blob: cb373024c4a43a992bd819c7ae082f47f34365db [file] [log] [blame]
Owen Taylor3473f882001-02-23 17:55:21 +00001/*
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 *
Daniel Veillardc5d64342001-06-24 12:13:24 +00007 * daniel@veillard.com
Owen Taylor3473f882001-02-23 17:55:21 +00008 */
9
10
Bjorn Reese70a9da52001-04-21 16:57:29 +000011#include "libxml.h"
Owen Taylor3473f882001-02-23 17:55:21 +000012
Owen Taylor3473f882001-02-23 17:55:21 +000013#include <string.h> /* for memset() only */
14#ifdef HAVE_CTYPE_H
15#include <ctype.h>
16#endif
17#ifdef HAVE_STDLIB_H
18#include <stdlib.h>
19#endif
20#ifdef HAVE_SYS_STAT_H
21#include <sys/stat.h>
22#endif
23#ifdef HAVE_FCNTL_H
24#include <fcntl.h>
25#endif
26#ifdef HAVE_UNISTD_H
27#include <unistd.h>
28#endif
29#ifdef HAVE_ZLIB_H
30#include <zlib.h>
31#endif
32
33#include <libxml/xmlmemory.h>
34#include <libxml/tree.h>
35#include <libxml/parser.h>
36#include <libxml/valid.h>
37#include <libxml/xlink.h>
38
39#define XLINK_NAMESPACE (BAD_CAST "http://www.w3.org/1999/xlink/namespace/")
40#define XHTML_NAMESPACE (BAD_CAST "http://www.w3.org/1999/xhtml/")
41
42/****************************************************************
43 * *
44 * Default setting and related functions *
45 * *
46 ****************************************************************/
47
48xlinkHandlerPtr xlinkDefaultHandler = NULL;
49xlinkNodeDetectFunc xlinkDefaultDetect = NULL;
50
51/**
52 * xlinkGetDefaultHandler:
53 *
54 * Get the default xlink handler.
55 *
56 * Returns the current xlinkHandlerPtr value.
57 */
58xlinkHandlerPtr
59xlinkGetDefaultHandler(void) {
60 return(xlinkDefaultHandler);
61}
62
63
64/**
65 * xlinkSetDefaultHandler:
66 * @handler: the new value for the xlink handler block
67 *
68 * Set the default xlink handlers
69 */
70void
71xlinkSetDefaultHandler(xlinkHandlerPtr handler) {
72 xlinkDefaultHandler = handler;
73}
74
75/**
76 * xlinkGetDefaultDetect:
77 *
78 * Get the default xlink detection routine
79 *
80 * Returns the current function or NULL;
81 */
82xlinkNodeDetectFunc
83xlinkGetDefaultDetect (void) {
84 return(xlinkDefaultDetect);
85}
86
87/**
88 * xlinkSetDefaultDetect:
89 * @func: pointer to the new detction routine.
90 *
91 * Set the default xlink detection routine
92 */
93void
94xlinkSetDefaultDetect (xlinkNodeDetectFunc func) {
95 xlinkDefaultDetect = func;
96}
97
98/****************************************************************
99 * *
100 * The detection routines *
101 * *
102 ****************************************************************/
103
104
105/**
106 * xlinkIsLink:
107 * @doc: the document containing the node
108 * @node: the node pointer itself
109 *
110 * Check whether the given node carries the attributes needed
111 * to be a link element (or is one of the linking elements issued
112 * from the (X)HTML DtDs).
113 * This routine don't try to do full checking of the link validity
114 * but tries to detect and return the appropriate link type.
115 *
116 * Returns the xlinkType of the node (XLINK_TYPE_NONE if there is no
117 * link detected.
118 */
119xlinkType
120xlinkIsLink (xmlDocPtr doc, xmlNodePtr node) {
121 xmlChar *type = NULL, *role = NULL;
122 xlinkType ret = XLINK_TYPE_NONE;
123
124 if (node == NULL) return(XLINK_TYPE_NONE);
125 if (doc == NULL) doc = node->doc;
126 if ((doc != NULL) && (doc->type == XML_HTML_DOCUMENT_NODE)) {
127 /*
128 * This is an HTML document.
129 */
130 } else if ((node->ns != NULL) &&
131 (xmlStrEqual(node->ns->href, XHTML_NAMESPACE))) {
132 /*
133 * !!!! We really need an IS_XHTML_ELEMENT function from HTMLtree.h @@@
134 */
135 /*
136 * This is an XHTML element within an XML document
137 * Check whether it's one of the element able to carry links
138 * and in that case if it holds the attributes.
139 */
140 }
141
142 /*
143 * We don't prevent a-priori having XML Linking constructs on
144 * XHTML elements
145 */
146 type = xmlGetNsProp(node, BAD_CAST"type", XLINK_NAMESPACE);
147 if (type != NULL) {
148 if (!xmlStrEqual(type, BAD_CAST "simple")) {
149 ret = XLINK_TYPE_SIMPLE;
150 } if (!xmlStrEqual(type, BAD_CAST "extended")) {
151 role = xmlGetNsProp(node, BAD_CAST "role", XLINK_NAMESPACE);
152 if (role != NULL) {
153 xmlNsPtr xlink;
154 xlink = xmlSearchNs(doc, node, XLINK_NAMESPACE);
155 if (xlink == NULL) {
156 /* Humm, fallback method */
157 if (xmlStrEqual(role, BAD_CAST"xlink:external-linkset"))
158 ret = XLINK_TYPE_EXTENDED_SET;
159 } else {
160 xmlChar buf[200];
Owen Taylor3473f882001-02-23 17:55:21 +0000161 snprintf((char *) buf, sizeof(buf), "%s:external-linkset",
162 (char *) xlink->prefix);
Owen Taylor3473f882001-02-23 17:55:21 +0000163 buf[sizeof(buf) - 1] = 0;
164 if (xmlStrEqual(role, buf))
165 ret = XLINK_TYPE_EXTENDED_SET;
166
167 }
168
169 }
170 ret = XLINK_TYPE_EXTENDED;
171 }
172 }
173
174 if (type != NULL) xmlFree(type);
175 if (role != NULL) xmlFree(role);
176 return(ret);
177}