darling-libxml2/xpath.h

109 lines
3.3 KiB
C

/*
* xpath.c: interface for XML Path Language implementation
*
* Reference: W3C Working Draft 5 July 1999
* http://www.w3.org/Style/XSL/Group/1999/07/xpath-19990705.html
*
* See COPYRIGHT for the status of this software
*
* Author: Daniel.Veillard@w3.org
*/
#ifndef __XML_XPATH_H__
#define __XML_XPATH_H__
#include "tree.h"
/*
* A node-set (an unordered collection of nodes without duplicates)
*/
typedef struct xmlNodeSet {
int nodeNr; /* # of node in the set */
int nodeMax; /* allocated space */
xmlNodePtr *nodeTab; /* array of nodes in no particular order */
} xmlNodeSet, *xmlNodeSetPtr;
/*
* An expression is evaluated to yield an object, which
* has one of the following four basic types:
* - node-set
* - boolean
* - number
* - string
*/
#define XPATH_UNDEFINED 0
#define XPATH_NODESET 1
#define XPATH_BOOLEAN 2
#define XPATH_NUMBER 3
#define XPATH_STRING 4
#define XPATH_MARKER 5 /* used for func call checks */
typedef struct xmlXPathObject {
int type;
xmlNodeSetPtr nodesetval;
int boolval;
float floatval;
CHAR *stringval;
} xmlXPathObject, *xmlXPathObjectPtr;
/*
* Expression evaluation occurs with respect to a context.
* he context consists of:
* - a node (the context node)
* - a node list (the context node list)
* - a set of variable bindings
* - a function library
* - the set of namespace declarations in scope for the expression
*/
typedef struct xmlXPathContext {
xmlDocPtr doc; /* The current document */
xmlNodePtr node; /* The current node */
xmlNodeSetPtr nodelist; /* The current node list */
void *variables; /* TODO !!!! */
void *functions; /* TODO !!!! */
void *namespaces; /* TODO !!!! */
} xmlXPathContext, *xmlXPathContextPtr;
/*
* An XPath parser context, it contains pure parsing informations,
* an xmlXPathContext, and the stack of objects.
*/
typedef struct xmlXPathParserContext {
const CHAR *cur; /* the current char being parsed */
const CHAR *base; /* the full expression */
int error; /* error code */
xmlXPathContextPtr context; /* the evaluation context */
xmlXPathObjectPtr value; /* the current value */
int valueNr; /* number of values stacked */
int valueMax; /* max number of values stacked */
xmlXPathObjectPtr *valueTab; /* stack of values */
} xmlXPathParserContext, *xmlXPathParserContextPtr;
/*
* An XPath function
* The arguments (if any) are popped out of the context stack
* and the result is pushed on the stack.
*/
typedef void (*xmlXPathFunction) (xmlXPathParserContextPtr ctxt, int nargs);
/************************************************************************
* *
* Public API *
* *
************************************************************************/
xmlXPathContextPtr xmlXPathNewContext(xmlDocPtr doc, void *variables,
void *functions, void *namespaces);
void xmlXPathFreeContext(xmlXPathContextPtr ctxt);
xmlXPathObjectPtr xmlXPathEval(const CHAR *str, xmlXPathContextPtr ctxt);
void xmlXPathFreeObject(xmlXPathObjectPtr obj);
xmlXPathObjectPtr xmlXPathEvalExpression(const CHAR *str,
xmlXPathContextPtr ctxt);
#endif /* ! __XML_XPATH_H__ */