tclwinchan.c

这是leon3处理器的交叉编译链

 */

static int
FileSeekProc(instanceData, offset, mode, errorCodePtr)
    ClientData instanceData;	/* File state. */
    long offset;		/* Offset to seek to. */
    int mode;			/* Relative to where should we seek? */
    int *errorCodePtr;		/* To store error code. */
{
    FileInfo *infoPtr = (FileInfo *) instanceData;
    DWORD moveMethod;
    DWORD newPos, newPosHigh;
    DWORD oldPos, oldPosHigh;

    *errorCodePtr = 0;
    if (mode == SEEK_SET) {
        moveMethod = FILE_BEGIN;
    } else if (mode == SEEK_CUR) {
        moveMethod = FILE_CURRENT;
    } else {
        moveMethod = FILE_END;
    }

    /*
     * Save our current place in case we need to roll-back the seek.
     */
    oldPosHigh = (DWORD)0;
    oldPos = SetFilePointer(infoPtr->handle, (LONG)0, &oldPosHigh,
	    FILE_CURRENT);
    if (oldPos == INVALID_SET_FILE_POINTER) {
	int winError = GetLastError();
	if (winError != NO_ERROR) {
	    TclWinConvertError(winError);
	    *errorCodePtr = errno;
	    return -1;
	}
    }

    newPosHigh = (DWORD)(offset < 0 ? -1 : 0);
    newPos = SetFilePointer(infoPtr->handle, (LONG) offset, &newPosHigh,
			    moveMethod);
    if (newPos == INVALID_SET_FILE_POINTER) {
	int winError = GetLastError();
	if (winError != NO_ERROR) {
	    TclWinConvertError(winError);
	    *errorCodePtr = errno;
	    return -1;
	}
    }

    /*
     * Check for expressability in our return type, and roll-back otherwise.
     */
    if (newPosHigh != 0) {
	*errorCodePtr = EOVERFLOW;
	SetFilePointer(infoPtr->handle, (LONG)oldPos, &oldPosHigh, FILE_BEGIN);
	return -1;
    }
    return (int) newPos;
}

/*
 *----------------------------------------------------------------------
 *
 * FileWideSeekProc --
 *
 *	Seeks on a file-based channel. Returns the new position.
 *
 * Results:
 *	-1 if failed, the new position if successful. If failed, it
 *	also sets *errorCodePtr to the error code.
 *
 * Side effects:
 *	Moves the location at which the channel will be accessed in
 *	future operations.
 *
 *----------------------------------------------------------------------
 */

static Tcl_WideInt
FileWideSeekProc(instanceData, offset, mode, errorCodePtr)
    ClientData instanceData;	/* File state. */
    Tcl_WideInt offset;		/* Offset to seek to. */
    int mode;			/* Relative to where should we seek? */
    int *errorCodePtr;		/* To store error code. */
{
    FileInfo *infoPtr = (FileInfo *) instanceData;
    DWORD moveMethod;
    DWORD newPos, newPosHigh;

    *errorCodePtr = 0;
    if (mode == SEEK_SET) {
        moveMethod = FILE_BEGIN;
    } else if (mode == SEEK_CUR) {
        moveMethod = FILE_CURRENT;
    } else {
        moveMethod = FILE_END;
    }

    newPosHigh = (DWORD)(offset >> 32);
    newPos = SetFilePointer(infoPtr->handle, (LONG) offset, &newPosHigh,
			    moveMethod);
    if (newPos == INVALID_SET_FILE_POINTER) {
	int winError = GetLastError();
	if (winError != NO_ERROR) {
	    TclWinConvertError(winError);
	    *errorCodePtr = errno;
	    return -1;
	}
    }
    return ((Tcl_WideInt) newPos) | (((Tcl_WideInt) newPosHigh) << 32);
}

/*
 *----------------------------------------------------------------------
 *
 * FileInputProc --
 *
 *	Reads input from the IO channel into the buffer given. Returns
 *	count of how many bytes were actually read, and an error indication.
 *
 * Results:
 *	A count of how many bytes were read is returned and an error
 *	indication is returned in an output argument.
 *
 * Side effects:
 *	Reads input from the actual channel.
 *
 *----------------------------------------------------------------------
 */

static int
FileInputProc(instanceData, buf, bufSize, errorCode)
    ClientData instanceData;		/* File state. */
    char *buf;				/* Where to store data read. */
    int bufSize;			/* How much space is available
                                         * in the buffer? */
    int *errorCode;			/* Where to store error code. */
{
    FileInfo *infoPtr;
    DWORD bytesRead;

    *errorCode = 0;
    infoPtr = (FileInfo *) instanceData;

    /*
     * Note that we will block on reads from a console buffer until a
     * full line has been entered.  The only way I know of to get
     * around this is to write a console driver.  We should probably
     * do this at some point, but for now, we just block.  The same
     * problem exists for files being read over the network.
     */

    if (ReadFile(infoPtr->handle, (LPVOID) buf, (DWORD) bufSize, &bytesRead,
            (LPOVERLAPPED) NULL) != FALSE) {
	return bytesRead;
    }
    
    TclWinConvertError(GetLastError());
    *errorCode = errno;
    if (errno == EPIPE) {
	return 0;
    }
    return -1;
}

/*
 *----------------------------------------------------------------------
 *
 * FileOutputProc --
 *
 *	Writes the given output on the IO channel. Returns count of how
 *	many characters were actually written, and an error indication.
 *
 * Results:
 *	A count of how many characters were written is returned and an
 *	error indication is returned in an output argument.
 *
 * Side effects:
 *	Writes output on the actual channel.
 *
 *----------------------------------------------------------------------
 */

static int
FileOutputProc(instanceData, buf, toWrite, errorCode)
    ClientData instanceData;		/* File state. */
    CONST char *buf;			/* The data buffer. */
    int toWrite;			/* How many bytes to write? */
    int *errorCode;			/* Where to store error code. */
{
    FileInfo *infoPtr = (FileInfo *) instanceData;
    DWORD bytesWritten;
    
    *errorCode = 0;

    /*
     * If we are writing to a file that was opened with O_APPEND, we need to
     * seek to the end of the file before writing the current buffer.
     */

    if (infoPtr->flags & FILE_APPEND) {
        SetFilePointer(infoPtr->handle, 0, NULL, FILE_END);
    }

    if (WriteFile(infoPtr->handle, (LPVOID) buf, (DWORD) toWrite, &bytesWritten,
            (LPOVERLAPPED) NULL) == FALSE) {
        TclWinConvertError(GetLastError());
        *errorCode = errno;
        return -1;
    }
    infoPtr->dirty = 1;
    return bytesWritten;
}

/*
 *----------------------------------------------------------------------
 *
 * FileWatchProc --
 *
 *	Called by the notifier to set up to watch for events on this
 *	channel.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

static void
FileWatchProc(instanceData, mask)
    ClientData instanceData;		/* File state. */
    int mask;				/* What events to watch for; OR-ed
                                         * combination of TCL_READABLE,
                                         * TCL_WRITABLE and TCL_EXCEPTION. */
{
    FileInfo *infoPtr = (FileInfo *) instanceData;
    Tcl_Time blockTime = { 0, 0 };

    /*
     * Since the file is always ready for events, we set the block time
     * to zero so we will poll.
     */

    infoPtr->watchMask = mask & infoPtr->validMask;
    if (infoPtr->watchMask) {
	Tcl_SetMaxBlockTime(&blockTime);
    }
}

/*
 *----------------------------------------------------------------------
 *
 * FileGetHandleProc --
 *
 *	Called from Tcl_GetChannelHandle to retrieve OS handles from
 *	a file based channel.
 *
 * Results:
 *	Returns TCL_OK with the fd in handlePtr, or TCL_ERROR if
 *	there is no handle for the specified direction. 
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

static int
FileGetHandleProc(instanceData, direction, handlePtr)
    ClientData instanceData;	/* The file state. */
    int direction;		/* TCL_READABLE or TCL_WRITABLE */
    ClientData *handlePtr;	/* Where to store the handle.  */
{
    FileInfo *infoPtr = (FileInfo *) instanceData;

    if (direction & infoPtr->validMask) {
	*handlePtr = (ClientData) infoPtr->handle;
	return TCL_OK;
    } else {
	return TCL_ERROR;
    }
}


/*
 *----------------------------------------------------------------------
 *
 * TclpOpenFileChannel --
 *
 *	Open an File based channel on Unix systems.
 *
 * Results:
 *	The new channel or NULL. If NULL, the output argument
 *	errorCodePtr is set to a POSIX error.
 *
 * Side effects:
 *	May open the channel and may cause creation of a file on the
 *	file system.
 *
 *----------------------------------------------------------------------
 */

Tcl_Channel
TclpOpenFileChannel(interp, pathPtr, mode, permissions)
    Tcl_Interp *interp;			/* Interpreter for error reporting;
                                         * can be NULL. */
    Tcl_Obj *pathPtr;			/* Name of file to open. */
    int mode;				/* POSIX mode. */
    int permissions;			/* If the open involves creating a
                                         * file, with what modes to create
                                         * it? */
{
    Tcl_Channel channel = 0;
    int channelPermissions;
    DWORD accessMode, createMode, shareMode, flags, consoleParams, type;
    CONST TCHAR *nativeName;
    DCB dcb;
    HANDLE handle;
    char channelName[16 + TCL_INTEGER_SPACE];
    TclFile readFile = NULL;
    TclFile writeFile = NULL;

    nativeName = (TCHAR*) Tcl_FSGetNativePath(pathPtr);
    if (nativeName == NULL) {
	return NULL;
    }
    
    switch (mode & (O_RDONLY | O_WRONLY | O_RDWR)) {
	case O_RDONLY:
	    accessMode = GENERIC_READ;
	    channelPermissions = TCL_READABLE;
	    break;
	case O_WRONLY:
	    accessMode = GENERIC_WRITE;
	    channelPermissions = TCL_WRITABLE;
	    break;
	case O_RDWR:
	    accessMode = (GENERIC_READ | GENERIC_WRITE);
	    channelPermissions = (TCL_READABLE | TCL_WRITABLE);
	    break;
	default:
	    panic("TclpOpenFileChannel: invalid mode value");
	    break;
    }

    /*
     * Map the creation flags to the NT create mode.
     */

    switch (mode & (O_CREAT | O_EXCL | O_TRUNC)) {
	case (O_CREAT | O_EXCL):
	case (O_CREAT | O_EXCL | O_TRUNC):
	    createMode = CREATE_NEW;
	    break;
	case (O_CREAT | O_TRUNC):
	    createMode = CREATE_ALWAYS;
	    break;
	case O_CREAT:
	    createMode = OPEN_ALWAYS;
	    break;
	case O_TRUNC:
	case (O_TRUNC | O_EXCL):
	    createMode = TRUNCATE_EXISTING;
	    break;
	default:
	    createMode = OPEN_EXISTING;
	    break;
    }

    /*
     * If the file is being created, get the file attributes from the
     * permissions argument, else use the existing file attributes.
     */

    if (mode & O_CREAT) {
        if (permissions & S_IWRITE) {
            flags = FILE_ATTRIBUTE_NORMAL;
        } else {
            flags = FILE_ATTRIBUTE_READONLY;
        }
    } else {
	flags = (*tclWinProcs->getFileAttributesProc)(nativeName);
        if (flags == 0xFFFFFFFF) {
	    flags = 0;
	}
    }

    /*
     * Set up the file sharing mode.  We want to allow simultaneous access.
     */

    shareMode = FILE_SHARE_READ | FILE_SHARE_WRITE;

    /*
     * Now we get to create the file.
     */

    handle = (*tclWinProcs->createFileProc)(nativeName, accessMode, 
	    shareMode, NULL, createMode, flags, (HANDLE) NULL);

    if (handle == INVALID_HANDLE_VALUE) {
	DWORD err;
	err = GetLastError();
	if ((err & 0xffffL) == ERROR_OPEN_FAILED) {
	    err = (mode & O_CREAT) ? ERROR_FILE_EXISTS : ERROR_FILE_NOT_FOUND;
	}
        TclWinConvertError(err);
	if (interp != (Tcl_Interp *) NULL) {
            Tcl_AppendResult(interp, "couldn't open \"", 
			     Tcl_GetString(pathPtr), "\": ",
			     Tcl_PosixError(interp), (char *) NULL);
        }
        return NULL;
    }
    
    type = GetFileType(handle);

    /*
     * If the file is a character device, we need to try to figure out
     * whether it is a serial port, a console, or something else.  We
     * test for the console case first because this is more common.
     */

    if (type == FILE_TYPE_CHAR) {
	if (GetConsoleMode(handle, &consoleParams)) {
	    type = FILE_TYPE_CONSOLE;
	} else {
	    dcb.DCBlength = sizeof( DCB ) ;
	    if (GetCommState(handle, &dcb)) {
		type = FILE_TYPE_SERIAL;
	    }
		    
	}
    }