From 20eb9c8dae8a33a951e3e9d20cff6059787f7317 Mon Sep 17 00:00:00 2001
From: Erica Fischer <enf@pobox.com>
Date: Thu, 11 May 2023 12:20:00 -0700
Subject: [PATCH] Avoid crashing if there is a polygon ring containing only one
 point (#102)

---
 CHANGELOG.md |  4 ++++
 geometry.cpp | 10 ++++++++++
 version.hpp  |  2 +-
 3 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 77cd52cb..1c4b175b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+# 2.26.1
+
+* Avoid crashing if there is a polygon ring with only one point
+
 # 2.26.0
 
 * Fix bugs in --no-simplification-of-shared-nodes
diff --git a/geometry.cpp b/geometry.cpp
index 428d6ed8..da48c488 100644
--- a/geometry.cpp
+++ b/geometry.cpp
@@ -1049,6 +1049,16 @@ drawvec fix_polygon(drawvec &geom) {
 				}
 			}
 
+			// A polygon ring must contain at least three points
+			// (and really should contain four). If this one does
+			// not have enough, avoid a division by zero trying to
+			// calculate the centroid below.
+			if (j - i < 3) {
+				i = j - 1;
+				outer = 0;
+				continue;
+			}
+
 			// Make a temporary copy of the ring.
 			// Close it if it isn't closed.
 
diff --git a/version.hpp b/version.hpp
index 3756d66e..551372a4 100644
--- a/version.hpp
+++ b/version.hpp
@@ -1,6 +1,6 @@
 #ifndef VERSION_HPP
 #define VERSION_HPP
 
-#define VERSION "v2.26.0"
+#define VERSION "v2.26.1"
 
 #endif