xpointer.c

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		if (list == NULL)
		    list = tmp;
		else {
		    if (last != NULL)
			xmlAddNextSibling(last, tmp);
		    else
			xmlAddChild(parent, tmp);
		}
		last = NULL;
		parent = tmp;

		if (index2 > 1) {
		    end = xmlXPtrGetNthChild(cur, index2 - 1);
		    index2 = 0;
		}
		if ((cur == start) && (index1 > 1)) {
		    cur = xmlXPtrGetNthChild(cur, index1 - 1);
		    index1 = 0;
		} else {
		    cur = cur->children;
		}
		/*
		 * Now gather the remaining nodes from cur to end
		 */
		continue; /* while */
	    }
	} else if ((cur == start) &&
		   (list == NULL) /* looks superfluous but ... */ ) {
	    if ((cur->type == XML_TEXT_NODE) ||
		(cur->type == XML_CDATA_SECTION_NODE)) {
		const xmlChar *content = cur->content;

		if (content == NULL) {
		    tmp = xmlNewTextLen(NULL, 0);
		} else {
		    if (index1 > 1) {
			content += (index1 - 1);
		    }
		    tmp = xmlNewText(content);
		}
		last = list = tmp;
	    } else {
		if ((cur == start) && (index1 > 1)) {
		    tmp = xmlCopyNode(cur, 0);
		    list = tmp;
		    parent = tmp;
		    last = NULL;
		    cur = xmlXPtrGetNthChild(cur, index1 - 1);
		    index1 = 0;
		    /*
		     * Now gather the remaining nodes from cur to end
		     */
		    continue; /* while */
		}
		tmp = xmlCopyNode(cur, 1);
		list = tmp;
		parent = NULL;
		last = tmp;
	    }
	} else {
	    tmp = NULL;
	    switch (cur->type) {
		case XML_DTD_NODE:
		case XML_ELEMENT_DECL:
		case XML_ATTRIBUTE_DECL:
		case XML_ENTITY_NODE:
		    /* Do not copy DTD informations */
		    break;
		case XML_ENTITY_DECL:
		    TODO /* handle crossing entities -> stack needed */
		    break;
		case XML_XINCLUDE_START:
		case XML_XINCLUDE_END:
		    /* don't consider it part of the tree content */
		    break;
		case XML_ATTRIBUTE_NODE:
		    /* Humm, should not happen ! */
		    STRANGE
		    break;
		default:
		    tmp = xmlCopyNode(cur, 1);
		    break;
	    }
	    if (tmp != NULL) {
		if ((list == NULL) || ((last == NULL) && (parent == NULL)))  {
		    STRANGE
		    return(NULL);
		}
		if (last != NULL)
		    xmlAddNextSibling(last, tmp);
		else {
		    xmlAddChild(parent, tmp);
		    last = tmp;
		}
	    }
	}
	/*
	 * Skip to next node in document order
	 */
	if ((list == NULL) || ((last == NULL) && (parent == NULL)))  {
	    STRANGE
	    return(NULL);
	}
	cur = xmlXPtrAdvanceNode(cur, NULL);
    }
    return(list);
}

/**
 * xmlXPtrBuildNodeList:
 * @obj:  the XPointer result from the evaluation.
 *
 * Build a node list tree copy of the XPointer result.
 * This will drop Attributes and Namespace declarations.
 *
 * Returns an xmlNodePtr list or NULL.
 *         the caller has to free the node tree.
 */
xmlNodePtr
xmlXPtrBuildNodeList(xmlXPathObjectPtr obj) {
    xmlNodePtr list = NULL, last = NULL;
    int i;

    if (obj == NULL)
	return(NULL);
    switch (obj->type) {
        case XPATH_NODESET: {
	    xmlNodeSetPtr set = obj->nodesetval;
	    if (set == NULL)
		return(NULL);
	    for (i = 0;i < set->nodeNr;i++) {
		if (set->nodeTab[i] == NULL)
		    continue;
		switch (set->nodeTab[i]->type) {
		    case XML_TEXT_NODE:
		    case XML_CDATA_SECTION_NODE:
		    case XML_ELEMENT_NODE:
		    case XML_ENTITY_REF_NODE:
		    case XML_ENTITY_NODE:
		    case XML_PI_NODE:
		    case XML_COMMENT_NODE:
		    case XML_DOCUMENT_NODE:
		    case XML_HTML_DOCUMENT_NODE:
#ifdef LIBXML_DOCB_ENABLED
		    case XML_DOCB_DOCUMENT_NODE:
#endif
		    case XML_XINCLUDE_START:
		    case XML_XINCLUDE_END:
			break;
		    case XML_ATTRIBUTE_NODE:
		    case XML_NAMESPACE_DECL:
		    case XML_DOCUMENT_TYPE_NODE:
		    case XML_DOCUMENT_FRAG_NODE:
		    case XML_NOTATION_NODE:
		    case XML_DTD_NODE:
		    case XML_ELEMENT_DECL:
		    case XML_ATTRIBUTE_DECL:
		    case XML_ENTITY_DECL:
			continue; /* for */
		}
		if (last == NULL)
		    list = last = xmlCopyNode(set->nodeTab[i], 1);
		else {
		    xmlAddNextSibling(last, xmlCopyNode(set->nodeTab[i], 1));
		    if (last->next != NULL)
			last = last->next;
		}
	    }
	    break;
	}
	case XPATH_LOCATIONSET: {
	    xmlLocationSetPtr set = (xmlLocationSetPtr) obj->user;
	    if (set == NULL)
		return(NULL);
	    for (i = 0;i < set->locNr;i++) {
		if (last == NULL)
		    list = last = xmlXPtrBuildNodeList(set->locTab[i]);
		else
		    xmlAddNextSibling(last,
			    xmlXPtrBuildNodeList(set->locTab[i]));
		if (last != NULL) {
		    while (last->next != NULL)
			last = last->next;
		}
	    }
	    break;
	}
	case XPATH_RANGE:
	    return(xmlXPtrBuildRangeNodeList(obj));
	case XPATH_POINT:
	    return(xmlCopyNode(obj->user, 0));
	default:
	    break;
    }
    return(list);
}

/************************************************************************
 *									*
 *			XPointer functions				*
 *									*
 ************************************************************************/

/**
 * xmlXPtrNbLocChildren:
 * @node:  an xmlNodePtr
 *
 * Count the number of location children of @node or the length of the
 * string value in case of text/PI/Comments nodes
 *
 * Returns the number of location children
 */
static int
xmlXPtrNbLocChildren(xmlNodePtr node) {
    int ret = 0;
    if (node == NULL)
	return(-1);
    switch (node->type) {
        case XML_HTML_DOCUMENT_NODE:
        case XML_DOCUMENT_NODE:
        case XML_ELEMENT_NODE:
	    node = node->children;
	    while (node != NULL) {
		if (node->type == XML_ELEMENT_NODE)
		    ret++;
		node = node->next;
	    }
	    break;
        case XML_ATTRIBUTE_NODE:
	    return(-1);

        case XML_PI_NODE:
        case XML_COMMENT_NODE:
        case XML_TEXT_NODE:
        case XML_CDATA_SECTION_NODE:
        case XML_ENTITY_REF_NODE:
	    ret = xmlStrlen(node->content);
	    break;
	default:
	    return(-1);
    }
    return(ret);
}

/**
 * xmlXPtrHereFunction:
 * @ctxt:  the XPointer Parser context
 * @nargs:  the number of args
 *
 * Function implementing here() operation 
 * as described in 5.4.3
 */
void
xmlXPtrHereFunction(xmlXPathParserContextPtr ctxt, int nargs) {
    CHECK_ARITY(0);

    if (ctxt->context->here == NULL)
	XP_ERROR(XPTR_SYNTAX_ERROR);
    
    valuePush(ctxt, xmlXPtrNewLocationSetNodes(ctxt->context->here, NULL));
}

/**
 * xmlXPtrOriginFunction:
 * @ctxt:  the XPointer Parser context
 * @nargs:  the number of args
 *
 * Function implementing origin() operation 
 * as described in 5.4.3
 */
void
xmlXPtrOriginFunction(xmlXPathParserContextPtr ctxt, int nargs) {
    CHECK_ARITY(0);

    if (ctxt->context->origin == NULL)
	XP_ERROR(XPTR_SYNTAX_ERROR);
    
    valuePush(ctxt, xmlXPtrNewLocationSetNodes(ctxt->context->origin, NULL));
}

/**
 * xmlXPtrStartPointFunction:
 * @ctxt:  the XPointer Parser context
 * @nargs:  the number of args
 *
 * Function implementing start-point() operation 
 * as described in 5.4.3
 * ----------------
 * location-set start-point(location-set)
 *
 * For each location x in the argument location-set, start-point adds a
 * location of type point to the result location-set. That point represents
 * the start point of location x and is determined by the following rules:
 *
 * - If x is of type point, the start point is x.
 * - If x is of type range, the start point is the start point of x.
 * - If x is of type root, element, text, comment, or processing instruction,
 * - the container node of the start point is x and the index is 0.
 * - If x is of type attribute or namespace, the function must signal a
 *   syntax error.
 * ----------------
 *
 */
void
xmlXPtrStartPointFunction(xmlXPathParserContextPtr ctxt, int nargs) {
    xmlXPathObjectPtr tmp, obj, point;
    xmlLocationSetPtr newset = NULL;
    xmlLocationSetPtr oldset = NULL;

    CHECK_ARITY(1);
    if ((ctxt->value == NULL) ||
	((ctxt->value->type != XPATH_LOCATIONSET) &&
	 (ctxt->value->type != XPATH_NODESET)))
        XP_ERROR(XPATH_INVALID_TYPE)

    obj = valuePop(ctxt);
    if (obj->type == XPATH_NODESET) {
	/*
	 * First convert to a location set
	 */
	tmp = xmlXPtrNewLocationSetNodeSet(obj->nodesetval);
	xmlXPathFreeObject(obj);
	obj = tmp;
    }

    newset = xmlXPtrLocationSetCreate(NULL);
    if (newset == NULL) {
	xmlXPathFreeObject(obj);
        XP_ERROR(XPATH_MEMORY_ERROR);
    }
    oldset = (xmlLocationSetPtr) obj->user;
    if (oldset != NULL) {
	int i;

	for (i = 0; i < oldset->locNr; i++) {
	    tmp = oldset->locTab[i];
	    if (tmp == NULL)
		continue;
	    point = NULL;
	    switch (tmp->type) {
		case XPATH_POINT:
		    point = xmlXPtrNewPoint(tmp->user, tmp->index);
		    break;
		case XPATH_RANGE: {
		    xmlNodePtr node = tmp->user;
		    if (node != NULL) {
			if (node->type == XML_ATTRIBUTE_NODE) {
			    /* TODO: Namespace Nodes ??? */
			    xmlXPathFreeObject(obj);
			    xmlXPtrFreeLocationSet(newset);
			    XP_ERROR(XPTR_SYNTAX_ERROR);
			}
			point = xmlXPtrNewPoint(node, tmp->index);
		    }
		    break;
	        }
		default:
		    /*** Should we raise an error ?
		    xmlXPathFreeObject(obj);
		    xmlXPathFreeObject(newset);
		    XP_ERROR(XPATH_INVALID_TYPE)
		    ***/
		    break;
	    }
            if (point != NULL)
		xmlXPtrLocationSetAdd(newset, point);
	}
    }
    xmlXPathFreeObject(obj);
    valuePush(ctxt, xmlXPtrWrapLocationSet(newset));
}

/**
 * xmlXPtrEndPointFunction:
 * @ctxt:  the XPointer Parser context
 * @nargs:  the number of args
 *
 * Function implementing end-point() operation 
 * as described in 5.4.3
 * ----------------------------
 * location-set end-point(location-set)
 *
 * For each location x in the argument location-set, end-point adds a
 * location of type point to the result location-set. That point represents
 * the end point of location x and is determined by the following rules:
 *
 * - If x is of type point, the resulting point is x.
 * - If x is of type range, the resulting point is the end point of x.
 * - If x is of type root or element, the container node of the resulting
 *   point is x and the index is the number of location children of x.
 * - If x is of type text, comment, or processing instruction, the container
 *   node of the resulting point is x and the index is the length of the
 *   string-value of x.
 * - If x is of type attribute or namespace, the function must signal a
 *   syntax error.
 * ----------------------------
 */
void
xmlXPtrEndPointFunction(xmlXPathParserContextPtr ctxt, int nargs) {
    xmlXPathObjectPtr tmp, obj, point;
    xmlLocationSetPtr newset = NULL;
    xmlLocationSetPtr oldset = NULL;

    CHECK_ARITY(1);
    if ((ctxt->value == NULL) ||
	((ctxt->value->type != XPATH_LOCATIONSET) &&
	 (ctxt->value->type != XPATH_NODESET)))
        XP_ERROR(XPATH_INVALID_TYPE)

    obj = valuePop(ctxt);
    if (obj->type == XPATH_NODESET) {
	/*
	 * First convert to a location set
	 */
	tmp = xmlXPtrNewLocationSetNodeSet(obj->nodesetval);
	xmlXPathFreeObject(obj);
	obj = tmp;
    }

    newset = xmlXPtrLocationSetCreate(NULL);
    oldset = (xmlLocationSetPtr) obj->user;
    if (oldset != NULL) {
	int i;

	for (i = 0; i < oldset->locNr; i++) {
	    tmp = oldset->locTab[i];
	    if (tmp == NULL)
		continue;
	    point = NULL;
	    switch (tmp->type) {
		case XPATH_POINT:
		    point = xmlXPtrNewPoint(tmp->user, tmp->index);
		    break;
		case XPATH_RANGE: {
		    xmlNodePtr node = tmp->user2;
		    if (node != NULL) {
			if (node->type == XML_ATTRIBUTE_NODE) {
			    /* TODO: Namespace Nodes ??? */
			    xmlXPathFreeObject(obj);
			    xmlXPtrFreeLocationSet(newset);
			    XP_ERROR(XPTR_SYNTAX_ERROR);
			}
			point = xmlXPtrNewPoint(node, tmp->index2);
		    } else if (tmp->user == NULL) {
			point = xmlXPtrNewPoint(node,
				       xmlXPtrNbLocChildren(node));
		    }
		    break;
	        }
		default:
		    /*** Should we raise an error ?
		    xmlXPathFreeObject(obj);
		    xmlXPathFreeObject(newset);
		    XP_ERROR(XPATH_INVALID_TYPE)
		    ***/
		    break;
	    }
            if (point != NULL)
		xmlXPtrLocationSetAdd(newset, point);
	}
    }
    xmlXPathFreeObject(obj);
    valuePush(ctxt, xmlXPtrWrapLocationSet(newset));
}


/**
 * xmlXPtrCoveringRange:
 * @ctxt:  the XPointer Parser context
 * @loc:  the location for which the covering range must be computed
 *
 * A covering range is a range that wholly encompasses a location
 * Section 5.3.3. Covering Ranges for All Location Types
 *        http://www.w3.org/TR/xptr#N2267
 *
 * Returns a new location or NULL in case of error
 */
static xmlXPathObjectPtr
xmlXPtrCoveringRange(xmlXPathParserContextPtr ctxt, xmlXPathObjectPtr loc) {
    if (loc == NULL)
	return(NULL);
    if ((ctxt == NULL) || (ctxt->context == NULL) ||
	(ctxt->context->doc == NULL))
	return(NULL);
    switch (loc->type) {
        case XPATH_POINT:
	    return(xmlXPtrNewRange(loc->user, loc->index,
			           loc->user, loc->index));
        case XPATH_RANGE:
	    if (loc->user2 != NULL) {
		return(xmlXPtrNewRange(loc->user, loc->index,
			              loc->user2, loc->index2));
	    } else {
		xmlNodePtr node = (xmlNodePtr) loc->user;