third_party/libxml/src/xlink.c

   1 /*
   2  * xlink.c : implementation of the hyperlinks detection module
   3  *           This version supports both XML XLinks and HTML simple links
   4  *
   5  * See Copyright for the status of this software.
   6  *
   7  * daniel@veillard.com
   8  */
   9
  10
  11 #define IN_LIBXML
  12 #include "libxml.h"
  13
  14 #ifdef LIBXML_XPTR_ENABLED
  15 #include <string.h> /* for memset() only */
  16 #ifdef HAVE_CTYPE_H
  17 #include <ctype.h>
  18 #endif
  19 #ifdef HAVE_STDLIB_H
  20 #include <stdlib.h>
  21 #endif
  22 #ifdef HAVE_SYS_STAT_H
  23 #include <sys/stat.h>
  24 #endif
  25 #ifdef HAVE_FCNTL_H
  26 #include <fcntl.h>
  27 #endif
  28 #ifdef HAVE_UNISTD_H
  29 #include <unistd.h>
  30 #endif
  31 #ifdef HAVE_ZLIB_H
  32 #include <zlib.h>
  33 #endif
  34
  35 #include <libxml/xmlmemory.h>
  36 #include <libxml/tree.h>
  37 #include <libxml/parser.h>
  38 #include <libxml/valid.h>
  39 #include <libxml/xlink.h>
  40 #include <libxml/globals.h>
  41
  42 #define XLINK_NAMESPACE (BAD_CAST "http://www.w3.org/1999/xlink/namespace/")
  43 #define XHTML_NAMESPACE (BAD_CAST "http://www.w3.org/1999/xhtml/")
  44
  45 /****************************************************************
  46  *                                                              *
  47  *           Default setting and related functions              *
  48  *                                                              *
  49  ****************************************************************/
  50
  51 static xlinkHandlerPtr xlinkDefaultHandler = NULL;
  52 static xlinkNodeDetectFunc      xlinkDefaultDetect = NULL;
  53
  54 /**
  55  * xlinkGetDefaultHandler:
  56  *
  57  * Get the default xlink handler.
  58  *
  59  * Returns the current xlinkHandlerPtr value.
  60  */
  61 xlinkHandlerPtr
  62 xlinkGetDefaultHandler(void) {
  63     return(xlinkDefaultHandler);
  64 }
  65
  66
  67 /**
  68  * xlinkSetDefaultHandler:
  69  * @handler:  the new value for the xlink handler block
  70  *
  71  * Set the default xlink handlers
  72  */
  73 void
  74 xlinkSetDefaultHandler(xlinkHandlerPtr handler) {
  75     xlinkDefaultHandler = handler;
  76 }
  77
  78 /**
  79  * xlinkGetDefaultDetect:
  80  *
  81  * Get the default xlink detection routine
  82  *
  83  * Returns the current function or NULL;
  84  */
  85 xlinkNodeDetectFunc
  86 xlinkGetDefaultDetect   (void) {
  87     return(xlinkDefaultDetect);
  88 }
  89
  90 /**
  91  * xlinkSetDefaultDetect:
  92  * @func: pointer to the new detection routine.
  93  *
  94  * Set the default xlink detection routine
  95  */
  96 void
  97 xlinkSetDefaultDetect   (xlinkNodeDetectFunc func) {
  98     xlinkDefaultDetect = func;
  99 }
 100
 101 /****************************************************************
 102  *                                                              *
 103  *                  The detection routines                      *
 104  *                                                              *
 105  ****************************************************************/
 106
 107
 108 /**
 109  * xlinkIsLink:
 110  * @doc:  the document containing the node
 111  * @node:  the node pointer itself
 112  *
 113  * Check whether the given node carries the attributes needed
 114  * to be a link element (or is one of the linking elements issued
 115  * from the (X)HTML DtDs).
 116  * This routine don't try to do full checking of the link validity
 117  * but tries to detect and return the appropriate link type.
 118  *
 119  * Returns the xlinkType of the node (XLINK_TYPE_NONE if there is no
 120  *         link detected.
 121  */
 122 xlinkType
 123 xlinkIsLink     (xmlDocPtr doc, xmlNodePtr node) {
 124     xmlChar *type = NULL, *role = NULL;
 125     xlinkType ret = XLINK_TYPE_NONE;
 126
 127     if (node == NULL) return(XLINK_TYPE_NONE);
 128     if (doc == NULL) doc = node->doc;
 129     if ((doc != NULL) && (doc->type == XML_HTML_DOCUMENT_NODE)) {
 130         /*
 131          * This is an HTML document.
 132          */
 133     } else if ((node->ns != NULL) &&
 134                (xmlStrEqual(node->ns->href, XHTML_NAMESPACE))) {
 135         /*
 136          * !!!! We really need an IS_XHTML_ELEMENT function from HTMLtree.h @@@
 137          */
 138         /*
 139          * This is an XHTML element within an XML document
 140          * Check whether it's one of the element able to carry links
 141          * and in that case if it holds the attributes.
 142          */
 143     }
 144
 145     /*
 146      * We don't prevent a-priori having XML Linking constructs on
 147      * XHTML elements
 148      */
 149     type = xmlGetNsProp(node, BAD_CAST"type", XLINK_NAMESPACE);
 150     if (type != NULL) {
 151         if (xmlStrEqual(type, BAD_CAST "simple")) {
 152             ret = XLINK_TYPE_SIMPLE;
 153         } else if (xmlStrEqual(type, BAD_CAST "extended")) {
 154             role = xmlGetNsProp(node, BAD_CAST "role", XLINK_NAMESPACE);
 155             if (role != NULL) {
 156                 xmlNsPtr xlink;
 157                 xlink = xmlSearchNs(doc, node, XLINK_NAMESPACE);
 158                 if (xlink == NULL) {
 159                     /* Humm, fallback method */
 160                     if (xmlStrEqual(role, BAD_CAST"xlink:external-linkset"))
 161                         ret = XLINK_TYPE_EXTENDED_SET;
 162                 } else {
 163                     xmlChar buf[200];
 164                     snprintf((char *) buf, sizeof(buf), "%s:external-linkset",
 165                              (char *) xlink->prefix);
 166                     buf[sizeof(buf) - 1] = 0;
 167                     if (xmlStrEqual(role, buf))
 168                         ret = XLINK_TYPE_EXTENDED_SET;
 169
 170                 }
 171
 172             }
 173             ret = XLINK_TYPE_EXTENDED;
 174         }
 175     }
 176
 177     if (type != NULL) xmlFree(type);
 178     if (role != NULL) xmlFree(role);
 179     return(ret);
 180 }
 181 #endif /* LIBXML_XPTR_ENABLED */
 182 #define bottom_xlink
 183 #include "elfgcchack.h"