Fix diffstat and submodule diff output

The diffstat divided by zero when a commit changed no lines, and a
submodule change was printed with a hardcoded length that dropped a
digit of a sha-1 and most of a sha-256.

1 file changed, 11 insertions, 7 deletions

diff --git a/source/ui-diff.c b/source/ui-diff.c
index 6cfa697..04bbecc 100644
--- a/source/ui-diff.c
+++ b/source/ui-diff.c
@@ -117,11 +117,11 @@ static void print_fileinfo(struct fileinfo *info)
 	html("</td><td class='graph'>");
 	htmlf("<table summary='file diffstat' width='%d%%'><tr>", (max_changes > 100 ? 100 : max_changes));
 	htmlf("<td class='add' style='width: %.1f%%;'/>",
-	      info->added * 100.0 / max_changes);
+	      info->added * 100.0 / (max_changes ? max_changes : 1));
 	htmlf("<td class='rem' style='width: %.1f%%;'/>",
-	      info->removed * 100.0 / max_changes);
+	      info->removed * 100.0 / (max_changes ? max_changes : 1));
 	htmlf("<td class='none' style='width: %.1f%%;'/>",
-	      (max_changes - info->removed - info->added) * 100.0 / max_changes);
+	      (max_changes - info->removed - info->added) * 100.0 / (max_changes ? max_changes : 1));
 	html("</tr></table></td></tr>\n");
 }
 
@@ -314,10 +314,14 @@ static void filepair_cb(struct diff_filepair *pair)
 	if (use_ssdiff)
 		cgit_ssdiff_header_end();
 	if (S_ISGITLINK(pair->one->mode) || S_ISGITLINK(pair->two->mode)) {
-		if (S_ISGITLINK(pair->one->mode))
-			print_line_fn(fmt("-Subproject %s", oid_to_hex(&pair->one->oid)), 52);
-		if (S_ISGITLINK(pair->two->mode))
-			print_line_fn(fmt("+Subproject %s", oid_to_hex(&pair->two->oid)), 52);
+		if (S_ISGITLINK(pair->one->mode)) {
+			char *l = fmt("-Subproject %s", oid_to_hex(&pair->one->oid));
+			print_line_fn(l, strlen(l) + 1);
+		}
+		if (S_ISGITLINK(pair->two->mode)) {
+			char *l = fmt("+Subproject %s", oid_to_hex(&pair->two->oid));
+			print_line_fn(l, strlen(l) + 1);
+		}
 		if (use_ssdiff)
 			cgit_ssdiff_footer();
 		return;