libraptor(3)


NAME

   libraptor - Raptor RDF parser and serializer library

SYNOPSIS

   #include <raptor.h>

   raptor_init();
   raptor_parser *p=raptor_new_parser("rdfxml");
   raptor_set_statement_handler(p,NULL,print_triples);
   raptor_uri *file_uri=raptor_new_uri("http://example.org/");
   raptor_parse_file(p,file_uri,base_uri);
   raptor_parse_uri(p,uri,NULL);
   raptor_free_parser(p);
   raptor_free_uri(file_uri);
   raptor_finish();

   cc file.c -lraptor

DESCRIPTION

   The  Raptor library provides a high-level interface to a set of parsers
   and serializers that  generate  Resource  Description  Framework  (RDF)
   triples by parsing syntaxes or serialize the triples into syntaxes.

   The  supported  parsing  syntaxes  include  RDF/XML, N-Triples, Turtle,
   TRiG, RSS tag soup (including all RSS and Atoms), GRDDL, RDFa  and  the
   serializing  syntaxes include RDF/XML (3 varieties), N-Triples, Turtle,
   RSS 1.0, Atom 1.0, GraphViz DOT and RDF/JSON.  The RDF/XML  parser  can
   use  either  expat  or  libxml  XML parsers for providing the SAX event
   stream.  The library functions are arranged in an object-oriented style
   with  constructors,  destructors  and method calls.  The statements and
   error messages are delivered via callback functions.

   Raptor contains a URI-reference parsing and resolving  (not  retrieval)
   class  (raptor_uri)  sufficient  for dealing with URI-references inside
   RDF.  This functionality is modular and can be  transparently  replaced
   with another existing and compatible URI implementation.

   It  also  provides  a  URI-retrieval  class  (raptor_www)  for wrapping
   existing library such as libcurl, libxml2 or BSD libfetch that provides
   full  or  partial  retrieval  of  data  from  URIs  and  an  I/O stream
   abstraction (raptor_iostream) for supportin serializing to a variety of
   outputs.

   Raptor  uses  Unicode  strings  for RDF literals and URIs and preserves
   them throughout the library.  It uses the UTF-8 encoding of Unicode  at
   the  API  for  passing in or returning Unicode strings.  It is intended
   that   the   preservation   of   Unicode   for   URIs   will    support
   Internationalized  Resource  Identifiers  (IRIs)  which are still under
   development and standardisation.

LIBRARY INITIALISATION AND CLEANUP

   raptor_init()

   raptor_finish()
          Initialise and cleanup the library.  These must be called before
          any raptor class such as raptor_parser, raptor_uri is created or
          used.  Note: as of 1.4.19 these are  wrappers  around  a  static
          instance  of  the  new  raptor_world  class.  In Raptor 2.0 this
          initialisation and cleanup method will be removed.

   void                       raptor_set_libxslt_security_preferences(void
   *security_preferences)
          Set libxslt security preferences object.

   void raptor_set_libxml_flags(int flags)
          Set       libxml       flags       from       the       choices:
          RAPTOR_LIBXML_FLAGS_GENERIC_ERROR_SAVE: save/restore the  libxml
          generic       error      handler      when      parsing      and
          RAPTOR_LIBXML_FLAGS_STRUCTURED_ERROR_SAVE:   save/restore    the
          libxml structured error handler when parsing.

PARSER CLASS

   This  class  provides  the  functionality  of turning syntaxes into RDF
   triples - RDF parsing.

PARSER CONSTRUCTORS

   raptor_parser* raptor_new_parser(name)
          Create a new raptor parser object for the parser with name  name
          currently  either  "rdfxml",  "turtle" or "rss-tag-soup" for the
          RSS Tag Soup parser.

   raptor_parser*  raptor_new_parser_for_content(raptor_uri  *uri,   const
   char  *mime_type,  const  unsigned  char  *buffer,  size_t  len,  const
   unsigned char *identifier)
          Create a new raptor parser object for a syntax identified by URI
          uri,  MIME  type  mime_type, some initial content buffer of size
          len  or   content   with   identifier   identifier.    See   the
          raptor_guess_parser_name description for further details.

PARSER DESTRUCTOR

   void raptor_free_parser(raptor_parser *parser)
          Destroy a Raptor parser object.

PARSER MESSAGE CALLBACK METHODS

   Several  methods  can  be  registered  for  the  parser  that  return a
   variable-argument message in the style of printf(3).  These also return
   a  raptor_locator  that  can  contain  URI, file, line, column and byte
   counts of where the message is about. This structure can be  used  with
   the  raptor_format_locator, raptor_print_locator functions below or the
   structures fields directly, which are defined in raptor.h

   void   raptor_set_fatal_error_handler(raptor_parser*    parser,    void
   *user_data, raptor_message_handler handler)
          Set the parser fatal error handler callback.

   void  raptor_set_error_handler(raptor_parser*  parser, void *user_data,
   raptor_message_handler handler)
          Set the parser non-fatal error handler callback.

   void raptor_set_warning_handler(raptor_parser* parser, void *user_data,
   raptor_message_handler handler)
          Set the parser warning message handler callback.

   raptor_set_namespace_handler(raptor_parser*  parser,  void*  user_data,
   raptor_namespace_handler handler)
          Set the namespace declaration handler callback.

PARSER STATEMENT CALLBACK METHOD

   The parser allows the registration of a callback function to return the
   statements to the application.

   void     raptor_set_statement_handler(raptor_parser*    parser,    void
   *user_data, raptor_statement_handler handler)
          Set  the  statement  callback  function  for  the  parser.   The
          raptor_statement  structure  is defined in raptor.h and includes
          fields for the subject,  predicate,  object  of  the  statements
          along with their types and for literals, language and datatype.

PARSER PARSING METHODS

   These  methods  perform  the  entire parsing in one method.  Statements
   warnings, errors and fatal errors  are  delivered  via  the  registered
   statement, error etc. handler functions.

   In  both  of  these  methods,  the base URI is required for the RDF/XML
   parser (name "rdfxml") and  Turtle  parser  (name  "turtle").   The  N-
   Triples parser (name "ntriples") or RSS Tag Soup parser (name "rss-tag-
   soup") do not use this.

   int   raptor_parse_file(raptor_parser*   parser,    raptor_uri    *uri,
   raptor_uri *base_uri)
          Parse the given filename (a URI like file:filename) according to
          the optional base URI base_uri.   If  uri  is  NULL,  read  from
          standard input and base_uri is then required.

   int raptor_parse_file_stream(raptor_parser* parser, FILE* stream, const
   char* filename, raptor_uri *base_uri)
          Parse the given  C  FILE*  stream  according  to  the  base  URI
          base_uri (required).  filename is optional and if given, is used
          for error messages via the raptor_locator structure.

   int   raptor_parse_uri(raptor_parser*   parser,     raptor_uri*    uri,
   raptor_uri *base_uri)
          Parse the URI according to the base URI base_uri, or NULL if not
          needed.  If no base URI is given, the uri is used.  This  method
          depends  on  the  raptor_www  subsystem  (see  WWW Class section
          below) and an existing underlying URI  retrieval  implementation
          such as libcurl, libxml or BSD libfetch to retrieve the content.

PARSER CHUNKED PARSING METHODS

   These  methods  perform  the  parsing  in  parts by working on multiple
   chunks of memory  passed  by  the  application.   Statements  warnings,
   errors  and  fatal  errors  are delivered via the registered statement,
   error etc. handler functions.

   int raptor_start_parse(raptor_parser* parser, const char *uri)
          Start a parse of chunked content with the base URI uri  or  NULL
          if  not needed.  The base URI is required for the RDF/XML parser
          (name "rdfxml") and  Turtle  parser  (name  "turtle").   The  N-
          Triples  parser  (name  "ntriples") or RSS Tag Soup parser (name
          "rss-tag-soup") do not use this.

   int  raptor_parse_chunk(raptor_parser*  parser,   const  unsigned  char
   *buffer, size_t len, int is_end)
          Parse  the memory at buffer of size len returning statements via
          the statement handler  callback.   If  is_end  is  non-zero,  it
          indicates  the  end of the parsing stream.  This method can only
          be called after raptor_start_parse().

PARSER UTILITY METHODS

   const char* raptor_get_mime_type(raptor_parser* rdf_parser)
          Return the MIME type for the parser.

   void raptor_set_parser_strict(raptor_parser *parser, int is_strict)
          Set the parser to strict (is_strict not zero) or  lax  (default)
          mode.   The  detail  of  the  strictness  can  be  controlled by
          raptor_set_feature.

   int raptor_set_feature(raptor_parser *parser,  raptor_feature  feature,
   int value)
          Set a parser feature feature to a particular value.  Returns non
          0 on failure or if the feature is unknown.  The current  defined
          parser features are:
            Feature                                 Values
            RAPTOR_FEATURE_ALLOW_BAGID              Boolean (non 0 true)
            RAPTOR_FEATURE_ALLOW_NON_NS_ATTRIBUTES  Boolean (non 0 true)
            RAPTOR_FEATURE_ALLOW_OTHER_PARSETYPES   Boolean (non 0 true)
            RAPTOR_FEATURE_ALLOW_RDF_TYPE_RDF_LIST  Boolean (non 0 true)
            RAPTOR_FEATURE_ASSUME_IS_RDF            Boolean (non 0 true)
            RAPTOR_FEATURE_CHECK_RDF_ID             Boolean (non 0 true)
            RAPTOR_FEATURE_HTML_LINK                Boolean (non 0 true)
            RAPTOR_FEATURE_HTML_TAG_SOUP            Boolean (non 0 true)
            RAPTOR_FEATURE_MICROFORMATS             Boolean (non 0 true)
            RAPTOR_FEATURE_NON_NFC_FATAL            Boolean (non 0 true)
            RAPTOR_FEATURE_NORMALIZE_LANGUAGE       Boolean (non 0 true)
            RAPTOR_FEATURE_NO_NET                   Boolean (non 0 true)
            RAPTOR_FEATURE_RELATIVE_URIS            Boolean (non 0 true)
            RAPTOR_FEATURE_SCANNING                 Boolean (non 0 true)
            RAPTOR_FEATURE_WARN_OTHER_PARSETYPES    Boolean (non 0 true)
            RAPTOR_FEATURE_WWW_TIMEOUT              Integer
            RAPTOR_FEATURE_WWW_HTTP_CACHE_CONTROL   String
            RAPTOR_FEATURE_WWW_HTTP_USER_AGENT      String

   If  the  allow_bagid  feature  is  true (default true) then the RDF/XML
   parser will support the rdf:bagID attribute that was removed  from  the
   RDF/XML  language  when it was revised.  This support may be removed in
   future.

   If the allow_non_ns_attributes feature is true (default true), then the
   RDF/XML  parser will allow non-XML namespaced attributes to be accepted
   as well as rdf: namespaced ones.  For example, 'about' and 'ID' will be
   interpreted as if they were rdf:about and rdf:ID respectively.

   If  the  allow_other_parsetypes feature is true (default true) then the
   RDF/XML parser will allow unknown parsetypes to  be  present  and  will
   pass them on to the user.  Unimplemented at present.

   If the allow_rdf_type_rdf_list feature is true (default false) then the
   RDF/XML parser will generate the idList rdf:type rdf:List triple in the
   handling of rdf:parseType="Collection".  This triple was removed during
   the revising of RDF/XML after collections were initially added.

   If the assume_is_rdf feature is true (default false), then the  RDF/XML
   parser  will  assume  the  content is RDF/XML, not require that rdf:RDF
   root element, and immediately interpret the content as RDF/XML.

   If the check_rdf_id feature is true (default true) then  rdf:ID  values
   will be checked for duplicates and cause an error if found.

   if  the  html_link  feature  is  true  (default  true),  look  for head
   &lt;link&gt; to type rdf/xml for GRDDL parser

   If the html_tag_soup feature is true (default true),  use  a  lax  HTML
   parser if an XML parser fails when read HTML for GRDDL parser.

   If   the   microformats  feature  is  true  (default  true),  look  for
   microformats for GRDDL parser.

   If the non_nfc_fatal feature  is  true  (default  false)  then  illegal
   Unicode Normal Form C in literals will give a fatal error, otherwise it
   gives a warning.

   If the normalize_language feature  is  true  (default  true)  then  XML
   language values such as from xml:lang will be normalized to lowercase.

   If the no_net feature is true (default false) then network requests are
   denied.

   If the scanning feature is  true  (default  false),  then  the  RDF/XML
   parser  will look for embedded rdf:RDF elements inside the XML content,
   and not require that the XML start with an rdf:RDF root element.

   If the www_timeout feature is set to an integer larger than 0, it  sets
   the  timeout  in  seconds  for  internal WWW URI requests for the GRDDL
   parser.

   If the www_http_cache_control feature is set to a string value (default
   none),  it  is  sent  as the value of the HTTP Cache-Control: header in
   requests.

   If the www_http_user_agent feature is set to a string value, it is sent
   as the value of the HTTP User-Agent: header in requests.

   raptor_parser_set_feature_string(raptor_parser  *parser, raptor_feature
   feature, const unsigned char *value)
          Set a parser feature  feature  to  a  particular  string  value.
          Returns  non  0  on  failure  or if the feature is unknown.  The
          current defined parser features are given in  raptor_set_feature
          and  at  present  only  take integer values. If an integer value
          feature is set with this function, value is  interpreted  as  an
          integer and then that value is used.

   int raptor_get_feature(raptor_parser* parser, raptor_feature feature)
          Get  parser  feature integer values.  The allowed feature values
          and types are given under raptor_features_enumerate.

   const  unsigned  char*   raptor_parser_get_feature_string(raptor_parser
   *parser, raptor_feature feature)
          Get parser feature string values. The allowed feature values and
          types are given under raptor_features_enumerate.

   unsigned int raptor_get_feature_count(void)
          Get the count of features  defined.   Prefered  to  the  compile
          time-only  symbol  RAPTOR_FEATURE_LAST which returns the maximum
          value, not the count.  Added raptor_get_need_base_uri

   int raptor_feature_value_type(const raptor_feature feature)
          Get a raptor feature value tyype - integer or string.

   raptor_locator* raptor_get_locator(raptor_parser* rdf_parser)
          Return the current raptor_locator object for the  parser.   This
          is  a  public  structure  defined  in  raptor.h that can be used
          directly, or formatted via raptor_print_locator.

   void raptor_get_name(raptor_parser *parser)
          Return the string short name for the parser.

   void raptor_get_label(raptor_parser *parser)
          Return a string label for the parser.

   void           raptor_set_default_generate_id_parameters(raptor_parser*
   rdf_parser, char *prefix, int base)
          Control the default method for generation of IDs for blank nodes
          and bags.  The method uses a short string prefix and an  integer
          base  to generate the identifier which is not guaranteed to be a
          strict concatenation.  If prefix is NULL, the default  is  used.
          If base is less than 1, it is initialised to 1.

   void    raptor_set_generate_id_handler(raptor_parser*    parser,   void
   *user_data, raptor_generate_id_handler handler)
          Allow full customisation of  the  generated  IDs  by  setting  a
          callback   handler  and  associated  user_data  that  is  called
          whenever a blank node or bag identifier is required.  The memory
          returned  is  deallocated  inside  raptor.  Some systems require
          this to be allocated inside the same library, in which case  the
          raptor_alloc_memory function may be useful.

   void         raptor_parser_set_uri_filter(raptor_parser*        parser,
   raptor_uri_filter_func filter, void* user_data)
          Set the URI filter function filter  for  URIs  retrieved  during
          parsing by the the raptor_parser.

   int raptor_get_need_base_uri(raptor_parser* rdf_parser)
          Get  a  boolean  whether  this  parser needs a base URI to start
          parsing.

   unsigned  char*  raptor_parser_generate_id(raptor_parser*   rdf_parser,
   raptor_genid_type type)
          Generate   an   ID   for   a   parser   of   type  type,  either
          RAPTOR_GENID_TYPE_BNODEID or RAPTOR_GENID_TYPE_BAGID.  This uses
          any configuration set by raptor_set_generate_id_handler.

   void  raptor_set_graph_handler(raptor_parser*  parser, void* user_data,
   raptor_graph_handler handler)
          Set the graph handler callback.

   raptor_world* raptor_parser_get_world(raptor_parser* rdf_parser)
          Get the world object for the given rdf_parser.

PARSER UTILITY FUNCTIONS

   int raptor_parsers_enumerate(const unsigned  int  counter,  const  char
   **name, const char **label)
          Return  the  parser name/label for a parser with a given integer
          counter, returning non-zero if no such  parser  at  that  offset
          exists.  The counter should start from 0 and be incremented by 1
          until the function returns non-zero.

   int raptor_syntaxes_enumerate(const unsigned int  counter,  const  char
   **name, const char **label, const char **mime_type, const unsigned char
   **uri-string)
          Return the name, label, mime type or URI string  (all  optional)
          for a parser syntax with a given integer counter, returning non-
          zero if no such  syntax  parser  at  that  offset  exists.   The
          counter  should  start  from 0 and be incremented by 1 until the
          function returns non-zero.

   int raptor_features_enumerate(const raptor_feature feature, const  char
   **name, raptor_uri **uri, const char **label)
          Return  the  name, URI, string label (all optional) for a parser
          feature, returning non-zero if no such feature exists.

   Raptor  features  have  URIs  that  are  constructed   from   the   URI
   http://feature.librdf.org/raptor-  and  the name so for example feature
   scanForRDF has URI http://feature.librdf.org/raptor-scanForRDF

   int raptor_syntax_name_check(const char *name)
          Check name is a known syntax name.

   const  char*  raptor_guess_parser_name(raptor_uri  *uri,   const   char
   *mime_type,  const  unsigned  char  *buffer, size_t len, const unsigned
   char *identifier)
          Guess a parser name for a syntax identified  by  URI  uri,  MIME
          type  mime_type, some initial content buffer of size len or with
          content identifier identifier.   All  of  these  parameters  are
          optional  and  only  used  if not NULL.  The parser is chosen by
          scoring the hints that are given.

   raptor_feature raptor_feature_from_uri(raptor_uri *uri)
          Turn a URI uri into a raptor feature identifier, or  <0  if  the
          feature    is   unknown.    The   URIs   are   described   below
          raptor_set_feature.

STATEMENT UTILITY FUNCTIONS

   int   raptor_statement_compare(const   raptor_statement   *s1,    const
   raptor_statement *s2)
          Compare two statements and return an ordering between them.

   void  raptor_print_statement(const  raptor_statement*  const statement,
   FILE *stream)
          Print a raptor statement object in a simple format for debugging
          only.  The format of this output is not guaranteed to remain the
          same between releases.

   void     raptor_print_statement_as_ntriples(const     raptor_statement*
   statement, FILE *stream)
          Print  a  raptor statement object in N-Triples format, using all
          the   escapes   as    defined    in    http://www.w3.org/TR/rdf-
          testcases/#ntriples                   http://www.w3.org/TR/rdf-
          testcases/#ntriples

   raptor_statement_part_as_counted_string(const        void        *term,
   raptor_identifier_type   type,   raptor_uri*   literal_datatype,  const
   unsigned char *literal_language, size_t* len_p)

   char*      raptor_statement_part_as_string(const      void       *term,
   raptor_identifier_type   type,   raptor_uri*   literal_datatype,  const
   unsigned char *literal_language)
          Turns part of raptor statement into N-Triples format, using  all
          the    escapes    as    defined   in   http://www.w3.org/TR/rdf-
          testcases/#ntriples                   http://www.w3.org/TR/rdf-
          testcases/#ntriples  The  part  (subject, predicate, object) of
          the raptor_statement  is  passed  in  as  term,  the  part  type
          (subject_type,  predicate_type,  object_type)  is  passed  in as
          type.  When the part is  a  literal,  the  literal_datatype  and
          literal_language   fields   are  set,  otherwise  NULL  (usually
          object_datatype, object_literal_language).

          If raptor_statement_part_as_counted_string is used,  the  length
          of the returned string is stored in *len_p if not NULL.

LOCATOR UTILITY FUNCTIONS

   int  raptor_format_locator(char *buffer, size_t length, raptor_locator*
   locator)
          This method takes a raptor_locator object as passed to an error,
          warning or other handler callback and formats it into the buffer
          of  size  length  bytes.   If  buffer  is  NULL  or  length   is
          insufficient  for the size of the formatted locator, returns the
          number of additional bytes required in the buffer to  write  the
          locator.

          In particular, if this form is used:
            length=raptor_format_locator(NULL,  0, locator) it will return
          in length the size of a buffer that can be allocated for locator
          and a second call will perform the formatting:
            raptor_format_locator(buffer, length, locator)

   void raptor_print_locator(FILE *stream, raptor_locator* locator)
          This method takes a raptor_locator object as passed to an error,
          warning or other handler callback, formats and prints it to  the
          given stdio stream.

   int raptor_locator_line(raptor_locator *locator)
          Returns  the  line  number  in  a locator structure or <0 if not
          available.

   int raptor_locator_column(raptor_locator *locator)
          Returns the column number in a locator structure or  <0  if  not
          available.

   int raptor_locator_byte(raptor_locator *locator)
          Returns  the  byte  offset  in  a locator structure or <0 if not
          available.

   const char * raptor_locator_file(raptor_locator *locator)
          Returns the filename in a  locator  structure  or  NULL  if  not
          available.  Note the returned pointer is to a shared string that
          must be copied if needed.

   const char * raptor_locator_uri(raptor_locator *locator)
          Returns the URI string in a locator structure  or  NULL  if  not
          available.   Note this does not return a raptor_uri* pointer and
          the returned pointer is to a shared string that must  be  copied
          if needed.

N-TRIPLES UTILITY FUNCTIONS

   void  raptor_print_ntriples_string(FILE*  stream,  const  char* string,
   const char delim)
          This is a standalone  function  that  prints  the  given  string
          according   to   N-Triples   escaping  rules,  expecting  to  be
          terminated by delimiter delim which is usually either ', " or <.
          If a null delimiter \0 is given, no extra escaping is performed.

   int raptor_iostream_write_string_ntriples(raptor_iostream *iostr, const
   unsigned char *string, size_t len, const char delim)
          Write an N-Triples  encoded  version  of  the  given  string  to
          iostream iostr.  If delim is given, that is the ending delimeter
          of the encoded string and it will be escaped in  the  output  as
          appropriate.   Useful  delim  values  are ', " and >.  If a null
          delimiter \0 is given, no extra escaping is performed.

   int raptor_iostream_write_string_python(raptor_iostream  *iostr,  const
   unsigned char *string, size_t len, const char delim, int flags)
          Write  string  encoded to an iostream according to the delimeter
          delim and encoding flags.  The  flag  value  selects  formatting
          according to the appropriate Python-related languages such as N-
          Triples (0), Turtle (1), Turtle long  quoted  string  (2),  JSON
          (3).

   void  raptor_iostream_write_statement_ntriples(raptor_iostream*  iostr,
   const raptor_statement *statement)
          Write an  N-Triples  encoded  version  of  the  raptor_statement
          statement to iostream iostr.

   void  raptor_iostream_write_string_turtle(raptor_iostream* iostr, const
   unsigned char* string, size_t len)
          DEPRECATED in 1.4.17 -  use  raptor_iostream_write_string_python
          instead.   Write  an UTF-8 string of length len using the Turtle
          "longString" triple quoting format to the iostream iostr.

   const char*  raptor_ntriples_term_as_string  (raptor_ntriples_term_type
   term)
          Deprecated, for internal use.

XML UTILITY FUNCTIONS

   int  raptor_xml_any_escape_string(const  unsigned  char* string, size_t
   len, unsigned char* buffer, size_t length, char quote, int xml_version,
   raptor_simple_message_handler error_handler, void* error_data)

   int  raptor_xml_escape_string(const  unsigned char *string, size_t len,
   unsigned    char    *buffer,     size_t     length,     char     quote,
   raptor_message_handler error_handler, void *error_data)
          Apply  the  XML  escaping  rules to the string given in (string,
          len) into the buffer of size length.  If  quote  is  given,  the
          escaped  content  is  for  an  XML attribute and the appropriate
          quote character XML element content (CDATA).   The error_handler
          method  along with error_data allow error reporting to be given.
          If buffer is NULL, returns the size of the  buffer  required  to
          escape.   Otherwise the return value is the number of bytes used
          or <0 on failure.

          When an xml_version argument is present and has a value 10  (XML
          1.0)  or  11  (XML  1.1) then that version is used.  The default
          with no argument is to generate XML 1.0.

   int       raptor_iostream_write_xml_any_escaped_string(raptor_iostream*
   iostr,  const  unsigned  char*  string,  size_t  len,  char  quote, int
   xml_version,   raptor_simple_message_handler    error_handler,    void*
   error_data)

   int   raptor_iostream_write_xml_escaped_string(raptor_iostream*  iostr,
   const   unsigned   char    *string,    size_t    len,    char    quote,
   raptor_simple_message_handler error_handler, void *error_data)
          Write  an  XML-escaped  version  of the string given in (string,
          len) to iostream iostr.  If quote is given, the escaped  content
          is  for  an XML attribute and the appropriate quote character is
          used,  otherwise  it  is  XML  element  content  (CDATA).    The
          error_handler method along with error_data allow error reporting
          to be given.

          When an xml_version argument is present and has a value 10  (XML
          1.0)  or  11  (XML  1.1) then that version is used.  The default
          with no argument is to generate XML 1.0.

   int raptor_xml_name_check(const unsigned char *string,  size_t  length,
   int xml_version)
          Check  that the given string of length bytes is a legal XML name
          according to XML 1.0 or XML 1.1.  xml_version is set to 10 or 11
          respectively.  Returns non-zero if the name is legal.

MEMORY UTILITY FUNCTIONS

   void raptor_free_memory(void *ptr)
          Free  memory  allocated  inside  raptor.   Some  systems require
          memory allocated in a library  to  be  deallocated  inside  that
          library.   This  function  can be used in that situation to free
          memory allocated by raptor, such  as  the  result  of  the  _to_
          methods     that     return    allocated    memory    such    as
          raptor_uri_to_filename,                    raptor_uri_to_string,
          raptor_uri_to_relative_counted_uri_string,
          raptor_uri_to_relative_uri_string                             or
          raptor_new_namespace_parts_from_string.

   void* raptor_alloc_memory(size_t size)
          Allocate memory inside the raptor library.  Some systems require
          memory allocated in a library  to  be  deallocated  inside  that
          library.   This  function  can  be  used  in  that  situation to
          allocate memory for raptor to free later,  such  as  inside  the
          handler  function  declared  with raptor_set_generate_id_handler
          which returns new memory.

   void* raptor_calloc_memory(size_t nmemb, size_t size)
          Allocate zeroed array of  items  inside  raptor.   Some  systems
          require  memory  allocated in a library to be deallocated inside
          that library.  This function can be used in  that  situation  to
          clear  an  array  of  allocated  memory  for  raptor to use, for
          freeing later, such as inside the handler function declared with
          raptor_set_generate_id_handler which returns new memory.

UNICODE UTILITY FUNCTIONS

   int   raptor_unicode_char_to_utf8(raptor_unichar   c,   unsigned   char
   *output)
          Turn a Unicode character into UTF8 bytes in  output  of  size  c
          bytes  which  must be of sufficient size.  Returns the number of
          bytes encoded or <0 on failure.

   int raptor_utf8_to_unicode_char(raptor_unichar *output, const  unsigned
   char *input, int length)
          Decode  a  sequence  UTF8  bytes  in input of size length into a
          Unicode character in output returning the number of  bytes  used
          or <0 on failure.

   int raptor_utf8_check(const unsigned char *string, size_t length)
          Check  that  a given string is legal UTF-8 encoding and includes
          only legal  Unicode  characters  U+0  to  U+0x10ffff  inclusive.
          Returns non-0 if the string is good.

   int raptor_unicode_is_xml11_namestartchar(raptor_unichar c)

   int raptor_unicode_is_xml10_namestartchar(raptor_unichar c)

   int raptor_unicode_is_xml11_namechar(raptor_unichar c)

   int raptor_unicode_is_xml10_namechar(raptor-unichar c)
          Check  that  given  Unicode characters are allowed as XML 1.0 or
          XML   1.0   names   -   either   as   the   starting   character
          (*_namestartchar) or continuing character (*_namechar).  Returns
          non-0 if the character is allowed.

ERROR UTILITY FUNCTIONS

   void raptor_error_handlers_init(raptor_error_handlers* error_handlers)
          Initialise an  error_handlers  structure  after  the  log  level
          handlers and user data pointers have been set.

MISCELLANEOUS UTILITY FUNCTIONS

   char* raptor_vsnprintf(const char *message, va_list arguments)
          Compatibility wrapper around vsnprintf.

STATIC VARIABLES

   There are several read-only static variables in the raptor library:

   const char * const raptor_short_copyright_string
          Short copyright string, suitable for one line.

   const char * const raptor_copyright_string
          Full copyright over several lines including URLs.

   const char * const raptor_version_string
          The version as a string

   const unsigned int raptor_version_major
          The major version number as an integer.

   const unsigned int raptor_version_minor
          The minor version number as an integer.

   const unsigned int raptor_version_release
          The release version number as an integer.

   const unsigned int raptor_version_decimal
          The version number as a single decimal.

   const char * const raptor_license_string
          The license string over several lines including URLs.

   const char * const raptor_home_url_string
          The home page URL as a string.

SERIALIZER CLASS

   This  class  provides  the  functionality  of  turning RDF triples into
   syntaxes - RDF serializing.

SERIALIZER CONSTRUCTOR

   raptor_serializer* raptor_new_serializer(const char *name)
          Create a new raptor serializer object for  the  serializer  with
          name name currently either "rdfxml" or "ntriples".  or "rss-1.0"
          for the RSS 1.0 serializer.

SERIALIZER DESTRUCTOR

   void raptor_free_serializer(raptor_serializer* rdf_serializer)
          Destroy a Raptor serializer object.

SERIALIZER SERIALIZING METHODS

   int      raptor_serialize_start(raptor_serializer*      rdf_serializer,
   raptor_uri *uri, raptor_iostream *iostream)
          Start  to serialize content using the given iostream to write to
          with optional base URI uri. The iostream becomes  owned  by  the
          serializer  object  and  is  destroyed at the end of serializing
          when raptor_serialize_end() is called.  Note that  some syntaxes
          may refuse to serialize without a base URI, such as RDF/XML.

   int               raptor_serialize_start_to_iostream(raptor_serializer*
   rdf_serializer, raptor_uri* uri, raptor_iostream* iostream)
          Start to serialize content using the given iostream to write  to
          with  optional base URI uri.  The iostream does NOT become owned
          by the serializer object and the caller may continue to write to
          it  after  serializing is finished.  Note that some syntaxes may
          refuse to serialize without a base URI, such as RDF/XML.

   int               raptor_serialize_start_to_filename(raptor_serializer*
   rdf_serializer, const char *filename)
          Start  to serialize content to the file filename which is opened
          for writing. The base URI is calculated from the file name.

   int raptor_serialize_start_to_string(raptor_serializer* rdf_serializer,
   raptor_uri *uri, void **string_p, size_t *length_p)
          Start  to serialize content to a string.  string_p must point to
          a void* pointer that will be used at the end of  serializing  to
          store the newly allocated string.  length_p if not NULL, it will
          be used to store the length of the new string.  The  serializing
          is  done  with  optional  base URI uri however some syntaxes may
          refuse to serialize without a base URI, such as RDF/XML.

   int            raptor_serialize_start_to_file_handle(raptor_serializer*
   rdf_serializer, raptor_uri *uri, FILE *handle)
          Start  to  serialize  content to the already open C Standard I/O
          FILE* handle with the base URI uri, which is optional and may be
          NULL.  Note that some syntaxes may refuse to serialize without a
          base URI, such as RDF/XML.

   int raptor_serialize_statement(raptor_serializer* rdf_serializer, const
   raptor_statement *statement)
          Serialize a single statement using the serializer.

   int raptor_serialize_end(raptor_serializer* rdf_serializer)
          End  the  serializing.  This may close and delete resources used
          in serializing.  No more calls to raptor_serialize_statement  or
          raptor_serialize_end may be done at this point.

   raptor_iostream*       raptor_serializer_get_iostream(raptor_serializer
   *serializer)
          Return a pointer to the raptor_iostream* used by the serializer.

   int   raptor_serializer_set_namespace(raptor_serializer*    serializer,
   raptor_uri *uri, const char *prefix)
          Set   a  suggested  namespace  URI/prefix  mapping  for  use  in
          serializing.

SERIALIZER UTILITY METHODS

   void raptor_serializer_set_error_handler(raptor_serializer* serializer,
   void *user_data, raptor_message_handler handler)
          Set the serializer non-fatal error handler callback.

   void           raptor_serializer_set_warning_handler(raptor_serializer*
   serializer, void *user_data, raptor_message_handler handler)
          Set the serializer warning message handler callback.

   raptor_locator*        raptor_serializer_get_locator(raptor_serializer*
   rdf_serializer)
          Return  the  current  raptor_locator  object for the serializer.
          This is a public structure defined in raptor.h that can be  used
          directly, or formatted via raptor_print_locator.

   int     raptor_serializer_set_feature(raptor_serializer    *serializer,
   raptor_feature feature, int value)
          Set a serializer feature feature to a particular value.  Returns
          non  0  on  failure  or  if the feature is unknown.  The current
          defined serializer features are:
            Feature                                 Values
            RAPTOR_FEATURE_RELATIVE_URIS            Boolean (non 0 true)
            RAPTOR_FEATURE_WRITE_BASE_URI           Boolean (non 0 true)
            RAPTOR_FEATURE_START_URI                URI String
            RAPTOR_FEATURE_BNODE_BORDER             String
            RAPTOR_FEATURE_BNODE_FILL               String
            RAPTOR_FEATURE_JSON_CALLBACK            String
            RAPTOR_FEATURE_JSON_EXTRA_DATA          String
            RAPTOR_FEATURE_LITERAL_BORDER           String
            RAPTOR_FEATURE_LITERAL_FILL             String
            RAPTOR_FEATURE_RESOURCE_BORDER          String
            RAPTOR_FEATURE_RESOURCE_FILL            String
            RAPTOR_FEATURE_RSS_TRIPLES              String
            RAPTOR_FEATURE_ATOM_ENTRY_URI           String

   If  the  relative_uris  feature  is  true  (default  false)  then  when
   serialising,  preference  is  given  to  generating relative URIs where
   possible.

   If the write_base_uri feature is true (default  true)  then  the  atom,
   rdfxml,  rdfxml-abbrev  and  turtle  serializers will write an @base or
   xml:base directive in the output.

   If the start_uri feature is set to a URI it is used by  the  serializer
   to start serializing from.

   If  the  bnode_border feature is set, the DOT serializer uses it as the
   bnode border colour.

   If the bnode_fill feature is set, the DOT serializer  uses  it  as  the
   bnode fill colour.

   If the json_callback feature is set, the JSON serializers use it as the
   name of the callback to wrap the outer JSON object.

   If the json_extra_data feature is set, the JSON serializers use  it  as
   extra data inside the outer JSON object.

   If the literal_border feature is set, the DOT serializer uses it as the
   literal border colour.

   If the literal_fill feature is set, the DOT serializer uses it  as  the
   literal fill colour.

   If  the  resource_border  feature is set, the DOT serializer uses it as
   the resource border colour.

   If the resource_fill feature is set, the DOT serializer uses it as  the
   resource fill colour.

   If  the  rss_triples  feature  is  set  to the string "rdf-xml" for the
   rss-1.0 serializer or "atom-triples" for the atom serializer, it writes
   extra rdf triples into the serialized output.

   If  the  atom_entry_uri  feature  is set to a URI string, it is used to
   trigger generation of an atom entry document for the atom serializer.

   int    raptor_serializer_get_feature(raptor_serializer*     serializer,
   raptor_feature feature)
          Get   serializer   features,  the  allowed  feature  values  are
          available

   raptor_world*            raptor_serializer_get_world(raptor_serializer*
   rdf_serializer)
          Get the world object for the given rdf_serializer.

SERIALIZER UTILITY FUNCTIONS

   int raptor_serializers_enumerate(const unsigned int counter, const char
   **name, const char **label, const char **mime_type, const unsigned char
   **uri_string)
          Return  the  serializer name/label for a serializer with a given
          integer counter, returning non-zero if no such  parser  at  that
          offset   exists.   The  counter  should  start  from  0  and  be
          incremented by 1 until the function returns non-zero.

   int raptor_serializer_syntax_name_check(const char *name)
          Check name is a known serializer syntax name.

URI CLASS

   Raptor has a raptor_uri class must be used for manipulating and passing
   URI references.  The default internal implementation uses char* strings
   for  URIs,  manipulating  them  and  constructing   them.    This   URI
   implementation   can  be  replaced  by  any  other  that  provides  the
   equivalent functionality, using the raptor_uri_set_handler function.

URI CONSTRUCTORS

   There a several constructors for raptor_uri to build  them  from  char*
   strings and existing raptor_uri objects.

   raptor_uri* raptor_new_uri(const unsigned char* uri_string)
          Create a raptor URI from a string URI-reference uri_string.

   raptor_uri*  raptor_new_uri_from_uri_local_name(raptor_uri*  uri, const
   unsigned char* local_name)
          Create a raptor  URI  from  a  string  URI-reference  local_name
          relative   to   an   existing   URI-reference.    This  performs
          concatenation of the local_name to the uri and not relative  URI
          resolution, which is done by the raptor_new_uri_relative_to_base
          constructor.

   raptor_uri* raptor_new_uri_relative_to_base(raptor_uri* base_uri, const
   unsigned char* uri_string)
          Create a raptor URI from a string URI-reference uri_string using
          relative URI resolution to the base_uri.

   raptor_uri* raptor_new_uri_from_id(raptor_uri* base_uri, const unsigned
   char* id)
          Create  a raptor URI from a string RDF ID id concatenated to the
          base_uri base URI.

   raptor_uri* raptor_new_uri_for_rdf_concept(const char* name)
          Create a raptor URI for the RDF namespace concept name.

   raptor_uri* raptor_new_uri_for_xmlbase(raptor_uri* old_uri))
          Create a raptor URI suitable for use with xml:base  (throw  away
          fragment)

URI DESTRUCTOR

   void raptor_free_uri(raptor_uri* uri)
          Destroy a raptor URI object.

URI METHODS

   int raptor_uri_equals(raptor_uri* uri1, raptor_uri* uri2)
          Return non-zero if the given URIs are equal.

   raptor_uri* raptor_uri_copy(raptor_uri* uri)
          Return a copy of the given raptor URI uri.

   unsigned  char*  raptor_uri_as_counted_string(raptor_uri  *uri, size_t*
   len_p)

   unsigned char* raptor_uri_as_string(raptor_uri* uri)
          Return a shared pointer to a string representation of the  given
          raptor  URI  uri.   This  string is shared and must not be freed
          (otherwise  see  the   raptor_uri_to_*   methods   below).    If
          raptor_uri_as_counted_string is used, the length of the returned
          string is stored in *len_p if not NULL.

   unsigned  char*  raptor_uri_to_counted_string(raptor_uri  *uri,  size_t
   *len_p)

   unsigned char* raptor_uri_to_string(raptor_uri *uri)
          Return  a  to a newly alloced string representation of the given
          raptor URI uri.  This string must be freed by the  caller  using
          raptor_free_memory.   If  raptor_uri_to_counted_string  is used,
          the length of the returned string is stored  in  *len_p  if  not
          NULL.

   unsigned   char*   raptor_uri_to_relative_counted_uri_string(raptor_uri
   *base_uri, raptor_uri *reference_uri, size_t *length_p)

   unsigned char* raptor_uri_to_relative_uri_string(raptor_uri  *base_uri,
   raptor_uri *reference_uri)
          Return  a new relative URI string of a URI reference_uri against
          a base URI base_uri.  The returned string  must  be  freed  with
          raptor_free_memory.  If raptor_uri_to_relative_counted_string is
          used, the length of the returned string is stored in  *len_p  if
          not NULL.

   void raptor_uri_print(const raptor_uri* uri, FILE *stream)
          Print URI uri to the file handle stream.

   int raptor_iostream_write_uri(raptor_iostream* iostr,  raptor_uri* uri)
          Write the raptor_uri uri to the iostream ostr.

URI UTILITY FUNCTIONS

   void  raptor_uri_resolve_uri_reference  (const unsigned char* base_uri,
   const unsigned  char*  reference_uri,  char  unsigned*  buffer,  size_t
   length)
          This  is  a  standalone  function that resolves the relative URI
          reference_uri against the base URI base_uri according to the URI
          resolution  rules  in  RFC2396.   The resulting URI is stored in
          buffer which is of length bytes.  If this is too small, no  work
          will be done.

   char *raptor_uri_filename_to_uri_string(const unsigned char* filename)
          This  is  a  standalone  function  that  turns  a local filename
          (Windows or Unix style as appropriate for platform) into  a  URI
          string (file).
           The  returned  string must be freed by the caller. Some systems
          require memory allocated in a library to be  deallocated  inside
          that library in which case raptor_free_memory may be used.

   char     *raptor_uri_uri_string_to_filename(const     unsigned    char*
   uri_string)

   char    *raptor_uri_uri_string_to_filename(const     unsigned     char*
   uri_string, unsigned char **fragment_p)
          These  are  standalone  functions  that  turn  a URI string that
          represents a  local  filename  (file:)  into  a  filename,  with
          optional  URI  fragment.  If fragment_p is not NULL it points to
          the location to store a newly allocated  string  containing  the
          fragment.   The  returned  strings  must be freed by the caller.
          Some systems  require  memory  allocated  in  a  library  to  be
          deallocated inside that library in which case raptor_free_memory
          may be used.

   int raptor_uri_is_file_uri(const unsigned char* uri_string)
          DEPRECATED in 1.4.9.  Returns non-zero if the given  URI  string
          represents a filename.  Use raptor_uri_uri_string_is_file_uri in
          preference.

   int raptor_uri_uri_string_is_file_uri(const unsigned char* uri_string)
          Returns non-zero if the given URI string represents a filename.

URI CLASS IMPLEMENTATION

   void  raptor_uri_set_handler(const  raptor_uri_handler  *handler,  void
   *context)
          Change the URI class implementation to the functions provided by
          the handler URI implementation.  The context user data is passed
          in to the handler URI implementation calls.

   void    raptor_uri_get_handler(raptor_uri_handler    **handler,    void
   **context)
          Return the current raptor URI class implementation  handler  and
          context

WWW CLASS

   This is a small wrapper class around existing WWW libraries in order to
   provide HTTP GET or  better  URI  retrieval  for  Raptor.   It  is  not
   intended to be a general purpose WWW retrieval interface.

WWW CLASS INITIALISATION AND CLEANUP

   void raptor_www_init(void)

   void raptor_www_finish(void)
          Initialise   or   terminate   the   raptor_www   infrastructure.
          raptor_www_init and raptor_finish are called by raptor_init  and
          raptor_finish respecitively, otherwise must be called once each.

   NOTE   Several  of  the  WWW  library implementations require once-only
          initialisation and termination functions to be  called,  however
          raptor  cannot determine whether this is already done before the
          library is  initialised  in  raptor_www_init  or  terminated  in
          raptor_www_finish,  so  always performs it.  This can be changed
          by raptor_www_no_www_library_init_finish.

   void raptor_www_no_www_library_init_finish(void)
          If this is called before raptor_www_init, it will not  call  the
          underlying WWW library global initialise or terminate functions.
          The application code must perform both operations.

          For example with curl, after this function  is  called,  neither
          curl_global_init  nor  curl_global_cleanup will be called during
          raptor_www_init or raptor_www_finish respectively.

WWW CONSTRUCTORS

   raptor_www *raptor_www_new(void)

   raptor_www *raptor_www_new_with_connection(void* connection)
          Create a  raptor  WWW  object  capable  of  URI  retrieval.   If
          connection  is given, it must match the connection object of the
          underlying WWW implementation.  At present,  this  is  only  for
          libcurl,  and  allows  you to re-use an existing curl handle, or
          use one which has been set up with some desired qualities.

WWW DESTRUCTOR

   void raptor_www_free(raptor_www *www)
          Destroy a raptor WWW object.

WWW METHODS

   void raptor_www_set_user_agent(raptor_www *www, const char *user_agent)
          Set the HTTP User-Agent header value.

   int  raptor_www_set_http_cache_control(raptor_www*  www,  const   char*
   cache_control)
          Set the HTTP Cache-Control header value.

   void raptor_www_set_proxy(raptor_www *www, const char *proxy)
          Set   the   HTTP   proxy   -   usually  a  string  of  the  form
          http://server:port

   raptor_www_set_write_bytes_handler(raptor_www                     *www,
   raptor_www_write_bytes_handler handler, void *user_data)
          Set  the  handler  to  receive  bytes  written by the raptor_www
          implementation.

   void        raptor_www_set_content_type_handler(raptor_www        *www,
   raptor_www_content_type_handler handler, void *user_data)
          Set  the handler to receive the HTTP Content-Type value, when/if
          discovered during retrieval by the raptor_www implementation.

   void raptor_www_set_http_accept(raptor_www *www, const char *value)
          Set the WWW HTTP Accept: header to value.  If value is NULL,  an
          empty header is sent.

   void            raptor_www_set_error_handler(raptor_www           *www,
   raptor_message_handler error_handler, void *error_data)
          Set the error handler routine for the  raptor_www  class.   This
          takes  the  same  arguments  as the raptor_parser error, warning
          handler methods.

   void raptor_www_set_uri_filter(raptor_www* www,  raptor_uri_filter_func
   filter, void* user_data)
          Set  the  URI  filter  function filter for URIs retrieved by the
          raptor_www object.

   void* raptor_www_get_connection(raptor_www *www)
          Return  the  underlying  WWW  library  connection  object.   For
          example, for libcurl this is the curl_handle.

   void raptor_www_set_connection_timeout(raptor_www* www, int timeout)
          Set the WWW connection timeout in seconds.

   raptor_uri* raptor_www_get_final_uri(raptor_www* www)
          Get  the  final  URI  from  a  WWW  retrieval, which may include
          redirections.

WWW ACTION METHODS

   int raptor_www_fetch(raptor_www *www, raptor_uri *uri)
          Retrieve the given URL, returning non zero on failure.

   int raptor_www_fetch_to_string(raptor_www *www, raptor_uri  *uri,  void
   **string_p, size_t *length_p, void *(*malloc_handler)(size_t size))
          Retrieve  the  given  URL to a string.  string_p must point to a
          void* pointer that will be used to  store  the  newly  allocated
          string.   length_p  if  not  NULL,  it will be used to store the
          length of the new string.

   void raptor_www_abort(raptor_www *www, const char *reason)
          Abort an ongoing raptor WWW operation. Typically used within one
          of the raptor WWW handlers.

QNAME CLASS

   This  is  a  class for handling XML QNames consisting of the pair of (a
   URI from a namespace, a local name) along with  an  optional  value  --
   useful    for    XML    attributes.     This    is    used   with   the
   raptor_namespace_stack and raptor_namespace classes to handle  a  stack
   of raptor_namespace that build on raptor_qname.

QNAME CONSTRUCTORS

   There  are  two  constructors  for  raptor_qname  to  build qnames with
   optional values on a stack of names.

   raptor_qname*  raptor_new_qname(raptor_namespace_stack  *nstack,  const
   unsigned     char     *name,     const     unsigned     char    *value,
   raptor_simple_message_handler error_handler, void *error_data)
          Create a raptor QName name (a possibly  :-separated  name)  with
          name  to  be  resolved against the given nstack namespace stack.
          An optional value can be given, and if there is  an  error,  the
          error_handler   and  error_data  will  be  used  to  invoke  the
          callback.

   raptor_qname*                raptor_new_qname_from_namespace_local_name
   (raptor_namespace  *ns, const unsigned char *local_name, const unsigned
   char *value)
          Create  a  raptor  QName  using  the  namespace  name   of   the
          raptor_namespace  ns  and  the local name local_name, along with
          optional value value.   Errors  are  reported  using  the  error
          handling and data of the namespace.

   raptor_qname* raptor_qname_copy(raptor_qname *qname)
          Create  a  raptor  QName from an existing one, returning NULL on
          failure.

QNAME DESTRUCTOR

   void raptor_free_qname(raptor_qname* name)
          Destroy a raptor qname object.

QNAME METHODS

   int raptor_qname_equal(raptor_qname* name1, raptor_qname *name2)
          Return non-zero if the given QNames are equal.

   int  raptor_iostream_write_qname(raptor_iostream*  iostr,  raptor_qname
   *qname)
          Write the raptor_qname qname to the iostream ostr.

   const unsigned char* raptor_qname_get_local_name(raptor_qname* name)
          Get the local name of the QName.

   const unsigned char* raptor_qname_get_value(raptor_qname* name)
          Get the value of the QName for an XML attribute QName.

   const unsigned char* raptor_qname_get_counted_value(raptor_qname* name,
   size_t* length_p)
          Get the value fo the QName along with the length (if length_p is
          not NULL) for an XML attribute QName.

   unsigned    char*   raptor_qname_to_counted_name(raptor_qname*   qname,
   size_t* length_p)
          Get the formatted QName as a newly allocated counted string  (if
          length_p is not NULL).

QNAME UTILITY FUNCTIONS

   raptor_uri*  raptor_qname_string_to_uri(raptor_namespace_stack *nstack,
   const      unsigned      char       *name,       size_t       name_len,
   raptor_simple_message_handler error_handler, void *error_data)
          Return  the  URI corresponding to the QName according to the RDF
          method; concatenating the namespace's name (URI) with the  local
          name.  Takes the same arguments as raptor_new_qname but does not
          create a raptor_qname object.

   raptor_namespace* raptor_qname_get_namespace(raptor_qname* name)
          Return the raptor_namespace used by the QName.   Will  never  be
          NULL even for the default namespace in which case the URI of the
          returned namespace object will be NULL.

NAMESPACE CLASS

   An XML namespace class - each entry is on a stack  and  consists  of  a
   name  (URI)  and  prefix.   The  prefix or the name but not both may be
   empty.  If the prefix is empty, it defines the default prefix.  If  the
   name is empty, it undefines the given prefix.

NAMESPACE CONSTRUCTORS

   raptor_namespace*  raptor_new_namespace(raptor_namespace_stack *nstack,
   const unsigned char *prefix, const unsigned  char  *ns_uri_string,  int
   depth)

   raptor_namespace*  raptor_new_namespace_from_uri(raptor_namespace_stack
   *nstack, const unsigned char *prefix, raptor_uri* ns_uri, int depth)
          Create a new raptor_namespace  object  on  the  given  namespace
          stack  nstack  with prefix prefix and namespace name either from
          URI string ns_uri_string or from copying URI ns_uri.

   If prefix is NULL, it defines the URI for the default namespace prefix.
   If  the  namespace name (ns_uri_string or ns_uri) is NULL, it undefines
   the given prefix in the current scope.  Both prefix and URI may be NULL
   to undefine the default namespace.  depth signifies the position of the
   namespace on the stack; 0 is the bottom of the stack and generally  the
   first depth for user namespace declarations.

   Namespaces declared on the same depth (such as on the same XML element,
   typically) can be handily  freed  with  raptor_namespaces_end_for_depth
   method on the namespace stack class.

NAMESPACE DESTRUCTOR

   void raptor_free_namespace(raptor_namespace *ns)
          Destroy a raptor namespace object.

NAMESPACE METHODS

   raptor_uri* raptor_namespace_get_uri(const raptor_namespace *ns)
          Return the namespace name (URI) of the namespace.

   const unsigned char* raptor_namespace_get_prefix(const raptor_namespace
   *ns)
          Return the prefix of the namespace.

   const    unsigned    char*    raptor_namespace_get_counted_prefix(const
   raptor_namespace* ns, size_t* length_p)
          Return  the  prefix  of  the namespace as a string with optional
          count stored in the variable address length_p if it is not NULL.

   unsigned  char  *raptor_namespaces_format(const  raptor_namespace  *ns,
   size_t *length_p)
          Format  the namespace as a string and return it as a new string,
          returning the length of the resulting string in length_p  if  it
          is  not NULL.  The string format is suitable for emitting in XML
          to declare the namespace.

   int       raptor_iostream_write_namespace(raptor_iostream*       iostr,
   raptor_namespace *ns)
          Write  a  formatted  namespace  declaration  like xmlns... to an
          iostream iostr.

NAMESPACE UTILITY FUNCTIONS

   int        raptor_namespace_copy(raptor_namespace_stack        *nstack,
   raptor_namespace *ns, int new_depth)
          Copy the namespace from the current stack to the new one, nstack
          at depth new_depth.

   int   raptor_new_namespace_parts_from_string(unsigned   char   *string,
   unsigned char **prefix, unsigned char **uri_string)
          Parse  string  with  an  XML-style  namespace  declaration  like
          xmlns="",  xmlns="uri",  xmlns:prefix=""  or  xmlns:prefix="uri"
          into  the  strings pointed to by prefix string and a uri_string.
          Empty  prefixes  or  namespace  names  return   NULL   pointers.
          Returned   strings   must   be   freed   by   the  caller  using
          raptor_free_memory.

NAMESPACE STACK CLASS

   A stack of raptor_namespace objects where the namespaces on top of  the
   stack   have   wider  scope  and  override  earlier  (lower)  namespace
   declarations.  Intended to match the XML namespace declaring  semantics
   using xmlns attributes.

NAMESPACE STACK CONSTRUCTORS

   raptor_namespace_stack*        raptor_new_namespaces(raptor_uri_handler
   *uri_handler,    void    *uri_context,    raptor_simple_message_handler
   error_handler, void *error_data, int defaults)

   int        raptor_namespaces_init(raptor_namespace_stack       *nstack,
   raptor_uri_handler          *handler,          void           *context,
   raptor_simple_message_handler   error_handler,  void  *error_data,  int
   defaults)
          Create or initialise a new  raptor_namespace_stack  object  with
          the   given   URI  and  error  handlers.   raptor_namespaces_new
          allocates   new   memory   for   the   namespace    stack    and
          raptor_namespaces_init  initialises an existing declared nstack,
          which   could    be    statically    allocated.     Note    that
          raptor_uri_get_handler  can  be  useful  to  return  the current
          raptor URI handler/context.   The  defaults  argument  describes
          which  default  namespaces  are declared in the empty stack.  At
          present, 0 is none, 1 for just the XML namespace and 2 is for  a
          typical  set of namespaces used for RDF, RDFS, Dublin Core, OWL,
          ...  that may vary over time.

          In versions 1.4.16 or newer  this  returns  an  integer  result,
          non-0 on failure.

NAMESPACE STACK DESTRUCTORS

   void raptor_free_namespaces(raptor_namespace_stack *nstack)
          Destroy  a namespace stack object, freeing the nstack (goes with
          raptor_new_namespaces).

   void raptor_namespaces_clear(raptor_namespace_stack *nstack)
          Clear a statically allocated namespace stack; does not free  the
          nstack.  (goes with raptor_namespaces_init).

NAMESPACE STACK METHODS

   void  raptor_namespaces_start_namespace(raptor_namespace_stack *nstack,
   raptor_namespace *nspace)
          Start the given nspace  on  the  stack,  at  the  depth  already
          defined.

   int       raptor_namespaces_start_namespace_full(raptor_namespace_stack
   *nstack, const unsigned char *prefix, const unsigned char *nspace,  int
   depth)
          Create  a  new  raptor_namespace and start it on the stack.  See
          raptor_new_namespace for the meaning of the argumens.

   void  raptor_namespaces_end_for_depth(raptor_namespace_stack   *nstack,
   int depth)
          End (and free) all namespaces on the stack at the given depth.

   raptor_namespace*               raptor_namespaces_get_default_namespace
   (raptor_namespace_stack *nstack)
          Return the current default  raptor_namespace  of  the  namespace
          stack or NULL if there is none.

   raptor_namespace*
   raptor_namespaces_find_namespace_by_uri(raptor_namespace_stack *nstack,
   raptor_uri *ns_uri)
          Find  the first namespace on the stack with the given uri ns_uri
          or NULL if there is none.

   raptor_namespace
   *raptor_namespaces_find_namespace_by_uri(raptor_namespace_stack
   *nstack, const unsigned char *prefix, int prefix_length)
          Find the first namespace on the stack with the  given  namespace
          prefix or NULL if there is none.

   int         raptor_namespaces_namespace_in_scope(raptor_namespace_stack
   *nstack, const raptor_namespace *nspace)
          Return non-zero if the raptor_namespace nspace  is  declared  on
          the stack; i.e. in scope if this is a stack of XML namespaces.

NAMESPACE STACK UTILITY FUNCTIONS

   raptor_qname*  raptor_namespaces_qname_from_uri(raptor_namespace_stack*
   nstack,  raptor_uri* uri, int xml_version)
          Create a raptor QName from the URI uri if the URI is  squal  one
          of  the  namespace  URIs  on  the  namespace  stack  nstack URIs
          concatenated to a legal XML name  for  the  given  XML  version.
          URIs  are  created  and  errors are reported using the namespace
          stack fields.  Fails if it cannot be legally described with  any
          of the namespaces.

SEQUENCE CLASS

   A  class  for  ordered  sequences of items, adding at either end of the
   sequence.  The method names should be familiar to Perl users.

SEQUENCE CONSTRUCTOR

   raptor_sequence*      raptor_new_sequence(raptor_sequence_free_handler*
   free_handler, raptor_sequence_print_handler* print_handler)
          Create  a  new empty sequence, with optional handler for freeing
          elements (as  used  by  raptor_free_sequence  and  printing  out
          elements (used by raptor_sequence_print).

SEQUENCE DESTRUCTOR

   void raptor_free_sequence(raptor_sequence* seq)
          Destoy  a sequence object, freeing any items if the free handler
          was defined in the constructor.

SEQUENCE METHODS

   int raptor_sequence_size(raptor_sequence* seq)
          Return the number of items in the sequence.

   int raptor_sequence_set_at(raptor_sequence* seq, int idx, void *data)
          Set the sequence item at index idx to the value data,  extending
          it if necessary.

   int raptor_sequence_push(raptor_sequence* seq, void *data)
          Add item data to the end of the sequence.

   int raptor_sequence_shift(raptor_sequence* seq, void *data)
          Add item data to the start of the sequence.

   void* raptor_sequence_get_at(raptor_sequence* seq, int idx)
          Get  the  sequence  item  at  index idx or NULL if no such index
          exists.

   void* raptor_sequence_pop(raptor_sequence* seq)
          Remove and return an item from the end of the sequence, or  NULL
          if is empty.

   void* raptor_sequence_unshift(raptor_sequence* seq)
          Remove  and  return  an  item from the start of the sequence, or
          NULL if is empty.

   void  raptor_sequence_sort(raptor_sequence*  seq,   int(*compare)(const
   void *, const void *))
          Sort  the  sequence  using the given comparison function compare
          which is passed to qsort(3) internally.

   int raptor_compare_strings(const void *a, const void *b)
          Helper function useful with raptor_sequence_sort.

   void      raptor_sequence_set_print_handler(raptor_sequence       *seq,
   raptor_sequence_print_handler *print_handler)
          Set  the  print  handler  for  the  sequence,  an alternative to
          setting it in the constructor.

   void raptor_sequence_print_string(char *data, FILE *fh)
          Helper print handler function useful for printing out  sequences
          of strings.

   void raptor_sequence_print_uri(char *data, FILE *fh)
          Helper  print handler function useful for printing out sequences
          of raptor_uri* objects.

   void raptor_sequence_print(raptor_sequence* seq, FILE* fh)
          Print out the sequence in a  debug  format  to  the  given  file
          handler  fh.  NOTE: The exact format is not guaranteed to remain
          the same between releases.

   int raptor_sequence_join(raptor_sequence* dest, raptor_sequence *src)
          Join two sequences moving all items from sequence src to the end
          of  sequence  dest.   After this operation, sequence src will be
          empty (zero size) but  will  have  the  same  item  capacity  as
          before.

   void* raptor_sequence_delete_at(raptor_sequence* seq, int idx)
          Remove an item from position idx in the sequence, returning it.

STRINGBUFFER CLASS

   A class for growing strings, small chunks at a time.

STRINGBUFFER CONSTRUCTOR

   raptor_stringbuffer* raptor_new_stringbuffer(void)
          Create a new stringbuffer.

STRINGBUFFER DESTRUCTOR

   void raptor_free_stringbuffer(raptor_stringbuffer* stringbuffer)
          Destroy a stringbuffer.

STRINGBUFFER METHODS

   int      raptor_stringbuffer_append_counted_string(raptor_stringbuffer*
   stringbuffer, const unsigned char *string, size_t length, int do_copy)
          Append a string of length bytes to a  stringbuffer,  copying  it
          only if do_copy is non-0.

   int              raptor_stringbuffer_append_string(raptor_stringbuffer*
   stringbuffer, const unsigned char* string, int do_copy)
          Append a string to a stringbuffer, copying it only if do_copy is
          non-0.

   int             raptor_stringbuffer_append_decimal(raptor_stringbuffer*
   stringbuffer, int integer)
          Append a formatted decimal integer to a stringbuffer.

   int        raptor_stringbuffer_append_stringbuffer(raptor_stringbuffer*
   stringbuffer, raptor_stringbuffer* append)
          Append  a  stringbuffer  append  to  a stringbuffer.  The append
          stringbuffer is emptied but not destroyed.

   int     raptor_stringbuffer_prepend_counted_string(raptor_stringbuffer*
   stringbuffer, const unsigned char* string, size_t length, int do_copy)
          Prepend a string of length bytes to the start of a stringbuffer,
          copying it only if do_copy is non-0.

   int             raptor_stringbuffer_prepend_string(raptor_stringbuffer*
   stringbuffer, const unsigned char* string, int do_copy)
          Prepend a string to the start of a stringbuffer, copying it only
          if do_copy is non-0.

   unsigned  char   *   raptor_stringbuffer_as_string(raptor_stringbuffer*
   stringbuffer)
          Return  the  stringbuffer  as  a  single  string.  The string is
          shared and should be copied if needed.

   size_t raptor_stringbuffer_length(raptor_stringbuffer* stringbuffer)
          Return the length of the stringbuffer.

   int             raptor_stringbuffer_copy_to_string(raptor_stringbuffer*
   stringbuffer, unsigned char *string, size_t length)
          Copy the stringbuffer into a single string buffer string of size
          length.  Returns non-0 on failure.

IOSTREAM CLASS

   This class provides an I/O stream that can write to  filenames,  FILE*,
   strings and user-defined output via callbacks.

IOSTREAM CONSTRUCTOR

   raptor_iostream* raptor_new_iostream_from_handler2(void* context, const
   raptor_iostream_handler2 *handler)
          Create a new raptor read or write iostream from  a  user-defined
          raptor_iostream_handler2 handler that is called with the passed-
          in context for the write operations.

   raptor_iostream* raptor_new_iostream_from_handler(void* context,  const
   raptor_iostream_handler *handler)
          DEPRECATED  in  1.4.17 - use raptor_new_iostream_from_handler2()
          with the new handler format.  Create a new raptor read  iostream
          from  a  user-defined  raptor_iostream_handler  handler  that is
          called with the passed-in context for the write operations.

   raptor_iostream* raptor_new_iostream_to_sink(void)
          Create a new raptor write iostream  that  discards  all  written
          output.

   raptor_iostream* raptor_new_iostream_to_filename(const char *filename)
          Create  a new raptor write iostream that creates and writes to a
          new file filename.

   raptor_iostream* raptor_new_iostream_to_file_handle(FILE *handle)
          Create a new raptor write iostream that creates and writes to an
          existing, already opened, C Standard I/O handle FILE* handle.

   raptor_iostream*  raptor_new_iostream_to_string(void **string_p, size_t
   *length_p, void *(*malloc_handler)(size_t size))
          Create a new raptor write iostream which creates  a  new  string
          once  raptor_free_iostream is called.  The new string pointer is
          written in string, the length in length_p (if not NULL) and  the
          memory  allocation is made using the malloc_handler, or if NULL,
          raptor's default memory allocator.

   raptor_iostream* raptor_new_iostream_from_sink(void)
          Create a new raptor read iostream that is  immediately  finished
          and returns end of file.

   raptor_iostream*      raptor_new_iostream_from_filename(const      char
   *filename)
          Create  a  new  raptor  read  iostream  from  an  existing  file
          filename.

   raptor_iostream* raptor_new_iostream_from_file_handle(FILE *handle)
          Create  a  new  raptor  read  iostream from an already opened, C
          Standard I/O handle FILE* handler.

   raptor_iostream* raptor_new_iostream_from_string(void  *string,  size_t
   length)
          Create  a  new  raptor  read  iostream  reading from an existing
          string of length bytes.

IOSTREAM DESTRUCTOR

   void raptor_free_iostream(raptor_iostream *iostr)
          Destroy a Raptor iostream object.

IOSTREAM METHODS

   int  raptor_iostream_write_bytes(raptor_iostream  *iostr,  const   void
   *ptr, size_t size, size_t nmemb)
          Write  a  counted  set of elements to an iostream. Inmemb is the
          count of elements of size size, starting at memory ptr.  Similar
          to fwrite(3) and write(2).

   int raptor_iostream_write_byte(raptor_iostream *iostr, const int byte)
          Write a single byte an iostream.  Similar to fputc(3).

   void raptor_iostream_write_end(raptor_iostream *iostr)
          Finish writing to an iostream.

   int  raptor_iostream_write_string(raptor_iostream  *iostr,  const  void
   *string)
          Write a  NUL-terminated  string  to  an  iostream.   Similar  to
          fputs(3).

   int  raptor_iostream_write_counted_string(raptor_iostream *iostr, const
   void *string, size_t len)
          Write a string of length len to an iostream.

   unsigned long raptor_iostream_tell(raptor_iostream *iostr)
          Return the byte offset into the iostream.

   size_t raptor_iostream_get_bytes_written_count(raptor_iostream *iostr)
          DEPRECATED in 1.4.17  for  raptor_iostream_tell().   Return  the
          number of bytes written so far to the iostream.

   int raptor_iostream_write_decimal(raptor_iostream *iostr, int integer)
          Write a decimal formatted integer integer to the iostream.

   int raptor_iostream_format_hexadecimal(raptor_iostream *iostr, unsigned
   int integer, int width)
          Write a hexadecimal formatted unsigned integer to the  iostream,
          left-padded with '0's to width columns.

   int      raptor_iostream_write_stringbuffer(raptor_iostream*     iostr,
   raptor_stringbuffer *sb)
          Write the stringbuffer to an iostream iostr.

   int  raptor_iostream_read_bytes(raptor_iostream*  iostr,   void   *ptr,
   size_t size, size_t nmemb)
          Read  bytes  from  the  iostream  into  buffer  ptr  up to nmemb
          elements of size size.

   int raptor_iostream_read_eof(raptor_iostream *iostr)
          Return non-0 if the iostream is finished.

XML SAX2 READER CLASS

   This class provides the functionality  to  generate  SAX2  events  from
   parsing XML content, including XML namespace support.

XML SAX2 CONSTRUCTOR

   raptor_sax2*  raptor_new_sax2(void  *user_data,  raptor_error_handlers*
   error_handlers)
          Create a new SAX2  XML  reader  with  the  given  error  handler
          object.

XML WRITER DESTRUCTOR

   void raptor_free_sax2(raptor_sax2 *sax2)
          Destroy a SAX2 XML reader object.

SAX2 SET HANDLER METHODS

   void      raptor_sax2_set_start_element_handler(raptor_sax2      *sax2,
   raptor_sax2_start_element_handler handler)
          Set the SAX2 start element handler.

   void       raptor_sax2_set_end_element_handler(raptor_sax2       *sax2,
   raptor_sax2_end_element_handler handler)
          Set the SAX2 end element handler.

   void        raptor_sax2_set_characters_handler(raptor_sax2       *sax2,
   raptor_sax2_characters_handler handler)
          Set the SAX2 character data element handler.

   void          raptor_sax2_set_cdata_handler(raptor_sax2          *sax2,
   raptor_sax2_cdata_handler handler)
          Set the SAX2 CDATA section element handler.

   void         raptor_sax2_set_comment_handler(raptor_sax2         *sax2,
   raptor_sax2_comment_handler handler)
          Set the SAX2 XML comment handler.

   void  raptor_sax2_set_unparsed_entity_decl_handler(raptor_sax2   *sax2,
   raptor_sax2_unparsed_entity_decl_handler handler)
          Set the SAX2 XML unparsed entity declaration handler.

   void   raptor_sax2_set_external_entity_ref_handler(raptor_sax2   *sax2,
   raptor_sax2_external_entity_ref_handler handler)
          Set the SAX2 XML external entity reference handler.

   void        raptor_sax2_set_namespace_handler(raptor_sax2        *sax2,
   raptor_namespace_handler handler)
          Set  the  SAX2  XML  namespace  declaration  handler when an XML
          namespace is declared.

SAX2 PARSING METHODS

   void raptor_sax2_parse_start(raptor_sax2 *sax2, raptor_uri *base_uri)
          Start a SAX2 parse of XML content with the base URI uri.

   int  raptor_sax2_parse_chunk(raptor_sax2  *sax2,  const  unsigned  char
   *buffer, size_t len, int is_end)
          Parse  the  XML  content  in  buffer  of size len returning SAX2
          events via handlers.  If is_end is non-zero,  it  indicates  the
          end  of  the  parsing.   This  method  can  only be called after
          raptor_sax2_parse_start().

SAX2 SCOPE METHODS

   const   unsigned   char*   raptor_sax2_inscope_xml_language(raptor_sax2
   *sax2)
          Get the current in-scope XML language (xml:lang) value.

   raptor_uri* raptor_sax2_inscope_base_uri(raptor_sax2 *sax2)
          Get  the  current  in-scope  Base  URI  (xml:base or document or
          protocol) value.

XML ELEMENT CLASS

   This class provides an XML element that can be used with the XML Writer
   Class to generate XML documents.

XML ELEMENT CONSTRUCTORS

   raptor_xml_element*  raptor_new_xml_element(raptor_qname*  name,  const
   unsigned char* xml_language, raptor_uri* xml_base)
          Create a new XML element with  the  element  name  name  in  the
          context of xml:lang xml_language and base URI xml_base.

   raptor_xml_element*
   raptor_new_xml_element_from_namespace_local_name(raptor_namespace  *ns,
   const   unsigned   char   *name,  const  unsigned  char*  xml_language,
   raptor_uri* xml_base
          Create a new XML element based on the given  XML  namespace  and
          localname  in  the context of xml:lang xml_language and base URI
          xml_base.

XML ELEMENT DESTRUCTOR

   void raptor_free_xml_element(raptor_xml_element *element)
          Destroy a XML element object.

XML ELEMENT METHODS

   raptor_qname*           raptor_xml_element_get_name(raptor_xml_element*
   xml_element)
          Get the XML element QName of XML element xml_element.

   void raptor_xml_element_set_attributes(raptor_xml_element* xml_element,
   raptor_qname **attributes, int count)
          Set the attributes on XML element xml_element to  the  array  of
          QNames in array attributes of size count.

   raptor_qname**    raptor_xml_element_get_attributes(raptor_xml_element*
   xml_element)
          Get the attributes of an XML element xml_element as an array  of
          QNames.  As set by void raptor_xml_element_set_attributes.

   int         raptor_xml_element_get_attributes_count(raptor_xml_element*
   xml_element)
          Get the number of attributes of an XML  element  xml_element  as
          set by void raptor_xml_element_set_attributes.

   int            raptor_xml_element_declare_namespace(raptor_xml_element*
   xml_element, raptor_namespace* nspace)
          Declare an XML  namespace  nspace  expliclitly  on  XML  element
          xml_element.   Namespaces used in the element or attribute names
          are automatically declared, this method allows  additional  ones
          to be done.

   int raptor_xml_element_is_empty(raptor_xml_element* xml_element)
          Return non-0 if the XML element is empty.

   int      raptor_iostream_write_xml_element(raptor_iostream*      iostr,
   raptor_xml_element  *element,   raptor_namespace_stack*   nstack,   int
   is_empty,   int  is_end,  raptor_simple_message_handler  error_handler,
   void* error_data, int depth)
          Write a XML element xml_element to iostream ostr.  This is  done
          in  context  of an XML namespace stack nstack and at depth depth
          in the stack (see Namespace class constructors).

          The element may be an empty element if is_empty is  non-zero  or
          may  be  a  close element if is_end is non-zero (else is a start
          element).  The error_handler method along with error_data  allow
          error reporting to be given.

   const                           unsigned                          char*
   raptor_xml_element_get_language(raptor_xml_element* xml_element)
          Get the xml:lang language of the XML element.

XML WRITER CLASS

   This class provides the functionality to generate simple XML  documents
   consisting  of  elements  with attributes, character data and comments.
   The documents can be written to an iostream.

XML WRITER CONSTRUCTOR

   raptor_xml_writer*        raptor_new_xml_writer(raptor_namespace_stack*
   nstack,    raptor_uri_handler*    uri_handler,    void*    uri_context,
   raptor_iostream*  iostr,  raptor_simple_message_handler  error_handler,
   void *error_data, int canonicalize)
          Create  a  new  XML  Writer  writing  to  iostream  iostr.   The
          error_handler method along with error_data allow error reporting
          to be given.  nstack is either an existing namespace stack to be
          used or if NULL, a new one with only the XML  namespace  defined
          is  created.   Note that raptor_uri_get_handler can be useful to
          return the current raptor URI handler/context.  canonicalize  is
          currently  unused  and  should  be  set  to 1 but may allow non-
          canonical XML writing to be allowed in future.

XML WRITER DESTRUCTOR

   void raptor_free_xml_writer(raptor_xml_writer* xml_writer)
          Destroy a XML Writer object.

XML WRITER METHODS

   void   raptor_xml_writer_empty_element(raptor_xml_writer*   xml_writer,
   raptor_xml_element *element)
          Write  XML  element  element  as  an  empty  element (no element
          content) to the XML Writer xml_writer.

   void   raptor_xml_writer_start_element(raptor_xml_writer*   xml_writer,
   raptor_xml_element *element)
          Write  a  start  element  along with an attributes and namespace
          declarations  for  XML  element  element  to  the   XML   Writer
          xml_writer.

   void    raptor_xml_writer_end_element(raptor_xml_writer*    xml_writer,
   raptor_xml_element *element)
          Write an end element form for XML element  element  to  the  XML
          Writer xml_writer.

   void   raptor_xml_writer_cdata(raptor_xml_writer*   xml_writer,   const
   unsigned char *str)
          Write XML character data in str to the  XML  Writer  xml_writer.
          The characters in str will be XML escaped.

   void   raptor_xml_writer_cdata_counted(raptor_xml_writer*   xml_writer,
   const unsigned char* str, unsigned int length)
          Write XML character data in str of  length  length  to  the  XML
          Writer xml_writer.  The characters in str will be XML escaped.

   void    raptor_xml_writer_raw(raptor_xml_writer*    xml_writer,   const
   unsigned char* str)
          Write character data in str length to the XML Writer  xml_writer
          without XML escaping.

   void raptor_xml_writer_raw_counted(raptor_xml_writer* xml_writer, const
   unsigned char* str, unsigned int length)
          Write character data in str of length length to the  XML  Writer
          xml_writer without XML escaping.

   void   raptor_xml_writer_comment(raptor_xml_writer*  xml_writer,  const
   unsigned char* str)
          Write an XML comment in str to the XML Writer xml_writer.

   void  raptor_xml_writer_comment_counted(raptor_xml_writer*  xml_writer,
   const unsigned char* str, unsigned int length)
          Write  an  XML comment in str of length length to the XML Writer
          xml_writer.

   int raptor_xml_writer_features_enumerate(const raptor_feature  feature,
   const char **name, raptor_uri **uri, const char **label)
          Return  the  name,  URI,  string label (all optional) for an XML
          write feature, returning non-zero if no such feature exists.

   Raptor  features  have  URIs  that  are  constructed   from   the   URI
   http://feature.librdf.org/raptor-  and  the name so for example feature
   scanForRDF has URI http://feature.librdf.org/raptor-scanForRDF

   int    raptor_xml_writer_set_feature(raptor_xml_writer*     xml_writer,
   raptor_feature feature, int value)
          Set  an  XML  writer  feature  feature  to  a  particular value.
          Returns non 0 on failure or if  the  feature  is  unknown.   The
          current defined writer features are:
            Feature                                 Values
            RAPTOR_FEATURE_WRITER_AUTO_INDENT       Boolean (non 0 true)
            RAPTOR_FEATURE_WRITER_AUTO_EMPTY        Boolean (non 0 true)
            RAPTOR_FEATURE_WRITER_INDENT_WIDTH      Integer
            RAPTOR_FEATURE_WRITER_XML_DECLARATION   Boolean (non 0 true)

   If the writer_auto_indent feature is set (default true), the XML writer
   will automatically indent the output.

   If the writer_auto_empty feature is set (default true), the XML  writer
   will  automatically  generate  empty  elements  if  a start/end element
   sequence has no content.

   If the writer_indent_width feature is set (default 2) if the XML writer
   is outputing indented XML, it will use that many spaces.

   If  the  writer_xml_declaration  feature  is set (default true) the XML
   declaration is written at the start of serialized XML.

   int raptor_xml_writer_set_feature_string(raptor_xml_writer *xml_writer,
   raptor_feature feature, const unsigned char *value)
          Set  an XML writer feature feature to a particular string value.
          Returns non 0 on failure or if  the  feature  is  unknown.   The
          current    defined    XML   writer   features   are   given   in
          raptor_xml_writer_set_feature and at present only  take  integer
          values.  If  an integer value feature is set with this function,
          value is interpreted as an integer and then that value is used.

   int    raptor_xml_writer_get_feature(raptor_xml_writer*     xml_writer,
   raptor_feature feature)
          Get  XML  writer  feature  integer  values.  The allowed feature
          values       and       types       are        given        under
          raptor_xml_writer_features_enumerate.

   const                           unsigned                           char
   *raptor_xml_writer_get_feature_string(raptor_xml_writer*    xml_writer,
   raptor_feature feature)
          Get XML writer feature string values. The allowed feature values
          and types are given under raptor_xml_writer_features_enumerate.

   int raptor_xml_writer_get_depth(raptor_xml_writer* xml_writer)
          Get the current XML writer element stack depth.

   void raptor_xml_writer_flush(raptor_xml_writer* xml_writer)
          Flush the XML writer output for any pending writes.

   void raptor_xml_writer_newline(raptor_xml_writer* xml_writer)
          Write a newline to the XML writer (which may  trigger  indenting
          before the next item).

WORLD CLASS

   This  class stores the library state and configuration.  It will be the
   main class for initialsiing and configuring the library in Raptor 2.0.

WORLD CLASS CONSTRUCTOR

   raptor_world* raptor_new_world(void)
          Create a new raptor library object.

WORLD CLASS DESTRUCTOR

   void raptor_free_world(raptor_world* world)
          Destroy a raptor library object and free all resources.

WORLD CLASS METHODS

   int raptor_world_open(raptor_world* world)
          Start using a raptor library - allocate any dependent resources.
          This is optional.

   void raptor_world_set_libxslt_security_preferences(raptor_world *world,
   void *security_preferences)
          See raptor_set_libxslt_security_preferences() description.

   void raptor_world_set_libxml_flags(raptor_world *world,  int flags)
          See raptor_set_libxml_flags() description.

API CHANGES

   1.4.21
   No changes.

   1.4.20
   No changes.

   1.4.19
   Added raptor_world  class  to  prepare  for  V2  API  with  constructor
   raptor_new_world(),    destructor   raptor_free_world()   and   methods
   raptor_world_open(),    raptor_world_set_libxslt_security_preferences()
   and raptor_world_set_libxml_flags().

   The  raptor_identifier,  raptor_error_handlers  structs  both  gained a
   raptor_world* pointer field.

   Added           raptor_set_libxslt_security_preferences()           and
   raptor_set_libxml_flags().

   Added       raptor_libxml_flags       enum      for      flags      for
   raptor_world_set_libxml_flags() and raptor_set_libxml_flags().

   Added RAPTOR_FEATURE_PREFIX_ELEMENTS

   1.4.18
   Added atom serializer

   Added rdfa parser

   Added    serializer     features     RAPTOR_FEATURE_RSS_TRIPLES     and
   RAPTOR_FEATURE_ATOM_ENTRY_URI

   Added raptor_qname_to_counted_name()

   Added raptor_serialize_start_to_iostream()

   Added raptor_sequence_delete_at()

   Added raptor_xml_writer_newline()

   Added raptor_xml_writer_flush()

   Added raptor_xml_writer_get_depth()

   1.4.17
   Added   SAX2   class   raptor_sax2.    Added  new  SAX2  API  typedefs:
   raptor_sax2_start_element_handler,     raptor_sax2_end_element_handler,
   raptor_sax2_characters_handler,              raptor_sax2_cdata_handler,
   raptor_sax2_comment_handler,   raptor_sax2_unparsed_entity_decl_handler
   and   raptor_sax2_external_entity_ref_handler.    Added  new  SAX2  API
   functions:            raptor_new_sax2(),            raptor_free_sax2(),
   raptor_sax2_set_start_element_handler(),
   raptor_sax2_set_end_element_handler(),
   raptor_sax2_set_characters_handler(),  raptor_sax2_set_cdata_handler(),
   raptor_sax2_set_comment_handler(),
   raptor_sax2_set_unparsed_entity_decl_handler(),
   raptor_sax2_set_external_entity_ref_handler(),
   raptor_sax2_set_namespace_handler(),         raptor_sax2_parse_start(),
   raptor_sax2_parse_chunk(),    raptor_sax2_inscope_xml_language()    and
   raptor_sax2_inscope_base_uri()

   Added              features              RAPTOR_FEATURE_WRITE_BASE_URI,
   RAPTOR_FEATURE_WWW_HTTP_CACHE_CONTROL,
   RAPTOR_FEATURE_WWW_HTTP_USER_AGENT,   RAPTOR_FEATURE_JSON_CALLBACK  and
   RAPTOR_FEATURE_JSON_EXTRA_DATA

   Added raptor_handler_closure structure for error handlers.

   Added raptor_statement_compare()

   Added     raptor_iostream_write_string_python()     and      deprecated
   raptor_iostream_write_string_turtle()

   raptor_uri_set_handler(),                     raptor_uri_get_handler(),
   raptor_new_namespaces(),          raptor_namespaces_init()          and
   raptor_new_xml_writer() now take const handler pointers.

   Added raptor_www_set_http_cache_control()

   Added     QName     class    methods:    raptor_qname_get_local_name(),
   raptor_qname_get_value() and raptor_qname_get_counted_value()

   Added        raptor_iostream        read        handler        typedefs
   raptor_iostream_read_bytes_func,    raptor_iostream_read_eof_func   and
   added  new  structure  raptor_iostream_handler2  replacing   deprecated
   raptor_iostream_handler.

   Added    raptor_new_iostream_from_handler2()    replacing    deprecated
   raptor_new_iostream_from_handler()

   Added                                  raptor_new_iostream_from_sink(),
   raptor_new_iostream_from_filename(),
   raptor_new_iostream_from_file_handle()                              and
   raptor_new_iostream_from_string().

   Added                  raptor_iostream_tell                 deprecating
   raptor_iostream_get_bytes_written_count().

   Added raptor_iostream_read_bytes() and raptor_iostream_read_eof().

   Added raptor_xml_element_get_language().

   Added new enum raptor_log_level.

   Added   new   typedef   raptor_error_handlers.    and   new    function
   raptor_error_handlers_init().

   1.4.16
   raptor_namespaces_init() now returns an integer status

   Added raptor_new_xml_element_from_namespace_local_name()

   Added raptor_uri_compare().

   Added      new      features      for      the      'grddl'     parser:
   RAPTOR_FEATURE_HTML_TAG_SOUP,      RAPTOR_FEATURE_MICROFORMATS      and
   RAPTOR_FEATURE_HTML_LINK.

   Added parser feature RAPTOR_FEATURE_WWW_TIMEOUT

   Added raptor_graph_handler typedef and raptor_set_graph_handler()

   Added          raptor_www_final_uri_handler         typedef         and
   raptor_www_set_final_uri_handler()

   Added raptor_www_set_connection_timeout()

   Added raptor_www_get_final_uri()

   1.4.15
   No changes.

   1.4.14
   Add   two    new    exported    strings    raptor_license_string    and
   raptor_home_url_string.

   Added      new      features      for     the     'dot'     serializer:
   RAPTOR_FEATURE_RESOURCE_BORDER,          RAPTOR_FEATURE_LITERAL_BORDER,
   RAPTOR_FEATURE_BNODE_BORDER,              RAPTOR_FEATURE_RESOURCE_FILL,
   RAPTOR_FEATURE_LITERAL_FILL and RAPTOR_FEATURE_BNODE_FILL

   Added raptor_parser_generate_id()

   Added raptor_iostream_write_string_turtle()

   1.4.13
   No API changes.

   1.4.12
   No API changes.

   1.4.11
   Added raptor_get_feature_count()

   Added raptor_get_need_base_uri()

   Added parser feature RAPTOR_FEATURE_NO_NET

   Added raptor_www_set_uri_filter(), raptor_parser_set_uri_filter()  with
   filter type raptor_uri_filter_func

   1.4.10
   No API changes.

   1.4.9
   Added raptor_parser_get_accept_header()

   Added raptor_xml_element_is_empty()

   Added raptor_qname_get_namespace()

   Added raptor_iostream_write_uri()

   Added raptor_namespaces_qname_from_uri().

   Added raptor_namespace_get_counted_prefix()

   Added raptor_serialize_set_namespace_from_namespace()

   Deprecated           raptor_uri_is_file_uri()          for          new
   raptor_uri_string_is_file_uri().

   Added              raptor_xml_element_get_attributes()              and
   raptor_xml_element_get_attributes_count()

   1.4.8
   Added raptor_set_namespace_handler().

   Added       XML       1.1       serializing       support,      feature
   RAPTOR_FEATURE_WRITER_XML_VERSION   with   shortname   xmlVersion   for
   serializer  and  xml  writer  classes  to support it.  Added XML writer
   feature RAPTOR_FEATURE_WRITER_XML_DECLARATION to control generation  of
   the       XML       declaration.        Added       new       functions
   raptor_xml_any_escape_string()                                      and
   raptor_iostream_write_xml_any_escaped_string()  to allow generating XML
   1.1 or XML 1.0.

   RAPTOR_IDENTIFIER_TYPE_PREDICATE  will  no  longer  be  generated  from
   version  1.4.9  onwards  as  the type of returned statement predicates.
   RAPTOR_IDENTIFIER_TYPE_RESOURCE will be returned.

   RAPTOR_IDENTIFIER_TYPE_ORDINAL may no longer be generated from  version
   1.4.9 onwards, RAPTOR_IDENTIFIER_TYPE_RESOURCE may replace it.

   1.4.7
   No changes.

   1.4.6
   No changes.

   1.4.5
   Deprecated  raptor_ntriples_string_as_utf8_string()  (never  documented
   above) since it can only work with a raptor_parser object  which  makes
   it rather unusable alone.

   Added     XML     writer     features     and     support     functions
   raptor_xml_writer_features_enumerate(),
   raptor_xml_writer_set_feature(),
   raptor_xml_writer_set_feature_string(), raptor_xml_writer_get_feature()
   and raptor_xml_writer_get_feature_string()

   1.4.3
   Added  XML  Writer  class  (raptor_xml_writer)  and  XML  Element class
   (raptor_xml_element)

   Added                               raptor_parser_get_feature_string(),
   raptor_parser_set_feature_string(),
   raptor_serializer_set_feature_string(),
   raptor_serializer_get_feature_string() and raptor_feature_value_type().

   Added  raptor_serializer_set_namespace, raptor_serializer_set_feature()
   and raptor_serializer_get_feature().

   Added                                  raptor_new_namespace_from_uri(),
   raptor_new_namespace_parts_from_string(),                         Added
   raptor_namespaces_find_namespace_by_uri().                          and
   raptor_iostream_write_namespace()  to  write a namespace declaration to
   an iostream.

   Added       copy       constructor       raptor_qname_copy()        and
   raptor_iostream_write_qname() to write a qname to an iostream.

   Added raptor_sequence_join() to join two sequences, leaving one empty.

   Added  raptor_iostream_write_stringbuffer()  to write a stringbuffer to
   an iostream.

   Added     N-Triples     raptor_iostream_write_string_ntriples()     and
   raptor_iostream_write_statement_ntriples()    utility   functions   for
   writing to raptor_iostreams.

   Added                      raptor_uri_to_relative_counted_uri_string(),
   raptor_uri_to_relative_uri_string().                raptor_uri_print(),
   raptor_uri_to_counted_string() and raptor_uri_to_string()

   Added unicode name checking utility functions for XML 1.0 and  XML  1.1
   name    starting    character    and    continued    name    character.
   raptor_unicode_is_xml10_namestartchar raptor_unicode_is_xml10_namechar,
   raptor_unicode_is_xml11_namechar                                    and
   raptor_unicode_is_xml11_namestartchar.

   Added raptor_xml_name_check to check if a name is a legal  XML  1.0  or
   1.0  name.   and  raptor_iostream_write_xml_escaped_string  to write an
   XML-escaped string to an iostream.

   Added UTF8-checking utility function raptor_utf8_check.

   1.4.2
   No changes.

   1.4.1
   The raptor_xml_escape_string now returns <0 on failure rather  than  0,
   so that if an empty string is escaped, 0 bytes required is returned.

   1.4.0
   Added  new raptor_serializer class supporting RDF/XML (name rdfxml) and
   N-Triples (name ntriples).
   Added new raptor_iostream class
   Added raptor_stringbuffer_copy_to_string to allow efficient copy-out of
   a constructed string.
   Added  raptor_www_fetch_to_string to allow retrieving of web content as
   a single string.

   1.3.3
   Added raptor_calloc_memory to provide a calloc inside raptor.
   Added feature check_rdf_id (see raptor_set_feature documentation).

   1.3.2
   Added raptor_alloc_memory to allocate memory inside raptor.

   Added accessor functions for the public raptor_locator structure:

   raptor_locator_line
   raptor_locator_column
   raptor_locator_byte
   raptor_locator_file
   raptor_locator_uri

   1.3.1
   Correct raptor_print_statement declaration argument statement  to  have
   one less 'const', to match the code.

   1.3.0
   Added   the  following  parser  methods,  utility  methods  and  helper
   functions:

   raptor_new_parser_for_content (Parser class constructor)
   raptor_get_mime_type
   raptor_get_feature
   raptor_syntax_name_check
   raptor_guess_parser_name
   raptor_features_enumerate
   raptor_feature_from_uri
   raptor_www_set_http_accept (WWW class)

   Changed raptor_set_feature to now return an int success or failure.

   Added the following functions:
   raptor_free_memory
   raptor_unicode_char_to_utf8
   raptor_utf8_to_unicode_char
   raptor_vsnprintf

   Added the raptor_sequence class, its constructor,  destructor,  methods
   and helper functions.

   Added  the  raptor_stringbuffer  class  and constructor, destructor and
   methods.

   Deprecated  raptor_print_statement_detailed  always  intended   to   be
   internal.

   1.2.0
   Added  raptor_syntaxes_enumerate to get full information on syntax mime
   type and URIs as well as name and label.

   N-Triples Plus parser renamed to Turtle (name turtle)

   1.1.0
   Added N-Triples Plus parser (name ntriples-plus)

   Made URI class constructors, methods and factory  methods  as  well  as
   some  other  utility functions using or returning URIs or literals take
   unsigned char* rather than char*.  The affected calls are:

   URI factory methods changed to all take/return unsigned char*  for  URI
   strings:
   raptor_new_uri_func
   raptor_new_uri_from_local_name_func
   raptor_new_uri_relative_to_base_func
   raptor_uri_as_string_func
   raptor_uri_as_counted_string_func

   Constructors  and methods changed to take/return unsigned char* for URI
   strings:
   raptor_statement_part_as_counted_string
   raptor_statement_part_as_string
   raptor_new_uri
   raptor_new_uri_from_uri_local_name
   raptor_new_uri_relative_to_base
   raptor_uri_as_string
   raptor_uri_as_counted_string
   raptor_print_ntriples_string

   Changed to use unsigned char* for URI strings, char* for filenames:
   raptor_uri_resolve_uri_reference
   raptor_uri_filename_to_uri_string
   raptor_uri_uri_string_to_filename
   raptor_uri_uri_string_to_filename_fragment
   raptor_uri_is_file_uri

   Changed to return unsigned char* for UTF8 string:
   raptor_ntriples_string_as_utf8_string

   Added raptor_parsers_enumerate to discover supported parsers.

   Added raptor_uri_uri_string_to_filename_fragment with fragment  arg  to
   return the URI fragment.

   Made  the  raptor_namespace,  raptor_namespace_stack  and  raptor_qname
   class and APIs public.

   Added feature non_nfc_fatal (see raptor_set_feature documentation).

   1.0.0
   Removed the following  deprecated  methods  and  functions  (see  0.9.6
   changes for the new names):
   raptor_free,   raptor_new,  raptor_ntriples_free,  raptor_ntriples_new,
   raptor_ntriples_parse_file,          raptor_ntriples_set_error_handler,
   raptor_ntriples_set_fatal_error_handler,
   raptor_ntriples_set_statement_handler and raptor_parser_abort.

   Added  raptor_parse_file_stream  for  reading  FILE*  streams   without
   necessarily having a file.

   0.9.12
   Added  raptor_new_uri_for_retrieval  to  turn  URI references into URIs
   suitable for retrieval (no fragments).

   0.9.11
   Added raptor_get_name and raptor_get_label.

   raptor_xml_escape_string now takes error message handler, data pointer,
   loses parser argument.

   Added           raptor_set_default_generate_id_parameters           and
   raptor_set_generate_id_handler to control  the  default  generation  of
   IDs, allow full customisation.

   0.9.10
   Added                    raptor_set_parser_strict                   and
   raptor_www_no_www_library_init_finish.

   raptor_xml_escape_string now takes an output string length pointer.

   Added                          raptor_statement_part_as_counted_string,
   raptor_statement_part_as_string and raptor_parse_abort.

   Deprecated raptor_parser_abort.

   0.9.9
   Added  raptor_www  class and all its constructors, destructor, methods,
   calls.

   Added              raptor_parse_uri,               raptor_parser_abort,
   raptor_ntriples_term_as_string and raptor_xml_escape_string.

   0.9.7
   raptor_parse_chunk,  raptor_new_uri_from_id, arguments are now unsigned
   char.

   Added raptor_new_uri_for_xmlbase.

   0.9.6
   In this version, the raptor/ntriples parser calling APIs were modified.
   The following table lists the changes:

   OLD API                                  NEW API (0.9.6+)
   raptor_new()                             raptor_new_parser("rdfxml")
   ntriples_new()                           raptor_new_parser("ntriples")
   raptor_free                              raptor_free_parser
   ntriples_free                            raptor_ntriples_parser
   raptor_ntriples_parse_file               raptor_parse_file
   raptor_ntriples_set_error_handler        raptor_set_error_handler
   raptor_ntriples_set_fatal_error_handler  raptor_set_fatal_error_handler
   raptor_ntriples_set_statement_handler    raptor_set_statement_handler

CONFORMING TO

   RDF/XML  Syntax  (Revised),  Dave  Beckett  (ed.)   W3C Recommendation,
   http://www.w3.org/TR/rdf-syntax-grammar/     http://www.w3.org/TR/rdf-
   syntax-grammar/

   N-Triples,  in  RDF  Test Cases, Jan Grant and Dave Beckett (eds.)  W3C
   Recommendation,            http://www.w3.org/TR/rdf-testcases/#ntriples
   http://www.w3.org/TR/rdf-testcases/#ntriples

   Turtle     -    Terse    RDF    Triple    Language,    Dave    Beckett,
   http://www.dajobe.org/2004/01/turtle/
   http://www.dajobe.org/2004/01/turtle/

   RSS     0.91     spec     revision     3,    Dan    Libby,    Netscape,
   http://my.netscape.com/publish/formats/rss-spec-0.91.html
   http://my.netscape.com/publish/formats/rss-spec-0.91.html

   RDF    Site    Summary    (RSS)    1.0,    http://purl.org/rss/1.0/spec
   http://purl.org/rss/1.0/spec

   Atom       1.0       syndication        format,        RFC        4287,
   http://www.ietf.org/rfc/rfc4287.txt
   http://www.ietf.org/rfc/rfc4287.txt

   Gleaning Resource Descriptions from Dialects of Languages (GRDDL),  Dan
   Connolly       (ed.),       W3C       Recommendation,       2007-09-11,
   http://www.w3.org/TR/2007/REC-grddl-20070911/
   http://www.w3.org/TR/2007/REC-grddl-20070911/

   RDFa  in  XHTML:  Syntax and Processing, Ben Adida, Mark Birbeck, Shane
   McCarron, Steven Pemberton (eds.)
    W3C  Recommendation,  2008-10-14,  http://www.w3.org/TR/2008/REC-rdfa-
   syntax-20081014/ http://www.w3.org/TR/2008/REC-rdfa-syntax-20081014/

SEE ALSO

   rapper(1),raptor-config(1)

AUTHOR

   Dave Beckett - http://www.dajobe.org/ http://www.dajobe.org/

                              2010-01-29                      libraptor(3)





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