Tcl Source Code

    int inAllocated, outAllocated;
				/* Sizes of working buffers. */
    GzipHeader inHeader;	/* Header read from input stream, when
				 * decompressing a gzip stream. */
    GzipHeader outHeader;	/* Header to write to an output stream, when
				 * compressing a gzip stream. */
    Tcl_TimerToken timer;	/* Timer used for keeping events fresh. */
    Tcl_Obj *compDictObj;	/* Byte-array object containing compression
				 * dictionary (not dictObj!) to use if
				 * necessary. */
} ZlibChannelData;

/*
 * Value bits for the flags field. Definitions are:
 *	ASYNC -		Whether this is an asynchronous channel.
 *	IN_HEADER -	Whether the inHeader field has been registered with
 *			the input compressor.

static void		ConvertError(Tcl_Interp *interp, int code);
static void		ExtractHeader(gz_header *headerPtr, Tcl_Obj *dictObj);
static int		GenerateHeader(Tcl_Interp *interp, Tcl_Obj *dictObj,
			    GzipHeader *headerPtr, int *extraSizePtr);
static Tcl_Channel	ZlibStackChannelTransform(Tcl_Interp *interp,
			    int mode, int format, int level,
			    Tcl_Channel channel, Tcl_Obj *gzipHeaderDictPtr,
			    Tcl_Obj *compDictObj);
static void		ZlibStreamCleanup(ZlibStreamHandle *zshPtr);
static void		ZlibTransformTimerKill(ZlibChannelData *cd);
static void		ZlibTransformTimerRun(ClientData clientData);
static void		ZlibTransformTimerSetup(ZlibChannelData *cd);

/*
 * Type of zlib-based compressing and decompressing channels.

		Tcl_NewStringObj(headerPtr->text ? "text" : "binary", -1));
    }

    if (latin1enc != NULL) {
	Tcl_FreeEncoding(latin1enc);
    }
}

static int
SetInflateDictionary(
    z_streamp strm,
    Tcl_Obj *compDictObj)
{
    if (compDictObj != NULL) {
	int length;
	unsigned char *bytes = Tcl_GetByteArrayFromObj(compDictObj, &length);

	return inflateSetDictionary(strm, bytes, (unsigned) length);
    }
    return Z_OK;
}

static int
SetDeflateDictionary(
    z_streamp strm,
    Tcl_Obj *compDictObj)
{
    if (compDictObj != NULL) {
	int length;
	unsigned char *bytes = Tcl_GetByteArrayFromObj(compDictObj, &length);

	return deflateSetDictionary(strm, bytes, (unsigned) length);
    }
    return Z_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_ZlibStreamInit --
 *
 *	This command initializes a (de)compression context/handle for

	e = deflateInit2(&zshPtr->stream, level, Z_DEFLATED, wbits,
		MAX_MEM_LEVEL, Z_DEFAULT_STRATEGY);
	if (e == Z_OK && zshPtr->gzHeaderPtr) {
	    e = deflateSetHeader(&zshPtr->stream,
		    &zshPtr->gzHeaderPtr->header);
	}
	if (e == Z_OK && zshPtr->compDictObj) {




	    e = SetDeflateDictionary(&zshPtr->stream, zshPtr->compDictObj);

	}
    } else {
	e = inflateInit2(&zshPtr->stream, wbits);
	if (e == Z_OK && zshPtr->gzHeaderPtr) {
	    e = inflateGetHeader(&zshPtr->stream,
		    &zshPtr->gzHeaderPtr->header);
	}
	if (format==TCL_ZLIB_FORMAT_RAW && zshPtr->compDictObj && e==Z_OK) {
	    e = SetInflateDictionary(&zshPtr->stream, zshPtr->compDictObj);
	}
    }

    if (e != Z_OK) {
	ConvertError(interp, e);
	goto error;
    }

     * No output buffer available yet.
     */

    if (zshPtr->mode == TCL_ZLIB_STREAM_DEFLATE) {
	e = deflateInit2(&zshPtr->stream, zshPtr->level, Z_DEFLATED,
		zshPtr->wbits, MAX_MEM_LEVEL, Z_DEFAULT_STRATEGY);
	if (e == Z_OK && zshPtr->compDictObj) {




	    e = SetDeflateDictionary(&zshPtr->stream, zshPtr->compDictObj);

	}
    } else {
	e = inflateInit2(&zshPtr->stream, zshPtr->wbits);
	if (zshPtr->format == TCL_ZLIB_FORMAT_RAW && zshPtr->compDictObj
		&& e == Z_OK) {
	    e = SetInflateDictionary(&zshPtr->stream, zshPtr->compDictObj);
	}
    }

    if (e != Z_OK) {
	ConvertError(zshPtr->interp, e);
	/* TODO:cleanup */
	return TCL_ERROR;
    }

		 * And remove it from the list
		 */

		Tcl_ListObjReplace(NULL, zshPtr->inData, 0, 1, 0, NULL);
	    }
	}


	e = inflate(&zshPtr->stream, zshPtr->flush);
	if (e == Z_NEED_DICT && zshPtr->compDictObj) {




	    e = SetInflateDictionary(&zshPtr->stream, zshPtr->compDictObj);
	    if (e == Z_OK) {
		e = inflate(&zshPtr->stream, zshPtr->flush);



	    }
	};

	Tcl_ListObjLength(NULL, zshPtr->inData, &listLen);

	while ((zshPtr->stream.avail_out > 0)
		&& (e == Z_OK || e == Z_BUF_ERROR) && (listLen > 0)) {
	    /*
	     * State: We have not satisfied the request yet and there may be
	     * more to inflate.

	    Tcl_ListObjReplace(NULL, zshPtr->inData, 0, 1, 0, NULL);
	    listLen--;

	    /*
	     * And call inflate again.
	     */


	    e = inflate(&zshPtr->stream, zshPtr->flush);
	    if (e == Z_NEED_DICT && zshPtr->compDictObj) {




		e = SetInflateDictionary(&zshPtr->stream,zshPtr->compDictObj);

		if (e == Z_OK) {
		    e = inflate(&zshPtr->stream, zshPtr->flush);




		}
	    }
	}
	if (zshPtr->stream.avail_out > 0) {
	    Tcl_SetByteArrayLength(data,
		    existing + count - zshPtr->stream.avail_out);
	}

		    limit = 1;
		}
		break;
	    }
	}

	if (ZlibStackChannelTransform(interp, mode, format, level, chan,
		headerObj, NULL) == NULL) {
	    return TCL_ERROR;
	}
	Tcl_SetObjResult(interp, objv[3]);
	return TCL_OK;
    }
    };

	    }
	    if (cd->outStream.avail_out != (unsigned) cd->outAllocated) {
		if (Tcl_WriteRaw(cd->parent, cd->outBuffer,
			cd->outAllocated - cd->outStream.avail_out) < 0) {
		    /* TODO: is this the right way to do errors on close?
		     * Note: when close is called from FinalizeIOSubsystem
		     * then interp may be NULL */
		    if (!TclInThreadExit() && interp) {

			Tcl_AppendResult(interp,
				"error while finalizing file: ",
				Tcl_PosixError(interp), NULL);

		    }
		    result = TCL_ERROR;
		    break;
		}
	    }
	} while (e != Z_STREAM_END);
	e = deflateEnd(&cd->outStream);

    cd->inStream.next_out = (Bytef *) buf;
    cd->inStream.avail_out = toRead;
    if (cd->inStream.next_in == NULL) {
	goto doReadFirst;
    }
    while (1) {
	e = inflate(&cd->inStream, flush);
	if (e == Z_NEED_DICT && cd->compDictObj) {
	    e = SetInflateDictionary(&cd->inStream, cd->compDictObj);
	    if (e == Z_OK) {
		continue;
	    }
	}
	if ((e == Z_STREAM_END) || (e==Z_OK && cd->inStream.avail_out==0)) {
	    return toRead - cd->inStream.avail_out;
	}

	/*
	 * Z_BUF_ERROR can be ignored as per http://www.zlib.net/zlib_how.html
	 *

    Tcl_Interp *interp,
    const char *optionName,
    const char *value)
{
    ZlibChannelData *cd = instanceData;
    Tcl_DriverSetOptionProc *setOptionProc =
	    Tcl_ChannelSetOptionProc(Tcl_GetChannelType(cd->parent));
    static const char *chanOptions = "dictionary flush";
    int haveFlushOpt = (cd->mode == TCL_ZLIB_STREAM_DEFLATE);

    if (optionName && strcmp(optionName, "-dictionary") == 0) {
	// TODO dictionary option
    }

    if (haveFlushOpt && optionName && strcmp(optionName, "-flush") == 0) {
	int flushType;

	if (value[0] == 'f' && strcmp(value, "full") == 0) {
	    flushType = Z_FULL_FLUSH;
	} else if (value[0] == 's' && strcmp(value, "sync") == 0) {

    Tcl_Interp *interp,
    const char *optionName,
    Tcl_DString *dsPtr)
{
    ZlibChannelData *cd = instanceData;
    Tcl_DriverGetOptionProc *getOptionProc =
	    Tcl_ChannelGetOptionProc(Tcl_GetChannelType(cd->parent));
    static const char *chanOptions = "checksum dictionary header";

    /*
     * The "crc" option reports the current CRC (calculated with the Adler32
     * or CRC32 algorithm according to the format) given the data that has
     * been processed so far.
     */

	    Tcl_DStringAppendElement(dsPtr, "-checksum");
	    Tcl_DStringAppendElement(dsPtr, buf);
	} else {
	    Tcl_DStringAppend(dsPtr, buf, -1);
	    return TCL_OK;
	}
    }

    if (optionName == NULL || strcmp(optionName, "-dictionary") == 0) {
	// TODO dictionary option
    }

    /*
     * The "header" option, which is only valid on inflating gzip channels,
     * reports the header that has been read from the start of the stream.
     */

    if ((cd->flags & IN_HEADER) && ((optionName == NULL) ||

    int format,			/* One of the TCL_ZLIB_FORMAT_* values that
				 * indicates what compressed format to allow.
				 * TCL_ZLIB_FORMAT_AUTO is only supported for
				 * decompressing transforms. */
    int level,			/* What compression level to use. Ignored for
				 * decompressing transforms. */
    Tcl_Channel channel,	/* The channel to attach to. */
    Tcl_Obj *gzipHeaderDictPtr,	/* A description of header to use, or NULL to
				 * use a default. Ignored if not compressing
				 * to produce gzip-format data. */
    Tcl_Obj *compDictObj)	/* Byte-array object containing compression
				 * dictionary (not dictObj!) to use if
				 * necessary. */
{
    ZlibChannelData *cd = ckalloc(sizeof(ZlibChannelData));
    Tcl_Channel chan;
    int wbits = 0;
    int e;

    if (mode != TCL_ZLIB_STREAM_DEFLATE && mode != TCL_ZLIB_STREAM_INFLATE) {

		    &cd->inHeader.nativeFilenameBuf;
	    cd->inHeader.header.name_max = MAXPATHLEN - 1;
	    cd->inHeader.header.comment = (Bytef *)
		    &cd->inHeader.nativeCommentBuf;
	    cd->inHeader.header.comm_max = MAX_COMMENT_LEN - 1;
	}
    }

    if (compDictObj != NULL) {
	cd->compDictObj = Tcl_DuplicateObj(compDictObj);
	Tcl_IncrRefCount(cd->compDictObj);
	Tcl_GetByteArrayFromObj(cd->compDictObj, NULL);
    }

    if (format == TCL_ZLIB_FORMAT_RAW) {
	wbits = WBITS_RAW;
    } else if (format == TCL_ZLIB_FORMAT_ZLIB) {
	wbits = WBITS_ZLIB;
    } else if (format == TCL_ZLIB_FORMAT_GZIP) {
	wbits = WBITS_GZIP;

	cd->outBuffer = ckalloc(cd->outAllocated);
	if (cd->flags & OUT_HEADER) {
	    e = deflateSetHeader(&cd->outStream, &cd->outHeader.header);
	    if (e != Z_OK) {
		goto error;
	    }
	}
	if (cd->compDictObj) {
	    e = SetDeflateDictionary(&cd->outStream, cd->compDictObj);
	    if (e != Z_OK) {
		goto error;
	    }
	}
    }

    chan = Tcl_StackChannel(interp, &zlibChannelType, cd,
	    Tcl_GetChannelMode(channel), channel);
    if (chan == NULL) {
	goto error;
    }

	ckfree(cd->inBuffer);
	inflateEnd(&cd->inStream);
    }
    if (cd->outBuffer) {
	ckfree(cd->outBuffer);
	deflateEnd(&cd->outStream);
    }
    if (cd->compDictObj) {
	Tcl_DecrRefCount(cd->compDictObj);
    }
    ckfree(cd);
    return NULL;
}

/*
 *----------------------------------------------------------------------
 *	Finally, the TclZlibInit function. Used to install the zlib API.