Tom Tromey <tromey at redhat.com>
[emacs.git] / lisp / xml.el
blobf2bcf86b5e7d37e86680c125328045bedfb0d12c
1 ;;; xml.el --- XML parser
3 ;; Copyright (C) 2000, 2001, 2002, 2003, 2004,
4 ;; 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
6 ;; Author: Emmanuel Briot <briot@gnat.com>
7 ;; Maintainer: Mark A. Hershberger <mah@everybody.org>
8 ;; Keywords: xml, data
10 ;; This file is part of GNU Emacs.
12 ;; GNU Emacs is free software; you can redistribute it and/or modify
13 ;; it under the terms of the GNU General Public License as published by
14 ;; the Free Software Foundation; either version 3, or (at your option)
15 ;; any later version.
17 ;; GNU Emacs is distributed in the hope that it will be useful,
18 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
19 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 ;; GNU General Public License for more details.
22 ;; You should have received a copy of the GNU General Public License
23 ;; along with GNU Emacs; see the file COPYING. If not, write to the
24 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
25 ;; Boston, MA 02110-1301, USA.
27 ;;; Commentary:
29 ;; This file contains a somewhat incomplete non-validating XML parser. It
30 ;; parses a file, and returns a list that can be used internally by
31 ;; any other Lisp libraries.
33 ;;; FILE FORMAT
35 ;; The document type declaration may either be ignored or (optionally)
36 ;; parsed, but currently the parsing will only accept element
37 ;; declarations. The XML file is assumed to be well-formed. In case
38 ;; of error, the parsing stops and the XML file is shown where the
39 ;; parsing stopped.
41 ;; It also knows how to ignore comments and processing instructions.
43 ;; The XML file should have the following format:
44 ;; <node1 attr1="name1" attr2="name2" ...>value
45 ;; <node2 attr3="name3" attr4="name4">value2</node2>
46 ;; <node3 attr5="name5" attr6="name6">value3</node3>
47 ;; </node1>
48 ;; Of course, the name of the nodes and attributes can be anything. There can
49 ;; be any number of attributes (or none), as well as any number of children
50 ;; below the nodes.
52 ;; There can be only top level node, but with any number of children below.
54 ;;; LIST FORMAT
56 ;; The functions `xml-parse-file', `xml-parse-region' and
57 ;; `xml-parse-tag' return a list with the following format:
59 ;; xml-list ::= (node node ...)
60 ;; node ::= (qname attribute-list . child_node_list)
61 ;; child_node_list ::= child_node child_node ...
62 ;; child_node ::= node | string
63 ;; qname ::= (:namespace-uri . "name") | "name"
64 ;; attribute_list ::= ((qname . "value") (qname . "value") ...)
65 ;; | nil
66 ;; string ::= "..."
68 ;; Some macros are provided to ease the parsing of this list.
69 ;; Whitespace is preserved. Fixme: There should be a tree-walker that
70 ;; can remove it.
72 ;; TODO:
73 ;; * xml:base, xml:space support
74 ;; * more complete DOCTYPE parsing
75 ;; * pi support
77 ;;; Code:
79 ;; Note that buffer-substring and match-string were formerly used in
80 ;; several places, because the -no-properties variants remove
81 ;; composition info. However, after some discussion on emacs-devel,
82 ;; the consensus was that the speed of the -no-properties variants was
83 ;; a worthwhile tradeoff especially since we're usually parsing files
84 ;; instead of hand-crafted XML.
86 ;;*******************************************************************
87 ;;**
88 ;;** Macros to parse the list
89 ;;**
90 ;;*******************************************************************
92 (defconst xml-undefined-entity "?"
93 "What to substitute for undefined entities")
95 (defvar xml-entity-alist
96 '(("lt" . "<")
97 ("gt" . ">")
98 ("apos" . "'")
99 ("quot" . "\"")
100 ("amp" . "&"))
101 "The defined entities. Entities are added to this when the DTD is parsed.")
103 (defvar xml-sub-parser nil
104 "Dynamically set this to a non-nil value if you want to parse an XML fragment.")
106 (defvar xml-validating-parser nil
107 "Set to non-nil to get validity checking.")
109 (defsubst xml-node-name (node)
110 "Return the tag associated with NODE.
111 Without namespace-aware parsing, the tag is a symbol.
113 With namespace-aware parsing, the tag is a cons of a string
114 representing the uri of the namespace with the local name of the
115 tag. For example,
117 <foo>
119 would be represented by
121 '(\"\" . \"foo\")."
123 (car node))
125 (defsubst xml-node-attributes (node)
126 "Return the list of attributes of NODE.
127 The list can be nil."
128 (nth 1 node))
130 (defsubst xml-node-children (node)
131 "Return the list of children of NODE.
132 This is a list of nodes, and it can be nil."
133 (cddr node))
135 (defun xml-get-children (node child-name)
136 "Return the children of NODE whose tag is CHILD-NAME.
137 CHILD-NAME should match the value returned by `xml-node-name'."
138 (let ((match ()))
139 (dolist (child (xml-node-children node))
140 (if (and (listp child)
141 (equal (xml-node-name child) child-name))
142 (push child match)))
143 (nreverse match)))
145 (defun xml-get-attribute-or-nil (node attribute)
146 "Get from NODE the value of ATTRIBUTE.
147 Return nil if the attribute was not found.
149 See also `xml-get-attribute'."
150 (cdr (assoc attribute (xml-node-attributes node))))
152 (defsubst xml-get-attribute (node attribute)
153 "Get from NODE the value of ATTRIBUTE.
154 An empty string is returned if the attribute was not found.
156 See also `xml-get-attribute-or-nil'."
157 (or (xml-get-attribute-or-nil node attribute) ""))
159 ;;*******************************************************************
160 ;;**
161 ;;** Creating the list
162 ;;**
163 ;;*******************************************************************
165 ;;;###autoload
166 (defun xml-parse-file (file &optional parse-dtd parse-ns)
167 "Parse the well-formed XML file FILE.
168 If FILE is already visited, use its buffer and don't kill it.
169 Returns the top node with all its children.
170 If PARSE-DTD is non-nil, the DTD is parsed rather than skipped.
171 If PARSE-NS is non-nil, then QNAMES are expanded."
172 (if (get-file-buffer file)
173 (with-current-buffer (get-file-buffer file)
174 (save-excursion
175 (xml-parse-region (point-min)
176 (point-max)
177 (current-buffer)
178 parse-dtd parse-ns)))
179 (with-temp-buffer
180 (insert-file-contents file)
181 (xml-parse-region (point-min)
182 (point-max)
183 (current-buffer)
184 parse-dtd parse-ns))))
187 (defvar xml-name-re)
188 (defvar xml-entity-value-re)
189 (defvar xml-att-def-re)
190 (let* ((start-chars (concat "[:alpha:]:_"))
191 (name-chars (concat "-[:digit:]." start-chars))
192 ;;[3] S ::= (#x20 | #x9 | #xD | #xA)+
193 (whitespace "[ \t\n\r]"))
194 ;;[4] NameStartChar ::= ":" | [A-Z] | "_" | [a-z] | [#xC0-#xD6]
195 ;; | [#xD8-#xF6] | [#xF8-#x2FF] | [#x370-#x37D] | [#x37F-#x1FFF]
196 ;; | [#x200C-#x200D] | [#x2070-#x218F] | [#x2C00-#x2FEF] | [#x3001-#xD7FF]
197 ;; | [#xF900-#xFDCF] | [#xFDF0-#xFFFD] | [#x10000-#xEFFFF]
198 (defvar xml-name-start-char-re (concat "[" start-chars "]"))
199 ;;[4a] NameChar ::= NameStartChar | "-" | "." | [0-9] | #xB7 | [#x0300-#x036F] | [#x203F-#x2040]
200 (defvar xml-name-char-re (concat "[" name-chars "]"))
201 ;;[5] Name ::= NameStartChar (NameChar)*
202 (defvar xml-name-re (concat xml-name-start-char-re xml-name-char-re "*"))
203 ;;[6] Names ::= Name (#x20 Name)*
204 (defvar xml-names-re (concat xml-name-re "\\(?: " xml-name-re "\\)*"))
205 ;;[7] Nmtoken ::= (NameChar)+
206 (defvar xml-nmtoken-re (concat xml-name-char-re "+"))
207 ;;[8] Nmtokens ::= Nmtoken (#x20 Nmtoken)*
208 (defvar xml-nmtokens-re (concat xml-nmtoken-re "\\(?: " xml-name-re "\\)*"))
209 ;;[66] CharRef ::= '&#' [0-9]+ ';' | '&#x' [0-9a-fA-F]+ ';'
210 (defvar xml-char-ref-re "\\(?:&#[0-9]+;\\|&#x[0-9a-fA-F]+;\\)")
211 ;;[68] EntityRef ::= '&' Name ';'
212 (defvar xml-entity-ref (concat "&" xml-name-re ";"))
213 ;;[69] PEReference ::= '%' Name ';'
214 (defvar xml-pe-reference-re (concat "%" xml-name-re ";"))
215 ;;[67] Reference ::= EntityRef | CharRef
216 (defvar xml-reference-re (concat "\\(?:" xml-entity-ref "\\|" xml-char-ref-re "\\)"))
217 ;;[10] AttValue ::= '"' ([^<&"] | Reference)* '"' | "'" ([^<&'] | Reference)* "'"
218 (defvar xml-att-value-re (concat "\\(?:\"\\(?:[^&\"]\\|" xml-reference-re "\\)*\"\\|"
219 "'\\(?:[^&']\\|" xml-reference-re "\\)*'\\)"))
220 ;;[56] TokenizedType ::= 'ID' [VC: ID] [VC: One ID per Element Type] [VC: ID Attribute Default]
221 ;; | 'IDREF' [VC: IDREF]
222 ;; | 'IDREFS' [VC: IDREF]
223 ;; | 'ENTITY' [VC: Entity Name]
224 ;; | 'ENTITIES' [VC: Entity Name]
225 ;; | 'NMTOKEN' [VC: Name Token]
226 ;; | 'NMTOKENS' [VC: Name Token]
227 (defvar xml-tokenized-type-re "\\(?:ID\\|IDREF\\|IDREFS\\|ENTITY\\|ENTITIES\\|NMTOKEN\\|NMTOKENS\\)")
228 ;;[58] NotationType ::= 'NOTATION' S '(' S? Name (S? '|' S? Name)* S? ')'
229 (defvar xml-notation-type-re (concat "\\(?:NOTATION" whitespace "(" whitespace "*" xml-name-re
230 "\\(?:" whitespace "*|" whitespace "*" xml-name-re "\\)*" whitespace "*)\\)"))
231 ;;[59] Enumeration ::= '(' S? Nmtoken (S? '|' S? Nmtoken)* S? ')' [VC: Enumeration] [VC: No Duplicate Tokens]
232 (defvar xml-enumeration-re (concat "\\(?:(" whitespace "*" xml-nmtoken-re
233 "\\(?:" whitespace "*|" whitespace "*" xml-nmtoken-re "\\)*"
234 whitespace ")\\)"))
235 ;;[57] EnumeratedType ::= NotationType | Enumeration
236 (defvar xml-enumerated-type-re (concat "\\(?:" xml-notation-type-re "\\|" xml-enumeration-re "\\)"))
237 ;;[54] AttType ::= StringType | TokenizedType | EnumeratedType
238 ;;[55] StringType ::= 'CDATA'
239 (defvar xml-att-type-re (concat "\\(?:CDATA\\|" xml-tokenized-type-re "\\|" xml-notation-type-re"\\|" xml-enumerated-type-re "\\)"))
240 ;;[60] DefaultDecl ::= '#REQUIRED' | '#IMPLIED' | (('#FIXED' S)? AttValue)
241 (defvar xml-default-decl-re (concat "\\(?:#REQUIRED\\|#IMPLIED\\|\\(?:#FIXED" whitespace "\\)*" xml-att-value-re "\\)"))
242 ;;[53] AttDef ::= S Name S AttType S DefaultDecl
243 (defvar xml-att-def-re (concat "\\(?:" whitespace "*" xml-name-re
244 whitespace "*" xml-att-type-re
245 whitespace "*" xml-default-decl-re "\\)"))
246 ;;[9] EntityValue ::= '"' ([^%&"] | PEReference | Reference)* '"'
247 ;; | "'" ([^%&'] | PEReference | Reference)* "'"
248 (defvar xml-entity-value-re (concat "\\(?:\"\\(?:[^%&\"]\\|" xml-pe-reference-re
249 "\\|" xml-reference-re "\\)*\"\\|'\\(?:[^%&']\\|"
250 xml-pe-reference-re "\\|" xml-reference-re "\\)*'\\)")))
251 ;;[75] ExternalID ::= 'SYSTEM' S SystemLiteral
252 ;; | 'PUBLIC' S PubidLiteral S SystemLiteral
253 ;;[76] NDataDecl ::= S 'NDATA' S
254 ;;[73] EntityDef ::= EntityValue| (ExternalID NDataDecl?)
255 ;;[71] GEDecl ::= '<!ENTITY' S Name S EntityDef S? '>'
256 ;;[74] PEDef ::= EntityValue | ExternalID
257 ;;[72] PEDecl ::= '<!ENTITY' S '%' S Name S PEDef S? '>'
258 ;;[70] EntityDecl ::= GEDecl | PEDecl
260 ;; Note that this is setup so that we can do whitespace-skipping with
261 ;; `(skip-syntax-forward " ")', inter alia. Previously this was slow
262 ;; compared with `re-search-forward', but that has been fixed. Also
263 ;; note that the standard syntax table contains other characters with
264 ;; whitespace syntax, like NBSP, but they are invalid in contexts in
265 ;; which we might skip whitespace -- specifically, they're not
266 ;; NameChars [XML 4].
268 (defvar xml-syntax-table
269 (let ((table (make-syntax-table)))
270 ;; Get space syntax correct per XML [3].
271 (dotimes (c 31)
272 (modify-syntax-entry c "." table)) ; all are space in standard table
273 (dolist (c '(?\t ?\n ?\r)) ; these should be space
274 (modify-syntax-entry c " " table))
275 ;; For skipping attributes.
276 (modify-syntax-entry ?\" "\"" table)
277 (modify-syntax-entry ?' "\"" table)
278 ;; Non-alnum name chars should be symbol constituents (`-' and `_'
279 ;; are OK by default).
280 (modify-syntax-entry ?. "_" table)
281 (modify-syntax-entry ?: "_" table)
282 ;; XML [89]
283 (unless (featurep 'xemacs)
284 (dolist (c '(#x00B7 #x02D0 #x02D1 #x0387 #x0640 #x0E46 #x0EC6 #x3005
285 #x3031 #x3032 #x3033 #x3034 #x3035 #x309D #x309E #x30FC
286 #x30FD #x30FE))
287 (modify-syntax-entry (decode-char 'ucs c) "w" table)))
288 ;; Fixme: rest of [4]
289 table)
290 "Syntax table used by `xml-parse-region'.")
292 ;; XML [5]
293 ;; Note that [:alpha:] matches all multibyte chars with word syntax.
294 (eval-and-compile
295 (defconst xml-name-regexp "[[:alpha:]_:][[:alnum:]._:-]*"))
297 ;; Fixme: This needs re-writing to deal with the XML grammar properly, i.e.
298 ;; document ::= prolog element Misc*
299 ;; prolog ::= XMLDecl? Misc* (doctypedecl Misc*)?
301 ;;;###autoload
302 (defun xml-parse-region (beg end &optional buffer parse-dtd parse-ns)
303 "Parse the region from BEG to END in BUFFER.
304 If BUFFER is nil, it defaults to the current buffer.
305 Returns the XML list for the region, or raises an error if the region
306 is not well-formed XML.
307 If PARSE-DTD is non-nil, the DTD is parsed rather than skipped,
308 and returned as the first element of the list.
309 If PARSE-NS is non-nil, then QNAMES are expanded."
310 ;; Use fixed syntax table to ensure regexp char classes and syntax
311 ;; specs DTRT.
312 (with-syntax-table (standard-syntax-table)
313 (let ((case-fold-search nil) ; XML is case-sensitive.
314 xml result dtd)
315 (save-excursion
316 (if buffer
317 (set-buffer buffer))
318 (save-restriction
319 (narrow-to-region beg end)
320 (goto-char (point-min))
321 (while (not (eobp))
322 (if (search-forward "<" nil t)
323 (progn
324 (forward-char -1)
325 (setq result (xml-parse-tag parse-dtd parse-ns))
326 (if (and xml result (not xml-sub-parser))
327 ;; translation of rule [1] of XML specifications
328 (error "XML: (Not Well-Formed) Only one root tag allowed")
329 (cond
330 ((null result))
331 ((and (listp (car result))
332 parse-dtd)
333 (setq dtd (car result))
334 (if (cdr result) ; possible leading comment
335 (add-to-list 'xml (cdr result))))
337 (add-to-list 'xml result)))))
338 (goto-char (point-max))))
339 (if parse-dtd
340 (cons dtd (nreverse xml))
341 (nreverse xml)))))))
343 (defun xml-maybe-do-ns (name default xml-ns)
344 "Perform any namespace expansion.
345 NAME is the name to perform the expansion on.
346 DEFAULT is the default namespace. XML-NS is a cons of namespace
347 names to uris. When namespace-aware parsing is off, then XML-NS
348 is nil.
350 During namespace-aware parsing, any name without a namespace is
351 put into the namespace identified by DEFAULT. nil is used to
352 specify that the name shouldn't be given a namespace."
353 (if (consp xml-ns)
354 (let* ((nsp (string-match ":" name))
355 (lname (if nsp (substring name (match-end 0)) name))
356 (prefix (if nsp (substring name 0 (match-beginning 0)) default))
357 (special (and (string-equal lname "xmlns") (not prefix)))
358 ;; Setting default to nil will insure that there is not
359 ;; matching cons in xml-ns. In which case we
360 (ns (or (cdr (assoc (if special "xmlns" prefix)
361 xml-ns))
362 "")))
363 (cons ns (if special "" lname)))
364 (intern name)))
366 (defun xml-parse-fragment (&optional parse-dtd parse-ns)
367 "Parse xml-like fragments."
368 (let ((xml-sub-parser t)
369 children)
370 (while (not (eobp))
371 (let ((bit (xml-parse-tag
372 parse-dtd parse-ns)))
373 (if children
374 (setq children (append (list bit) children))
375 (if (stringp bit)
376 (setq children (list bit))
377 (setq children bit)))))
378 (reverse children)))
380 (defun xml-parse-tag (&optional parse-dtd parse-ns)
381 "Parse the tag at point.
382 If PARSE-DTD is non-nil, the DTD of the document, if any, is parsed and
383 returned as the first element in the list.
384 If PARSE-NS is non-nil, then QNAMES are expanded.
385 Returns one of:
386 - a list : the matching node
387 - nil : the point is not looking at a tag.
388 - a pair : the first element is the DTD, the second is the node."
389 (let ((xml-validating-parser (or parse-dtd xml-validating-parser))
390 (xml-ns (if (consp parse-ns)
391 parse-ns
392 (if parse-ns
393 (list
394 ;; Default for empty prefix is no namespace
395 (cons "" "")
396 ;; "xml" namespace
397 (cons "xml" "http://www.w3.org/XML/1998/namespace")
398 ;; We need to seed the xmlns namespace
399 (cons "xmlns" "http://www.w3.org/2000/xmlns/"))))))
400 (cond
401 ;; Processing instructions (like the <?xml version="1.0"?> tag at the
402 ;; beginning of a document).
403 ((looking-at "<\\?")
404 (search-forward "?>")
405 (skip-syntax-forward " ")
406 (xml-parse-tag parse-dtd xml-ns))
407 ;; Character data (CDATA) sections, in which no tag should be interpreted
408 ((looking-at "<!\\[CDATA\\[")
409 (let ((pos (match-end 0)))
410 (unless (search-forward "]]>" nil t)
411 (error "XML: (Not Well Formed) CDATA section does not end anywhere in the document"))
412 (concat
413 (buffer-substring-no-properties pos (match-beginning 0))
414 (xml-parse-string))))
415 ;; DTD for the document
416 ((looking-at "<!DOCTYPE")
417 (let ((dtd (xml-parse-dtd parse-ns)))
418 (skip-syntax-forward " ")
419 (if xml-validating-parser
420 (cons dtd (xml-parse-tag nil xml-ns))
421 (xml-parse-tag nil xml-ns))))
422 ;; skip comments
423 ((looking-at "<!--")
424 (search-forward "-->")
425 nil)
426 ;; end tag
427 ((looking-at "</")
428 '())
429 ;; opening tag
430 ((looking-at "<\\([^/>[:space:]]+\\)")
431 (goto-char (match-end 1))
433 ;; Parse this node
434 (let* ((node-name (match-string-no-properties 1))
435 ;; Parse the attribute list.
436 (attrs (xml-parse-attlist xml-ns))
437 children pos)
439 ;; add the xmlns:* attrs to our cache
440 (when (consp xml-ns)
441 (dolist (attr attrs)
442 (when (and (consp (car attr))
443 (equal "http://www.w3.org/2000/xmlns/"
444 (caar attr)))
445 (push (cons (cdar attr) (cdr attr))
446 xml-ns))))
448 (setq children (list attrs (xml-maybe-do-ns node-name "" xml-ns)))
450 ;; is this an empty element ?
451 (if (looking-at "/>")
452 (progn
453 (forward-char 2)
454 (nreverse children))
456 ;; is this a valid start tag ?
457 (if (eq (char-after) ?>)
458 (progn
459 (forward-char 1)
460 ;; Now check that we have the right end-tag. Note that this
461 ;; one might contain spaces after the tag name
462 (let ((end (concat "</" node-name "\\s-*>")))
463 (while (not (looking-at end))
464 (cond
465 ((looking-at "</")
466 (error "XML: (Not Well-Formed) Invalid end tag (expecting %s) at pos %d"
467 node-name (point)))
468 ((= (char-after) ?<)
469 (let ((tag (xml-parse-tag nil xml-ns)))
470 (when tag
471 (push tag children))))
473 (let ((expansion (xml-parse-string)))
474 (setq children
475 (if (stringp expansion)
476 (if (stringp (car children))
477 ;; The two strings were separated by a comment.
478 (setq children (append (list (concat (car children) expansion))
479 (cdr children)))
480 (setq children (append (list expansion) children)))
481 (setq children (append expansion children))))))))
483 (goto-char (match-end 0))
484 (nreverse children)))
485 ;; This was an invalid start tag (Expected ">", but didn't see it.)
486 (error "XML: (Well-Formed) Couldn't parse tag: %s"
487 (buffer-substring-no-properties (- (point) 10) (+ (point) 1)))))))
488 (t ;; (Not one of PI, CDATA, Comment, End tag, or Start tag)
489 (unless xml-sub-parser ; Usually, we error out.
490 (error "XML: (Well-Formed) Invalid character"))
492 ;; However, if we're parsing incrementally, then we need to deal
493 ;; with stray CDATA.
494 (xml-parse-string)))))
496 (defun xml-parse-string ()
497 "Parse the next whatever. Could be a string, or an element."
498 (let* ((pos (point))
499 (string (progn (if (search-forward "<" nil t)
500 (forward-char -1)
501 (goto-char (point-max)))
502 (buffer-substring-no-properties pos (point)))))
503 ;; Clean up the string. As per XML specifications, the XML
504 ;; processor should always pass the whole string to the
505 ;; application. But \r's should be replaced:
506 ;; http://www.w3.org/TR/2000/REC-xml-20001006#sec-line-ends
507 (setq pos 0)
508 (while (string-match "\r\n?" string pos)
509 (setq string (replace-match "\n" t t string))
510 (setq pos (1+ (match-beginning 0))))
512 (xml-substitute-special string)))
514 (defun xml-parse-attlist (&optional xml-ns)
515 "Return the attribute-list after point.
516 Leave point at the first non-blank character after the tag."
517 (let ((attlist ())
518 end-pos name)
519 (skip-syntax-forward " ")
520 (while (looking-at (eval-when-compile
521 (concat "\\(" xml-name-regexp "\\)\\s-*=\\s-*")))
522 (setq end-pos (match-end 0))
523 (setq name (xml-maybe-do-ns (match-string-no-properties 1) nil xml-ns))
524 (goto-char end-pos)
526 ;; See also: http://www.w3.org/TR/2000/REC-xml-20001006#AVNormalize
528 ;; Do we have a string between quotes (or double-quotes),
529 ;; or a simple word ?
530 (if (looking-at "\"\\([^\"]*\\)\"")
531 (setq end-pos (match-end 0))
532 (if (looking-at "'\\([^']*\\)'")
533 (setq end-pos (match-end 0))
534 (error "XML: (Not Well-Formed) Attribute values must be given between quotes")))
536 ;; Each attribute must be unique within a given element
537 (if (assoc name attlist)
538 (error "XML: (Not Well-Formed) Each attribute must be unique within an element"))
540 ;; Multiple whitespace characters should be replaced with a single one
541 ;; in the attributes
542 (let ((string (match-string-no-properties 1))
543 (pos 0))
544 (replace-regexp-in-string "\\s-\\{2,\\}" " " string)
545 (let ((expansion (xml-substitute-special string)))
546 (unless (stringp expansion)
547 ; We say this is the constraint. It is acctually that
548 ; external entities nor "<" can be in an attribute value.
549 (error "XML: (Not Well-Formed) Entities in attributes cannot expand into elements"))
550 (push (cons name expansion) attlist)))
552 (goto-char end-pos)
553 (skip-syntax-forward " "))
554 (nreverse attlist)))
556 ;;*******************************************************************
557 ;;**
558 ;;** The DTD (document type declaration)
559 ;;** The following functions know how to skip or parse the DTD of
560 ;;** a document
561 ;;**
562 ;;*******************************************************************
564 ;; Fixme: This fails at least if the DTD contains conditional sections.
566 (defun xml-skip-dtd ()
567 "Skip the DTD at point.
568 This follows the rule [28] in the XML specifications."
569 (let ((xml-validating-parser nil))
570 (xml-parse-dtd)))
572 (defun xml-parse-dtd (&optional parse-ns)
573 "Parse the DTD at point."
574 (forward-char (eval-when-compile (length "<!DOCTYPE")))
575 (skip-syntax-forward " ")
576 (if (and (looking-at ">")
577 xml-validating-parser)
578 (error "XML: (Validity) Invalid DTD (expecting name of the document)"))
580 ;; Get the name of the document
581 (looking-at xml-name-regexp)
582 (let ((dtd (list (match-string-no-properties 0) 'dtd))
583 type element end-pos)
584 (goto-char (match-end 0))
586 (skip-syntax-forward " ")
587 ;; XML [75]
588 (cond ((looking-at "PUBLIC\\s-+")
589 (goto-char (match-end 0))
590 (unless (or (re-search-forward
591 "\\=\"\\([[:space:][:alnum:]-'()+,./:=?;!*#@$_%]*\\)\""
592 nil t)
593 (re-search-forward
594 "\\='\\([[:space:][:alnum:]-()+,./:=?;!*#@$_%]*\\)'"
595 nil t))
596 (error "XML: Missing Public ID"))
597 (let ((pubid (match-string-no-properties 1)))
598 (skip-syntax-forward " ")
599 (unless (or (re-search-forward "\\='\\([^']*\\)'" nil t)
600 (re-search-forward "\\=\"\\([^\"]*\\)\"" nil t))
601 (error "XML: Missing System ID"))
602 (push (list pubid (match-string-no-properties 1) 'public) dtd)))
603 ((looking-at "SYSTEM\\s-+")
604 (goto-char (match-end 0))
605 (unless (or (re-search-forward "\\='\\([^']*\\)'" nil t)
606 (re-search-forward "\\=\"\\([^\"]*\\)\"" nil t))
607 (error "XML: Missing System ID"))
608 (push (list (match-string-no-properties 1) 'system) dtd)))
609 (skip-syntax-forward " ")
610 (if (eq ?> (char-after))
611 (forward-char)
612 (if (not (eq (char-after) ?\[))
613 (error "XML: Bad DTD")
614 (forward-char)
615 ;; Parse the rest of the DTD
616 ;; Fixme: Deal with NOTATION, PIs.
617 (while (not (looking-at "\\s-*\\]"))
618 (skip-syntax-forward " ")
619 (cond
621 ;; Translation of rule [45] of XML specifications
622 ((looking-at
623 "<!ELEMENT\\s-+\\([[:alnum:].%;]+\\)\\s-+\\([^>]+\\)>")
625 (setq element (match-string-no-properties 1)
626 type (match-string-no-properties 2))
627 (setq end-pos (match-end 0))
629 ;; Translation of rule [46] of XML specifications
630 (cond
631 ((string-match "^EMPTY[ \t\n\r]*$" type) ;; empty declaration
632 (setq type 'empty))
633 ((string-match "^ANY[ \t\n\r]*$" type) ;; any type of contents
634 (setq type 'any))
635 ((string-match "^(\\(.*\\))[ \t\n\r]*$" type) ;; children ([47])
636 (setq type (xml-parse-elem-type (match-string-no-properties 1 type))))
637 ((string-match "^%[^;]+;[ \t\n\r]*$" type) ;; substitution
638 nil)
640 (if xml-validating-parser
641 (error "XML: (Validity) Invalid element type in the DTD"))))
643 ;; rule [45]: the element declaration must be unique
644 (if (and (assoc element dtd)
645 xml-validating-parser)
646 (error "XML: (Validity) Element declarations must be unique in a DTD (<%s>)"
647 element))
649 ;; Store the element in the DTD
650 (push (list element type) dtd)
651 (goto-char end-pos))
653 ;; Translation of rule [52] of XML specifications
654 ((looking-at (concat "<!ATTLIST[ \t\n\r]*\\(" xml-name-re
655 "\\)[ \t\n\r]*\\(" xml-att-def-re
656 "\\)*[ \t\n\r]*>"))
658 ;; We don't do anything with ATTLIST currently
659 (goto-char (match-end 0)))
661 ((looking-at "<!--")
662 (search-forward "-->"))
663 ((looking-at (concat "<!ENTITY[ \t\n\r]*\\(" xml-name-re
664 "\\)[ \t\n\r]*\\(" xml-entity-value-re
665 "\\)[ \t\n\r]*>"))
666 (let ((name (match-string-no-properties 1))
667 (value (substring (match-string-no-properties 2) 1
668 (- (length (match-string-no-properties 2)) 1))))
669 (goto-char (match-end 0))
670 (setq xml-entity-alist
671 (append xml-entity-alist
672 (list (cons name
673 (with-temp-buffer
674 (insert value)
675 (goto-char (point-min))
676 (xml-parse-fragment
677 xml-validating-parser
678 parse-ns))))))))
679 ((or (looking-at (concat "<!ENTITY[ \t\n\r]+\\(" xml-name-re
680 "\\)[ \t\n\r]+SYSTEM[ \t\n\r]+"
681 "\\(\"[^\"]*\"\\|'[^']*'\\)[ \t\n\r]*>"))
682 (looking-at (concat "<!ENTITY[ \t\n\r]+\\(" xml-name-re
683 "\\)[ \t\n\r]+PUBLIC[ \t\n\r]+"
684 "\"[- \r\na-zA-Z0-9'()+,./:=?;!*#@$_%]*\""
685 "\\|'[- \r\na-zA-Z0-9()+,./:=?;!*#@$_%]*'"
686 "[ \t\n\r]+\\(\"[^\"]*\"\\|'[^']*'\\)"
687 "[ \t\n\r]*>")))
688 (let ((name (match-string-no-properties 1))
689 (file (substring (match-string-no-properties 2) 1
690 (- (length (match-string-no-properties 2)) 1))))
691 (goto-char (match-end 0))
692 (setq xml-entity-alist
693 (append xml-entity-alist
694 (list (cons name (with-temp-buffer
695 (insert-file-contents file)
696 (goto-char (point-min))
697 (xml-parse-fragment
698 xml-validating-parser
699 parse-ns))))))))
700 ;; skip parameter entity declarations
701 ((or (looking-at (concat "<!ENTITY[ \t\n\r]+%[ \t\n\r]+\\(" xml-name-re
702 "\\)[ \t\n\r]+SYSTEM[ \t\n\r]+"
703 "\\(\"[^\"]*\"\\|'[^']*'\\)[ \t\n\r]*>"))
704 (looking-at (concat "<!ENTITY[ \t\n\r]+"
705 "%[ \t\n\r]+"
706 "\\(" xml-name-re "\\)[ \t\n\r]+"
707 "PUBLIC[ \t\n\r]+"
708 "\\(\"[- \r\na-zA-Z0-9'()+,./:=?;!*#@$_%]*\""
709 "\\|'[- \r\na-zA-Z0-9()+,./:=?;!*#@$_%]*'\\)[ \t\n\r]+"
710 "\\(\"[^\"]+\"\\|'[^']+'\\)"
711 "[ \t\n\r]*>")))
712 (goto-char (match-end 0)))
713 ;; skip parameter entities
714 ((looking-at (concat "%" xml-name-re ";"))
715 (goto-char (match-end 0)))
717 (when xml-validating-parser
718 (error "XML: (Validity) Invalid DTD item"))))))
719 (if (looking-at "\\s-*]>")
720 (goto-char (match-end 0))))
721 (nreverse dtd)))
723 (defun xml-parse-elem-type (string)
724 "Convert element type STRING into a Lisp structure."
726 (let (elem modifier)
727 (if (string-match "(\\([^)]+\\))\\([+*?]?\\)" string)
728 (progn
729 (setq elem (match-string-no-properties 1 string)
730 modifier (match-string-no-properties 2 string))
731 (if (string-match "|" elem)
732 (setq elem (cons 'choice
733 (mapcar 'xml-parse-elem-type
734 (split-string elem "|"))))
735 (if (string-match "," elem)
736 (setq elem (cons 'seq
737 (mapcar 'xml-parse-elem-type
738 (split-string elem ",")))))))
739 (if (string-match "[ \t\n\r]*\\([^+*?]+\\)\\([+*?]?\\)" string)
740 (setq elem (match-string-no-properties 1 string)
741 modifier (match-string-no-properties 2 string))))
743 (if (and (stringp elem) (string= elem "#PCDATA"))
744 (setq elem 'pcdata))
746 (cond
747 ((string= modifier "+")
748 (list '+ elem))
749 ((string= modifier "*")
750 (list '* elem))
751 ((string= modifier "?")
752 (list '\? elem))
754 elem))))
756 ;;*******************************************************************
757 ;;**
758 ;;** Substituting special XML sequences
759 ;;**
760 ;;*******************************************************************
762 (defun xml-substitute-special (string)
763 "Return STRING, after subsituting entity references."
764 ;; This originally made repeated passes through the string from the
765 ;; beginning, which isn't correct, since then either "&amp;amp;" or
766 ;; "&#38;amp;" won't DTRT.
768 (let ((point 0)
769 children end-point)
770 (while (string-match "&\\([^;]*\\);" string point)
771 (setq end-point (match-end 0))
772 (let* ((this-part (match-string-no-properties 1 string))
773 (prev-part (substring string point (match-beginning 0)))
774 (entity (assoc this-part xml-entity-alist))
775 (expansion
776 (cond ((string-match "#\\([0-9]+\\)" this-part)
777 (let ((c (decode-char
778 'ucs
779 (string-to-number (match-string-no-properties 1 this-part)))))
780 (if c (string c))))
781 ((string-match "#x\\([[:xdigit:]]+\\)" this-part)
782 (let ((c (decode-char
783 'ucs
784 (string-to-number (match-string-no-properties 1 this-part) 16))))
785 (if c (string c))))
786 (entity
787 (cdr entity))
788 ((eq (length this-part) 0)
789 (error "XML: (Not Well-Formed) No entity given"))
791 (if xml-validating-parser
792 (error "XML: (Validity) Undefined entity `%s'"
793 this-part)
794 xml-undefined-entity)))))
796 (cond ((null children)
797 ;; FIXME: If we have an entity that expands into XML, this won't work.
798 (setq children
799 (concat prev-part expansion)))
800 ((stringp children)
801 (if (stringp expansion)
802 (setq children (concat children prev-part expansion))
803 (setq children (list expansion (concat prev-part children)))))
804 ((and (stringp expansion)
805 (stringp (car children)))
806 (setcar children (concat prev-part expansion (car children))))
807 ((stringp expansion)
808 (setq children (append (concat prev-part expansion)
809 children)))
810 ((stringp (car children))
811 (setcar children (concat (car children) prev-part))
812 (setq children (append expansion children)))
814 (setq children (list expansion
815 prev-part
816 children))))
817 (setq point end-point)))
818 (cond ((stringp children)
819 (concat children (substring string point)))
820 ((stringp (car (last children)))
821 (concat (car (last children)) (substring string point)))
822 ((null children)
823 string)
825 (concat (mapconcat 'identity
826 (nreverse children)
828 (substring string point))))))
830 ;;*******************************************************************
831 ;;**
832 ;;** Printing a tree.
833 ;;** This function is intended mainly for debugging purposes.
834 ;;**
835 ;;*******************************************************************
837 (defun xml-debug-print (xml &optional indent-string)
838 "Outputs the XML in the current buffer.
839 XML can be a tree or a list of nodes.
840 The first line is indented with the optional INDENT-STRING."
841 (setq indent-string (or indent-string ""))
842 (dolist (node xml)
843 (xml-debug-print-internal node indent-string)))
845 (defalias 'xml-print 'xml-debug-print)
847 (defun xml-escape-string (string)
848 "Return the string with entity substitutions made from
849 xml-entity-alist."
850 (mapconcat (lambda (byte)
851 (let ((char (char-to-string byte)))
852 (if (rassoc char xml-entity-alist)
853 (concat "&" (car (rassoc char xml-entity-alist)) ";")
854 char)))
855 ;; This differs from the non-unicode branch. Just
856 ;; grabbing the string works here.
857 string ""))
859 (defun xml-debug-print-internal (xml indent-string)
860 "Outputs the XML tree in the current buffer.
861 The first line is indented with INDENT-STRING."
862 (let ((tree xml)
863 attlist)
864 (insert indent-string ?< (symbol-name (xml-node-name tree)))
866 ;; output the attribute list
867 (setq attlist (xml-node-attributes tree))
868 (while attlist
869 (insert ?\ (symbol-name (caar attlist)) "=\""
870 (xml-escape-string (cdar attlist)) ?\")
871 (setq attlist (cdr attlist)))
873 (setq tree (xml-node-children tree))
875 (if (null tree)
876 (insert ?/ ?>)
877 (insert ?>)
879 ;; output the children
880 (dolist (node tree)
881 (cond
882 ((listp node)
883 (insert ?\n)
884 (xml-debug-print-internal node (concat indent-string " ")))
885 ((stringp node)
886 (insert (xml-escape-string node)))
888 (error "Invalid XML tree"))))
890 (when (not (and (null (cdr tree))
891 (stringp (car tree))))
892 (insert ?\n indent-string))
893 (insert ?< ?/ (symbol-name (xml-node-name xml)) ?>))))
895 (provide 'xml)
897 ;; arch-tag: 5864b283-5a68-4b59-a20d-36a72b353b9b
898 ;;; xml.el ends here