From 19b8d96ffe4a8e3041fda82b21619602fb7352a4 Mon Sep 17 00:00:00 2001
From: Jakub <106778416+MarekZegare4@users.noreply.github.com>
Date: Wed, 2 Sep 2026 09:02:53 +0200
Subject: [PATCH] fix(diag): report real heap/stack stats on ESP32, not just
 nRF52

DeviceDiag::getHeapStats()/getStackFreeBytes() only had an implementation
for NRF52_PLATFORM; every other platform fell through to the 0/0 stub, so
Diagnostics > Live showed "N/A" for Heap free and Stack free on ESP32
boards (Heltec v3/v4) -- exactly the boards where that number is most
useful to see. Added an ESP32 branch using heap_caps_get_free_size()/
heap_caps_get_total_size() (MALLOC_CAP_8BIT, matching the general-purpose
heap `new`/malloc() actually draw from) and the same
uxTaskGetStackHighWaterMark() call nRF52 already uses, since Arduino-ESP32
runs on FreeRTOS too.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
---
 src/helpers/DeviceDiag.cpp | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/src/helpers/DeviceDiag.cpp b/src/helpers/DeviceDiag.cpp
index 117dd72d..1581533b 100644
--- a/src/helpers/DeviceDiag.cpp
+++ b/src/helpers/DeviceDiag.cpp
@@ -24,6 +24,25 @@ uint32_t DeviceDiag::getStackFreeBytes() {
   return (uint32_t)uxTaskGetStackHighWaterMark(NULL) * sizeof(StackType_t);
 }
 
+#elif defined(ESP32)
+#include <freertos/FreeRTOS.h>
+#include <freertos/task.h>
+#include <esp_heap_caps.h>
+
+// MALLOC_CAP_8BIT: the general-purpose byte-addressable heap (what `new`/
+// malloc() actually draw from) -- excludes DMA-only/IRAM regions a plain
+// allocation could never land in, so this matches what's really available to
+// the rest of the firmware rather than overstating it with capability pools
+// nothing here can use.
+void DeviceDiag::getHeapStats(uint32_t& free_bytes, uint32_t& total_bytes) {
+  free_bytes  = (uint32_t)heap_caps_get_free_size(MALLOC_CAP_8BIT);
+  total_bytes = (uint32_t)heap_caps_get_total_size(MALLOC_CAP_8BIT);
+}
+
+uint32_t DeviceDiag::getStackFreeBytes() {
+  return (uint32_t)uxTaskGetStackHighWaterMark(NULL) * sizeof(StackType_t);
+}
+
 #else
 
 void DeviceDiag::getHeapStats(uint32_t& free_bytes, uint32_t& total_bytes) {