From: René Scharfe <l.s.r@web.de>
Date: Sat, 15 Jul 2017 20:20:54 +0000 (+0200)
Subject: apply: use COPY_ARRAY and MOVE_ARRAY in update_image()
X-Git-Tag: v2.14.2~54^2~1
X-Git-Url: https://git.lorimer.id.au/gitweb.git/diff_plain/177366415b95fb72bc2c37d55a936ff101986285?ds=inline;hp=--cc

apply: use COPY_ARRAY and MOVE_ARRAY in update_image()

Simplify the code by using the helper macros COPY_ARRAY and MOVE_ARRAY,
which also makes them more robust in the case we copy or move no lines,
as they allow using NULL points in that case, while memcpy(3) and
memmove(3) don't.

Found with Clang's UBSan.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---

177366415b95fb72bc2c37d55a936ff101986285
diff --git a/apply.c b/apply.c
index f2d599141d..40707ca50c 100644
--- a/apply.c
+++ b/apply.c
@@ -2809,13 +2809,10 @@ static void update_image(struct apply_state *state,
 		img->line_allocated = img->line;
 	}
 	if (preimage_limit != postimage->nr)
-		memmove(img->line + applied_pos + postimage->nr,
-			img->line + applied_pos + preimage_limit,
-			(img->nr - (applied_pos + preimage_limit)) *
-			sizeof(*img->line));
-	memcpy(img->line + applied_pos,
-	       postimage->line,
-	       postimage->nr * sizeof(*img->line));
+		MOVE_ARRAY(img->line + applied_pos + postimage->nr,
+			   img->line + applied_pos + preimage_limit,
+			   img->nr - (applied_pos + preimage_limit));
+	COPY_ARRAY(img->line + applied_pos, postimage->line, postimage->nr);
 	if (!state->allow_overlap)
 		for (i = 0; i < postimage->nr; i++)
 			img->line[applied_pos + i].flag |= LINE_PATCHED;