SRVCHILD.C

/******************************************************************************\ 
*       This is a part of the Microsoft Source Code Samples.  
*       Copyright 1992 - 1997 Microsoft Corporation. 
*       All rights reserved.  
*       This source code is only intended as a supplement to  
*       Microsoft Development Tools and/or WinHelp documentation. 
*       See these sources for detailed information regarding the  
*       Microsoft samples programs. 
\******************************************************************************/ 
 
/*++ 
 
Copyright 1992 - 1997 Microsoft Corporation 
 
Module Name: 
 
    SrvChild.c 
 
Abstract: 
 
    The server component of Remote. It spawns a child process 
    and redirects the stdin/stdout/stderr of child to itself. 
    Waits for connections from clients - passing the 
    output of child process to client and the input from clients 
    to child process. 
 
Author: 
 
    Rajivendra Nath  2-Jan-1992 
    Dave Hart        30 May 1997 split from Server.c 
 
Environment: 
 
    Console App. User mode. 
 
Revision History: 
 
--*/ 
 
#include <windows.h> 
#include <stdio.h> 
#include <stdlib.h> 
#include <process.h> 
#include <io.h> 
#include <string.h> 
#include "Remote.h" 
#include "Server.h" 
 
 
VOID 
FASTCALL 
StartChildOutPipeRead( 
    VOID 
    ) 
{ 
    ReadChildOverlapped.OffsetHigh = 
        ReadChildOverlapped.Offset = 0; 
 
    if ( ! ReadFileEx( 
               hReadChildOutput, 
               ReadChildBuffer, 
               sizeof(ReadChildBuffer) - 1,                  // allow for null term 
               &ReadChildOverlapped, 
               ReadChildOutputCompleted 
               )) { 
 
        if (INVALID_HANDLE_VALUE != hWriteChildStdIn) { 
 
            CANCELIO( hWriteChildStdIn ); 
            CloseHandle( hWriteChildStdIn ); 
            hWriteChildStdIn = INVALID_HANDLE_VALUE; 
        } 
    } 
} 
 
 
VOID 
WINAPI 
ReadChildOutputCompleted( 
    DWORD dwError, 
    DWORD cbRead, 
    LPOVERLAPPED lpO 
    ) 
{ 
    UNREFERENCED_PARAMETER(lpO); 
 
    // 
    // We can get called after hWriteTempFile 
    // is closed after the child has exited. 
    // 
 
    if (! dwError && 
        INVALID_HANDLE_VALUE != hWriteTempFile) { 
 
        // 
        // Start a write to the temp file. 
        // 
 
        ReadChildOverlapped.OffsetHigh = 0; 
        ReadChildOverlapped.Offset = dwWriteFilePointer; 
 
        if ( ! WriteFileEx( 
                   hWriteTempFile, 
                   ReadChildBuffer, 
                   cbRead, 
                   &ReadChildOverlapped, 
                   WriteTempFileCompleted 
                   )) { 
 
            dwError = GetLastError(); 
 
            if (ERROR_DISK_FULL == dwError) { 
 
                printf("Remote: disk full writing temp file %s, exiting\n", SaveFileName); 
 
                if (INVALID_HANDLE_VALUE != hWriteChildStdIn) { 
 
                    CANCELIO( hWriteChildStdIn ); 
                    CloseHandle( hWriteChildStdIn ); 
                    hWriteChildStdIn = INVALID_HANDLE_VALUE; 
                } 
 
            } else { 
 
                ErrorExit("WriteFileEx for temp file failed."); 
            } 
        } 
    } 
} 
 
 
VOID 
WINAPI 
WriteTempFileCompleted( 
    DWORD dwError, 
    DWORD cbWritten, 
    LPOVERLAPPED lpO 
    ) 
{ 
    UNREFERENCED_PARAMETER(lpO); 
 
    if (dwError) { 
 
        if (ERROR_DISK_FULL == dwError) { 
 
            printf("Remote: disk full writing temp file %s, exiting\n", SaveFileName); 
 
            if (INVALID_HANDLE_VALUE != hWriteChildStdIn) { 
 
                CANCELIO( hWriteChildStdIn ); 
                CloseHandle( hWriteChildStdIn ); 
                hWriteChildStdIn = INVALID_HANDLE_VALUE; 
            } 
 
            return; 
 
        } else { 
 
            SetLastError(dwError); 
            ErrorExit("WriteTempFileCompleted may need work"); 
        } 
    } 
 
    dwWriteFilePointer += cbWritten; 
 
    TRACE(CHILD, ("Wrote %d bytes to temp file\n", cbWritten)); 
 
    StartServerToClientFlow(); 
 
    // 
    // Start another read against the child input. 
    // 
 
    StartChildOutPipeRead(); 
}