chiark - git - fanf - unifdef.git/blob

1 /*

3 *

4 * Redistribution and use in source and binary forms, with or without

5 * modification, are permitted provided that the following conditions

6 * are met:

7 * 1. Redistributions of source code must retain the above copyright

8 * notice, this list of conditions and the following disclaimer.

9 * 2. Redistributions in binary form must reproduce the above copyright

10 * notice, this list of conditions and the following disclaimer in the

11 * documentation and/or other materials provided with the distribution.

12 *

13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND

14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

16 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE

17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

23 * SUCH DAMAGE.

24 */

25

26 /*

27 * unifdef - remove ifdef'ed lines

28 *

29 * This code was derived from software contributed to Berkeley by Dave Yost.

30 * It was rewritten to support ANSI C by Tony Finch. The original version

31 * of unifdef carried the 4-clause BSD copyright licence. None of its code

32 * remains in this version (though some of the names remain) so it now

33 * carries a more liberal licence.

34 *

35 * Wishlist:

36 * provide an option which will append the name of the

37 * appropriate symbol after #else's and #endif's

38 * provide an option which will check symbols after

39 * #else's and #endif's to see that they match their

40 * corresponding #ifdef or #ifndef

41 *

42 * These require better buffer handling, which would also make

43 * it possible to handle all "dodgy" directives correctly.

44 */

45

46 #include "unifdef.h"

47

48 static const char copyright[] =

49 #include "version.h"

50 "@(#) $Author: Tony Finch (dot@dotat.at) $\n"

51 "@(#) $URL: http://dotat.at/prog/unifdef $\n"

52 ;

53

54 /* types of input lines: */

55 typedef enum {

56 LT_TRUEI, /* a true #if with ignore flag */

57 LT_FALSEI, /* a false #if with ignore flag */

58 LT_IF, /* an unknown #if */

59 LT_TRUE, /* a true #if */

60 LT_FALSE, /* a false #if */

61 LT_ELIF, /* an unknown #elif */

62 LT_ELTRUE, /* a true #elif */

63 LT_ELFALSE, /* a false #elif */

64 LT_ELSE, /* #else */

65 LT_ENDIF, /* #endif */

66 LT_DODGY, /* flag: directive is not on one line */

67 LT_DODGY_LAST = LT_DODGY + LT_ENDIF,

68 LT_PLAIN, /* ordinary line */

69 LT_EOF, /* end of file */

70 LT_ERROR, /* unevaluable #if */

71 LT_COUNT

72 } Linetype;

73

74 static char const * const linetype_name[] = {

75 "TRUEI", "FALSEI", "IF", "TRUE", "FALSE",

76 "ELIF", "ELTRUE", "ELFALSE", "ELSE", "ENDIF",

77 "DODGY TRUEI", "DODGY FALSEI",

78 "DODGY IF", "DODGY TRUE", "DODGY FALSE",

79 "DODGY ELIF", "DODGY ELTRUE", "DODGY ELFALSE",

80 "DODGY ELSE", "DODGY ENDIF",

81 "PLAIN", "EOF", "ERROR"

82 };

83

84 #define linetype_if2elif(lt) ((Linetype)(lt - LT_IF + LT_ELIF))

85 #define linetype_2dodgy(lt) ((Linetype)(lt + LT_DODGY))

86

87 /* state of #if processing */

88 typedef enum {

89 IS_OUTSIDE,

90 IS_FALSE_PREFIX, /* false #if followed by false #elifs */

91 IS_TRUE_PREFIX, /* first non-false #(el)if is true */

92 IS_PASS_MIDDLE, /* first non-false #(el)if is unknown */

93 IS_FALSE_MIDDLE, /* a false #elif after a pass state */

94 IS_TRUE_MIDDLE, /* a true #elif after a pass state */

95 IS_PASS_ELSE, /* an else after a pass state */

96 IS_FALSE_ELSE, /* an else after a true state */

97 IS_TRUE_ELSE, /* an else after only false states */

98 IS_FALSE_TRAILER, /* #elifs after a true are false */

99 IS_COUNT

100 } Ifstate;

101

102 static char const * const ifstate_name[] = {

103 "OUTSIDE", "FALSE_PREFIX", "TRUE_PREFIX",

104 "PASS_MIDDLE", "FALSE_MIDDLE", "TRUE_MIDDLE",

105 "PASS_ELSE", "FALSE_ELSE", "TRUE_ELSE",

106 "FALSE_TRAILER"

107 };

108

109 /* state of comment parser */

110 typedef enum {

111 NO_COMMENT = false, /* outside a comment */

112 C_COMMENT, /* in a comment like this one */

113 CXX_COMMENT, /* between // and end of line */

114 STARTING_COMMENT, /* just after slash-backslash-newline */

115 FINISHING_COMMENT, /* star-backslash-newline in a C comment */

116 CHAR_LITERAL, /* inside '' */

117 STRING_LITERAL, /* inside "" */

118 RAW_STRING_LITERAL /* inside R"()" */

119 } Comment_state;

120

121 static char const * const comment_name[] = {

122 "NO", "C", "CXX", "STARTING", "FINISHING", "CHAR", "STRING"

123 };

124

125 /* state of preprocessor line parser */

126 typedef enum {

127 LS_START, /* only space and comments on this line */

128 LS_HASH, /* only space, comments, and a hash */

129 LS_DIRTY /* this line can't be a preprocessor line */

130 } Line_state;

131

132 static char const * const linestate_name[] = {

133 "START", "HASH", "DIRTY"

134 };

135

136 /*

137 * Minimum translation limits from ISO/IEC 9899:1999 5.2.4.1

138 */

139 #define MAXDEPTH 64 /* maximum #if nesting */

140 #define MAXLINE 4096 /* maximum length of line */

141 #define MAXSYMS 16384 /* maximum number of symbols */

142

143 /*

144 * Sometimes when editing a keyword the replacement text is longer, so

145 * we leave some space at the end of the tline buffer to accommodate this.

146 */

147 #define EDITSLOP 10

148

149 /*

150 * Globals.

151 */

152

153 static bool compblank; /* -B: compress blank lines */

154 static bool lnblank; /* -b: blank deleted lines */

155 static bool complement; /* -c: do the complement */

156 static bool debugging; /* -d: debugging reports */

157 static bool inplace; /* -m: modify in place */

158 static bool iocccok; /* -e: fewer IOCCC errors */

159 static bool strictlogic; /* -K: keep ambiguous #ifs */

160 static bool killconsts; /* -k: eval constant #ifs */

161 static bool lnnum; /* -n: add #line directives */

162 static bool symlist; /* -s: output symbol list */

163 static bool symdepth; /* -S: output symbol depth */

164 static bool text; /* -t: this is a text file */

165

166 static const char *symname[MAXSYMS]; /* symbol name */

167 static const char *value[MAXSYMS]; /* -Dsym=value */

168 static bool ignore[MAXSYMS]; /* -iDsym or -iUsym */

169 static int nsyms; /* number of symbols */

170

171 static FILE *input; /* input file pointer */

172 static const char *filename; /* input file name */

173 static int linenum; /* current line number */

174 static const char *linefile; /* file name for #line */

175 static FILE *output; /* output file pointer */

176 static const char *ofilename; /* output file name */

177 static const char *backext; /* backup extension */

178 static char *tempname; /* avoid splatting input */

179

180 static char tline[MAXLINE+EDITSLOP];/* input buffer plus space */

181 static char *keyword; /* used for editing #elif's */

182

183 /*

184 * When processing a file, the output's newline style will match the

185 * input's, and unifdef correctly handles CRLF or LF endings whatever

186 * the platform's native style. The stdio streams are opened in binary

187 * mode to accommodate platforms whose native newline style is CRLF.

188 * When the output isn't a processed input file (when it is error /

189 * debug / diagnostic messages) then unifdef uses native line endings.

190 */

191

192 static const char *newline; /* input file format */

193 static const char newline_unix[] = "\n";

194 static const char newline_crlf[] = "\r\n";

195

196 static Comment_state incomment; /* comment parser state */

197 static Line_state linestate; /* #if line parser state */

198 static Ifstate ifstate[MAXDEPTH]; /* #if processor state */

199 static bool ignoring[MAXDEPTH]; /* ignore comments state */

200 static int stifline[MAXDEPTH]; /* start of current #if */

201 static int depth; /* current #if nesting */

202 static int delcount; /* count of deleted lines */

203 static unsigned blankcount; /* count of blank lines */

204 static unsigned blankmax; /* maximum recent blankcount */

205 static bool constexpr; /* constant #if expression */

206 static bool zerosyms; /* to format symdepth output */

207 static bool firstsym; /* ditto */

208

209 static int exitmode; /* exit status mode */

210 static int exitstat; /* program exit status */

211 static bool altered; /* was this file modified? */

212

213 static void addsym1(bool, bool, char *);

214 static void addsym2(bool, const char *, const char *);

215 static char *astrcat(const char *, const char *);

216 static void cleantemp(void);

217 static void closeio(void);

218 static void debug(const char *, ...);

219 static void debugsym(const char *, int);

220 static bool defundef(void);

221 static void defundefile(const char *);

222 static void done(void);

223 static void error(const char *);

224 static int findsym(const char **);

225 static void flushline(bool);

226 static void hashline(void);

227 static void help(void);

228 static Linetype ifeval(const char **);

229 static void ignoreoff(void);

230 static void ignoreon(void);

231 static void indirectsym(void);

232 static void keywordedit(const char *);

233 static const char *matchsym(const char *, const char *);

234 static void nest(void);

235 static Linetype parseline(void);

236 static void process(void);

237 static void processinout(const char *, const char *);

238 static const char *skipargs(const char *);

239 static const char *skipcomment(const char *);

240 static const char *skiphash(void);

241 static const char *skipline(const char *);

242 static const char *skipsym(const char *);

243 static void state(Ifstate);

244 static void unnest(void);

245 static void usage(void);

246 static void version(void);

247 static const char *xstrdup(const char *, const char *);

248

249 #define endsym(c) (!isalnum((unsigned char)c) && c != '_')

250

251 /*

252 * The main program.

253 */

254 int

255 main(int argc, char *argv[])

256 {

257 int opt;

258

259 while ((opt = getopt(argc, argv, "i:D:U:f:I:M:o:x:bBcdehKklmnsStV")) != -1)

260 switch (opt) {

261 case 'i': /* treat stuff controlled by these symbols as text */

262 /*

263 * For strict backwards-compatibility the U or D

264 * should be immediately after the -i but it doesn't

265 * matter much if we relax that requirement.

266 */

267 opt = *optarg++;

268 if (opt == 'D')

269 addsym1(true, true, optarg);

270 else if (opt == 'U')

271 addsym1(true, false, optarg);

272 else

273 usage();

274 break;

275 case 'D': /* define a symbol */

276 addsym1(false, true, optarg);

277 break;

278 case 'U': /* undef a symbol */

279 addsym1(false, false, optarg);

280 break;

281 case 'I': /* no-op for compatibility with cpp */

282 break;

283 case 'b': /* blank deleted lines instead of omitting them */

284 case 'l': /* backwards compatibility */

285 lnblank = true;

286 break;

287 case 'B': /* compress blank lines around removed section */

288 compblank = true;

289 break;

290 case 'c': /* treat -D as -U and vice versa */

291 complement = true;

292 break;

293 case 'd':

294 debugging = true;

295 break;

296 case 'e': /* fewer errors from dodgy lines */

297 iocccok = true;

298 break;

299 case 'f': /* definitions file */

300 defundefile(optarg);

301 break;

302 case 'h':

303 help();

304 break;

305 case 'K': /* keep ambiguous #ifs */

306 strictlogic = true;

307 break;

308 case 'k': /* process constant #ifs */

309 killconsts = true;

310 break;

311 case 'm': /* modify in place */

312 inplace = true;

313 break;

314 case 'M': /* modify in place and keep backup */

315 inplace = true;

316 if (strlen(optarg) > 0)

317 backext = optarg;

318 break;

319 case 'n': /* add #line directive after deleted lines */

320 lnnum = true;

321 break;

322 case 'o': /* output to a file */

323 ofilename = optarg;

324 break;

325 case 's': /* only output list of symbols that control #ifs */

326 symlist = true;

327 break;

328 case 'S': /* list symbols with their nesting depth */

329 symlist = symdepth = true;

330 break;

331 case 't': /* don't parse C comments */

332 text = true;

333 break;

334 case 'V':

335 version();

336 break;

337 case 'x':

338 exitmode = atoi(optarg);

339 if(exitmode < 0 || exitmode > 2)

340 usage();

341 break;

342 default:

343 usage();

344 }

345 argc -= optind;

346 argv += optind;

347 if (compblank && lnblank)

348 errx(2, "-B and -b are mutually exclusive");

349 if (symlist && (ofilename != NULL || inplace || argc > 1))

350 errx(2, "-s only works with one input file");

351 if (argc > 1 && ofilename != NULL)

352 errx(2, "-o cannot be used with multiple input files");

353 if (argc > 1 && !inplace)

354 errx(2, "multiple input files require -m or -M");

355 if (argc == 0 && inplace)

356 errx(2, "-m requires an input file");

357 if (argc == 0)

358 argc = 1;

359 if (argc == 1 && !inplace && ofilename == NULL)

360 ofilename = "-";

361 indirectsym();

362

363 atexit(cleantemp);

364 if (ofilename != NULL)

365 processinout(*argv, ofilename);

366 else while (argc-- > 0) {

367 processinout(*argv, *argv);

368 argv++;

369 }

370 switch(exitmode) {

371 case(0): exit(exitstat);

372 case(1): exit(!exitstat);

373 case(2): exit(0);

374 default: abort(); /* bug */

375 }

376 }

377

378 /*

379 * File logistics.

380 */

381 static void

382 processinout(const char *ifn, const char *ofn)

383 {

384 struct stat st;

385

386 if (ifn == NULL || strcmp(ifn, "-") == 0) {

387 filename = "[stdin]";

388 linefile = NULL;

389 input = fbinmode(stdin);

390 } else {

391 filename = ifn;

392 linefile = ifn;

393 input = fopen(ifn, "rb");

394 if (input == NULL)

395 err(2, "can't open %s", ifn);

396 }

397 if (strcmp(ofn, "-") == 0) {

398 output = fbinmode(stdout);

399 process();

400 return;

401 }

402 if (stat(ofn, &st) < 0) {

403 output = fopen(ofn, "wb");

404 if (output == NULL)

405 err(2, "can't create %s", ofn);

406 process();

407 return;

408 }

409

410 tempname = astrcat(ofn, ".XXXXXX");

411 output = mktempmode(tempname, st.st_mode);

412 if (output == NULL)

413 err(2, "can't create %s", tempname);

414

415 process();

416

417 if (backext != NULL) {

418 char *backname = astrcat(ofn, backext);

419 if (rename(ofn, backname) < 0)

420 err(2, "can't rename \"%s\" to \"%s\"", ofn, backname);

421 free(backname);

422 }

423 /* leave file unmodified if unifdef made no changes */

424 if (!altered && backext == NULL) {

425 if (remove(tempname) < 0)

426 warn("can't remove \"%s\"", tempname);

427 } else if (replace(tempname, ofn) < 0)

428 err(2, "can't rename \"%s\" to \"%s\"", tempname, ofn);

429 free(tempname);

430 tempname = NULL;

431 }

432

433 /*

434 * For cleaning up if there is an error.

435 */

436 static void

437 cleantemp(void)

438 {

439 if (tempname != NULL)

440 remove(tempname);

441 }

442

443 /*

444 * Self-identification functions.

445 */

446

447 static void

448 version(void)

449 {

450 const char *c = copyright;

451 for (;;) {

452 while (*++c != '$')

453 if (*c == '\0')

454 exit(0);

455 while (*++c != '$')

456 putc(*c, stderr);

457 putc('\n', stderr);

458 }

459 }

460

461 static void

462 synopsis(FILE *fp)

463 {

464 fprintf(fp,

465 "usage: unifdef [-bBcdehKkmnsStV] [-x{012}] [-Mext] [-opath] \\\n"

466 " [-[i]Dsym[=val]] [-[i]Usym] [-fpath] ... [file] ...\n");

467 }

468

469 static void

470 usage(void)

471 {

472 synopsis(stderr);

473 exit(2);

474 }

475

476 static void

477 help(void)

478 {

479 synopsis(stdout);

480 printf(

481 " -Dsym=val define preprocessor symbol with given value\n"

482 " -Dsym define preprocessor symbol with value 1\n"

483 " -Usym preprocessor symbol is undefined\n"

484 " -iDsym=val \\ ignore C strings and comments\n"

485 " -iDsym ) in sections controlled by these\n"

486 " -iUsym / preprocessor symbols\n"

487 " -fpath file containing #define and #undef directives\n"

488 " -b blank lines instead of deleting them\n"

489 " -B compress blank lines around deleted section\n"

490 " -c complement (invert) keep vs. delete\n"

491 " -d debugging mode\n"

492 " -e ignore multiline preprocessor directives\n"

493 " -h print help\n"

494 " -Ipath extra include file path (ignored)\n"

495 " -K disable && and || short-circuiting\n"

496 " -k process constant #if expressions\n"

497 " -Mext modify in place and keep backups\n"

498 " -m modify input files in place\n"

499 " -n add #line directives to output\n"

500 " -opath output file name\n"

501 " -S list #if control symbols with nesting\n"

502 " -s list #if control symbols\n"

503 " -t ignore C strings and comments\n"

504 " -V print version\n"

505 " -x{012} exit status mode\n"

506 );

507 exit(0);

508 }

509

510 /*

511 * A state transition function alters the global #if processing state

512 * in a particular way. The table below is indexed by the current

513 * processing state and the type of the current line.

514 *

515 * Nesting is handled by keeping a stack of states; some transition

516 * functions increase or decrease the depth. They also maintain the

517 * ignore state on a stack. In some complicated cases they have to

518 * alter the preprocessor directive, as follows.

519 *

520 * When we have processed a group that starts off with a known-false

521 * #if/#elif sequence (which has therefore been deleted) followed by a

522 * #elif that we don't understand and therefore must keep, we edit the

523 * latter into a #if to keep the nesting correct. We use memcpy() to

524 * overwrite the 4 byte token "elif" with "if " without a '\0' byte.

525 *

526 * When we find a true #elif in a group, the following block will

527 * always be kept and the rest of the sequence after the next #elif or

528 * #else will be discarded. We edit the #elif into a #else and the

529 * following directive to #endif since this has the desired behaviour.

530 *

531 * "Dodgy" directives are split across multiple lines, the most common

532 * example being a multi-line comment hanging off the right of the

533 * directive. We can handle them correctly only if there is no change

534 * from printing to dropping (or vice versa) caused by that directive.

535 * If the directive is the first of a group we have a choice between

536 * failing with an error, or passing it through unchanged instead of

537 * evaluating it. The latter is not the default to avoid questions from

538 * users about unifdef unexpectedly leaving behind preprocessor directives.

539 */

540 typedef void state_fn(void);

541

542 /* report an error */

543 static void Eelif (void) { error("Inappropriate #elif"); }

544 static void Eelse (void) { error("Inappropriate #else"); }

545 static void Eendif(void) { error("Inappropriate #endif"); }

546 static void Eeof (void) { error("Premature EOF"); }

547 static void Eioccc(void) { error("Obfuscated preprocessor control line"); }

548 /* plain line handling */

549 static void print (void) { flushline(true); }

550 static void drop (void) { flushline(false); }

551 /* output lacks group's start line */

552 static void Strue (void) { drop(); ignoreoff(); state(IS_TRUE_PREFIX); }

553 static void Sfalse(void) { drop(); ignoreoff(); state(IS_FALSE_PREFIX); }

554 static void Selse (void) { drop(); state(IS_TRUE_ELSE); }

555 /* print/pass this block */

556 static void Pelif (void) { print(); ignoreoff(); state(IS_PASS_MIDDLE); }

557 static void Pelse (void) { print(); state(IS_PASS_ELSE); }

558 static void Pendif(void) { print(); unnest(); }

559 /* discard this block */

560 static void Dfalse(void) { drop(); ignoreoff(); state(IS_FALSE_TRAILER); }

561 static void Delif (void) { drop(); ignoreoff(); state(IS_FALSE_MIDDLE); }

562 static void Delse (void) { drop(); state(IS_FALSE_ELSE); }

563 static void Dendif(void) { drop(); unnest(); }

564 /* first line of group */

565 static void Fdrop (void) { nest(); Dfalse(); }

566 static void Fpass (void) { nest(); Pelif(); }

567 static void Ftrue (void) { nest(); Strue(); }

568 static void Ffalse(void) { nest(); Sfalse(); }

569 /* variable pedantry for obfuscated lines */

570 static void Oiffy (void) { if (!iocccok) Eioccc(); Fpass(); ignoreon(); }

571 static void Oif (void) { if (!iocccok) Eioccc(); Fpass(); }

572 static void Oelif (void) { if (!iocccok) Eioccc(); Pelif(); }

573 /* ignore comments in this block */

574 static void Idrop (void) { Fdrop(); ignoreon(); }

575 static void Itrue (void) { Ftrue(); ignoreon(); }

576 static void Ifalse(void) { Ffalse(); ignoreon(); }

577 /* modify this line */

578 static void Mpass (void) { memcpy(keyword, "if ", 4); Pelif(); }

579 static void Mtrue (void) { keywordedit("else"); state(IS_TRUE_MIDDLE); }

580 static void Melif (void) { keywordedit("endif"); state(IS_FALSE_TRAILER); }

581 static void Melse (void) { keywordedit("endif"); state(IS_FALSE_ELSE); }

582

583 static state_fn * const trans_table[IS_COUNT][LT_COUNT] = {

584 /* IS_OUTSIDE */

585 { Itrue, Ifalse,Fpass, Ftrue, Ffalse,Eelif, Eelif, Eelif, Eelse, Eendif,

586 Oiffy, Oiffy, Fpass, Oif, Oif, Eelif, Eelif, Eelif, Eelse, Eendif,

587 print, done, abort },

588 /* IS_FALSE_PREFIX */

589 { Idrop, Idrop, Fdrop, Fdrop, Fdrop, Mpass, Strue, Sfalse,Selse, Dendif,

590 Idrop, Idrop, Fdrop, Fdrop, Fdrop, Mpass, Eioccc,Eioccc,Eioccc,Eioccc,

591 drop, Eeof, abort },

592 /* IS_TRUE_PREFIX */

593 { Itrue, Ifalse,Fpass, Ftrue, Ffalse,Dfalse,Dfalse,Dfalse,Delse, Dendif,

594 Oiffy, Oiffy, Fpass, Oif, Oif, Eioccc,Eioccc,Eioccc,Eioccc,Eioccc,

595 print, Eeof, abort },

596 /* IS_PASS_MIDDLE */

597 { Itrue, Ifalse,Fpass, Ftrue, Ffalse,Pelif, Mtrue, Delif, Pelse, Pendif,

598 Oiffy, Oiffy, Fpass, Oif, Oif, Pelif, Oelif, Oelif, Pelse, Pendif,

599 print, Eeof, abort },

600 /* IS_FALSE_MIDDLE */

601 { Idrop, Idrop, Fdrop, Fdrop, Fdrop, Pelif, Mtrue, Delif, Pelse, Pendif,

602 Idrop, Idrop, Fdrop, Fdrop, Fdrop, Eioccc,Eioccc,Eioccc,Eioccc,Eioccc,

603 drop, Eeof, abort },

604 /* IS_TRUE_MIDDLE */

605 { Itrue, Ifalse,Fpass, Ftrue, Ffalse,Melif, Melif, Melif, Melse, Pendif,

606 Oiffy, Oiffy, Fpass, Oif, Oif, Eioccc,Eioccc,Eioccc,Eioccc,Pendif,

607 print, Eeof, abort },

608 /* IS_PASS_ELSE */

609 { Itrue, Ifalse,Fpass, Ftrue, Ffalse,Eelif, Eelif, Eelif, Eelse, Pendif,

610 Oiffy, Oiffy, Fpass, Oif, Oif, Eelif, Eelif, Eelif, Eelse, Pendif,

611 print, Eeof, abort },

612 /* IS_FALSE_ELSE */

613 { Idrop, Idrop, Fdrop, Fdrop, Fdrop, Eelif, Eelif, Eelif, Eelse, Dendif,

614 Idrop, Idrop, Fdrop, Fdrop, Fdrop, Eelif, Eelif, Eelif, Eelse, Eioccc,

615 drop, Eeof, abort },

616 /* IS_TRUE_ELSE */

617 { Itrue, Ifalse,Fpass, Ftrue, Ffalse,Eelif, Eelif, Eelif, Eelse, Dendif,

618 Oiffy, Oiffy, Fpass, Oif, Oif, Eelif, Eelif, Eelif, Eelse, Eioccc,

619 print, Eeof, abort },

620 /* IS_FALSE_TRAILER */

621 { Idrop, Idrop, Fdrop, Fdrop, Fdrop, Dfalse,Dfalse,Dfalse,Delse, Dendif,

622 Idrop, Idrop, Fdrop, Fdrop, Fdrop, Dfalse,Dfalse,Dfalse,Delse, Eioccc,

623 drop, Eeof, abort }

624 /*TRUEI FALSEI IF TRUE FALSE ELIF ELTRUE ELFALSE ELSE ENDIF

625 TRUEI FALSEI IF TRUE FALSE ELIF ELTRUE ELFALSE ELSE ENDIF (DODGY)

626 PLAIN EOF ERROR */

627 };

628

629 /*

630 * State machine utility functions

631 */

632 static void

633 ignoreoff(void)

634 {

635 if (depth == 0)

636 abort(); /* bug */

637 ignoring[depth] = ignoring[depth-1];

638 }

639 static void

640 ignoreon(void)

641 {

642 ignoring[depth] = true;

643 }

644 static void

645 keywordedit(const char *replacement)

646 {

647 snprintf(keyword, tline + sizeof(tline) - keyword,

648 "%s%s", replacement, newline);

649 altered = true;

650 print();

651 }

652 static void

653 nest(void)

654 {

655 if (depth > MAXDEPTH-1)

656 abort(); /* bug */

657 if (depth == MAXDEPTH-1)

658 error("Too many levels of nesting");

659 depth += 1;

660 stifline[depth] = linenum;

661 }

662 static void

663 unnest(void)

664 {

665 if (depth == 0)

666 abort(); /* bug */

667 depth -= 1;

668 }

669 static void

670 state(Ifstate is)

671 {

672 ifstate[depth] = is;

673 }

674

675 /*

676 * The last state transition function. When this is called,

677 * lineval == LT_EOF, so the process() loop will terminate.

678 */

679 static void

680 done(void)

681 {

682 if (incomment)

683 error("EOF in comment");

684 closeio();

685 }

686

687 /*

688 * Write a line to the output or not, according to command line options.

689 * If writing fails, closeio() will print the error and exit.

690 */

691 static void

692 flushline(bool keep)

693 {

694 if (symlist)

695 return;

696 if (keep ^ complement) {

697 bool blankline = tline[strspn(tline, " \t\r\n")] == '\0';

698 if (blankline && compblank && blankcount != blankmax) {

699 delcount += 1;

700 blankcount += 1;

701 } else {

702 if (lnnum && delcount > 0)

703 hashline();

704 if (fputs(tline, output) == EOF)

705 closeio();

706 delcount = 0;

707 blankmax = blankcount = blankline ? blankcount + 1 : 0;

708 }

709 } else {

710 if (lnblank && fputs(newline, output) == EOF)

711 closeio();

712 altered = true;

713 delcount += 1;

714 blankcount = 0;

715 }

716 if (debugging && fflush(output) == EOF)

717 closeio();

718 }

719

720 /*

721 * Format of #line directives depends on whether we know the input filename.

722 */

723 static void

724 hashline(void)

725 {

726 int e;

727

728 if (linefile == NULL)

729 e = fprintf(output, "#line %d%s", linenum, newline);

730 else

731 e = fprintf(output, "#line %d \"%s\"%s",

732 linenum, linefile, newline);

733 if (e < 0)

734 closeio();

735 }

736

737 /*

738 * Flush the output and handle errors.

739 */

740 static void

741 closeio(void)

742 {

743 /* Tidy up after findsym(). */

744 if (symdepth && !zerosyms)

745 printf("\n");

746 if (output != NULL && (ferror(output) || fclose(output) == EOF))

747 err(2, "%s: can't write to output", filename);

748 fclose(input);

749 }

750

751 /*

752 * The driver for the state machine.

753 */

754 static void

755 process(void)

756 {

757 Linetype lineval = LT_PLAIN;

758 /* When compressing blank lines, act as if the file

759 is preceded by a large number of blank lines. */

760 blankmax = blankcount = 1000;

761 zerosyms = true;

762 newline = NULL;

763 linenum = 0;

764 altered = false;

765 while (lineval != LT_EOF) {

766 lineval = parseline();

767 trans_table[ifstate[depth]][lineval]();

768 debug("process line %d %s -> %s depth %d",

769 linenum, linetype_name[lineval],

770 ifstate_name[ifstate[depth]], depth);

771 }

772 exitstat |= altered;

773 }

774

775 /*

776 * Parse a line and determine its type. We keep the preprocessor line

777 * parser state between calls in the global variable linestate, with

778 * help from skipcomment().

779 */

780 static Linetype

781 parseline(void)

782 {

783 const char *cp;

784 int cursym;

785 Linetype retval;

786 Comment_state wascomment;

787

788 wascomment = incomment;

789 cp = skiphash();

790 if (cp == NULL)

791 return (LT_EOF);

792 if (newline == NULL) {

793 if (strrchr(tline, '\n') == strrchr(tline, '\r') + 1)

794 newline = newline_crlf;

795 else

796 newline = newline_unix;

797 }

798 if (*cp == '\0') {

799 retval = LT_PLAIN;

800 goto done;

801 }

802 keyword = tline + (cp - tline);

803 if ((cp = matchsym("ifdef", keyword)) != NULL ||

804 (cp = matchsym("ifndef", keyword)) != NULL) {

805 cp = skipcomment(cp);

806 if ((cursym = findsym(&cp)) < 0)

807 retval = LT_IF;

808 else {

809 retval = (keyword[2] == 'n')

810 ? LT_FALSE : LT_TRUE;

811 if (value[cursym] == NULL)

812 retval = (retval == LT_TRUE)

813 ? LT_FALSE : LT_TRUE;

814 if (ignore[cursym])

815 retval = (retval == LT_TRUE)

816 ? LT_TRUEI : LT_FALSEI;

817 }

818 } else if ((cp = matchsym("if", keyword)) != NULL)

819 retval = ifeval(&cp);

820 else if ((cp = matchsym("elif", keyword)) != NULL)

821 retval = linetype_if2elif(ifeval(&cp));

822 else if ((cp = matchsym("else", keyword)) != NULL)

823 retval = LT_ELSE;

824 else if ((cp = matchsym("endif", keyword)) != NULL)

825 retval = LT_ENDIF;

826 else {

827 cp = skipsym(keyword);

828 /* no way can we deal with a continuation inside a keyword */

829 if (strncmp(cp, "\\\r\n", 3) == 0 ||

830 strncmp(cp, "\\\n", 2) == 0)

831 Eioccc();

832 cp = skipline(cp);

833 retval = LT_PLAIN;

834 goto done;

835 }

836 cp = skipcomment(cp);

837 if (*cp != '\0') {

838 cp = skipline(cp);

839 if (retval == LT_TRUE || retval == LT_FALSE ||

840 retval == LT_TRUEI || retval == LT_FALSEI)

841 retval = LT_IF;

842 if (retval == LT_ELTRUE || retval == LT_ELFALSE)

843 retval = LT_ELIF;

844 }

845 /* the following can happen if the last line of the file lacks a

846 newline or if there is too much whitespace in a directive */

847 if (linestate == LS_HASH) {

848 long len = cp - tline;

849 if (fgets(tline + len, MAXLINE - len, input) == NULL) {

850 if (ferror(input))

851 err(2, "can't read %s", filename);

852 debug("parser insert newline at EOF", linenum);

853 strcpy(tline + len, newline);

854 cp += strlen(newline);

855 linestate = LS_START;

856 } else {

857 debug("parser concatenate dangling whitespace");

858 ++linenum;

859 cp = skipcomment(cp);

860 }

861 }

862 if (retval != LT_PLAIN && (wascomment || linestate != LS_START)) {

863 retval = linetype_2dodgy(retval);

864 linestate = LS_DIRTY;

865 }

866 done:

867 debug("parser line %d state %s comment %s line", linenum,

868 comment_name[incomment], linestate_name[linestate]);

869 return (retval);

870 }

871

872 /*

873 * These are the binary operators that are supported by the expression

874 * evaluator.

875 */

876 static Linetype op_strict(long *p, long v, Linetype at, Linetype bt) {

877 if(at == LT_IF || bt == LT_IF) return (LT_IF);

878 return (*p = v, v ? LT_TRUE : LT_FALSE);

879 }

880 static Linetype op_lt(long *p, Linetype at, long a, Linetype bt, long b) {

881 return op_strict(p, a < b, at, bt);

882 }

883 static Linetype op_gt(long *p, Linetype at, long a, Linetype bt, long b) {

884 return op_strict(p, a > b, at, bt);

885 }

886 static Linetype op_le(long *p, Linetype at, long a, Linetype bt, long b) {

887 return op_strict(p, a <= b, at, bt);

888 }

889 static Linetype op_ge(long *p, Linetype at, long a, Linetype bt, long b) {

890 return op_strict(p, a >= b, at, bt);

891 }

892 static Linetype op_eq(long *p, Linetype at, long a, Linetype bt, long b) {

893 return op_strict(p, a == b, at, bt);

894 }

895 static Linetype op_ne(long *p, Linetype at, long a, Linetype bt, long b) {

896 return op_strict(p, a != b, at, bt);

897 }

898 static Linetype op_or(long *p, Linetype at, long a, Linetype bt, long b) {

899 if (!strictlogic && (at == LT_TRUE || bt == LT_TRUE))

900 return (*p = 1, LT_TRUE);

901 return op_strict(p, a || b, at, bt);

902 }

903 static Linetype op_and(long *p, Linetype at, long a, Linetype bt, long b) {

904 if (!strictlogic && (at == LT_FALSE || bt == LT_FALSE))

905 return (*p = 0, LT_FALSE);

906 return op_strict(p, a && b, at, bt);

907 }

908 static Linetype op_blsh(long *p, Linetype at, long a, Linetype bt, long b) {

909 return op_strict(p, a << b, at, bt);

910 }

911 static Linetype op_brsh(long *p, Linetype at, long a, Linetype bt, long b) {

912 return op_strict(p, a >> b, at, bt);

913 }

914 static Linetype op_add(long *p, Linetype at, long a, Linetype bt, long b) {

915 return op_strict(p, a + b, at, bt);

916 }

917 static Linetype op_sub(long *p, Linetype at, long a, Linetype bt, long b) {

918 return op_strict(p, a - b, at, bt);

919 }

920 static Linetype op_mul(long *p, Linetype at, long a, Linetype bt, long b) {

921 return op_strict(p, a * b, at, bt);

922 }

923 static Linetype op_div(long *p, Linetype at, long a, Linetype bt, long b) {

924 if (bt != LT_TRUE) {

925 debug("eval division by zero");

926 return (LT_ERROR);

927 }

928 return op_strict(p, a / b, at, bt);

929 }

930 static Linetype op_mod(long *p, Linetype at, long a, Linetype bt, long b) {

931 return op_strict(p, a % b, at, bt);

932 }

933 static Linetype op_bor(long *p, Linetype at, long a, Linetype bt, long b) {

934 return op_strict(p, a | b, at, bt);

935 }

936 static Linetype op_bxor(long *p, Linetype at, long a, Linetype bt, long b) {

937 return op_strict(p, a ^ b, at, bt);

938 }

939 static Linetype op_band(long *p, Linetype at, long a, Linetype bt, long b) {

940 return op_strict(p, a & b, at, bt);

941 }

942

943 /*

944 * An evaluation function takes three arguments, as follows: (1) a pointer to

945 * an element of the precedence table which lists the operators at the current

946 * level of precedence; (2) a pointer to an integer which will receive the

947 * value of the expression; and (3) a pointer to a char* that points to the

948 * expression to be evaluated and that is updated to the end of the expression

949 * when evaluation is complete. The function returns LT_FALSE if the value of

950 * the expression is zero, LT_TRUE if it is non-zero, LT_IF if the expression

951 * depends on an unknown symbol, or LT_ERROR if there is a parse failure.

952 */

953 struct ops;

954

955 typedef Linetype eval_fn(const struct ops *, long *, const char **);

956

957 static eval_fn eval_table, eval_unary;

958

959 /*

960 * The precedence table. Expressions involving binary operators are evaluated

961 * in a table-driven way by eval_table. When it evaluates a subexpression it

962 * calls the inner function with its first argument pointing to the next

963 * element of the table. Innermost expressions have special non-table-driven

964 * handling.

965 *

966 * The stop characters help with lexical analysis: an operator is not

967 * recognized if it is followed by one of the stop characters because

968 * that would make it a different operator.

969 */

970 struct op {

971 const char *str;

972 Linetype (*fn)(long *, Linetype, long, Linetype, long);

973 const char *stop;

974 };

975 struct ops {

976 eval_fn *inner;

977 struct op op[5];

978 };

979 static const struct ops eval_ops[] = {

980 { eval_table, { { "||", op_or, NULL } } },

981 { eval_table, { { "&&", op_and, NULL } } },

982 { eval_table, { { "|", op_bor, "|" } } },

983 { eval_table, { { "^", op_bxor, NULL } } },

984 { eval_table, { { "&", op_band, "&" } } },

985 { eval_table, { { "==", op_eq, NULL },

986 { "!=", op_ne, NULL } } },

987 { eval_table, { { "<=", op_le, NULL },

988 { ">=", op_ge, NULL },

989 { "<", op_lt, "<=" },

990 { ">", op_gt, ">=" } } },

991 { eval_table, { { "<<", op_blsh, NULL },

992 { ">>", op_brsh, NULL } } },

993 { eval_table, { { "+", op_add, NULL },

994 { "-", op_sub, NULL } } },

995 { eval_unary, { { "*", op_mul, NULL },

996 { "/", op_div, NULL },

997 { "%", op_mod, NULL } } },

998 };

999

1000 /* Current operator precedence level */

1001 static long prec(const struct ops *ops)

1002 {

1003 return (ops - eval_ops);

1004 }

1005

1006 /*

1007 * Function for evaluating the innermost parts of expressions,

1008 * viz. !expr (expr) number defined(symbol) symbol

1009 * We reset the constexpr flag in the last two cases.

1010 */

1011 static Linetype

1012 eval_unary(const struct ops *ops, long *valp, const char **cpp)

1013 {

1014 const char *cp;

1015 char *ep;

1016 int sym;

1017 bool defparen;

1018 Linetype lt;

1019

1020 cp = skipcomment(*cpp);

1021 if (*cp == '!') {

1022 debug("eval%d !", prec(ops));

1023 cp++;

1024 lt = eval_unary(ops, valp, &cp);

1025 if (lt == LT_ERROR)

1026 return (LT_ERROR);

1027 if (lt != LT_IF) {

1028 *valp = !*valp;

1029 lt = *valp ? LT_TRUE : LT_FALSE;

1030 }

1031 } else if (*cp == '~') {

1032 debug("eval%d ~", prec(ops));

1033 cp++;

1034 lt = eval_unary(ops, valp, &cp);

1035 if (lt == LT_ERROR)

1036 return (LT_ERROR);

1037 if (lt != LT_IF) {

1038 *valp = ~(*valp);

1039 lt = *valp ? LT_TRUE : LT_FALSE;

1040 }

1041 } else if (*cp == '-') {

1042 debug("eval%d -", prec(ops));

1043 cp++;

1044 lt = eval_unary(ops, valp, &cp);

1045 if (lt == LT_ERROR)

1046 return (LT_ERROR);

1047 if (lt != LT_IF) {

1048 *valp = -(*valp);

1049 lt = *valp ? LT_TRUE : LT_FALSE;

1050 }

1051 } else if (*cp == '(') {

1052 cp++;

1053 debug("eval%d (", prec(ops));

1054 lt = eval_table(eval_ops, valp, &cp);

1055 if (lt == LT_ERROR)

1056 return (LT_ERROR);

1057 cp = skipcomment(cp);

1058 if (*cp++ != ')')

1059 return (LT_ERROR);

1060 } else if (isdigit((unsigned char)*cp)) {

1061 debug("eval%d number", prec(ops));

1062 *valp = strtol(cp, &ep, 0);

1063 if (ep == cp)

1064 return (LT_ERROR);

1065 lt = *valp ? LT_TRUE : LT_FALSE;

1066 cp = ep;

1067 } else if (matchsym("defined", cp) != NULL) {

1068 cp = skipcomment(cp+7);

1069 if (*cp == '(') {

1070 cp = skipcomment(cp+1);

1071 defparen = true;

1072 } else {

1073 defparen = false;

1074 }

1075 sym = findsym(&cp);

1076 cp = skipcomment(cp);

1077 if (defparen && *cp++ != ')') {

1078 debug("eval%d defined missing ')'", prec(ops));

1079 return (LT_ERROR);

1080 }

1081 if (sym < 0) {

1082 debug("eval%d defined unknown", prec(ops));

1083 lt = LT_IF;

1084 } else {

1085 debug("eval%d defined %s", prec(ops), symname[sym]);

1086 *valp = (value[sym] != NULL);

1087 lt = *valp ? LT_TRUE : LT_FALSE;

1088 }

1089 constexpr = false;

1090 } else if (!endsym(*cp)) {

1091 debug("eval%d symbol", prec(ops));

1092 sym = findsym(&cp);

1093 if (sym < 0) {

1094 lt = LT_IF;

1095 cp = skipargs(cp);

1096 } else if (value[sym] == NULL) {

1097 *valp = 0;

1098 lt = LT_FALSE;

1099 } else {

1100 *valp = strtol(value[sym], &ep, 0);

1101 if (*ep != '\0' || ep == value[sym])

1102 return (LT_ERROR);

1103 lt = *valp ? LT_TRUE : LT_FALSE;

1104 cp = skipargs(cp);

1105 }

1106 constexpr = false;

1107 } else {

1108 debug("eval%d bad expr", prec(ops));

1109 return (LT_ERROR);

1110 }

1111

1112 *cpp = cp;

1113 debug("eval%d = %d", prec(ops), *valp);

1114 return (lt);

1115 }

1116

1117 /*

1118 * Table-driven evaluation of binary operators.

1119 */

1120 static Linetype

1121 eval_table(const struct ops *ops, long *valp, const char **cpp)

1122 {

1123 const struct op *op;

1124 const char *cp;

1125 long val = 0;

1126 Linetype lt, rt;

1127

1128 debug("eval%d", prec(ops));

1129 cp = *cpp;

1130 lt = ops->inner(ops+1, valp, &cp);

1131 if (lt == LT_ERROR)

1132 return (LT_ERROR);

1133 for (;;) {

1134 cp = skipcomment(cp);

1135 for (op = ops->op; op->str != NULL; op++) {

1136 if (strncmp(cp, op->str, strlen(op->str)) == 0) {

1137 /* assume only one-char operators have stop chars */

1138 if (op->stop != NULL && cp[1] != '\0' &&

1139 strchr(op->stop, cp[1]) != NULL)

1140 continue;

1141 else

1142 break;

1143 }

1144 }

1145 if (op->str == NULL)

1146 break;

1147 cp += strlen(op->str);

1148 debug("eval%d %s", prec(ops), op->str);

1149 rt = ops->inner(ops+1, &val, &cp);

1150 if (rt == LT_ERROR)

1151 return (LT_ERROR);

1152 lt = op->fn(valp, lt, *valp, rt, val);

1153 }

1154

1155 *cpp = cp;

1156 debug("eval%d = %d", prec(ops), *valp);

1157 debug("eval%d lt = %s", prec(ops), linetype_name[lt]);

1158 return (lt);

1159 }

1160

1161 /*

1162 * Evaluate the expression on a #if or #elif line. If we can work out

1163 * the result we return LT_TRUE or LT_FALSE accordingly, otherwise we

1164 * return just a generic LT_IF.

1165 */

1166 static Linetype

1167 ifeval(const char **cpp)

1168 {

1169 Linetype ret;

1170 long val = 0;

1171

1172 debug("eval %s", *cpp);

1173 constexpr = killconsts ? false : true;

1174 ret = eval_table(eval_ops, &val, cpp);

1175 debug("eval = %d", val);

1176 return (constexpr ? LT_IF : ret == LT_ERROR ? LT_IF : ret);

1177 }

1178

1179 /*

1180 * Read a line and examine its initial part to determine if it is a

1181 * preprocessor directive. Returns NULL on EOF, or a pointer to a

1182 * preprocessor directive name, or a pointer to the zero byte at the

1183 * end of the line.

1184 */

1185 static const char *

1186 skiphash(void)

1187 {

1188 const char *cp;

1189

1190 linenum++;

1191 if (fgets(tline, MAXLINE, input) == NULL) {

1192 if (ferror(input))

1193 err(2, "can't read %s", filename);

1194 else

1195 return (NULL);

1196 }

1197 cp = skipcomment(tline);

1198 if (linestate == LS_START && *cp == '#') {

1199 linestate = LS_HASH;

1200 return (skipcomment(cp + 1));

1201 } else if (*cp == '\0') {

1202 return (cp);

1203 } else {

1204 return (skipline(cp));

1205 }

1206 }

1207

1208 /*

1209 * Mark a line dirty and consume the rest of it, keeping track of the

1210 * lexical state.

1211 */

1212 static const char *

1213 skipline(const char *cp)

1214 {

1215 const char *pcp;

1216 if (*cp != '\0')

1217 linestate = LS_DIRTY;

1218 while (*cp != '\0') {

1219 cp = skipcomment(pcp = cp);

1220 if (pcp == cp)

1221 cp++;

1222 }

1223 return (cp);

1224 }

1225

1226 /*

1227 * Skip over comments, strings, and character literals and stop at the

1228 * next character position that is not whitespace. Between calls we keep

1229 * the comment state in the global variable incomment, and we also adjust

1230 * the global variable linestate when we see a newline.

1231 * XXX: doesn't cope with the buffer splitting inside a state transition.

1232 */

1233 static const char *

1234 skipcomment(const char *cp)

1235 {

1236 if (text || ignoring[depth]) {

1237 for (; isspace((unsigned char)*cp); cp++)

1238 if (*cp == '\n')

1239 linestate = LS_START;

1240 return (cp);

1241 }

1242 while (*cp != '\0')

1243 /* don't reset to LS_START after a line continuation */

1244 if (strncmp(cp, "\\\r\n", 3) == 0)

1245 cp += 3;

1246 else if (strncmp(cp, "\\\n", 2) == 0)

1247 cp += 2;

1248 else switch (incomment) {

1249 case NO_COMMENT:

1250 if (strncmp(cp, "/\\\r\n", 4) == 0) {

1251 incomment = STARTING_COMMENT;

1252 cp += 4;

1253 } else if (strncmp(cp, "/\\\n", 3) == 0) {

1254 incomment = STARTING_COMMENT;

1255 cp += 3;

1256 } else if (strncmp(cp, "/*", 2) == 0) {

1257 incomment = C_COMMENT;

1258 cp += 2;

1259 } else if (strncmp(cp, "//", 2) == 0) {

1260 incomment = CXX_COMMENT;

1261 cp += 2;

1262 } else if (strncmp(cp, "\'", 1) == 0) {

1263 incomment = CHAR_LITERAL;

1264 linestate = LS_DIRTY;

1265 cp += 1;

1266 } else if (strncmp(cp, "\"", 1) == 0) {

1267 incomment = STRING_LITERAL;

1268 linestate = LS_DIRTY;

1269 cp += 1;

1270 } else if (strncmp(cp, "R\"(", 3) == 0) {

1271 incomment = RAW_STRING_LITERAL;

1272 linestate = LS_DIRTY;

1273 cp += 3;

1274 } else if (strncmp(cp, "\n", 1) == 0) {

1275 linestate = LS_START;

1276 cp += 1;

1277 } else if (strchr(" \r\t", *cp) != NULL) {

1278 cp += 1;

1279 } else

1280 return (cp);

1281 continue;

1282 case CXX_COMMENT:

1283 if (strncmp(cp, "\n", 1) == 0) {

1284 incomment = NO_COMMENT;

1285 linestate = LS_START;

1286 }

1287 cp += 1;

1288 continue;

1289 case CHAR_LITERAL:

1290 case STRING_LITERAL:

1291 if ((incomment == CHAR_LITERAL && cp[0] == '\'') ||

1292 (incomment == STRING_LITERAL && cp[0] == '\"')) {

1293 incomment = NO_COMMENT;

1294 cp += 1;

1295 } else if (cp[0] == '\\') {

1296 if (cp[1] == '\0')

1297 cp += 1;

1298 else

1299 cp += 2;

1300 } else if (strncmp(cp, "\n", 1) == 0) {

1301 if (incomment == CHAR_LITERAL)

1302 error("Unterminated char literal");

1303 else

1304 error("Unterminated string literal");

1305 } else

1306 cp += 1;

1307 continue;

1308 case RAW_STRING_LITERAL:

1309 if (strncmp(cp, ")\"", 2) == 0) {

1310 incomment = NO_COMMENT;

1311 cp += 2;

1312 } else

1313 cp += 1;

1314 continue;

1315 case C_COMMENT:

1316 if (strncmp(cp, "*\\\r\n", 4) == 0) {

1317 incomment = FINISHING_COMMENT;

1318 cp += 4;

1319 } else if (strncmp(cp, "*\\\n", 3) == 0) {

1320 incomment = FINISHING_COMMENT;

1321 cp += 3;

1322 } else if (strncmp(cp, "*/", 2) == 0) {

1323 incomment = NO_COMMENT;

1324 cp += 2;

1325 } else

1326 cp += 1;

1327 continue;

1328 case STARTING_COMMENT:

1329 if (*cp == '*') {

1330 incomment = C_COMMENT;

1331 cp += 1;

1332 } else if (*cp == '/') {

1333 incomment = CXX_COMMENT;

1334 cp += 1;

1335 } else {

1336 incomment = NO_COMMENT;

1337 linestate = LS_DIRTY;

1338 }

1339 continue;

1340 case FINISHING_COMMENT:

1341 if (*cp == '/') {

1342 incomment = NO_COMMENT;

1343 cp += 1;

1344 } else

1345 incomment = C_COMMENT;

1346 continue;

1347 default:

1348 abort(); /* bug */

1349 }

1350 return (cp);

1351 }

1352

1353 /*

1354 * Skip macro arguments.

1355 */

1356 static const char *

1357 skipargs(const char *cp)

1358 {

1359 const char *ocp = cp;

1360 int level = 0;

1361 cp = skipcomment(cp);

1362 if (*cp != '(')

1363 return (cp);

1364 do {

1365 if (*cp == '(')

1366 level++;

1367 if (*cp == ')')

1368 level--;

1369 cp = skipcomment(cp+1);

1370 } while (level != 0 && *cp != '\0');

1371 if (level == 0)

1372 return (cp);

1373 else

1374 /* Rewind and re-detect the syntax error later. */

1375 return (ocp);

1376 }

1377

1378 /*

1379 * Skip over an identifier.

1380 */

1381 static const char *

1382 skipsym(const char *cp)

1383 {

1384 while (!endsym(*cp))

1385 ++cp;

1386 return (cp);

1387 }

1388

1389 /*

1390 * Skip whitespace and take a copy of any following identifier.

1391 */

1392 static const char *

1393 getsym(const char **cpp)

1394 {

1395 const char *cp = *cpp, *sym;

1396

1397 cp = skipcomment(cp);

1398 cp = skipsym(sym = cp);

1399 if (cp == sym)

1400 return NULL;

1401 *cpp = cp;

1402 return (xstrdup(sym, cp));

1403 }

1404

1405 /*

1406 * Check that s (a symbol) matches the start of t, and that the

1407 * following character in t is not a symbol character. Returns a

1408 * pointer to the following character in t if there is a match,

1409 * otherwise NULL.

1410 */

1411 static const char *

1412 matchsym(const char *s, const char *t)

1413 {

1414 while (*s != '\0' && *t != '\0')

1415 if (*s != *t)

1416 return (NULL);

1417 else

1418 ++s, ++t;

1419 if (*s == '\0' && endsym(*t))

1420 return(t);

1421 else

1422 return(NULL);

1423 }

1424

1425 /*

1426 * Look for the symbol in the symbol table. If it is found, we return

1427 * the symbol table index, else we return -1.

1428 */

1429 static int

1430 findsym(const char **strp)

1431 {

1432 const char *str;

1433 int symind;

1434

1435 str = *strp;

1436 *strp = skipsym(str);

1437 if (symlist) {

1438 if (*strp == str)

1439 return (-1);

1440 if (symdepth && firstsym)

1441 printf("%s%3d", zerosyms ? "" : "\n", depth);

1442 firstsym = zerosyms = false;

1443 printf("%s%.*s%s",

1444 symdepth ? " " : "",

1445 (int)(*strp-str), str,

1446 symdepth ? "" : "\n");

1447 /* we don't care about the value of the symbol */

1448 return (0);

1449 }

1450 for (symind = 0; symind < nsyms; ++symind) {

1451 if (matchsym(symname[symind], str) != NULL) {

1452 debugsym("findsym", symind);

1453 return (symind);

1454 }

1455 }

1456 return (-1);

1457 }

1458

1459 /*

1460 * Resolve indirect symbol values to their final definitions.

1461 */

1462 static void

1463 indirectsym(void)

1464 {

1465 const char *cp;

1466 int changed, sym, ind;

1467

1468 do {

1469 changed = 0;

1470 for (sym = 0; sym < nsyms; ++sym) {

1471 if (value[sym] == NULL)

1472 continue;

1473 cp = value[sym];

1474 ind = findsym(&cp);

1475 if (ind == -1 || ind == sym ||

1476 *cp != '\0' ||

1477 value[ind] == NULL ||

1478 value[ind] == value[sym])

1479 continue;

1480 debugsym("indir...", sym);

1481 value[sym] = value[ind];

1482 debugsym("...ectsym", sym);

1483 changed++;

1484 }

1485 } while (changed);

1486 }

1487

1488 /*

1489 * Add a symbol to the symbol table, specified with the format sym=val

1490 */

1491 static void

1492 addsym1(bool ignorethis, bool definethis, char *symval)

1493 {

1494 const char *sym, *val;

1495

1496 sym = symval;

1497 val = skipsym(sym);

1498 if (definethis && *val == '=') {

1499 symval[val - sym] = '\0';

1500 val = val + 1;

1501 } else if (*val == '\0') {

1502 val = definethis ? "1" : NULL;

1503 } else {

1504 usage();

1505 }

1506 addsym2(ignorethis, sym, val);

1507 }

1508

1509 /*

1510 * Add a symbol to the symbol table.

1511 */

1512 static void

1513 addsym2(bool ignorethis, const char *sym, const char *val)

1514 {

1515 const char *cp = sym;

1516 int symind;

1517

1518 symind = findsym(&cp);

1519 if (symind < 0) {

1520 if (nsyms >= MAXSYMS)

1521 errx(2, "too many symbols");

1522 symind = nsyms++;

1523 }

1524 ignore[symind] = ignorethis;

1525 symname[symind] = sym;

1526 value[symind] = val;

1527 debugsym("addsym", symind);

1528 }

1529

1530 static void

1531 debugsym(const char *why, int symind)

1532 {

1533 debug("%s %s%c%s", why, symname[symind],

1534 value[symind] ? '=' : ' ',

1535 value[symind] ? value[symind] : "undef");

1536 }

1537

1538 /*

1539 * Add symbols to the symbol table from a file containing

1540 * #define and #undef preprocessor directives.

1541 */

1542 static void

1543 defundefile(const char *fn)

1544 {

1545 filename = fn;

1546 input = fopen(fn, "rb");

1547 if (input == NULL)

1548 err(2, "can't open %s", fn);

1549 linenum = 0;

1550 while (defundef())

1551 ;

1552 if (ferror(input))

1553 err(2, "can't read %s", filename);

1554 else

1555 fclose(input);

1556 if (incomment)

1557 error("EOF in comment");

1558 }

1559

1560 /*

1561 * Read and process one #define or #undef directive

1562 */

1563 static bool

1564 defundef(void)

1565 {

1566 const char *cp, *kw, *sym, *val, *end;

1567

1568 cp = skiphash();

1569 if (cp == NULL)

1570 return (false);

1571 if (*cp == '\0')

1572 goto done;

1573 /* strip trailing whitespace, and do a fairly rough check to

1574 avoid unsupported multi-line preprocessor directives */

1575 end = cp + strlen(cp);

1576 while (end > tline && strchr(" \t\n\r", end[-1]) != NULL)

1577 --end;

1578 if (end > tline && end[-1] == '\\')

1579 Eioccc();

1580

1581 kw = cp;

1582 if ((cp = matchsym("define", kw)) != NULL) {

1583 sym = getsym(&cp);

1584 if (sym == NULL)

1585 error("Missing macro name in #define");

1586 if (*cp == '(') {

1587 val = "1";

1588 } else {

1589 cp = skipcomment(cp);

1590 val = (cp < end) ? xstrdup(cp, end) : "";

1591 }

1592 debug("#define");

1593 addsym2(false, sym, val);

1594 } else if ((cp = matchsym("undef", kw)) != NULL) {

1595 sym = getsym(&cp);

1596 if (sym == NULL)

1597 error("Missing macro name in #undef");

1598 cp = skipcomment(cp);

1599 debug("#undef");

1600 addsym2(false, sym, NULL);

1601 } else {

1602 error("Unrecognized preprocessor directive");

1603 }

1604 skipline(cp);

1605 done:

1606 debug("parser line %d state %s comment %s line", linenum,

1607 comment_name[incomment], linestate_name[linestate]);

1608 return (true);

1609 }

1610

1611 /*

1612 * Concatenate two strings into new memory, checking for failure.

1613 */

1614 static char *

1615 astrcat(const char *s1, const char *s2)

1616 {

1617 char *s;

1618 int len;

1619 size_t size;

1620

1621 len = snprintf(NULL, 0, "%s%s", s1, s2);

1622 if (len < 0)

1623 err(2, "snprintf");

1624 size = (size_t)len + 1;

1625 s = (char *)malloc(size);

1626 if (s == NULL)

1627 err(2, "malloc");

1628 snprintf(s, size, "%s%s", s1, s2);

1629 return (s);

1630 }

1631

1632 /*

1633 * Duplicate a segment of a string, checking for failure.

1634 */

1635 static const char *

1636 xstrdup(const char *start, const char *end)

1637 {

1638 size_t n;

1639 char *s;

1640

1641 if (end < start) abort(); /* bug */

1642 n = (size_t)(end - start) + 1;

1643 s = (char *)malloc(n);

1644 if (s == NULL)

1645 err(2, "malloc");

1646 snprintf(s, n, "%s", start);

1647 return (s);

1648 }

1649

1650 /*

1651 * Diagnostics.

1652 */

1653 static void

1654 debug(const char *msg, ...)

1655 {

1656 va_list ap;

1657

1658 if (debugging) {

1659 va_start(ap, msg);

1660 vwarnx(msg, ap);

1661 va_end(ap);

1662 }

1663 }

1664

1665 static void

1666 error(const char *msg)

1667 {

1668 if (depth == 0)

1669 warnx("%s: %d: %s", filename, linenum, msg);

1670 else

1671 warnx("%s: %d: %s (#if line %d depth %d)",

1672 filename, linenum, msg, stifline[depth], depth);

1673 closeio();

1674 errx(2, "Output may be truncated");

1675 }