commit 4a98dfd0520f15ddcd5ac181991ef5c79b4943cb
from: Aleksey Ryndin <continue@to.any-key.press>
date: Thu Mar 07 10:35:31 2024 UTC

Add checksum calculation

commit - 047062a2f005cb2382e7ab336c79e084f4dc6567
commit + 4a98dfd0520f15ddcd5ac181991ef5c79b4943cb
blob - 04e7a99f6764824e1494ae9bc5c2eefef0084bff
blob + a9886f3fdc8a849b5c7fe45d3bbfd3408023fe38
--- tools/img_eGON.BT0/img_eGON.BT0.cc
+++ tools/img_eGON.BT0/img_eGON.BT0.cc
@@ -8,12 +8,13 @@
 #include <memory>
 #include <array>
 #include <algorithm>
+#include <vector>
 
+
 namespace
 {
 
 
-
  /** Non-copiable objects */
 struct NonCopiable
 {
@@ -186,11 +187,48 @@ bool validate_and_dump(const char *image_file_path)
     std::cout << "+0x0C Checksum         : 0x" 
               << std::hex << std::setw(8) << std::setfill('0') 
               << header.m_checksum << std::endl;
+
+    const bool length_expected = 
+        (header.m_length > sizeof(header)) && (header.m_length & 511) == 0;
+    if (ret_value && length_expected)
+    {
+        const auto saved_checksum{header.m_checksum};
+        header.m_checksum = 0x5f0a6c39;
+
+        uint32_t checksum = 0;
+        for (uint32_t i = 0; i < sizeof(header) / sizeof(uint32_t); ++i)
+            checksum += reinterpret_cast<const uint32_t *>(&header)[i];
+
+        const uint32_t buff_size = header.m_length - sizeof(header);
+        std::vector<uint8_t> buff;
+        buff.resize(buff_size);
+        if (read(image_file.get(), &buff[0], buff_size) == buff_size)
+        {
+            for (uint32_t i = 0; i < buff_size / sizeof(uint32_t); ++i)
+                checksum += reinterpret_cast<const uint32_t *>(&buff[0])[i];
+            if (checksum == saved_checksum)
+            {
+                std::cout << "                         (v) OK" << std::endl;
+            }
+            else
+            {
+                ret_value = false;
+            }
+        }
+        else
+        {
+            ret_value = false;
+        }
+    }
+    else
+    {
+        ret_value = false;
+    }
 
     std::cout << "+0x10 Length           : 0x" 
               << std::hex << std::setw(8) << std::setfill('0') << header.m_length
               << ", " << std::dec << header.m_length << std::endl;
-    if ((header.m_length & 511) == 0)
+    if (length_expected)
     {
         std::cout << "                         (v) OK" << std::endl;
     }