/* * Summary: XML Path Language implementation * Description: API for the XML Path Language implementation * * XML Path Language implementation * XPath is a language for addressing parts of an XML document, * designed to be used by both XSLT and XPointer * http://www.w3.org/TR/xpath * * Implements * W3C Recommendation 16 November 1999 * http://www.w3.org/TR/1999/REC-xpath-19991116 * * Copy: See Copyright for the status of this software. * * Author: Daniel Veillard */#ifndef __XML_XPATH_H__#define __XML_XPATH_H__#include <libxml/xmlversion.h>#ifdef LIBXML_XPATH_ENABLED#include <libxml/xmlerror.h>#include <libxml/tree.h>#include <libxml/hash.h>#endif /* LIBXML_XPATH_ENABLED */#if defined(LIBXML_XPATH_ENABLED) || defined(LIBXML_SCHEMAS_ENABLED)#ifdef __cplusplusextern "C" {#endif#endif /* LIBXML_XPATH_ENABLED or LIBXML_SCHEMAS_ENABLED */#ifdef LIBXML_XPATH_ENABLEDtypedef struct _xmlXPathContext xmlXPathContext;typedef xmlXPathContext *xmlXPathContextPtr;typedef struct _xmlXPathParserContext xmlXPathParserContext;typedef xmlXPathParserContext *xmlXPathParserContextPtr;/** * The set of XPath error codes. */typedef enum { XPATH_EXPRESSION_OK = 0, XPATH_NUMBER_ERROR, XPATH_UNFINISHED_LITERAL_ERROR, XPATH_START_LITERAL_ERROR, XPATH_VARIABLE_REF_ERROR, XPATH_UNDEF_VARIABLE_ERROR, XPATH_INVALID_PREDICATE_ERROR, XPATH_EXPR_ERROR, XPATH_UNCLOSED_ERROR, XPATH_UNKNOWN_FUNC_ERROR, XPATH_INVALID_OPERAND, XPATH_INVALID_TYPE, XPATH_INVALID_ARITY, XPATH_INVALID_CTXT_SIZE, XPATH_INVALID_CTXT_POSITION, XPATH_MEMORY_ERROR, XPTR_SYNTAX_ERROR, XPTR_RESOURCE_ERROR, XPTR_SUB_RESOURCE_ERROR, XPATH_UNDEF_PREFIX_ERROR, XPATH_ENCODING_ERROR, XPATH_INVALID_CHAR_ERROR, XPATH_INVALID_CTXT} xmlXPathError;/* * A node-set (an unordered collection of nodes without duplicates). */typedef struct _xmlNodeSet xmlNodeSet;typedef xmlNodeSet *xmlNodeSetPtr;struct _xmlNodeSet { int nodeNr; /* number of nodes in the set */ int nodeMax; /* size of the array as allocated */ xmlNodePtr *nodeTab; /* array of nodes in no particular order */ /* @@ with_ns to check wether namespace nodes should be looked at @@ */};/* * An expression is evaluated to yield an object, which * has one of the following four basic types: * - node-set * - boolean * - number * - string * * @@ XPointer will add more types ! */typedef enum { XPATH_UNDEFINED = 0, XPATH_NODESET = 1, XPATH_BOOLEAN = 2, XPATH_NUMBER = 3, XPATH_STRING = 4, XPATH_POINT = 5, XPATH_RANGE = 6, XPATH_LOCATIONSET = 7, XPATH_USERS = 8, XPATH_XSLT_TREE = 9 /* An XSLT value tree, non modifiable */} xmlXPathObjectType;typedef struct _xmlXPathObject xmlXPathObject;typedef xmlXPathObject *xmlXPathObjectPtr;struct _xmlXPathObject { xmlXPathObjectType type; xmlNodeSetPtr nodesetval; int boolval; double floatval; xmlChar *stringval; void *user; int index; void *user2; int index2;};/** * xmlXPathConvertFunc: * @obj: an XPath object * @type: the number of the target type * * A conversion function is associated to a type and used to cast * the new type to primitive values. * * Returns -1 in case of error, 0 otherwise */typedef int (*xmlXPathConvertFunc) (xmlXPathObjectPtr obj, int type);/* * Extra type: a name and a conversion function. */typedef struct _xmlXPathType xmlXPathType;typedef xmlXPathType *xmlXPathTypePtr;struct _xmlXPathType { const xmlChar *name; /* the type name */ xmlXPathConvertFunc func; /* the conversion function */};/* * Extra variable: a name and a value. */typedef struct _xmlXPathVariable xmlXPathVariable;typedef xmlXPathVariable *xmlXPathVariablePtr;struct _xmlXPathVariable { const xmlChar *name; /* the variable name */ xmlXPathObjectPtr value; /* the value */};/** * xmlXPathEvalFunc: * @ctxt: an XPath parser context * @nargs: the number of arguments passed to the function * * An XPath evaluation function, the parameters are on the XPath context stack. */typedef void (*xmlXPathEvalFunc)(xmlXPathParserContextPtr ctxt, int nargs);/* * Extra function: a name and a evaluation function. */typedef struct _xmlXPathFunct xmlXPathFunct;typedef xmlXPathFunct *xmlXPathFuncPtr;struct _xmlXPathFunct { const xmlChar *name; /* the function name */ xmlXPathEvalFunc func; /* the evaluation function */};/** * xmlXPathAxisFunc: * @ctxt: the XPath interpreter context * @cur: the previous node being explored on that axis * * An axis traversal function. To traverse an axis, the engine calls * the first time with cur == NULL and repeat until the function returns * NULL indicating the end of the axis traversal. * * Returns the next node in that axis or NULL if at the end of the axis. */typedef xmlXPathObjectPtr (*xmlXPathAxisFunc) (xmlXPathParserContextPtr ctxt, xmlXPathObjectPtr cur);/* * Extra axis: a name and an axis function. */typedef struct _xmlXPathAxis xmlXPathAxis;typedef xmlXPathAxis *xmlXPathAxisPtr;struct _xmlXPathAxis { const xmlChar *name; /* the axis name */ xmlXPathAxisFunc func; /* the search function */};/** * xmlXPathFunction: * @ctxt: the XPath interprestation context * @nargs: the number of arguments * * An XPath function. * The arguments (if any) are popped out from the context stack * and the result is pushed on the stack. */typedef void (*xmlXPathFunction) (xmlXPathParserContextPtr ctxt, int nargs);/* * Function and Variable Lookup. *//** * xmlXPathVariableLookupFunc: * @ctxt: an XPath context * @name: name of the variable * @ns_uri: the namespace name hosting this variable * * Prototype for callbacks used to plug variable lookup in the XPath * engine. * * Returns the XPath object value or NULL if not found. */typedef xmlXPathObjectPtr (*xmlXPathVariableLookupFunc) (void *ctxt, const xmlChar *name, const xmlChar *ns_uri);/** * xmlXPathFuncLookupFunc: * @ctxt: an XPath context * @name: name of the function * @ns_uri: the namespace name hosting this function * * Prototype for callbacks used to plug function lookup in the XPath * engine. * * Returns the XPath function or NULL if not found. */typedef xmlXPathFunction (*xmlXPathFuncLookupFunc) (void *ctxt, const xmlChar *name, const xmlChar *ns_uri);/** * xmlXPathFlags: * Flags for XPath engine compilation and runtime *//** * XML_XPATH_CHECKNS: * * check namespaces at compilation */#define XML_XPATH_CHECKNS (1<<0)/** * XML_XPATH_NOVAR: * * forbid variables in expression */#define XML_XPATH_NOVAR (1<<1)/** * xmlXPathContext: * * 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 * Following the switch to hash tables, this need to be trimmed up at * the next binary incompatible release. */struct _xmlXPathContext { xmlDocPtr doc; /* The current document */ xmlNodePtr node; /* The current node */ int nb_variables_unused; /* unused (hash table) */ int max_variables_unused; /* unused (hash table) */ xmlHashTablePtr varHash; /* Hash table of defined variables */ int nb_types; /* number of defined types */ int max_types; /* max number of types */ xmlXPathTypePtr types; /* Array of defined types */ int nb_funcs_unused; /* unused (hash table) */ int max_funcs_unused; /* unused (hash table) */ xmlHashTablePtr funcHash; /* Hash table of defined funcs */ int nb_axis; /* number of defined axis */ int max_axis; /* max number of axis */ xmlXPathAxisPtr axis; /* Array of defined axis */ /* the namespace nodes of the context node */ xmlNsPtr *namespaces; /* Array of namespaces */ int nsNr; /* number of namespace in scope */ void *user; /* function to free */ /* extra variables */ int contextSize; /* the context size */ int proximityPosition; /* the proximity position */ /* extra stuff for XPointer */ int xptr; /* it this an XPointer context */ xmlNodePtr here; /* for here() */ xmlNodePtr origin; /* for origin() */ /* the set of namespace declarations in scope for the expression */ xmlHashTablePtr nsHash; /* The namespaces hash table */ xmlXPathVariableLookupFunc varLookupFunc;/* variable lookup func */ void *varLookupData; /* variable lookup data */ /* Possibility to link in an extra item */ void *extra; /* needed for XSLT */ /* The function name and URI when calling a function */ const xmlChar *function; const xmlChar *functionURI; /* function lookup function and data */ xmlXPathFuncLookupFunc funcLookupFunc;/* function lookup func */ void *funcLookupData; /* function lookup data */ /* temporary namespace lists kept for walking the namespace axis */ xmlNsPtr *tmpNsList; /* Array of namespaces */ int tmpNsNr; /* number of namespace in scope */ /* error reporting mechanism */ void *userData; /* user specific data block */ xmlStructuredErrorFunc error; /* the callback in case of errors */ xmlError lastError; /* the last error */ xmlNodePtr debugNode; /* the source node XSLT */ /* dictionnary */ xmlDictPtr dict; /* dictionnary if any */ int flags; /* flags to control compilation */};/* * The structure of a compiled expression form is not public. */typedef struct _xmlXPathCompExpr xmlXPathCompExpr;typedef xmlXPathCompExpr *xmlXPathCompExprPtr;/** * xmlXPathParserContext: * * An XPath parser context. It contains pure parsing informations, * an xmlXPathContext, and the stack of objects. */struct _xmlXPathParserContext { const xmlChar *cur; /* the current char being parsed */ const xmlChar *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 */ xmlXPathCompExprPtr comp; /* the precompiled expression */ int xptr; /* it this an XPointer expression */ xmlNodePtr ancestor; /* used for walking preceding axis */};/************************************************************************ * * * Public API * * * ************************************************************************//** * Objects and Nodesets handling */XMLPUBVAR double xmlXPathNAN;XMLPUBVAR double xmlXPathPINF;XMLPUBVAR double xmlXPathNINF;/* These macros may later turn into functions *//** * xmlXPathNodeSetGetLength: * @ns: a node-set * * Implement a functionality similar to the DOM NodeList.length. * * Returns the number of nodes in the node-set. */#define xmlXPathNodeSetGetLength(ns) ((ns) ? (ns)->nodeNr : 0)/** * xmlXPathNodeSetItem: * @ns: a node-set * @index: index of a node in the set * * Implements a functionality similar to the DOM NodeList.item(). * * Returns the xmlNodePtr at the given @index in @ns or NULL if * @index is out of range (0 to length-1) */#define xmlXPathNodeSetItem(ns, index) \ ((((ns) != NULL) && \ ((index) >= 0) && ((index) < (ns)->nodeNr)) ? \ (ns)->nodeTab[(index)] \ : NULL)/** * xmlXPathNodeSetIsEmpty: * @ns: a node-set * * Checks whether @ns is empty or not. * * Returns %TRUE if @ns is an empty node-set. */#define xmlXPathNodeSetIsEmpty(ns) \ (((ns) == NULL) || ((ns)->nodeNr == 0) || ((ns)->nodeTab == NULL))XMLPUBFUN void XMLCALL xmlXPathFreeObject (xmlXPathObjectPtr obj);XMLPUBFUN xmlNodeSetPtr XMLCALL xmlXPathNodeSetCreate (xmlNodePtr val);XMLPUBFUN void XMLCALL xmlXPathFreeNodeSetList (xmlXPathObjectPtr obj);XMLPUBFUN void XMLCALL xmlXPathFreeNodeSet (xmlNodeSetPtr obj);XMLPUBFUN xmlXPathObjectPtr XMLCALL xmlXPathObjectCopy (xmlXPathObjectPtr val);XMLPUBFUN int XMLCALL xmlXPathCmpNodes (xmlNodePtr node1, xmlNodePtr node2);/** * Conversion functions to basic types. */XMLPUBFUN int XMLCALL xmlXPathCastNumberToBoolean (double val);XMLPUBFUN int XMLCALL xmlXPathCastStringToBoolean (const xmlChar * val);XMLPUBFUN int XMLCALL xmlXPathCastNodeSetToBoolean(xmlNodeSetPtr ns);XMLPUBFUN int XMLCALL xmlXPathCastToBoolean (xmlXPathObjectPtr val);XMLPUBFUN double XMLCALL xmlXPathCastBooleanToNumber (int val);XMLPUBFUN double XMLCALL xmlXPathCastStringToNumber (const xmlChar * val);XMLPUBFUN double XMLCALL xmlXPathCastNodeToNumber (xmlNodePtr node);XMLPUBFUN double XMLCALL xmlXPathCastNodeSetToNumber (xmlNodeSetPtr ns);XMLPUBFUN double XMLCALL xmlXPathCastToNumber (xmlXPathObjectPtr val);XMLPUBFUN xmlChar * XMLCALL xmlXPathCastBooleanToString (int val);XMLPUBFUN xmlChar * XMLCALL xmlXPathCastNumberToString (double val);XMLPUBFUN xmlChar * XMLCALL xmlXPathCastNodeToString (xmlNodePtr node);XMLPUBFUN xmlChar * XMLCALL xmlXPathCastNodeSetToString (xmlNodeSetPtr ns);XMLPUBFUN xmlChar * XMLCALL xmlXPathCastToString (xmlXPathObjectPtr val);XMLPUBFUN xmlXPathObjectPtr XMLCALL xmlXPathConvertBoolean (xmlXPathObjectPtr val);XMLPUBFUN xmlXPathObjectPtr XMLCALL xmlXPathConvertNumber (xmlXPathObjectPtr val);XMLPUBFUN xmlXPathObjectPtr XMLCALL xmlXPathConvertString (xmlXPathObjectPtr val);/** * Context handling. */XMLPUBFUN xmlXPathContextPtr XMLCALL xmlXPathNewContext (xmlDocPtr doc);XMLPUBFUN void XMLCALL xmlXPathFreeContext (xmlXPathContextPtr ctxt);/** * Evaluation functions. */XMLPUBFUN long XMLCALL xmlXPathOrderDocElems (xmlDocPtr doc);XMLPUBFUN xmlXPathObjectPtr XMLCALL xmlXPathEval (const xmlChar *str, xmlXPathContextPtr ctx);XMLPUBFUN xmlXPathObjectPtr XMLCALL xmlXPathEvalExpression (const xmlChar *str, xmlXPathContextPtr ctxt);XMLPUBFUN int XMLCALL xmlXPathEvalPredicate (xmlXPathContextPtr ctxt, xmlXPathObjectPtr res);/** * Separate compilation/evaluation entry points. */XMLPUBFUN xmlXPathCompExprPtr XMLCALL xmlXPathCompile (const xmlChar *str);XMLPUBFUN xmlXPathCompExprPtr XMLCALL xmlXPathCtxtCompile (xmlXPathContextPtr ctxt, const xmlChar *str);XMLPUBFUN xmlXPathObjectPtr XMLCALL xmlXPathCompiledEval (xmlXPathCompExprPtr comp, xmlXPathContextPtr ctx);XMLPUBFUN void XMLCALL xmlXPathFreeCompExpr (xmlXPathCompExprPtr comp);#endif /* LIBXML_XPATH_ENABLED */#if defined(LIBXML_XPATH_ENABLED) || defined(LIBXML_SCHEMAS_ENABLED)XMLPUBFUN void XMLCALL xmlXPathInit (void);XMLPUBFUN int XMLCALL xmlXPathIsNaN (double val);XMLPUBFUN int XMLCALL xmlXPathIsInf (double val);#ifdef __cplusplus}#endif#endif /* LIBXML_XPATH_ENABLED or LIBXML_SCHEMAS_ENABLED*/#endif /* ! __XML_XPATH_H__ */