xpath.c

xml开源解析代码.版本为libxml2-2.6.29,可支持GB3212.网络消息发送XML时很有用.

	    xmlXPathDebugObjUsageRequested(ctxt, XPATH_NODESET);
#endif
	    return(ret);	    
	}
    }
	    
    return(xmlXPathWrapNodeSet(val));
    
}

/**
 * xmlXPathCacheWrapString:
 * @ctxt: the XPath context
 * @val:  the xmlChar * value
 *
 * This is the cached version of xmlXPathWrapString().
 * Wraps the @val string into an XPath object.
 *
 * Returns the created or reused object.
 */
static xmlXPathObjectPtr
xmlXPathCacheWrapString(xmlXPathContextPtr ctxt, xmlChar *val)
{    
    if ((ctxt != NULL) && (ctxt->cache != NULL)) {
	xmlXPathContextCachePtr cache = (xmlXPathContextCachePtr) ctxt->cache;

	if ((cache->stringObjs != NULL) &&
	    (cache->stringObjs->number != 0))
	{
	
	    xmlXPathObjectPtr ret;
	    
	    ret = (xmlXPathObjectPtr)
		cache->stringObjs->items[--cache->stringObjs->number];
	    ret->type = XPATH_STRING;
	    ret->stringval = val;
#ifdef XP_DEBUG_OBJ_USAGE
	    xmlXPathDebugObjUsageRequested(ctxt, XPATH_STRING);
#endif
	    return(ret);
	} else if ((cache->miscObjs != NULL) &&
	    (cache->miscObjs->number != 0))
	{
	    xmlXPathObjectPtr ret;
	    /*
	    * Fallback to misc-cache.
	    */
	    ret = (xmlXPathObjectPtr)
		cache->miscObjs->items[--cache->miscObjs->number];

	    ret->type = XPATH_STRING;
	    ret->stringval = val;
#ifdef XP_DEBUG_OBJ_USAGE
	    xmlXPathDebugObjUsageRequested(ctxt, XPATH_STRING);
#endif
	    return(ret);
	}
    }
    return(xmlXPathWrapString(val));
}

/**
 * xmlXPathCacheNewNodeSet:
 * @ctxt: the XPath context
 * @val:  the NodePtr value
 *
 * This is the cached version of xmlXPathNewNodeSet().
 * Acquire an xmlXPathObjectPtr of type NodeSet and initialize
 * it with the single Node @val
 *
 * Returns the created or reused object.
 */
static xmlXPathObjectPtr
xmlXPathCacheNewNodeSet(xmlXPathContextPtr ctxt, xmlNodePtr val)
{
    if ((ctxt != NULL) && (ctxt->cache)) {
	xmlXPathContextCachePtr cache = (xmlXPathContextCachePtr) ctxt->cache;

	if ((cache->nodesetObjs != NULL) &&
	    (cache->nodesetObjs->number != 0))
	{	
	    xmlXPathObjectPtr ret;
	    /*
	    * Use the nodset-cache.
	    */	    
	    ret = (xmlXPathObjectPtr)
		cache->nodesetObjs->items[--cache->nodesetObjs->number];
	    ret->type = XPATH_NODESET;
	    ret->boolval = 0;
	    if (val) {		
		if ((ret->nodesetval->nodeMax == 0) ||
		    (val->type == XML_NAMESPACE_DECL))
		{
		    xmlXPathNodeSetAddUnique(ret->nodesetval, val);		
		} else {
		    ret->nodesetval->nodeTab[0] = val;
		    ret->nodesetval->nodeNr = 1;
		}
	    }
#ifdef XP_DEBUG_OBJ_USAGE
	    xmlXPathDebugObjUsageRequested(ctxt, XPATH_NODESET);
#endif
	    return(ret);
	} else if ((cache->miscObjs != NULL) &&
	    (cache->miscObjs->number != 0))
	{
	    xmlXPathObjectPtr ret;
	    /*
	    * Fallback to misc-cache.
	    */

	    ret = (xmlXPathObjectPtr)
		cache->miscObjs->items[--cache->miscObjs->number];

	    ret->type = XPATH_NODESET;
	    ret->boolval = 0;
	    ret->nodesetval = xmlXPathNodeSetCreate(val);
#ifdef XP_DEBUG_OBJ_USAGE
	    xmlXPathDebugObjUsageRequested(ctxt, XPATH_NODESET);
#endif
	    return(ret);
	}
    }
    return(xmlXPathNewNodeSet(val));
}

/**
 * xmlXPathCacheNewCString:
 * @ctxt: the XPath context
 * @val:  the char * value
 *
 * This is the cached version of xmlXPathNewCString().
 * Acquire an xmlXPathObjectPtr of type string and of value @val
 *
 * Returns the created or reused object.
 */
static xmlXPathObjectPtr
xmlXPathCacheNewCString(xmlXPathContextPtr ctxt, const char *val)
{    
    if ((ctxt != NULL) && (ctxt->cache)) {
	xmlXPathContextCachePtr cache = (xmlXPathContextCachePtr) ctxt->cache;

	if ((cache->stringObjs != NULL) &&
	    (cache->stringObjs->number != 0))
	{	
	    xmlXPathObjectPtr ret;
	    
	    ret = (xmlXPathObjectPtr)
		cache->stringObjs->items[--cache->stringObjs->number];

	    ret->type = XPATH_STRING;
	    ret->stringval = xmlStrdup(BAD_CAST val);
#ifdef XP_DEBUG_OBJ_USAGE
	    xmlXPathDebugObjUsageRequested(ctxt, XPATH_STRING);
#endif
	    return(ret);
	} else if ((cache->miscObjs != NULL) &&
	    (cache->miscObjs->number != 0))
	{
	    xmlXPathObjectPtr ret;

	    ret = (xmlXPathObjectPtr)
		cache->miscObjs->items[--cache->miscObjs->number];

	    ret->type = XPATH_STRING;
	    ret->stringval = xmlStrdup(BAD_CAST val);
#ifdef XP_DEBUG_OBJ_USAGE
	    xmlXPathDebugObjUsageRequested(ctxt, XPATH_STRING);
#endif
	    return(ret);
	}
    }
    return(xmlXPathNewCString(val));
}

/**
 * xmlXPathCacheNewString:
 * @ctxt: the XPath context
 * @val:  the xmlChar * value
 *
 * This is the cached version of xmlXPathNewString().
 * Acquire an xmlXPathObjectPtr of type string and of value @val
 *
 * Returns the created or reused object.
 */
static xmlXPathObjectPtr
xmlXPathCacheNewString(xmlXPathContextPtr ctxt, const xmlChar *val)
{    
    if ((ctxt != NULL) && (ctxt->cache)) {
	xmlXPathContextCachePtr cache = (xmlXPathContextCachePtr) ctxt->cache;

	if ((cache->stringObjs != NULL) &&
	    (cache->stringObjs->number != 0))
	{	
	    xmlXPathObjectPtr ret;
	    
	    ret = (xmlXPathObjectPtr)
		cache->stringObjs->items[--cache->stringObjs->number];
	    ret->type = XPATH_STRING;
	    if (val != NULL)
		ret->stringval = xmlStrdup(val);
	    else
		ret->stringval = xmlStrdup((const xmlChar *)"");
#ifdef XP_DEBUG_OBJ_USAGE
	    xmlXPathDebugObjUsageRequested(ctxt, XPATH_STRING);
#endif
	    return(ret);
	} else if ((cache->miscObjs != NULL) &&
	    (cache->miscObjs->number != 0))
	{
	    xmlXPathObjectPtr ret;

	    ret = (xmlXPathObjectPtr)
		cache->miscObjs->items[--cache->miscObjs->number];

	    ret->type = XPATH_STRING;
	    if (val != NULL)
		ret->stringval = xmlStrdup(val);
	    else
		ret->stringval = xmlStrdup((const xmlChar *)"");
#ifdef XP_DEBUG_OBJ_USAGE
	    xmlXPathDebugObjUsageRequested(ctxt, XPATH_STRING);
#endif
	    return(ret);
	}
    }
    return(xmlXPathNewString(val));
}

/**
 * xmlXPathCacheNewBoolean:
 * @ctxt: the XPath context
 * @val:  the boolean value
 *
 * This is the cached version of xmlXPathNewBoolean().
 * Acquires an xmlXPathObjectPtr of type boolean and of value @val
 *
 * Returns the created or reused object.
 */
static xmlXPathObjectPtr
xmlXPathCacheNewBoolean(xmlXPathContextPtr ctxt, int val)
{    
    if ((ctxt != NULL) && (ctxt->cache)) {
	xmlXPathContextCachePtr cache = (xmlXPathContextCachePtr) ctxt->cache;

	if ((cache->booleanObjs != NULL) &&
	    (cache->booleanObjs->number != 0))
	{	
	    xmlXPathObjectPtr ret;
	    
	    ret = (xmlXPathObjectPtr)
		cache->booleanObjs->items[--cache->booleanObjs->number];
	    ret->type = XPATH_BOOLEAN;
	    ret->boolval = (val != 0);
#ifdef XP_DEBUG_OBJ_USAGE
	    xmlXPathDebugObjUsageRequested(ctxt, XPATH_BOOLEAN);
#endif
	    return(ret);
	} else if ((cache->miscObjs != NULL) &&
	    (cache->miscObjs->number != 0))
	{
	    xmlXPathObjectPtr ret;

	    ret = (xmlXPathObjectPtr)
		cache->miscObjs->items[--cache->miscObjs->number];

	    ret->type = XPATH_BOOLEAN;
	    ret->boolval = (val != 0);
#ifdef XP_DEBUG_OBJ_USAGE
	    xmlXPathDebugObjUsageRequested(ctxt, XPATH_BOOLEAN);
#endif
	    return(ret);
	}
    }
    return(xmlXPathNewBoolean(val));
}

/**
 * xmlXPathCacheNewFloat:
 * @ctxt: the XPath context
 * @val:  the double value
 *
 * This is the cached version of xmlXPathNewFloat().
 * Acquires an xmlXPathObjectPtr of type double and of value @val
 *
 * Returns the created or reused object.
 */
static xmlXPathObjectPtr
xmlXPathCacheNewFloat(xmlXPathContextPtr ctxt, double val)
{
     if ((ctxt != NULL) && (ctxt->cache)) {
	xmlXPathContextCachePtr cache = (xmlXPathContextCachePtr) ctxt->cache;

	if ((cache->numberObjs != NULL) &&
	    (cache->numberObjs->number != 0))
	{	
	    xmlXPathObjectPtr ret;
	    
	    ret = (xmlXPathObjectPtr)
		cache->numberObjs->items[--cache->numberObjs->number];
	    ret->type = XPATH_NUMBER;
	    ret->floatval = val;
#ifdef XP_DEBUG_OBJ_USAGE
	    xmlXPathDebugObjUsageRequested(ctxt, XPATH_NUMBER);
#endif
	    return(ret);
	} else if ((cache->miscObjs != NULL) &&
	    (cache->miscObjs->number != 0))
	{
	    xmlXPathObjectPtr ret;

	    ret = (xmlXPathObjectPtr)
		cache->miscObjs->items[--cache->miscObjs->number];

	    ret->type = XPATH_NUMBER;
	    ret->floatval = val;
#ifdef XP_DEBUG_OBJ_USAGE
	    xmlXPathDebugObjUsageRequested(ctxt, XPATH_NUMBER);
#endif
	    return(ret);
	}
    }
    return(xmlXPathNewFloat(val));
}

/**
 * xmlXPathCacheConvertString:
 * @ctxt: the XPath context
 * @val:  an XPath object
 *
 * This is the cached version of xmlXPathConvertString().
 * Converts an existing object to its string() equivalent
 *
 * Returns a created or reused object, the old one is freed (cached)
 *         (or the operation is done directly on @val)
 */

static xmlXPathObjectPtr
xmlXPathCacheConvertString(xmlXPathContextPtr ctxt, xmlXPathObjectPtr val) {
    xmlChar *res = NULL;    

    if (val == NULL)
	return(xmlXPathCacheNewCString(ctxt, ""));

    switch (val->type) {
    case XPATH_UNDEFINED:
#ifdef DEBUG_EXPR
	xmlGenericError(xmlGenericErrorContext, "STRING: undefined\n");
#endif
	break;
    case XPATH_NODESET:
    case XPATH_XSLT_TREE:
	res = xmlXPathCastNodeSetToString(val->nodesetval);
	break;
    case XPATH_STRING:
	return(val);
    case XPATH_BOOLEAN:
	res = xmlXPathCastBooleanToString(val->boolval);
	break;
    case XPATH_NUMBER:
	res = xmlXPathCastNumberToString(val->floatval);
	break;
    case XPATH_USERS:
    case XPATH_POINT:
    case XPATH_RANGE:
    case XPATH_LOCATIONSET:
	TODO;
	break;
    }
    xmlXPathReleaseObject(ctxt, val);
    if (res == NULL)
	return(xmlXPathCacheNewCString(ctxt, ""));
    return(xmlXPathCacheWrapString(ctxt, res));
}

/**
 * xmlXPathCacheObjectCopy:
 * @ctxt: the XPath context
 * @val:  the original object
 *
 * This is the cached version of xmlXPathObjectCopy().
 * Acquire a copy of a given object
 *
 * Returns a created or reused created object.
 */
static xmlXPathObjectPtr
xmlXPathCacheObjectCopy(xmlXPathContextPtr ctxt, xmlXPathObjectPtr val)
{
    if (val == NULL)
	return(NULL);

    if (XP_HAS_CACHE(ctxt)) {
	switch (val->type) {
	    case XPATH_NODESET:
		return(xmlXPathCacheWrapNodeSet(ctxt,
		    xmlXPathNodeSetMerge(NULL, val->nodesetval)));
	    case XPATH_STRING:
		return(xmlXPathCacheNewString(ctxt, val->stringval));
	    case XPATH_BOOLEAN:
		return(xmlXPathCacheNewBoolean(ctxt, val->boolval));
	    case XPATH_NUMBER:
		return(xmlXPathCacheNewFloat(ctxt, val->floatval));
	    default:
		break;
	}
    }
    return(xmlXPathObjectCopy(val));
}

/**
 * xmlXPathCacheConvertBoolean:
 * @ctxt: the XPath context
 * @val:  an XPath object
 *
 * This is the cached version of xmlXPathConvertBoolean().
 * Converts an existing object to its boolean() equivalent
 *
 * Returns a created or reused object, the old one is freed (or the operation
 *         is done directly on @val)
 */
static xmlXPathObjectPtr
xmlXPathCacheConvertBoolean(xmlXPathContextPtr ctxt, xmlXPathObjectPtr val) {
    xmlXPathObjectPtr ret;
    
    if (val == NULL)
	return(xmlXPathCacheNewBoolean(ctxt, 0));
    if (val->type == XPATH_BOOLEAN)
	return(val);
    ret = xmlXPathCacheNewBoolean(ctxt, xmlXPathCastToBoolean(val));
    xmlXPathReleaseObject(ctxt, val);
    return(ret);
}

/**
 * xmlXPathCacheConvertNumber:
 * @ctxt: the XPath context
 * @val:  an XPath object
 *
 * This is the cached version of xmlXPathConvertNumber().
 * Converts an existing object to its number() equivalent
 *
 * Returns a created or reused object, the old one is freed (or the operation
 *         is done directly on @val)
 */
static xmlXPathObjectPtr
xmlXPathCacheConvertNumber(xmlXPathContextPtr ctxt, xmlXPathObjectPtr val) {
    xmlXPathObjectPtr ret;
    
    if (val == NULL)
	return(xmlXPathCacheNewFloat(ctxt, 0.0));
    if (val->type == XPATH_NUMBER)
	return(val);
    ret = xmlXPathCacheNewFloat(ctxt, xmlXPathCastToNumber(val));
    xmlXPathReleaseObject(ctxt, val);
    return(ret);
}

/************************************************************************
 *									*
 * 		Parser stacks related functions and macros		*
 *									*
 ************************************************************************/

/**
 * valuePop:
 * @ctxt: an XPath evaluation context
 *
 * Pops the top XPath object from the value stack
 *
 * Returns the XPath object just removed
 */
xmlXPathObjectPtr
valuePop(xmlXPathParserContextPtr ctxt)
{
    xmlXPathObjectPtr ret;

    if ((ctxt == NULL) || (ctxt->valueNr <= 0))
        return (NULL);
    ctxt->valueNr--;
    if (ctxt->valueNr > 0)
        ctxt->value = ctxt->valueTab[ctxt->valueNr - 1];
    else
        ctxt->value = NU