/* 
 * tclWinConsole.c --
 *
 *	This file implements the Windows-specific console functions,
 *	and the "console" channel driver.
 *
 * Copyright (c) 1999 by Scriptics Corp.
 *
 * See the file "license.terms" for information on usage and redistribution
 * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 *
 * RCS: @(#) $Id: tclWinConsole.c,v 1.9 2002/11/07 02:13:37 mdejong Exp $
 * RCS: @(#) $Id: tclWinConsole.c,v 1.10 2002/11/26 22:35:20 davygrvy Exp $
 */

#include "tclWinInt.h"

#include <fcntl.h>
#include <io.h>
#include <sys/stat.h>

				 * the current buffer to be written. */
    HANDLE readable;		/* Manual-reset event to signal when the
				 * reader thread has finished waiting for
				 * input. */
    HANDLE startWriter;		/* Auto-reset event used by the main thread to
				 * signal when the writer thread should attempt
				 * to write to the console. */
    HANDLE stopWriter;		/* Auto-reset event used by the main thread to
				 * signal when the writer thread should exit.
				 */
    HANDLE startReader;		/* Auto-reset event used by the main thread to
				 * signal when the reader thread should attempt
				 * to read from the console. */
    HANDLE stopReader;		/* Auto-reset event used by the main thread to
				 * signal when the reader thread should exit.
				 */
    DWORD writeError;		/* An error caused by the last background
				 * write.  Set to 0 if no error has been
				 * detected.  This word is shared with the
				 * writer thread so access must be
				 * synchronized with the writable object.
				 */
    char *writeBuf;		/* Current background output buffer.

    ClientData instanceData,	/* Pointer to ConsoleInfo structure. */
    Tcl_Interp *interp)		/* For error reporting. */
{
    ConsoleInfo *consolePtr = (ConsoleInfo *) instanceData;
    int errorCode;
    ConsoleInfo *infoPtr, **nextPtrPtr;
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
    DWORD exitCode;

    errorCode = 0;
    
    /*
     * Clean up the background thread if necessary.  Note that this
     * must be done before we can close the file, since the 
     * thread may be blocking trying to read from the console.
     */
    
    if (consolePtr->readThread) {

	/*
	 * The thread may already have closed on it's own.  Check it's
	 * exit code.
	 */
	 * Forcibly terminate the background thread.  We cannot rely on the
	 * thread to cleanly terminate itself because we have no way of
	 * closing the handle without blocking in the case where the
	 * thread is in the middle of an I/O operation.  Note that we need
	 * to guard against terminating the thread while it is in the
	 * middle of Tcl_ThreadAlert because it won't be able to release
	 * the notifier lock.
	 */

	GetExitCodeThread(consolePtr->readThread, &exitCode);

	if (exitCode == STILL_ACTIVE) {

	    /*
	     * Set the stop event so that if the reader thread is blocked
	     * in ConsoleReaderThread on WaitForMultipleEvents, it will exit
	     * cleanly.
	     */

	    SetEvent(consolePtr->stopReader);

	    /*
	     * Wait at most 20 milliseconds for the reader thread to close.
	     */

	    if (WaitForSingleObject(consolePtr->readThread, 20)
		    == WAIT_TIMEOUT) {
		/*
		 * Forcibly terminate the background thread as a last
		 * resort.  Note that we need to guard against
		 * terminating the thread while it is in the middle of
		 * Tcl_ThreadAlert because it won't be able to release
		 * the notifier lock.
		 */

	Tcl_MutexLock(&consoleMutex);
	TerminateThread(consolePtr->readThread, 0);

		Tcl_MutexLock(&consoleMutex);

		/* BUG: this leaks memory. */
		TerminateThread(consolePtr->readThread, 0);
		Tcl_MutexUnlock(&consoleMutex);
	    }
	/*
	 * Wait for the thread to terminate.  This ensures that we are
	 * completely cleaned up before we leave this function. 
	 */

	}
	WaitForSingleObject(consolePtr->readThread, INFINITE);
	Tcl_MutexUnlock(&consoleMutex);

	CloseHandle(consolePtr->readThread);
	CloseHandle(consolePtr->readable);
	CloseHandle(consolePtr->startReader);
	CloseHandle(consolePtr->stopReader);
	consolePtr->readThread = NULL;
    }
    consolePtr->validMask &= ~TCL_READABLE;

    /*
     * Wait for the writer thread to finish the current buffer, then
     * terminate the thread and close the handles.  If the channel is
     * nonblocking, there should be no pending write operations.
     */
    
    if (consolePtr->writeThread) {
	if (consolePtr->toWrite) {
	    /*
	     * We only need to wait if there is something to write.
	     * This may prevent infinite wait on exit. [python bug 216289]
	     */
	    WaitForSingleObject(consolePtr->writable, INFINITE);
	}

	/*
	 * The thread may already have closed on it's own.  Check it's
	 * exit code.
	 */
	 * Forcibly terminate the background thread.  We cannot rely on the
	 * thread to cleanly terminate itself because we have no way of
	 * closing the handle without blocking in the case where the
	 * thread is in the middle of an I/O operation.  Note that we need
	 * to guard against terminating the thread while it is in the
	 * middle of Tcl_ThreadAlert because it won't be able to release
	 * the notifier lock.
	 */

	GetExitCodeThread(consolePtr->writeThread, &exitCode);

	if (exitCode == STILL_ACTIVE) {
	    /*
	     * Set the stop event so that if the reader thread is blocked
	     * in ConsoleWriterThread on WaitForMultipleEvents, it will
	     * exit cleanly.
	     */

	    SetEvent(consolePtr->stopWriter);

	    /*
	     * Wait at most 20 milliseconds for the writer thread to close.
	     */

	    if (WaitForSingleObject(consolePtr->writeThread, 20)
		    == WAIT_TIMEOUT) {
		/*
		 * Forcibly terminate the background thread as a last
		 * resort.  Note that we need to guard against
		 * terminating the thread while it is in the middle of
		 * Tcl_ThreadAlert because it won't be able to release
		 * the notifier lock.
		 */

	Tcl_MutexLock(&consoleMutex);
	TerminateThread(consolePtr->writeThread, 0);

		Tcl_MutexLock(&consoleMutex);
		TerminateThread(consolePtr->writeThread, 0);
		Tcl_MutexUnlock(&consoleMutex);
	    }
	/*
	 * Wait for the thread to terminate.  This ensures that we are
	 * completely cleaned up before we leave this function. 
	 */

	}
	WaitForSingleObject(consolePtr->writeThread, INFINITE);
	Tcl_MutexUnlock(&consoleMutex);

	CloseHandle(consolePtr->writeThread);
	CloseHandle(consolePtr->writable);
	CloseHandle(consolePtr->startWriter);
	CloseHandle(consolePtr->stopWriter);
	consolePtr->writeThread = NULL;
    }
    consolePtr->validMask &= ~TCL_WRITABLE;


    /*
     * Don't close the Win32 handle if the handle is a standard channel

 */

static DWORD WINAPI
ConsoleReaderThread(LPVOID arg)
{
    ConsoleInfo *infoPtr = (ConsoleInfo *)arg;
    HANDLE *handle = infoPtr->handle;
    DWORD count;
    DWORD count, waitResult;
    HANDLE wEvents[2];

    /* The first event takes precedence. */
    wEvents[0] = infoPtr->stopReader;
    wEvents[1] = infoPtr->startReader;

    for (;;) {
	/*
	 * Wait for the main thread to signal before attempting to wait.
	 */

	waitResult = WaitForMultipleObjects(2, wEvents, FALSE, INFINITE);
	WaitForSingleObject(infoPtr->startReader, INFINITE);

	if (waitResult != (WAIT_OBJECT_0 + 1)) {
	    /*
	     * The start event was not signaled.  It must be the stop event
	     * or an error, so exit this thread.
	     */

	    break;
	}

	count = 0;

	/* 
	 * Look for data on the console, but first ignore any events
	 * that are not KEY_EVENTs 
	 */
	if (ReadConsole(handle, infoPtr->buffer, CONSOLE_BUFFER_SIZE,
	if (ReadConsoleA(handle, infoPtr->buffer, CONSOLE_BUFFER_SIZE,
		(LPDWORD) &infoPtr->bytesRead, NULL) != FALSE) {
	    /*
	     * Data was stored in the buffer.
	     */
	    
	    infoPtr->readFlags |= CONSOLE_BUFFERED;
	} else {

	 * this thread while we are holding a mutex in the notifier code.
	 */

	Tcl_MutexLock(&consoleMutex);
	Tcl_ThreadAlert(infoPtr->threadId);
	Tcl_MutexUnlock(&consoleMutex);
    }

    return 0;			/* NOT REACHED */
    return 0;
}

/*
 *----------------------------------------------------------------------
 *
 * ConsoleWriterThread --
 *

static DWORD WINAPI
ConsoleWriterThread(LPVOID arg)
{

    ConsoleInfo *infoPtr = (ConsoleInfo *)arg;
    HANDLE *handle = infoPtr->handle;
    DWORD count, toWrite;
    DWORD count, toWrite, waitResult;
    char *buf;
    HANDLE wEvents[2];

    /* The first event takes precedence. */
    wEvents[0] = infoPtr->stopWriter;
    wEvents[1] = infoPtr->startWriter;

    for (;;) {
	/*
	 * Wait for the main thread to signal before attempting to write.
	 */

	waitResult = WaitForMultipleObjects(2, wEvents, FALSE, INFINITE);
	WaitForSingleObject(infoPtr->startWriter, INFINITE);

	if (waitResult != (WAIT_OBJECT_0 + 1)) {
	    /*
	     * The start event was not signaled.  It must be the stop event
	     * or an error, so exit this thread.
	     */

	    break;
	}

	buf = infoPtr->writeBuf;
	toWrite = infoPtr->toWrite;

	/*
	 * Loop until all of the bytes are written or an error occurs.
	 */

	while (toWrite > 0) {
	    if (WriteFile(handle, buf, toWrite, &count, NULL) == FALSE) {
	    if (WriteConsoleA(handle, buf, toWrite, &count, NULL) == FALSE) {
		infoPtr->writeError = GetLastError();
		break;
	    } else {
		toWrite -= count;
		buf += count;
	    }
	}

	 * this thread while we are holding a mutex in the notifier code.
	 */

	Tcl_MutexLock(&consoleMutex);
	Tcl_ThreadAlert(infoPtr->threadId);
	Tcl_MutexUnlock(&consoleMutex);
    }

    return 0;			/* NOT REACHED */
    return 0;
}



/*
 *----------------------------------------------------------------------
 *

    HANDLE handle;
    char *channelName;
    int permissions;
{
    char encoding[4 + TCL_INTEGER_SPACE];
    ConsoleInfo *infoPtr;
    ThreadSpecificData *tsdPtr;
    DWORD id;
    DWORD id, modes;

    tsdPtr = ConsoleInit();

    /*
     * See if a channel with this handle already exists.
     */
    
    infoPtr = (ConsoleInfo *) ckalloc((unsigned) sizeof(ConsoleInfo));
    memset(infoPtr, 0, sizeof(ConsoleInfo));

    infoPtr->validMask = permissions;
    infoPtr->handle = handle;

    wsprintfA(encoding, "cp%d", GetConsoleCP());
    

    /*
     * Use the pointer for the name of the result channel.
     * This keeps the channel names unique, since some may share
     * handles (stdin/stdout/stderr for instance).
     */

    wsprintfA(channelName, "file%lx", (int) infoPtr);
    
    infoPtr->channel = Tcl_CreateChannel(&consoleChannelType, channelName,
            (ClientData) infoPtr, permissions);

    infoPtr->threadId = Tcl_GetCurrentThread();

    if (permissions & TCL_READABLE) {
	/*
	 * Make sure the console input buffer is ready for only character
	 * input notifications and the buffer is set for line buffering.
	 * IOW, we only want to catch when complete lines are ready for
	 * reading.
	 */
	GetConsoleMode(infoPtr->handle, &modes);
	modes &= ~(ENABLE_WINDOW_INPUT | ENABLE_MOUSE_INPUT);
	modes |= ENABLE_LINE_INPUT;
	SetConsoleMode(infoPtr->handle, modes);

	infoPtr->readable = CreateEvent(NULL, TRUE, TRUE, NULL);
	infoPtr->startReader = CreateEvent(NULL, FALSE, FALSE, NULL);
	infoPtr->stopReader = CreateEvent(NULL, FALSE, FALSE, NULL);
	infoPtr->readThread = CreateThread(NULL, 8000, ConsoleReaderThread,
	infoPtr->readThread = CreateThread(NULL, 256, ConsoleReaderThread,
	        infoPtr, 0, &id);
	SetThreadPriority(infoPtr->readThread, THREAD_PRIORITY_HIGHEST); 
	SetThreadPriority(infoPtr->readThread, THREAD_PRIORITY_HIGHEST);
    }

    if (permissions & TCL_WRITABLE) {
	infoPtr->writable = CreateEvent(NULL, TRUE, TRUE, NULL);
	infoPtr->startWriter = CreateEvent(NULL, FALSE, FALSE, NULL);
	infoPtr->stopWriter = CreateEvent(NULL, FALSE, FALSE, NULL);
	infoPtr->writeThread = CreateThread(NULL, 8000, ConsoleWriterThread,
	infoPtr->writeThread = CreateThread(NULL, 256, ConsoleWriterThread,
	        infoPtr, 0, &id);
	SetThreadPriority(infoPtr->writeThread, THREAD_PRIORITY_HIGHEST);
    }

    /*
     * Files have default translation of AUTO and ^Z eof char, which
     * means that a ^Z will be accepted as EOF when reading.
     */
    
    Tcl_SetChannelOption(NULL, infoPtr->channel, "-translation", "auto");
    Tcl_SetChannelOption(NULL, infoPtr->channel, "-eofchar", "\032 {}");
    Tcl_SetChannelOption(NULL, infoPtr->channel, "-encoding", encoding);

    return infoPtr->channel;
}