]> git.saurik.com Git - wxWidgets.git/blob - src/html/htmltag.cpp
fixed a buffer overflow (!) in wxHtmlTagsCache
[wxWidgets.git] / src / html / htmltag.cpp
1 /////////////////////////////////////////////////////////////////////////////
2 // Name: htmltag.cpp
3 // Purpose: wxHtmlTag class (represents single tag)
4 // Author: Vaclav Slavik
5 // RCS-ID: $Id$
6 // Copyright: (c) 1999 Vaclav Slavik
7 // Licence: wxWindows Licence
8 /////////////////////////////////////////////////////////////////////////////
9
10
11 #ifdef __GNUG__
12 #pragma implementation
13 #endif
14
15 #include "wx/wxprec.h"
16
17 #include "wx/defs.h"
18 #if wxUSE_HTML
19
20 #ifdef __BORDLANDC__
21 #pragma hdrstop
22 #endif
23
24 #ifndef WXPRECOMP
25 #endif
26
27 #include "wx/html/htmltag.h"
28 #include "wx/html/htmlpars.h"
29 #include "wx/colour.h"
30 #include <stdio.h> // for vsscanf
31 #include <stdarg.h>
32
33
34 //-----------------------------------------------------------------------------
35 // wxHtmlTagsCache
36 //-----------------------------------------------------------------------------
37
38 struct wxHtmlCacheItem
39 {
40 // this is "pos" value passed to wxHtmlTag's constructor.
41 // it is position of '<' character of the tag
42 int Key;
43
44 // end positions for the tag:
45 // end1 is '<' of ending tag,
46 // end2 is '>' or both are
47 // -1 if there is no ending tag for this one...
48 // or -2 if this is ending tag </...>
49 int End1, End2;
50
51 // name of this tag
52 wxChar *Name;
53 };
54
55
56 IMPLEMENT_CLASS(wxHtmlTagsCache,wxObject)
57
58 #define CACHE_INCREMENT 64
59
60 wxHtmlTagsCache::wxHtmlTagsCache(const wxString& source)
61 {
62 const wxChar *src = source.c_str();
63 int i, tg, pos, stpos;
64 int lng = source.Length();
65 wxChar tagBuffer[256];
66
67 m_Cache = NULL;
68 m_CacheSize = 0;
69 m_CachePos = 0;
70
71 pos = 0;
72 while (pos < lng)
73 {
74 if (src[pos] == wxT('<')) // tag found:
75 {
76 if (m_CacheSize % CACHE_INCREMENT == 0)
77 m_Cache = (wxHtmlCacheItem*) realloc(m_Cache, (m_CacheSize + CACHE_INCREMENT) * sizeof(wxHtmlCacheItem));
78 tg = m_CacheSize++;
79 m_Cache[tg].Key = stpos = pos++;
80
81 for ( i = 0;
82 pos < lng && i < WXSIZEOF(tagBuffer) - 1 &&
83 src[pos] != wxT('>') && !wxIsspace(src[pos]);
84 i++, pos++ )
85 {
86 tagBuffer[i] = wxToupper(src[pos]);
87 }
88 tagBuffer[i] = _T('\0');
89
90 m_Cache[tg].Name = new wxChar[i+1];
91 memcpy(m_Cache[tg].Name, tagBuffer, (i+1)*sizeof(wxChar));
92
93 while (pos < lng && src[pos] != wxT('>')) pos++;
94
95 if (src[stpos+1] == wxT('/')) // ending tag:
96 {
97 m_Cache[tg].End1 = m_Cache[tg].End2 = -2;
98 // find matching begin tag:
99 for (i = tg; i >= 0; i--)
100 if ((m_Cache[i].End1 == -1) && (wxStrcmp(m_Cache[i].Name, tagBuffer+1) == 0))
101 {
102 m_Cache[i].End1 = stpos;
103 m_Cache[i].End2 = pos + 1;
104 break;
105 }
106 }
107 else
108 {
109 m_Cache[tg].End1 = m_Cache[tg].End2 = -1;
110 }
111 }
112
113 pos++;
114 }
115
116 // ok, we're done, now we'll free .Name members of cache - we don't need it anymore:
117 for (i = 0; i < m_CacheSize; i++)
118 {
119 delete[] m_Cache[i].Name;
120 m_Cache[i].Name = NULL;
121 }
122 }
123
124 void wxHtmlTagsCache::QueryTag(int at, int* end1, int* end2)
125 {
126 if (m_Cache == NULL) return;
127 if (m_Cache[m_CachePos].Key != at)
128 {
129 int delta = (at < m_Cache[m_CachePos].Key) ? -1 : 1;
130 do
131 {
132 m_CachePos += delta;
133 }
134 while (m_Cache[m_CachePos].Key != at);
135 }
136 *end1 = m_Cache[m_CachePos].End1;
137 *end2 = m_Cache[m_CachePos].End2;
138 }
139
140
141
142
143 //-----------------------------------------------------------------------------
144 // wxHtmlTag
145 //-----------------------------------------------------------------------------
146
147 IMPLEMENT_CLASS(wxHtmlTag,wxObject)
148
149 wxHtmlTag::wxHtmlTag(wxHtmlTag *parent,
150 const wxString& source, int pos, int end_pos,
151 wxHtmlTagsCache *cache,
152 wxHtmlEntitiesParser *entParser) : wxObject()
153 {
154 /* Setup DOM relations */
155
156 m_Next = NULL;
157 m_FirstChild = m_LastChild = NULL;
158 m_Parent = parent;
159 if (parent)
160 {
161 m_Prev = m_Parent->m_LastChild;
162 if (m_Prev == NULL)
163 m_Parent->m_FirstChild = this;
164 else
165 m_Prev->m_Next = this;
166 m_Parent->m_LastChild = this;
167 }
168 else
169 m_Prev = NULL;
170
171 /* Find parameters and their values: */
172
173 int i;
174 wxChar c;
175
176 // fill-in name, params and begin pos:
177 i = pos+1;
178
179 // find tag's name and convert it to uppercase:
180 while ((i < end_pos) &&
181 ((c = source[i++]) != wxT(' ') && c != wxT('\r') &&
182 c != wxT('\n') && c != wxT('\t') &&
183 c != wxT('>')))
184 {
185 if ((c >= wxT('a')) && (c <= wxT('z')))
186 c -= (wxT('a') - wxT('A'));
187 m_Name << c;
188 }
189
190 // if the tag has parameters, read them and "normalize" them,
191 // i.e. convert to uppercase, replace whitespaces by spaces and
192 // remove whitespaces around '=':
193 if (source[i-1] != wxT('>'))
194 {
195 #define IS_WHITE(c) (c == wxT(' ') || c == wxT('\r') || \
196 c == wxT('\n') || c == wxT('\t'))
197 wxString pname, pvalue;
198 wxChar quote;
199 enum
200 {
201 ST_BEFORE_NAME = 1,
202 ST_NAME,
203 ST_BEFORE_EQ,
204 ST_BEFORE_VALUE,
205 ST_VALUE
206 } state;
207
208 quote = 0;
209 state = ST_BEFORE_NAME;
210 while (i < end_pos)
211 {
212 c = source[i++];
213
214 if (c == wxT('>') && !(state == ST_VALUE && quote != 0))
215 {
216 if (state == ST_BEFORE_EQ || state == ST_NAME)
217 {
218 m_ParamNames.Add(pname);
219 m_ParamValues.Add(wxEmptyString);
220 }
221 else if (state == ST_VALUE && quote == 0)
222 {
223 m_ParamNames.Add(pname);
224 if (entParser)
225 m_ParamValues.Add(entParser->Parse(pvalue));
226 else
227 m_ParamValues.Add(pvalue);
228 }
229 break;
230 }
231 switch (state)
232 {
233 case ST_BEFORE_NAME:
234 if (!IS_WHITE(c))
235 {
236 pname = c;
237 state = ST_NAME;
238 }
239 break;
240 case ST_NAME:
241 if (IS_WHITE(c))
242 state = ST_BEFORE_EQ;
243 else if (c == wxT('='))
244 state = ST_BEFORE_VALUE;
245 else
246 pname << c;
247 break;
248 case ST_BEFORE_EQ:
249 if (c == wxT('='))
250 state = ST_BEFORE_VALUE;
251 else if (!IS_WHITE(c))
252 {
253 m_ParamNames.Add(pname);
254 m_ParamValues.Add(wxEmptyString);
255 pname = c;
256 state = ST_NAME;
257 }
258 break;
259 case ST_BEFORE_VALUE:
260 if (!IS_WHITE(c))
261 {
262 if (c == wxT('"') || c == wxT('\''))
263 quote = c, pvalue = wxEmptyString;
264 else
265 quote = 0, pvalue = c;
266 state = ST_VALUE;
267 }
268 break;
269 case ST_VALUE:
270 if ((quote != 0 && c == quote) ||
271 (quote == 0 && IS_WHITE(c)))
272 {
273 m_ParamNames.Add(pname);
274 if (quote == 0)
275 {
276 // VS: backward compatibility, no real reason,
277 // but wxHTML code relies on this... :(
278 pvalue.MakeUpper();
279 }
280 if (entParser)
281 m_ParamValues.Add(entParser->Parse(pvalue));
282 else
283 m_ParamValues.Add(pvalue);
284 state = ST_BEFORE_NAME;
285 }
286 else
287 pvalue << c;
288 break;
289 }
290 }
291
292 #undef IS_WHITE
293 }
294 m_Begin = i;
295
296 cache->QueryTag(pos, &m_End1, &m_End2);
297 if (m_End1 > end_pos) m_End1 = end_pos;
298 if (m_End2 > end_pos) m_End2 = end_pos;
299 }
300
301 wxHtmlTag::~wxHtmlTag()
302 {
303 wxHtmlTag *t1, *t2;
304 t1 = m_FirstChild;
305 while (t1)
306 {
307 t2 = t1->GetNextSibling();
308 delete t1;
309 t1 = t2;
310 }
311 }
312
313 bool wxHtmlTag::HasParam(const wxString& par) const
314 {
315 return (m_ParamNames.Index(par, FALSE) != wxNOT_FOUND);
316 }
317
318 wxString wxHtmlTag::GetParam(const wxString& par, bool with_commas) const
319 {
320 int index = m_ParamNames.Index(par, FALSE);
321 if (index == wxNOT_FOUND)
322 return wxEmptyString;
323 if (with_commas)
324 {
325 // VS: backward compatibility, seems to be never used by wxHTML...
326 wxString s;
327 s << wxT('"') << m_ParamValues[index] << wxT('"');
328 return s;
329 }
330 else
331 return m_ParamValues[index];
332 }
333
334 int wxHtmlTag::ScanParam(const wxString& par,
335 const wxChar *format,
336 void *param) const
337 {
338 wxString parval = GetParam(par);
339 return wxSscanf(parval, format, param);
340 }
341
342 bool wxHtmlTag::GetParamAsColour(const wxString& par, wxColour *clr) const
343 {
344 wxString str = GetParam(par);
345
346 if (str.IsEmpty()) return FALSE;
347 if (str.GetChar(0) == wxT('#'))
348 {
349 unsigned long tmp;
350 if (ScanParam(par, wxT("#%lX"), &tmp) != 1)
351 return FALSE;
352 *clr = wxColour((unsigned char)((tmp & 0xFF0000) >> 16),
353 (unsigned char)((tmp & 0x00FF00) >> 8),
354 (unsigned char)(tmp & 0x0000FF));
355 return TRUE;
356 }
357 else
358 {
359 // Handle colours defined in HTML 4.0:
360 #define HTML_COLOUR(name,r,g,b) \
361 if (str.IsSameAs(wxT(name), FALSE)) \
362 { *clr = wxColour(r,g,b); return TRUE; }
363 HTML_COLOUR("black", 0x00,0x00,0x00)
364 HTML_COLOUR("silver", 0xC0,0xC0,0xC0)
365 HTML_COLOUR("gray", 0x80,0x80,0x80)
366 HTML_COLOUR("white", 0xFF,0xFF,0xFF)
367 HTML_COLOUR("maroon", 0x80,0x00,0x00)
368 HTML_COLOUR("red", 0xFF,0x00,0x00)
369 HTML_COLOUR("purple", 0x80,0x00,0x80)
370 HTML_COLOUR("fuchsia", 0xFF,0x00,0xFF)
371 HTML_COLOUR("green", 0x00,0x80,0x00)
372 HTML_COLOUR("lime", 0x00,0xFF,0x00)
373 HTML_COLOUR("olive", 0x80,0x80,0x00)
374 HTML_COLOUR("yellow", 0xFF,0xFF,0x00)
375 HTML_COLOUR("navy", 0x00,0x00,0x80)
376 HTML_COLOUR("blue", 0x00,0x00,0xFF)
377 HTML_COLOUR("teal", 0x00,0x80,0x80)
378 HTML_COLOUR("aqua", 0x00,0xFF,0xFF)
379 #undef HTML_COLOUR
380 }
381
382 return FALSE;
383 }
384
385 bool wxHtmlTag::GetParamAsInt(const wxString& par, int *clr) const
386 {
387 if (!HasParam(par)) return FALSE;
388 long i;
389 bool succ = GetParam(par).ToLong(&i);
390 *clr = (int)i;
391 return succ;
392 }
393
394 wxString wxHtmlTag::GetAllParams() const
395 {
396 // VS: this function is for backward compatiblity only,
397 // never used by wxHTML
398 wxString s;
399 size_t cnt = m_ParamNames.GetCount();
400 for (size_t i = 0; i < cnt; i++)
401 {
402 s << m_ParamNames[i];
403 s << wxT('=');
404 if (m_ParamValues[i].Find(wxT('"')) != wxNOT_FOUND)
405 s << wxT('\'') << m_ParamValues[i] << wxT('\'');
406 else
407 s << wxT('"') << m_ParamValues[i] << wxT('"');
408 }
409 return s;
410 }
411
412 wxHtmlTag *wxHtmlTag::GetFirstSibling() const
413 {
414 if (m_Parent)
415 return m_Parent->m_FirstChild;
416 else
417 {
418 wxHtmlTag *cur = (wxHtmlTag*)this;
419 while (cur->m_Prev)
420 cur = cur->m_Prev;
421 return cur;
422 }
423 }
424
425 wxHtmlTag *wxHtmlTag::GetLastSibling() const
426 {
427 if (m_Parent)
428 return m_Parent->m_LastChild;
429 else
430 {
431 wxHtmlTag *cur = (wxHtmlTag*)this;
432 while (cur->m_Next)
433 cur = cur->m_Next;
434 return cur;
435 }
436 }
437
438 wxHtmlTag *wxHtmlTag::GetNextTag() const
439 {
440 if (m_FirstChild) return m_FirstChild;
441 if (m_Next) return m_Next;
442 wxHtmlTag *cur = m_Parent;
443 if (!cur) return NULL;
444 while (cur->m_Parent && !cur->m_Next)
445 cur = cur->m_Parent;
446 return cur->m_Next;
447 }
448
449 #endif