Tricks of the Windows Gam…ming Gurus (2nd Edition)/Disc2.iso/msdn_vcb/samples/vc98/sdk/com/dcom/simple/sclient.cpp

C/C++ Source or Header | 1996-07-06 | 6.0 KB | 178 lines

// ===========================================================================
// File: S C L I E N T . C P P
//
// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF
// ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO
// THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A
// PARTICULAR PURPOSE.
//
// Description:
//
//  This is the client-portion of the SIMPLE Distributed COM sample. This
// application uses the CLSID_SimpleObject class implemented by the SSERVER.CPP
// module. Pass the machine-name to instantiate the object on, or pass no
// arguments to instantiate the object on the same machine. See the comments
// in SSERVER.CPP for further details.
//
//  The purpose of this sample is to demonstrate what is minimally required
// to use a COM object, whether it runs on the same machine or on a different
// machine.
//
// Instructions:
//
//  To use this sample:
//   * build it using the NMAKE command. NMAKE will create SSERVER.EXE and
//     SCLIENT.EXE.
//   * install the SSERVER.EXE on the current machine or on a remote machine
//     according to the installation instructions found in SSERVER.CPP.
//   * run SCLIENT.EXE. use no command-line arguments to instantiate the object
//     on the current machine. use a single command-line argument of the remote
//     machine-name (UNC or DNS) to instantiate the object on a remote machine.
//   * SCLIENT.EXE displays some simple information about the calls it is
//     making on the object.
//
// Copyright 1996 Microsoft Corporation.  All Rights Reserved.
// ===========================================================================

// %%Includes: ---------------------------------------------------------------
#define INC_OLE2
#include <stdio.h>
#include <windows.h>
#include <initguid.h>
#include <tchar.h>
#include <conio.h>

// %%GUIDs: ------------------------------------------------------------------
DEFINE_GUID(CLSID_SimpleObject, 0x5e9ddec7, 0x5767, 0x11cf, 0xbe, 0xab, 0x0, 0xaa, 0x0, 0x6c, 0x36, 0x6);

// %%Constants: --------------------------------------------------------------
const ULONG cbDefault = 4096;    // default # of bytes to Read/Write

// ---------------------------------------------------------------------------
// %%Function: Message
//
//  Formats and displays a message to the console.
// ---------------------------------------------------------------------------
 void
Message(LPTSTR szPrefix, HRESULT hr)
{
    LPTSTR   szMessage;

    if (hr == S_OK)
        {
        wprintf(szPrefix);
        return;
        }

    if (HRESULT_FACILITY(hr) == FACILITY_WINDOWS)
        hr = HRESULT_CODE(hr);

    FormatMessage(
        FORMAT_MESSAGE_ALLOCATE_BUFFER |
        FORMAT_MESSAGE_FROM_SYSTEM,
        NULL,
        hr,
        MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), //The user default language
        (LPTSTR)&szMessage,
        0,
        NULL);

    wprintf(TEXT("%s: %s(%lx)\n"), szPrefix, szMessage, hr);

    LocalFree(szMessage);
}  // Message

// ---------------------------------------------------------------------------
// %%Function: OutputTime
// ---------------------------------------------------------------------------
 void
OutputTime(LARGE_INTEGER* pliStart, LARGE_INTEGER* pliFinish)
{
    LARGE_INTEGER liFreq;

    QueryPerformanceFrequency(&liFreq);
    wprintf(TEXT("%0.4f seconds\n"),
        (float)(pliFinish->LowPart - pliStart->LowPart)/(float)liFreq.LowPart);
}  // OutputTime

// ---------------------------------------------------------------------------
// %%Function: main
// ---------------------------------------------------------------------------
 void __cdecl
main(int argc, CHAR **argv)
{
    HRESULT hr;
    MULTI_QI    mq;
    COSERVERINFO csi, *pcsi=NULL;
    WCHAR wsz [MAX_PATH];
    ULONG cb = cbDefault;
    LARGE_INTEGER liStart, liFinish;

    // allow a machine-name as the command-line argument
    if (argc > 1)
        {
        MultiByteToWideChar(CP_ACP, MB_PRECOMPOSED, argv[1], -1,
            wsz, MAX_PATH);
        memset(&csi, 0, sizeof(COSERVERINFO));
        csi.pwszName = wsz;
        pcsi = &csi;
        }

    // allow a byte-size to be passed on the command-line
    if (argc > 2)
        cb = atol(argv[2]);

    // initialize COM for free-threaded use
    hr = CoInitializeEx(NULL, COINIT_MULTITHREADED);
    if (FAILED(hr))
        {
        Message(TEXT("Client: CoInitializeEx"), hr);
        exit(hr);
        }

    // create a remote instance of the object on the argv[1] machine
    Message(TEXT("Client: Creating Instance..."), S_OK);
    mq.pIID = &IID_IStream;
    mq.pItf = NULL;
    mq.hr = S_OK;
    QueryPerformanceCounter(&liStart);
    hr = CoCreateInstanceEx(CLSID_SimpleObject, NULL, CLSCTX_SERVER, pcsi, 1, &mq);
    QueryPerformanceCounter(&liFinish);
    OutputTime(&liStart, &liFinish);

    if (FAILED(hr))
        Message(TEXT("Client: CoCreateInstanceEx"), hr);
    else
        {
        LPSTREAM    pstm = (IStream*)mq.pItf;
        LPVOID      pv;

        // "read" some data from the object
        Message(TEXT("Client: Reading data..."), S_OK);
        pv = CoTaskMemAlloc(cb);
        QueryPerformanceCounter(&liStart);
        hr = pstm->Read(pv, cb, NULL);
        QueryPerformanceCounter(&liFinish);
        OutputTime(&liStart, &liFinish);
        if (FAILED(hr))
            Message(TEXT("Client: IStream::Read"), hr);

        // "write" some data to the object
        Message(TEXT("Client: Writing data..."), S_OK);
        QueryPerformanceCounter(&liStart);
        hr = pstm->Write(pv, cb, NULL);
        QueryPerformanceCounter(&liFinish);
        OutputTime(&liStart, &liFinish);
        if (FAILED(hr))
            Message(TEXT("Client: IStream::Write"), hr);

        // let go of the object
        pstm->Release();
        }

    CoUninitialize();
    Message(TEXT("Client: Done"), S_OK);
}  // main

// EOF =======================================================================