Warning for shared external code during build (#1881)

firmware/tools/check_for_shared_external_code.py

@@ -0,0 +1,53 @@
+#!/usr/bin/env python3
+
+#
+# Copyright (C) 2024 Mark Thompson
+#
+# This file is part of PortaPack.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2, or (at your option)
+# any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; see the file COPYING.  If not, write to
+# the Free Software Foundation, Inc., 51 Franklin Street,
+# Boston, MA 02110-1301, USA.
+#
+
+import sys
+from external_app_info import maximum_application_size
+from external_app_info import external_apps_address_start
+from external_app_info import external_apps_address_end
+
+usage_message = """
+PortaPack ROM image checker for possible shared external code addresses
+
+Usage: <command> <input-file>
+"""
+
+def read_image(path):
+	f = open(path, 'rb')
+	data = f.read()
+	f.close()
+	return data
+
+if len(sys.argv) != 2:
+	print(usage_message)
+	sys.exit(-1)
+
+image = read_image(sys.argv[1])
+image = bytearray(image)
+
+for i in range(0, len(image), 4):
+	snippet = image[i:i+4]
+	val = int.from_bytes(snippet, byteorder='little')
+	offset = val & 0xFFFF
+	if (val >= external_apps_address_start) and (val < external_apps_address_end) and ((val & 0xFFFF) < maximum_application_size) and ((val & 0x3)==0):
+		print ("External code address", hex(val),"at offset", hex(i),"in", sys.argv[1])