/* 

 * stub16.c 

 *

 *	A helper program used for running 16-bit DOS applications under

 *	Windows 95.

 *

 * Copyright (c) 1996 by Sun Microsystems, Inc.

 *

 * See the file "license.terms" for information on usage and redistribution

 * of this file, and for a DISCLAIMER OF ALL WARRANTIES.

 *

 * RCS: @(#) $Id: stub16.c,v 1.4 1999/04/21 21:50:34 rjohnson Exp $

 */

#define STRICT

#include <windows.h>

#include <stdio.h>

static HANDLE		CreateTempFile(void);

/*

 *---------------------------------------------------------------------------

 *

 * main

 *

 *	Entry point for the 32-bit console mode app used by Windows 95 to

 *	help run the 16-bit program specified on the command line.

 *

 *	1. EOF on a pipe that connects a detached 16-bit process and a

 *	32-bit process is never seen.  So, this process runs the 16-bit

 *	process _attached_, and then it is run detached from the calling

 *	32-bit process.  

 * 

 *	2. If a 16-bit process blocks reading from or writing to a pipe,

 *	it never wakes up, and eventually brings the whole system down

 *	with it if you try to kill the process.  This app simulates

 *	pipes.  If any of the stdio handles is a pipe, this program

 *	accumulates information into temp files and forwards it to or

 *	from the DOS application as appropriate.  This means that this

 *	program must receive EOF from a stdin pipe before it will actually

 *	start the DOS app, and the DOS app must finish generating stdout

 *	or stderr before the data will be sent to the next stage of the

 *	pipe.  If the stdio handles are not pipes, no accumulation occurs

 *	and the data is passed straight through to and from the DOS

 *	application.

 *

 * Results:

 *	None.

 *

 * Side effects:

 *	The child process is created and this process waits for it to

 *	complete.

 *

 *---------------------------------------------------------------------------

 */

int

main()

{

    DWORD dwRead, dwWrite;

    char *cmdLine;

    HANDLE hStdInput, hStdOutput, hStdError;

    HANDLE hFileInput, hFileOutput, hFileError;

    STARTUPINFO si;

    PROCESS_INFORMATION pi;

    char buf[8192];

    DWORD result;

    hFileInput = INVALID_HANDLE_VALUE;

    hFileOutput = INVALID_HANDLE_VALUE;

    hFileError = INVALID_HANDLE_VALUE;

    result = 1;

    /*

     * Don't get command line from argc, argv, because the command line

     * tokenizer will have stripped off all the escape sequences needed

     * for quotes and backslashes, and then we'd have to put them all

     * back in again.  Get the raw command line and parse off what we

     * want ourselves.  The command line should be of the form:

     *

     * stub16.exe program arg1 arg2 ...

     */

    cmdLine = strchr(GetCommandLine(), ' ');

    if (cmdLine == NULL) {

	return 1;

    }

    cmdLine++;

    hStdInput = GetStdHandle(STD_INPUT_HANDLE);

    hStdOutput = GetStdHandle(STD_OUTPUT_HANDLE);

    hStdError = GetStdHandle(STD_ERROR_HANDLE);

    if (GetFileType(hStdInput) == FILE_TYPE_PIPE) {

	hFileInput = CreateTempFile();

	if (hFileInput == INVALID_HANDLE_VALUE) {

	    goto cleanup;

	}

	while (ReadFile(hStdInput, buf, sizeof(buf), &dwRead, NULL) != FALSE) {

	    if (dwRead == 0) {

		break;

	    }

	    if (WriteFile(hFileInput, buf, dwRead, &dwWrite, NULL) == FALSE) {

		goto cleanup;

	    }

	}

	SetFilePointer(hFileInput, 0, 0, FILE_BEGIN);

	SetStdHandle(STD_INPUT_HANDLE, hFileInput);

    }

    if (GetFileType(hStdOutput) == FILE_TYPE_PIPE) {

	hFileOutput = CreateTempFile();

	if (hFileOutput == INVALID_HANDLE_VALUE) {

	    goto cleanup;

	}

	SetStdHandle(STD_OUTPUT_HANDLE, hFileOutput);

    }

    if (GetFileType(hStdError) == FILE_TYPE_PIPE) {

	hFileError = CreateTempFile();

	if (hFileError == INVALID_HANDLE_VALUE) {

	    goto cleanup;

	}

	SetStdHandle(STD_ERROR_HANDLE, hFileError);

    }

    ZeroMemory(&si, sizeof(si));

    si.cb = sizeof(si);

    if (CreateProcess(NULL, cmdLine, NULL, NULL, TRUE, 0, NULL, NULL, &si, 

	    &pi) == FALSE) {

	goto cleanup;

    }

    WaitForInputIdle(pi.hProcess, 5000);

    WaitForSingleObject(pi.hProcess, INFINITE);

    GetExitCodeProcess(pi.hProcess, &result);

    CloseHandle(pi.hProcess);

    CloseHandle(pi.hThread);

    if (hFileOutput != INVALID_HANDLE_VALUE) {

	SetFilePointer(hFileOutput, 0, 0, FILE_BEGIN);

	while (ReadFile(hFileOutput, buf, sizeof(buf), &dwRead, NULL) != FALSE) {

	    if (dwRead == 0) {

		break;

	    }

	    if (WriteFile(hStdOutput, buf, dwRead, &dwWrite, NULL) == FALSE) {

		break;

	    }

	}

    }

    if (hFileError != INVALID_HANDLE_VALUE) {

	SetFilePointer(hFileError, 0, 0, FILE_BEGIN);

	while (ReadFile(hFileError, buf, sizeof(buf), &dwRead, NULL) != FALSE) {

	    if (dwRead == 0) {

		break;

	    }

	    if (WriteFile(hStdError, buf, dwRead, &dwWrite, NULL) == FALSE) {

		break;

	    }

	}

    }

cleanup:

    if (hFileInput != INVALID_HANDLE_VALUE) {

	CloseHandle(hFileInput);

    }

    if (hFileOutput != INVALID_HANDLE_VALUE) {

	CloseHandle(hFileOutput);

    }

    if (hFileError != INVALID_HANDLE_VALUE) {

	CloseHandle(hFileError);

    }

    CloseHandle(hStdInput);

    CloseHandle(hStdOutput);

    CloseHandle(hStdError);

    ExitProcess(result);

    return 1;

}

static HANDLE

CreateTempFile()

{

    char name[MAX_PATH];

    SECURITY_ATTRIBUTES sa;

    if (GetTempPath(sizeof(name), name) == 0) {

	return INVALID_HANDLE_VALUE;

    }

    if (GetTempFileName(name, "tcl", 0, name) == 0) {

	return INVALID_HANDLE_VALUE;

    }

    sa.nLength = sizeof(sa);

    sa.lpSecurityDescriptor = NULL;

    sa.bInheritHandle = TRUE;

    return CreateFile(name, GENERIC_READ | GENERIC_WRITE, 0, &sa, 

	    CREATE_ALWAYS, FILE_ATTRIBUTE_TEMPORARY | FILE_FLAG_DELETE_ON_CLOSE,

	    NULL);

}