Use Zephyr heap for Zephyr targets

[pawszw2]

Is your feature request related to a problem? Please describe.

Zephyr heap is efficient way to use memory on platforms using Zephyr OS and it isn't hard to introduce.

Describe the solution you would like

For Zephyr targets I'd like libcoap to use k_malloc, k_realloc and k_free instead of regular malloc, realloc and free. It would look like this:

--- a/src/coap_mem.c
+++ b/src/coap_mem.c
@@ -479,7 +479,65 @@ coap_realloc_type(coap_memory_tag_t type, void *p, size_t size) {
 }
 #else /* ! RIOT_VERSION && ! MODULE_MEMARRAY */

-#if defined(HAVE_MALLOC) || defined(__MINGW32__)
+#if defined(__ZEPHYR__)
+
+#include <zephyr/kernel.h>
+
+void
+coap_memory_init(void) {
+}
+
+void *
+coap_malloc_type(coap_memory_tag_t type, size_t size) {
+  void *ptr;
+
+  (void)type;
+  ptr = k_malloc(size);
+#if COAP_MEMORY_TYPE_TRACK
+  assert(type < COAP_MEM_TAG_LAST);
+  if (ptr) {
+    track_counts[type]++;
+    if (track_counts[type] > peak_counts[type])
+      peak_counts[type] = track_counts[type];
+  } else {
+    fail_counts[type]++;
+  }
+#endif /* COAP_MEMORY_TYPE_TRACK */
+  return ptr;
+}
+
+void *
+coap_realloc_type(coap_memory_tag_t type, void *p, size_t size) {
+  void *ptr;
+
+  (void)type;
+  ptr = k_realloc(p, size);
+#if COAP_MEMORY_TYPE_TRACK
+  if (ptr) {
+    assert(type < COAP_MEM_TAG_LAST);
+    if (!p)
+      track_counts[type]++;
+    if (track_counts[type] > peak_counts[type])
+      peak_counts[type] = track_counts[type];
+  } else {
+    fail_counts[type]++;
+  }
+#endif /* COAP_MEMORY_TYPE_TRACK */
+  return ptr;
+}
+
+void
+coap_free_type(coap_memory_tag_t type, void *p) {
+  (void)type;
+#if COAP_MEMORY_TYPE_TRACK
+  assert(type < COAP_MEM_TAG_LAST);
+  if (p)
+    track_counts[type]--;
+#endif /* COAP_MEMORY_TYPE_TRACK */
+  k_free(p);
+}
+
+#elif defined(HAVE_MALLOC) || defined(__MINGW32__)
 #include <stdlib.h>

 void
@@ -536,7 +594,7 @@ coap_free_type(coap_memory_tag_t type, void *p) {
   free(p);
 }

-#else /* ! HAVE_MALLOC  && !__MINGW32__ */
+#else /* ! HAVE_MALLOC  && !__MINGW32__ && !__ZEPHYR__*/

 #ifdef WITH_CONTIKI
 #include "lib/heapmem.h"

Describe alternatives you have considered

Another option is to make configurable, whether to use k_ functions or regular ones in terms of memory management.

[mrdeep1]

This change looks perfectly reasonable to me as is. Can you please raise a PR for it?

[mrdeep1]

Closed as now merged into the develop branch.