parser.c.svn-base

这是一个用于解析xml文件的类库。使用这个类库

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(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->inputNr == 1) return(0); /* End of main Input */
    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;

    /*
     * 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;
	    }
	    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;
	    }
	    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)) {
        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;
    int val = 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;
	    }
	    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;
	    }
	    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)) {
        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
 * 
 * [69] PEReference ::= '%' Name ';'
 *
 * [ WFC: No Recursion ]
 * A parsed entity must not contain a recursive
 * reference to itself, either directly or indirectly. 
 *
 * [ WFC: Entity Declared ]
 * In a document without any DTD, a document with only an internal DTD
 * subset which contains no parameter entity references, or a document
 * with "standalone='yes'", ...  ... The declaration of a parameter
 * entity must precede any reference to it...
 *
 * [ VC: Entity Declared ]
 * In a document with an external subset or external parameter entities
 * with "standalone='no'", ...  ... The declaration of a parameter entity
 * must precede any reference to it...
 *
 * [ WFC: In DTD ]
 * Parameter-entity references may only appear in the DTD.
 * NOTE: misleading but this is handled.
 *
 * A PEReference may have been detected in the current input stream
 * the handling is done accordingly to 
 *      http://www.w3.org/TR/REC-xml#entproc
 * i.e. 
 *   - Included in literal in entity values
 *   - Included as Parameter Entity reference within DTDs
 */
void
xmlParserHandlePEReference(xmlParserCtxtPtr ctxt) {
    const xmlChar *name;
    xmlEntityPtr entity = NULL;
    xmlParserInputPtr input;

    if (RAW != '%') return;
    switch(ctxt->instate) {
	case XML_PARSER_CDATA_SECTION:
	    return;
        case XML_PARSER_COMMENT:
	    return;
	case XML_PARSER_START_TAG:
	    return;
	case XML_PARSER_END_TAG:
	    return;
        case XML_PARSER_EOF:
	    xmlFatalErr(ctxt, XML_ERR_PEREF_AT_EOF, NULL);
	    return;
        case XML_PARSER_PROLOG:
	case XML_PARSER_START:
	case XML_PARSER_MISC:
	    xmlFatalErr(ctxt, XML_ERR_PEREF_IN_PROLOG, NULL);
	    return;
	case XML_PARSER_ENTITY_DECL:
        case XML_PARSER_CONTENT:
        case XML_PARSER_ATTRIBUTE_VALUE:
        case XML_PARSER_PI:
	case XML_PARSER_SYSTEM_LITERAL:
	case XML_PARSER_PUBLIC_LITERAL:
	    /* we just ignore it there */
	    return;
        case XML_PARSER_EPILOG:
	    xmlFatalErr(ctxt, XML_ERR_PEREF_IN_EPILOG, NULL);
	    return;
	case XML_PARSER_ENTITY_VALUE:
	    /*
	     * NOTE: in the case of entity values, we don't do the
	     *       substitution here since we need the literal
	     *       entity value to be able to save the internal
	     *       subset of the document.
	     *       This will be handled by xmlStringDecodeEntities
	     */
	    return;
        case XML_PARSER_DTD:
	    /*
	     * [WFC: Well-Formedness Constraint: PEs in Internal Subset]
	     * In the internal DTD subset, parameter-entity references
	     * can occur only where markup declarations can occur, not
	     * within markup declarations.
	     * In that case this is handled in xmlParseMarkupDecl
	     */
	    if ((ctxt->external == 0) && (ctxt->inputNr == 1))
		return;
	    if (IS_BLANK_CH(NXT(1)) || NXT(1) == 0)
		return;
            break;
        case XML_PARSER_IGNORE:
            return;
    }

    NEXT;
    name = xmlParseName(ctxt);
    if (xmlParserDebugEntities)
	xmlGenericError(xmlGenericErrorContext,
		"PEReference: %s\n", name);
    if (name == NULL) {
	xmlFatalErr(ctxt, XML_ERR_PEREF_NO_NAME, NULL);
    } else {
	if (RAW == ';') {
	    NEXT;
	    if ((ctxt->sax != NULL) && (ctxt->sax->getParameterEntity != NULL))
		entity = ctxt->sax->getParameterEntity(ctxt->userData, name);
	    if (entity == NULL) {
	        
		/*
		 * [ WFC: Entity Declared ]
		 * In a document without any DTD, a document with only an
		 * internal DTD subset which contains no parameter entity
		 * references, or a document with "standalone='yes'", ...
		 * ... The declaration of a parameter entity must precede
		 * any reference to it...
		 */