From d9bcf9b9cc0995150491d225719255d1671236a2 Mon Sep 17 00:00:00 2001
From: Benjamin Berg <bberg@redhat.com>
Date: Fri, 6 Dec 2019 18:54:49 +0100
Subject: [PATCH] fpi-assembling: Accept error of zero

Rather than discarding a zero error, check that the constraints are
sane. This way a perfect match is possible.
---
 libfprint/fpi-assembling.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/libfprint/fpi-assembling.c b/libfprint/fpi-assembling.c
index 2b55ee3d..a809a2dc 100644
--- a/libfprint/fpi-assembling.c
+++ b/libfprint/fpi-assembling.c
@@ -52,6 +52,9 @@ calc_error (struct fpi_frame_asmbl_ctx *ctx,
   width = ctx->frame_width - (dx > 0 ? dx : -dx);
   height = ctx->frame_height - dy;
 
+  if (height == 0 || width == 0)
+    return INT_MAX;
+
   y1 = 0;
   y2 = dy;
   i = 0;
@@ -86,9 +89,6 @@ calc_error (struct fpi_frame_asmbl_ctx *ctx,
   err *= (ctx->frame_height * ctx->frame_width);
   err /= (height * width);
 
-  if (err == 0)
-    return INT_MAX;
-
   return err;
 }