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1 | ;;; ebnf-yac --- Parser for Yacc/Bison |
2 | ||
8d9ea7b1 | 3 | ;; Copyright (C) 1999, 2000 Free Sofware Foundation, Inc. |
984ae001 GM |
4 | |
5 | ;; Author: Vinicius Jose Latorre <vinicius@cpqd.com.br> | |
6 | ;; Maintainer: Vinicius Jose Latorre <vinicius@cpqd.com.br> | |
7 | ;; Keywords: wp, ebnf, PostScript | |
8 | ;; Time-stamp: <99/11/20 18:02:43 vinicius> | |
9 | ;; Version: 1.0 | |
10 | ||
8d9ea7b1 | 11 | ;; This file is part of GNU Emacs. |
984ae001 | 12 | |
8d9ea7b1 | 13 | ;; GNU Emacs is free software; you can redistribute it and/or modify |
984ae001 GM |
14 | ;; it under the terms of the GNU General Public License as published by |
15 | ;; the Free Software Foundation; either version 2, or (at your option) | |
16 | ;; any later version. | |
17 | ||
8d9ea7b1 | 18 | ;; GNU Emacs is distributed in the hope that it will be useful, |
984ae001 GM |
19 | ;; but WITHOUT ANY WARRANTY; without even the implied warranty of |
20 | ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
21 | ;; GNU General Public License for more details. | |
22 | ||
23 | ;; You should have received a copy of the GNU General Public License | |
24 | ;; along with GNU Emacs; see the file COPYING. If not, write to the | |
25 | ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330, | |
26 | ;; Boston, MA 02111-1307, USA. | |
27 | ||
28 | ;;; Commentary: | |
29 | ||
30 | ;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; | |
31 | ;; | |
32 | ;; | |
33 | ;; This is part of ebnf2ps package. | |
34 | ;; | |
35 | ;; This package defines a parser for Yacc/Bison. | |
36 | ;; | |
37 | ;; See ebnf2ps.el for documentation. | |
38 | ;; | |
39 | ;; | |
40 | ;; Yacc/Bison Syntax | |
41 | ;; ----------------- | |
42 | ;; | |
43 | ;; YACC = { YACC-Definitions }* "%%" { YACC-Rule }* [ "%%" [ YACC-Code ] ]. | |
44 | ;; | |
45 | ;; YACC-Definitions = "%token" [ "<" Name ">" ] Name-List | |
46 | ;; | "any other Yacc definition" | |
47 | ;; . | |
48 | ;; | |
49 | ;; YACC-Code = "any C definition". | |
50 | ;; | |
51 | ;; YACC-Rule = Name ":" Alternative ";". | |
52 | ;; | |
53 | ;; Alternative = { Sequence || "|" }*. | |
54 | ;; | |
55 | ;; Sequence = { Factor }*. | |
56 | ;; | |
57 | ;; Factor = Name | |
58 | ;; | "'" "character" "'" | |
59 | ;; | "error" | |
60 | ;; | "{" "C like commands" "}" | |
61 | ;; . | |
62 | ;; | |
63 | ;; Name-List = { Name || "," }*. | |
64 | ;; | |
65 | ;; Name = "[A-Za-z][A-Za-z0-9_.]*". | |
66 | ;; | |
67 | ;; Comment = "/*" "any character, but the sequence \"*/\"" "*/" | |
68 | ;; | "//" "any character" "\\n". | |
69 | ;; | |
70 | ;; | |
71 | ;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; | |
72 | ||
73 | ;;; code: | |
74 | ||
75 | ||
76 | (require 'ebnf-otz) | |
77 | ||
78 | ||
79 | (defvar ebnf-yac-lex nil | |
80 | "Value returned by `ebnf-yac-lex' function.") | |
81 | ||
82 | ||
83 | (defvar ebnf-yac-token-list nil | |
84 | "List of `%TOKEN' names.") | |
85 | ||
86 | ||
87 | (defvar ebnf-yac-skip-char nil | |
88 | "Non-nil means skip printable characters with no grammatical meaning.") | |
89 | ||
90 | ||
91 | (defvar ebnf-yac-error nil | |
92 | "Non-nil means \"error\" occured.") | |
93 | ||
94 | \f | |
95 | ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; | |
96 | ;; Syntatic analyzer | |
97 | ||
98 | ||
99 | ;;; YACC = { YACC-Definitions }* "%%" { YACC-Rule }* [ "%%" [ YACC-Code ] ]. | |
100 | ;;; | |
101 | ;;; YACC-Code = "any C definition". | |
102 | ||
103 | (defun ebnf-yac-parser (start) | |
104 | "yacc/Bison parser." | |
105 | (let ((total (+ (- ebnf-limit start) 1)) | |
106 | (bias (1- start)) | |
107 | (origin (point)) | |
108 | syntax-list token rule) | |
109 | (goto-char start) | |
110 | (setq token (ebnf-yac-lex)) | |
111 | (and (eq token 'end-of-input) | |
112 | (error "Invalid Yacc/Bison file format.")) | |
113 | (or (eq (ebnf-yac-definitions token) 'yac-separator) | |
114 | (error "Missing `%%%%'.")) | |
115 | (setq token (ebnf-yac-lex)) | |
116 | (while (not (memq token '(end-of-input yac-separator))) | |
117 | (ebnf-message-float | |
118 | "Parsing...%s%%" | |
119 | (/ (* (- (point) bias) 100.0) total)) | |
120 | (setq token (ebnf-yac-rule token) | |
121 | rule (cdr token) | |
122 | token (car token)) | |
123 | (or (ebnf-add-empty-rule-list rule) | |
124 | (setq syntax-list (cons rule syntax-list)))) | |
125 | (goto-char origin) | |
126 | syntax-list)) | |
127 | ||
128 | ||
129 | ;;; YACC-Definitions = "%token" [ "<" Name ">" ] Name-List | |
130 | ;;; | "any other Yacc definition" | |
131 | ;;; . | |
132 | ||
133 | (defun ebnf-yac-definitions (token) | |
134 | (let ((ebnf-yac-skip-char t)) | |
135 | (while (not (memq token '(yac-separator end-of-input))) | |
136 | (setq token | |
137 | (cond | |
138 | ;; "%token" [ "<" Name ">" ] Name-List | |
139 | ((eq token 'yac-token) | |
140 | (setq token (ebnf-yac-lex)) | |
141 | (when (eq token 'open-angle) | |
142 | (or (eq (ebnf-yac-lex) 'non-terminal) | |
143 | (error "Missing type name.")) | |
144 | (or (eq (ebnf-yac-lex) 'close-angle) | |
145 | (error "Missing `>'.")) | |
146 | (setq token (ebnf-yac-lex))) | |
147 | (setq token (ebnf-yac-name-list token) | |
148 | ebnf-yac-token-list (nconc (cdr token) | |
149 | ebnf-yac-token-list)) | |
150 | (car token)) | |
151 | ;; "any other Yacc definition" | |
152 | (t | |
153 | (ebnf-yac-lex)) | |
154 | ))) | |
155 | token)) | |
156 | ||
157 | ||
158 | ;;; YACC-Rule = Name ":" Alternative ";". | |
159 | ||
160 | (defun ebnf-yac-rule (token) | |
161 | (let ((header ebnf-yac-lex) | |
162 | (action ebnf-action) | |
163 | body) | |
164 | (setq ebnf-action nil) | |
165 | (or (eq token 'non-terminal) | |
166 | (error "Invalid rule name.")) | |
167 | (or (eq (ebnf-yac-lex) 'colon) | |
168 | (error "Invalid rule: missing `:'.")) | |
169 | (setq body (ebnf-yac-alternative)) | |
170 | (or (eq (car body) 'period) | |
171 | (error "Invalid rule: missing `;'.")) | |
172 | (setq body (cdr body)) | |
173 | (ebnf-eps-add-production header) | |
174 | (cons (ebnf-yac-lex) | |
175 | (ebnf-make-production header body action)))) | |
176 | ||
177 | ||
178 | ;;; Alternative = { Sequence || "|" }*. | |
179 | ||
180 | (defun ebnf-yac-alternative () | |
181 | (let (body sequence) | |
182 | (while (eq (car (setq sequence (ebnf-yac-sequence))) | |
183 | 'alternative) | |
184 | (and (setq sequence (cdr sequence)) | |
185 | (setq body (cons sequence body)))) | |
186 | (ebnf-token-alternative body sequence))) | |
187 | ||
188 | ||
189 | ;;; Sequence = { Factor }*. | |
190 | ||
191 | (defun ebnf-yac-sequence () | |
192 | (let (ebnf-yac-error token seq factor) | |
193 | (while (setq token (ebnf-yac-lex) | |
194 | factor (ebnf-yac-factor token)) | |
195 | (setq seq (cons factor seq))) | |
196 | (cons token | |
197 | (cond | |
198 | ;; ignore error recovery | |
199 | ((and ebnf-yac-ignore-error-recovery ebnf-yac-error) | |
200 | nil) | |
201 | ;; null sequence | |
202 | ((null seq) | |
203 | (ebnf-make-empty)) | |
204 | ;; sequence with only one element | |
205 | ((= (length seq) 1) | |
206 | (car seq)) | |
207 | ;; a real sequence | |
208 | (t | |
209 | (ebnf-make-sequence (nreverse seq))) | |
210 | )))) | |
211 | ||
212 | ||
213 | ;;; Factor = Name | |
214 | ;;; | "'" "character" "'" | |
215 | ;;; | "error" | |
216 | ;;; | "{" "C like commands" "}" | |
217 | ;;; . | |
218 | ||
219 | (defun ebnf-yac-factor (token) | |
220 | (cond | |
221 | ;; 'character' | |
222 | ((eq token 'terminal) | |
223 | (ebnf-make-terminal ebnf-yac-lex)) | |
224 | ;; Name | |
225 | ((eq token 'non-terminal) | |
226 | (ebnf-make-non-terminal ebnf-yac-lex)) | |
227 | ;; "error" | |
228 | ((eq token 'yac-error) | |
229 | (ebnf-make-special ebnf-yac-lex)) | |
230 | ;; not a factor | |
231 | (t | |
232 | nil) | |
233 | )) | |
234 | ||
235 | ||
236 | ;;; Name-List = { Name || "," }*. | |
237 | ||
238 | (defun ebnf-yac-name-list (token) | |
239 | (let (names) | |
240 | (when (eq token 'non-terminal) | |
241 | (while (progn | |
242 | (setq names (cons ebnf-yac-lex names) | |
243 | token (ebnf-yac-lex)) | |
244 | (eq token 'comma)) | |
245 | (or (eq (ebnf-yac-lex) 'non-terminal) | |
246 | (error "Missing token name.")))) | |
247 | (cons token names))) | |
248 | ||
249 | \f | |
250 | ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; | |
251 | ;; Lexical analyzer | |
252 | ||
253 | ||
254 | ;;; Name = "[A-Za-z][A-Za-z0-9_.]*". | |
255 | ;;; | |
256 | ;;; Comment = "/*" "any character, but the sequence \"*/\"" "*/" | |
257 | ;;; | "//" "any character" "\\n". | |
258 | ||
259 | (defconst ebnf-yac-token-table | |
260 | ;; control character & 8-bit character are set to `error' | |
261 | (let ((table (make-vector 256 'error))) | |
262 | ;; upper & lower case letters: | |
263 | (mapcar | |
264 | #'(lambda (char) | |
265 | (aset table char 'non-terminal)) | |
266 | "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz") | |
267 | ;; printable characters: | |
268 | (mapcar | |
269 | #'(lambda (char) | |
270 | (aset table char 'character)) | |
271 | "!#$&()*+-.0123456789=?@[\\]^_`~") | |
272 | ;; Override space characters: | |
273 | (aset table ?\n 'space) ; [NL] linefeed | |
274 | (aset table ?\r 'space) ; [CR] carriage return | |
275 | (aset table ?\t 'space) ; [HT] horizontal tab | |
276 | (aset table ?\ 'space) ; [SP] space | |
277 | ;; Override form feed character: | |
278 | (aset table ?\f 'form-feed) ; [FF] form feed | |
279 | ;; Override other lexical characters: | |
280 | (aset table ?< 'open-angle) | |
281 | (aset table ?> 'close-angle) | |
282 | (aset table ?, 'comma) | |
283 | (aset table ?% 'yac-pragma) | |
284 | (aset table ?/ 'slash) | |
285 | (aset table ?\{ 'yac-code) | |
286 | (aset table ?\" 'string) | |
287 | (aset table ?\' 'terminal) | |
288 | (aset table ?: 'colon) | |
289 | (aset table ?| 'alternative) | |
290 | (aset table ?\; 'period) | |
291 | table) | |
292 | "Vector used to map characters to a lexical token.") | |
293 | ||
294 | ||
295 | (defun ebnf-yac-initialize () | |
296 | "Initializations for Yacc/Bison parser." | |
297 | (setq ebnf-yac-token-list nil)) | |
298 | ||
299 | ||
300 | (defun ebnf-yac-lex () | |
301 | "Lexical analyser for Yacc/Bison. | |
302 | ||
303 | Return a lexical token. | |
304 | ||
305 | See documentation for variable `ebnf-yac-lex'." | |
306 | (if (>= (point) ebnf-limit) | |
307 | 'end-of-input | |
308 | (let (token) | |
309 | ;; skip spaces, code blocks and comments | |
310 | (while (if (> (following-char) 255) | |
311 | (progn | |
312 | (setq token 'error) | |
313 | nil) | |
314 | (setq token (aref ebnf-yac-token-table (following-char))) | |
315 | (cond | |
316 | ((or (eq token 'space) | |
317 | (and ebnf-yac-skip-char | |
318 | (eq token 'character))) | |
319 | (ebnf-yac-skip-spaces)) | |
320 | ((eq token 'yac-code) | |
321 | (ebnf-yac-skip-code)) | |
322 | ((eq token 'slash) | |
323 | (ebnf-yac-handle-comment)) | |
324 | ((eq token 'form-feed) | |
325 | (forward-char) | |
326 | (setq ebnf-action 'form-feed)) | |
327 | (t nil) | |
328 | ))) | |
329 | (cond | |
330 | ;; end of input | |
331 | ((>= (point) ebnf-limit) | |
332 | 'end-of-input) | |
333 | ;; error | |
334 | ((eq token 'error) | |
335 | (error "Illegal character.")) | |
336 | ;; "string" | |
337 | ((eq token 'string) | |
338 | (setq ebnf-yac-lex (ebnf-get-string)) | |
339 | 'string) | |
340 | ;; terminal: 'char' | |
341 | ((eq token 'terminal) | |
342 | (setq ebnf-yac-lex (ebnf-string " -&(-~" ?\' "terminal")) | |
343 | 'terminal) | |
344 | ;; non-terminal, terminal or "error" | |
345 | ((eq token 'non-terminal) | |
346 | (setq ebnf-yac-lex (ebnf-buffer-substring "0-9A-Za-z_.")) | |
347 | (cond ((member ebnf-yac-lex ebnf-yac-token-list) | |
348 | 'terminal) | |
349 | ((string= ebnf-yac-lex "error") | |
350 | (setq ebnf-yac-error t) | |
351 | 'yac-error) | |
352 | (t | |
353 | 'non-terminal) | |
354 | )) | |
355 | ;; %% and Yacc pragmas (%TOKEN, %START, etc). | |
356 | ((eq token 'yac-pragma) | |
357 | (forward-char) | |
358 | (cond | |
359 | ;; Yacc separator | |
360 | ((eq (following-char) ?%) | |
361 | (forward-char) | |
362 | 'yac-separator) | |
363 | ;; %TOKEN | |
364 | ((string= (upcase (ebnf-buffer-substring "0-9A-Za-z_")) "TOKEN") | |
365 | 'yac-token) | |
366 | ;; other Yacc pragmas | |
367 | (t | |
368 | 'yac-pragma) | |
369 | )) | |
370 | ;; miscellaneous | |
371 | (t | |
372 | (forward-char) | |
373 | token) | |
374 | )))) | |
375 | ||
376 | ||
377 | (defun ebnf-yac-skip-spaces () | |
378 | (skip-chars-forward | |
379 | (if ebnf-yac-skip-char | |
380 | "\n\r\t !#$&()*+-.0123456789=?@[\\\\]^_`~" | |
381 | "\n\r\t ") | |
382 | ebnf-limit) | |
383 | (< (point) ebnf-limit)) | |
384 | ||
385 | ||
386 | (defun ebnf-yac-skip-code () | |
387 | (forward-char) | |
388 | (let ((pair 1)) | |
389 | (while (> pair 0) | |
390 | (skip-chars-forward "^{}/'\"\000-\010\013\016-\037\177-\377" ebnf-limit) | |
391 | (cond | |
392 | ((= (following-char) ?{) | |
393 | (forward-char) | |
394 | (setq pair (1+ pair))) | |
395 | ((= (following-char) ?}) | |
396 | (forward-char) | |
397 | (setq pair (1- pair))) | |
398 | ((= (following-char) ?/) | |
399 | (ebnf-yac-handle-comment)) | |
400 | ((= (following-char) ?\") | |
401 | (ebnf-get-string)) | |
402 | ((= (following-char) ?\') | |
403 | (ebnf-string " -&(-~" ?\' "character")) | |
404 | (t | |
405 | (error "Illegal character.")) | |
406 | ))) | |
407 | (ebnf-yac-skip-spaces)) | |
408 | ||
409 | ||
410 | (defun ebnf-yac-handle-comment () | |
411 | (forward-char) | |
412 | (cond | |
413 | ;; begin comment | |
414 | ((= (following-char) ?*) | |
415 | (ebnf-yac-skip-comment) | |
416 | (ebnf-yac-skip-spaces)) | |
417 | ;; line comment | |
418 | ((= (following-char) ?/) | |
419 | (end-of-line) | |
420 | (ebnf-yac-skip-spaces)) | |
421 | ;; no comment | |
422 | (t nil) | |
423 | )) | |
424 | ||
425 | ||
426 | (defconst ebnf-yac-comment-chars "^*\000-\010\013\016-\037\177-\237") | |
427 | ||
428 | ||
429 | (defun ebnf-yac-skip-comment () | |
430 | (forward-char) | |
431 | (cond | |
432 | ;; open EPS file | |
433 | ((and ebnf-eps-executing (= (following-char) ?\[)) | |
434 | (ebnf-eps-add-context (ebnf-yac-eps-filename))) | |
435 | ;; close EPS file | |
436 | ((and ebnf-eps-executing (= (following-char) ?\])) | |
437 | (ebnf-eps-remove-context (ebnf-yac-eps-filename))) | |
438 | ;; any other action in comment | |
439 | (t | |
440 | (setq ebnf-action (aref ebnf-comment-table (following-char)))) | |
441 | ) | |
442 | (let ((not-end t)) | |
443 | (while not-end | |
444 | (skip-chars-forward ebnf-yac-comment-chars ebnf-limit) | |
445 | (cond ((>= (point) ebnf-limit) | |
446 | (error "Missing end of comment: `*/'.")) | |
447 | ((= (following-char) ?*) | |
448 | (skip-chars-forward "*" ebnf-limit) | |
449 | (when (= (following-char) ?/) | |
450 | ;; end of comment | |
451 | (forward-char) | |
452 | (setq not-end nil))) | |
453 | (t | |
454 | (error "Illegal character.")) | |
455 | )))) | |
456 | ||
457 | ||
458 | (defun ebnf-yac-eps-filename () | |
459 | (forward-char) | |
460 | (buffer-substring-no-properties | |
461 | (point) | |
462 | (let ((chars (concat ebnf-yac-comment-chars "\n")) | |
463 | found) | |
464 | (while (not found) | |
465 | (skip-chars-forward chars ebnf-limit) | |
466 | (setq found | |
467 | (cond ((>= (point) ebnf-limit) | |
468 | (point)) | |
469 | ((= (following-char) ?*) | |
470 | (skip-chars-forward "*" ebnf-limit) | |
471 | (if (/= (following-char) ?\/) | |
472 | nil | |
473 | (backward-char) | |
474 | (point))) | |
475 | (t | |
476 | (point)) | |
477 | ))) | |
478 | found))) | |
479 | ||
480 | \f | |
481 | ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; | |
482 | ||
483 | ||
484 | (provide 'ebnf-yac) | |
485 | ||
486 | ||
487 | ;;; ebnf-yac.el ends here |