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 LIBXML_ZLIB_ENABLED
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
51static xlinkHandlerPtr xlinkDefaultHandler = NULL;
52static xlinkNodeDetectFunc xlinkDefaultDetect = NULL;
53
54/**
55 * xlinkGetDefaultHandler:
56 *
57 * Get the default xlink handler.
58 *
59 * Returns the current xlinkHandlerPtr value.
60 */
61xlinkHandlerPtr
62xlinkGetDefaultHandler(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 */
73void
74xlinkSetDefaultHandler(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 */
85xlinkNodeDetectFunc
86xlinkGetDefaultDetect (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 */
96void
97xlinkSetDefaultDetect (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 */
122xlinkType
123xlinkIsLink (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"
184