use COPY_ARRAY

Add a semantic patch for converting certain calls of memcpy(3) to
COPY_ARRAY() and apply that transformation to the code base.  The result
is
 shorter and safer code.  For now only consider calls where source and
destination have the same type, or in other words: easy cases.

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

1 files changed, 26 insertions, 0 deletions

diff --git a/contrib/coccinelle/array.cocci b/contrib/coccinelle/array.cocci
new file mode 100644
index 000000000..2d7f25d99
--- /dev/null
+++ b/contrib/coccinelle/array.cocci
@@ -0,0 +1,26 @@
+@@
+type T;
+T *dst;
+T *src;
+expression n;
+@@
+- memcpy(dst, src, n * sizeof(*dst));
++ COPY_ARRAY(dst, src, n);
+
+@@
+type T;
+T *dst;
+T *src;
+expression n;
+@@
+- memcpy(dst, src, n * sizeof(*src));
++ COPY_ARRAY(dst, src, n);
+
+@@
+type T;
+T *dst;
+T *src;
+expression n;
+@@
+- memcpy(dst, src, n * sizeof(T));
++ COPY_ARRAY(dst, src, n);