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gerrit-public.fairphone.software / platform / external / python / cpython3 / b5aa407196b68b807c19cfecbdfc57cdb647de68 / . / Lib / markupbase.py
blob: 62587e0883e77e6ed2094938d1ff7083ed7f1f84 [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(
127 "unexpected %s char in declaration" % `rawdata[j]`)
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:
147 self.error('unknown status keyword %s in marked section' % `rawdata[i+3:j]`)
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)
183 self.error("unexpected char in internal subset (in %s)"
184 % `s`)
185 if (j + 2) == n:
186 # end of buffer; incomplete
187 return -1
188 if (j + 4) > n:
189 # end of buffer; incomplete
190 return -1
191 if rawdata[j:j+4] == "<!--":
192 j = self.parse_comment(j, report=0)
193 if j < 0:
194 return j
195 continue
196 name, j = self._scan_name(j + 2, declstartpos)
197 if j == -1:
198 return -1
199 if name not in ("attlist", "element", "entity", "notation"):
200 self.updatepos(declstartpos, j + 2)
201 self.error(
202 "unknown declaration %s in internal subset" % `name`)
203 # handle the individual names
204 meth = getattr(self, "_parse_doctype_" + name)
205 j = meth(j, declstartpos)
206 if j < 0:
207 return j
208 elif c == "%":
209 # parameter entity reference
210 if (j + 1) == n:
211 # end of buffer; incomplete
212 return -1
213 s, j = self._scan_name(j + 1, declstartpos)
214 if j < 0:
215 return j
216 if rawdata[j] == ";":
217 j = j + 1
218 elif c == "]":
219 j = j + 1
Walter Dörwald65230a22002-06-03 15:58:32 +0000[diff] [blame]220 while j < n and rawdata[j].isspace():
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]221 j = j + 1
222 if j < n:
223 if rawdata[j] == ">":
224 return j
225 self.updatepos(declstartpos, j)
226 self.error("unexpected char after internal subset")
227 else:
228 return -1
Walter Dörwald65230a22002-06-03 15:58:32 +0000[diff] [blame]229 elif c.isspace():
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]230 j = j + 1
231 else:
232 self.updatepos(declstartpos, j)
233 self.error("unexpected char %s in internal subset" % `c`)
234 # end of buffer reached
235 return -1
236
237 # Internal -- scan past <!ELEMENT declarations
238 def _parse_doctype_element(self, i, declstartpos):
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]239 name, j = self._scan_name(i, declstartpos)
240 if j == -1:
241 return -1
242 # style content model; just skip until '>'
Fred Drake5445f072001-10-26 18:02:28 +0000[diff] [blame]243 rawdata = self.rawdata
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]244 if '>' in rawdata[j:]:
Neal Norwitz7ce734c2002-05-31 14:13:04 +0000[diff] [blame]245 return rawdata.find(">", j) + 1
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]246 return -1
247
248 # Internal -- scan past <!ATTLIST declarations
249 def _parse_doctype_attlist(self, i, declstartpos):
250 rawdata = self.rawdata
251 name, j = self._scan_name(i, declstartpos)
252 c = rawdata[j:j+1]
253 if c == "":
254 return -1
255 if c == ">":
256 return j + 1
257 while 1:
258 # scan a series of attribute descriptions; simplified:
259 # name type [value] [#constraint]
260 name, j = self._scan_name(j, declstartpos)
261 if j < 0:
262 return j
263 c = rawdata[j:j+1]
264 if c == "":
265 return -1
266 if c == "(":
267 # an enumerated type; look for ')'
268 if ")" in rawdata[j:]:
Neal Norwitz7ce734c2002-05-31 14:13:04 +0000[diff] [blame]269 j = rawdata.find(")", j) + 1
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]270 else:
271 return -1
Walter Dörwald65230a22002-06-03 15:58:32 +0000[diff] [blame]272 while rawdata[j:j+1].isspace():
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]273 j = j + 1
274 if not rawdata[j:]:
275 # end of buffer, incomplete
276 return -1
277 else:
278 name, j = self._scan_name(j, declstartpos)
279 c = rawdata[j:j+1]
280 if not c:
281 return -1
282 if c in "'\"":
283 m = _declstringlit_match(rawdata, j)
284 if m:
285 j = m.end()
286 else:
287 return -1
288 c = rawdata[j:j+1]
289 if not c:
290 return -1
291 if c == "#":
292 if rawdata[j:] == "#":
293 # end of buffer
294 return -1
295 name, j = self._scan_name(j + 1, declstartpos)
296 if j < 0:
297 return j
298 c = rawdata[j:j+1]
299 if not c:
300 return -1
301 if c == '>':
302 # all done
303 return j + 1
304
305 # Internal -- scan past <!NOTATION declarations
306 def _parse_doctype_notation(self, i, declstartpos):
307 name, j = self._scan_name(i, declstartpos)
308 if j < 0:
309 return j
310 rawdata = self.rawdata
311 while 1:
312 c = rawdata[j:j+1]
313 if not c:
314 # end of buffer; incomplete
315 return -1
316 if c == '>':
317 return j + 1
318 if c in "'\"":
319 m = _declstringlit_match(rawdata, j)
320 if not m:
321 return -1
322 j = m.end()
323 else:
324 name, j = self._scan_name(j, declstartpos)
325 if j < 0:
326 return j
327
328 # Internal -- scan past <!ENTITY declarations
329 def _parse_doctype_entity(self, i, declstartpos):
330 rawdata = self.rawdata
331 if rawdata[i:i+1] == "%":
332 j = i + 1
333 while 1:
334 c = rawdata[j:j+1]
335 if not c:
336 return -1
Walter Dörwald65230a22002-06-03 15:58:32 +0000[diff] [blame]337 if c.isspace():
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]338 j = j + 1
339 else:
340 break
341 else:
342 j = i
343 name, j = self._scan_name(j, declstartpos)
344 if j < 0:
345 return j
346 while 1:
347 c = self.rawdata[j:j+1]
348 if not c:
349 return -1
350 if c in "'\"":
351 m = _declstringlit_match(rawdata, j)
352 if m:
353 j = m.end()
354 else:
355 return -1 # incomplete
356 elif c == ">":
357 return j + 1
358 else:
359 name, j = self._scan_name(j, declstartpos)
360 if j < 0:
361 return j
362
363 # Internal -- scan a name token and the new position and the token, or
364 # return -1 if we've reached the end of the buffer.
365 def _scan_name(self, i, declstartpos):
366 rawdata = self.rawdata
367 n = len(rawdata)
368 if i == n:
369 return None, -1
370 m = _declname_match(rawdata, i)
371 if m:
372 s = m.group()
373 name = s.strip()
374 if (i + len(s)) == n:
375 return None, -1 # end of buffer
Neal Norwitz7ce734c2002-05-31 14:13:04 +0000[diff] [blame]376 return name.lower(), m.end()
Fred Drake68f8a802001-09-24 20:01:28 +0000[diff] [blame]377 else:
378 self.updatepos(declstartpos, i)
Fred Drake3d32be12001-10-13 15:59:47 +0000[diff] [blame]379 self.error("expected name token")
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