Gitiles
Code Review Sign In
gerrit-public.fairphone.software / platform / external / python / cpython3 / 78a5271d3e79e4ee074b832629bfff9ca1c255ef / . / Lib / markupbase.py
blob: b8d8d5d27edb4f7b16e36f683d63df4c99485d06 [file] [log] [blame]
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]1"""Shared support for scanning document type declarations in HTML and XHTML."""
2
3import re
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]4
5_declname_match = re.compile(r'[a-zA-Z][-_.a-zA-Z0-9]*\s*').match
6_declstringlit_match = re.compile(r'(\'[^\']*\'|"[^"]*")\s*').match
Martin v. Löwis3163a3b2003-03-30 14:25:40 +0000[diff] [blame]7_commentclose = re.compile(r'--\s*>')
8_markedsectionclose = re.compile(r']\s*]\s*>')
9
10# An analysis of the MS-Word extensions is available at
11# http://www.planetpublish.com/xmlarena/xap/Thursday/WordtoXML.pdf
12
13_msmarkedsectionclose = re.compile(r']\s*>')
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]14
15del re
16
17
18class ParserBase:
19 """Parser base class which provides some common support methods used
20 by the SGML/HTML and XHTML parsers."""
21
Fred Drake5445f072001-10-26 18:02:28 +0000[diff] [blame]22 def __init__(self):
23 if self.__class__ is ParserBase:
24 raise RuntimeError(
25 "markupbase.ParserBase must be subclassed")
26
27 def error(self, message):
28 raise NotImplementedError(
29 "subclasses of ParserBase must override error()")
30
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]31 def reset(self):
32 self.lineno = 1
33 self.offset = 0
34
35 def getpos(self):
36 """Return current line number and offset."""
37 return self.lineno, self.offset
38
39 # Internal -- update line number and offset. This should be
40 # called for each piece of data exactly once, in order -- in other
41 # words the concatenation of all the input strings to this
42 # function should be exactly the entire input.
43 def updatepos(self, i, j):
44 if i >= j:
45 return j
46 rawdata = self.rawdata
Neal Norwitz7ce734c2002-05-31 14:13:04 +0000[diff] [blame]47 nlines = rawdata.count("\n", i, j)
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]48 if nlines:
49 self.lineno = self.lineno + nlines
Neal Norwitz7ce734c2002-05-31 14:13:04 +0000[diff] [blame]50 pos = rawdata.rindex("\n", i, j) # Should not fail
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]51 self.offset = j-(pos+1)
52 else:
53 self.offset = self.offset + j-i
54 return j
55
56 _decl_otherchars = ''
57
58 # Internal -- parse declaration (for use by subclasses).
59 def parse_declaration(self, i):
60 # This is some sort of declaration; in "HTML as
61 # deployed," this should only be the document type
62 # declaration ("<!DOCTYPE html...>").
Tim Peters0eadaac2003-04-24 16:02:54 +0000[diff] [blame]63 # ISO 8879:1986, however, has more complex
Martin v. Löwis3163a3b2003-03-30 14:25:40 +0000[diff] [blame]64 # declaration syntax for elements in <!...>, including:
65 # --comment--
66 # [marked section]
Tim Peters0eadaac2003-04-24 16:02:54 +0000[diff] [blame]67 # name in the following list: ENTITY, DOCTYPE, ELEMENT,
68 # ATTLIST, NOTATION, SHORTREF, USEMAP,
Martin v. Löwis3163a3b2003-03-30 14:25:40 +0000[diff] [blame]69 # LINKTYPE, LINK, IDLINK, USELINK, SYSTEM
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]70 rawdata = self.rawdata
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]71 j = i + 2
72 assert rawdata[i:j] == "<!", "unexpected call to parse_declaration"
73 if rawdata[j:j+1] in ("-", ""):
74 # Start of comment followed by buffer boundary,
75 # or just a buffer boundary.
76 return -1
Martin v. Löwis3163a3b2003-03-30 14:25:40 +0000[diff] [blame]77 # A simple, practical version could look like: ((name|stringlit) S*) + '>'
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]78 n = len(rawdata)
Martin v. Löwis3163a3b2003-03-30 14:25:40 +0000[diff] [blame]79 if rawdata[j:j+1] == '--': #comment
80 # Locate --.*-- as the body of the comment
81 return self.parse_comment(i)
82 elif rawdata[j] == '[': #marked section
83 # Locate [statusWord [...arbitrary SGML...]] as the body of the marked section
84 # Where statusWord is one of TEMP, CDATA, IGNORE, INCLUDE, RCDATA
85 # Note that this is extended by Microsoft Office "Save as Web" function
86 # to include [if...] and [endif].
87 return self.parse_marked_section(i)
88 else: #all other declaration elements
89 decltype, j = self._scan_name(j, i)
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]90 if j < 0:
91 return j
92 if decltype == "doctype":
93 self._decl_otherchars = ''
94 while j < n:
95 c = rawdata[j]
96 if c == ">":
97 # end of declaration syntax
98 data = rawdata[i+2:j]
99 if decltype == "doctype":
100 self.handle_decl(data)
101 else:
102 self.unknown_decl(data)
103 return j + 1
104 if c in "\"'":
105 m = _declstringlit_match(rawdata, j)
106 if not m:
107 return -1 # incomplete
108 j = m.end()
109 elif c in "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ":
110 name, j = self._scan_name(j, i)
111 elif c in self._decl_otherchars:
112 j = j + 1
113 elif c == "[":
Martin v. Löwis3163a3b2003-03-30 14:25:40 +0000[diff] [blame]114 # this could be handled in a separate doctype parser
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]115 if decltype == "doctype":
116 j = self._parse_doctype_subset(j + 1, i)
Martin v. Löwis3163a3b2003-03-30 14:25:40 +0000[diff] [blame]117 elif decltype in ("attlist", "linktype", "link", "element"):
118 # must tolerate []'d groups in a content model in an element declaration
119 # also in data attribute specifications of attlist declaration
120 # also link type declaration subsets in linktype declarations
121 # also link attribute specification lists in link declarations
122 self.error("unsupported '[' char in %s declaration" % decltype)
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]123 else:
124 self.error("unexpected '[' char in declaration")
125 else:
126 self.error(
Walter Dörwald70a6b492004-02-12 17:35:32 +0000[diff] [blame]127 "unexpected %r char in declaration" % rawdata[j])
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]128 if j < 0:
129 return j
130 return -1 # incomplete
131
Martin v. Löwis3163a3b2003-03-30 14:25:40 +0000[diff] [blame]132 # Internal -- parse a marked section
133 # Override this to handle MS-word extension syntax <![if word]>content<![endif]>
134 def parse_marked_section( self, i, report=1 ):
135 rawdata= self.rawdata
136 assert rawdata[i:i+3] == '<![', "unexpected call to parse_marked_section()"
137 sectName, j = self._scan_name( i+3, i )
138 if j < 0:
139 return j
140 if sectName in ("temp", "cdata", "ignore", "include", "rcdata"):
141 # look for standard ]]> ending
142 match= _markedsectionclose.search(rawdata, i+3)
143 elif sectName in ("if", "else", "endif"):
144 # look for MS Office ]> ending
145 match= _msmarkedsectionclose.search(rawdata, i+3)
146 else:
Walter Dörwald70a6b492004-02-12 17:35:32 +0000[diff] [blame]147 self.error('unknown status keyword %r in marked section' % rawdata[i+3:j])
Martin v. Löwis3163a3b2003-03-30 14:25:40 +0000[diff] [blame]148 if not match:
149 return -1
150 if report:
151 j = match.start(0)
152 self.unknown_decl(rawdata[i+3: j])
153 return match.end(0)
Tim Peters0eadaac2003-04-24 16:02:54 +0000[diff] [blame]154
Martin v. Löwis3163a3b2003-03-30 14:25:40 +0000[diff] [blame]155 # Internal -- parse comment, return length or -1 if not terminated
156 def parse_comment(self, i, report=1):
157 rawdata = self.rawdata
158 if rawdata[i:i+4] != '<!--':
159 self.error('unexpected call to parse_comment()')
160 match = _commentclose.search(rawdata, i+4)
161 if not match:
162 return -1
163 if report:
164 j = match.start(0)
165 self.handle_comment(rawdata[i+4: j])
166 return match.end(0)
167
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]168 # Internal -- scan past the internal subset in a <!DOCTYPE declaration,
169 # returning the index just past any whitespace following the trailing ']'.
170 def _parse_doctype_subset(self, i, declstartpos):
171 rawdata = self.rawdata
172 n = len(rawdata)
173 j = i
174 while j < n:
175 c = rawdata[j]
176 if c == "<":
177 s = rawdata[j:j+2]
178 if s == "<":
179 # end of buffer; incomplete
180 return -1
181 if s != "<!":
182 self.updatepos(declstartpos, j + 1)
Walter Dörwald70a6b492004-02-12 17:35:32 +0000[diff] [blame]183 self.error("unexpected char in internal subset (in %r)" % s)
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]184 if (j + 2) == n:
185 # end of buffer; incomplete
186 return -1
187 if (j + 4) > n:
188 # end of buffer; incomplete
189 return -1
190 if rawdata[j:j+4] == "<!--":
191 j = self.parse_comment(j, report=0)
192 if j < 0:
193 return j
194 continue
195 name, j = self._scan_name(j + 2, declstartpos)
196 if j == -1:
197 return -1
198 if name not in ("attlist", "element", "entity", "notation"):
199 self.updatepos(declstartpos, j + 2)
200 self.error(
Walter Dörwald70a6b492004-02-12 17:35:32 +0000[diff] [blame]201 "unknown declaration %r in internal subset" % name)
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]202 # handle the individual names
203 meth = getattr(self, "_parse_doctype_" + name)
204 j = meth(j, declstartpos)
205 if j < 0:
206 return j
207 elif c == "%":
208 # parameter entity reference
209 if (j + 1) == n:
210 # end of buffer; incomplete
211 return -1
212 s, j = self._scan_name(j + 1, declstartpos)
213 if j < 0:
214 return j
215 if rawdata[j] == ";":
216 j = j + 1
217 elif c == "]":
218 j = j + 1
Walter Dörwald65230a22002-06-03 15:58:32 +0000[diff] [blame]219 while j < n and rawdata[j].isspace():
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]220 j = j + 1
221 if j < n:
222 if rawdata[j] == ">":
223 return j
224 self.updatepos(declstartpos, j)
225 self.error("unexpected char after internal subset")
226 else:
227 return -1
Walter Dörwald65230a22002-06-03 15:58:32 +0000[diff] [blame]228 elif c.isspace():
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]229 j = j + 1
230 else:
231 self.updatepos(declstartpos, j)
Walter Dörwald70a6b492004-02-12 17:35:32 +0000[diff] [blame]232 self.error("unexpected char %r in internal subset" % c)
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]233 # end of buffer reached
234 return -1
235
236 # Internal -- scan past <!ELEMENT declarations
237 def _parse_doctype_element(self, i, declstartpos):
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]238 name, j = self._scan_name(i, declstartpos)
239 if j == -1:
240 return -1
241 # style content model; just skip until '>'
Fred Drake5445f072001-10-26 18:02:28 +0000[diff] [blame]242 rawdata = self.rawdata
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]243 if '>' in rawdata[j:]:
Neal Norwitz7ce734c2002-05-31 14:13:04 +0000[diff] [blame]244 return rawdata.find(">", j) + 1
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]245 return -1
246
247 # Internal -- scan past <!ATTLIST declarations
248 def _parse_doctype_attlist(self, i, declstartpos):
249 rawdata = self.rawdata
250 name, j = self._scan_name(i, declstartpos)
251 c = rawdata[j:j+1]
252 if c == "":
253 return -1
254 if c == ">":
255 return j + 1
256 while 1:
257 # scan a series of attribute descriptions; simplified:
258 # name type [value] [#constraint]
259 name, j = self._scan_name(j, declstartpos)
260 if j < 0:
261 return j
262 c = rawdata[j:j+1]
263 if c == "":
264 return -1
265 if c == "(":
266 # an enumerated type; look for ')'
267 if ")" in rawdata[j:]:
Neal Norwitz7ce734c2002-05-31 14:13:04 +0000[diff] [blame]268 j = rawdata.find(")", j) + 1
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]269 else:
270 return -1
Walter Dörwald65230a22002-06-03 15:58:32 +0000[diff] [blame]271 while rawdata[j:j+1].isspace():
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]272 j = j + 1
273 if not rawdata[j:]:
274 # end of buffer, incomplete
275 return -1
276 else:
277 name, j = self._scan_name(j, declstartpos)
278 c = rawdata[j:j+1]
279 if not c:
280 return -1
281 if c in "'\"":
282 m = _declstringlit_match(rawdata, j)
283 if m:
284 j = m.end()
285 else:
286 return -1
287 c = rawdata[j:j+1]
288 if not c:
289 return -1
290 if c == "#":
291 if rawdata[j:] == "#":
292 # end of buffer
293 return -1
294 name, j = self._scan_name(j + 1, declstartpos)
295 if j < 0:
296 return j
297 c = rawdata[j:j+1]
298 if not c:
299 return -1
300 if c == '>':
301 # all done
302 return j + 1
303
304 # Internal -- scan past <!NOTATION declarations
305 def _parse_doctype_notation(self, i, declstartpos):
306 name, j = self._scan_name(i, declstartpos)
307 if j < 0:
308 return j
309 rawdata = self.rawdata
310 while 1:
311 c = rawdata[j:j+1]
312 if not c:
313 # end of buffer; incomplete
314 return -1
315 if c == '>':
316 return j + 1
317 if c in "'\"":
318 m = _declstringlit_match(rawdata, j)
319 if not m:
320 return -1
321 j = m.end()
322 else:
323 name, j = self._scan_name(j, declstartpos)
324 if j < 0:
325 return j
326
327 # Internal -- scan past <!ENTITY declarations
328 def _parse_doctype_entity(self, i, declstartpos):
329 rawdata = self.rawdata
330 if rawdata[i:i+1] == "%":
331 j = i + 1
332 while 1:
333 c = rawdata[j:j+1]
334 if not c:
335 return -1
Walter Dörwald65230a22002-06-03 15:58:32 +0000[diff] [blame]336 if c.isspace():
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]337 j = j + 1
338 else:
339 break
340 else:
341 j = i
342 name, j = self._scan_name(j, declstartpos)
343 if j < 0:
344 return j
345 while 1:
346 c = self.rawdata[j:j+1]
347 if not c:
348 return -1
349 if c in "'\"":
350 m = _declstringlit_match(rawdata, j)
351 if m:
352 j = m.end()
353 else:
354 return -1 # incomplete
355 elif c == ">":
356 return j + 1
357 else:
358 name, j = self._scan_name(j, declstartpos)
359 if j < 0:
360 return j
361
362 # Internal -- scan a name token and the new position and the token, or
363 # return -1 if we've reached the end of the buffer.
364 def _scan_name(self, i, declstartpos):
365 rawdata = self.rawdata
366 n = len(rawdata)
367 if i == n:
368 return None, -1
369 m = _declname_match(rawdata, i)
370 if m:
371 s = m.group()
372 name = s.strip()
373 if (i + len(s)) == n:
374 return None, -1 # end of buffer
Neal Norwitz7ce734c2002-05-31 14:13:04 +0000[diff] [blame]375 return name.lower(), m.end()
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]376 else:
377 self.updatepos(declstartpos, i)
Andrew M. Kuchlingf027ca82004-07-10 21:49:45 +0000[diff] [blame]378 self.error("expected name token at %r"
379 % rawdata[declstartpos:declstartpos+20])
Fred Drake5445f072001-10-26 18:02:28 +0000[diff] [blame]380
381 # To be overridden -- handlers for unknown objects
382 def unknown_decl(self, data):
383 pass