From b90c15eab49a054eead6e7846617c1024db1f599 Mon Sep 17 00:00:00 2001
From: shweet <email@shweetz.net>
Date: Wed, 14 Jan 2026 19:25:12 -0500
Subject: [PATCH] bring back windows dumps

---
 src/loader.cpp | 75 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 75 insertions(+)

diff --git a/src/loader.cpp b/src/loader.cpp
index 3198a95..4db094a 100644
--- a/src/loader.cpp
+++ b/src/loader.cpp
@@ -37,6 +37,77 @@ namespace anm2ed
   constexpr int SOCKET_ERROR_ADDRESS_IN_USE = EADDRINUSE;
 #endif
 
+#ifdef _WIN32
+  std::filesystem::path g_minidump_dir{};
+  PVOID g_vectored_handler{};
+  LONG g_dump_in_progress{};
+
+  void windows_minidump_write(EXCEPTION_POINTERS* exceptionPointers)
+  {
+    if (g_minidump_dir.empty()) return;
+    if (InterlockedExchange(&g_dump_in_progress, 1) != 0) return;
+
+    SYSTEMTIME st{};
+    GetLocalTime(&st);
+
+    auto pid = GetCurrentProcessId();
+    auto code = exceptionPointers && exceptionPointers->ExceptionRecord
+                    ? exceptionPointers->ExceptionRecord->ExceptionCode
+                    : 0u;
+
+    auto filename = std::format("anm2ed_{:04}{:02}{:02}_{:02}{:02}{:02}_pid{:08x}_code{:08x}.dmp", st.wYear, st.wMonth,
+                                st.wDay, st.wHour, st.wMinute, st.wSecond, pid, code);
+    auto dumpPath = g_minidump_dir / path::from_utf8(filename);
+
+    auto dumpPathW = dumpPath.wstring();
+    HANDLE file = CreateFileW(dumpPathW.c_str(), GENERIC_WRITE, FILE_SHARE_READ, nullptr, CREATE_ALWAYS,
+                              FILE_ATTRIBUTE_NORMAL, nullptr);
+    if (file == INVALID_HANDLE_VALUE) return;
+
+    MINIDUMP_EXCEPTION_INFORMATION mei{};
+    mei.ThreadId = GetCurrentThreadId();
+    mei.ExceptionPointers = exceptionPointers;
+    mei.ClientPointers = FALSE;
+
+    const MINIDUMP_TYPE dumpType = static_cast<MINIDUMP_TYPE>(MiniDumpNormal | MiniDumpWithIndirectlyReferencedMemory |
+                                                              MiniDumpWithThreadInfo | MiniDumpWithUnloadedModules);
+    MiniDumpWriteDump(GetCurrentProcess(), pid, file, dumpType, exceptionPointers ? &mei : nullptr, nullptr, nullptr);
+
+    FlushFileBuffers(file);
+    CloseHandle(file);
+  }
+
+  LONG WINAPI windows_unhandled_exception_filter(EXCEPTION_POINTERS* exceptionPointers)
+  {
+    windows_minidump_write(exceptionPointers);
+    return EXCEPTION_EXECUTE_HANDLER;
+  }
+
+  LONG CALLBACK windows_vectored_exception_handler(EXCEPTION_POINTERS* exceptionPointers)
+  {
+    windows_minidump_write(exceptionPointers);
+    return EXCEPTION_CONTINUE_SEARCH;
+  }
+
+  void windows_minidumps_configure()
+  {
+    auto prefDir = sdl::preferences_directory_get();
+    if (prefDir.empty()) return;
+
+    std::error_code ec{};
+    auto dumpDir = prefDir / "crash";
+    std::filesystem::create_directories(dumpDir, ec);
+    if (ec) return;
+
+    g_minidump_dir = dumpDir;
+
+    if (!g_vectored_handler) g_vectored_handler = AddVectoredExceptionHandler(1, windows_vectored_exception_handler);
+    SetUnhandledExceptionFilter(windows_unhandled_exception_filter);
+
+    logger.info(std::format("MiniDumpWriteDump enabled: {}", path::to_utf8(dumpDir)));
+  }
+#endif
+
   bool socket_paths_send(Socket& socket, const std::vector<std::string>& paths)
   {
     uint32_t count = htonl(static_cast<uint32_t>(paths.size()));
@@ -135,6 +206,10 @@ namespace anm2ed
 
     logger.info("Initialized SDL");
 
+#ifdef _WIN32
+    windows_minidumps_configure();
+#endif
+
     auto windowProperties = SDL_CreateProperties();
 
     if (windowProperties == 0)