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object
]
interface IChatSessionEvents : IUnknown
{
import «objidl.idl»;
HRESULT OnNewUser([in, string] const OLECHAR *pwszUser);
HRESULT OnUserLeft([in, string] const OLECHAR *pwszUser);
HRESULT OnNewStatement([in, string] const OLECHAR *pwszUser,
[in, string] const OLECHAR *pwszStmnt);
}
[
uuid(5223A052-2441-11d1-AF4F-0060976AA886),
object
]
interface IChatSessionManager : IUnknown
{
import «objidl.idl»;
HRESULT GetSessionNames([out] IEnumString **ppes);
HRESULT FindSession([in, string] const OLECHAR *pwszName,
[in] BOOL bDontCreate,
[in] BOOL bAllowAnonymousAccess,
[out] IChatSession **ppcs);
HRESULT DeleteSession([in, string] const OLECHAR *pwszName);
}
cpp_quote(«DEFINE_GUID(CLSID_ChatSession,0x5223a053,0x2441,»)
cpp_quote(«0x11d1,0xaf,0x4f,0x0,0x60,0x97,0x6a,0xa8,0x86);»)
//
// client.cpp
//
// Copyright 1997, Don Box/Addison Wesley
//
// This code accompanies the book "The Component
// Object Model" from Addison Wesley. Blah blah blah
//
//
#define _WIN32_WINNT 0x403
#include <windows.h>
#include <stdio.h>
#include <initguid.h>
#include <wchar.h>
#include «../include/COMChat.h»
#include «../include/COMChat_i.c»
void Error(HRESULT hr, const char *psz)
{
printf(«%s failed and returned 0x%x\n», psz, hr);
}
// utility function to print command line syntax
int Usage(void)
{
const char *psz =
«usage: client.exe <action> <user> <host>\n»
« where:\n»
« action = /sessions|/chat:session|/delete:session\n»
« user = /user:domain\\user /password:pw |»
«/anonymous | <nothing>\n»
« host = /host:hostname | <nothing>\n»;
printf(psz);
return -1;
}
// utility function for printing a list of strings
void PrintAllStrings(IEnumString *pes)
{
enum { CHUNKSIZE = 64 };
OLECHAR *rgpwsz[CHUNKSIZE];
ULONG cFetched;
HRESULT hr;
do
{
hr = pes->Next(CHUNKSIZE, rgpwsz, &cFetched);
if (SUCCEEDED(hr))
{
for (ULONG i = 0; i < cFetched; i++)
if (rgpwsz[i])
{
wprintf(L"%s\n", rgpwsz[i]);
CoTaskMemFree(rgpwsz[i]);
}
}
} while (hr == S_OK);
}
// utility function to print initial state of
// a chat session
void PrintToDate(IChatSession *pcs)
{
IEnumString *pes = 0;
HRESULT hr = pcs->GetStatements(&pes);
if (SUCCEEDED(hr))
{
PrintAllStrings(pes);
pes->Release();
}
}
// this class implements the callback interface
// that receives chat notifications. It simply
// prints the event to the console
class EventSink : public IChatSessionEvents
{
public:
STDMETHODIMP QueryInterface(REFIID riid, void**ppv)
{
if (riid == IID_IUnknown)
*ppv = static_cast<IChatSessionEvents*>(this);
else if (riid == IID_IChatSessionEvents)
*ppv = static_cast<IChatSessionEvents*>(this);
else
return (*ppv = 0), E_NOINTERFACE;
reinterpret_cast<IUnknown*>(*ppv)->AddRef();
return S_OK;
}
STDMETHODIMP_(ULONG) AddRef(void)
{
return 2;
}
STDMETHODIMP_(ULONG) Release(void)
{
return 1;
}
STDMETHODIMP OnNewStatement(const OLECHAR *pwszUser,
const OLECHAR *pwszStmt)
{
wprintf(L"%-14s: %s\n", pwszUser, pwszStmt);
return S_OK;
}
STDMETHODIMP OnNewUser(const OLECHAR *pwszUser)
{
wprintf(L"\n\n>>> Say Hello to %s\n\n", pwszUser);
return S_OK;
}
STDMETHODIMP OnUserLeft(const OLECHAR *pwszUser)
{
wprintf(L"\n\n>>> Say Bye to %s\n\n", pwszUser);
return S_OK;
}
};
// type of operations this client can perform
enum ACTION
{
ACTION_NONE,
ACTION_CHAT,
ACTION_DELETE_SESSION,
ACTION_LIST_SESSION_NAMES,
};
// run chat command
void Chat(const OLECHAR *pwszSession,
IChatSessionManager *pcsm, // manager
COAUTHIDENTITY *pcai, // user
bool bAnonymous) // anonymous
{
// create or get the named session
IChatSession *pcs = 0;
HRESULT hr = pcsm->FindSession(pwszSession, FALSE,
TRUE, &pcs);
if (SUCCEEDED(hr))
{
// adjust security blanket for session interface
if (!bAnonymous)
hr = CoSetProxyBlanket(pcs, RPC_C_AUTHN_WINNT,
RPC_C_AUTHZ_NONE, 0,
RPC_C_AUTHN_LEVEL_PKT,
RPC_C_IMP_LEVEL_IDENTIFY,
pcai, EOAC_NONE);
// catch up on past messages
PrintToDate(pcs);
// hook up event sink to receive new messages
EventSink es;
DWORD dwReg;
hr = pcs->Advise(&es, &dwReg);
if (SUCCEEDED(hr))
{
// run UI loop to get statements from console and send them
OLECHAR wszStmt[4096];
while (_getws(wszStmt))
{
hr = pcs->Say(wszStmt);
if (FAILED(hr))
Error(hr, «Say»);
}
// tear down connection for event sink
pcs->Unadvise(dwReg);
}
else
Error(hr, «Advise»);
// release chat session
pcs->Release();
}
else
Error(hr, «FindSession»);
}
// run delete command
void Delete(const OLECHAR *pwszSession,
IChatSessionManager *pcsm)
{
HRESULT hr = pcsm->DeleteSession(pwszSession);
if (FAILED(hr))
Error(hr, «DeleteSession»);
}
// run list command
void List(IChatSessionManager *pcsm)
{
IEnumString *pes = 0;
HRESULT hr = pcsm->GetSessionNames(&pes);
if (SUCCEEDED(hr))
{
printf(«Active Sessions:\n»);
PrintAllStrings(pes);
pes->Release();
}
}
int main(int argc, char **argv)
{
// declare client control state
bool bAnonymous = false;
static OLECHAR wszSessionName[1024];
static OLECHAR wszDomainName[1024];
static OLECHAR wszUserName[1024];
static OLECHAR wszPassword[1024];
static OLECHAR wszHostName[1024];
COSERVERINFO csi = { 0, wszHostName, 0, 0 };
COSERVERINFO *pcsi = 0;
COAUTHIDENTITY cai = {
wszUserName,
0,
wszDomainName,
0,
wszPassword,
0,
SEC_WINNT_AUTH_IDENTITY_UNICODE
};
static COAUTHIDENTITY *pcai = 0;
static ACTION action = ACTION_NONE;
// parse command line
for (int i = 1; i < argc; i++)
{
if (strcmp(argv[i], «/anonymous») == 0)
bAnonymous = true;
else if (strstr(argv[i], «/delete:») == argv[i])
{
if (action != ACTION_NONE)
return Usage();
action = ACTION_DELETE_SESSION;
mbstowcs(wszSessionName, argv[i] + 8, 1024);
}
else if (strstr(argv[i], «/chat:») == argv[i])
{
if (action != ACTION_NONE)
return Usage();
action = ACTION_CHAT;
mbstowcs(wszSessionName, argv[i] + 6, 1024);
}
else if (strcmp(argv[i], «/sessions») == 0)
{
if (action != ACTION_NONE)
return Usage();
action = ACTION_LIST_SESSION_NAMES;
}
else if (strstr(argv[i], «/host:») == argv[i])
{
if (pcsi != 0)
return Usage();
mbstowcs(wszHostName, argv[i] + 6, 1024);
pcsi = &csi;
}
else if (strstr(argv[i], «/password:») == argv[i])
{
mbstowcs(wszPassword, argv[i] + 10, 1024);
cai.PasswordLength = wcslen(wszPassword);
}
else if (strstr(argv[i], «/user:») == argv[i])
{
if (pcai != 0 || bAnonymous)
return Usage();
char *pszDelim = strchr(argv[i] + 7, '\\');
if (pszDelim == 0)
return Usage();
*pszDelim = 0;
pszDelim++;
mbstowcs(wszDomainName, argv[i] + 6, 1024);
cai.DomainLength = wcslen(wszDomainName);
mbstowcs(wszUserName, pszDelim, 1024);
cai.UserLength = wcslen(wszUserName);
pcai = &cai;
}
}
if (action == ACTION_NONE)
return Usage();
HRESULT hr = CoInitializeEx(0, COINIT_MULTITHREADED);
if (FAILED(hr))
return hr;
// allow anonymous callbacks from chat server
hr = CoInitializeSecurity(0, -1, 0, 0,
RPC_C_AUTHN_LEVEL_NONE,
RPC_C_IMP_LEVEL_ANONYMOUS,
0, EOAC_NONE, 0);
if (SUCCEEDED(hr))
{
// grab the requested session manager
IChatSessionManager *pcsm = 0;
hr = CoGetClassObject(CLSID_ChatSession, CLSCTX_ALL,
pcsi, IID_IChatSessionManager,
(void**)&pcsm);
if (SUCCEEDED(hr))
{
// apply security blanket if desired
if (!bAnonymous)
hr = CoSetProxyBlanket(pcsm, RPC_C_AUTHN_WINNT,
RPC_C_AUTHZ_NONE, 0,
RPC_C_AUTHN_LEVEL_PKT,
RPC_C_IMP_LEVEL_IDENTIFY,
pcai, EOAC_NONE);
// dispatch request
switch (action)
{
case ACTION_CHAT:
Chat(wszSessionName, pcsm, pcai, bAnonymous);
break;
case ACTION_DELETE_SESSION:
Delete(wszSessionName, pcsm);
break;
case ACTION_LIST_SESSION_NAMES:
List(pcsm);
break;
default:
Usage();
}
// release session manager
pcsm->Release();
}
}
CoUninitialize();
return hr;
}
//
// ChatSession.h
//
// Copyright 1997, Don Box/Addison Wesley
//
// This code accompanies the book "The Component
// Object Model" from Addison Wesley. Blah blah blah
//
//
#ifndef _CHATSESSION_H
#define _CHATSESSION_H
// this pragma shuts up the compiler warnings due to
// the pre MSC11SP1 debugger choking on long template names.
#pragma warning(disable:4786)
#define _WIN32_WINNT 0x403
#include <windows.h>
#include <map>
#include <vector>
#include <string>
using namespace std;
// bring in IDL-generated interface definitions
#include «..\include\COMChat.h»
// this class models a particular chat session
class ChatSession : public IChatSession
{
friend class StatementEnumerator;
LONG m_cRef;
CRITICAL_SECTION m_csStatementLock;
CRITICAL_SECTION m_csAdviseLock;
OLECHAR m_wszSessionName[1024];
bool m_bIsDeleted;
bool m_bAllowAnonymousAccess;
vector<wstring> m_statements;
struct LISTENER
{
LISTENER *pPrev;
LISTENER *pNext;
OLECHAR *pwszUser;
IChatSessionEvents *pItf;
};
LISTENER *m_pHeadListeners;
void SLock(void);
void SUnlock(void);
void ALock(void);
void AUnlock(void);
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<wstring>::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<wstring, ChatSession *> 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<wstring> *m_pStrings;
SessionNamesEnumerator *m_pCloneSource;
vector<wstring>::iterator m_cursor;
CRITICAL_SECTION m_csLock;
protected:
vector<wstring>& 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
//
// 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 <iaccess.h>
// 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
while (m_pHeadListeners)
{
LISTENER *pThisNode = m_pHeadListeners;
if (pThisNode->pItf)
pThisNode->pItf->Release();
if (pThisNode->pwszUser)
CoTaskMemFree(pThisNode->pwszUser);
m_pHeadListeners = pThisNode->pNext;
delete pThisNode;
}
}
// helper methods ///////////
void ChatSession::Disconnect(void)
{
CoDisconnectObject(this, 0);
// tear down connected listeners
ALock();
while (m_pHeadListeners)
{
LISTENER *pThisNode = m_pHeadListeners;
if (pThisNode->pItf)
pThisNode->pItf->Release();
if (pThisNode->pwszUser)
CoTaskMemFree(pThisNode->pwszUser);
m_pHeadListeners = pThisNode->pNext;
delete pThisNode;
}
AUnlock();
}
// send the OnNewStatement event to all listeners
void
ChatSession::Fire_OnNewStatement(const OLECHAR *pwszUser,
const OLECHAR *pwszStatement)
{
ALock();
for (LISTENER *pNode = m_pHeadListeners;
pNode != 0; pNode = pNode->pNext)
{
if (pNode->pItf)
pNode->pItf->OnNewStatement(pwszUser, pwszStatement);
}
AUnlock();
}
// send the OnNewUser event to all listeners
void
ChatSession::Fire_OnNewUser(const OLECHAR *pwszUser)
{
ALock();
for (LISTENER *pNode = m_pHeadListeners;
pNode != 0; pNode = pNode->pNext)
{
if (pNode->pItf)
pNode->pItf->OnNewUser(pwszUser);
}
AUnlock();
}
// send the OnUserLeft event to all listeners
void
ChatSession::Fire_OnUserLeft(const OLECHAR *pwszUser)
{
ALock();
for (LISTENER *pNode = m_pHeadListeners;
pNode != 0; pNode = pNode->pNext)
{
if (pNode->pItf)
pNode->pItf->OnUserLeft(pwszUser);
}
AUnlock();
}
// lock wrappers
void ChatSession::SLock(void)
{
EnterCriticalSection(&m_csStatementLock);
}
void ChatSession::SUnlock(void)
{
LeaveCriticalSection(&m_csStatementLock);
}
void ChatSession::ALock(void)
{
EnterCriticalSection(&m_csAdviseLock);
}
void ChatSession::AUnlock(void)
{
LeaveCriticalSection(&m_csAdviseLock);
}
// helper method to check access to Say method
bool
ChatSession::CheckAccess(const OLECHAR *pwszUser)
{
if (wcscmp(pwszUser, L"anonymous") == 0)
return m_bAllowAnonymousAccess;
// form trustee from caller and use Access Control
// object hardwired to COMChat Users group
TRUSTEEW trustee = {
0, NO_MULTIPLE_TRUSTEE, TRUSTEE_IS_NAME,
TRUSTEE_IS_USER,
const_cast<OLECHAR*>(pwszUser)
};
BOOL bIsAllowed;
HRESULT hr = g_pacUsers->IsAccessAllowed(&trustee,0,
COM_RIGHTS_EXECUTE,
&bIsAllowed);
return SUCCEEDED(hr) && bIsAllowed != FALSE;
}
// IUnknown methods
STDMETHODIMP
ChatSession::QueryInterface(REFIID riid, void **ppv)
{
if (riid == IID_IUnknown)
*ppv = static_cast<IChatSession*>(this);
else if (riid == IID_IChatSession)
*ppv = static_cast<IChatSession*>(this);
else
return (*ppv = 0), E_NOINTERFACE;
reinterpret_cast<IUnknown*>(*ppv)->AddRef();
return S_OK;
}
STDMETHODIMP_(ULONG)
ChatSession::AddRef(void)
{
ModuleLock();
return InterlockedIncrement(&m_cRef);
}
STDMETHODIMP_(ULONG)
ChatSession::Release(void)
{
LONG res = InterlockedDecrement(&m_cRef);
if (res == 0)
delete this;
ModuleUnlock();
return res;
}
// IChatSession methods
STDMETHODIMP
ChatSession::get_SessionName(OLECHAR **ppwsz)
{
if (!ppwsz)
return E_INVALIDARG;
else if ((*ppwsz = OLESTRDUP(m_wszSessionName)) == 0)
return E_OUTOFMEMORY;
return S_OK;
}
STDMETHODIMP
ChatSession::Say(const OLECHAR *pwszStatement)
{
HRESULT hr = S_OK;
// protect access to method
OLECHAR *pwszUser = GetCaller();
if (pwszUser && CheckAccess(pwszUser))
{
SLock();
try
{
wstring s = pwszUser;
s += L":";
s += pwszStatement;
m_statements.push_back(s);
}
catch(...)
{
hr = E_OUTOFMEMORY;
}
SUnlock();
if (SUCCEEDED(hr))
Fire_OnNewStatement(pwszUser, pwszStatement);
}
else
hr = E_ACCESSDENIED;
CoTaskMemFree(pwszUser);
return hr;
}
STDMETHODIMP
ChatSession::GetStatements(IEnumString **ppes)
{
if (ppes == 0)
return E_INVALIDARG;
*ppes = new StatementEnumerator(this);
if (*ppes == 0)
return E_OUTOFMEMORY;
(*ppes)->AddRef();
return S_OK;
}
STDMETHODIMP
ChatSession::Advise(IChatSessionEvents *pEventSink,
DWORD *pdwReg)
{
HRESULT hr = S_OK;
if (pEventSink == 0 || pdwReg == 0)
return E_INVALIDARG;
LISTENER *pNew = new LISTENER;
if (pNew == 0)
return E_OUTOFMEMORY;
OLECHAR *pwszUser = GetCaller();
if (pwszUser)
{
Fire_OnNewUser(pwszUser);
ALock();
pNew->pwszUser = pwszUser;
if (pNew->pItf = pEventSink)
pEventSink->AddRef();
pNew->pNext = m_pHeadListeners;
if (m_pHeadListeners)
m_pHeadListeners->pPrev = pNew;
pNew->pPrev = 0;
m_pHeadListeners = pNew;
AUnlock();
}
else
{
delete pNew;
return E_OUTOFMEMORY;
}
*pdwReg = reinterpret_cast<DWORD>(pNew);
return hr;
}
STDMETHODIMP
ChatSession::Unadvise(DWORD dwReg)
{
if (dwReg == 0)
return E_INVALIDARG;
HRESULT hr = S_OK;
LISTENER *pThisNode = reinterpret_cast<LISTENER *>(dwReg);
ALock();
if (pThisNode->pPrev)
pThisNode->pPrev->pNext = pThisNode->pNext;
else
m_pHeadListeners = pThisNode->pNext;
if (pThisNode->pNext)
pThisNode->pNext->pPrev = pThisNode->pPrev;
if (pThisNode->pItf)
pThisNode->pItf->Release();
OLECHAR *pwszUser = pThisNode->pwszUser;
delete pThisNode;
AUnlock();
Fire_OnUserLeft(pwszUser);
CoTaskMemFree(pwszUser);
return hr;
}
// class StatementEnumerator ///////////////////
StatementEnumerator::StatementEnumerator(ChatSession *pThis)
: m_cRef(0),
m_pThis(pThis),
m_cursor(pThis->m_statements.begin())
{
m_pThis->AddRef();
InitializeCriticalSection(&m_csLock);
}
StatementEnumerator::~StatementEnumerator(void)
{
m_pThis->Release();
DeleteCriticalSection(&m_csLock);
}
// lock helpers (note that ChatSession is locked
// 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<IEnumString*>(this);
else if (riid == IID_IEnumString)
*ppv = static_cast<IEnumString*>(this);
else
return (*ppv = 0), E_NOINTERFACE;
reinterpret_cast<IUnknown*>(*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<OLECHAR*>(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<IChatSessionManager*>(this);
else if (riid == IID_IChatSessionManager)
*ppv = static_cast<IChatSessionManager*>(this);
else if (riid == IID_IExternalConnection)
*ppv = static_cast<IExternalConnection*>(this);
else
return (*ppv = 0), E_NOINTERFACE;
reinterpret_cast<IUnknown*>(*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<IExternalConnection*>(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(
pair<wstring,
ChatSession*>(pwszSessionName,
pNew));
(*ppcs = pNew)->AddRef();
hr = S_OK;
}
else
hr = E_OUTOFMEMORY;
}
}
else
{
(*ppcs = (*it).second)->AddRef();
hr = S_OK;
}
Unlock();
CoTaskMemFree(pwszUser);
return hr;
}
STDMETHODIMP
ChatSessionClass::DeleteSession(const OLECHAR *pwszSessionName)
{
if (pwszSessionName == 0)
return E_INVALIDARG;
HRESULT hr = E_FAIL;
OLECHAR *pwszUser = GetCaller();
if (CheckAccess(pwszUser))
{
Lock();
SESSIONMAP::iterator it
= m_sessions.find(pwszSessionName);
if (it == m_sessions.end())
{
hr = E_FAIL;
}
else
{
(*it).second->Disconnect();
(*it).second->Release();
m_sessions.erase(it);
hr = S_OK;
}
Unlock();
}
else
hr = E_ACCESSDENIED;
CoTaskMemFree(pwszUser);
return hr;
}
// class SessionNamesEnumerator
vector<wstring>&
SessionNamesEnumerator::Strings(void)
{
if (m_pStrings)
return *m_pStrings;
else
return *(m_pCloneSource->m_pStrings);
}
void
SessionNamesEnumerator::Lock(void)
{
EnterCriticalSection(&m_csLock);
}
void
SessionNamesEnumerator::Unlock(void)
{
LeaveCriticalSection(&m_csLock);
}
SessionNamesEnumerator::SessionNamesEnumerator(
ChatSessionClass *pSessionClass)
: m_cRef(0),
m_pStrings(0),
m_pCloneSource(0)
{
typedef ChatSessionClass::SESSIONMAP::iterator iterator;
ChatSessionClass::SESSIONMAP &sessions
= pSessionClass->m_sessions;
m_pStrings = new vector<wstring>;
pSessionClass->Lock();
for (iterator it = sessions.begin();
it != sessions.end();
it++)
{
m_pStrings->push_back((*it).first);
}
pSessionClass->Unlock();
m_cursor = Strings().begin();
InitializeCriticalSection(&m_csLock);
}
SessionNamesEnumerator::SessionNamesEnumerator(
SessionNamesEnumerator *pCloneSource)
: m_cRef(0),
m_pStrings(0),
m_pCloneSource(pCloneSource)
{
m_pCloneSource->AddRef();
m_cursor = Strings().begin();
InitializeCriticalSection(&m_csLock);
}
SessionNamesEnumerator::~SessionNamesEnumerator(void)
{
if (m_pCloneSource)
m_pCloneSource->Release();
else if (m_pStrings)
delete m_pStrings;
DeleteCriticalSection(&m_csLock);
}
// IUnknown methods
STDMETHODIMP
SessionNamesEnumerator::QueryInterface(REFIID riid, void **ppv)
{
if (riid == IID_IUnknown)
*ppv = static_cast<IEnumString*>(this);
else if (riid == IID_IEnumString)
*ppv = static_cast<IEnumString*>(this);
else
return (*ppv = 0), E_NOINTERFACE;
reinterpret_cast<IUnknown*>(*ppv)->AddRef();
return S_OK;
}
STDMETHODIMP_(ULONG)
SessionNamesEnumerator::AddRef(void)
{
ModuleLock();
return InterlockedIncrement(&m_cRef);
}
STDMETHODIMP_(ULONG)
SessionNamesEnumerator::Release(void)
{
LONG res = InterlockedDecrement(&m_cRef);
if (res == 0)
delete this;
ModuleUnlock();
return res;
}
// IEnumString methods
STDMETHODIMP
SessionNamesEnumerator::Next(ULONG cElems, OLECHAR **rgElems,
ULONG *pcFetched)
{
if (cElems > 1 && pcFetched == 0)
return E_INVALIDARG;
ULONG cActual = 0;
vector<wstring> &rstrings = Strings();
Lock();
while (cActual < cElems
&& m_cursor != rstrings.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 (cActual)
*pcFetched = cActual;
return cActual == cElems ? S_OK : S_FALSE;
}
STDMETHODIMP
SessionNamesEnumerator::Skip(ULONG cElems)
{
ULONG cActual = 0;
vector<wstring> &rstrings = Strings();
Lock();
while (cActual < cElems
&& m_cursor != rstrings.end())
{
m_cursor++;
cActual++;
}
Unlock();
return cActual == cElems ? S_OK : S_FALSE;
}
STDMETHODIMP
SessionNamesEnumerator::Reset(void)
{
Lock();
m_cursor = Strings().begin();
Unlock();
return S_OK;
}
STDMETHODIMP
SessionNamesEnumerator::Clone(IEnumString **ppes)
{
if (ppes == 0)
return E_INVALIDARG;
SessionNamesEnumerator *pCloneSource = m_pCloneSource;
if (pCloneSource == 0) // we are the source
m_pCloneSource = this;
*ppes = new SessionNamesEnumerator(pCloneSource);
if (*ppes)
{
(*ppes)->AddRef();
return S_OK;
}
return E_OUTOFMEMORY;
}
//
// svc.cpp
//
// Copyright 1997, Don Box/Addison Wesley
//
// This code accompanies the book "The Component
// Object Model" from Addison Wesley. Blah blah blah
//
//
#define _WIN32_WINNT 0x403
#include <windows.h>
#include <olectl.h>
#include <initguid.h>
#include <iaccess.h>
#include «ChatSession.h»
#include «../include/COMChat_i.c»
#if !defined(HAVE_IID_IACCESSCONTROL)
// there is a common bug is the SDK headers and libs
// that causes IID_IAccessControl to be undefined.
// We define it here to give the GUID linkage.
DEFINE_GUID(IID_IAccessControl,0xEEDD23E0, 0x8410, 0x11CE,
0xA1, 0xC3, 0x08, 0x00, 0x2B, 0x2B, 0x8D, 0x8F);
#endif
// standard MTA lifetime management helpers
HANDLE g_heventDone = CreateEvent(0, TRUE, FALSE, 0);
void ModuleLock(void)
{
CoAddRefServerProcess();
}
void ModuleUnlock(void)
{
if (CoReleaseServerProcess() == 0)
SetEvent(g_heventDone);
}
// standard self-registration table
const char *g_RegTable[][3] = {
{ «CLSID\\{5223A053-2441-11d1-AF4F-0060976AA886}»,
0, «ChatSession» },
{ «CLSID\\{5223A053-2441-11d1-AF4F-0060976AA886}»,
«AppId», «{5223A054-2441-11d1-AF4F-0060976AA886}»
},
{ «CLSID\\{5223A053-2441-11d1-AF4F-0060976AA886}\\LocalServer32»,
0, (const char*)-1 // rogue value indicating file name
},
{ «AppID\\{5223A054-2441-11d1-AF4F-0060976AA886}»,
0, «ChatSession Server» },
{ «AppID\\{5223A054-2441-11d1-AF4F-0060976AA886}»,
«RunAs», «Domain\\ReplaceMe»
},
{ «AppID\\{5223A054-2441-11d1-AF4F-0060976AA886}»,
«Chat Admins Group», «Domain\\ReplaceMe»
},
{ «AppID\\{5223A054-2441-11d1-AF4F-0060976AA886}»,
«Chat Users Group», «Domain\\ReplaceMe»
},
{ «AppID\\COMChat.exe»,
«AppId», «{5223A054-2441-11d1-AF4F-0060976AA886}»
},
};
// self-unregistration routine
STDAPI UnregisterServer(void) {
HRESULT hr = S_OK;
int nEntries = sizeof(g_RegTable)/sizeof(*g_RegTable);
for (int i = nEntries – 1; i >= 0; i–){
const char *pszKeyName = g_RegTable[i][0];
long err = RegDeleteKeyA(HKEY_CLASSES_ROOT, pszKeyName);
if (err != ERROR_SUCCESS)
hr = S_FALSE;
}
return hr;
}
// self-registration routine
STDAPI RegisterServer(HINSTANCE hInstance = 0) {
HRESULT hr = S_OK;
// look up server's file name
char szFileName[MAX_PATH];
GetModuleFileNameA(hInstance, szFileName, MAX_PATH);
// register entries from table
int nEntries = sizeof(g_RegTable)/sizeof(*g_RegTable);
for (int i = 0; SUCCEEDED(hr) && i < nEntries; i++) {
const char *pszKeyName = g_RegTable[i][0];
const char *pszValueName = g_RegTable[i][1];
const char *pszValue = g_RegTable[i][2];
// map rogue value to module file name
if (pszValue == (const char*)-1)
pszValue = szFileName;
HKEY hkey;
// create the key
long err = RegCreateKeyA(HKEY_CLASSES_ROOT,
pszKeyName, &hkey);
if (err == ERROR_SUCCESS) {
// set the value
err = RegSetValueExA(hkey, pszValueName, 0,
REG_SZ, (const BYTE*)pszValue,
(strlen(pszValue) + 1));
RegCloseKey(hkey);
}
if (err != ERROR_SUCCESS) {
// if cannot add key or value, back out and fail
UnregisterServer();
hr = SELFREG_E_CLASS;
}
}
return hr;
}
// these point to standard access control objects
// used to protect particular methods
IAccessControl *g_pacUsers = 0;
IAccessControl *g_pacAdmins = 0;
// this routine is called at process init time
// to build access control objects and to allow
// anonymous access to server by default
HRESULT InitializeApplicationSecurity(void)
{
// load groupnames from registry
static OLECHAR wszAdminsGroup[1024];
static OLECHAR wszUsersGroup[1024];
HKEY hkey;
long err = RegOpenKeyEx(HKEY_CLASSES_ROOT,
__TEXT(«AppID\\{5223A054-2441-11d1-AF4F-0060976AA886}»),
0, KEY_QUERY_VALUE,
&hkey);
if (err == ERROR_SUCCESS)
{
DWORD cb = sizeof(wszAdminsGroup);
err = RegQueryValueExW(hkey, L"Chat Admins Group",
0, 0, (BYTE*)wszAdminsGroup,
&cb);
cb = sizeof(wszAdminsGroup);
if (err == ERROR_SUCCESS)
err = RegQueryValueExW(hkey,
L"Chat Users Group",
0, 0, (BYTE*)wszUsersGroup,
&cb);
RegCloseKey(hkey);
}
if (err != ERROR_SUCCESS)
return MAKE_HRESULT(SEVERITY_ERROR, FACILITY_WIN32,
GetLastError());
// declare vectors of user/groups for 2 access
// control objects
ACTRL_ACCESS_ENTRYW rgaaeUsers[] = {
{ {0, NO_MULTIPLE_TRUSTEE, TRUSTEE_IS_NAME,
TRUSTEE_IS_GROUP, wszUsersGroup },
ACTRL_ACCESS_ALLOWED, COM_RIGHTS_EXECUTE, 0,
NO_INHERITANCE, 0 },
};
ACTRL_ACCESS_ENTRY_LISTW aaelUsers = {
sizeof(rgaaeUsers)/sizeof(*rgaaeUsers),
rgaaeUsers
};
ACTRL_PROPERTY_ENTRYW apeUsers = { 0, &aaelUsers, 0 };
ACTRL_ACCESSW aaUsers = { 1, &apeUsers };
ACTRL_ACCESS_ENTRYW rgaaeAdmins[] = {
{ {0, NO_MULTIPLE_TRUSTEE, TRUSTEE_IS_NAME,
TRUSTEE_IS_GROUP, wszAdminsGroup },
ACTRL_ACCESS_ALLOWED, COM_RIGHTS_EXECUTE, 0,
NO_INHERITANCE, 0 },
};
ACTRL_ACCESS_ENTRY_LISTW aaelAdmins = {
sizeof(rgaaeAdmins)/sizeof(*rgaaeAdmins),
rgaaeAdmins
};
ACTRL_PROPERTY_ENTRYW apeAdmins = { 0, &aaelAdmins, 0 };
ACTRL_ACCESSW aaAdmins = { 1, &apeAdmins };
HRESULT hr = CoInitializeSecurity(0, -1, 0, 0,
RPC_C_AUTHN_LEVEL_NONE,
RPC_C_IMP_LEVEL_ANONYMOUS,
0,
EOAC_NONE,
0);
if (SUCCEEDED(hr))
{
hr = CoCreateInstance(CLSID_DCOMAccessControl,
0, CLSCTX_ALL, IID_IAccessControl,
(void**)&g_pacUsers);
if (SUCCEEDED(hr))
hr = g_pacUsers->SetAccessRights(&aaUsers);
if (SUCCEEDED(hr))
{
hr = CoCreateInstance(CLSID_DCOMAccessControl,
0, CLSCTX_ALL,
IID_IAccessControl,
(void**)&g_pacAdmins);
if (SUCCEEDED(hr))
hr = g_pacAdmins->SetAccessRights(&aaAdmins);
}
if (FAILED(hr))
{
if (g_pacAdmins)
{
g_pacAdmins->Release();
g_pacAdmins = 0;
}
if (g_pacUsers)
{
g_pacUsers->Release();
g_pacUsers = 0;
}
}
}
return hr;
}
// the main thread routine that simply registers the class
// object and waits to die
int WINAPI WinMain(HINSTANCE, HINSTANCE,
LPSTR szCmdParam, int)
{
const TCHAR *pszPrompt =
__TEXT("Ensure that you have properly ")
__TEXT("configured the application to ")
__TEXT("run as a particular user and that ")
__TEXT("you have manually changed the ")
__TEXT("Users and Admins Group registry ")
__TEXT(«settings under this server's AppID.»);
HRESULT hr = CoInitializeEx(0, COINIT_MULTITHREADED);
if (FAILED(hr))
return hr;
// look for self-registration flags
if (strstr(szCmdParam, «/UnregServer») != 0
|| strstr(szCmdParam, «-UnregServer») != 0)
{
hr = UnregisterServer();
CoUninitialize();
return hr;
}
else if (strstr(szCmdParam, «/RegServer») != 0
|| strstr(szCmdParam, «-RegServer») != 0)
{
hr = RegisterServer();
MessageBox(0, pszPrompt, __TEXT(«COMChat»),
MB_SETFOREGROUND);
CoUninitialize();
return hr;
}
// set up process security
hr = InitializeApplicationSecurity();
if (SUCCEEDED(hr))
{
// register class object and wait to die
DWORD dwReg;
static ChatSessionClass cmc;
hr = CoRegisterClassObject(CLSID_ChatSession,
static_cast<IExternalConnection*>(&cmc),
CLSCTX_LOCAL_SERVER
REGCLS_SUSPENDED|REGCLS_MULTIPLEUSE,
&dwReg);
if (SUCCEEDED(hr))
{
hr = CoResumeClassObjects();
if (SUCCEEDED(hr))
WaitForSingleObject(g_heventDone, INFINITE);
CoRevokeClassObject(dwReg);
}
g_pacUsers->Release();
g_pacAdmins->Release();
}
if (FAILED(hr))
MessageBox(0, pszPrompt, __TEXT(«Error»),
MB_SETFOREGROUND);
CoUninitialize();
return 0;
}
Source Code
COM Chat Compilable versions of the source code in Appendix B of the book.
YACL Yet another COM library. Contains the various macros and C++ classes described in the book.
IGlobalInterfaceTable Wrapper/Sample A simplification of apartment-independent pointer use.
HostHook A custom channel hook that allows you to find out the caller's and callee's network address.
APTSUR A custom surrogate that spawns distinct STA threads for each activation request.
Custom Moniker Stuff I worked with some friends on a custom moniker framework. Here is some of the 1st bits and pieces.
Yet Another COM Library (YACL) – Preview
This is my first drop. It contains a family of preprocessor macros that automate the boilerplate activities used in COM programming.
Please send comments and bug reports to cbbugs@braintrust.com
The freshest drop is always available at http://www.develop.com/dbox/yacl.zip
Design Goals (in Order)
Easily used without Wizard support
Easily kept in one's head
Modular (use only what you need and nothing else)
Extensible
Small Code
Fast Code
No DLL ever
Compiler-friendly
Platform-neutral where possible (including 16-bit Windows)
Current Feature Set
Anal-rententive Smart Pointer
Efficient and intuitive Unicode handling
Table-driven QueryInterface
Table-driven Registration
Table-driven Class management
Generic Class Factory implementation.
Preprocessor macros for de facto IUnknown implementation techniques.
Preprocessor macros for de facto module management routines.
Preprocessor macros for de facto DllXXX routines.
Preprocessor macros for de facto out-of-proc CRCO/Wait/CRCO sequence.
Planned Work
Performance/size tuning
Compiler/Platform testing
Verify ATL/MFC interoperation
Macro-ization of smart pointer for 16-bit windows
Add optional exception semantics to smart pointer
Map COM hresults/exception to C++ exceptions
Add support for IDispatch and friends
Add support for IConnectionPoint and friends
Add IEnum -> stl thunks
]
interface IChatSessionEvents : IUnknown
{
import «objidl.idl»;
HRESULT OnNewUser([in, string] const OLECHAR *pwszUser);
HRESULT OnUserLeft([in, string] const OLECHAR *pwszUser);
HRESULT OnNewStatement([in, string] const OLECHAR *pwszUser,
[in, string] const OLECHAR *pwszStmnt);
}
[
uuid(5223A052-2441-11d1-AF4F-0060976AA886),
object
]
interface IChatSessionManager : IUnknown
{
import «objidl.idl»;
HRESULT GetSessionNames([out] IEnumString **ppes);
HRESULT FindSession([in, string] const OLECHAR *pwszName,
[in] BOOL bDontCreate,
[in] BOOL bAllowAnonymousAccess,
[out] IChatSession **ppcs);
HRESULT DeleteSession([in, string] const OLECHAR *pwszName);
}
cpp_quote(«DEFINE_GUID(CLSID_ChatSession,0x5223a053,0x2441,»)
cpp_quote(«0x11d1,0xaf,0x4f,0x0,0x60,0x97,0x6a,0xa8,0x86);»)
client.cpp
///////////////////////////////////////////////////////
// client.cpp
//
// Copyright 1997, Don Box/Addison Wesley
//
// This code accompanies the book "The Component
// Object Model" from Addison Wesley. Blah blah blah
//
//
#define _WIN32_WINNT 0x403
#include <windows.h>
#include <stdio.h>
#include <initguid.h>
#include <wchar.h>
#include «../include/COMChat.h»
#include «../include/COMChat_i.c»
void Error(HRESULT hr, const char *psz)
{
printf(«%s failed and returned 0x%x\n», psz, hr);
}
// utility function to print command line syntax
int Usage(void)
{
const char *psz =
«usage: client.exe <action> <user> <host>\n»
« where:\n»
« action = /sessions|/chat:session|/delete:session\n»
« user = /user:domain\\user /password:pw |»
«/anonymous | <nothing>\n»
« host = /host:hostname | <nothing>\n»;
printf(psz);
return -1;
}
// utility function for printing a list of strings
void PrintAllStrings(IEnumString *pes)
{
enum { CHUNKSIZE = 64 };
OLECHAR *rgpwsz[CHUNKSIZE];
ULONG cFetched;
HRESULT hr;
do
{
hr = pes->Next(CHUNKSIZE, rgpwsz, &cFetched);
if (SUCCEEDED(hr))
{
for (ULONG i = 0; i < cFetched; i++)
if (rgpwsz[i])
{
wprintf(L"%s\n", rgpwsz[i]);
CoTaskMemFree(rgpwsz[i]);
}
}
} while (hr == S_OK);
}
// utility function to print initial state of
// a chat session
void PrintToDate(IChatSession *pcs)
{
IEnumString *pes = 0;
HRESULT hr = pcs->GetStatements(&pes);
if (SUCCEEDED(hr))
{
PrintAllStrings(pes);
pes->Release();
}
}
// this class implements the callback interface
// that receives chat notifications. It simply
// prints the event to the console
class EventSink : public IChatSessionEvents
{
public:
STDMETHODIMP QueryInterface(REFIID riid, void**ppv)
{
if (riid == IID_IUnknown)
*ppv = static_cast<IChatSessionEvents*>(this);
else if (riid == IID_IChatSessionEvents)
*ppv = static_cast<IChatSessionEvents*>(this);
else
return (*ppv = 0), E_NOINTERFACE;
reinterpret_cast<IUnknown*>(*ppv)->AddRef();
return S_OK;
}
STDMETHODIMP_(ULONG) AddRef(void)
{
return 2;
}
STDMETHODIMP_(ULONG) Release(void)
{
return 1;
}
STDMETHODIMP OnNewStatement(const OLECHAR *pwszUser,
const OLECHAR *pwszStmt)
{
wprintf(L"%-14s: %s\n", pwszUser, pwszStmt);
return S_OK;
}
STDMETHODIMP OnNewUser(const OLECHAR *pwszUser)
{
wprintf(L"\n\n>>> Say Hello to %s\n\n", pwszUser);
return S_OK;
}
STDMETHODIMP OnUserLeft(const OLECHAR *pwszUser)
{
wprintf(L"\n\n>>> Say Bye to %s\n\n", pwszUser);
return S_OK;
}
};
// type of operations this client can perform
enum ACTION
{
ACTION_NONE,
ACTION_CHAT,
ACTION_DELETE_SESSION,
ACTION_LIST_SESSION_NAMES,
};
// run chat command
void Chat(const OLECHAR *pwszSession,
IChatSessionManager *pcsm, // manager
COAUTHIDENTITY *pcai, // user
bool bAnonymous) // anonymous
{
// create or get the named session
IChatSession *pcs = 0;
HRESULT hr = pcsm->FindSession(pwszSession, FALSE,
TRUE, &pcs);
if (SUCCEEDED(hr))
{
// adjust security blanket for session interface
if (!bAnonymous)
hr = CoSetProxyBlanket(pcs, RPC_C_AUTHN_WINNT,
RPC_C_AUTHZ_NONE, 0,
RPC_C_AUTHN_LEVEL_PKT,
RPC_C_IMP_LEVEL_IDENTIFY,
pcai, EOAC_NONE);
// catch up on past messages
PrintToDate(pcs);
// hook up event sink to receive new messages
EventSink es;
DWORD dwReg;
hr = pcs->Advise(&es, &dwReg);
if (SUCCEEDED(hr))
{
// run UI loop to get statements from console and send them
OLECHAR wszStmt[4096];
while (_getws(wszStmt))
{
hr = pcs->Say(wszStmt);
if (FAILED(hr))
Error(hr, «Say»);
}
// tear down connection for event sink
pcs->Unadvise(dwReg);
}
else
Error(hr, «Advise»);
// release chat session
pcs->Release();
}
else
Error(hr, «FindSession»);
}
// run delete command
void Delete(const OLECHAR *pwszSession,
IChatSessionManager *pcsm)
{
HRESULT hr = pcsm->DeleteSession(pwszSession);
if (FAILED(hr))
Error(hr, «DeleteSession»);
}
// run list command
void List(IChatSessionManager *pcsm)
{
IEnumString *pes = 0;
HRESULT hr = pcsm->GetSessionNames(&pes);
if (SUCCEEDED(hr))
{
printf(«Active Sessions:\n»);
PrintAllStrings(pes);
pes->Release();
}
}
int main(int argc, char **argv)
{
// declare client control state
bool bAnonymous = false;
static OLECHAR wszSessionName[1024];
static OLECHAR wszDomainName[1024];
static OLECHAR wszUserName[1024];
static OLECHAR wszPassword[1024];
static OLECHAR wszHostName[1024];
COSERVERINFO csi = { 0, wszHostName, 0, 0 };
COSERVERINFO *pcsi = 0;
COAUTHIDENTITY cai = {
wszUserName,
0,
wszDomainName,
0,
wszPassword,
0,
SEC_WINNT_AUTH_IDENTITY_UNICODE
};
static COAUTHIDENTITY *pcai = 0;
static ACTION action = ACTION_NONE;
// parse command line
for (int i = 1; i < argc; i++)
{
if (strcmp(argv[i], «/anonymous») == 0)
bAnonymous = true;
else if (strstr(argv[i], «/delete:») == argv[i])
{
if (action != ACTION_NONE)
return Usage();
action = ACTION_DELETE_SESSION;
mbstowcs(wszSessionName, argv[i] + 8, 1024);
}
else if (strstr(argv[i], «/chat:») == argv[i])
{
if (action != ACTION_NONE)
return Usage();
action = ACTION_CHAT;
mbstowcs(wszSessionName, argv[i] + 6, 1024);
}
else if (strcmp(argv[i], «/sessions») == 0)
{
if (action != ACTION_NONE)
return Usage();
action = ACTION_LIST_SESSION_NAMES;
}
else if (strstr(argv[i], «/host:») == argv[i])
{
if (pcsi != 0)
return Usage();
mbstowcs(wszHostName, argv[i] + 6, 1024);
pcsi = &csi;
}
else if (strstr(argv[i], «/password:») == argv[i])
{
mbstowcs(wszPassword, argv[i] + 10, 1024);
cai.PasswordLength = wcslen(wszPassword);
}
else if (strstr(argv[i], «/user:») == argv[i])
{
if (pcai != 0 || bAnonymous)
return Usage();
char *pszDelim = strchr(argv[i] + 7, '\\');
if (pszDelim == 0)
return Usage();
*pszDelim = 0;
pszDelim++;
mbstowcs(wszDomainName, argv[i] + 6, 1024);
cai.DomainLength = wcslen(wszDomainName);
mbstowcs(wszUserName, pszDelim, 1024);
cai.UserLength = wcslen(wszUserName);
pcai = &cai;
}
}
if (action == ACTION_NONE)
return Usage();
HRESULT hr = CoInitializeEx(0, COINIT_MULTITHREADED);
if (FAILED(hr))
return hr;
// allow anonymous callbacks from chat server
hr = CoInitializeSecurity(0, -1, 0, 0,
RPC_C_AUTHN_LEVEL_NONE,
RPC_C_IMP_LEVEL_ANONYMOUS,
0, EOAC_NONE, 0);
if (SUCCEEDED(hr))
{
// grab the requested session manager
IChatSessionManager *pcsm = 0;
hr = CoGetClassObject(CLSID_ChatSession, CLSCTX_ALL,
pcsi, IID_IChatSessionManager,
(void**)&pcsm);
if (SUCCEEDED(hr))
{
// apply security blanket if desired
if (!bAnonymous)
hr = CoSetProxyBlanket(pcsm, RPC_C_AUTHN_WINNT,
RPC_C_AUTHZ_NONE, 0,
RPC_C_AUTHN_LEVEL_PKT,
RPC_C_IMP_LEVEL_IDENTIFY,
pcai, EOAC_NONE);
// dispatch request
switch (action)
{
case ACTION_CHAT:
Chat(wszSessionName, pcsm, pcai, bAnonymous);
break;
case ACTION_DELETE_SESSION:
Delete(wszSessionName, pcsm);
break;
case ACTION_LIST_SESSION_NAMES:
List(pcsm);
break;
default:
Usage();
}
// release session manager
pcsm->Release();
}
}
CoUninitialize();
return hr;
}
ChatSession.h
///////////////////////////////////////////////////////
// ChatSession.h
//
// Copyright 1997, Don Box/Addison Wesley
//
// This code accompanies the book "The Component
// Object Model" from Addison Wesley. Blah blah blah
//
//
#ifndef _CHATSESSION_H
#define _CHATSESSION_H
// this pragma shuts up the compiler warnings due to
// the pre MSC11SP1 debugger choking on long template names.
#pragma warning(disable:4786)
#define _WIN32_WINNT 0x403
#include <windows.h>
#include <map>
#include <vector>
#include <string>
using namespace std;
// bring in IDL-generated interface definitions
#include «..\include\COMChat.h»
// this class models a particular chat session
class ChatSession : public IChatSession
{
friend class StatementEnumerator;
LONG m_cRef;
CRITICAL_SECTION m_csStatementLock;
CRITICAL_SECTION m_csAdviseLock;
OLECHAR m_wszSessionName[1024];
bool m_bIsDeleted;
bool m_bAllowAnonymousAccess;
vector<wstring> m_statements;
struct LISTENER
{
LISTENER *pPrev;
LISTENER *pNext;
OLECHAR *pwszUser;
IChatSessionEvents *pItf;
};
LISTENER *m_pHeadListeners;
void SLock(void);
void SUnlock(void);
void ALock(void);
void AUnlock(void);
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<wstring>::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<wstring, ChatSession *> 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<wstring> *m_pStrings;
SessionNamesEnumerator *m_pCloneSource;
vector<wstring>::iterator m_cursor;
CRITICAL_SECTION m_csLock;
protected:
vector<wstring>& 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 <iaccess.h>
// 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
while (m_pHeadListeners)
{
LISTENER *pThisNode = m_pHeadListeners;
if (pThisNode->pItf)
pThisNode->pItf->Release();
if (pThisNode->pwszUser)
CoTaskMemFree(pThisNode->pwszUser);
m_pHeadListeners = pThisNode->pNext;
delete pThisNode;
}
}
// helper methods ///////////
void ChatSession::Disconnect(void)
{
CoDisconnectObject(this, 0);
// tear down connected listeners
ALock();
while (m_pHeadListeners)
{
LISTENER *pThisNode = m_pHeadListeners;
if (pThisNode->pItf)
pThisNode->pItf->Release();
if (pThisNode->pwszUser)
CoTaskMemFree(pThisNode->pwszUser);
m_pHeadListeners = pThisNode->pNext;
delete pThisNode;
}
AUnlock();
}
// send the OnNewStatement event to all listeners
void
ChatSession::Fire_OnNewStatement(const OLECHAR *pwszUser,
const OLECHAR *pwszStatement)
{
ALock();
for (LISTENER *pNode = m_pHeadListeners;
pNode != 0; pNode = pNode->pNext)
{
if (pNode->pItf)
pNode->pItf->OnNewStatement(pwszUser, pwszStatement);
}
AUnlock();
}
// send the OnNewUser event to all listeners
void
ChatSession::Fire_OnNewUser(const OLECHAR *pwszUser)
{
ALock();
for (LISTENER *pNode = m_pHeadListeners;
pNode != 0; pNode = pNode->pNext)
{
if (pNode->pItf)
pNode->pItf->OnNewUser(pwszUser);
}
AUnlock();
}
// send the OnUserLeft event to all listeners
void
ChatSession::Fire_OnUserLeft(const OLECHAR *pwszUser)
{
ALock();
for (LISTENER *pNode = m_pHeadListeners;
pNode != 0; pNode = pNode->pNext)
{
if (pNode->pItf)
pNode->pItf->OnUserLeft(pwszUser);
}
AUnlock();
}
// lock wrappers
void ChatSession::SLock(void)
{
EnterCriticalSection(&m_csStatementLock);
}
void ChatSession::SUnlock(void)
{
LeaveCriticalSection(&m_csStatementLock);
}
void ChatSession::ALock(void)
{
EnterCriticalSection(&m_csAdviseLock);
}
void ChatSession::AUnlock(void)
{
LeaveCriticalSection(&m_csAdviseLock);
}
// helper method to check access to Say method
bool
ChatSession::CheckAccess(const OLECHAR *pwszUser)
{
if (wcscmp(pwszUser, L"anonymous") == 0)
return m_bAllowAnonymousAccess;
// form trustee from caller and use Access Control
// object hardwired to COMChat Users group
TRUSTEEW trustee = {
0, NO_MULTIPLE_TRUSTEE, TRUSTEE_IS_NAME,
TRUSTEE_IS_USER,
const_cast<OLECHAR*>(pwszUser)
};
BOOL bIsAllowed;
HRESULT hr = g_pacUsers->IsAccessAllowed(&trustee,0,
COM_RIGHTS_EXECUTE,
&bIsAllowed);
return SUCCEEDED(hr) && bIsAllowed != FALSE;
}
// IUnknown methods
STDMETHODIMP
ChatSession::QueryInterface(REFIID riid, void **ppv)
{
if (riid == IID_IUnknown)
*ppv = static_cast<IChatSession*>(this);
else if (riid == IID_IChatSession)
*ppv = static_cast<IChatSession*>(this);
else
return (*ppv = 0), E_NOINTERFACE;
reinterpret_cast<IUnknown*>(*ppv)->AddRef();
return S_OK;
}
STDMETHODIMP_(ULONG)
ChatSession::AddRef(void)
{
ModuleLock();
return InterlockedIncrement(&m_cRef);
}
STDMETHODIMP_(ULONG)
ChatSession::Release(void)
{
LONG res = InterlockedDecrement(&m_cRef);
if (res == 0)
delete this;
ModuleUnlock();
return res;
}
// IChatSession methods
STDMETHODIMP
ChatSession::get_SessionName(OLECHAR **ppwsz)
{
if (!ppwsz)
return E_INVALIDARG;
else if ((*ppwsz = OLESTRDUP(m_wszSessionName)) == 0)
return E_OUTOFMEMORY;
return S_OK;
}
STDMETHODIMP
ChatSession::Say(const OLECHAR *pwszStatement)
{
HRESULT hr = S_OK;
// protect access to method
OLECHAR *pwszUser = GetCaller();
if (pwszUser && CheckAccess(pwszUser))
{
SLock();
try
{
wstring s = pwszUser;
s += L":";
s += pwszStatement;
m_statements.push_back(s);
}
catch(...)
{
hr = E_OUTOFMEMORY;
}
SUnlock();
if (SUCCEEDED(hr))
Fire_OnNewStatement(pwszUser, pwszStatement);
}
else
hr = E_ACCESSDENIED;
CoTaskMemFree(pwszUser);
return hr;
}
STDMETHODIMP
ChatSession::GetStatements(IEnumString **ppes)
{
if (ppes == 0)
return E_INVALIDARG;
*ppes = new StatementEnumerator(this);
if (*ppes == 0)
return E_OUTOFMEMORY;
(*ppes)->AddRef();
return S_OK;
}
STDMETHODIMP
ChatSession::Advise(IChatSessionEvents *pEventSink,
DWORD *pdwReg)
{
HRESULT hr = S_OK;
if (pEventSink == 0 || pdwReg == 0)
return E_INVALIDARG;
LISTENER *pNew = new LISTENER;
if (pNew == 0)
return E_OUTOFMEMORY;
OLECHAR *pwszUser = GetCaller();
if (pwszUser)
{
Fire_OnNewUser(pwszUser);
ALock();
pNew->pwszUser = pwszUser;
if (pNew->pItf = pEventSink)
pEventSink->AddRef();
pNew->pNext = m_pHeadListeners;
if (m_pHeadListeners)
m_pHeadListeners->pPrev = pNew;
pNew->pPrev = 0;
m_pHeadListeners = pNew;
AUnlock();
}
else
{
delete pNew;
return E_OUTOFMEMORY;
}
*pdwReg = reinterpret_cast<DWORD>(pNew);
return hr;
}
STDMETHODIMP
ChatSession::Unadvise(DWORD dwReg)
{
if (dwReg == 0)
return E_INVALIDARG;
HRESULT hr = S_OK;
LISTENER *pThisNode = reinterpret_cast<LISTENER *>(dwReg);
ALock();
if (pThisNode->pPrev)
pThisNode->pPrev->pNext = pThisNode->pNext;
else
m_pHeadListeners = pThisNode->pNext;
if (pThisNode->pNext)
pThisNode->pNext->pPrev = pThisNode->pPrev;
if (pThisNode->pItf)
pThisNode->pItf->Release();
OLECHAR *pwszUser = pThisNode->pwszUser;
delete pThisNode;
AUnlock();
Fire_OnUserLeft(pwszUser);
CoTaskMemFree(pwszUser);
return hr;
}
// class StatementEnumerator ///////////////////
StatementEnumerator::StatementEnumerator(ChatSession *pThis)
: m_cRef(0),
m_pThis(pThis),
m_cursor(pThis->m_statements.begin())
{
m_pThis->AddRef();
InitializeCriticalSection(&m_csLock);
}
StatementEnumerator::~StatementEnumerator(void)
{
m_pThis->Release();
DeleteCriticalSection(&m_csLock);
}
// lock helpers (note that ChatSession is locked
// 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<IEnumString*>(this);
else if (riid == IID_IEnumString)
*ppv = static_cast<IEnumString*>(this);
else
return (*ppv = 0), E_NOINTERFACE;
reinterpret_cast<IUnknown*>(*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<OLECHAR*>(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<IChatSessionManager*>(this);
else if (riid == IID_IChatSessionManager)
*ppv = static_cast<IChatSessionManager*>(this);
else if (riid == IID_IExternalConnection)
*ppv = static_cast<IExternalConnection*>(this);
else
return (*ppv = 0), E_NOINTERFACE;
reinterpret_cast<IUnknown*>(*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<IExternalConnection*>(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(
pair<wstring,
ChatSession*>(pwszSessionName,
pNew));
(*ppcs = pNew)->AddRef();
hr = S_OK;
}
else
hr = E_OUTOFMEMORY;
}
}
else
{
(*ppcs = (*it).second)->AddRef();
hr = S_OK;
}
Unlock();
CoTaskMemFree(pwszUser);
return hr;
}
STDMETHODIMP
ChatSessionClass::DeleteSession(const OLECHAR *pwszSessionName)
{
if (pwszSessionName == 0)
return E_INVALIDARG;
HRESULT hr = E_FAIL;
OLECHAR *pwszUser = GetCaller();
if (CheckAccess(pwszUser))
{
Lock();
SESSIONMAP::iterator it
= m_sessions.find(pwszSessionName);
if (it == m_sessions.end())
{
hr = E_FAIL;
}
else
{
(*it).second->Disconnect();
(*it).second->Release();
m_sessions.erase(it);
hr = S_OK;
}
Unlock();
}
else
hr = E_ACCESSDENIED;
CoTaskMemFree(pwszUser);
return hr;
}
// class SessionNamesEnumerator
vector<wstring>&
SessionNamesEnumerator::Strings(void)
{
if (m_pStrings)
return *m_pStrings;
else
return *(m_pCloneSource->m_pStrings);
}
void
SessionNamesEnumerator::Lock(void)
{
EnterCriticalSection(&m_csLock);
}
void
SessionNamesEnumerator::Unlock(void)
{
LeaveCriticalSection(&m_csLock);
}
SessionNamesEnumerator::SessionNamesEnumerator(
ChatSessionClass *pSessionClass)
: m_cRef(0),
m_pStrings(0),
m_pCloneSource(0)
{
typedef ChatSessionClass::SESSIONMAP::iterator iterator;
ChatSessionClass::SESSIONMAP &sessions
= pSessionClass->m_sessions;
m_pStrings = new vector<wstring>;
pSessionClass->Lock();
for (iterator it = sessions.begin();
it != sessions.end();
it++)
{
m_pStrings->push_back((*it).first);
}
pSessionClass->Unlock();
m_cursor = Strings().begin();
InitializeCriticalSection(&m_csLock);
}
SessionNamesEnumerator::SessionNamesEnumerator(
SessionNamesEnumerator *pCloneSource)
: m_cRef(0),
m_pStrings(0),
m_pCloneSource(pCloneSource)
{
m_pCloneSource->AddRef();
m_cursor = Strings().begin();
InitializeCriticalSection(&m_csLock);
}
SessionNamesEnumerator::~SessionNamesEnumerator(void)
{
if (m_pCloneSource)
m_pCloneSource->Release();
else if (m_pStrings)
delete m_pStrings;
DeleteCriticalSection(&m_csLock);
}
// IUnknown methods
STDMETHODIMP
SessionNamesEnumerator::QueryInterface(REFIID riid, void **ppv)
{
if (riid == IID_IUnknown)
*ppv = static_cast<IEnumString*>(this);
else if (riid == IID_IEnumString)
*ppv = static_cast<IEnumString*>(this);
else
return (*ppv = 0), E_NOINTERFACE;
reinterpret_cast<IUnknown*>(*ppv)->AddRef();
return S_OK;
}
STDMETHODIMP_(ULONG)
SessionNamesEnumerator::AddRef(void)
{
ModuleLock();
return InterlockedIncrement(&m_cRef);
}
STDMETHODIMP_(ULONG)
SessionNamesEnumerator::Release(void)
{
LONG res = InterlockedDecrement(&m_cRef);
if (res == 0)
delete this;
ModuleUnlock();
return res;
}
// IEnumString methods
STDMETHODIMP
SessionNamesEnumerator::Next(ULONG cElems, OLECHAR **rgElems,
ULONG *pcFetched)
{
if (cElems > 1 && pcFetched == 0)
return E_INVALIDARG;
ULONG cActual = 0;
vector<wstring> &rstrings = Strings();
Lock();
while (cActual < cElems
&& m_cursor != rstrings.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 (cActual)
*pcFetched = cActual;
return cActual == cElems ? S_OK : S_FALSE;
}
STDMETHODIMP
SessionNamesEnumerator::Skip(ULONG cElems)
{
ULONG cActual = 0;
vector<wstring> &rstrings = Strings();
Lock();
while (cActual < cElems
&& m_cursor != rstrings.end())
{
m_cursor++;
cActual++;
}
Unlock();
return cActual == cElems ? S_OK : S_FALSE;
}
STDMETHODIMP
SessionNamesEnumerator::Reset(void)
{
Lock();
m_cursor = Strings().begin();
Unlock();
return S_OK;
}
STDMETHODIMP
SessionNamesEnumerator::Clone(IEnumString **ppes)
{
if (ppes == 0)
return E_INVALIDARG;
SessionNamesEnumerator *pCloneSource = m_pCloneSource;
if (pCloneSource == 0) // we are the source
m_pCloneSource = this;
*ppes = new SessionNamesEnumerator(pCloneSource);
if (*ppes)
{
(*ppes)->AddRef();
return S_OK;
}
return E_OUTOFMEMORY;
}
svc.cpp
///////////////////////////////////////////////////////
// svc.cpp
//
// Copyright 1997, Don Box/Addison Wesley
//
// This code accompanies the book "The Component
// Object Model" from Addison Wesley. Blah blah blah
//
//
#define _WIN32_WINNT 0x403
#include <windows.h>
#include <olectl.h>
#include <initguid.h>
#include <iaccess.h>
#include «ChatSession.h»
#include «../include/COMChat_i.c»
#if !defined(HAVE_IID_IACCESSCONTROL)
// there is a common bug is the SDK headers and libs
// that causes IID_IAccessControl to be undefined.
// We define it here to give the GUID linkage.
DEFINE_GUID(IID_IAccessControl,0xEEDD23E0, 0x8410, 0x11CE,
0xA1, 0xC3, 0x08, 0x00, 0x2B, 0x2B, 0x8D, 0x8F);
#endif
// standard MTA lifetime management helpers
HANDLE g_heventDone = CreateEvent(0, TRUE, FALSE, 0);
void ModuleLock(void)
{
CoAddRefServerProcess();
}
void ModuleUnlock(void)
{
if (CoReleaseServerProcess() == 0)
SetEvent(g_heventDone);
}
// standard self-registration table
const char *g_RegTable[][3] = {
{ «CLSID\\{5223A053-2441-11d1-AF4F-0060976AA886}»,
0, «ChatSession» },
{ «CLSID\\{5223A053-2441-11d1-AF4F-0060976AA886}»,
«AppId», «{5223A054-2441-11d1-AF4F-0060976AA886}»
},
{ «CLSID\\{5223A053-2441-11d1-AF4F-0060976AA886}\\LocalServer32»,
0, (const char*)-1 // rogue value indicating file name
},
{ «AppID\\{5223A054-2441-11d1-AF4F-0060976AA886}»,
0, «ChatSession Server» },
{ «AppID\\{5223A054-2441-11d1-AF4F-0060976AA886}»,
«RunAs», «Domain\\ReplaceMe»
},
{ «AppID\\{5223A054-2441-11d1-AF4F-0060976AA886}»,
«Chat Admins Group», «Domain\\ReplaceMe»
},
{ «AppID\\{5223A054-2441-11d1-AF4F-0060976AA886}»,
«Chat Users Group», «Domain\\ReplaceMe»
},
{ «AppID\\COMChat.exe»,
«AppId», «{5223A054-2441-11d1-AF4F-0060976AA886}»
},
};
// self-unregistration routine
STDAPI UnregisterServer(void) {
HRESULT hr = S_OK;
int nEntries = sizeof(g_RegTable)/sizeof(*g_RegTable);
for (int i = nEntries – 1; i >= 0; i–){
const char *pszKeyName = g_RegTable[i][0];
long err = RegDeleteKeyA(HKEY_CLASSES_ROOT, pszKeyName);
if (err != ERROR_SUCCESS)
hr = S_FALSE;
}
return hr;
}
// self-registration routine
STDAPI RegisterServer(HINSTANCE hInstance = 0) {
HRESULT hr = S_OK;
// look up server's file name
char szFileName[MAX_PATH];
GetModuleFileNameA(hInstance, szFileName, MAX_PATH);
// register entries from table
int nEntries = sizeof(g_RegTable)/sizeof(*g_RegTable);
for (int i = 0; SUCCEEDED(hr) && i < nEntries; i++) {
const char *pszKeyName = g_RegTable[i][0];
const char *pszValueName = g_RegTable[i][1];
const char *pszValue = g_RegTable[i][2];
// map rogue value to module file name
if (pszValue == (const char*)-1)
pszValue = szFileName;
HKEY hkey;
// create the key
long err = RegCreateKeyA(HKEY_CLASSES_ROOT,
pszKeyName, &hkey);
if (err == ERROR_SUCCESS) {
// set the value
err = RegSetValueExA(hkey, pszValueName, 0,
REG_SZ, (const BYTE*)pszValue,
(strlen(pszValue) + 1));
RegCloseKey(hkey);
}
if (err != ERROR_SUCCESS) {
// if cannot add key or value, back out and fail
UnregisterServer();
hr = SELFREG_E_CLASS;
}
}
return hr;
}
// these point to standard access control objects
// used to protect particular methods
IAccessControl *g_pacUsers = 0;
IAccessControl *g_pacAdmins = 0;
// this routine is called at process init time
// to build access control objects and to allow
// anonymous access to server by default
HRESULT InitializeApplicationSecurity(void)
{
// load groupnames from registry
static OLECHAR wszAdminsGroup[1024];
static OLECHAR wszUsersGroup[1024];
HKEY hkey;
long err = RegOpenKeyEx(HKEY_CLASSES_ROOT,
__TEXT(«AppID\\{5223A054-2441-11d1-AF4F-0060976AA886}»),
0, KEY_QUERY_VALUE,
&hkey);
if (err == ERROR_SUCCESS)
{
DWORD cb = sizeof(wszAdminsGroup);
err = RegQueryValueExW(hkey, L"Chat Admins Group",
0, 0, (BYTE*)wszAdminsGroup,
&cb);
cb = sizeof(wszAdminsGroup);
if (err == ERROR_SUCCESS)
err = RegQueryValueExW(hkey,
L"Chat Users Group",
0, 0, (BYTE*)wszUsersGroup,
&cb);
RegCloseKey(hkey);
}
if (err != ERROR_SUCCESS)
return MAKE_HRESULT(SEVERITY_ERROR, FACILITY_WIN32,
GetLastError());
// declare vectors of user/groups for 2 access
// control objects
ACTRL_ACCESS_ENTRYW rgaaeUsers[] = {
{ {0, NO_MULTIPLE_TRUSTEE, TRUSTEE_IS_NAME,
TRUSTEE_IS_GROUP, wszUsersGroup },
ACTRL_ACCESS_ALLOWED, COM_RIGHTS_EXECUTE, 0,
NO_INHERITANCE, 0 },
};
ACTRL_ACCESS_ENTRY_LISTW aaelUsers = {
sizeof(rgaaeUsers)/sizeof(*rgaaeUsers),
rgaaeUsers
};
ACTRL_PROPERTY_ENTRYW apeUsers = { 0, &aaelUsers, 0 };
ACTRL_ACCESSW aaUsers = { 1, &apeUsers };
ACTRL_ACCESS_ENTRYW rgaaeAdmins[] = {
{ {0, NO_MULTIPLE_TRUSTEE, TRUSTEE_IS_NAME,
TRUSTEE_IS_GROUP, wszAdminsGroup },
ACTRL_ACCESS_ALLOWED, COM_RIGHTS_EXECUTE, 0,
NO_INHERITANCE, 0 },
};
ACTRL_ACCESS_ENTRY_LISTW aaelAdmins = {
sizeof(rgaaeAdmins)/sizeof(*rgaaeAdmins),
rgaaeAdmins
};
ACTRL_PROPERTY_ENTRYW apeAdmins = { 0, &aaelAdmins, 0 };
ACTRL_ACCESSW aaAdmins = { 1, &apeAdmins };
HRESULT hr = CoInitializeSecurity(0, -1, 0, 0,
RPC_C_AUTHN_LEVEL_NONE,
RPC_C_IMP_LEVEL_ANONYMOUS,
0,
EOAC_NONE,
0);
if (SUCCEEDED(hr))
{
hr = CoCreateInstance(CLSID_DCOMAccessControl,
0, CLSCTX_ALL, IID_IAccessControl,
(void**)&g_pacUsers);
if (SUCCEEDED(hr))
hr = g_pacUsers->SetAccessRights(&aaUsers);
if (SUCCEEDED(hr))
{
hr = CoCreateInstance(CLSID_DCOMAccessControl,
0, CLSCTX_ALL,
IID_IAccessControl,
(void**)&g_pacAdmins);
if (SUCCEEDED(hr))
hr = g_pacAdmins->SetAccessRights(&aaAdmins);
}
if (FAILED(hr))
{
if (g_pacAdmins)
{
g_pacAdmins->Release();
g_pacAdmins = 0;
}
if (g_pacUsers)
{
g_pacUsers->Release();
g_pacUsers = 0;
}
}
}
return hr;
}
// the main thread routine that simply registers the class
// object and waits to die
int WINAPI WinMain(HINSTANCE, HINSTANCE,
LPSTR szCmdParam, int)
{
const TCHAR *pszPrompt =
__TEXT("Ensure that you have properly ")
__TEXT("configured the application to ")
__TEXT("run as a particular user and that ")
__TEXT("you have manually changed the ")
__TEXT("Users and Admins Group registry ")
__TEXT(«settings under this server's AppID.»);
HRESULT hr = CoInitializeEx(0, COINIT_MULTITHREADED);
if (FAILED(hr))
return hr;
// look for self-registration flags
if (strstr(szCmdParam, «/UnregServer») != 0
|| strstr(szCmdParam, «-UnregServer») != 0)
{
hr = UnregisterServer();
CoUninitialize();
return hr;
}
else if (strstr(szCmdParam, «/RegServer») != 0
|| strstr(szCmdParam, «-RegServer») != 0)
{
hr = RegisterServer();
MessageBox(0, pszPrompt, __TEXT(«COMChat»),
MB_SETFOREGROUND);
CoUninitialize();
return hr;
}
// set up process security
hr = InitializeApplicationSecurity();
if (SUCCEEDED(hr))
{
// register class object and wait to die
DWORD dwReg;
static ChatSessionClass cmc;
hr = CoRegisterClassObject(CLSID_ChatSession,
static_cast<IExternalConnection*>(&cmc),
CLSCTX_LOCAL_SERVER
REGCLS_SUSPENDED|REGCLS_MULTIPLEUSE,
&dwReg);
if (SUCCEEDED(hr))
{
hr = CoResumeClassObjects();
if (SUCCEEDED(hr))
WaitForSingleObject(g_heventDone, INFINITE);
CoRevokeClassObject(dwReg);
}
g_pacUsers->Release();
g_pacAdmins->Release();
}
if (FAILED(hr))
MessageBox(0, pszPrompt, __TEXT(«Error»),
MB_SETFOREGROUND);
CoUninitialize();
return 0;
}
More Book Stuff
Source Code
COM Chat Compilable versions of the source code in Appendix B of the book.
YACL Yet another COM library. Contains the various macros and C++ classes described in the book.
IGlobalInterfaceTable Wrapper/Sample A simplification of apartment-independent pointer use.
HostHook A custom channel hook that allows you to find out the caller's and callee's network address.
APTSUR A custom surrogate that spawns distinct STA threads for each activation request.
Custom Moniker Stuff I worked with some friends on a custom moniker framework. Here is some of the 1st bits and pieces.
Yet Another COM Library (YACL) – Preview
This is my first drop. It contains a family of preprocessor macros that automate the boilerplate activities used in COM programming.
Please send comments and bug reports to cbbugs@braintrust.com
The freshest drop is always available at http://www.develop.com/dbox/yacl.zip
Design Goals (in Order)
Easily used without Wizard support
Easily kept in one's head
Modular (use only what you need and nothing else)
Extensible
Small Code
Fast Code
No DLL ever
Compiler-friendly
Platform-neutral where possible (including 16-bit Windows)
Current Feature Set
Anal-rententive Smart Pointer
Efficient and intuitive Unicode handling
Table-driven QueryInterface
Table-driven Registration
Table-driven Class management
Generic Class Factory implementation.
Preprocessor macros for de facto IUnknown implementation techniques.
Preprocessor macros for de facto module management routines.
Preprocessor macros for de facto DllXXX routines.
Preprocessor macros for de facto out-of-proc CRCO/Wait/CRCO sequence.
Planned Work
Performance/size tuning
Compiler/Platform testing
Verify ATL/MFC interoperation
Macro-ization of smart pointer for 16-bit windows
Add optional exception semantics to smart pointer
Map COM hresults/exception to C++ exceptions
Add support for IDispatch and friends
Add support for IConnectionPoint and friends
Add IEnum -> stl thunks