From 8e74bbae6b12fbf0afe155b9ba3b8329426583d4 Mon Sep 17 00:00:00 2001
From: Simon Tatham <anakin@pobox.com>
Date: Fri, 2 Apr 2010 07:21:34 +0000
Subject: [PATCH] Dylan O'Donnell reports that Signpost hangs on trying to
 generate a 2x2 puzzle. Rule it out in validate_params().

[originally from svn r8913]
---
 signpost.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/signpost.c b/signpost.c
index 05d4eaf..d4812a2 100644
--- a/signpost.c
+++ b/signpost.c
@@ -423,6 +423,8 @@ static char *validate_params(game_params *params, int full)
 {
     if (params->w < 2 || params->h < 2)
 	return "Width and height must both be at least two";
+    if (params->w == 2 && params->h == 2)   /* leads to generation hang */
+	return "Width and height cannot both be two";
 
     return NULL;
 }