/* $Id: navigator.h,v 1.4 2004/11/04 17:17:25 jonas Exp $ */#ifndef EL__DOCUMENT_DOM_NAVIGATOR_H#define EL__DOCUMENT_DOM_NAVIGATOR_H#include "document/document.h"#include "document/dom/node.h"#include "util/error.h"#include "util/hash.h"struct dom_navigator;enum dom_exception_code {	DOM_ERR_NONE				=  0,	DOM_ERR_INDEX_SIZE			=  1,	DOM_ERR_STRING_SIZE			=  2,	DOM_ERR_HIERARCHY_REQUEST		=  3,	DOM_ERR_WRONG_DOCUMENT			=  4,	DOM_ERR_INVALID_CHARACTER		=  5,	DOM_ERR_NO_DATA_ALLOWED			=  6,	DOM_ERR_NO_MODIFICATION_ALLOWED		=  7,	DOM_ERR_NOT_FOUND			=  8,	DOM_ERR_NOT_SUPPORTED			=  9,	DOM_ERR_INUSE_ATTRIBUTE			= 10,	/* Introduced in DOM Level 2: */	DOM_ERR_INVALID_STATE			= 11,	DOM_ERR_SYNTAX				= 12,	DOM_ERR_INVALID_MODIFICATION		= 13,	DOM_ERR_NAMESPACE			= 14,	DOM_ERR_INVALID_ACCESS			= 15,};typedef struct dom_node *	(*dom_navigator_callback_T)(struct dom_navigator *, struct dom_node *, void *);#define DOM_NAVIGATOR_MAX_DEPTH	4096struct dom_navigator_state {	struct dom_node *node;	struct dom_node_list *list;	size_t index;	dom_navigator_callback_T callback;	void *data;};/* The DOM navigator is a convenient way to traverse DOM trees. Also it * maintains needed state info and is therefore also a holder of the current * context since the navigator is used to when the DOM tree is manipulated. */struct dom_navigator {	/* The stack of nodes */	struct dom_navigator_state *states;	size_t depth;	unsigned char *state_objects;	size_t object_size;	/* If some operation failed this member will signal the error code */	enum dom_exception_code exception;	/* Parser and document specific stuff */	dom_navigator_callback_T callbacks[DOM_NODES];	void *data;};#define dom_navigator_has_parents(nav) \	((nav)->states && (nav)->depth > 0)static inline struct dom_navigator_state *get_dom_navigator_state(struct dom_navigator *navigator, int top_offset){	assertm(navigator->depth - 1 - top_offset >= 0,		"Attempting to access invalid state");	return &navigator->states[navigator->depth - 1 - top_offset];}#define get_dom_navigator_parent(nav)	get_dom_navigator_state(nav, 1)#define get_dom_navigator_top(nav)	get_dom_navigator_state(nav, 0)/* The state iterators do not include the bottom state */#define foreach_dom_state(nav, item, pos)			\	for ((pos) = 1; (pos) < (nav)->depth; (pos)++)		\		if (((item) = &(nav)->states[(pos)]))#define foreachback_dom_state(nav, item, pos)			\	for ((pos) = (nav)->depth - 1; (pos) > 0; (pos)--)	\		if (((item) = &(nav)->states[(pos)]))/* Dive through the navigator states in search for the specified match. */static inline struct dom_navigator_state *search_dom_navigator(struct dom_navigator *navigator, enum dom_node_type type,		     unsigned char *string, uint16_t length){	struct dom_navigator_state *state;	int pos;	foreachback_dom_state (navigator, state, pos) {		struct dom_node *parent = state->node;		if (parent->type == type		    && parent->length == length		    && !strncasecmp(parent->string, string, length))			return state;	}	return NULL;}/* Life cycle functions. *//* The @object_size arg tells whether the navigator should allocate objects for each * state to be assigned to the state's @data member. Zero means no state data should * be allocated. */void init_dom_navigator(struct dom_navigator *navigator, void *data, dom_navigator_callback_T callbacks[DOM_NODES], size_t object_size);void done_dom_navigator(struct dom_navigator *navigator);/* Decends down to the given node making it the current parent *//* If an error occurs the node is free()d and NULL is returned */struct dom_node *push_dom_node(struct dom_navigator *navigator, struct dom_node *node);/* Ascends the navigator to the current parent */void pop_dom_node(struct dom_navigator *navigator);/* Ascends the navigator looking for specific parent */void pop_dom_nodes(struct dom_navigator *navigator, enum dom_node_type type,		   unsigned char *string, uint16_t length);/* Visit each node in the tree rooted at @root pre-order */void walk_dom_nodes(struct dom_navigator *navigator, struct dom_node *root);#endif