From 0de38647f12520860a47bf4f4cd66b882ff1ccb8 Mon Sep 17 00:00:00 2001
From: Ewan Mellor <commits@ewanmellor.org>
Date: Wed, 21 Dec 2022 11:58:10 -0800
Subject: [PATCH] Hook up the -o flag from Hannes Achleitner (changeset
 25364cc).

This adds handling for GIT_DIFF_IMAGE_OUTPUT_DIR as an environment variable,
and creates a filename for each comparison to pass through the -o flag.
---
 git_diff_image | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/git_diff_image b/git_diff_image
index 5d5ea0b..382a11e 100755
--- a/git_diff_image
+++ b/git_diff_image
@@ -63,5 +63,19 @@ then
   e_flag='-e'
 fi
 
+o_flag=''
+if [ -n "${GIT_DIFF_IMAGE_OUTPUT_DIR-}" ]
+then
+    mkdir -p "$GIT_DIFF_IMAGE_OUTPUT_DIR"
+    destfile=''
+    if [ "$name1" -ne '/dev/null' ]
+    then
+        destfile=$(basename "$name1")
+    else
+        destfile=$(basename "$name2")
+    fi
+    o_flag="-o $GIT_DIFF_IMAGE_OUTPUT_DIR/$destfile"
+fi
 
-exec "$thisdir/diff-image" $e_flag -n "$name1" -N "$name2" "$f1" "$f2"
+
+exec "$thisdir/diff-image" $e_flag $o_flag -n "$name1" -N "$name2" "$f1" "$f2"