Tcl Source Code

    statePtr->chPtr		= NULL;
    statePtr->interestMask	= 0;
    statePtr->scriptRecordPtr	= NULL;
    statePtr->bufSize		= CHANNELBUFFER_DEFAULT_SIZE;
    statePtr->timer		= NULL;
    statePtr->csPtrR		= NULL;
    statePtr->csPtrW		= NULL;

    statePtr->outputStage	= NULL;
    if ((statePtr->encoding != NULL) && GotFlag(statePtr, TCL_WRITABLE)) {
	statePtr->outputStage = ckalloc(statePtr->bufSize + 2);
    }

    /*
     * As we are creating the channel, it is obviously the top for now.
     */

    statePtr->topChanPtr	= chanPtr;
    statePtr->bottomChanPtr	= chanPtr;

    if (chanPtr == statePtr->bottomChanPtr) {
	if (statePtr->channelName != NULL) {
	    ckfree(statePtr->channelName);
	    statePtr->channelName = NULL;
	}

	Tcl_FreeEncoding(statePtr->encoding);
	if (statePtr->outputStage != NULL) {
	    ckfree(statePtr->outputStage);
	    statePtr->outputStage = NULL;
	}
    }

    /*
     * If we are being called synchronously, report either any latent error on
     * the channel or the current error.
     */

WriteChars(
    Channel *chanPtr,		/* The channel to buffer output for. */
    const char *src,		/* UTF-8 string to write. */
    int srcLen)			/* Length of UTF-8 string in bytes. */
{
    ChannelState *statePtr = chanPtr->state;
				/* State info for channel */
    ChannelBuffer *bufPtr;
    char *dst, *stage;
    int saved, savedLF, sawLF, total, dstLen, stageMax, dstWrote;
    int stageLen, toWrite, stageRead, endEncoding, result;
    int consumedSomething, translate;
    Tcl_Encoding encoding;
    char safe[BUFFER_PADDING];

    if (srcLen) {
        WillWrite(chanPtr);
    }

    total = 0;
    sawLF = 0;
    savedLF = 0;
    saved = 0;
    encoding = statePtr->encoding;

    /*
     * Write the terminated escape sequence even if srcLen is 0.
     */

    endEncoding = ((statePtr->outputEncodingFlags & TCL_ENCODING_END) != 0);

    translate = GotFlag(statePtr, CHANNEL_LINEBUFFERED)
	    || (statePtr->outputTranslation != TCL_TRANSLATE_LF);

    /*
     * Loop over all UTF-8 characters in src, storing them in staging buffer
     * with proper EOL translation.
     */

    consumedSomething = 1;
    while (consumedSomething && (srcLen + savedLF + endEncoding > 0)) {
	consumedSomething = 0;

	if (translate) {
	    stage = statePtr->outputStage;
	    stageMax = statePtr->bufSize;
	    stageLen = stageMax;

	    toWrite = stageLen;
	    if (toWrite > srcLen) {
		toWrite = srcLen;
	    }

	    if (savedLF) {
		/*
		 * A '\n' was left over from last call to TranslateOutputEOL()
		 * and we need to store it in the staging buffer. If the
		 * channel is line-based, we will need to flush the output
		 * buffer (after translating the staging buffer).
		 */

		*stage++ = '\n';
		stageLen--;
		sawLF++;
	    }
	    if (TranslateOutputEOL(statePtr, stage, src, &stageLen,
		    &toWrite)) {
		sawLF++;
	    }

	    stage -= savedLF;
	    stageLen += savedLF;
	    savedLF = 0;

	    if (stageLen > stageMax) {
		savedLF = 1;
		stageLen = stageMax;
	    }
	} else {
	    stage = (char *) src;
	    stageLen = srcLen;
	    toWrite = stageLen;
	}
	src += toWrite;
	srcLen -= toWrite;

	/*
	 * Loop over all UTF-8 characters in staging buffer, converting them
	 * to external encoding, storing them in output buffer.
	 */

	while (stageLen + saved + endEncoding > 0) {
	    bufPtr = statePtr->curOutPtr;
	    if (bufPtr == NULL) {
		bufPtr = AllocChannelBuffer(statePtr->bufSize);
		statePtr->curOutPtr = bufPtr;
	    }
	    dst = InsertPoint(bufPtr);
	    dstLen = SpaceLeft(bufPtr);

	    if (saved != 0) {
		/*
		 * Here's some translated bytes left over from the last buffer
		 * that we need to stick at the beginning of this buffer.
		 */

		memcpy(dst, safe, (size_t) saved);
		bufPtr->nextAdded += saved;
		dst += saved;
		dstLen -= saved;
		saved = 0;
	    }



	    result = Tcl_UtfToExternal(NULL, encoding, stage, stageLen,
		    statePtr->outputEncodingFlags,
		    &statePtr->outputEncodingState, dst,
		    dstLen + BUFFER_PADDING, &stageRead, &dstWrote, NULL);

	    /*
	     * Fix for SF #506297, reported by Martin Forssen
	     * <[email protected]>.
	     *

	     * The encoding chosen in the script exposing the bug writes out
	     * three intro characters when TCL_ENCODING_START is set, but does
	     * not consume any input as TCL_ENCODING_END is cleared. As some
	     * output was generated the enclosing loop calls UtfToExternal
	     * again, again with START set. Three more characters in the out

	     * and still no use of input ... To break this infinite loop we

	     * remove TCL_ENCODING_START from the set of flags after the first
	     * call (no condition is required, the later calls remove an unset
	     * flag, which is a no-op). This causes the subsequent calls to





	     * UtfToExternal to consume and convert the actual input.




	     */



















	    statePtr->outputEncodingFlags &= ~TCL_ENCODING_START;



	    /*
	     * The following code must be executed only when result is not 0.
	     */



	    if ((result != 0) && (stageRead + dstWrote == 0)) {
		/*
		 * We have an incomplete UTF-8 character at the end of the
		 * staging buffer. It will get moved to the beginning of the
		 * staging buffer followed by more bytes from src.
		 */


		src -= stageLen;
		srcLen += stageLen;


		stageLen = 0;

		savedLF = 0;
		break;
	    }
	    bufPtr->nextAdded += dstWrote;
	    if (IsBufferOverflowing(bufPtr)) {
		/*
		 * When translating from UTF-8 to external encoding, we
		 * allowed the translation to produce a character that crossed
		 * the end of the output buffer, so that we would get a
		 * completely full buffer before flushing it. The extra bytes
		 * will be moved to the beginning of the next buffer.
		 */

		saved = -SpaceLeft(bufPtr);
		memcpy(safe, dst + dstLen, (size_t) saved);
		bufPtr->nextAdded = bufPtr->bufLength;
	    }
	    if (CheckFlush(chanPtr, bufPtr, sawLF) != 0) {
		return -1;
	    }

	    total += dstWrote;
	    stage += stageRead;
	    stageLen -= stageRead;
	    sawLF = 0;

	    consumedSomething = 1;

	    /*
	     * If all translated characters are written to the buffer,
	     * endEncoding is set to 0 because the escape sequence may be

	     * output.
	     */


	    if ((stageLen + saved == 0) && (result == 0)) {
		endEncoding = 0;
	    }
	}
    }






    /*
     * If nothing was written and it happened because there was no progress in
     * the UTF conversion, we throw an error.
     */

    if (!consumedSomething && (total == 0)) {
	Tcl_SetErrno(EINVAL);
	return -1;
    }
    return total;
}

/*
 *---------------------------------------------------------------------------
 *
 * TranslateOutputEOL --

	sz = 1;
    } else if (sz > MAX_CHANNEL_BUFFER_SIZE) {
	sz = MAX_CHANNEL_BUFFER_SIZE;
    }

    statePtr = ((Channel *) chan)->state;
    statePtr->bufSize = sz;

    if (statePtr->outputStage != NULL) {
	ckfree(statePtr->outputStage);
	statePtr->outputStage = NULL;
    }
    if ((statePtr->encoding != NULL) && GotFlag(statePtr, TCL_WRITABLE)) {
	statePtr->outputStage = ckalloc(statePtr->bufSize + 2);
    }
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_GetChannelBufferSize --
 *

	    && (statePtr->inQueueHead->nextPtr == NULL)
	    && IsBufferEmpty(statePtr->inQueueHead)) {
	RecycleBuffer(statePtr, statePtr->inQueueHead, 1);
	statePtr->inQueueHead = NULL;
	statePtr->inQueueTail = NULL;
    }

    /*
     * If encoding or bufsize changes, need to update output staging buffer.
     */

    if (statePtr->outputStage != NULL) {
	ckfree(statePtr->outputStage);
	statePtr->outputStage = NULL;
    }
    if ((statePtr->encoding != NULL) && GotFlag(statePtr, TCL_WRITABLE)) {
	statePtr->outputStage = ckalloc(statePtr->bufSize + 2);
    }
    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * CleanupChannelHandlers --