERROR_OCCURRED(escontext))
+		return false;
+
+	y = float8_pl_safe(box->high.y, box->low.y, escontext);
+	if (SOFT_ERROR_OCCURRED(escontext))
+		return false;
+
+	center->y = float8_div_safe(y, 2.0, escontext);
+	if (SOFT_ERROR_OCCURRED(escontext))
+		return false;
+
+	return true;
+}
 
 /*		box_wd	-		returns the width (length) of the box
  *								  (horizontal magnitude).
@@ -1276,7 +1304,7 @@ line_distance(PG_FUNCTION_ARGS)
 
 	PG_RETURN_FLOAT8(float8_div(fabs(float8_mi(l1->C,
 											   float8_mul(ratio, l2->C))),
-								HYPOT(l1->A, l1->B)));
+								HYPOT(l1->A, l1->B, NULL)));
 }
 
 /* line_interpt()
@@ -2001,9 +2029,27 @@ point_distance(PG_FUNCTION_ARGS)
 static inline float8
 point_dt(Point *pt1, Point *pt2)
 {
-	return HYPOT(float8_mi(pt1->x, pt2->x), float8_mi(pt1->y, pt2->y));
+	return point_dt_safe(pt1, pt2, NULL);
 }
 
+static inline float8
+point_dt_safe(Point *pt1, Point *pt2, Node *escontext)
+{
+	float8		x;
+	float8		y;
+
+	x = float8_mi_safe(pt1->x, pt2->x, escontext);
+	if (SOFT_ERROR_OCCURRED(escontext))
+		return 0.0;
+
+	y  = float8_mi_safe(pt1->y, pt2->y, escontext);
+	if (SOFT_ERROR_OCCURRED(escontext))
+		return 0.0;
+
+	return HYPOT(x, y, escontext);
+}
+
+
 Datum
 point_slope(PG_FUNCTION_ARGS)
 {
@@ -2317,13 +2363,31 @@ lseg_center(PG_FUNCTION_ARGS)
 {
 	LSEG	   *lseg = PG_GETARG_LSEG_P(0);
 	Point	   *result;
+	float8		x;
+	float8		y;
 
 	result = (Point *) palloc(sizeof(Point));
 
-	result->x = float8_div(float8_pl(lseg->p[0].x, lseg->p[1].x), 2.0);
-	result->y = float8_div(float8_pl(lseg->p[0].y, lseg->p[1].y), 2.0);
+	x = float8_pl_safe(lseg->p[0].x, lseg->p[1].x, fcinfo->context);
+	if (SOFT_ERROR_OCCURRED(fcinfo->context))
+		goto fail;
+
+	result->x = float8_div_safe(x, 2.0, fcinfo->context);
+	if (SOFT_ERROR_OCCURRED(fcinfo->context))
+		goto fail;
+
+	y = float8_pl_safe(lseg->p[0].y, lseg->p[1].y, fcinfo->context);
+	if (SOFT_ERROR_OCCURRED(fcinfo->context))
+		goto fail;
+
+	result->y = float8_div_safe(y, 2.0, fcinfo->context);
+	if (SOFT_ERROR_OCCURRED(fcinfo->context))
+		goto fail;
 
 	PG_RETURN_POINT_P(result);
+
+fail:
+	PG_RETURN_NULL();
 }
 
 
@@ -4110,9 +4174,27 @@ construct_point(PG_FUNCTION_ARGS)
 static inline void
 point_add_point(Point *result, Point *pt1, Point *pt2)
 {
-	point_construct(result,
-					float8_pl(pt1->x, pt2->x),
-					float8_pl(pt1->y, pt2->y));
+	(void) point_add_point_safe(result, pt1, pt2, NULL);
+}
+
+static inline bool
+point_add_point_safe(Point *result, Point *pt1, Point *pt2,
+					 Node *escontext)
+{
+	float8		x;
+	float8		y;
+
+	x = float8_pl_safe(pt1->x, pt2->x, escontext);
+	if (SOFT_ERROR_OCCURRED(escontext))
+		return false;
+
+	y = float8_pl_safe(pt1->y, pt2->y, escontext);
+	if (SOFT_ERROR_OCCURRED(escontext))
+		return false;
+
+	point_construct(result, x, y);
+
+	return true;
 }
 
 Datum
@@ -4458,7 +4540,7 @@ path_poly(PG_FUNCTION_ARGS)
 
 	/* This is not very consistent --- other similar cases return NULL ... */
 	if (!path->closed)
-		ereport(ERROR,
+		ereturn(fcinfo->context, (Datum) 0,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("open path cannot be converted to polygon")));
 
@@ -4508,7 +4590,9 @@ poly_center(PG_FUNCTION_ARGS)
 
 	result = (Point *) palloc(sizeof(Point));
 
-	poly_to_circle(&circle, poly);
+	if (!poly_to_circle_safe(&circle, poly, fcinfo->context))
+		PG_RETURN_NULL();
+
 	*result = circle.center;
 
 	PG_RETURN_POINT_P(result);
@@ -5005,7 +5089,7 @@ circle_mul_pt(PG_FUNCTION_ARGS)
 	result = (CIRCLE *) palloc(sizeof(CIRCLE));
 
 	point_mul_point(&result->center, &circle->center, point);
-	result->radius = float8_mul(circle->radius, HYPOT(point->x, point->y));
+	result->radius = float8_mul(circle->radius, HYPOT(point->x, point->y, NULL));
 
 	PG_RETURN_CIRCLE_P(result);
 }
@@ -5020,7 +5104,7 @@ circle_div_pt(PG_FUNCTION_ARGS)
 	result = (CIRCLE *) palloc(sizeof(CIRCLE));
 
 	point_div_point(&result->center, &circle->center, point);
-	result->radius = float8_div(circle->radius, HYPOT(point->x, point->y));
+	result->radius = float8_div(circle->radius, HYPOT(point->x, point->y, NULL));
 
 	PG_RETURN_CIRCLE_P(result);
 }
@@ -5191,14 +5275,30 @@ circle_box(PG_FUNCTION_ARGS)
 
 	box = (BOX *) palloc(sizeof(BOX));
 
-	delta = float8_div(circle->radius, sqrt(2.0));
+	delta = float8_div_safe(circle->radius, sqrt(2.0), fcinfo->context);
+	if (SOFT_ERROR_OCCURRED(fcinfo->context))
+		goto fail;
 
-	box->high.x = float8_pl(circle->center.x, delta);
-	box->low.x = float8_mi(circle->center.x, delta);
-	box->high.y = float8_pl(circle->center.y, delta);
-	box->low.y = float8_mi(circle->center.y, delta);
+	box->high.x = float8_pl_safe(circle->center.x, delta, fcinfo->context);
+	if (SOFT_ERROR_OCCURRED(fcinfo->context))
+		goto fail;
+
+	box->low.x = float8_mi_safe(circle->center.x, delta, fcinfo->context);
+	if (SOFT_ERROR_OCCURRED(fcinfo->context))
+		goto fail;
+
+	box->high.y = float8_pl_safe(circle->center.y, delta, fcinfo->context);
+	if (SOFT_ERROR_OCCURRED(fcinfo->context))
+		goto fail;
+
+	box->low.y = float8_mi_safe(circle->center.y, delta, fcinfo->context);
+	if (SOFT_ERROR_OCCURRED(fcinfo->context))
+		goto fail;
 
 	PG_RETURN_BOX_P(box);
+
+fail:
+	PG_RETURN_NULL();
 }
 
 /* box_circle()
@@ -5209,15 +5309,35 @@ box_circle(PG_FUNCTION_ARGS)
 {
 	BOX		   *box = PG_GETARG_BOX_P(0);
 	CIRCLE	   *circle;
+	float8		x;
+	float8		y;
 
 	circle = (CIRCLE *) palloc(sizeof(CIRCLE));
 
-	circle->center.x = float8_div(float8_pl(box->high.x, box->low.x), 2.0);
-	circle->center.y = float8_div(float8_pl(box->high.y, box->low.y), 2.0);
+	x = float8_pl_safe(box->high.x, box->low.x, fcinfo->context);
+	if (SOFT_ERROR_OCCURRED(fcinfo->context))
+		goto fail;
 
-	circle->radius = point_dt(&circle->center, &box->high);
+	circle->center.x = float8_div_safe(x, 2.0, fcinfo->context);
+	if (SOFT_ERROR_OCCURRED(fcinfo->context))
+		goto fail;
+
+	y = float8_pl_safe(box->high.y, box->low.y, fcinfo->context);
+	if (SOFT_ERROR_OCCURRED(fcinfo->context))
+		goto fail;
+
+	circle->center.y = float8_div_safe(y, 2.0, fcinfo->context);
+	if (SOFT_ERROR_OCCURRED(fcinfo->context))
+		goto fail;
+
+	circle->radius = point_dt_safe(&circle->center, &box->high, fcinfo->context);
+	if (SOFT_ERROR_OCCURRED(fcinfo->context))
+		goto fail;
 
 	PG_RETURN_CIRCLE_P(circle);
+
+fail:
+	PG_RETURN_NULL();
 }
 
 
@@ -5281,10 +5401,11 @@ circle_poly(PG_FUNCTION_ARGS)
  * XXX This algorithm should use weighted means of line segments
  *	rather than straight average values of points - tgl 97/01/21.
  */
-static void
-poly_to_circle(CIRCLE *result, POLYGON *poly)
+static bool
+poly_to_circle_safe(CIRCLE *result, POLYGON *poly, Node *escontext)
 {
 	int			i;
+	float8		x;
 
 	Assert(poly->npts > 0);
 
@@ -5293,14 +5414,42 @@ poly_to_circle(CIRCLE *result, POLYGON *poly)
 	result->radius = 0;
 
 	for (i = 0; i < poly->npts; i++)
-		point_add_point(&result->center, &result->center, &poly->p[i]);
-	result->center.x = float8_div(result->center.x, poly->npts);
-	result->center.y = float8_div(result->center.y, poly->npts);
+	{
+		if (!point_add_point_safe(&result->center,
+								  &result->center,
+								  &poly->p[i],
+								  escontext))
+			return false;
+	}
+
+	result->center.x = float8_div_safe(result->center.x,
+									   poly->npts,
+									   escontext);
+	if (SOFT_ERROR_OCCURRED(escontext))
+		return false;
+
+	result->center.y = float8_div_safe(result->center.y,
+									   poly->npts,
+									   escontext);
+	if (SOFT_ERROR_OCCURRED(escontext))
+		return false;
 
 	for (i = 0; i < poly->npts; i++)
-		result->radius = float8_pl(result->radius,
-								   point_dt(&poly->p[i], &result->center));
-	result->radius = float8_div(result->radius, poly->npts);
+	{
+		x = point_dt_safe(&poly->p[i], &result->center, escontext);
+		if (SOFT_ERROR_OCCURRED(escontext))
+			return false;
+
+		result->radius = float8_pl_safe(result->radius, x, escontext);
+		if (SOFT_ERROR_OCCURRED(escontext))
+			return false;
+	}
+
+	result->radius = float8_div_safe(result->radius, poly->npts, escontext);
+	if (SOFT_ERROR_OCCURRED(escontext))
+		return false;
+
+	return true;
 }
 
 Datum
@@ -5311,7 +5460,8 @@ poly_circle(PG_FUNCTION_ARGS)
 
 	result = (CIRCLE *) palloc(sizeof(CIRCLE));
 
-	poly_to_circle(result, poly);
+	if (!poly_to_circle_safe(result, poly, fcinfo->context))
+		PG_RETURN_NULL();
 
 	PG_RETURN_CIRCLE_P(result);
 }
@@ -5516,7 +5666,7 @@ plist_same(int npts, Point *p1, Point *p2)
  *-----------------------------------------------------------------------
  */
 float8
-pg_hypot(float8 x, float8 y)
+pg_hypot(float8 x, float8 y, Node *escontext)
 {
 	float8		yx,
 				result;
@@ -5554,9 +5704,14 @@ pg_hypot(float8 x, float8 y)
 	result = x * sqrt(1.0 + (yx * yx));
 
 	if (unlikely(isinf(result)))
-		float_overflow_error();
+		ereturn(escontext, 0.0,
+			errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+			errmsg("value out of range: overflow"));
+
 	if (unlikely(result == 0.0))
-		float_underflow_error();
+		ereturn(escontext, 0.0,
+				errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				errmsg("value out of range: underflow"));
 
 	return result;
 }
diff --git a/src/backend/utils/adt/geo_spgist.c b/src/backend/utils/adt/geo_spgist.c
index fec33e95372..ffffd3cd2de 100644
--- a/src/backend/utils/adt/geo_spgist.c
+++ b/src/backend/utils/adt/geo_spgist.c
@@ -390,7 +390,7 @@ pointToRectBoxDistance(Point *point, RectBox *rect_box)
 	else
 		dy = 0;
 
-	return HYPOT(dx, dy);
+	return HYPOT(dx, dy, NULL);
 }
 
 
diff --git a/src/include/utils/float.h b/src/include/utils/float.h
index fc2a9cf6475..aec376ffc56 100644
--- a/src/include/utils/float.h
+++ b/src/include/utils/float.h
@@ -121,6 +121,21 @@ float8_pl(const float8 val1, const float8 val2)
 	return result;
 }
 
+/* error safe version of float8_pl */
+static inline float8
+float8_pl_safe(const float8 val1, const float8 val2, struct Node *escontext)
+{
+	float8		result;
+
+	result = val1 + val2;
+	if (unlikely(isinf(result)) && !isinf(val1) && !isinf(val2))
+		ereturn(escontext, 0,
+				errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				errmsg("value out of range: overflow"));
+
+	return result;
+}
+
 static inline float4
 float4_mi(const float4 val1, const float4 val2)
 {
@@ -145,6 +160,21 @@ float8_mi(const float8 val1, const float8 val2)
 	return result;
 }
 
+/* error safe version of float8_mi */
+static inline float8
+float8_mi_safe(const float8 val1, const float8 val2, struct Node *escontext)
+{
+	float8		result;
+
+	result = val1 - val2;
+	if (unlikely(isinf(result)) && !isinf(val1) && !isinf(val2))
+		ereturn(escontext, 0,
+				errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				errmsg("value out of range: overflow"));
+
+	return result;
+}
+
 static inline float4
 float4_mul(const float4 val1, const float4 val2)
 {
@@ -173,6 +203,27 @@ float8_mul(const float8 val1, const float8 val2)
 	return result;
 }
 
+/* error safe version of float8_mul */
+static inline float8
+float8_mul_safe(const float8 val1, const float8 val2, struct Node *escontext)
+{
+	float8		result;
+
+	result = val1 * val2;
+
+	if (unlikely(isinf(result)) && !isinf(val1) && !isinf(val2))
+		ereturn(escontext, 0,
+				errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				errmsg("value out of range: overflow"));
+
+	if (unlikely(result == 0.0) && val1 != 0.0 && val2 != 0.0)
+		ereturn(escontext, 0,
+				errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				errmsg("value out of range: underflow"));
+
+	return result;
+}
+
 static inline float4
 float4_div(const float4 val1, const float4 val2)
 {
@@ -205,6 +256,32 @@ float8_div(const float8 val1, const float8 val2)
 	return result;
 }
 
+/* error safe version of float8_div */
+static inline float8
+float8_div_safe(const float8 val1, const float8 val2, struct Node *escontext)
+{
+	float8		result;
+
+	if (unlikely(val2 == 0.0) && !isnan(val1))
+		ereturn(escontext, 0,
+				errcode(ERRCODE_DIVISION_BY_ZERO),
+				errmsg("division by zero"));
+
+	result = val1 / val2;
+
+	if (unlikely(isinf(result)) && !isinf(val1))
+		ereturn(escontext, 0,
+				errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				errmsg("value out of range: overflow"));
+
+	if (unlikely(result == 0.0) && val1 != 0.0 && !isinf(val2))
+		ereturn(escontext, 0,
+				errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				errmsg("value out of range: underflow"));
+
+	return result;
+}
+
 /*
  * Routines for NaN-aware comparisons
  *
diff --git a/src/include/utils/geo_decls.h b/src/include/utils/geo_decls.h
index 8a9df75c93c..0056a26639f 100644
--- a/src/include/utils/geo_decls.h
+++ b/src/include/utils/geo_decls.h
@@ -88,7 +88,7 @@ FPge(double A, double B)
 #define FPge(A,B)				((A) >= (B))
 #endif
 
-#define HYPOT(A, B)				pg_hypot(A, B)
+#define HYPOT(A, B, escontext)				pg_hypot(A, B, escontext)
 
 /*---------------------------------------------------------------------
  * Point - (x,y)
@@ -280,6 +280,6 @@ CirclePGetDatum(const CIRCLE *X)
  * in geo_ops.c
  */
 
-extern float8 pg_hypot(float8 x, float8 y);
+extern float8 pg_hypot(float8 x, float8 y, Node *escontext);
 
 #endif							/* GEO_DECLS_H */
-- 
2.34.1