From ecba5fa1d0c178dd4b5043cc6fc3973304ffe470 Mon Sep 17 00:00:00 2001
From: Martine Lenders <m.lenders@fu-berlin.de>
Date: Fri, 19 Feb 2021 11:28:01 +0100
Subject: [PATCH] gnrc_pktbuf_static: expose _align() function to be used for
 tests

---
 sys/Makefile.include                          |  4 ++
 sys/net/gnrc/pktbuf_static/Makefile.include   |  2 +
 .../gnrc/pktbuf_static/gnrc_pktbuf_static.c   | 14 +----
 .../pktbuf_static/include/pktbuf_static.h     | 58 +++++++++++++++++++
 4 files changed, 65 insertions(+), 13 deletions(-)
 create mode 100644 sys/net/gnrc/pktbuf_static/Makefile.include
 create mode 100644 sys/net/gnrc/pktbuf_static/include/pktbuf_static.h

diff --git a/sys/Makefile.include b/sys/Makefile.include
index 875f9c6bcd..058ed847e2 100644
--- a/sys/Makefile.include
+++ b/sys/Makefile.include
@@ -21,6 +21,10 @@ ifneq (,$(filter gnrc_pktbuf,$(USEMODULE)))
   include $(RIOTBASE)/sys/net/gnrc/pktbuf/Makefile.include
 endif
 
+ifneq (,$(filter gnrc_pktbuf_static,$(USEMODULE)))
+  include $(RIOTBASE)/sys/net/gnrc/pktbuf_static/Makefile.include
+endif
+
 ifneq (,$(filter malloc_thread_safe,$(USEMODULE)))
   include $(RIOTBASE)/sys/malloc_thread_safe/Makefile.include
 endif
diff --git a/sys/net/gnrc/pktbuf_static/Makefile.include b/sys/net/gnrc/pktbuf_static/Makefile.include
new file mode 100644
index 0000000000..6509bb8e78
--- /dev/null
+++ b/sys/net/gnrc/pktbuf_static/Makefile.include
@@ -0,0 +1,2 @@
+USEMODULE_INCLUDES_gnrc_pktbuf_static := $(LAST_MAKEFILEDIR)/include
+USEMODULE_INCLUDES += $(USEMODULE_INCLUDES_gnrc_pktbuf_static)
diff --git a/sys/net/gnrc/pktbuf_static/gnrc_pktbuf_static.c b/sys/net/gnrc/pktbuf_static/gnrc_pktbuf_static.c
index 3124b6d557..30fc9f2050 100644
--- a/sys/net/gnrc/pktbuf_static/gnrc_pktbuf_static.c
+++ b/sys/net/gnrc/pktbuf_static/gnrc_pktbuf_static.c
@@ -31,17 +31,11 @@
 #include "net/gnrc/pkt.h"
 
 #include "pktbuf_internal.h"
+#include "pktbuf_static.h"
 
 #define ENABLE_DEBUG 0
 #include "debug.h"
 
-#define _ALIGNMENT_MASK    (sizeof(_unused_t) - 1)
-
-typedef struct _unused {
-    struct _unused *next;
-    unsigned int size;
-} _unused_t;
-
 /* The static buffer needs to be aligned to word size, so that its start
  * address can be casted to `_unused_t *` safely. Just allocating an array of
  * (word sized) uintptr_t is a trivial way to do this */
@@ -59,12 +53,6 @@ static gnrc_pktsnip_t *_create_snip(gnrc_pktsnip_t *next, const void *data, size
                                     gnrc_nettype_t type);
 static void *_pktbuf_alloc(size_t size);
 
-/* fits size to byte alignment */
-static inline size_t _align(size_t size)
-{
-    return (size + _ALIGNMENT_MASK) & ~(_ALIGNMENT_MASK);
-}
-
 static inline void _set_pktsnip(gnrc_pktsnip_t *pkt, gnrc_pktsnip_t *next,
                                 void *data, size_t size, gnrc_nettype_t type)
 {
diff --git a/sys/net/gnrc/pktbuf_static/include/pktbuf_static.h b/sys/net/gnrc/pktbuf_static/include/pktbuf_static.h
new file mode 100644
index 0000000000..dce6f8736e
--- /dev/null
+++ b/sys/net/gnrc/pktbuf_static/include/pktbuf_static.h
@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2014-2015 Martine S. Lenders <m.lenders@fu-berlin.de>
+ * Copyright (C) 2014-2021 Freie Universität Berlin
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @ingroup net_gnrc_pktbuf
+ * @brief   Internal definitions of the static implementation of
+ *          @ref net_gnrc_pktbuf
+ * @{
+ *
+ * @file
+ * @brief   Definitions of types and their alignment for usage in tests
+ *
+ * @author  Martine Lenders <m.lenders@fu-berlin.de>
+ */
+#ifndef PKTBUF_STATIC_H
+#define PKTBUF_STATIC_H
+
+#include <sys/types.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @brief   Mask to align packet buffer allocations with size of @ref _unused_t
+ */
+#define GNRC_PKTBUF_STATIC_ALIGN_MASK   (sizeof(_unused_t) - 1)
+
+/**
+ * @brief   Marks an unused section of the packet buffer arena array
+ */
+typedef struct _unused {
+    struct _unused *next;   /**< the next unused section */
+    unsigned int size;      /**< the size of the unused section */
+} _unused_t;
+
+/**
+ * @brief   Calculates the required space of a number of bytes including
+ *          alignment to the size of @ref _unused_t
+ */
+static inline size_t _align(size_t size)
+{
+    return (size + GNRC_PKTBUF_STATIC_ALIGN_MASK) &
+          ~(GNRC_PKTBUF_STATIC_ALIGN_MASK);
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* PKTBUF_STATIC_H */
+/** @} */