1/*
2 * This file is part of the XSL implementation.
3 *
4 * Copyright (C) 2004, 2005, 2006, 2008, 2012 Apple Inc. All rights reserved.
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Library General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14 * Library General Public License for more details.
15 *
16 * You should have received a copy of the GNU Library General Public License
17 * along with this library; see the file COPYING.LIB.  If not, write to
18 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
19 * Boston, MA 02110-1301, USA.
20 */
21
22#include "config.h"
23#include "XSLStyleSheet.h"
24
25#if ENABLE(XSLT)
26
27#include "CachedResourceLoader.h"
28#include "Document.h"
29#include "Frame.h"
30#include "Node.h"
31#include "Page.h"
32#include "PageConsole.h"
33#include "TransformSource.h"
34#include "XMLDocumentParser.h"
35#include "XMLDocumentParserScope.h"
36#include "XSLImportRule.h"
37#include "XSLTProcessor.h"
38#include <wtf/text/CString.h>
39
40#include <libxml/uri.h>
41#include <libxslt/xsltutils.h>
42
43#if PLATFORM(MAC)
44#include "SoftLinking.h"
45#endif
46
47#if PLATFORM(MAC)
48SOFT_LINK_LIBRARY(libxslt)
49SOFT_LINK(libxslt, xsltIsBlank, int, (xmlChar *str), (str))
50SOFT_LINK(libxslt, xsltGetNsProp, xmlChar *, (xmlNodePtr node, const xmlChar *name, const xmlChar *nameSpace), (node, name, nameSpace))
51SOFT_LINK(libxslt, xsltParseStylesheetDoc, xsltStylesheetPtr, (xmlDocPtr doc), (doc))
52SOFT_LINK(libxslt, xsltLoadStylesheetPI, xsltStylesheetPtr, (xmlDocPtr doc), (doc))
53#endif
54
55namespace WebCore {
56
57XSLStyleSheet::XSLStyleSheet(XSLImportRule* parentRule, const String& originalURL, const KURL& finalURL)
58    : m_ownerNode(0)
59    , m_originalURL(originalURL)
60    , m_finalURL(finalURL)
61    , m_isDisabled(false)
62    , m_embedded(false)
63    , m_processed(false) // Child sheets get marked as processed when the libxslt engine has finally seen them.
64    , m_stylesheetDoc(0)
65    , m_stylesheetDocTaken(false)
66    , m_parentStyleSheet(parentRule ? parentRule->parentStyleSheet() : 0)
67{
68}
69
70XSLStyleSheet::XSLStyleSheet(Node* parentNode, const String& originalURL, const KURL& finalURL,  bool embedded)
71    : m_ownerNode(parentNode)
72    , m_originalURL(originalURL)
73    , m_finalURL(finalURL)
74    , m_isDisabled(false)
75    , m_embedded(embedded)
76    , m_processed(true) // The root sheet starts off processed.
77    , m_stylesheetDoc(0)
78    , m_stylesheetDocTaken(false)
79    , m_parentStyleSheet(0)
80{
81}
82
83XSLStyleSheet::~XSLStyleSheet()
84{
85    if (!m_stylesheetDocTaken)
86        xmlFreeDoc(m_stylesheetDoc);
87
88    for (unsigned i = 0; i < m_children.size(); ++i) {
89        ASSERT(m_children.at(i)->parentStyleSheet() == this);
90        m_children.at(i)->setParentStyleSheet(0);
91    }
92}
93
94bool XSLStyleSheet::isLoading() const
95{
96    for (unsigned i = 0; i < m_children.size(); ++i) {
97        if (m_children.at(i)->isLoading())
98            return true;
99    }
100    return false;
101}
102
103void XSLStyleSheet::checkLoaded()
104{
105    if (isLoading())
106        return;
107    if (XSLStyleSheet* styleSheet = parentStyleSheet())
108        styleSheet->checkLoaded();
109    if (ownerNode())
110        ownerNode()->sheetLoaded();
111}
112
113xmlDocPtr XSLStyleSheet::document()
114{
115    if (m_embedded && ownerDocument() && ownerDocument()->transformSource())
116        return (xmlDocPtr)ownerDocument()->transformSource()->platformSource();
117    return m_stylesheetDoc;
118}
119
120void XSLStyleSheet::clearDocuments()
121{
122    m_stylesheetDoc = 0;
123    for (unsigned i = 0; i < m_children.size(); ++i) {
124        XSLImportRule* import = m_children.at(i).get();
125        if (import->styleSheet())
126            import->styleSheet()->clearDocuments();
127    }
128}
129
130CachedResourceLoader* XSLStyleSheet::cachedResourceLoader()
131{
132    Document* document = ownerDocument();
133    if (!document)
134        return 0;
135    return document->cachedResourceLoader();
136}
137
138bool XSLStyleSheet::parseString(const String& string)
139{
140    // Parse in a single chunk into an xmlDocPtr
141    const UChar BOM = 0xFEFF;
142    const unsigned char BOMHighByte = *reinterpret_cast<const unsigned char*>(&BOM);
143    if (!m_stylesheetDocTaken)
144        xmlFreeDoc(m_stylesheetDoc);
145    m_stylesheetDocTaken = false;
146
147    PageConsole* console = 0;
148    Frame* frame = ownerDocument()->frame();
149    if (frame && frame->page())
150        console = frame->page()->console();
151
152    XMLDocumentParserScope scope(cachedResourceLoader(), XSLTProcessor::genericErrorFunc, XSLTProcessor::parseErrorFunc, console);
153
154    const char* buffer = reinterpret_cast<const char*>(string.characters());
155    int size = string.length() * sizeof(UChar);
156
157    xmlParserCtxtPtr ctxt = xmlCreateMemoryParserCtxt(buffer, size);
158    if (!ctxt)
159        return 0;
160
161    if (m_parentStyleSheet) {
162        // The XSL transform may leave the newly-transformed document
163        // with references to the symbol dictionaries of the style sheet
164        // and any of its children. XML document disposal can corrupt memory
165        // if a document uses more than one symbol dictionary, so we
166        // ensure that all child stylesheets use the same dictionaries as their
167        // parents.
168        xmlDictFree(ctxt->dict);
169        ctxt->dict = m_parentStyleSheet->m_stylesheetDoc->dict;
170        xmlDictReference(ctxt->dict);
171    }
172
173    m_stylesheetDoc = xmlCtxtReadMemory(ctxt, buffer, size,
174        finalURL().string().utf8().data(),
175        BOMHighByte == 0xFF ? "UTF-16LE" : "UTF-16BE",
176        XML_PARSE_NOENT | XML_PARSE_DTDATTR | XML_PARSE_NOWARNING | XML_PARSE_NOCDATA);
177    xmlFreeParserCtxt(ctxt);
178
179    loadChildSheets();
180
181    return m_stylesheetDoc;
182}
183
184void XSLStyleSheet::loadChildSheets()
185{
186    if (!document())
187        return;
188
189    xmlNodePtr stylesheetRoot = document()->children;
190
191    // Top level children may include other things such as DTD nodes, we ignore those.
192    while (stylesheetRoot && stylesheetRoot->type != XML_ELEMENT_NODE)
193        stylesheetRoot = stylesheetRoot->next;
194
195    if (m_embedded) {
196        // We have to locate (by ID) the appropriate embedded stylesheet element, so that we can walk the
197        // import/include list.
198        xmlAttrPtr idNode = xmlGetID(document(), (const xmlChar*)(finalURL().string().utf8().data()));
199        if (!idNode)
200            return;
201        stylesheetRoot = idNode->parent;
202    } else {
203        // FIXME: Need to handle an external URI with a # in it.  This is a pretty minor edge case, so we'll deal
204        // with it later.
205    }
206
207    if (stylesheetRoot) {
208        // Walk the children of the root element and look for import/include elements.
209        // Imports must occur first.
210        xmlNodePtr curr = stylesheetRoot->children;
211        while (curr) {
212            if (curr->type != XML_ELEMENT_NODE) {
213                curr = curr->next;
214                continue;
215            }
216            if (IS_XSLT_ELEM(curr) && IS_XSLT_NAME(curr, "import")) {
217                xmlChar* uriRef = xsltGetNsProp(curr, (const xmlChar*)"href", XSLT_NAMESPACE);
218                loadChildSheet(String::fromUTF8((const char*)uriRef));
219                xmlFree(uriRef);
220            } else
221                break;
222            curr = curr->next;
223        }
224
225        // Now handle includes.
226        while (curr) {
227            if (curr->type == XML_ELEMENT_NODE && IS_XSLT_ELEM(curr) && IS_XSLT_NAME(curr, "include")) {
228                xmlChar* uriRef = xsltGetNsProp(curr, (const xmlChar*)"href", XSLT_NAMESPACE);
229                loadChildSheet(String::fromUTF8((const char*)uriRef));
230                xmlFree(uriRef);
231            }
232            curr = curr->next;
233        }
234    }
235}
236
237void XSLStyleSheet::loadChildSheet(const String& href)
238{
239    OwnPtr<XSLImportRule> childRule = XSLImportRule::create(this, href);
240    XSLImportRule* c = childRule.get();
241    m_children.append(childRule.release());
242    c->loadSheet();
243}
244
245xsltStylesheetPtr XSLStyleSheet::compileStyleSheet()
246{
247    // FIXME: Hook up error reporting for the stylesheet compilation process.
248    if (m_embedded)
249        return xsltLoadStylesheetPI(document());
250
251    // xsltParseStylesheetDoc makes the document part of the stylesheet
252    // so we have to release our pointer to it.
253    ASSERT(!m_stylesheetDocTaken);
254    xsltStylesheetPtr result = xsltParseStylesheetDoc(m_stylesheetDoc);
255    if (result)
256        m_stylesheetDocTaken = true;
257    return result;
258}
259
260void XSLStyleSheet::setParentStyleSheet(XSLStyleSheet* parent)
261{
262    m_parentStyleSheet = parent;
263}
264
265Document* XSLStyleSheet::ownerDocument()
266{
267    for (XSLStyleSheet* styleSheet = this; styleSheet; styleSheet = styleSheet->parentStyleSheet()) {
268        Node* node = styleSheet->ownerNode();
269        if (node)
270            return node->document();
271    }
272    return 0;
273}
274
275xmlDocPtr XSLStyleSheet::locateStylesheetSubResource(xmlDocPtr parentDoc, const xmlChar* uri)
276{
277    bool matchedParent = (parentDoc == document());
278    for (unsigned i = 0; i < m_children.size(); ++i) {
279        XSLImportRule* import = m_children.at(i).get();
280        XSLStyleSheet* child = import->styleSheet();
281        if (!child)
282            continue;
283        if (matchedParent) {
284            if (child->processed())
285                continue; // libxslt has been given this sheet already.
286
287            // Check the URI of the child stylesheet against the doc URI.
288            // In order to ensure that libxml canonicalized both URLs, we get the original href
289            // string from the import rule and canonicalize it using libxml before comparing it
290            // with the URI argument.
291            CString importHref = import->href().utf8();
292            xmlChar* base = xmlNodeGetBase(parentDoc, (xmlNodePtr)parentDoc);
293            xmlChar* childURI = xmlBuildURI((const xmlChar*)importHref.data(), base);
294            bool equalURIs = xmlStrEqual(uri, childURI);
295            xmlFree(base);
296            xmlFree(childURI);
297            if (equalURIs) {
298                child->markAsProcessed();
299                return child->document();
300            }
301            continue;
302        }
303        xmlDocPtr result = import->styleSheet()->locateStylesheetSubResource(parentDoc, uri);
304        if (result)
305            return result;
306    }
307
308    return 0;
309}
310
311void XSLStyleSheet::markAsProcessed()
312{
313    ASSERT(!m_processed);
314    ASSERT(!m_stylesheetDocTaken);
315    m_processed = true;
316    m_stylesheetDocTaken = true;
317}
318
319} // namespace WebCore
320
321#endif // ENABLE(XSLT)
322