From 4b009649c65053d2f0bcd220fc7d0f86b9ddf311 Mon Sep 17 00:00:00 2001
From: Gunar Schorcht <gunar@schorcht.net>
Date: Sun, 3 Feb 2019 18:59:27 +0100
Subject: [PATCH] cpu/atmega_common: changes for common heap command

---
 cpu/atmega_common/cpu.c              | 22 ++++++++++++++++++++++
 cpu/atmega_common/include/cpu_conf.h |  5 +++++
 2 files changed, 27 insertions(+)

diff --git a/cpu/atmega_common/cpu.c b/cpu/atmega_common/cpu.c
index f02469beb4..e1f9556dd9 100644
--- a/cpu/atmega_common/cpu.c
+++ b/cpu/atmega_common/cpu.c
@@ -112,6 +112,28 @@ void cpu_init(void)
     periph_init();
 }
 
+struct __freelist {
+    size_t size;
+    struct __freelist *next;
+};
+
+extern struct __freelist *__flp;
+extern char *__malloc_heap_start;
+extern char *__malloc_heap_end;
+extern char *__brkval;
+
+void heap_stats(void)
+{
+    int heap_size = __malloc_heap_end - __malloc_heap_start;
+    int free = __malloc_heap_end - __brkval;
+    struct __freelist *fp;
+    for (fp = __flp; fp; fp = fp->next) {
+        free += fp->size;
+    }
+    printf("heap: %d (used %d, free %d) [bytes]\n",
+           heap_size, heap_size - free, free);
+}
+
 /* This is a vector which is aliased to __vector_default,
  * the vector executed when an ISR fires with no accompanying
  * ISR handler. This may be used along with the ISR() macro to
diff --git a/cpu/atmega_common/include/cpu_conf.h b/cpu/atmega_common/include/cpu_conf.h
index 7eacb5bf2b..37ede8582f 100644
--- a/cpu/atmega_common/include/cpu_conf.h
+++ b/cpu/atmega_common/include/cpu_conf.h
@@ -56,6 +56,11 @@ extern "C" {
  */
 #define PUF_SRAM_ATTRIBUTES __attribute__((used, section(".noinit")))
 
+/**
+ * @brief   Declare the heap_stats function as available
+ */
+#define HAVE_HEAP_STATS
+
 #ifdef __cplusplus
 }
 #endif