path: root/src/VBox/Main/glue/initterm.cpp

/* $Id: initterm.cpp $ */
/** @file
 * MS COM / XPCOM Abstraction Layer - Initialization and Termination.
 */

/*
 * Copyright (C) 2006-2023 Oracle and/or its affiliates.
 *
 * This file is part of VirtualBox base platform packages, as
 * available from https://www.virtualbox.org.
 *
 * 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, in version 3 of the
 * License.
 *
 * 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; if not, see <https://www.gnu.org/licenses>.
 *
 * SPDX-License-Identifier: GPL-3.0-only
 */

#define LOG_GROUP LOG_GROUP_MAIN
#if !defined(VBOX_WITH_XPCOM)

# if !defined(_WIN32_WINNT) || _WIN32_WINNT < 0x600
#  undef  _WIN32_WINNT
#  define _WIN32_WINNT 0x600 /* GetModuleHandleExW */
# endif
# include <iprt/nt/nt-and-windows.h>
# include <iprt/win/objbase.h>
# include <iprt/win/rpcproxy.h>
# include <rpcasync.h>

#else /* !defined(VBOX_WITH_XPCOM) */

# include <stdlib.h>

# include <nsIComponentRegistrar.h>
# include <nsIServiceManager.h>
# include <nsCOMPtr.h>
# include <nsEventQueueUtils.h>
# include <nsEmbedString.h>

# include <nsILocalFile.h>
# include <nsIDirectoryService.h>
# include <nsDirectoryServiceDefs.h>

#endif /* !defined(VBOX_WITH_XPCOM) */

#include "VBox/com/com.h"
#include "VBox/com/assert.h"
#include "VBox/com/NativeEventQueue.h"
#include "VBox/com/AutoLock.h"

#include "../include/LoggingNew.h"

#include <iprt/asm.h>
#include <iprt/env.h>
#include <iprt/ldr.h>
#include <iprt/param.h>
#include <iprt/path.h>
#include <iprt/string.h>
#include <iprt/system.h>
#include <iprt/thread.h>

#include <VBox/err.h>

namespace com
{

#if defined(VBOX_WITH_XPCOM)

class DirectoryServiceProvider : public nsIDirectoryServiceProvider
{
public:

    NS_DECL_ISUPPORTS

    DirectoryServiceProvider()
        : mCompRegLocation(NULL), mXPTIDatLocation(NULL)
        , mComponentDirLocation(NULL), mCurrProcDirLocation(NULL)
        {}

    virtual ~DirectoryServiceProvider();

    HRESULT init(const char *aCompRegLocation,
                 const char *aXPTIDatLocation,
                 const char *aComponentDirLocation,
                 const char *aCurrProcDirLocation);

    NS_DECL_NSIDIRECTORYSERVICEPROVIDER

private:
    /** @remarks This is not a UTF-8 string. */
    char *mCompRegLocation;
    /** @remarks This is not a UTF-8 string. */
    char *mXPTIDatLocation;
    /** @remarks This is not a UTF-8 string. */
    char *mComponentDirLocation;
    /** @remarks This is not a UTF-8 string. */
    char *mCurrProcDirLocation;
};

NS_IMPL_ISUPPORTS1(DirectoryServiceProvider, nsIDirectoryServiceProvider)

DirectoryServiceProvider::~DirectoryServiceProvider()
{
    if (mCompRegLocation)
    {
        RTStrFree(mCompRegLocation);
        mCompRegLocation = NULL;
    }
    if (mXPTIDatLocation)
    {
        RTStrFree(mXPTIDatLocation);
        mXPTIDatLocation = NULL;
    }
    if (mComponentDirLocation)
    {
        RTStrFree(mComponentDirLocation);
        mComponentDirLocation = NULL;
    }
    if (mCurrProcDirLocation)
    {
        RTStrFree(mCurrProcDirLocation);
        mCurrProcDirLocation = NULL;
    }
}

/**
 *  @param aCompRegLocation Path to compreg.dat, in Utf8.
 *  @param aXPTIDatLocation Path to xpti.data, in Utf8.
 */
HRESULT
DirectoryServiceProvider::init(const char *aCompRegLocation,
                               const char *aXPTIDatLocation,
                               const char *aComponentDirLocation,
                               const char *aCurrProcDirLocation)
{
    AssertReturn(aCompRegLocation, NS_ERROR_INVALID_ARG);
    AssertReturn(aXPTIDatLocation, NS_ERROR_INVALID_ARG);

/** @todo r=bird: Gotta check how this encoding stuff plays out on darwin!
 *  We get down to [VBoxNsxp]NS_NewNativeLocalFile and that file isn't
 *  nsLocalFileUnix.cpp on 32-bit darwin.  On 64-bit darwin it's a question
 *  of what we're doing in IPRT and such...  We should probably add a
 *  RTPathConvertToNative for use here. */
    int vrc = RTStrUtf8ToCurrentCP(&mCompRegLocation, aCompRegLocation);
    if (RT_SUCCESS(vrc))
        vrc = RTStrUtf8ToCurrentCP(&mXPTIDatLocation, aXPTIDatLocation);
    if (RT_SUCCESS(vrc) && aComponentDirLocation)
        vrc = RTStrUtf8ToCurrentCP(&mComponentDirLocation, aComponentDirLocation);
    if (RT_SUCCESS(vrc) && aCurrProcDirLocation)
        vrc = RTStrUtf8ToCurrentCP(&mCurrProcDirLocation, aCurrProcDirLocation);

    return RT_SUCCESS(vrc) ? NS_OK : NS_ERROR_OUT_OF_MEMORY;
}

NS_IMETHODIMP
DirectoryServiceProvider::GetFile(const char *aProp,
                                  PRBool *aPersistent,
                                  nsIFile **aRetval)
{
    nsCOMPtr <nsILocalFile> localFile;
    nsresult rv = NS_ERROR_FAILURE;

    *aRetval = nsnull;
    *aPersistent = PR_TRUE;

    const char *fileLocation = NULL;

    if (strcmp(aProp, NS_XPCOM_COMPONENT_REGISTRY_FILE) == 0)
        fileLocation = mCompRegLocation;
    else if (strcmp(aProp, NS_XPCOM_XPTI_REGISTRY_FILE) == 0)
        fileLocation = mXPTIDatLocation;
    else if (mComponentDirLocation && strcmp(aProp, NS_XPCOM_COMPONENT_DIR) == 0)
        fileLocation = mComponentDirLocation;
    else if (mCurrProcDirLocation && strcmp(aProp, NS_XPCOM_CURRENT_PROCESS_DIR) == 0)
        fileLocation = mCurrProcDirLocation;
    else
        return NS_ERROR_FAILURE;

    rv = NS_NewNativeLocalFile(nsEmbedCString(fileLocation),
                               PR_TRUE, getter_AddRefs(localFile));
    if (NS_FAILED(rv))
        return rv;

    return localFile->QueryInterface(NS_GET_IID(nsIFile), (void **)aRetval);
}

/**
 *  Global XPCOM initialization flag (we maintain it ourselves since XPCOM
 *  doesn't provide such functionality)
 */
static bool volatile gIsXPCOMInitialized = false;

/**
 *  Number of Initialize() calls on the main thread.
 */
static unsigned int gXPCOMInitCount = 0;

#else /* !defined(VBOX_WITH_XPCOM) */

/**
 * Replacement function for the InvokeStub method for the IRundown stub.
 */
static HRESULT STDMETHODCALLTYPE
Rundown_InvokeStub(IRpcStubBuffer *pThis, RPCOLEMESSAGE *pMsg, IRpcChannelBuffer *pBuf) RT_NOTHROW_DEF
{
    /*
     * Our mission here is to prevent remote calls to methods #8 and #9,
     * as these contain raw pointers to callback functions.
     *
     * Note! APIs like I_RpcServerInqTransportType, I_RpcBindingInqLocalClientPID
     *       and RpcServerInqCallAttributesW are not usable in this context without
     *       a rpc binding handle (latter two).
     *
     * P.S.  In more recent windows versions, the buffer implements a interface
     *       IID_IRpcChannelBufferMarshalingContext (undocumented) which has a
     *       GetIMarshallingContextAttribute() method that will return the client PID
     *       when asking for attribute #0x8000000e.
     */
    uint32_t const iMethod = pMsg->iMethod & 0xffff; /* Uncertain, but there are hints that the upper bits are flags. */
    HRESULT        hrc;
    if (   (   iMethod != 8
            && iMethod != 9)
        || (pMsg->rpcFlags & RPCFLG_LOCAL_CALL) )
        hrc = CStdStubBuffer_Invoke(pThis, pMsg, pBuf);
    else
    {
        LogRel(("Rundown_InvokeStub: Rejected call to CRundown::%s: rpcFlags=%#x cbBuffer=%#x dataRepresentation=%d buffer=%p:{%.*Rhxs} reserved1=%p reserved2={%p,%p,%p,%p,%p}\n",
                pMsg->iMethod == 8 ? "DoCallback" : "DoNonreentrantCallback", pMsg->rpcFlags, pMsg->cbBuffer,
                pMsg->dataRepresentation, pMsg->Buffer, RT_VALID_PTR(pMsg->Buffer) ? pMsg->cbBuffer : 0, pMsg->Buffer,
                pMsg->reserved1, pMsg->reserved2[0], pMsg->reserved2[1], pMsg->reserved2[2], pMsg->reserved2[3], pMsg->reserved2[4]));
        hrc = E_ACCESSDENIED;
    }
    return hrc;
}

/**
 * Replacement function for the InvokeStub method for the IDLLHost stub.
 */
static HRESULT STDMETHODCALLTYPE
DLLHost_InvokeStub(IRpcStubBuffer *pThis, RPCOLEMESSAGE *pMsg, IRpcChannelBuffer *pBuf) RT_NOTHROW_DEF
{
    /*
     * Our mission here is to prevent remote calls to this interface as method #3
     * contain a raw pointer an DllGetClassObject function.  There are only that
     * method in addition to the IUnknown stuff, and it's ASSUMED that it's
     * process internal only (cross apartment stuff).
     */
    uint32_t const iMethod = pMsg->iMethod & 0xffff; /* Uncertain, but there are hints that the upper bits are flags. */
    HRESULT        hrc;
    if (pMsg->rpcFlags & RPCFLG_LOCAL_CALL)
        hrc = CStdStubBuffer_Invoke(pThis, pMsg, pBuf);
    else
    {
        LogRel(("DLLHost_InvokeStub: Rejected call to CDLLHost::%s: rpcFlags=%#x cbBuffer=%#x dataRepresentation=%d buffer=%p:{%.*Rhxs} reserved1=%p reserved2={%p,%p,%p,%p,%p}\n",
                pMsg->iMethod == 0 ? "QueryInterface" :
                pMsg->iMethod == 1 ? "AddRef" :
                pMsg->iMethod == 2 ? "ReleaseRef" :
                pMsg->iMethod == 3 ? "DllGetClassObject" : "Unknown", pMsg->rpcFlags, pMsg->cbBuffer,
                pMsg->dataRepresentation, pMsg->Buffer, RT_VALID_PTR(pMsg->Buffer) ? pMsg->cbBuffer : 0, pMsg->Buffer,
                pMsg->reserved1, pMsg->reserved2[0], pMsg->reserved2[1], pMsg->reserved2[2], pMsg->reserved2[3], pMsg->reserved2[4]));
        hrc = E_ACCESSDENIED;
    }
    return hrc;
}

/**
 * Replaces the IRundown InvokeStub method with Rundown_InvokeStub so we can
 * reject remote calls to a couple of misdesigned methods.
 *
 * Also replaces the IDLLHost for the same reasons.
 */
void PatchComBugs(void)
{
    static volatile bool s_fPatched = false;
    if (s_fPatched)
        return;

    /*
     * The combase.dll / ole32.dll is exporting a DllGetClassObject function
     * that is implemented using NdrDllGetClassObject just like our own
     * proxy/stub DLL.  This means we can get at the stub interface lists,
     * since what NdrDllGetClassObject has CStdPSFactoryBuffer as layout.
     *
     * Note! Tried using CoRegisterPSClsid instead of this mess, but no luck.
     */
    /* Locate the COM DLL, it must be loaded by now: */
    HMODULE hmod = GetModuleHandleW(L"COMBASE.DLL");
    if (!hmod)
        hmod = GetModuleHandleW(L"OLE32.DLL"); /* w7 */
    AssertReturnVoid(hmod != NULL);

    /* Resolve the class getter: */
    LPFNGETCLASSOBJECT pfnGetClassObject = (LPFNGETCLASSOBJECT)GetProcAddress(hmod, "DllGetClassObject");
    AssertReturnVoid(pfnGetClassObject != NULL);

    /* Get the factory instance: */
    static const CLSID   s_PSOlePrx32ClsId = {0x00000320,0x0000,0x0000,{0xc0,0x00,0x00,0x00,0x00,0x00,0x00,0x46}};
    CStdPSFactoryBuffer *pFactoryBuffer = NULL;
    HRESULT hrc = pfnGetClassObject(s_PSOlePrx32ClsId, IID_IPSFactoryBuffer, (void **)&pFactoryBuffer);
    AssertMsgReturnVoid(SUCCEEDED(hrc),  ("hrc=%Rhrc\n",  hrc));
    AssertReturnVoid(pFactoryBuffer != NULL);

    /*
     * Search thru the file list for the interface we want to patch.
     */
    static const IID s_IID_Rundown = {0x00000134,0x0000,0x0000,{0xc0,0x00,0x00,0x00,0x00,0x00,0x00,0x46}};
    static const IID s_IID_DLLHost = {0x00000141,0x0000,0x0000,{0xc0,0x00,0x00,0x00,0x00,0x00,0x00,0x46}};
    decltype(CStdStubBuffer_Invoke) *pfnInvoke = (decltype(pfnInvoke))GetProcAddress(hmod, "CStdStubBuffer_Invoke");
    if (!pfnInvoke)
        pfnInvoke = (decltype(pfnInvoke))GetProcAddress(GetModuleHandleW(L"RPCRT4.DLL"), "CStdStubBuffer_Invoke");

    unsigned cPatched = 0;
    unsigned cAlreadyPatched = 0;
    Assert(pFactoryBuffer->pProxyFileList != NULL);
    for (ProxyFileInfo const **ppCur = pFactoryBuffer->pProxyFileList; *ppCur != NULL; ppCur++)
    {
        ProxyFileInfo const *pCur = *ppCur;

        if (pCur->pStubVtblList)
        {
            for (PCInterfaceStubVtblList const *ppCurStub = pCur->pStubVtblList; *ppCurStub != NULL; ppCurStub++)
            {
                PCInterfaceStubVtblList const pCurStub = *ppCurStub;
                IID const *piid = pCurStub->header.piid;
                if (piid)
                {
                    if (IsEqualIID(*piid, s_IID_Rundown))
                    {
                        if (pCurStub->Vtbl.Invoke == pfnInvoke)
                        {
                            DWORD fOld = 0;
                            if (VirtualProtect(&pCurStub->Vtbl.Invoke, sizeof(pCurStub->Vtbl.Invoke), PAGE_READWRITE, &fOld))
                            {
                                pCurStub->Vtbl.Invoke = Rundown_InvokeStub;
                                VirtualProtect(&pCurStub->Vtbl.Invoke, sizeof(pCurStub->Vtbl.Invoke), fOld, &fOld);
                                cPatched++;
                            }
                            else
                                AssertMsgFailed(("%d\n", GetLastError()));
                        }
                        else
                            cAlreadyPatched++;
                    }
                    else if (IsEqualIID(*piid, s_IID_DLLHost))
                    {
                        if (pCurStub->Vtbl.Invoke == pfnInvoke)
                        {
                            DWORD fOld = 0;
                            if (VirtualProtect(&pCurStub->Vtbl.Invoke, sizeof(pCurStub->Vtbl.Invoke), PAGE_READWRITE, &fOld))
                            {
                                pCurStub->Vtbl.Invoke = DLLHost_InvokeStub;
                                VirtualProtect(&pCurStub->Vtbl.Invoke, sizeof(pCurStub->Vtbl.Invoke), fOld, &fOld);
                                cPatched++;
                            }
                            else
                                AssertMsgFailed(("%d\n", GetLastError()));
                        }
                        else
                            cAlreadyPatched++;
                    }
                }
            }
       }
    }

    /* done */
    pFactoryBuffer->lpVtbl->Release((IPSFactoryBuffer *)pFactoryBuffer);

    /*
     * If we patched anything we should try prevent being unloaded.
     */
    if (cPatched > 0)
    {
        s_fPatched = true;
        HMODULE hmodSelf;
        AssertLogRelMsg(GetModuleHandleExW(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS | GET_MODULE_HANDLE_EX_FLAG_PIN,
                                           (LPCWSTR)(uintptr_t)Rundown_InvokeStub, &hmodSelf),
                        ("last error: %u; Rundown_InvokeStub=%p\n", GetLastError(), Rundown_InvokeStub));
    }
    AssertLogRelMsg(cAlreadyPatched + cPatched >= 2,
                    ("COM patching of IRundown/IDLLHost failed! (%d+%d)\n", cAlreadyPatched, cPatched));
}


/**
 *  The COM main thread handle. (The first caller of com::Initialize().)
 */
static RTTHREAD volatile gCOMMainThread = NIL_RTTHREAD;

/**
 *  Number of Initialize() calls on the main thread.
 */
static uint32_t gCOMMainInitCount = 0;

#endif /* !defined(VBOX_WITH_XPCOM) */


/**
 * Initializes the COM runtime.
 *
 * This method must be called on each thread of the client application that
 * wants to access COM facilities. The initialization must be performed before
 * calling any other COM method or attempting to instantiate COM objects.
 *
 * On platforms using XPCOM, this method uses the following scheme to search for
 * XPCOM runtime:
 *
 * 1. If the VBOX_APP_HOME environment variable is set, the path it specifies
 *    is used to search XPCOM libraries and components. If this method fails to
 *    initialize XPCOM runtime using this path, it will immediately return a
 *    failure and will NOT check for other paths as described below.
 *
 * 2. If VBOX_APP_HOME is not set, this methods tries the following paths in the
 *    given order:
 *
 *    a) Compiled-in application data directory (as returned by
 *       RTPathAppPrivateArch())
 *    b) "/usr/lib/virtualbox" (Linux only)
 *    c) "/opt/VirtualBox" (Linux only)
 *
 *    The first path for which the initialization succeeds will be used.
 *
 * On MS COM platforms, the COM runtime is provided by the system and does not
 * need to be searched for.
 *
 * Once the COM subsystem is no longer necessary on a given thread, Shutdown()
 * must be called to free resources allocated for it. Note that a thread may
 * call Initialize() several times but for each of tese calls there must be a
 * corresponding Shutdown() call.
 *
 * @return S_OK on success and a COM result code in case of failure.
 */
HRESULT Initialize(uint32_t fInitFlags /*=VBOX_COM_INIT_F_DEFAULT*/)
{
    HRESULT hrc = E_FAIL;

#if !defined(VBOX_WITH_XPCOM)

# ifdef VBOX_WITH_AUTO_COM_REG_UPDATE
    /*
     * First time we're called in a process, we refresh the VBox COM
     * registrations.   Use a global mutex to prevent updating when there are
     * API users already active, as that could lead to a bit of a mess.
     */
    if (   (fInitFlags & VBOX_COM_INIT_F_AUTO_REG_UPDATE)
        && gCOMMainThread == NIL_RTTHREAD)
    {
        SetLastError(ERROR_SUCCESS);
        HANDLE hLeakIt = CreateMutexW(NULL/*pSecAttr*/, FALSE, L"Global\\VirtualBoxComLazyRegistrationMutant");
        DWORD  dwErr   = GetLastError();
        AssertMsg(dwErr == ERROR_SUCCESS || dwErr == ERROR_ALREADY_EXISTS || dwErr == ERROR_ACCESS_DENIED, ("%u\n", dwErr));
        if (dwErr == ERROR_SUCCESS)
        {
            char szPath[RTPATH_MAX];
            int vrc = RTPathAppPrivateArch(szPath, sizeof(szPath));
            if (RT_SUCCESS(vrc))
#  ifndef VBOX_IN_32_ON_64_MAIN_API
                vrc = RTPathAppend(szPath, sizeof(szPath),
                                      RT_MAKE_U64(((PKUSER_SHARED_DATA)MM_SHARED_USER_DATA_VA)->NtMinorVersion,
                                                  ((PKUSER_SHARED_DATA)MM_SHARED_USER_DATA_VA)->NtMajorVersion)
                                   >= RT_MAKE_U64(1/*Lo*/,6/*Hi*/)
                                   ? "VBoxProxyStub.dll" : "VBoxProxyStubLegacy.dll");
#  else
                vrc = RTPathAppend(szPath, sizeof(szPath), "x86\\VBoxProxyStub-x86.dll");
#  endif
            if (RT_SUCCESS(vrc))
            {
                RTLDRMOD hMod;
                vrc = RTLdrLoad(szPath, &hMod);
                if (RT_SUCCESS(vrc))
                {
                    union
                    {
                        void *pv;
                        DECLCALLBACKMEMBER(uint32_t, pfnRegUpdate,(void));
                    } u;
                    vrc = RTLdrGetSymbol(hMod, "VbpsUpdateRegistrations", &u.pv);
                    if (RT_SUCCESS(vrc))
                        u.pfnRegUpdate();
                    /* Just keep it loaded. */
                }
            }
            Assert(hLeakIt != NULL); NOREF(hLeakIt);
        }
    }
# endif

    /*
     * We initialize COM in GUI thread in STA, to be compliant with QT and
     * OLE requirments (for example to allow D&D), while other threads
     * initialized in regular MTA. To allow fast proxyless access from
     * GUI thread to COM objects, we explicitly provide our COM objects
     * with free threaded marshaller.
     * !!!!! Please think twice before touching this code !!!!!
     */
    DWORD flags = fInitFlags & VBOX_COM_INIT_F_GUI
                ?   COINIT_APARTMENTTHREADED
                  | COINIT_SPEED_OVER_MEMORY
                :   COINIT_MULTITHREADED
                  | COINIT_DISABLE_OLE1DDE
                  | COINIT_SPEED_OVER_MEMORY;

    hrc = CoInitializeEx(NULL, flags);

    /* the overall result must be either S_OK or S_FALSE (S_FALSE means
     * "already initialized using the same apartment model") */
    AssertMsg(hrc == S_OK || hrc == S_FALSE, ("hrc=%08X\n", hrc));

#if defined(VBOX_WITH_SDS)
    // Setup COM Security to enable impersonation
    HRESULT hrcGUICoInitializeSecurity = CoInitializeSecurity(NULL,
                                                              -1,
                                                              NULL,
                                                              NULL,
                                                              RPC_C_AUTHN_LEVEL_DEFAULT,
                                                              RPC_C_IMP_LEVEL_IMPERSONATE,
                                                              NULL,
                                                              EOAC_NONE,
                                                              NULL);
    NOREF(hrcGUICoInitializeSecurity);
    Assert(SUCCEEDED(hrcGUICoInitializeSecurity) || hrcGUICoInitializeSecurity == RPC_E_TOO_LATE);
#endif

    /*
     * IRundown has unsafe two methods we need to patch to prevent remote access.
     * Do that before we start using COM and open ourselves to possible attacks.
     */
    if (!(fInitFlags & VBOX_COM_INIT_F_NO_COM_PATCHING))
        PatchComBugs();

    /* To be flow compatible with the XPCOM case, we return here if this isn't
     * the main thread or if it isn't its first initialization call.
     * Note! CoInitializeEx and CoUninitialize does it's own reference
     *       counting, so this exercise is entirely for the EventQueue init. */
    bool fRc;
    RTTHREAD hSelf = RTThreadSelf();
    if (hSelf != NIL_RTTHREAD)
        ASMAtomicCmpXchgHandle(&gCOMMainThread, hSelf, NIL_RTTHREAD, fRc);
    else
        fRc = false;

    if (fInitFlags & VBOX_COM_INIT_F_GUI)
        Assert(RTThreadIsMain(hSelf));

    if (!fRc)
    {
        if (   gCOMMainThread == hSelf
            && SUCCEEDED(hrc))
            gCOMMainInitCount++;

        AssertComRC(hrc);
        return hrc;
    }
    Assert(RTThreadIsMain(hSelf));

    /* this is the first main thread initialization */
    Assert(gCOMMainInitCount == 0);
    if (SUCCEEDED(hrc))
        gCOMMainInitCount = 1;

#else /* !defined(VBOX_WITH_XPCOM) */

    /* Unused here */
    RT_NOREF(fInitFlags);

    if (ASMAtomicXchgBool(&gIsXPCOMInitialized, true) == true)
    {
        /* XPCOM is already initialized on the main thread, no special
         * initialization is necessary on additional threads. Just increase
         * the init counter if it's a main thread again (to correctly support
         * nested calls to Initialize()/Shutdown() for compatibility with
         * Win32). */

        nsCOMPtr<nsIEventQueue> eventQ;
        hrc = NS_GetMainEventQ(getter_AddRefs(eventQ));

        if (NS_SUCCEEDED(hrc))
        {
            PRBool isOnMainThread = PR_FALSE;
            hrc = eventQ->IsOnCurrentThread(&isOnMainThread);
            if (NS_SUCCEEDED(hrc) && isOnMainThread)
                ++gXPCOMInitCount;
        }

        AssertComRC(hrc);
        return hrc;
    }
    Assert(RTThreadIsMain(RTThreadSelf()));

    /* this is the first initialization */
    gXPCOMInitCount = 1;

    /* prepare paths for registry files */
    char szCompReg[RTPATH_MAX];
    char szXptiDat[RTPATH_MAX];

    int vrc = GetVBoxUserHomeDirectory(szCompReg, sizeof(szCompReg));
    if (vrc == VERR_ACCESS_DENIED)
        return NS_ERROR_FILE_ACCESS_DENIED;
    AssertRCReturn(vrc, NS_ERROR_FAILURE);
    vrc = RTStrCopy(szXptiDat, sizeof(szXptiDat), szCompReg);
    AssertRCReturn(vrc, NS_ERROR_FAILURE);
# ifdef VBOX_IN_32_ON_64_MAIN_API
    vrc = RTPathAppend(szCompReg, sizeof(szCompReg), "compreg-x86.dat");
    AssertRCReturn(vrc, NS_ERROR_FAILURE);
    vrc = RTPathAppend(szXptiDat, sizeof(szXptiDat), "xpti-x86.dat");
    AssertRCReturn(vrc, NS_ERROR_FAILURE);
# else
    vrc = RTPathAppend(szCompReg, sizeof(szCompReg), "compreg.dat");
    AssertRCReturn(vrc, NS_ERROR_FAILURE);
    vrc = RTPathAppend(szXptiDat, sizeof(szXptiDat), "xpti.dat");
    AssertRCReturn(vrc, NS_ERROR_FAILURE);
# endif

    LogFlowFunc(("component registry  : \"%s\"\n", szCompReg));
    LogFlowFunc(("XPTI data file      : \"%s\"\n", szXptiDat));

    static const char *kAppPathsToProbe[] =
    {
        NULL, /* 0: will use VBOX_APP_HOME */
        NULL, /* 1: will try RTPathAppPrivateArch(), correctly installed release builds will never go further */
        NULL, /* 2: will try parent directory of RTPathAppPrivateArch(), only for testcases in non-hardened builds */
        /* There used to be hard coded paths, but they only caused trouble
         * because they often led to mixing of builds or even versions.
         * If you feel tempted to add anything here, think again. They would
         * only be used if option 1 would not work, which is a sign of a big
         * problem, as it returns a fixed location defined at compile time.
         * It is better to fail than blindly trying to cover the problem. */
    };

    /* Find out the directory where VirtualBox binaries are located */
    for (size_t i = 0; i < RT_ELEMENTS(kAppPathsToProbe); ++ i)
    {
        char szAppHomeDir[RTPATH_MAX];

        if (i == 0)
        {
            /* Use VBOX_APP_HOME if present */
            vrc = RTEnvGetEx(RTENV_DEFAULT, "VBOX_APP_HOME", szAppHomeDir, sizeof(szAppHomeDir), NULL);
            if (vrc == VERR_ENV_VAR_NOT_FOUND)
                continue;
            AssertRC(vrc);
        }
        else if (i == 1)
        {
            /* Use RTPathAppPrivateArch() first */
            vrc = RTPathAppPrivateArch(szAppHomeDir, sizeof(szAppHomeDir));
            AssertRC(vrc);
        }
        else if (i == 2)
        {
# ifdef VBOX_WITH_HARDENING
            continue;
# else /* !VBOX_WITH_HARDENING */
            /* Use parent of RTPathAppPrivateArch() if ends with "testcase" */
            vrc = RTPathAppPrivateArch(szAppHomeDir, sizeof(szAppHomeDir));
            AssertRC(vrc);
            vrc = RTPathStripTrailingSlash(szAppHomeDir);
            AssertRC(vrc);
            char *filename = RTPathFilename(szAppHomeDir);
            if (!filename || strcmp(filename, "testcase"))
                continue;
            RTPathStripFilename(szAppHomeDir);
# endif /* !VBOX_WITH_HARDENING */
        }
        else
        {
            /* Iterate over all other paths */
            RTStrCopy(szAppHomeDir, sizeof(szAppHomeDir), kAppPathsToProbe[i]);
            vrc = VINF_SUCCESS;
        }
        if (RT_FAILURE(vrc))
        {
            hrc = NS_ERROR_FAILURE;
            continue;
        }
        char szCompDir[RTPATH_MAX];
        vrc = RTStrCopy(szCompDir, sizeof(szCompDir), szAppHomeDir);
        if (RT_FAILURE(vrc))
        {
            hrc = NS_ERROR_FAILURE;
            continue;
        }
        vrc = RTPathAppend(szCompDir, sizeof(szCompDir), "components");
        if (RT_FAILURE(vrc))
        {
            hrc = NS_ERROR_FAILURE;
            continue;
        }
        LogFlowFunc(("component directory : \"%s\"\n", szCompDir));

        nsCOMPtr<DirectoryServiceProvider> dsProv;
        dsProv = new DirectoryServiceProvider();
        if (dsProv)
            hrc = dsProv->init(szCompReg, szXptiDat, szCompDir, szAppHomeDir);
        else
            hrc = NS_ERROR_OUT_OF_MEMORY;
        if (NS_FAILED(hrc))
            break;

        /* Setup the application path for NS_InitXPCOM2. Note that we properly
         * answer the NS_XPCOM_CURRENT_PROCESS_DIR query in our directory
         * service provider but it seems to be activated after the directory
         * service is used for the first time (see the source NS_InitXPCOM2). So
         * use the same value here to be on the safe side. */
        nsCOMPtr <nsIFile> appDir;
        {
            char *appDirCP = NULL;
            vrc = RTStrUtf8ToCurrentCP(&appDirCP, szAppHomeDir);
            if (RT_SUCCESS(vrc))
            {
                nsCOMPtr<nsILocalFile> file;
                hrc = NS_NewNativeLocalFile(nsEmbedCString(appDirCP), PR_FALSE, getter_AddRefs(file));
                if (NS_SUCCEEDED(hrc))
                    appDir = do_QueryInterface(file, &hrc);

                RTStrFree(appDirCP);
            }
            else
                hrc = NS_ERROR_FAILURE;
        }
        if (NS_FAILED(hrc))
            break;

        /* Set VBOX_XPCOM_HOME to the same app path to make XPCOM sources that
         * still use it instead of the directory service happy */
        vrc = RTEnvSetEx(RTENV_DEFAULT, "VBOX_XPCOM_HOME", szAppHomeDir);
        AssertRC(vrc);

        /* Finally, initialize XPCOM */
        {
            nsCOMPtr<nsIServiceManager> serviceManager;
            hrc = NS_InitXPCOM2(getter_AddRefs(serviceManager), appDir, dsProv);
            if (NS_SUCCEEDED(hrc))
            {
                nsCOMPtr<nsIComponentRegistrar> registrar = do_QueryInterface(serviceManager, &hrc);
                if (NS_SUCCEEDED(hrc))
                {
                    hrc = registrar->AutoRegister(nsnull);
                    if (NS_SUCCEEDED(hrc))
                    {
                        /* We succeeded, stop probing paths */
                        LogFlowFunc(("Succeeded.\n"));
                        break;
                    }
                }
            }
        }

        /* clean up before the new try */
        HRESULT hrc2 = NS_ShutdownXPCOM(nsnull);
        if (SUCCEEDED(hrc))
            hrc = hrc2;

        if (i == 0)
        {
            /* We failed with VBOX_APP_HOME, don't probe other paths */
            break;
        }
    }

#endif /* !defined(VBOX_WITH_XPCOM) */

    AssertComRCReturnRC(hrc);

    // for both COM and XPCOM, we only get here if this is the main thread;
    // only then initialize the autolock system (AutoLock.cpp)
    Assert(RTThreadIsMain(RTThreadSelf()));
    util::InitAutoLockSystem();

    /*
     * Init the main event queue (ASSUMES it cannot fail).
     */
    if (SUCCEEDED(hrc))
        NativeEventQueue::init();

    return hrc;
}

HRESULT Shutdown()
{
    HRESULT hrc = S_OK;

#if !defined(VBOX_WITH_XPCOM)

    /* EventQueue::uninit reference counting fun. */
    RTTHREAD hSelf = RTThreadSelf();
    if (    hSelf == gCOMMainThread
        &&  hSelf != NIL_RTTHREAD)
    {
        if (-- gCOMMainInitCount == 0)
        {
            NativeEventQueue::uninit();
            ASMAtomicWriteHandle(&gCOMMainThread, NIL_RTTHREAD);
        }
    }

    CoUninitialize();

#else /* !defined(VBOX_WITH_XPCOM) */

    nsCOMPtr<nsIEventQueue> eventQ;
    hrc = NS_GetMainEventQ(getter_AddRefs(eventQ));

    if (NS_SUCCEEDED(hrc) || hrc == NS_ERROR_NOT_AVAILABLE)
    {
        /* NS_ERROR_NOT_AVAILABLE seems to mean that
         * nsIEventQueue::StopAcceptingEvents() has been called (see
         * nsEventQueueService.cpp). We hope that this error code always means
         * just that in this case and assume that we're on the main thread
         * (it's a kind of unexpected behavior if a non-main thread ever calls
         * StopAcceptingEvents() on the main event queue). */

        PRBool isOnMainThread = PR_FALSE;
        if (NS_SUCCEEDED(hrc))
        {
            hrc = eventQ->IsOnCurrentThread(&isOnMainThread);
            eventQ = nsnull; /* early release before shutdown */
        }
        else
        {
            isOnMainThread = RTThreadIsMain(RTThreadSelf());
            hrc = NS_OK;
        }

        if (NS_SUCCEEDED(hrc) && isOnMainThread)
        {
            /* only the main thread needs to uninitialize XPCOM and only if
             * init counter drops to zero */
            if (--gXPCOMInitCount == 0)
            {
                NativeEventQueue::uninit();
                hrc = NS_ShutdownXPCOM(nsnull);

                /* This is a thread initialized XPCOM and set gIsXPCOMInitialized to
                 * true. Reset it back to false. */
                bool wasInited = ASMAtomicXchgBool(&gIsXPCOMInitialized, false);
                Assert(wasInited == true);
                NOREF(wasInited);
            }
        }
    }

#endif /* !defined(VBOX_WITH_XPCOM) */

    AssertComRC(hrc);

    return hrc;
}

} /* namespace com */