First step to vmod code maintenance automation

coccinelle/README.rst

+This directory contains `coccinelle`_ patches to facilitate code
+maintenance.
+
+Each patch should, in a comment section, explain its purpose.
+
+Unless noted otherwise, all patches should work when invoked as::
+
+	spatch --dir . --in-place --sp-file $COCCI
+
+.. _coccinelle: http://coccinelle.lip6.fr/

coccinelle/vmod/WS_Reserve.cocci

+/*
+ * patch to change code with respect to #2969: Replacement of
+ * WS_Reserve(ws, sz) by WS_ReserveAll(ws) / WS_ReserveSize(ws, sz)
+ *
+ * NOTE this patch does not check/fix error handling:
+ * - WS_ReserveAll(ws) : Always needs WS_Release(ws, sz)
+ * - WS_ReserveSize(ws, sz): needs WS_Release(ws, sz) if retval != 0
+ */
+@@
+expression ws;
+identifier ptr;
+@@
+
+-ptr = WS_Reserve(ws, 0);
++ptr = WS_ReserveAll(ws);
+
+@@
+expression ws, sz;
+identifier ptr;
+@@
+
+-ptr = WS_Reserve(ws, sz);
++ptr = WS_ReserveSize(ws, sz);

doc/changes.rst

@@ -60,7 +60,8 @@ C APIs (for vmod and utility authors)
     It will only leave the workspace reserved if the reservation
     request could be fulfilled.
 
-
+  We provide a script to automate this change in the ``coccinelle``
+  subdirectory of the source tree.
 
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 Varnish Cache 6.2.0 (2019-03-15)