plog::Logger construction problem about plog HOT 4 CLOSED

Hi @mdevans

It's very interesting. Could you provide a complete code sample? Or at least describe when do you call plog::init and what compiler do you use?

from plog.

Thanks for your response @SergiusTheBest . I am using VS2015 C++ compiler. I am using the complex reflective dll injection technique as described by Dan Staples here: https://github.com/dismantl/ImprovedReflectiveDLLInjection. If you call plog::init within his "MyFunction()" (delayed dll init after dllmain()) the problem occurs. If I use standard injection technique using LoadLibrary() and CreateRemoteThread() plog::init works ok. I expect there is something in the way the image is loaded by ReflectiveLoader() which is omitting some critical init code? (nUserdataLen is 0 within MyFunction, a bug I haven't tracked down yet).

#include "ReflectiveLoader.h"
#include <stdio.h>
#include "plog\Log.h"

extern "C" DLLEXPORT BOOL
MyFunction(LPVOID lpUserdata, DWORD nUserdataLen)
{
    LPSTR str = (LPSTR)malloc(80 + nUserdataLen);

    sprintf_s(str, 80 + nUserdataLen, "Hello from MyFunction: %s!", (char*)lpUserdata);
    MessageBoxA(NULL, str, (LPCSTR)lpUserdata, MB_OK);

    plog::init(plog::verbose, "MDETEST.LOG"); 

    if (!plog::get<0>())
        OutputDebugString(L"Nope");
    else
        OutputDebugString(L"Yes");

    free(str);
    return TRUE;
}

from plog.

I did a little research and found out:

1. VS2015 implements thread-safe static variables initialization with the help of a thread-local storage (TLS).
2. ReflectiveLoader doesn't process TLS callbacks in the DLL image.

As the result constructors of static variables are not called.

Workaround: Use /Zc:threadSafeInit- compiler switch to turn off thread-safe static variables initialization.

from plog.

Fascinating... thank-you very much Sergius, makes complete sense now. (switch works btw)

from plog.