parser.c

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	    xmlPopInput(ctxt);						\
  } while (0)

#define SKIPL(val) do {							\
    int skipl;								\
    for(skipl=0; skipl<val; skipl++) {					\
    	if (*(ctxt->input->cur) == '\n') {				\
	ctxt->input->line++; ctxt->input->col = 1;			\
    	} else ctxt->input->col++;					\
    	ctxt->nbChars++;						\
	ctxt->input->cur++;						\
    }									\
    if (*ctxt->input->cur == '%') xmlParserHandlePEReference(ctxt);	\
    if ((*ctxt->input->cur == 0) &&					\
        (xmlParserInputGrow(ctxt->input, INPUT_CHUNK) <= 0))		\
	    xmlPopInput(ctxt);						\
  } while (0)

#define SHRINK if ((ctxt->progressive == 0) &&				\
		   (ctxt->input->cur - ctxt->input->base > 2 * INPUT_CHUNK) && \
		   (ctxt->input->end - ctxt->input->cur < 2 * INPUT_CHUNK)) \
	xmlSHRINK (ctxt);

static void xmlSHRINK (xmlParserCtxtPtr ctxt) {
    xmlParserInputShrink(ctxt->input);
    if ((*ctxt->input->cur == 0) &&
        (xmlParserInputGrow(ctxt->input, INPUT_CHUNK) <= 0))
	    xmlPopInput(ctxt);
  }

#define GROW if ((ctxt->progressive == 0) &&				\
		 (ctxt->input->end - ctxt->input->cur < INPUT_CHUNK))	\
	xmlGROW (ctxt);

static void xmlGROW (xmlParserCtxtPtr ctxt) {
    xmlParserInputGrow(ctxt->input, INPUT_CHUNK);
    if ((*ctxt->input->cur == 0) &&
        (xmlParserInputGrow(ctxt->input, INPUT_CHUNK) <= 0))
	    xmlPopInput(ctxt);
}

#define SKIP_BLANKS xmlSkipBlankChars(ctxt)

#define NEXT xmlNextChar(ctxt)

#define NEXT1 {								\
	ctxt->input->col++;						\
	ctxt->input->cur++;						\
	ctxt->nbChars++;						\
	if (*ctxt->input->cur == 0)					\
	    xmlParserInputGrow(ctxt->input, INPUT_CHUNK);		\
    }

#define NEXTL(l) do {							\
    if (*(ctxt->input->cur) == '\n') {					\
	ctxt->input->line++; ctxt->input->col = 1;			\
    } else ctxt->input->col++;						\
    ctxt->input->cur += l;				\
    if (*ctxt->input->cur == '%') xmlParserHandlePEReference(ctxt);	\
  } while (0)

#define CUR_CHAR(l) xmlCurrentChar(ctxt, &l)
#define CUR_SCHAR(s, l) xmlStringCurrentChar(ctxt, s, &l)

#define COPY_BUF(l,b,i,v)						\
    if (l == 1) b[i++] = (xmlChar) v;					\
    else i += xmlCopyCharMultiByte(&b[i],v)

/**
 * xmlSkipBlankChars:
 * @ctxt:  the XML parser context
 *
 * skip all blanks character found at that point in the input streams.
 * It pops up finished entities in the process if allowable at that point.
 *
 * Returns the number of space chars skipped
 */

int
xmlSkipBlankChars(xmlParserCtxtPtr ctxt) {
    int res = 0;

    /*
     * It's Okay to use CUR/NEXT here since all the blanks are on
     * the ASCII range.
     */
    if ((ctxt->inputNr == 1) && (ctxt->instate != XML_PARSER_DTD)) {
	const xmlChar *cur;
	/*
	 * if we are in the document content, go really fast
	 */
	cur = ctxt->input->cur;
	while (IS_BLANK_CH(*cur)) {
	    if (*cur == '\n') {
		ctxt->input->line++; ctxt->input->col = 1;
	    }
	    cur++;
	    res++;
	    if (*cur == 0) {
		ctxt->input->cur = cur;
		xmlParserInputGrow(ctxt->input, INPUT_CHUNK);
		cur = ctxt->input->cur;
	    }
	}
	ctxt->input->cur = cur;
    } else {
	int cur;
	do {
	    cur = CUR;
	    while (IS_BLANK_CH(cur)) { /* CHECKED tstblanks.xml */
		NEXT;
		cur = CUR;
		res++;
	    }
	    while ((cur == 0) && (ctxt->inputNr > 1) &&
		   (ctxt->instate != XML_PARSER_COMMENT)) {
		xmlPopInput(ctxt);
		cur = CUR;
	    }
	    /*
	     * Need to handle support of entities branching here
	     */
	    if (*ctxt->input->cur == '%') xmlParserHandlePEReference(ctxt);
	} while (IS_BLANK(cur)); /* CHECKED tstblanks.xml */
    }
    return(res);
}

/************************************************************************
 *									*
 *		Commodity functions to handle entities			*
 *									*
 ************************************************************************/

/**
 * xmlPopInput:
 * @ctxt:  an XML parser context
 *
 * xmlPopInput: the current input pointed by ctxt->input came to an end
 *          pop it and return the next char.
 *
 * Returns the current xmlChar in the parser context
 */
xmlChar
xmlPopInput(xmlParserCtxtPtr ctxt) {
    if ((ctxt == NULL) || (ctxt->inputNr <= 1)) return(0);
    if (xmlParserDebugEntities)
	xmlGenericError(xmlGenericErrorContext,
		"Popping input %d\n", ctxt->inputNr);
    xmlFreeInputStream(inputPop(ctxt));
    if ((*ctxt->input->cur == 0) &&
        (xmlParserInputGrow(ctxt->input, INPUT_CHUNK) <= 0))
	    return(xmlPopInput(ctxt));
    return(CUR);
}

/**
 * xmlPushInput:
 * @ctxt:  an XML parser context
 * @input:  an XML parser input fragment (entity, XML fragment ...).
 *
 * xmlPushInput: switch to a new input stream which is stacked on top
 *               of the previous one(s).
 */
void
xmlPushInput(xmlParserCtxtPtr ctxt, xmlParserInputPtr input) {
    if (input == NULL) return;

    if (xmlParserDebugEntities) {
	if ((ctxt->input != NULL) && (ctxt->input->filename))
	    xmlGenericError(xmlGenericErrorContext,
		    "%s(%d): ", ctxt->input->filename,
		    ctxt->input->line);
	xmlGenericError(xmlGenericErrorContext,
		"Pushing input %d : %.30s\n", ctxt->inputNr+1, input->cur);
    }
    inputPush(ctxt, input);
    GROW;
}

/**
 * xmlParseCharRef:
 * @ctxt:  an XML parser context
 *
 * parse Reference declarations
 *
 * [66] CharRef ::= '&#' [0-9]+ ';' |
 *                  '&#x' [0-9a-fA-F]+ ';'
 *
 * [ WFC: Legal Character ]
 * Characters referred to using character references must match the
 * production for Char. 
 *
 * Returns the value parsed (as an int), 0 in case of error
 */
int
xmlParseCharRef(xmlParserCtxtPtr ctxt) {
    unsigned int val = 0;
    int count = 0;
    unsigned int outofrange = 0;

    /*
     * Using RAW/CUR/NEXT is okay since we are working on ASCII range here
     */
    if ((RAW == '&') && (NXT(1) == '#') &&
        (NXT(2) == 'x')) {
	SKIP(3);
	GROW;
	while (RAW != ';') { /* loop blocked by count */
	    if (count++ > 20) {
		count = 0;
		GROW;
	    }
	    if ((RAW >= '0') && (RAW <= '9')) 
	        val = val * 16 + (CUR - '0');
	    else if ((RAW >= 'a') && (RAW <= 'f') && (count < 20))
	        val = val * 16 + (CUR - 'a') + 10;
	    else if ((RAW >= 'A') && (RAW <= 'F') && (count < 20))
	        val = val * 16 + (CUR - 'A') + 10;
	    else {
		xmlFatalErr(ctxt, XML_ERR_INVALID_HEX_CHARREF, NULL);
		val = 0;
		break;
	    }
	    if (val > 0x10FFFF)
	        outofrange = val;

	    NEXT;
	    count++;
	}
	if (RAW == ';') {
	    /* on purpose to avoid reentrancy problems with NEXT and SKIP */
	    ctxt->input->col++;
	    ctxt->nbChars ++;
	    ctxt->input->cur++;
	}
    } else if  ((RAW == '&') && (NXT(1) == '#')) {
	SKIP(2);
	GROW;
	while (RAW != ';') { /* loop blocked by count */
	    if (count++ > 20) {
		count = 0;
		GROW;
	    }
	    if ((RAW >= '0') && (RAW <= '9')) 
	        val = val * 10 + (CUR - '0');
	    else {
		xmlFatalErr(ctxt, XML_ERR_INVALID_DEC_CHARREF, NULL);
		val = 0;
		break;
	    }
	    if (val > 0x10FFFF)
	        outofrange = val;

	    NEXT;
	    count++;
	}
	if (RAW == ';') {
	    /* on purpose to avoid reentrancy problems with NEXT and SKIP */
	    ctxt->input->col++;
	    ctxt->nbChars ++;
	    ctxt->input->cur++;
	}
    } else {
        xmlFatalErr(ctxt, XML_ERR_INVALID_CHARREF, NULL);
    }

    /*
     * [ WFC: Legal Character ]
     * Characters referred to using character references must match the
     * production for Char. 
     */
    if ((IS_CHAR(val) && (outofrange == 0))) {
        return(val);
    } else {
        xmlFatalErrMsgInt(ctxt, XML_ERR_INVALID_CHAR,
                          "xmlParseCharRef: invalid xmlChar value %d\n",
	                  val);
    }
    return(0);
}

/**
 * xmlParseStringCharRef:
 * @ctxt:  an XML parser context
 * @str:  a pointer to an index in the string
 *
 * parse Reference declarations, variant parsing from a string rather
 * than an an input flow.
 *
 * [66] CharRef ::= '&#' [0-9]+ ';' |
 *                  '&#x' [0-9a-fA-F]+ ';'
 *
 * [ WFC: Legal Character ]
 * Characters referred to using character references must match the
 * production for Char. 
 *
 * Returns the value parsed (as an int), 0 in case of error, str will be
 *         updated to the current value of the index
 */
static int
xmlParseStringCharRef(xmlParserCtxtPtr ctxt, const xmlChar **str) {
    const xmlChar *ptr;
    xmlChar cur;
    unsigned int val = 0;
    unsigned int outofrange = 0;

    if ((str == NULL) || (*str == NULL)) return(0);
    ptr = *str;
    cur = *ptr;
    if ((cur == '&') && (ptr[1] == '#') && (ptr[2] == 'x')) {
	ptr += 3;
	cur = *ptr;
	while (cur != ';') { /* Non input consuming loop */
	    if ((cur >= '0') && (cur <= '9')) 
	        val = val * 16 + (cur - '0');
	    else if ((cur >= 'a') && (cur <= 'f'))
	        val = val * 16 + (cur - 'a') + 10;
	    else if ((cur >= 'A') && (cur <= 'F'))
	        val = val * 16 + (cur - 'A') + 10;
	    else {
		xmlFatalErr(ctxt, XML_ERR_INVALID_HEX_CHARREF, NULL);
		val = 0;
		break;
	    }
	    if (val > 0x10FFFF)
	        outofrange = val;

	    ptr++;
	    cur = *ptr;
	}
	if (cur == ';')
	    ptr++;
    } else if  ((cur == '&') && (ptr[1] == '#')){
	ptr += 2;
	cur = *ptr;
	while (cur != ';') { /* Non input consuming loops */
	    if ((cur >= '0') && (cur <= '9')) 
	        val = val * 10 + (cur - '0');
	    else {
		xmlFatalErr(ctxt, XML_ERR_INVALID_DEC_CHARREF, NULL);
		val = 0;
		break;
	    }
	    if (val > 0x10FFFF)
	        outofrange = val;

	    ptr++;
	    cur = *ptr;
	}
	if (cur == ';')
	    ptr++;
    } else {
	xmlFatalErr(ctxt, XML_ERR_INVALID_CHARREF, NULL);
	return(0);
    }
    *str = ptr;

    /*
     * [ WFC: Legal Character ]
     * Characters referred to using character references must match the
     * production for Char. 
     */
    if ((IS_CHAR(val) && (outofrange == 0))) {
        return(val);
    } else {
        xmlFatalErrMsgInt(ctxt, XML_ERR_INVALID_CHAR,
			  "xmlParseStringCharRef: invalid xmlChar value %d\n",
			  val);
    }
    return(0);
}

/**
 * xmlNewBlanksWrapperInputStream:
 * @ctxt:  an XML parser context
 * @entity:  an Entity pointer
 *
 * Create a new input stream for wrapping
 * blanks around a PEReference
 *
 * Returns the new input stream or NULL
 */
 
static void deallocblankswrapper (xmlChar *str) {xmlFree(str);}
 
static xmlParserInputPtr
xmlNewBlanksWrapperInputStream(xmlParserCtxtPtr ctxt, xmlEntityPtr entity) {
    xmlParserInputPtr input;
    xmlChar *buffer;
    size_t length;
    if (entity == NULL) {
	xmlFatalErr(ctxt, XML_ERR_INTERNAL_ERROR,
	            "xmlNewBlanksWrapperInputStream entity\n");
	return(NULL);
    }
    if (xmlParserDebugEntities)
	xmlGenericError(xmlGenericErrorContext,
		"new blanks wrapper for entity: %s\n", entity->name);
    input = xmlNewInputStream(ctxt);
    if (input == NULL) {
	return(NULL);
    }
    length = xmlStrlen(entity->name) + 5;
    buffer = xmlMallocAtomic(length);
    if (buffer == NULL) {
	xmlErrMemory(ctxt, NULL);
    	return(NULL);
    }
    buffer [0] = ' ';
    buffer [1] = '%';
    buffer [length-3] = ';';
    buffer [length-2] = ' ';
    buffer [length-1] = 0;
    memcpy(buffer + 2, entity->name, length - 5);
    input->free = deallocblankswrapper;
    input->base = buffer;
    input->cur = buffer;
    input->length = length;
    input->end = &buffer[length];
    return(input);
}

/**
 * xmlParserHandlePEReference:
 * @ctxt:  the parser context
 *