/*
neon XML parser interface
Copyright (C) 1999-2007, Joe Orton <joe@manyfish.co.uk>
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
MA 02111-1307, USA
*/
#ifndef NE_XML_H
#define NE_XML_H
#include <sys/types.h> /* for size_t */
#include "ne_defs.h"
NE_BEGIN_DECLS
/* The neon XML interface filters a streamed XML tree through a stack
* of SAX "handlers". A handler is made up of three callbacks
* (start-element, char-data, end-element). Each start-element event
* is passed to each handler in the stack in turn until one until one
* accepts the element. This handler then receives subsequent
* char-data and end-element events for the element.
*
* For each new start-element event, the search up the handler stack
* begins with the handler for the parent element (for the root
* element, at the base of the stack).
*
* For each accepted element, a "state" integer is stored, which is
* passed to the corresponding char-data and end-element callbacks for
* the element. This integer is also passed to the start-element
* callback of child elements so they can determine context.
*
* If no handler in the stack accepts a particular element, it (and
* its children, if any) is ignored. */
#define NE_XML_DECLINE (0)
#define NE_XML_ABORT (-1)
/* A start-element callback for element with given namespace/name.
* The callback may return:
* <0 => abort the parse (NE_XML_ABORT)
* 0 => decline this element (NE_XML_DECLINE)
* >0 => accept this element; value is state for this element.
*
* The 'parent' integer is the state returned by the handler of the
* parent element. The attributes array gives name/value pairs
* in atts[n] and atts[n+1] from n=0 up to atts[n]==NULL. */
typedef int ne_xml_startelm_cb(void *userdata, int parent,
const char *nspace, const char *name,
const char **atts);
/* state for the root element */
#define NE_XML_STATEROOT (0)
/* Character data callback; may return non-zero to abort the parse. */
typedef int ne_xml_cdata_cb(void *userdata, int state,
const char *cdata, size_t len);
/* End element callback; may return non-zero to abort the parse. */
typedef int ne_xml_endelm_cb(void *userdata, int state,
const char *nspace, const char *name);
typedef struct ne_xml_parser_s ne_xml_parser;
/* Create an XML parser. */
ne_xml_parser *ne_xml_create(void);
/* Push a new handler on the stack of parser 'p'. 'cdata' and/or
* 'endelm' may be NULL; startelm must be non-NULL. */
void ne_xml_push_handler(ne_xml_parser *p,
ne_xml_startelm_cb *startelm,
ne_xml_cdata_cb *cdata,
ne_xml_endelm_cb *endelm,
void *userdata);
/* ne_xml_failed returns non-zero if there was an error during
* parsing, or zero if the parse completed successfully. The return
* value is equal to that of the last ne_xml_parse() call for this
* parser object. */
int ne_xml_failed(ne_xml_parser *p);
/* Set error string for parser. (The string may be truncated
* internally). */
void ne_xml_set_error(ne_xml_parser *p, const char *msg);
/* Return the error string (and never NULL). After ne_xml_failed
* returns >0, this will describe the parse error. Otherwise it will
* be a default error string. */
const char *ne_xml_get_error(ne_xml_parser *p);
/* Parse the given block of input of length len. Parser must be
* called with len=0 to signify the end of the document (for that
* case, the block argument is ignored). Returns zero on success, or
* non-zero on error: for an XML syntax error, a positive number is
* returned; if parsing is aborted by a caller-supplied callback, that
* callback's return value is returned. */
int ne_xml_parse(ne_xml_parser *p, const char *block, size_t len);
/* As ne_xml_parse, casting (ne_xml_parser *)userdata internally.
* (This function can be passed to ne_add_response_body_reader) */
int ne_xml_parse_v(void *userdata, const char *block, size_t len);
/* Return current line of document during parsing or after parsing is
* complete. */
int ne_xml_currentline(ne_xml_parser *p);
/* From a start_element callback which was passed 'attrs' using given
* parser, return attribute of given name and namespace. If nspace is
* NULL, no namespace resolution is performed. Note that this call is
* context-specific; if called outside a start_element callback,
* behaviour is undefined. */
const char *ne_xml_get_attr(ne_xml_parser *parser,
const char **attrs, const char *nspace,
const char *name);
/* From a start_element callback, resolve a given XML Namespace
* prefix, if defined. Given a non-NULL prefix, returns the namespace
* URI which corresponds to the prefix 'prefix' (of length 'length'),
* or NULL if no such namespace prefix is defined. Given a NULL
* prefix, returns the default namespace URI or the empty string if
* none is defined. Note that this call is context-specific; if
* called outside a start_element callback, behaviour is undefined. */
const char *ne_xml_resolve_nspace(ne_xml_parser *parser,
const char *prefix, size_t length);
/* Return the encoding of the document being parsed. May return NULL
* if no encoding is defined or if the XML declaration has not yet
* been parsed. */
const char *ne_xml_doc_encoding(const ne_xml_parser *p);
/* Destroy the parser object. */
void ne_xml_destroy(ne_xml_parser *p);
/* A utility interface for mapping {nspace, name} onto an integer. */
struct ne_xml_idmap {
const char *nspace, *name;
int id;
};
/* Return the size of an idmap array */
#define NE_XML_MAPLEN(map) (sizeof(map) / sizeof(struct ne_xml_idmap))
/* Return the 'id' corresponding to {nspace, name}, or zero. */
int ne_xml_mapid(const struct ne_xml_idmap map[], size_t maplen,
const char *nspace, const char *name);
/* media type, appropriate for adding to a Content-Type header */
#define NE_XML_MEDIA_TYPE "application/xml"
NE_END_DECLS
#endif /* NE_XML_H */