Сущность технологии СОМ. Библиотека программиста

// simultaneously)

void

StatementEnumerator::Lock(void)

{

EnterCriticalSection(&m_csLock);

m_pThis->SLock;

}

void

StatementEnumerator::Unlock(void)

{

LeaveCriticalSection(&m_csLock);

m_pThis->SUnlock;

}

// IUnknown methods

STDMETHODIMP

StatementEnumerator::QueryInterface(REFIID riid, void **ppv)

{

if (riid == IID_IUnknown)

*ppv = static_cast(this);

else if (riid == IID_IEnumString)

*ppv = static_cast(this);

else

return (*ppv = 0), E_NOINTERFACE;

reinterpret_cast(*ppv)->AddRef;

return S_OK;

}

STDMETHODIMP_(ULONG)

StatementEnumerator::AddRef(void)

{

return InterlockedIncrement(&m_cRef);

}

STDMETHODIMP_(ULONG)

StatementEnumerator::Release(void)

{

LONG res = InterlockedDecrement(&m_cRef);

if (res == 0)

delete this;

return res;

}

// IEnumString methods

STDMETHODIMP

StatementEnumerator::Next(ULONG cElems, OLECHAR **rgElems,

ULONG *pcFetched)

{

if (pcFetched == 0 && cElems > 1)

return E_INVALIDARG;

ZeroMemory(rgElems, sizeof(OLECHAR*) * cElems);

Lock;

ULONG cActual = 0;

while (cActual < cElems

&& m_cursor != m_pThis->m_statements.end)

{

if (rgElems[cActual] = OLESTRDUP((*m_cursor).c_str))

{

m_cursor++;

cActual++;

}

else // allocation error, unwind

{

while (cActual > 0)

{

cActual–;

CoTaskMemFree(rgElems[cActual]);

rgElems[cActual] = 0;

}

break;

}

}

Unlock;

if (pcFetched)

*pcFetched = cActual;

return cElems == cActual ? S_OK : S_FALSE;

}

STDMETHODIMP

StatementEnumerator::Skip(ULONG cElems)

{

Lock;

ULONG cActual = 0;

while (cActual < cElems

&& m_cursor != m_pThis->m_statements.end)

{

m_cursor++;

cActual++;

}

Unlock;

return cElems == cActual ? S_OK : S_FALSE;

}

STDMETHODIMP

StatementEnumerator::Reset(void)

{

Lock;

m_cursor = m_pThis->m_statements.begin;

Unlock;

return S_OK;

}

STDMETHODIMP

StatementEnumerator::Clone(IEnumString **ppes)

{

if (ppes == 0)

return E_INVALIDARG;

if (*ppes = new StatementEnumerator(m_pThis))

return S_OK;

return E_OUTOFMEMORY;

}

// class ChatSessionClass /////////////////////

ChatSessionClass::ChatSessionClass(void)

: m_cStrongLocks(0)

{

InitializeCriticalSection(&m_csSessionLock);

}

ChatSessionClass::~ChatSessionClass(void)

{

DeleteCriticalSection(&m_csSessionLock);

}

void

ChatSessionClass::Lock(void)

{

EnterCriticalSection(&m_csSessionLock);

}

void

ChatSessionClass::Unlock(void)

{

LeaveCriticalSection(&m_csSessionLock);

}

// helper method to protect access to DeleteSession

// to only allow COMChat Admins to delete groups

bool

ChatSessionClass::CheckAccess(const OLECHAR *pwszUser)

{

if (wcscmp(pwszUser, L"anonymous") == 0)

return false;

TRUSTEEW trustee = {

0, NO_MULTIPLE_TRUSTEE, TRUSTEE_IS_NAME,

TRUSTEE_IS_USER, const_cast(pwszUser)

};

BOOL bIsAllowed;

HRESULT hr = g_pacAdmins->IsAccessAllowed(&trustee,0,

COM_RIGHTS_EXECUTE,

&bIsAllowed);

if (FAILED(hr))

bIsAllowed = false;

return SUCCEEDED(hr) && bIsAllowed != FALSE;

}

// IUnknown methods

STDMETHODIMP

ChatSessionClass::QueryInterface(REFIID riid, void **ppv)

{

if (riid == IID_IUnknown)

*ppv = static_cast(this);

else if (riid == IID_IChatSessionManager)

*ppv = static_cast(this);

else if (riid == IID_IExternalConnection)

*ppv = static_cast(this);

else

return (*ppv = 0), E_NOINTERFACE;

reinterpret_cast(*ppv)->AddRef;

return S_OK;

}

STDMETHODIMP_(ULONG)

ChatSessionClass::AddRef(void)

{

return 2;

}

STDMETHODIMP_(ULONG)

ChatSessionClass::Release(void)

{

return 1;

}

// IExternalConnection methods

STDMETHODIMP_(DWORD)

ChatSessionClass::AddConnection(DWORD extconn, DWORD)

{

if (extconn & EXTCONN_STRONG)

{

ModuleLock;

return InterlockedIncrement(&m_cStrongLocks);

}

return 0;

}

STDMETHODIMP_(DWORD)

ChatSessionClass::ReleaseConnection(DWORD extconn, DWORD,

BOOL bLastReleaseKillsStub)

{

if (extconn & EXTCONN_STRONG)

{

LONG res = InterlockedDecrement(&m_cStrongLocks);

if (res == 0 && bLastReleaseKillsStub)

CoDisconnectObject(

static_cast(this), 0);

ModuleUnlock;

return res;

}

return 0;

}

// IChatSessionManager methods

STDMETHODIMP

ChatSessionClass::GetSessionNames(IEnumString **ppes)

{

if (ppes == 0)

return E_INVALIDARG;

if (*ppes = new SessionNamesEnumerator(this))

{

(*ppes)->AddRef;

return S_OK;

}

else

return E_OUTOFMEMORY;

}

STDMETHODIMP

ChatSessionClass::FindSession(const OLECHAR *pwszSessionName,

BOOL bDontCreate,

BOOL bAllowAnonymousAccess,

IChatSession **ppcs)

{

if (ppcs == 0)

return E_INVALIDARG;

HRESULT hr = E_FAIL;

*ppcs = 0;

OLECHAR *pwszUser = GetCaller;

Lock;

SESSIONMAP::iterator it = m_sessions.find(pwszSessionName);

if (it == m_sessions.end)

{

if (bDontCreate)

hr = E_FAIL;

else if (!bAllowAnonymousAccess

&& wcscmp(pwszUser, L"anonymous") == 0)

hr = E_ACCESSDENIED;

else

{

ChatSession *pNew =

new ChatSession(pwszSessionName,

bAllowAnonymousAccess != FALSE);

if (pNew)

{

pNew->AddRef;

m_sessions.insert(