Сущность технологии СОМ. Библиотека программиста

bool CheckAccess(const OLECHAR *pwszUser);

protected:

virtual ~ChatSession(void);

void Fire_OnNewStatement(const OLECHAR *pwszUser,

const OLECHAR *pwszStatement);

void Fire_OnNewUser(const OLECHAR *pwszUser);

void Fire_OnUserLeft(const OLECHAR *pwszUser);

public:

ChatSession(const OLECHAR *pwszSessionName,

bool bAllowAnonymousAccess);

void Disconnect(void);

// IUnknown methods

STDMETHODIMP QueryInterface(REFIID riid, void **ppv);

STDMETHODIMP_(ULONG) AddRef(void);

STDMETHODIMP_(ULONG) Release(void);

// IChatSession methods

STDMETHODIMP get_SessionName(OLECHAR **ppwsz);

STDMETHODIMP Say(const OLECHAR *pwszStatement);

STDMETHODIMP GetStatements(IEnumString **ppes);

STDMETHODIMP Advise(IChatSessionEvents *pEventSink,

DWORD *pdwReg);

STDMETHODIMP Unadvise(DWORD dwReg);

};

// this class enumerates the statements of a session

class StatementEnumerator : public IEnumString

{

LONG m_cRef;

ChatSession *m_pThis;

vector::iterator m_cursor;

CRITICAL_SECTION m_csLock;

protected:

void Lock(void);

void Unlock(void);

virtual ~StatementEnumerator(void);

public:

StatementEnumerator(ChatSession *pThis);

// IUnknown methods

STDMETHODIMP QueryInterface(REFIID riid, void **ppv);

STDMETHODIMP_(ULONG) AddRef(void);

STDMETHODIMP_(ULONG) Release(void);

// IEnumString methods

STDMETHODIMP Next(ULONG cElems, OLECHAR **rgElems,

ULONG *pcFetched);

STDMETHODIMP Skip(ULONG cElems);

STDMETHODIMP Reset(void);

STDMETHODIMP Clone(IEnumString **ppes);

};

// this class models the management of chat sessions

// and acts as the class object for CLSID_ChatSession

class ChatSessionClass : public IChatSessionManager,

public IExternalConnection

{

friend class SessionNamesEnumerator;

typedef map SESSIONMAP;

LONG m_cStrongLocks;

SESSIONMAP m_sessions;

CRITICAL_SECTION m_csSessionLock;

void Lock(void);

void Unlock(void);

bool CheckAccess(const OLECHAR *pwszUser);

public:

virtual ~ChatSessionClass(void);

ChatSessionClass(void);

// IUnknown methods

STDMETHODIMP QueryInterface(REFIID riid, void **ppv);

STDMETHODIMP_(ULONG) AddRef(void);

STDMETHODIMP_(ULONG) Release(void);

// IExternalConnection methods

STDMETHODIMP_(DWORD) AddConnection(DWORD extconn, DWORD);

STDMETHODIMP_(DWORD) ReleaseConnection(DWORD extconn, DWORD,

BOOL bLastReleaseKillsStub);

// IChatSessionManager methods

STDMETHODIMP GetSessionNames(IEnumString **ppes);

STDMETHODIMP FindSession(const OLECHAR *pwszSessionName,

BOOL bDontCreate,

BOOL bAllowAnonymousAccess,

IChatSession **ppcs);

STDMETHODIMP DeleteSession(const OLECHAR *pwszSessionName);

};

// this class enumerates the session names of a server

class SessionNamesEnumerator : public IEnumString

{

LONG m_cRef;

vector *m_pStrings;

SessionNamesEnumerator *m_pCloneSource;

vector::iterator m_cursor;

CRITICAL_SECTION m_csLock;

protected:

vector& Strings(void);

void Lock(void);

void Unlock(void);

virtual ~SessionNamesEnumerator(void);

public:

SessionNamesEnumerator(ChatSessionClass *pSessionClass);

SessionNamesEnumerator(SessionNamesEnumerator *pCloneSource);

// IUnknown methods

STDMETHODIMP QueryInterface(REFIID riid, void **ppv);

STDMETHODIMP_(ULONG) AddRef(void);

STDMETHODIMP_(ULONG) Release(void);

// IEnumString methods

STDMETHODIMP Next(ULONG cElems, OLECHAR **rgElems,

ULONG *pcFetched);

STDMETHODIMP Skip(ULONG cElems);

STDMETHODIMP Reset(void);

STDMETHODIMP Clone(IEnumString **ppes);

};

#endif

ChatSession.cpp

/////////////////////////////////////////////////////

//

// ChatSession.cpp

//

// Copyright 1997, Don Box/Addison Wesley

//

// This code accompanies the book "The Component

// Object Model" from Addison Wesley. Blah blah blah

//

//

#include «ChatSession.h»

#include

// these routines are defined in svc.cpp to

// control server lifetime

extern void ModuleLock(void);

extern void ModuleUnlock(void);

// these access control objects are created

// in svc.cpp to control various privileged

// operations. Most operations in this class

// are non-privileged, so anyone can get in.

extern IAccessControl *g_pacUsers;

extern IAccessControl *g_pacAdmins;

// utility functions /////////////////////////

// duplicate an OLECHAR * using CoTaskMemAlloc

OLECHAR *OLESTRDUP(const OLECHAR *pwsz)

{

DWORD cb = sizeof(OLECHAR)*(wcslen(pwsz) + 1);

OLECHAR *pwszResult = (OLECHAR*)CoTaskMemAlloc(cb);

if (pwszResult)

wcscpy(pwszResult, pwsz);

return pwszResult;

}

// get the caller's username (or «anonymous» if

// no authentication was specified by the caller).

OLECHAR *GetCaller(void)

{

OLECHAR *pwsz = 0;

HRESULT hr = CoQueryClientBlanket(0,0,0,0,0,(void**)&pwsz,0);

if (SUCCEEDED(hr))

return OLESTRDUP(pwsz);

else

return OLESTRDUP(OLESTR(«anonymous»));

}

// class ChatSession ///////////////////////////////

ChatSession::ChatSession(const OLECHAR *pwszSessionName,

bool bAllowAnonymousAccess)

: m_cRef(0),

m_bAllowAnonymousAccess(bAllowAnonymousAccess),

m_pHeadListeners(0)

{

wcscpy(m_wszSessionName, pwszSessionName);

InitializeCriticalSection(&m_csStatementLock);

InitializeCriticalSection(&m_csAdviseLock);

}

ChatSession::~ChatSession(void)

{

DeleteCriticalSection(&m_csStatementLock);

DeleteCriticalSection(&m_csAdviseLock);

// tear down connected listeners