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e9955c83 1/* Bison Grammar Scanner -*- C -*-
3b1e470c 2
7c0c6181
JD
3 Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007 Free Software Foundation,
4 Inc.
e9955c83
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5
6 This file is part of Bison, the GNU Compiler Compiler.
7
f16b0819 8 This program is free software: you can redistribute it and/or modify
e9955c83 9 it under the terms of the GNU General Public License as published by
f16b0819 10 the Free Software Foundation, either version 3 of the License, or
e9955c83
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11 (at your option) any later version.
12
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
17
18 You should have received a copy of the GNU General Public License
f16b0819 19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
e9955c83 20
aa418041 21%option debug nodefault nounput noyywrap never-interactive
e9955c83
AD
22%option prefix="gram_" outfile="lex.yy.c"
23
24%{
4f6e011e
PE
25/* Work around a bug in flex 2.5.31. See Debian bug 333231
26 <http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=333231>. */
27#undef gram_wrap
28#define gram_wrap() 1
29
e9071366
AD
30#define FLEX_PREFIX(Id) gram_ ## Id
31#include "flex-scanner.h"
223ff46e 32
e9955c83 33#include "complain.h"
3f2d73f1 34#include "files.h"
e9955c83 35#include "gram.h"
ca407bdf 36#include "quotearg.h"
e9955c83 37#include "reader.h"
223ff46e 38#include "uniqstr.h"
e9955c83 39
e9071366
AD
40#include <mbswidth.h>
41#include <quote.h>
42
43#include "scan-gram.h"
44
45#define YY_DECL GRAM_LEX_DECL
2346344a 46
3f2d73f1 47#define YY_USER_INIT \
e9071366 48 code_start = scanner_cursor = loc->start; \
dc9701e8 49
3f2d73f1 50/* Location of scanner cursor. */
4a678af8 51static boundary scanner_cursor;
41141c56 52
e9071366 53#define YY_USER_ACTION location_compute (loc, &scanner_cursor, yytext, yyleng);
d8d3f94a 54
6c30d641 55static size_t no_cr_read (FILE *, char *, size_t);
d8d3f94a
PE
56#define YY_INPUT(buf, result, size) ((result) = no_cr_read (yyin, buf, size))
57
7ec2d4cd 58/* A string representing the most recently saved token. */
7c0c6181 59static char *last_string;
7ec2d4cd 60
7ec2d4cd 61void
e9071366 62gram_scanner_last_string_free (void)
7ec2d4cd 63{
41141c56 64 STRING_FREE;
7ec2d4cd 65}
e9955c83 66
4517da37 67static void handle_syncline (char *, location);
1452af69 68static unsigned long int scan_integer (char const *p, int base, location loc);
d8d3f94a 69static int convert_ucn_to_byte (char const *hex_text);
aa418041 70static void unexpected_eof (boundary, char const *);
4febdd96 71static void unexpected_newline (boundary, char const *);
e9955c83
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72
73%}
e9071366
AD
74 /* A C-like comment in directives/rules. */
75%x SC_YACC_COMMENT
76 /* Strings and characters in directives/rules. */
e9955c83 77%x SC_ESCAPED_STRING SC_ESCAPED_CHARACTER
e9071366
AD
78 /* A identifier was just read in directives/rules. Special state
79 to capture the sequence `identifier :'. */
80%x SC_AFTER_IDENTIFIER
e9071366
AD
81
82 /* Three types of user code:
83 - prologue (code between `%{' `%}' in the first section, before %%);
84 - actions, printers, union, etc, (between braced in the middle section);
85 - epilogue (everything after the second %%). */
86%x SC_PROLOGUE SC_BRACED_CODE SC_EPILOGUE
87 /* C and C++ comments in code. */
88%x SC_COMMENT SC_LINE_COMMENT
89 /* Strings and characters in code. */
90%x SC_STRING SC_CHARACTER
e9955c83 91
29c01725
AD
92letter [.abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_]
93id {letter}({letter}|[0-9])*
94directive %{letter}({letter}|[0-9]|-)*
624a35e2 95int [0-9]+
d8d3f94a
PE
96
97/* POSIX says that a tag must be both an id and a C union member, but
98 historically almost any character is allowed in a tag. We disallow
99 NUL and newline, as this simplifies our implementation. */
100tag [^\0\n>]+
101
102/* Zero or more instances of backslash-newline. Following GCC, allow
103 white space between the backslash and the newline. */
104splice (\\[ \f\t\v]*\n)*
e9955c83
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105
106%%
107%{
a706a1cc 108 /* Nesting level of the current code in braces. */
5362ed19 109 int braces_level IF_LINT (= 0);
1a9e39f1 110
3f2d73f1 111 /* Parent context state, when applicable. */
5362ed19 112 int context_state IF_LINT (= 0);
a706a1cc 113
3f2d73f1 114 /* Location of most recent identifier, when applicable. */
a2bc9dbc 115 location id_loc IF_LINT (= empty_location);
3f2d73f1 116
a2bc9dbc
PE
117 /* Where containing code started, when applicable. Its initial
118 value is relevant only when yylex is invoked in the SC_EPILOGUE
119 start condition. */
120 boundary code_start = scanner_cursor;
3f2d73f1 121
223ff46e
PE
122 /* Where containing comment or string or character literal started,
123 when applicable. */
a2bc9dbc 124 boundary token_start IF_LINT (= scanner_cursor);
e9955c83
AD
125%}
126
127
3f2d73f1
PE
128 /*-----------------------.
129 | Scanning white space. |
130 `-----------------------*/
131
58d7a1a1 132<INITIAL,SC_AFTER_IDENTIFIER>
3f2d73f1 133{
4febdd96 134 /* Comments and white space. */
83adb046 135 "," warn_at (*loc, _("stray `,' treated as white space"));
4febdd96 136 [ \f\n\t\v] |
3f2d73f1 137 "//".* ;
83adb046
PE
138 "/*" {
139 token_start = loc->start;
140 context_state = YY_START;
141 BEGIN SC_YACC_COMMENT;
142 }
3f2d73f1
PE
143
144 /* #line directives are not documented, and may be withdrawn or
145 modified in future versions of Bison. */
146 ^"#line "{int}" \"".*"\"\n" {
4517da37 147 handle_syncline (yytext + sizeof "#line " - 1, *loc);
3f2d73f1
PE
148 }
149}
150
151
e9955c83
AD
152 /*----------------------------.
153 | Scanning Bison directives. |
154 `----------------------------*/
155<INITIAL>
156{
58d7a1a1 157 "%binary" return PERCENT_NONASSOC;
136a0f76 158 "%code" return PERCENT_CODE;
58d7a1a1
AD
159 "%debug" return PERCENT_DEBUG;
160 "%default"[-_]"prec" return PERCENT_DEFAULT_PREC;
161 "%define" return PERCENT_DEFINE;
162 "%defines" return PERCENT_DEFINES;
163 "%destructor" return PERCENT_DESTRUCTOR;
164 "%dprec" return PERCENT_DPREC;
165 "%error"[-_]"verbose" return PERCENT_ERROR_VERBOSE;
166 "%expect" return PERCENT_EXPECT;
167 "%expect"[-_]"rr" return PERCENT_EXPECT_RR;
168 "%file-prefix" return PERCENT_FILE_PREFIX;
e9955c83 169 "%fixed"[-_]"output"[-_]"files" return PERCENT_YACC;
58d7a1a1
AD
170 "%initial-action" return PERCENT_INITIAL_ACTION;
171 "%glr-parser" return PERCENT_GLR_PARSER;
0e021770 172 "%language" return PERCENT_LANGUAGE;
58d7a1a1
AD
173 "%left" return PERCENT_LEFT;
174 "%lex-param" return PERCENT_LEX_PARAM;
175 "%locations" return PERCENT_LOCATIONS;
176 "%merge" return PERCENT_MERGE;
177 "%name"[-_]"prefix" return PERCENT_NAME_PREFIX;
178 "%no"[-_]"default"[-_]"prec" return PERCENT_NO_DEFAULT_PREC;
179 "%no"[-_]"lines" return PERCENT_NO_LINES;
180 "%nonassoc" return PERCENT_NONASSOC;
181 "%nondeterministic-parser" return PERCENT_NONDETERMINISTIC_PARSER;
182 "%nterm" return PERCENT_NTERM;
183 "%output" return PERCENT_OUTPUT;
184 "%parse-param" return PERCENT_PARSE_PARAM;
185 "%prec" return PERCENT_PREC;
186 "%printer" return PERCENT_PRINTER;
187 "%pure"[-_]"parser" return PERCENT_PURE_PARSER;
188 "%require" return PERCENT_REQUIRE;
189 "%right" return PERCENT_RIGHT;
190 "%skeleton" return PERCENT_SKELETON;
191 "%start" return PERCENT_START;
192 "%term" return PERCENT_TOKEN;
193 "%token" return PERCENT_TOKEN;
194 "%token"[-_]"table" return PERCENT_TOKEN_TABLE;
195 "%type" return PERCENT_TYPE;
196 "%union" return PERCENT_UNION;
197 "%verbose" return PERCENT_VERBOSE;
198 "%yacc" return PERCENT_YACC;
e9955c83 199
3f2d73f1 200 {directive} {
41141c56 201 complain_at (*loc, _("invalid directive: %s"), quote (yytext));
412f8a59 202 }
900c5db5 203
e9955c83 204 "=" return EQUAL;
e9071366 205 "|" return PIPE;
e9955c83 206 ";" return SEMICOLON;
12e35840 207 "<*>" return TYPE_TAG_ANY;
3ebecc24 208 "<>" return TYPE_TAG_NONE;
e9955c83 209
3f2d73f1 210 {id} {
58d7a1a1 211 val->uniqstr = uniqstr_new (yytext);
3f2d73f1 212 id_loc = *loc;
3f2d73f1 213 BEGIN SC_AFTER_IDENTIFIER;
e9955c83
AD
214 }
215
d8d3f94a 216 {int} {
1452af69
PE
217 val->integer = scan_integer (yytext, 10, *loc);
218 return INT;
219 }
220 0[xX][0-9abcdefABCDEF]+ {
221 val->integer = scan_integer (yytext, 16, *loc);
d8d3f94a
PE
222 return INT;
223 }
e9955c83
AD
224
225 /* Characters. We don't check there is only one. */
3f2d73f1 226 "'" STRING_GROW; token_start = loc->start; BEGIN SC_ESCAPED_CHARACTER;
e9955c83
AD
227
228 /* Strings. */
ca407bdf 229 "\"" token_start = loc->start; BEGIN SC_ESCAPED_STRING;
e9955c83
AD
230
231 /* Prologue. */
3f2d73f1 232 "%{" code_start = loc->start; BEGIN SC_PROLOGUE;
e9955c83
AD
233
234 /* Code in between braces. */
3f2d73f1
PE
235 "{" {
236 STRING_GROW;
237 braces_level = 0;
238 code_start = loc->start;
239 BEGIN SC_BRACED_CODE;
240 }
e9955c83
AD
241
242 /* A type. */
d8d3f94a 243 "<"{tag}">" {
223ff46e 244 obstack_grow (&obstack_for_string, yytext + 1, yyleng - 2);
41141c56 245 STRING_FINISH;
223ff46e 246 val->uniqstr = uniqstr_new (last_string);
41141c56 247 STRING_FREE;
4cdb01db
AD
248 return TYPE;
249 }
250
a706a1cc
PE
251 "%%" {
252 static int percent_percent_count;
e9955c83 253 if (++percent_percent_count == 2)
a2bc9dbc 254 BEGIN SC_EPILOGUE;
e9955c83
AD
255 return PERCENT_PERCENT;
256 }
257
a706a1cc 258 . {
41141c56 259 complain_at (*loc, _("invalid character: %s"), quote (yytext));
3f2d73f1 260 }
379f0ac8
PE
261
262 <<EOF>> {
263 loc->start = loc->end = scanner_cursor;
264 yyterminate ();
265 }
3f2d73f1
PE
266}
267
268
269 /*-----------------------------------------------------------------.
270 | Scanning after an identifier, checking whether a colon is next. |
271 `-----------------------------------------------------------------*/
272
273<SC_AFTER_IDENTIFIER>
274{
275 ":" {
3f2d73f1
PE
276 *loc = id_loc;
277 BEGIN INITIAL;
278 return ID_COLON;
279 }
280 . {
281 scanner_cursor.column -= mbsnwidth (yytext, yyleng, 0);
282 yyless (0);
283 *loc = id_loc;
284 BEGIN INITIAL;
285 return ID;
286 }
287 <<EOF>> {
288 *loc = id_loc;
289 BEGIN INITIAL;
290 return ID;
e9955c83
AD
291 }
292}
293
294
d8d3f94a
PE
295 /*---------------------------------------------------------------.
296 | Scanning a Yacc comment. The initial `/ *' is already eaten. |
297 `---------------------------------------------------------------*/
e9955c83 298
d8d3f94a 299<SC_YACC_COMMENT>
e9955c83 300{
3f2d73f1 301 "*/" BEGIN context_state;
a706a1cc 302 .|\n ;
aa418041 303 <<EOF>> unexpected_eof (token_start, "*/"); BEGIN context_state;
d8d3f94a
PE
304}
305
306
307 /*------------------------------------------------------------.
308 | Scanning a C comment. The initial `/ *' is already eaten. |
309 `------------------------------------------------------------*/
310
311<SC_COMMENT>
312{
3f2d73f1 313 "*"{splice}"/" STRING_GROW; BEGIN context_state;
aa418041 314 <<EOF>> unexpected_eof (token_start, "*/"); BEGIN context_state;
e9955c83
AD
315}
316
317
d8d3f94a
PE
318 /*--------------------------------------------------------------.
319 | Scanning a line comment. The initial `//' is already eaten. |
320 `--------------------------------------------------------------*/
321
322<SC_LINE_COMMENT>
323{
3f2d73f1 324 "\n" STRING_GROW; BEGIN context_state;
41141c56 325 {splice} STRING_GROW;
3f2d73f1 326 <<EOF>> BEGIN context_state;
d8d3f94a
PE
327}
328
329
4febdd96
PE
330 /*------------------------------------------------.
331 | Scanning a Bison string, including its escapes. |
332 | The initial quote is already eaten. |
333 `------------------------------------------------*/
e9955c83
AD
334
335<SC_ESCAPED_STRING>
336{
47aee066
JD
337 "\""|"\n" {
338 if (yytext[0] == '\n')
339 unexpected_newline (token_start, "\"");
340 STRING_FINISH;
341 loc->start = token_start;
342 val->chars = last_string;
343 BEGIN INITIAL;
344 return STRING;
345 }
346 <<EOF>> {
347 unexpected_eof (token_start, "\"");
41141c56 348 STRING_FINISH;
3f2d73f1 349 loc->start = token_start;
223ff46e 350 val->chars = last_string;
a706a1cc 351 BEGIN INITIAL;
e9955c83
AD
352 return STRING;
353 }
e9955c83
AD
354}
355
4febdd96
PE
356 /*----------------------------------------------------------.
357 | Scanning a Bison character literal, decoding its escapes. |
358 | The initial quote is already eaten. |
359 `----------------------------------------------------------*/
e9955c83
AD
360
361<SC_ESCAPED_CHARACTER>
362{
47aee066
JD
363 "'"|"\n" {
364 if (yytext[0] == '\n')
365 unexpected_newline (token_start, "'");
41141c56
PE
366 STRING_GROW;
367 STRING_FINISH;
3f2d73f1 368 loc->start = token_start;
58d7a1a1 369 val->character = last_string[1];
41141c56 370 STRING_FREE;
a706a1cc 371 BEGIN INITIAL;
58d7a1a1 372 return CHAR;
e9955c83 373 }
47aee066
JD
374 <<EOF>> {
375 unexpected_eof (token_start, "'");
376 STRING_FINISH;
377 loc->start = token_start;
378 if (strlen(last_string) > 1)
379 val->character = last_string[1];
380 else
381 val->character = last_string[0];
382 STRING_FREE;
383 BEGIN INITIAL;
384 return CHAR;
385 }
4febdd96 386}
a706a1cc 387
4febdd96
PE
388<SC_ESCAPED_CHARACTER,SC_ESCAPED_STRING>
389{
92ac3705 390 \0 complain_at (*loc, _("invalid null character"));
e9955c83
AD
391}
392
393
394 /*----------------------------.
395 | Decode escaped characters. |
396 `----------------------------*/
397
398<SC_ESCAPED_STRING,SC_ESCAPED_CHARACTER>
399{
d8d3f94a 400 \\[0-7]{1,3} {
4517da37 401 unsigned long int c = strtoul (yytext + 1, NULL, 8);
d8d3f94a 402 if (UCHAR_MAX < c)
3f2d73f1 403 complain_at (*loc, _("invalid escape sequence: %s"), quote (yytext));
05ac60f3 404 else if (! c)
92ac3705 405 complain_at (*loc, _("invalid null character: %s"), quote (yytext));
e9955c83 406 else
223ff46e 407 obstack_1grow (&obstack_for_string, c);
e9955c83
AD
408 }
409
6b0d38ab 410 \\x[0-9abcdefABCDEF]+ {
4517da37
PE
411 verify (UCHAR_MAX < ULONG_MAX);
412 unsigned long int c = strtoul (yytext + 2, NULL, 16);
413 if (UCHAR_MAX < c)
3f2d73f1 414 complain_at (*loc, _("invalid escape sequence: %s"), quote (yytext));
92ac3705
PE
415 else if (! c)
416 complain_at (*loc, _("invalid null character: %s"), quote (yytext));
d8d3f94a 417 else
223ff46e 418 obstack_1grow (&obstack_for_string, c);
e9955c83
AD
419 }
420
223ff46e
PE
421 \\a obstack_1grow (&obstack_for_string, '\a');
422 \\b obstack_1grow (&obstack_for_string, '\b');
423 \\f obstack_1grow (&obstack_for_string, '\f');
424 \\n obstack_1grow (&obstack_for_string, '\n');
425 \\r obstack_1grow (&obstack_for_string, '\r');
426 \\t obstack_1grow (&obstack_for_string, '\t');
427 \\v obstack_1grow (&obstack_for_string, '\v');
412f8a59
PE
428
429 /* \\[\"\'?\\] would be shorter, but it confuses xgettext. */
223ff46e 430 \\("\""|"'"|"?"|"\\") obstack_1grow (&obstack_for_string, yytext[1]);
412f8a59 431
6b0d38ab 432 \\(u|U[0-9abcdefABCDEF]{4})[0-9abcdefABCDEF]{4} {
d8d3f94a
PE
433 int c = convert_ucn_to_byte (yytext);
434 if (c < 0)
3f2d73f1 435 complain_at (*loc, _("invalid escape sequence: %s"), quote (yytext));
92ac3705
PE
436 else if (! c)
437 complain_at (*loc, _("invalid null character: %s"), quote (yytext));
d8d3f94a 438 else
223ff46e 439 obstack_1grow (&obstack_for_string, c);
d8d3f94a 440 }
4f25ebb0 441 \\(.|\n) {
3f2d73f1 442 complain_at (*loc, _("unrecognized escape sequence: %s"), quote (yytext));
41141c56 443 STRING_GROW;
e9955c83
AD
444 }
445}
446
4febdd96
PE
447 /*--------------------------------------------.
448 | Scanning user-code characters and strings. |
449 `--------------------------------------------*/
e9955c83 450
4febdd96
PE
451<SC_CHARACTER,SC_STRING>
452{
e9071366 453 {splice}|\\{splice}[^\n\[\]] STRING_GROW;
4febdd96 454}
e9955c83
AD
455
456<SC_CHARACTER>
457{
4febdd96
PE
458 "'" STRING_GROW; BEGIN context_state;
459 \n unexpected_newline (token_start, "'"); BEGIN context_state;
460 <<EOF>> unexpected_eof (token_start, "'"); BEGIN context_state;
e9955c83
AD
461}
462
e9955c83
AD
463<SC_STRING>
464{
4febdd96
PE
465 "\"" STRING_GROW; BEGIN context_state;
466 \n unexpected_newline (token_start, "\""); BEGIN context_state;
467 <<EOF>> unexpected_eof (token_start, "\""); BEGIN context_state;
e9955c83
AD
468}
469
470
471 /*---------------------------------------------------.
472 | Strings, comments etc. can be found in user code. |
473 `---------------------------------------------------*/
474
475<SC_BRACED_CODE,SC_PROLOGUE,SC_EPILOGUE>
476{
3f2d73f1
PE
477 "'" {
478 STRING_GROW;
479 context_state = YY_START;
480 token_start = loc->start;
481 BEGIN SC_CHARACTER;
482 }
483 "\"" {
484 STRING_GROW;
485 context_state = YY_START;
486 token_start = loc->start;
487 BEGIN SC_STRING;
488 }
489 "/"{splice}"*" {
490 STRING_GROW;
491 context_state = YY_START;
492 token_start = loc->start;
493 BEGIN SC_COMMENT;
494 }
495 "/"{splice}"/" {
496 STRING_GROW;
497 context_state = YY_START;
498 BEGIN SC_LINE_COMMENT;
499 }
e9955c83
AD
500}
501
502
624a35e2 503
58d7a1a1
AD
504 /*-----------------------------------------------------------.
505 | Scanning some code in braces (actions). The initial "{" is |
506 | already eaten. |
507 `-----------------------------------------------------------*/
e9955c83
AD
508
509<SC_BRACED_CODE>
510{
41141c56
PE
511 "{"|"<"{splice}"%" STRING_GROW; braces_level++;
512 "%"{splice}">" STRING_GROW; braces_level--;
e9955c83 513 "}" {
25522739
PE
514 obstack_1grow (&obstack_for_string, '}');
515
2346344a
AD
516 --braces_level;
517 if (braces_level < 0)
e9955c83 518 {
41141c56 519 STRING_FINISH;
3f2d73f1 520 loc->start = code_start;
eb095650 521 val->code = last_string;
a706a1cc 522 BEGIN INITIAL;
58d7a1a1 523 return BRACED_CODE;
e9955c83
AD
524 }
525 }
526
a706a1cc
PE
527 /* Tokenize `<<%' correctly (as `<<' `%') rather than incorrrectly
528 (as `<' `<%'). */
41141c56 529 "<"{splice}"<" STRING_GROW;
a706a1cc 530
47aee066
JD
531 <<EOF>> {
532 unexpected_eof (code_start, "}");
533 STRING_FINISH;
534 loc->start = code_start;
eb095650 535 val->code = last_string;
47aee066
JD
536 BEGIN INITIAL;
537 return BRACED_CODE;
538 }
e9955c83
AD
539}
540
541
542 /*--------------------------------------------------------------.
543 | Scanning some prologue: from "%{" (already scanned) to "%}". |
544 `--------------------------------------------------------------*/
545
546<SC_PROLOGUE>
547{
548 "%}" {
41141c56 549 STRING_FINISH;
3f2d73f1 550 loc->start = code_start;
223ff46e 551 val->chars = last_string;
a706a1cc 552 BEGIN INITIAL;
e9955c83
AD
553 return PROLOGUE;
554 }
555
47aee066
JD
556 <<EOF>> {
557 unexpected_eof (code_start, "%}");
558 STRING_FINISH;
559 loc->start = code_start;
560 val->chars = last_string;
561 BEGIN INITIAL;
562 return PROLOGUE;
563 }
e9955c83
AD
564}
565
566
567 /*---------------------------------------------------------------.
568 | Scanning the epilogue (everything after the second "%%", which |
d8d3f94a 569 | has already been eaten). |
e9955c83
AD
570 `---------------------------------------------------------------*/
571
572<SC_EPILOGUE>
573{
e9955c83 574 <<EOF>> {
41141c56 575 STRING_FINISH;
3f2d73f1 576 loc->start = code_start;
223ff46e 577 val->chars = last_string;
a706a1cc 578 BEGIN INITIAL;
e9955c83
AD
579 return EPILOGUE;
580 }
581}
582
583
4febdd96
PE
584 /*-----------------------------------------------------.
585 | By default, grow the string obstack with the input. |
586 `-----------------------------------------------------*/
587
588<SC_COMMENT,SC_LINE_COMMENT,SC_BRACED_CODE,SC_PROLOGUE,SC_EPILOGUE,SC_STRING,SC_CHARACTER,SC_ESCAPED_STRING,SC_ESCAPED_CHARACTER>. |
589<SC_COMMENT,SC_LINE_COMMENT,SC_BRACED_CODE,SC_PROLOGUE,SC_EPILOGUE>\n STRING_GROW;
590
e9955c83
AD
591%%
592
6c30d641
PE
593/* Read bytes from FP into buffer BUF of size SIZE. Return the
594 number of bytes read. Remove '\r' from input, treating \r\n
595 and isolated \r as \n. */
596
597static size_t
598no_cr_read (FILE *fp, char *buf, size_t size)
599{
a737b216
PE
600 size_t bytes_read = fread (buf, 1, size, fp);
601 if (bytes_read)
6c30d641 602 {
a737b216 603 char *w = memchr (buf, '\r', bytes_read);
6c30d641
PE
604 if (w)
605 {
606 char const *r = ++w;
a737b216 607 char const *lim = buf + bytes_read;
6c30d641
PE
608
609 for (;;)
610 {
611 /* Found an '\r'. Treat it like '\n', but ignore any
612 '\n' that immediately follows. */
613 w[-1] = '\n';
614 if (r == lim)
615 {
616 int ch = getc (fp);
617 if (ch != '\n' && ungetc (ch, fp) != ch)
618 break;
619 }
620 else if (*r == '\n')
621 r++;
622
623 /* Copy until the next '\r'. */
624 do
625 {
626 if (r == lim)
627 return w - buf;
628 }
629 while ((*w++ = *r++) != '\r');
630 }
631
632 return w - buf;
633 }
634 }
635
a737b216 636 return bytes_read;
6c30d641
PE
637}
638
639
f25bfb75 640
1452af69
PE
641/*------------------------------------------------------.
642| Scan NUMBER for a base-BASE integer at location LOC. |
643`------------------------------------------------------*/
644
645static unsigned long int
646scan_integer (char const *number, int base, location loc)
647{
4517da37
PE
648 verify (INT_MAX < ULONG_MAX);
649 unsigned long int num = strtoul (number, NULL, base);
650
651 if (INT_MAX < num)
1452af69
PE
652 {
653 complain_at (loc, _("integer out of range: %s"), quote (number));
654 num = INT_MAX;
655 }
4517da37 656
1452af69
PE
657 return num;
658}
659
660
d8d3f94a
PE
661/*------------------------------------------------------------------.
662| Convert universal character name UCN to a single-byte character, |
663| and return that character. Return -1 if UCN does not correspond |
664| to a single-byte character. |
665`------------------------------------------------------------------*/
666
667static int
668convert_ucn_to_byte (char const *ucn)
669{
4517da37
PE
670 verify (UCHAR_MAX <= INT_MAX);
671 unsigned long int code = strtoul (ucn + 2, NULL, 16);
d8d3f94a
PE
672
673 /* FIXME: Currently we assume Unicode-compatible unibyte characters
674 on ASCII hosts (i.e., Latin-1 on hosts with 8-bit bytes). On
675 non-ASCII hosts we support only the portable C character set.
676 These limitations should be removed once we add support for
677 multibyte characters. */
678
679 if (UCHAR_MAX < code)
680 return -1;
681
682#if ! ('$' == 0x24 && '@' == 0x40 && '`' == 0x60 && '~' == 0x7e)
683 {
684 /* A non-ASCII host. Use CODE to index into a table of the C
685 basic execution character set, which is guaranteed to exist on
686 all Standard C platforms. This table also includes '$', '@',
8e6ef483 687 and '`', which are not in the basic execution character set but
d8d3f94a
PE
688 which are unibyte characters on all the platforms that we know
689 about. */
690 static signed char const table[] =
691 {
692 '\0', -1, -1, -1, -1, -1, -1, '\a',
693 '\b', '\t', '\n', '\v', '\f', '\r', -1, -1,
694 -1, -1, -1, -1, -1, -1, -1, -1,
695 -1, -1, -1, -1, -1, -1, -1, -1,
696 ' ', '!', '"', '#', '$', '%', '&', '\'',
697 '(', ')', '*', '+', ',', '-', '.', '/',
698 '0', '1', '2', '3', '4', '5', '6', '7',
699 '8', '9', ':', ';', '<', '=', '>', '?',
700 '@', 'A', 'B', 'C', 'D', 'E', 'F', 'G',
701 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O',
702 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W',
703 'X', 'Y', 'Z', '[', '\\', ']', '^', '_',
704 '`', 'a', 'b', 'c', 'd', 'e', 'f', 'g',
705 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o',
706 'p', 'q', 'r', 's', 't', 'u', 'v', 'w',
707 'x', 'y', 'z', '{', '|', '}', '~'
708 };
709
710 code = code < sizeof table ? table[code] : -1;
711 }
712#endif
c4d720cd 713
d8d3f94a
PE
714 return code;
715}
716
717
900c5db5
AD
718/*----------------------------------------------------------------.
719| Handle `#line INT "FILE"'. ARGS has already skipped `#line '. |
720`----------------------------------------------------------------*/
721
722static void
4517da37 723handle_syncline (char *args, location loc)
900c5db5 724{
4517da37
PE
725 char *after_num;
726 unsigned long int lineno = strtoul (args, &after_num, 10);
727 char *file = strchr (after_num, '"') + 1;
728 *strchr (file, '"') = '\0';
729 if (INT_MAX <= lineno)
730 {
731 warn_at (loc, _("line number overflow"));
732 lineno = INT_MAX;
733 }
e9071366 734 current_file = uniqstr_new (file);
0c8e079f 735 boundary_set (&scanner_cursor, current_file, lineno, 1);
4517da37
PE
736}
737
738
4febdd96
PE
739/*----------------------------------------------------------------.
740| For a token or comment starting at START, report message MSGID, |
741| which should say that an end marker was found before |
742| the expected TOKEN_END. |
743`----------------------------------------------------------------*/
744
745static void
746unexpected_end (boundary start, char const *msgid, char const *token_end)
747{
748 location loc;
749 loc.start = start;
750 loc.end = scanner_cursor;
751 complain_at (loc, _(msgid), token_end);
752}
753
754
3f2d73f1
PE
755/*------------------------------------------------------------------------.
756| Report an unexpected EOF in a token or comment starting at START. |
757| An end of file was encountered and the expected TOKEN_END was missing. |
3f2d73f1 758`------------------------------------------------------------------------*/
a706a1cc
PE
759
760static void
aa418041 761unexpected_eof (boundary start, char const *token_end)
a706a1cc 762{
4febdd96
PE
763 unexpected_end (start, N_("missing `%s' at end of file"), token_end);
764}
765
766
767/*----------------------------------------.
768| Likewise, but for unexpected newlines. |
769`----------------------------------------*/
770
771static void
772unexpected_newline (boundary start, char const *token_end)
773{
774 unexpected_end (start, N_("missing `%s' at end of line"), token_end);
a706a1cc
PE
775}
776
777
f25bfb75
AD
778/*-------------------------.
779| Initialize the scanner. |
780`-------------------------*/
781
1d6412ad 782void
e9071366 783gram_scanner_initialize (void)
1d6412ad 784{
223ff46e 785 obstack_init (&obstack_for_string);
1d6412ad
AD
786}
787
788
f25bfb75
AD
789/*-----------------------------------------------.
790| Free all the memory allocated to the scanner. |
791`-----------------------------------------------*/
792
4cdb01db 793void
e9071366 794gram_scanner_free (void)
4cdb01db 795{
223ff46e 796 obstack_free (&obstack_for_string, 0);
536545f3 797 /* Reclaim Flex's buffers. */
580b8926 798 yylex_destroy ();
4cdb01db 799}