text: /*
   * xlink.c : implementation of the hyperlinks detection module
   *           This version supports both XML XLinks and HTML simple links
   *
   * See Copyright for the status of this software.
   *
   * daniel@veillard.com
   */
  
  
  #define IN_LIBXML
  #include "libxml.h"
  
  #ifdef LIBXML_XPTR_ENABLED
  #include <string.h> /* for memset() only */
  #ifdef HAVE_CTYPE_H
  #include <ctype.h>
  #endif
  #ifdef HAVE_STDLIB_H
  #include <stdlib.h>
  #endif
  #ifdef HAVE_SYS_STAT_H
  #include <sys/stat.h>
  #endif
  #ifdef HAVE_FCNTL_H
  #include <fcntl.h>
  #endif
  #ifdef HAVE_UNISTD_H
  #include <unistd.h>
  #endif
  #ifdef LIBXML_ZLIB_ENABLED
  #include <zlib.h>
  #endif
  
  #include <libxml/xmlmemory.h>
  #include <libxml/tree.h>
  #include <libxml/parser.h>
  #include <libxml/valid.h>
  #include <libxml/xlink.h>
  #include <libxml/globals.h>
  
  #define XLINK_NAMESPACE (BAD_CAST "http://www.w3.org/1999/xlink/namespace/")
  #define XHTML_NAMESPACE (BAD_CAST "http://www.w3.org/1999/xhtml/")
  
  /****************************************************************
   *								*
   *           Default setting and related functions		*
   *								*
   ****************************************************************/
  
  static xlinkHandlerPtr xlinkDefaultHandler = NULL;
  static xlinkNodeDetectFunc	xlinkDefaultDetect = NULL;
  
  /**
   * xlinkGetDefaultHandler:
   *
   * Get the default xlink handler.
   *
   * Returns the current xlinkHandlerPtr value.
   */
  xlinkHandlerPtr
  xlinkGetDefaultHandler(void) {
      return(xlinkDefaultHandler);
  }
  
  
  /**
   * xlinkSetDefaultHandler:
   * @handler:  the new value for the xlink handler block
   *
   * Set the default xlink handlers
   */
  void
  xlinkSetDefaultHandler(xlinkHandlerPtr handler) {
      xlinkDefaultHandler = handler;
  }
  
  /**
   * xlinkGetDefaultDetect:
   *
   * Get the default xlink detection routine
   *
   * Returns the current function or NULL;
   */
  xlinkNodeDetectFunc
  xlinkGetDefaultDetect	(void) {
      return(xlinkDefaultDetect);
  }
  
  /**
   * xlinkSetDefaultDetect:
   * @func: pointer to the new detection routine.
   *
   * Set the default xlink detection routine
   */
  void
  xlinkSetDefaultDetect	(xlinkNodeDetectFunc func) {
      xlinkDefaultDetect = func;
  }
  
  /****************************************************************
   *								*
   *                  The detection routines			*
   *								*
   ****************************************************************/
  
  
  /**
   * xlinkIsLink:
   * @doc:  the document containing the node
   * @node:  the node pointer itself
   *
   * Check whether the given node carries the attributes needed
   * to be a link element (or is one of the linking elements issued
   * from the (X)HTML DtDs).
   * This routine don't try to do full checking of the link validity
   * but tries to detect and return the appropriate link type.
   *
   * Returns the xlinkType of the node (XLINK_TYPE_NONE if there is no
   *         link detected.
   */
  xlinkType
  xlinkIsLink	(xmlDocPtr doc, xmlNodePtr node) {
      xmlChar *type = NULL, *role = NULL;
      xlinkType ret = XLINK_TYPE_NONE;
  
      if (node == NULL) return(XLINK_TYPE_NONE);
      if (doc == NULL) doc = node->doc;
      if ((doc != NULL) && (doc->type == XML_HTML_DOCUMENT_NODE)) {
          /*
  	 * This is an HTML document.
  	 */
      } else if ((node->ns != NULL) &&
                 (xmlStrEqual(node->ns->href, XHTML_NAMESPACE))) {
  	/*
  	 * !!!! We really need an IS_XHTML_ELEMENT function from HTMLtree.h @@@
  	 */
          /*
  	 * This is an XHTML element within an XML document
  	 * Check whether it's one of the element able to carry links
  	 * and in that case if it holds the attributes.
  	 */
      }
  
      /*
       * We don't prevent a-priori having XML Linking constructs on
       * XHTML elements
       */
      type = xmlGetNsProp(node, BAD_CAST"type", XLINK_NAMESPACE);
      if (type != NULL) {
  	if (xmlStrEqual(type, BAD_CAST "simple")) {
              ret = XLINK_TYPE_SIMPLE;
  	} else if (xmlStrEqual(type, BAD_CAST "extended")) {
  	    role = xmlGetNsProp(node, BAD_CAST "role", XLINK_NAMESPACE);
  	    if (role != NULL) {
  		xmlNsPtr xlink;
  		xlink = xmlSearchNs(doc, node, XLINK_NAMESPACE);
  		if (xlink == NULL) {
  		    /* Humm, fallback method */
  		    if (xmlStrEqual(role, BAD_CAST"xlink:external-linkset"))
  			ret = XLINK_TYPE_EXTENDED_SET;
  		} else {
  		    xmlChar buf[200];
  		    snprintf((char *) buf, sizeof(buf), "%s:external-linkset",
  			     (char *) xlink->prefix);
                      buf[sizeof(buf) - 1] = 0;
  		    if (xmlStrEqual(role, buf))
  			ret = XLINK_TYPE_EXTENDED_SET;
  
  		}
  
  	    }
  	    ret = XLINK_TYPE_EXTENDED;
  	}
      }
  
      if (type != NULL) xmlFree(type);
      if (role != NULL) xmlFree(role);
      return(ret);
  }
  #endif /* LIBXML_XPTR_ENABLED */
  #define bottom_xlink
  #include "elfgcchack.h"
  