From 234c5ea1705609f2744de9694d40b9295e8d8d0a Mon Sep 17 00:00:00 2001
From: Jason2866 <24528715+Jason2866@users.noreply.github.com>
Date: Mon, 17 Mar 2025 13:59:25 +0100
Subject: [PATCH] check fw size against partition (#23160)

---
 pio-tools/post_esp32.py | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/pio-tools/post_esp32.py b/pio-tools/post_esp32.py
index e986a5021..28066bf95 100644
--- a/pio-tools/post_esp32.py
+++ b/pio-tools/post_esp32.py
@@ -26,7 +26,7 @@ platform = env.PioPlatform()
 from genericpath import exists
 import os
 import sys
-from os.path import join
+from os.path import join, getsize
 import csv
 import requests
 import shutil
@@ -272,6 +272,13 @@ def esp32_create_combined_bin(source, target, env):
             "--flash_size",
             flash_size,
         ]
+        # platformio estimates the flash space used to store the firmware.
+        # the estimation is inaccurate. perform a final check on the firmware
+        # size by comparing it against the partition size.
+        max_size = env.BoardConfig().get("upload.maximum_size", 1)
+        fw_size = getsize(firmware_name)
+        if (fw_size > max_size):
+            raise Exception(Fore.RED + "firmware binary too large: %d > %d" % (fw_size, max_size))
 
         print("    Offset | File")
         for section in sections: