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Prepare @$ in %destructor, but currently don't bind it in the
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1 /* Bison Grammar Scanner -*- C -*-
2 Copyright (C) 2002 Free Software Foundation, Inc.
3
4 This file is part of Bison, the GNU Compiler Compiler.
5
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
10
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
19 02111-1307 USA
20 */
21
22 %option debug nodefault noyywrap nounput never-interactive stack
23 %option prefix="gram_" outfile="lex.yy.c"
24
25 %{
26 #include "system.h"
27 #include "complain.h"
28 #include "quote.h"
29 #include "getargs.h"
30 #include "gram.h"
31 #include "reader.h"
32
33 /* Each time we match a string, move the end cursor to its end. */
34 #define YY_USER_INIT \
35 do { \
36 LOCATION_RESET (*yylloc); \
37 /* This is only to avoid GCC warnings. */ \
38 if (yycontrol) {;}; \
39 } while (0)
40
41 #define YY_USER_ACTION LOCATION_COLUMNS (*yylloc, yyleng)
42 #define YY_LINES LOCATION_LINES (*yylloc, yyleng); lineno += yyleng;
43 #define YY_STEP LOCATION_STEP (*yylloc)
44
45
46 /* STRING_OBSTACK -- Used to store all the characters that we need to
47 keep (to construct ID, STRINGS etc.). Use the following macros to
48 use it.
49
50 Use YY_OBS_GROW to append what has just been matched, and
51 YY_OBS_FINISH to end the string (it puts the ending 0).
52 YY_OBS_FINISH also stores this string in LAST_STRING, which can be
53 used, and which is used by YY_OBS_FREE to free the last string. */
54
55 static struct obstack string_obstack;
56 char *last_string;
57
58 #define YY_OBS_GROW \
59 obstack_grow (&string_obstack, yytext, yyleng)
60
61 #define YY_OBS_FINISH \
62 do { \
63 obstack_1grow (&string_obstack, '\0'); \
64 last_string = obstack_finish (&string_obstack); \
65 } while (0)
66
67 #define YY_OBS_FREE \
68 do { \
69 obstack_free (&string_obstack, last_string); \
70 } while (0)
71
72 void
73 scanner_last_string_free (void)
74 {
75 YY_OBS_FREE;
76 }
77
78
79 static int braces_level = 0;
80 static int percent_percent_count = 0;
81
82 static void handle_dollar PARAMS ((braced_code_t code_kind,
83 char *cp, location_t location));
84 static void handle_at PARAMS ((braced_code_t code_kind,
85 char *cp, location_t location));
86
87 %}
88 %x SC_COMMENT
89 %x SC_STRING SC_CHARACTER
90 %x SC_ESCAPED_STRING SC_ESCAPED_CHARACTER
91 %x SC_BRACED_CODE SC_PROLOGUE SC_EPILOGUE
92
93 id [.a-zA-Z][.a-zA-Z_0-9]*
94 int [0-9]+
95 eols (\n|\r|\n\r|\r\n)+
96 blanks [ \t\f]+
97
98 %%
99 %{
100 /* At each yylex invocation, mark the current position as the
101 start of the next token. */
102 #define TR_POS 0
103 #if TR_POS
104 fprintf (stderr, "FOO1: %p: ", yylloc);
105 LOCATION_PRINT (stderr, *yylloc);
106 fprintf (stderr, "\n");
107 #endif
108 YY_STEP;
109 #if TR_POS
110 fprintf (stderr, "BAR1: ");
111 LOCATION_PRINT (stderr, *yylloc);
112 fprintf (stderr, "\n");
113 #endif
114 %}
115
116
117 /*----------------------------.
118 | Scanning Bison directives. |
119 `----------------------------*/
120 <INITIAL>
121 {
122 "%binary" return PERCENT_NONASSOC;
123 "%debug" return PERCENT_DEBUG;
124 "%define" return PERCENT_DEFINE;
125 "%defines" return PERCENT_DEFINES;
126 "%destructor" return PERCENT_DESTRUCTOR;
127 "%error"[-_]"verbose" return PERCENT_ERROR_VERBOSE;
128 "%expect" return PERCENT_EXPECT;
129 "%file-prefix" return PERCENT_FILE_PREFIX;
130 "%fixed"[-_]"output"[-_]"files" return PERCENT_YACC;
131 "%left" return PERCENT_LEFT;
132 "%locations" return PERCENT_LOCATIONS;
133 "%name"[-_]"prefix" return PERCENT_NAME_PREFIX;
134 "%no"[-_]"lines" return PERCENT_NO_LINES;
135 "%nonassoc" return PERCENT_NONASSOC;
136 "%nterm" return PERCENT_NTERM;
137 "%output" return PERCENT_OUTPUT;
138 "%prec" return PERCENT_PREC;
139 "%pure"[-_]"parser" return PERCENT_PURE_PARSER;
140 "%right" return PERCENT_RIGHT;
141 "%skeleton" return PERCENT_SKELETON;
142 "%start" return PERCENT_START;
143 "%term" return PERCENT_TOKEN;
144 "%token" return PERCENT_TOKEN;
145 "%token"[-_]"table" return PERCENT_TOKEN_TABLE;
146 "%type" return PERCENT_TYPE;
147 "%union" return PERCENT_UNION;
148 "%verbose" return PERCENT_VERBOSE;
149 "%yacc" return PERCENT_YACC;
150
151 "=" return EQUAL;
152 ":" return COLON;
153 "|" return PIPE;
154 ";" return SEMICOLON;
155
156 {eols} YY_LINES; YY_STEP;
157 {blanks} YY_STEP;
158 {id} {
159 yylval->symbol = getsym (yytext, *yylloc);
160 return ID;
161 }
162
163 {int} yylval->integer = strtol (yytext, 0, 10); return INT;
164
165 /* Characters. We don't check there is only one. */
166 \' YY_OBS_GROW; yy_push_state (SC_ESCAPED_CHARACTER);
167
168 /* Strings. */
169 \" YY_OBS_GROW; yy_push_state (SC_ESCAPED_STRING);
170
171 /* Comments. */
172 "/*" yy_push_state (SC_COMMENT);
173 "//".* YY_STEP;
174
175 /* Prologue. */
176 "%{" yy_push_state (SC_PROLOGUE);
177
178 /* Code in between braces. */
179 "{" YY_OBS_GROW; ++braces_level; yy_push_state (SC_BRACED_CODE);
180
181 /* A type. */
182 "<"[^>]+">" {
183 obstack_grow (&string_obstack, yytext + 1, yyleng - 2);
184 YY_OBS_FINISH;
185 yylval->string = last_string;
186 return TYPE;
187 }
188
189
190 "%%" {
191 if (++percent_percent_count == 2)
192 yy_push_state (SC_EPILOGUE);
193 return PERCENT_PERCENT;
194 }
195
196 . {
197 LOCATION_PRINT (stderr, *yylloc);
198 fprintf (stderr, ": invalid character: `%c'\n", *yytext);
199 YY_STEP;
200 }
201 }
202
203
204 /*------------------------------------------------------------.
205 | Whatever the start condition (but those which correspond to |
206 | entity `swallowed' by Bison: SC_ESCAPED_STRING and |
207 | SC_ESCAPED_CHARACTER), no M4 character must escape as is. |
208 `------------------------------------------------------------*/
209
210 <SC_COMMENT,SC_STRING,SC_CHARACTER,SC_BRACED_CODE,SC_PROLOGUE,SC_EPILOGUE>
211 {
212 \[ if (YY_START != SC_COMMENT) obstack_sgrow (&string_obstack, "@<:@");
213 \] if (YY_START != SC_COMMENT) obstack_sgrow (&string_obstack, "@:>@");
214 }
215
216
217
218 /*-----------------------------------------------------------.
219 | Scanning a C comment. The initial `/ *' is already eaten. |
220 `-----------------------------------------------------------*/
221
222 <SC_COMMENT>
223 {
224 "*/" { /* End of the comment. */
225 if (yy_top_state () == INITIAL)
226 {
227 YY_STEP;
228 }
229 else
230 {
231 YY_OBS_GROW;
232 }
233 yy_pop_state ();
234 }
235
236 [^\[\]*\n\r]+ if (yy_top_state () != INITIAL) YY_OBS_GROW;
237 {eols} if (yy_top_state () != INITIAL) YY_OBS_GROW; YY_LINES;
238 . /* Stray `*'. */if (yy_top_state () != INITIAL) YY_OBS_GROW;
239
240 <<EOF>> {
241 LOCATION_PRINT (stderr, *yylloc);
242 fprintf (stderr, ": unexpected end of file in a comment\n");
243 yy_pop_state ();
244 }
245 }
246
247
248 /*----------------------------------------------------------------.
249 | Scanning a C string, including its escapes. The initial `"' is |
250 | already eaten. |
251 `----------------------------------------------------------------*/
252
253 <SC_ESCAPED_STRING>
254 {
255 \" {
256 assert (yy_top_state () == INITIAL);
257 YY_OBS_GROW;
258 YY_OBS_FINISH;
259 yylval->string = last_string;
260 yy_pop_state ();
261 return STRING;
262 }
263
264 [^\"\n\r\\]+ YY_OBS_GROW;
265
266 {eols} obstack_1grow (&string_obstack, '\n'); YY_LINES;
267
268 <<EOF>> {
269 LOCATION_PRINT (stderr, *yylloc);
270 fprintf (stderr, ": unexpected end of file in a string\n");
271 assert (yy_top_state () == INITIAL);
272 YY_OBS_FINISH;
273 yylval->string = last_string;
274 yy_pop_state ();
275 return STRING;
276 }
277 }
278
279 /*---------------------------------------------------------------.
280 | Scanning a C character, decoding its escapes. The initial "'" |
281 | is already eaten. |
282 `---------------------------------------------------------------*/
283
284 <SC_ESCAPED_CHARACTER>
285 {
286 \' {
287 YY_OBS_GROW;
288 assert (yy_top_state () == INITIAL);
289 {
290 YY_OBS_FINISH;
291 yylval->symbol = getsym (last_string, *yylloc);
292 symbol_class_set (yylval->symbol, token_sym);
293 symbol_user_token_number_set (yylval->symbol, last_string[1]);
294 YY_OBS_FREE;
295 yy_pop_state ();
296 return ID;
297 }
298 }
299
300 [^\'\n\r\\] YY_OBS_GROW;
301
302 {eols} obstack_1grow (&string_obstack, '\n'); YY_LINES;
303
304 <<EOF>> {
305 LOCATION_PRINT (stderr, *yylloc);
306 fprintf (stderr, ": unexpected end of file in a character\n");
307 assert (yy_top_state () == INITIAL);
308 YY_OBS_FINISH;
309 yylval->string = last_string;
310 yy_pop_state ();
311 return CHARACTER;
312 }
313 }
314
315
316 /*----------------------------.
317 | Decode escaped characters. |
318 `----------------------------*/
319
320 <SC_ESCAPED_STRING,SC_ESCAPED_CHARACTER>
321 {
322 \\[0-7]{3} {
323 long c = strtol (yytext + 1, 0, 8);
324 if (c > 255)
325 {
326 LOCATION_PRINT (stderr, *yylloc);
327 fprintf (stderr, ": invalid escape: %s\n", yytext);
328 YY_STEP;
329 }
330 else
331 obstack_1grow (&string_obstack, c);
332 }
333
334 \\x[0-9a-fA-F]{2} {
335 obstack_1grow (&string_obstack, strtol (yytext + 2, 0, 16));
336 }
337
338 \\a obstack_1grow (&string_obstack, '\a');
339 \\b obstack_1grow (&string_obstack, '\b');
340 \\f obstack_1grow (&string_obstack, '\f');
341 \\n obstack_1grow (&string_obstack, '\n');
342 \\r obstack_1grow (&string_obstack, '\r');
343 \\t obstack_1grow (&string_obstack, '\t');
344 \\v obstack_1grow (&string_obstack, '\v');
345 \\[\\""] obstack_1grow (&string_obstack, yytext[1]);
346 \\. {
347 LOCATION_PRINT (stderr, *yylloc);
348 fprintf (stderr, ": unrecognized escape: %s\n", yytext);
349 YY_OBS_GROW;
350 }
351 }
352
353
354 /*----------------------------------------------------------.
355 | Scanning a C character without decoding its escapes. The |
356 | initial "'" is already eaten. |
357 `----------------------------------------------------------*/
358
359 <SC_CHARACTER>
360 {
361 \' {
362 YY_OBS_GROW;
363 assert (yy_top_state () != INITIAL);
364 yy_pop_state ();
365 }
366
367 [^\[\]\'\n\r\\] YY_OBS_GROW;
368 \\. YY_OBS_GROW;
369
370 {eols} YY_OBS_GROW; YY_LINES;
371
372 <<EOF>> {
373 LOCATION_PRINT (stderr, *yylloc);
374 fprintf (stderr, ": unexpected end of file in a character\n");
375 assert (yy_top_state () != INITIAL);
376 yy_pop_state ();
377 }
378 }
379
380
381 /*----------------------------------------------------------------.
382 | Scanning a C string, without decoding its escapes. The initial |
383 | `"' is already eaten. |
384 `----------------------------------------------------------------*/
385
386 <SC_STRING>
387 {
388 \" {
389 assert (yy_top_state () != INITIAL);
390 YY_OBS_GROW;
391 yy_pop_state ();
392 }
393
394 [^\[\]\"\n\r\\]+ YY_OBS_GROW;
395 \\. YY_OBS_GROW;
396
397 {eols} YY_OBS_GROW; YY_LINES;
398
399 <<EOF>> {
400 LOCATION_PRINT (stderr, *yylloc);
401 fprintf (stderr, ": unexpected end of file in a string\n");
402 assert (yy_top_state () != INITIAL);
403 yy_pop_state ();
404 }
405 }
406
407
408 /*---------------------------------------------------.
409 | Strings, comments etc. can be found in user code. |
410 `---------------------------------------------------*/
411
412 <SC_BRACED_CODE,SC_PROLOGUE,SC_EPILOGUE>
413 {
414 /* Characters. We don't check there is only one. */
415 \' YY_OBS_GROW; yy_push_state (SC_CHARACTER);
416
417 /* Strings. */
418 \" YY_OBS_GROW; yy_push_state (SC_STRING);
419
420 /* Comments. */
421 "/*" YY_OBS_GROW; yy_push_state (SC_COMMENT);
422 "//".* YY_OBS_GROW;
423 }
424
425
426 /*---------------------------------------------------------------.
427 | Scanning some code in braces (%union and actions). The initial |
428 | "{" is already eaten. |
429 `---------------------------------------------------------------*/
430
431 <SC_BRACED_CODE>
432 {
433 "}" {
434 YY_OBS_GROW;
435 if (--braces_level == 0)
436 {
437 yy_pop_state ();
438 YY_OBS_FINISH;
439 yylval->string = last_string;
440 return BRACED_CODE;
441 }
442 }
443
444 "{" YY_OBS_GROW; braces_level++;
445
446 "$"("<"[^>]+">")?(-?[0-9]+|"$") { handle_dollar (current_braced_code,
447 yytext, *yylloc); }
448 "@"(-?[0-9]+|"$") { handle_at (current_braced_code,
449 yytext, *yylloc); }
450
451 [^$@\[\]/\'\"\{\}\n\r]+ YY_OBS_GROW;
452 {eols} YY_OBS_GROW; YY_LINES;
453
454 /* A lose $, or /, or etc. */
455 . YY_OBS_GROW;
456
457 <<EOF>> {
458 LOCATION_PRINT (stderr, *yylloc);
459 fprintf (stderr, ": unexpected end of file in a braced code\n");
460 yy_pop_state ();
461 YY_OBS_FINISH;
462 yylval->string = last_string;
463 return BRACED_CODE;
464 }
465
466 }
467
468
469 /*--------------------------------------------------------------.
470 | Scanning some prologue: from "%{" (already scanned) to "%}". |
471 `--------------------------------------------------------------*/
472
473 <SC_PROLOGUE>
474 {
475 "%}" {
476 yy_pop_state ();
477 YY_OBS_FINISH;
478 yylval->string = last_string;
479 return PROLOGUE;
480 }
481
482 [^%\[\]/\'\"\n\r]+ YY_OBS_GROW;
483 "%"+[^%\}\n\r]+ YY_OBS_GROW;
484 {eols} YY_OBS_GROW; YY_LINES;
485
486 <<EOF>> {
487 LOCATION_PRINT (stderr, *yylloc);
488 fprintf (stderr, ": unexpected end of file in a prologue\n");
489 yy_pop_state ();
490 YY_OBS_FINISH;
491 yylval->string = last_string;
492 return PROLOGUE;
493 }
494
495 }
496
497
498 /*---------------------------------------------------------------.
499 | Scanning the epilogue (everything after the second "%%", which |
500 | has already been eaten. |
501 `---------------------------------------------------------------*/
502
503 <SC_EPILOGUE>
504 {
505 ([^\[\]]|{eols})+ YY_OBS_GROW;
506
507 <<EOF>> {
508 yy_pop_state ();
509 YY_OBS_FINISH;
510 yylval->string = last_string;
511 return EPILOGUE;
512 }
513 }
514
515
516 %%
517
518 /*------------------------------------------------------------------.
519 | CP is pointing to a wannabee semantic value (i.e., a `$'). |
520 | |
521 | Possible inputs: $[<TYPENAME>]($|integer) |
522 | |
523 | Output to the STRING_OBSTACK a reference to this semantic value. |
524 `------------------------------------------------------------------*/
525
526 static inline void
527 handle_action_dollar (char *cp, location_t location)
528 {
529 const char *type_name = NULL;
530
531 ++cp;
532
533 /* Get the type name if explicit. */
534 if (*cp == '<')
535 {
536 type_name = ++cp;
537 while (*cp != '>')
538 ++cp;
539 *cp = '\0';
540 ++cp;
541 }
542
543 if (*cp == '$')
544 {
545 if (!type_name)
546 type_name = symbol_list_n_type_name_get (current_rule, location, 0);
547 if (!type_name && typed)
548 complain_at (location, _("$$ of `%s' has no declared type"),
549 current_rule->sym->tag);
550 if (!type_name)
551 type_name = "";
552 obstack_fgrow1 (&string_obstack,
553 "]b4_lhs_value([%s])[", type_name);
554 }
555 else if (isdigit (*cp) || *cp == '-')
556 {
557 /* RULE_LENGTH is the number of values in the current rule so
558 far, which says where to find `$0' with respect to the top of
559 the stack. It is not the same as the rule->length in the
560 case of mid rule actions. */
561 int rule_length = symbol_list_length (current_rule->next);
562 int n = strtol (cp, &cp, 10);
563
564 if (n > rule_length)
565 complain_at (location, _("invalid value: %s%d"), "$", n);
566 else
567 {
568 if (!type_name && n > 0)
569 type_name = symbol_list_n_type_name_get (current_rule, location,
570 n);
571 if (!type_name && typed)
572 complain_at (location, _("$%d of `%s' has no declared type"),
573 n, current_rule->sym->tag);
574 if (!type_name)
575 type_name = "";
576 obstack_fgrow3 (&string_obstack,
577 "]b4_rhs_value([%d], [%d], [%s])[",
578 rule_length, n, type_name);
579 }
580 }
581 else
582 {
583 char buf[] = "$c";
584 buf[1] = *cp;
585 complain_at (location, _("%s is invalid"), quote (buf));
586 }
587 }
588
589
590 /*---------------------------------------.
591 | CP is pointing to $$ in a destructor. |
592 `---------------------------------------*/
593
594 static inline void
595 handle_destructor_dollar (char *cp, location_t location)
596 {
597 ++cp;
598 if (*cp == '$')
599 {
600 obstack_sgrow (&string_obstack, "]b4_dollar_dollar[");
601 }
602 else
603 {
604 char buf[] = "$c";
605 buf[1] = *cp;
606 complain_at (location, _("%s is invalid"), quote (buf));
607 }
608 }
609
610
611 /*-----------------------------------------------------------------.
612 | Dispatch onto handle_action_dollar, or handle_destructor_dollar, |
613 | depending upon CODE_KIND. |
614 `-----------------------------------------------------------------*/
615
616 static void
617 handle_dollar (braced_code_t braced_code_kind,
618 char *text, location_t location)
619 {
620 switch (braced_code_kind)
621 {
622 case action_braced_code:
623 handle_action_dollar (text, location);
624 break;
625
626 case destructor_braced_code:
627 handle_destructor_dollar (text, location);
628 break;
629 }
630 }
631
632
633 /*------------------------------------------------------.
634 | TEXT is a location token (i.e., a `@...'). Output to |
635 | STRING_OBSTACK a reference to this location. |
636 `------------------------------------------------------*/
637
638 static inline void
639 handle_action_at (char *text, location_t location)
640 {
641 locations_flag = 1;
642 ++text;
643
644 if (*text == '$')
645 {
646 obstack_sgrow (&string_obstack, "]b4_lhs_location[");
647 }
648 else if (isdigit (*text) || *text == '-')
649 {
650 /* RULE_LENGTH is the number of values in the current rule so
651 far, which says where to find `$0' with respect to the top of
652 the stack. It is not the same as the rule->length in the
653 case of mid rule actions. */
654 int rule_length = symbol_list_length (current_rule->next);
655 int n = strtol (text, &text, 10);
656
657 if (n > rule_length)
658 complain_at (location, _("invalid value: %s%d"), "@", n);
659 else
660 obstack_fgrow2 (&string_obstack, "]b4_rhs_location([%d], [%d])[",
661 rule_length, n);
662 }
663 else
664 {
665 char buf[] = "@c";
666 buf[1] = *text;
667 complain_at (location, _("%s is invalid"), quote (buf));
668 }
669 }
670
671
672 /*--------------------------------------------.
673 | TEXT is expexted tp be @$ in a destructor. |
674 `--------------------------------------------*/
675
676 static inline void
677 handle_destructor_at (char *text, location_t location)
678 {
679 ++text;
680 if (*text == '$')
681 {
682 obstack_sgrow (&string_obstack, "]b4_at_dollar[");
683 }
684 else
685 {
686 char buf[] = "$c";
687 buf[1] = *text;
688 complain_at (location, _("%s is invalid"), quote (buf));
689 }
690 }
691
692
693 /*-------------------------------------------------------------------.
694 | Dispatch onto handle_action_at, or handle_destructor_at, depending |
695 | upon CODE_KIND. |
696 `-------------------------------------------------------------------*/
697
698 static void
699 handle_at (braced_code_t braced_code_kind,
700 char *text, location_t location)
701 {
702 switch (braced_code_kind)
703 {
704 case action_braced_code:
705 handle_action_at (text, location);
706 break;
707
708 case destructor_braced_code:
709 handle_destructor_at (text, location);
710 break;
711 }
712 }
713
714
715 /*-------------------------.
716 | Initialize the scanner. |
717 `-------------------------*/
718
719 void
720 scanner_initialize (void)
721 {
722 obstack_init (&string_obstack);
723 }
724
725
726 /*-----------------------------------------------.
727 | Free all the memory allocated to the scanner. |
728 `-----------------------------------------------*/
729
730 void
731 scanner_free (void)
732 {
733 obstack_free (&string_obstack, 0);
734 }