a fix for airstrike3D game crash for modern hardware. (a buffer overrun fix).

airstrike3d_fix.cpp

#define WIN32_LEAN_AND_MEAN
#include <Windows.h>
#include <stdio.h>

// compile with msvc or with mingw with -m32 flag; with target name as3dres.dll;
// rename original as3dres.dll to as3dre2.dll
// drop in the compiled dll into game folder.

void init_patch();

#ifdef _MSC_VER
#define FORWARDED_EXPORT(exp_name, target_name) __pragma (comment (linker, "/export:" #exp_name "=" #target_name))
#elif __MINGW32__
#define FORWARDED_EXPORT(exp_name, target_name) asm (".section .drectve\n\t.ascii \" -export:" #exp_name "= " #target_name "\"");
#endif

FORWARDED_EXPORT(DoMessage, as3dre2.DoMessage);

BOOL __stdcall DllMain(HMODULE hInstance, UINT_PTR ulReason, LPVOID pvReserved)
{
    switch (ulReason)
    {
    case DLL_PROCESS_ATTACH:
        init_patch();
        break;

    case DLL_PROCESS_DETACH:
    case DLL_THREAD_ATTACH:
    case DLL_THREAD_DETACH:
        break;
    }
    return TRUE;
}

bool write_memory(void* destination, const void* source, size_t size) {
    DWORD old_protection = 0;
    if (::VirtualProtect(destination, size, PAGE_READWRITE, &old_protection)) {
        ::memcpy(destination, source, size);
        DWORD throw_away = 0;
        return ::VirtualProtect(destination, size, old_protection, &throw_away);
    }
    return false;
}

bool write_jump(LONG From, LONG To)
{
    if ((To < (From + 128)) && (To > (From - 128))) {
        BYTE bpJump[2] = { 0xEB, BYTE((To - From) - 0x02) };
        return write_memory((void*)From, bpJump, 2);
    }

    BYTE bpJump[5] = { 0xE9, 0x00, 0x00, 0x00, 0x00 };
    *(DWORD*)&bpJump[1] = (To - From) - 5; //Calculate jump
    return write_memory((void*)From, bpJump, 5);
}

// return might be incorrect, but hey! it works!
void __cdecl write_log(const char* format_string, ...) {
    FILE* log = nullptr;
#ifdef _MSC_VER
    if (0 == ::fopen_s(&log, "astrike.log", "a+"))
#else
    if (log = fopen("astrike.log", "a+"))
#endif //
    {
        va_list arg_list;
        va_start(arg_list, format_string);
#ifndef _MSC_VER
        if (log) ::vfprintf(log, format_string, arg_list);
#else
        if (log) ::vfprintf_s(log, format_string, arg_list);
#endif
        if (log) ::fclose(log);
        va_end(arg_list);
    }
}

void init_patch()
{
    // another game version require another address
    // WriteJump(0x0041E0B0, (DWORD)write_log);

    write_jump(0x0040C280, (LONG)write_log);
}

I got this error (I'm compile it on Linux )

$ i686-w64-mingw32-g++ airstrike3d_fix.cpp -m32  -mwindows -o as3dres
/usr/lib/gcc/i686-w64-mingw32/12.1.0/../../../../i686-w64-mingw32/bin/ld: /usr/lib/gcc/i686-w64-mingw32/12.1.0/../../../../i686-w64-mingw32/lib/../lib/libmingw32.a(lib32_libmingw32_a-crt0_c.o): in function `main':
/build/mingw-w64-crt/src/mingw-w64-v10.0.0/mingw-w64-crt/crt/crt0_c.c:18: undefined reference to `WinMain@16'
collect2: error: ld returned 1 exit status

Hi, it need to be compiled as a dll, not as an executable. please append an extension to the output name.
Also this 'fix' is for GH (game house) version. Another version required another specific offset to patch.

Thanks for reply, actually I tried to compile it on Linux and looks it won't work, can you gave me hint how to compile it on Windows e.g. via MS Visual Studio 2015 .