Дональд Бокс - Сущность технологии СОМ. Библиотека программиста

{

ULONG cActual = 0;

vector &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

#include

#include

#include

#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(&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.

APTSURA custom surrogate that spawns distinct STA threads for each activation request.

Custom Moniker StuffI 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

1 Исследование Гиги (Giga), порученное ему фирмой Microsoft, показывает, что в 1997 году рынок коммерческих компонентов, основанных на СОМ, составил 410 миллионов долларов. Ожидается, что этот рынок к 2001 году превысит 2.8 миллиарда долларов. Эти цифры не включают продукцию Microsoft.