tclmacchan.c

tcl是工具命令语言

    chan = Tcl_CreateChannel(&fileChannelType, channelName, 
	(ClientData) fileState, channelPermissions);
    if (chan == (Tcl_Channel) NULL) {
	*errorCodePtr = errno = EFAULT;
	Tcl_SetErrno(errno);
	FSClose(fileRef);
	ckfree((char *) fileState);
        return NULL;
    }

    fileState->fileChan = chan;
    fileState->nextPtr = tsdPtr->firstFilePtr;
    tsdPtr->firstFilePtr = fileState;
    fileState->volumeRef = fileSpec.vRefNum;
    fileState->fileRef = fileRef;
    fileState->pending = 0;
    fileState->watchMask = 0;
    if (mode & O_APPEND) {
	fileState->appendMode = true;
    } else {
	fileState->appendMode = false;
    }
        
    if ((mode & O_APPEND) || (mode & O_APPEND)) {
        if (Tcl_Seek(chan, 0, SEEK_END) < 0) {
	    *errorCodePtr = errno = EFAULT;
	    Tcl_SetErrno(errno);
            Tcl_Close(NULL, chan);
            FSClose(fileRef);
            ckfree((char *) fileState);
            return NULL;
        }
    }
    
    return chan;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_MakeFileChannel --
 *
 *	Makes a Tcl_Channel from an existing OS level file handle.
 *
 * Results:
 *	The Tcl_Channel created around the preexisting OS level file handle.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

Tcl_Channel
Tcl_MakeFileChannel(handle, mode)
    ClientData handle;		/* OS level handle. */
    int mode;			/* ORed combination of TCL_READABLE and
                                 * TCL_WRITABLE to indicate file mode. */
{
    /*
     * Not implemented yet.
     */

    return NULL;
}

/*
 *----------------------------------------------------------------------
 *
 * FileBlockMode --
 *
 *	Set blocking or non-blocking mode on channel.  Macintosh files
 *	can never really be set to blocking or non-blocking modes.
 *	However, we don't generate an error - we just return success.
 *
 * Results:
 *	0 if successful, errno when failed.
 *
 * Side effects:
 *	Sets the device into blocking or non-blocking mode.
 *
 *----------------------------------------------------------------------
 */

static int
FileBlockMode(
    ClientData instanceData,		/* Unused. */
    int mode)				/* The mode to set. */
{
    return 0;
}

/*
 *----------------------------------------------------------------------
 *
 * FileClose --
 *
 *	Closes the IO channel.
 *
 * Results:
 *	0 if successful, the value of errno if failed.
 *
 * Side effects:
 *	Closes the physical channel
 *
 *----------------------------------------------------------------------
 */

static int
FileClose(
    ClientData instanceData,	/* Unused. */
    Tcl_Interp *interp)		/* Unused. */
{
    FileState *fileState = (FileState *) instanceData;
    int errorCode = 0;
    OSErr err;

    err = FSClose(fileState->fileRef);
    FlushVol(NULL, fileState->volumeRef);
    if (err != noErr) {
	errorCode = errno = TclMacOSErrorToPosixError(err);
	panic("error during file close");
    }

    ckfree((char *) fileState);
    Tcl_SetErrno(errorCode);
    return errorCode;
}

/*
 *----------------------------------------------------------------------
 *
 * FileInput --
 *
 *	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.
 *
 *----------------------------------------------------------------------
 */

int
FileInput(
    ClientData instanceData,	/* Unused. */
    char *buffer,				/* Where to store data read. */
    int bufSize,				/* How much space is available
                                 * in the buffer? */
    int *errorCodePtr)			/* Where to store error code. */
{
    FileState *fileState = (FileState *) instanceData;
    OSErr err;
    long length = bufSize;

    *errorCodePtr = 0;
    errno = 0;
    err = FSRead(fileState->fileRef, &length, buffer);
    if ((err == noErr) || (err == eofErr)) {
	return length;
    } else {
	switch (err) {
	    case ioErr:
		*errorCodePtr = errno = EIO;
	    case afpAccessDenied:
		*errorCodePtr = errno = EACCES;
	    default:
		*errorCodePtr = errno = EINVAL;
	}
        return -1;	
    }
    *errorCodePtr = errno;
    return -1;
}

/*
 *----------------------------------------------------------------------
 *
 * FileOutput--
 *
 *	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
FileOutput(
    ClientData instanceData,		/* Unused. */
    CONST char *buffer,			/* The data buffer. */
    int toWrite,			/* How many bytes to write? */
    int *errorCodePtr)			/* Where to store error code. */
{
    FileState *fileState = (FileState *) instanceData;
    long length = toWrite;
    OSErr err;

    *errorCodePtr = 0;
    errno = 0;
    
    if (fileState->appendMode == true) {
	FileSeek(instanceData, 0, SEEK_END, errorCodePtr);
	*errorCodePtr = 0;
    }
    
    err = FSWrite(fileState->fileRef, &length, buffer);
    if (err == noErr) {
	err = FlushFile(fileState->fileRef);
    } else {
	*errorCodePtr = errno = TclMacOSErrorToPosixError(err);
	return -1;
    }
    return length;
}

/*
 *----------------------------------------------------------------------
 *
 * FileSeek --
 *
 *	Seeks on an IO 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 int
FileSeek(
    ClientData instanceData,	/* Unused. */
    long offset,		/* Offset to seek to. */
    int mode,			/* Relative to where should we seek? */
    int *errorCodePtr)		/* To store error code. */
{
    FileState *fileState = (FileState *) instanceData;
    IOParam pb;
    OSErr err;

    *errorCodePtr = 0;
    pb.ioCompletion = NULL;
    pb.ioRefNum = fileState->fileRef;
    if (mode == SEEK_SET) {
	pb.ioPosMode = fsFromStart;
    } else if (mode == SEEK_END) {
	pb.ioPosMode = fsFromLEOF;
    } else if (mode == SEEK_CUR) {
	err = PBGetFPosSync((ParmBlkPtr) &pb);
	if (pb.ioResult == noErr) {
	    if (offset == 0) {
		return pb.ioPosOffset;
	    }
	    offset += pb.ioPosOffset;
	}
	pb.ioPosMode = fsFromStart;
    }
    pb.ioPosOffset = offset;
    err = PBSetFPosSync((ParmBlkPtr) &pb);
    if (pb.ioResult == noErr){
	return pb.ioPosOffset;
    } else if (pb.ioResult == eofErr) {
	long currentEOF, newEOF;
	long buffer, i, length;
	
	err = PBGetEOFSync((ParmBlkPtr) &pb);
	currentEOF = (long) pb.ioMisc;
	if (mode == SEEK_SET) {
	    newEOF = offset;
	} else if (mode == SEEK_END) {
	    newEOF = offset + currentEOF;
	} else if (mode == SEEK_CUR) {
	    err = PBGetFPosSync((ParmBlkPtr) &pb);
	    newEOF = offset + pb.ioPosOffset;
	}
	
	/*
	 * Write 0's to the new EOF.
	 */
	pb.ioPosOffset = 0;
	pb.ioPosMode = fsFromLEOF;
	err = PBGetFPosSync((ParmBlkPtr) &pb);
	length = 1;
	buffer = 0;
	for (i = 0; i < (newEOF - currentEOF); i++) {
	    err = FSWrite(fileState->fileRef, &length, &buffer);
	}
	err = PBGetFPosSync((ParmBlkPtr) &pb);
	if (pb.ioResult == noErr){
	    return pb.ioPosOffset;
	}
    }
    *errorCodePtr = errno = TclMacOSErrorToPosixError(err);
    return -1;
}

/*
 *----------------------------------------------------------------------
 *
 * CommonWatch --
 *
 *	Initialize the notifier to watch handles from this channel.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

static void
CommonWatch(
    ClientData instanceData,		/* The file state. */
    int mask)				/* Events of interest; an OR-ed
                                         * combination of TCL_READABLE,
                                         * TCL_WRITABLE and TCL_EXCEPTION. */
{
    FileState *infoPtr = (FileState *) instanceData;
    Tcl_Time blockTime = { 0, 0 };

    infoPtr->watchMask = mask;
    if (infoPtr->watchMask) {
	Tcl_SetMaxBlockTime(&blockTime);
    }
}

/*
 *----------------------------------------------------------------------
 *
 * TclpCutFileChannel --
 *
 *	Remove any thread local refs to this channel. See
 *	Tcl_CutChannel for more info.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Changes thread local list of valid channels.
 *
 *----------------------------------------------------------------------
 */

void
TclpCutFileChannel(chan)
    Tcl_Channel chan;			/* The channel being removed. Must
                                         * not be referenced in any
                                         * interpreter. */
{
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
    Channel *chanPtr = (Channel *) chan;
    FileState *infoPtr;
    FileState **nextPtrPtr;
    int removed = 0;

    if (chanPtr->typePtr != &fileChannelType)
        return;

    infoPtr = (FileState *) chanPtr->instanceData;

    for (nextPtrPtr = &(tsdPtr->firstFilePtr); (*nextPtrPtr) != NULL;
	 nextPtrPtr = &((*nextPtrPtr)->nextPtr)) {
	if ((*nextPtrPtr) == infoPtr) {
	    (*nextPtrPtr) = infoPtr->nextPtr;
	    removed = 1;
	    break;
	}
    }

    /*
     * This could happen if the channel was created in one thread
     * and then moved to another without updating the thread
     * local data in each thread.
     */

    if (!removed)
        panic("file info ptr not on thread channel list");

}

/*
 *----------------------------------------------------------------------
 *
 * TclpSpliceFileChannel --
 *
 *	Insert thread local ref for this channel.
 *	Tcl_SpliceChannel for more info.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Changes thread local list of valid channels.
 *
 *----------------------------------------------------------------------
 */

void
TclpSpliceFileChannel(chan)
    Tcl_Channel chan;			/* The channel being removed. Must
                                         * not be referenced in any
                                         * interpreter. */
{
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
    Channel *chanPtr = (Channel *) chan;
    FileState *infoPtr;

    if (chanPtr->typePtr != &fileChannelType)
        return;

    infoPtr = (FileState *) chanPtr->instanceData;

    infoPtr->nextPtr = tsdPtr->firstFilePtr;
    tsdPtr->firstFilePtr = infoPtr;
}