1 /* 2 * Copyright (c) 2002 - 2014 Tony Finch <dot@dotat.at> 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: jmc $\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 } Comment_state; 119 120 static char const * const comment_name[] = { 121 "NO", "C", "CXX", "STARTING", "FINISHING", "CHAR", "STRING" 122 }; 123 124 /* state of preprocessor line parser */ 125 typedef enum { 126 LS_START, /* only space and comments on this line */ 127 LS_HASH, /* only space, comments, and a hash */ 128 LS_DIRTY /* this line can't be a preprocessor line */ 129 } Line_state; 130 131 static char const * const linestate_name[] = { 132 "START", "HASH", "DIRTY" 133 }; 134 135 /* 136 * Minimum translation limits from ISO/IEC 9899:1999 5.2.4.1 137 */ 138 #define MAXDEPTH 64 /* maximum #if nesting */ 139 #define MAXLINE 4096 /* maximum length of line */ 140 #define MAXSYMS 16384 /* maximum number of symbols */ 141 142 /* 143 * Sometimes when editing a keyword the replacement text is longer, so 144 * we leave some space at the end of the tline buffer to accommodate this. 145 */ 146 #define EDITSLOP 10 147 148 /* 149 * Globals. 150 */ 151 152 static bool compblank; /* -B: compress blank lines */ 153 static bool lnblank; /* -b: blank deleted lines */ 154 static bool complement; /* -c: do the complement */ 155 static bool debugging; /* -d: debugging reports */ 156 static bool inplace; /* -m: modify in place */ 157 static bool iocccok; /* -e: fewer IOCCC errors */ 158 static bool strictlogic; /* -K: keep ambiguous #ifs */ 159 static bool killconsts; /* -k: eval constant #ifs */ 160 static bool lnnum; /* -n: add #line directives */ 161 static bool symlist; /* -s: output symbol list */ 162 static bool symdepth; /* -S: output symbol depth */ 163 static bool text; /* -t: this is a text file */ 164 165 static const char *symname[MAXSYMS]; /* symbol name */ 166 static const char *value[MAXSYMS]; /* -Dsym=value */ 167 static bool ignore[MAXSYMS]; /* -iDsym or -iUsym */ 168 static int nsyms; /* number of symbols */ 169 170 static FILE *input; /* input file pointer */ 171 static const char *filename; /* input file name */ 172 static int linenum; /* current line number */ 173 static const char *linefile; /* file name for #line */ 174 static FILE *output; /* output file pointer */ 175 static const char *ofilename; /* output file name */ 176 static const char *backext; /* backup extension */ 177 static char *tempname; /* avoid splatting input */ 178 179 static char tline[MAXLINE+EDITSLOP];/* input buffer plus space */ 180 static char *keyword; /* used for editing #elif's */ 181 182 /* 183 * When processing a file, the output's newline style will match the 184 * input's, and unifdef correctly handles CRLF or LF endings whatever 185 * the platform's native style. The stdio streams are opened in binary 186 * mode to accommodate platforms whose native newline style is CRLF. 187 * When the output isn't a processed input file (when it is error / 188 * debug / diagnostic messages) then unifdef uses native line endings. 189 */ 190 191 static const char *newline; /* input file format */ 192 static const char newline_unix[] = "\n"; 193 static const char newline_crlf[] = "\r\n"; 194 195 static Comment_state incomment; /* comment parser state */ 196 static Line_state linestate; /* #if line parser state */ 197 static Ifstate ifstate[MAXDEPTH]; /* #if processor state */ 198 static bool ignoring[MAXDEPTH]; /* ignore comments state */ 199 static int stifline[MAXDEPTH]; /* start of current #if */ 200 static int depth; /* current #if nesting */ 201 static int delcount; /* count of deleted lines */ 202 static unsigned blankcount; /* count of blank lines */ 203 static unsigned blankmax; /* maximum recent blankcount */ 204 static bool constexpr; /* constant #if expression */ 205 static bool zerosyms; /* to format symdepth output */ 206 static bool firstsym; /* ditto */ 207 208 static int exitmode; /* exit status mode */ 209 static int exitstat; /* program exit status */ 210 211 static void addsym1(bool, bool, char *); 212 static void addsym2(bool, const char *, const char *); 213 static char *astrcat(const char *, const char *); 214 static void cleantemp(void); 215 static void closeio(void); 216 static void debug(const char *, ...); 217 static void debugsym(const char *, int); 218 static bool defundef(void); 219 static void defundefile(const char *); 220 static void done(void); 221 static void error(const char *); 222 static int findsym(const char **); 223 static void flushline(bool); 224 static void hashline(void); 225 static void help(void); 226 static Linetype ifeval(const char **); 227 static void ignoreoff(void); 228 static void ignoreon(void); 229 static void indirectsym(void); 230 static void keywordedit(const char *); 231 static const char *matchsym(const char *, const char *); 232 static void nest(void); 233 static Linetype parseline(void); 234 static void process(void); 235 static void processinout(const char *, const char *); 236 static const char *skipargs(const char *); 237 static const char *skipcomment(const char *); 238 static const char *skiphash(void); 239 static const char *skipline(const char *); 240 static const char *skipsym(const char *); 241 static void state(Ifstate); 242 static void unnest(void); 243 static void usage(void); 244 static void version(void); 245 static const char *xstrdup(const char *, const char *); 246 247 #define endsym(c) (!isalnum((unsigned char)c) && c != '_') 248 249 /* 250 * The main program. 251 */ 252 int 253 main(int argc, char *argv[]) 254 { 255 int opt; 256 257 while ((opt = getopt(argc, argv, "i:D:U:f:I:M:o:x:bBcdehKklmnsStV")) != -1) 258 switch (opt) { 259 case 'i': /* treat stuff controlled by these symbols as text */ 260 /* 261 * For strict backwards-compatibility the U or D 262 * should be immediately after the -i but it doesn't 263 * matter much if we relax that requirement. 264 */ 265 opt = *optarg++; 266 if (opt == 'D') 267 addsym1(true, true, optarg); 268 else if (opt == 'U') 269 addsym1(true, false, optarg); 270 else 271 usage(); 272 break; 273 case 'D': /* define a symbol */ 274 addsym1(false, true, optarg); 275 break; 276 case 'U': /* undef a symbol */ 277 addsym1(false, false, optarg); 278 break; 279 case 'I': /* no-op for compatibility with cpp */ 280 break; 281 case 'b': /* blank deleted lines instead of omitting them */ 282 case 'l': /* backwards compatibility */ 283 lnblank = true; 284 break; 285 case 'B': /* compress blank lines around removed section */ 286 compblank = true; 287 break; 288 case 'c': /* treat -D as -U and vice versa */ 289 complement = true; 290 break; 291 case 'd': 292 debugging = true; 293 break; 294 case 'e': /* fewer errors from dodgy lines */ 295 iocccok = true; 296 break; 297 case 'f': /* definitions file */ 298 defundefile(optarg); 299 break; 300 case 'h': 301 help(); 302 break; 303 case 'K': /* keep ambiguous #ifs */ 304 strictlogic = true; 305 break; 306 case 'k': /* process constant #ifs */ 307 killconsts = true; 308 break; 309 case 'm': /* modify in place */ 310 inplace = true; 311 break; 312 case 'M': /* modify in place and keep backup */ 313 inplace = true; 314 backext = optarg; 315 break; 316 case 'n': /* add #line directive after deleted lines */ 317 lnnum = true; 318 break; 319 case 'o': /* output to a file */ 320 ofilename = optarg; 321 break; 322 case 's': /* only output list of symbols that control #ifs */ 323 symlist = true; 324 break; 325 case 'S': /* list symbols with their nesting depth */ 326 symlist = symdepth = true; 327 break; 328 case 't': /* don't parse C comments */ 329 text = true; 330 break; 331 case 'V': 332 version(); 333 break; 334 case 'x': 335 exitmode = atoi(optarg); 336 if(exitmode < 0 || exitmode > 2) 337 usage(); 338 break; 339 default: 340 usage(); 341 } 342 argc -= optind; 343 argv += optind; 344 if (compblank && lnblank) 345 errx(2, "-B and -b are mutually exclusive"); 346 if (symlist && (ofilename != NULL || inplace || argc > 1)) 347 errx(2, "-s only works with one input file"); 348 if (argc > 1 && ofilename != NULL) 349 errx(2, "-o cannot be used with multiple input files"); 350 if (argc > 1 && !inplace) 351 errx(2, "multiple input files require -m or -M"); 352 if (argc == 0) 353 argc = 1; 354 if (argc == 1 && !inplace && ofilename == NULL) 355 ofilename = "-"; 356 indirectsym(); 357 358 atexit(cleantemp); 359 if (ofilename != NULL) 360 processinout(*argv, ofilename); 361 else while (argc-- > 0) { 362 processinout(*argv, *argv); 363 argv++; 364 } 365 switch(exitmode) { 366 case(0): exit(exitstat); 367 case(1): exit(!exitstat); 368 case(2): exit(0); 369 default: abort(); /* bug */ 370 } 371 } 372 373 /* 374 * File logistics. 375 */ 376 static void 377 processinout(const char *ifn, const char *ofn) 378 { 379 struct stat st; 380 381 if (ifn == NULL || strcmp(ifn, "-") == 0) { 382 filename = "[stdin]"; 383 linefile = NULL; 384 input = fbinmode(stdin); 385 } else { 386 filename = ifn; 387 linefile = ifn; 388 input = fopen(ifn, "rb"); 389 if (input == NULL) 390 err(2, "can't open %s", ifn); 391 } 392 if (strcmp(ofn, "-") == 0) { 393 output = fbinmode(stdout); 394 process(); 395 return; 396 } 397 if (stat(ofn, &st) < 0) { 398 output = fopen(ofn, "wb"); 399 if (output == NULL) 400 err(2, "can't create %s", ofn); 401 process(); 402 return; 403 } 404 405 tempname = astrcat(ofn, ".XXXXXX"); 406 output = mktempmode(tempname, st.st_mode); 407 if (output == NULL) 408 err(2, "can't create %s", tempname); 409 410 process(); 411 412 if (backext != NULL) { 413 char *backname = astrcat(ofn, backext); 414 if (rename(ofn, backname) < 0) 415 err(2, "can't rename \"%s\" to \"%s\"", ofn, backname); 416 free(backname); 417 } 418 if (replace(tempname, ofn) < 0) 419 err(2, "can't rename \"%s\" to \"%s\"", tempname, ofn); 420 free(tempname); 421 tempname = NULL; 422 } 423 424 /* 425 * For cleaning up if there is an error. 426 */ 427 static void 428 cleantemp(void) 429 { 430 if (tempname != NULL) 431 remove(tempname); 432 } 433 434 /* 435 * Self-identification functions. 436 */ 437 438 static void 439 version(void) 440 { 441 const char *c = copyright; 442 for (;;) { 443 while (*++c != '$') 444 if (*c == '\0') 445 exit(0); 446 while (*++c != '$') 447 putc(*c, stderr); 448 putc('\n', stderr); 449 } 450 } 451 452 static void 453 synopsis(FILE *fp) 454 { 455 fprintf(fp, 456 "usage: unifdef [-BbcdehKkmnSstV] [-[i]Dsym[=val]] [-[i]Usym] [-f defile]\n" 457 " [-M backext] [-o outfile] [-x 0 | 1 | 2] file ...\n"); 458 } 459 460 static void 461 usage(void) 462 { 463 synopsis(stderr); 464 exit(2); 465 } 466 467 static void 468 help(void) 469 { 470 synopsis(stdout); 471 printf( 472 " -Dsym=val define preprocessor symbol with given value\n" 473 " -Dsym define preprocessor symbol with value 1\n" 474 " -Usym preprocessor symbol is undefined\n" 475 " -iDsym=val \\ ignore C strings and comments\n" 476 " -iDsym ) in sections controlled by these\n" 477 " -iUsym / preprocessor symbols\n" 478 " -fpath file containing #define and #undef directives\n" 479 " -b blank lines instead of deleting them\n" 480 " -B compress blank lines around deleted section\n" 481 " -c complement (invert) keep vs. delete\n" 482 " -d debugging mode\n" 483 " -e ignore multiline preprocessor directives\n" 484 " -h print help\n" 485 " -Ipath extra include file path (ignored)\n" 486 " -K disable && and || short-circuiting\n" 487 " -k process constant #if expressions\n" 488 " -Mext modify in place and keep backups\n" 489 " -m modify input files in place\n" 490 " -n add #line directives to output\n" 491 " -opath output file name\n" 492 " -S list #if control symbols with nesting\n" 493 " -s list #if control symbols\n" 494 " -t ignore C strings and comments\n" 495 " -V print version\n" 496 " -x{012} exit status mode\n" 497 ); 498 exit(0); 499 } 500 501 /* 502 * A state transition function alters the global #if processing state 503 * in a particular way. The table below is indexed by the current 504 * processing state and the type of the current line. 505 * 506 * Nesting is handled by keeping a stack of states; some transition 507 * functions increase or decrease the depth. They also maintain the 508 * ignore state on a stack. In some complicated cases they have to 509 * alter the preprocessor directive, as follows. 510 * 511 * When we have processed a group that starts off with a known-false 512 * #if/#elif sequence (which has therefore been deleted) followed by a 513 * #elif that we don't understand and therefore must keep, we edit the 514 * latter into a #if to keep the nesting correct. We use memcpy() to 515 * overwrite the 4 byte token "elif" with "if " without a '\0' byte. 516 * 517 * When we find a true #elif in a group, the following block will 518 * always be kept and the rest of the sequence after the next #elif or 519 * #else will be discarded. We edit the #elif into a #else and the 520 * following directive to #endif since this has the desired behaviour. 521 * 522 * "Dodgy" directives are split across multiple lines, the most common 523 * example being a multi-line comment hanging off the right of the 524 * directive. We can handle them correctly only if there is no change 525 * from printing to dropping (or vice versa) caused by that directive. 526 * If the directive is the first of a group we have a choice between 527 * failing with an error, or passing it through unchanged instead of 528 * evaluating it. The latter is not the default to avoid questions from 529 * users about unifdef unexpectedly leaving behind preprocessor directives. 530 */ 531 typedef void state_fn(void); 532 533 /* report an error */ 534 static void Eelif (void) { error("Inappropriate #elif"); } 535 static void Eelse (void) { error("Inappropriate #else"); } 536 static void Eendif(void) { error("Inappropriate #endif"); } 537 static void Eeof (void) { error("Premature EOF"); } 538 static void Eioccc(void) { error("Obfuscated preprocessor control line"); } 539 /* plain line handling */ 540 static void print (void) { flushline(true); } 541 static void drop (void) { flushline(false); } 542 /* output lacks group's start line */ 543 static void Strue (void) { drop(); ignoreoff(); state(IS_TRUE_PREFIX); } 544 static void Sfalse(void) { drop(); ignoreoff(); state(IS_FALSE_PREFIX); } 545 static void Selse (void) { drop(); state(IS_TRUE_ELSE); } 546 /* print/pass this block */ 547 static void Pelif (void) { print(); ignoreoff(); state(IS_PASS_MIDDLE); } 548 static void Pelse (void) { print(); state(IS_PASS_ELSE); } 549 static void Pendif(void) { print(); unnest(); } 550 /* discard this block */ 551 static void Dfalse(void) { drop(); ignoreoff(); state(IS_FALSE_TRAILER); } 552 static void Delif (void) { drop(); ignoreoff(); state(IS_FALSE_MIDDLE); } 553 static void Delse (void) { drop(); state(IS_FALSE_ELSE); } 554 static void Dendif(void) { drop(); unnest(); } 555 /* first line of group */ 556 static void Fdrop (void) { nest(); Dfalse(); } 557 static void Fpass (void) { nest(); Pelif(); } 558 static void Ftrue (void) { nest(); Strue(); } 559 static void Ffalse(void) { nest(); Sfalse(); } 560 /* variable pedantry for obfuscated lines */ 561 static void Oiffy (void) { if (!iocccok) Eioccc(); Fpass(); ignoreon(); } 562 static void Oif (void) { if (!iocccok) Eioccc(); Fpass(); } 563 static void Oelif (void) { if (!iocccok) Eioccc(); Pelif(); } 564 /* ignore comments in this block */ 565 static void Idrop (void) { Fdrop(); ignoreon(); } 566 static void Itrue (void) { Ftrue(); ignoreon(); } 567 static void Ifalse(void) { Ffalse(); ignoreon(); } 568 /* modify this line */ 569 static void Mpass (void) { memcpy(keyword, "if ", 4); Pelif(); } 570 static void Mtrue (void) { keywordedit("else"); state(IS_TRUE_MIDDLE); } 571 static void Melif (void) { keywordedit("endif"); state(IS_FALSE_TRAILER); } 572 static void Melse (void) { keywordedit("endif"); state(IS_FALSE_ELSE); } 573 574 static state_fn * const trans_table[IS_COUNT][LT_COUNT] = { 575 /* IS_OUTSIDE */ 576 { Itrue, Ifalse,Fpass, Ftrue, Ffalse,Eelif, Eelif, Eelif, Eelse, Eendif, 577 Oiffy, Oiffy, Fpass, Oif, Oif, Eelif, Eelif, Eelif, Eelse, Eendif, 578 print, done, abort }, 579 /* IS_FALSE_PREFIX */ 580 { Idrop, Idrop, Fdrop, Fdrop, Fdrop, Mpass, Strue, Sfalse,Selse, Dendif, 581 Idrop, Idrop, Fdrop, Fdrop, Fdrop, Mpass, Eioccc,Eioccc,Eioccc,Eioccc, 582 drop, Eeof, abort }, 583 /* IS_TRUE_PREFIX */ 584 { Itrue, Ifalse,Fpass, Ftrue, Ffalse,Dfalse,Dfalse,Dfalse,Delse, Dendif, 585 Oiffy, Oiffy, Fpass, Oif, Oif, Eioccc,Eioccc,Eioccc,Eioccc,Eioccc, 586 print, Eeof, abort }, 587 /* IS_PASS_MIDDLE */ 588 { Itrue, Ifalse,Fpass, Ftrue, Ffalse,Pelif, Mtrue, Delif, Pelse, Pendif, 589 Oiffy, Oiffy, Fpass, Oif, Oif, Pelif, Oelif, Oelif, Pelse, Pendif, 590 print, Eeof, abort }, 591 /* IS_FALSE_MIDDLE */ 592 { Idrop, Idrop, Fdrop, Fdrop, Fdrop, Pelif, Mtrue, Delif, Pelse, Pendif, 593 Idrop, Idrop, Fdrop, Fdrop, Fdrop, Eioccc,Eioccc,Eioccc,Eioccc,Eioccc, 594 drop, Eeof, abort }, 595 /* IS_TRUE_MIDDLE */ 596 { Itrue, Ifalse,Fpass, Ftrue, Ffalse,Melif, Melif, Melif, Melse, Pendif, 597 Oiffy, Oiffy, Fpass, Oif, Oif, Eioccc,Eioccc,Eioccc,Eioccc,Pendif, 598 print, Eeof, abort }, 599 /* IS_PASS_ELSE */ 600 { Itrue, Ifalse,Fpass, Ftrue, Ffalse,Eelif, Eelif, Eelif, Eelse, Pendif, 601 Oiffy, Oiffy, Fpass, Oif, Oif, Eelif, Eelif, Eelif, Eelse, Pendif, 602 print, Eeof, abort }, 603 /* IS_FALSE_ELSE */ 604 { Idrop, Idrop, Fdrop, Fdrop, Fdrop, Eelif, Eelif, Eelif, Eelse, Dendif, 605 Idrop, Idrop, Fdrop, Fdrop, Fdrop, Eelif, Eelif, Eelif, Eelse, Eioccc, 606 drop, Eeof, abort }, 607 /* IS_TRUE_ELSE */ 608 { Itrue, Ifalse,Fpass, Ftrue, Ffalse,Eelif, Eelif, Eelif, Eelse, Dendif, 609 Oiffy, Oiffy, Fpass, Oif, Oif, Eelif, Eelif, Eelif, Eelse, Eioccc, 610 print, Eeof, abort }, 611 /* IS_FALSE_TRAILER */ 612 { Idrop, Idrop, Fdrop, Fdrop, Fdrop, Dfalse,Dfalse,Dfalse,Delse, Dendif, 613 Idrop, Idrop, Fdrop, Fdrop, Fdrop, Dfalse,Dfalse,Dfalse,Delse, Eioccc, 614 drop, Eeof, abort } 615 /*TRUEI FALSEI IF TRUE FALSE ELIF ELTRUE ELFALSE ELSE ENDIF 616 TRUEI FALSEI IF TRUE FALSE ELIF ELTRUE ELFALSE ELSE ENDIF (DODGY) 617 PLAIN EOF ERROR */ 618 }; 619 620 /* 621 * State machine utility functions 622 */ 623 static void 624 ignoreoff(void) 625 { 626 if (depth == 0) 627 abort(); /* bug */ 628 ignoring[depth] = ignoring[depth-1]; 629 } 630 static void 631 ignoreon(void) 632 { 633 ignoring[depth] = true; 634 } 635 static void 636 keywordedit(const char *replacement) 637 { 638 snprintf(keyword, tline + sizeof(tline) - keyword, 639 "%s%s", replacement, newline); 640 print(); 641 } 642 static void 643 nest(void) 644 { 645 if (depth > MAXDEPTH-1) 646 abort(); /* bug */ 647 if (depth == MAXDEPTH-1) 648 error("Too many levels of nesting"); 649 depth += 1; 650 stifline[depth] = linenum; 651 } 652 static void 653 unnest(void) 654 { 655 if (depth == 0) 656 abort(); /* bug */ 657 depth -= 1; 658 } 659 static void 660 state(Ifstate is) 661 { 662 ifstate[depth] = is; 663 } 664 665 /* 666 * The last state transition function. When this is called, 667 * lineval == LT_EOF, so the process() loop will terminate. 668 */ 669 static void 670 done(void) 671 { 672 if (incomment) 673 error("EOF in comment"); 674 closeio(); 675 } 676 677 /* 678 * Write a line to the output or not, according to command line options. 679 * If writing fails, closeio() will print the error and exit. 680 */ 681 static void 682 flushline(bool keep) 683 { 684 if (symlist) 685 return; 686 if (keep ^ complement) { 687 bool blankline = tline[strspn(tline, " \t\r\n")] == '\0'; 688 if (blankline && compblank && blankcount != blankmax) { 689 delcount += 1; 690 blankcount += 1; 691 } else { 692 if (lnnum && delcount > 0) 693 hashline(); 694 if (fputs(tline, output) == EOF) 695 closeio(); 696 delcount = 0; 697 blankmax = blankcount = blankline ? blankcount + 1 : 0; 698 } 699 } else { 700 if (lnblank && fputs(newline, output) == EOF) 701 closeio(); 702 exitstat = 1; 703 delcount += 1; 704 blankcount = 0; 705 } 706 if (debugging && fflush(output) == EOF) 707 closeio(); 708 } 709 710 /* 711 * Format of #line directives depends on whether we know the input filename. 712 */ 713 static void 714 hashline(void) 715 { 716 int e; 717 718 if (linefile == NULL) 719 e = fprintf(output, "#line %d%s", linenum, newline); 720 else 721 e = fprintf(output, "#line %d \"%s\"%s", 722 linenum, linefile, newline); 723 if (e < 0) 724 closeio(); 725 } 726 727 /* 728 * Flush the output and handle errors. 729 */ 730 static void 731 closeio(void) 732 { 733 /* Tidy up after findsym(). */ 734 if (symdepth && !zerosyms) 735 printf("\n"); 736 if (output != NULL && (ferror(output) || fclose(output) == EOF)) 737 err(2, "%s: can't write to output", filename); 738 fclose(input); 739 } 740 741 /* 742 * The driver for the state machine. 743 */ 744 static void 745 process(void) 746 { 747 Linetype lineval = LT_PLAIN; 748 /* When compressing blank lines, act as if the file 749 is preceded by a large number of blank lines. */ 750 blankmax = blankcount = 1000; 751 zerosyms = true; 752 newline = NULL; 753 linenum = 0; 754 while (lineval != LT_EOF) { 755 lineval = parseline(); 756 trans_table[ifstate[depth]][lineval](); 757 debug("process line %d %s -> %s depth %d", 758 linenum, linetype_name[lineval], 759 ifstate_name[ifstate[depth]], depth); 760 } 761 } 762 763 /* 764 * Parse a line and determine its type. We keep the preprocessor line 765 * parser state between calls in the global variable linestate, with 766 * help from skipcomment(). 767 */ 768 static Linetype 769 parseline(void) 770 { 771 const char *cp; 772 int cursym; 773 Linetype retval; 774 Comment_state wascomment; 775 776 wascomment = incomment; 777 cp = skiphash(); 778 if (cp == NULL) 779 return (LT_EOF); 780 if (newline == NULL) { 781 if (strrchr(tline, '\n') == strrchr(tline, '\r') + 1) 782 newline = newline_crlf; 783 else 784 newline = newline_unix; 785 } 786 if (*cp == '\0') { 787 retval = LT_PLAIN; 788 goto done; 789 } 790 keyword = tline + (cp - tline); 791 if ((cp = matchsym("ifdef", keyword)) != NULL || 792 (cp = matchsym("ifndef", keyword)) != NULL) { 793 cp = skipcomment(cp); 794 if ((cursym = findsym(&cp)) < 0) 795 retval = LT_IF; 796 else { 797 retval = (keyword[2] == 'n') 798 ? LT_FALSE : LT_TRUE; 799 if (value[cursym] == NULL) 800 retval = (retval == LT_TRUE) 801 ? LT_FALSE : LT_TRUE; 802 if (ignore[cursym]) 803 retval = (retval == LT_TRUE) 804 ? LT_TRUEI : LT_FALSEI; 805 } 806 } else if ((cp = matchsym("if", keyword)) != NULL) 807 retval = ifeval(&cp); 808 else if ((cp = matchsym("elif", keyword)) != NULL) 809 retval = linetype_if2elif(ifeval(&cp)); 810 else if ((cp = matchsym("else", keyword)) != NULL) 811 retval = LT_ELSE; 812 else if ((cp = matchsym("endif", keyword)) != NULL) 813 retval = LT_ENDIF; 814 else { 815 cp = skipsym(keyword); 816 /* no way can we deal with a continuation inside a keyword */ 817 if (strncmp(cp, "\\\r\n", 3) == 0 || 818 strncmp(cp, "\\\n", 2) == 0) 819 Eioccc(); 820 cp = skipline(cp); 821 retval = LT_PLAIN; 822 goto done; 823 } 824 cp = skipcomment(cp); 825 if (*cp != '\0') { 826 cp = skipline(cp); 827 if (retval == LT_TRUE || retval == LT_FALSE || 828 retval == LT_TRUEI || retval == LT_FALSEI) 829 retval = LT_IF; 830 if (retval == LT_ELTRUE || retval == LT_ELFALSE) 831 retval = LT_ELIF; 832 } 833 /* the following can happen if the last line of the file lacks a 834 newline or if there is too much whitespace in a directive */ 835 if (linestate == LS_HASH) { 836 long len = cp - tline; 837 if (fgets(tline + len, MAXLINE - len, input) == NULL) { 838 if (ferror(input)) 839 err(2, "can't read %s", filename); 840 /* append the missing newline at eof */ 841 strcpy(tline + len, newline); 842 cp += strlen(newline); 843 linestate = LS_START; 844 } else { 845 linestate = LS_DIRTY; 846 } 847 } 848 if (retval != LT_PLAIN && (wascomment || linestate != LS_START)) { 849 retval = linetype_2dodgy(retval); 850 linestate = LS_DIRTY; 851 } 852 done: 853 debug("parser line %d state %s comment %s line", linenum, 854 comment_name[incomment], linestate_name[linestate]); 855 return (retval); 856 } 857 858 /* 859 * These are the binary operators that are supported by the expression 860 * evaluator. 861 */ 862 static Linetype op_strict(long *p, long v, Linetype at, Linetype bt) { 863 if(at == LT_IF || bt == LT_IF) return (LT_IF); 864 return (*p = v, v ? LT_TRUE : LT_FALSE); 865 } 866 static Linetype op_lt(long *p, Linetype at, long a, Linetype bt, long b) { 867 return op_strict(p, a < b, at, bt); 868 } 869 static Linetype op_gt(long *p, Linetype at, long a, Linetype bt, long b) { 870 return op_strict(p, a > b, at, bt); 871 } 872 static Linetype op_le(long *p, Linetype at, long a, Linetype bt, long b) { 873 return op_strict(p, a <= b, at, bt); 874 } 875 static Linetype op_ge(long *p, Linetype at, long a, Linetype bt, long b) { 876 return op_strict(p, a >= b, at, bt); 877 } 878 static Linetype op_eq(long *p, Linetype at, long a, Linetype bt, long b) { 879 return op_strict(p, a == b, at, bt); 880 } 881 static Linetype op_ne(long *p, Linetype at, long a, Linetype bt, long b) { 882 return op_strict(p, a != b, at, bt); 883 } 884 static Linetype op_or(long *p, Linetype at, long a, Linetype bt, long b) { 885 if (!strictlogic && (at == LT_TRUE || bt == LT_TRUE)) 886 return (*p = 1, LT_TRUE); 887 return op_strict(p, a || b, at, bt); 888 } 889 static Linetype op_and(long *p, Linetype at, long a, Linetype bt, long b) { 890 if (!strictlogic && (at == LT_FALSE || bt == LT_FALSE)) 891 return (*p = 0, LT_FALSE); 892 return op_strict(p, a && b, at, bt); 893 } 894 895 /* 896 * An evaluation function takes three arguments, as follows: (1) a pointer to 897 * an element of the precedence table which lists the operators at the current 898 * level of precedence; (2) a pointer to an integer which will receive the 899 * value of the expression; and (3) a pointer to a char* that points to the 900 * expression to be evaluated and that is updated to the end of the expression 901 * when evaluation is complete. The function returns LT_FALSE if the value of 902 * the expression is zero, LT_TRUE if it is non-zero, LT_IF if the expression 903 * depends on an unknown symbol, or LT_ERROR if there is a parse failure. 904 */ 905 struct ops; 906 907 typedef Linetype eval_fn(const struct ops *, long *, const char **); 908 909 static eval_fn eval_table, eval_unary; 910 911 /* 912 * The precedence table. Expressions involving binary operators are evaluated 913 * in a table-driven way by eval_table. When it evaluates a subexpression it 914 * calls the inner function with its first argument pointing to the next 915 * element of the table. Innermost expressions have special non-table-driven 916 * handling. 917 */ 918 struct op { 919 const char *str; 920 Linetype (*fn)(long *, Linetype, long, Linetype, long); 921 }; 922 struct ops { 923 eval_fn *inner; 924 struct op op[5]; 925 }; 926 static const struct ops eval_ops[] = { 927 { eval_table, { { "||", op_or } } }, 928 { eval_table, { { "&&", op_and } } }, 929 { eval_table, { { "==", op_eq }, 930 { "!=", op_ne } } }, 931 { eval_unary, { { "<=", op_le }, 932 { ">=", op_ge }, 933 { "<", op_lt }, 934 { ">", op_gt } } } 935 }; 936 937 /* Current operator precedence level */ 938 static long prec(const struct ops *ops) 939 { 940 return (ops - eval_ops); 941 } 942 943 /* 944 * Function for evaluating the innermost parts of expressions, 945 * viz. !expr (expr) number defined(symbol) symbol 946 * We reset the constexpr flag in the last two cases. 947 */ 948 static Linetype 949 eval_unary(const struct ops *ops, long *valp, const char **cpp) 950 { 951 const char *cp; 952 char *ep; 953 int sym; 954 bool defparen; 955 Linetype lt; 956 957 cp = skipcomment(*cpp); 958 if (*cp == '!') { 959 debug("eval%d !", prec(ops)); 960 cp++; 961 lt = eval_unary(ops, valp, &cp); 962 if (lt == LT_ERROR) 963 return (LT_ERROR); 964 if (lt != LT_IF) { 965 *valp = !*valp; 966 lt = *valp ? LT_TRUE : LT_FALSE; 967 } 968 } else if (*cp == '(') { 969 cp++; 970 debug("eval%d (", prec(ops)); 971 lt = eval_table(eval_ops, valp, &cp); 972 if (lt == LT_ERROR) 973 return (LT_ERROR); 974 cp = skipcomment(cp); 975 if (*cp++ != ')') 976 return (LT_ERROR); 977 } else if (isdigit((unsigned char)*cp)) { 978 debug("eval%d number", prec(ops)); 979 *valp = strtol(cp, &ep, 0); 980 if (ep == cp) 981 return (LT_ERROR); 982 lt = *valp ? LT_TRUE : LT_FALSE; 983 cp = ep; 984 } else if (matchsym("defined", cp) != NULL) { 985 cp = skipcomment(cp+7); 986 if (*cp == '(') { 987 cp = skipcomment(cp+1); 988 defparen = true; 989 } else { 990 defparen = false; 991 } 992 sym = findsym(&cp); 993 cp = skipcomment(cp); 994 if (defparen && *cp++ != ')') { 995 debug("eval%d defined missing ')'", prec(ops)); 996 return (LT_ERROR); 997 } 998 if (sym < 0) { 999 debug("eval%d defined unknown", prec(ops)); 1000 lt = LT_IF; 1001 } else { 1002 debug("eval%d defined %s", prec(ops), symname[sym]); 1003 *valp = (value[sym] != NULL); 1004 lt = *valp ? LT_TRUE : LT_FALSE; 1005 } 1006 constexpr = false; 1007 } else if (!endsym(*cp)) { 1008 debug("eval%d symbol", prec(ops)); 1009 sym = findsym(&cp); 1010 if (sym < 0) { 1011 lt = LT_IF; 1012 cp = skipargs(cp); 1013 } else if (value[sym] == NULL) { 1014 *valp = 0; 1015 lt = LT_FALSE; 1016 } else { 1017 *valp = strtol(value[sym], &ep, 0); 1018 if (*ep != '\0' || ep == value[sym]) 1019 return (LT_ERROR); 1020 lt = *valp ? LT_TRUE : LT_FALSE; 1021 cp = skipargs(cp); 1022 } 1023 constexpr = false; 1024 } else { 1025 debug("eval%d bad expr", prec(ops)); 1026 return (LT_ERROR); 1027 } 1028 1029 *cpp = cp; 1030 debug("eval%d = %d", prec(ops), *valp); 1031 return (lt); 1032 } 1033 1034 /* 1035 * Table-driven evaluation of binary operators. 1036 */ 1037 static Linetype 1038 eval_table(const struct ops *ops, long *valp, const char **cpp) 1039 { 1040 const struct op *op; 1041 const char *cp; 1042 long val; 1043 Linetype lt, rt; 1044 1045 debug("eval%d", prec(ops)); 1046 cp = *cpp; 1047 lt = ops->inner(ops+1, valp, &cp); 1048 if (lt == LT_ERROR) 1049 return (LT_ERROR); 1050 for (;;) { 1051 cp = skipcomment(cp); 1052 for (op = ops->op; op->str != NULL; op++) 1053 if (strncmp(cp, op->str, strlen(op->str)) == 0) 1054 break; 1055 if (op->str == NULL) 1056 break; 1057 cp += strlen(op->str); 1058 debug("eval%d %s", prec(ops), op->str); 1059 rt = ops->inner(ops+1, &val, &cp); 1060 if (rt == LT_ERROR) 1061 return (LT_ERROR); 1062 lt = op->fn(valp, lt, *valp, rt, val); 1063 } 1064 1065 *cpp = cp; 1066 debug("eval%d = %d", prec(ops), *valp); 1067 debug("eval%d lt = %s", prec(ops), linetype_name[lt]); 1068 return (lt); 1069 } 1070 1071 /* 1072 * Evaluate the expression on a #if or #elif line. If we can work out 1073 * the result we return LT_TRUE or LT_FALSE accordingly, otherwise we 1074 * return just a generic LT_IF. 1075 */ 1076 static Linetype 1077 ifeval(const char **cpp) 1078 { 1079 Linetype ret; 1080 long val = 0; 1081 1082 debug("eval %s", *cpp); 1083 constexpr = killconsts ? false : true; 1084 ret = eval_table(eval_ops, &val, cpp); 1085 debug("eval = %d", val); 1086 return (constexpr ? LT_IF : ret == LT_ERROR ? LT_IF : ret); 1087 } 1088 1089 /* 1090 * Read a line and examine its initial part to determine if it is a 1091 * preprocessor directive. Returns NULL on EOF, or a pointer to a 1092 * preprocessor directive name, or a pointer to the zero byte at the 1093 * end of the line. 1094 */ 1095 static const char * 1096 skiphash(void) 1097 { 1098 const char *cp; 1099 1100 linenum++; 1101 if (fgets(tline, MAXLINE, input) == NULL) { 1102 if (ferror(input)) 1103 err(2, "can't read %s", filename); 1104 else 1105 return (NULL); 1106 } 1107 cp = skipcomment(tline); 1108 if (linestate == LS_START && *cp == '#') { 1109 linestate = LS_HASH; 1110 return (skipcomment(cp + 1)); 1111 } else if (*cp == '\0') { 1112 return (cp); 1113 } else { 1114 return (skipline(cp)); 1115 } 1116 } 1117 1118 /* 1119 * Mark a line dirty and consume the rest of it, keeping track of the 1120 * lexical state. 1121 */ 1122 static const char * 1123 skipline(const char *cp) 1124 { 1125 if (*cp != '\0') 1126 linestate = LS_DIRTY; 1127 while (*cp != '\0') 1128 cp = skipcomment(cp + 1); 1129 return (cp); 1130 } 1131 1132 /* 1133 * Skip over comments, strings, and character literals and stop at the 1134 * next character position that is not whitespace. Between calls we keep 1135 * the comment state in the global variable incomment, and we also adjust 1136 * the global variable linestate when we see a newline. 1137 * XXX: doesn't cope with the buffer splitting inside a state transition. 1138 */ 1139 static const char * 1140 skipcomment(const char *cp) 1141 { 1142 if (text || ignoring[depth]) { 1143 for (; isspace((unsigned char)*cp); cp++) 1144 if (*cp == '\n') 1145 linestate = LS_START; 1146 return (cp); 1147 } 1148 while (*cp != '\0') 1149 /* don't reset to LS_START after a line continuation */ 1150 if (strncmp(cp, "\\\r\n", 3) == 0) 1151 cp += 3; 1152 else if (strncmp(cp, "\\\n", 2) == 0) 1153 cp += 2; 1154 else switch (incomment) { 1155 case NO_COMMENT: 1156 if (strncmp(cp, "/\\\r\n", 4) == 0) { 1157 incomment = STARTING_COMMENT; 1158 cp += 4; 1159 } else if (strncmp(cp, "/\\\n", 3) == 0) { 1160 incomment = STARTING_COMMENT; 1161 cp += 3; 1162 } else if (strncmp(cp, "/*", 2) == 0) { 1163 incomment = C_COMMENT; 1164 cp += 2; 1165 } else if (strncmp(cp, "//", 2) == 0) { 1166 incomment = CXX_COMMENT; 1167 cp += 2; 1168 } else if (strncmp(cp, "\'", 1) == 0) { 1169 incomment = CHAR_LITERAL; 1170 linestate = LS_DIRTY; 1171 cp += 1; 1172 } else if (strncmp(cp, "\"", 1) == 0) { 1173 incomment = STRING_LITERAL; 1174 linestate = LS_DIRTY; 1175 cp += 1; 1176 } else if (strncmp(cp, "\n", 1) == 0) { 1177 linestate = LS_START; 1178 cp += 1; 1179 } else if (strchr(" \r\t", *cp) != NULL) { 1180 cp += 1; 1181 } else 1182 return (cp); 1183 continue; 1184 case CXX_COMMENT: 1185 if (strncmp(cp, "\n", 1) == 0) { 1186 incomment = NO_COMMENT; 1187 linestate = LS_START; 1188 } 1189 cp += 1; 1190 continue; 1191 case CHAR_LITERAL: 1192 case STRING_LITERAL: 1193 if ((incomment == CHAR_LITERAL && cp[0] == '\'') || 1194 (incomment == STRING_LITERAL && cp[0] == '\"')) { 1195 incomment = NO_COMMENT; 1196 cp += 1; 1197 } else if (cp[0] == '\\') { 1198 if (cp[1] == '\0') 1199 cp += 1; 1200 else 1201 cp += 2; 1202 } else if (strncmp(cp, "\n", 1) == 0) { 1203 if (incomment == CHAR_LITERAL) 1204 error("unterminated char literal"); 1205 else 1206 error("unterminated string literal"); 1207 } else 1208 cp += 1; 1209 continue; 1210 case C_COMMENT: 1211 if (strncmp(cp, "*\\\r\n", 4) == 0) { 1212 incomment = FINISHING_COMMENT; 1213 cp += 4; 1214 } else if (strncmp(cp, "*\\\n", 3) == 0) { 1215 incomment = FINISHING_COMMENT; 1216 cp += 3; 1217 } else if (strncmp(cp, "*/", 2) == 0) { 1218 incomment = NO_COMMENT; 1219 cp += 2; 1220 } else 1221 cp += 1; 1222 continue; 1223 case STARTING_COMMENT: 1224 if (*cp == '*') { 1225 incomment = C_COMMENT; 1226 cp += 1; 1227 } else if (*cp == '/') { 1228 incomment = CXX_COMMENT; 1229 cp += 1; 1230 } else { 1231 incomment = NO_COMMENT; 1232 linestate = LS_DIRTY; 1233 } 1234 continue; 1235 case FINISHING_COMMENT: 1236 if (*cp == '/') { 1237 incomment = NO_COMMENT; 1238 cp += 1; 1239 } else 1240 incomment = C_COMMENT; 1241 continue; 1242 default: 1243 abort(); /* bug */ 1244 } 1245 return (cp); 1246 } 1247 1248 /* 1249 * Skip macro arguments. 1250 */ 1251 static const char * 1252 skipargs(const char *cp) 1253 { 1254 const char *ocp = cp; 1255 int level = 0; 1256 cp = skipcomment(cp); 1257 if (*cp != '(') 1258 return (cp); 1259 do { 1260 if (*cp == '(') 1261 level++; 1262 if (*cp == ')') 1263 level--; 1264 cp = skipcomment(cp+1); 1265 } while (level != 0 && *cp != '\0'); 1266 if (level == 0) 1267 return (cp); 1268 else 1269 /* Rewind and re-detect the syntax error later. */ 1270 return (ocp); 1271 } 1272 1273 /* 1274 * Skip over an identifier. 1275 */ 1276 static const char * 1277 skipsym(const char *cp) 1278 { 1279 while (!endsym(*cp)) 1280 ++cp; 1281 return (cp); 1282 } 1283 1284 /* 1285 * Skip whitespace and take a copy of any following identifier. 1286 */ 1287 static const char * 1288 getsym(const char **cpp) 1289 { 1290 const char *cp = *cpp, *sym; 1291 1292 cp = skipcomment(cp); 1293 cp = skipsym(sym = cp); 1294 if (cp == sym) 1295 return NULL; 1296 *cpp = cp; 1297 return (xstrdup(sym, cp)); 1298 } 1299 1300 /* 1301 * Check that s (a symbol) matches the start of t, and that the 1302 * following character in t is not a symbol character. Returns a 1303 * pointer to the following character in t if there is a match, 1304 * otherwise NULL. 1305 */ 1306 static const char * 1307 matchsym(const char *s, const char *t) 1308 { 1309 while (*s != '\0' && *t != '\0') 1310 if (*s != *t) 1311 return (NULL); 1312 else 1313 ++s, ++t; 1314 if (*s == '\0' && endsym(*t)) 1315 return(t); 1316 else 1317 return(NULL); 1318 } 1319 1320 /* 1321 * Look for the symbol in the symbol table. If it is found, we return 1322 * the symbol table index, else we return -1. 1323 */ 1324 static int 1325 findsym(const char **strp) 1326 { 1327 const char *str; 1328 int symind; 1329 1330 str = *strp; 1331 *strp = skipsym(str); 1332 if (symlist) { 1333 if (*strp == str) 1334 return (-1); 1335 if (symdepth && firstsym) 1336 printf("%s%3d", zerosyms ? "" : "\n", depth); 1337 firstsym = zerosyms = false; 1338 printf("%s%.*s%s", 1339 symdepth ? " " : "", 1340 (int)(*strp-str), str, 1341 symdepth ? "" : "\n"); 1342 /* we don't care about the value of the symbol */ 1343 return (0); 1344 } 1345 for (symind = 0; symind < nsyms; ++symind) { 1346 if (matchsym(symname[symind], str) != NULL) { 1347 debugsym("findsym", symind); 1348 return (symind); 1349 } 1350 } 1351 return (-1); 1352 } 1353 1354 /* 1355 * Resolve indirect symbol values to their final definitions. 1356 */ 1357 static void 1358 indirectsym(void) 1359 { 1360 const char *cp; 1361 int changed, sym, ind; 1362 1363 do { 1364 changed = 0; 1365 for (sym = 0; sym < nsyms; ++sym) { 1366 if (value[sym] == NULL) 1367 continue; 1368 cp = value[sym]; 1369 ind = findsym(&cp); 1370 if (ind == -1 || ind == sym || 1371 *cp != '\0' || 1372 value[ind] == NULL || 1373 value[ind] == value[sym]) 1374 continue; 1375 debugsym("indir...", sym); 1376 value[sym] = value[ind]; 1377 debugsym("...ectsym", sym); 1378 changed++; 1379 } 1380 } while (changed); 1381 } 1382 1383 /* 1384 * Add a symbol to the symbol table, specified with the format sym=val 1385 */ 1386 static void 1387 addsym1(bool ignorethis, bool definethis, char *symval) 1388 { 1389 const char *sym, *val; 1390 1391 sym = symval; 1392 val = skipsym(sym); 1393 if (definethis && *val == '=') { 1394 symval[val - sym] = '\0'; 1395 val = val + 1; 1396 } else if (*val == '\0') { 1397 val = definethis ? "1" : NULL; 1398 } else { 1399 usage(); 1400 } 1401 addsym2(ignorethis, sym, val); 1402 } 1403 1404 /* 1405 * Add a symbol to the symbol table. 1406 */ 1407 static void 1408 addsym2(bool ignorethis, const char *sym, const char *val) 1409 { 1410 const char *cp = sym; 1411 int symind; 1412 1413 symind = findsym(&cp); 1414 if (symind < 0) { 1415 if (nsyms >= MAXSYMS) 1416 errx(2, "too many symbols"); 1417 symind = nsyms++; 1418 } 1419 ignore[symind] = ignorethis; 1420 symname[symind] = sym; 1421 value[symind] = val; 1422 debugsym("addsym", symind); 1423 } 1424 1425 static void 1426 debugsym(const char *why, int symind) 1427 { 1428 debug("%s %s%c%s", why, symname[symind], 1429 value[symind] ? '=' : ' ', 1430 value[symind] ? value[symind] : "undef"); 1431 } 1432 1433 /* 1434 * Add symbols to the symbol table from a file containing 1435 * #define and #undef preprocessor directives. 1436 */ 1437 static void 1438 defundefile(const char *fn) 1439 { 1440 filename = fn; 1441 input = fopen(fn, "rb"); 1442 if (input == NULL) 1443 err(2, "can't open %s", fn); 1444 linenum = 0; 1445 while (defundef()) 1446 ; 1447 if (ferror(input)) 1448 err(2, "can't read %s", filename); 1449 else 1450 fclose(input); 1451 if (incomment) 1452 error("EOF in comment"); 1453 } 1454 1455 /* 1456 * Read and process one #define or #undef directive 1457 */ 1458 static bool 1459 defundef(void) 1460 { 1461 const char *cp, *kw, *sym, *val, *end; 1462 1463 cp = skiphash(); 1464 if (cp == NULL) 1465 return (false); 1466 if (*cp == '\0') 1467 goto done; 1468 /* strip trailing whitespace, and do a fairly rough check to 1469 avoid unsupported multi-line preprocessor directives */ 1470 end = cp + strlen(cp); 1471 while (end > tline && strchr(" \t\n\r", end[-1]) != NULL) 1472 --end; 1473 if (end > tline && end[-1] == '\\') 1474 Eioccc(); 1475 1476 kw = cp; 1477 if ((cp = matchsym("define", kw)) != NULL) { 1478 sym = getsym(&cp); 1479 if (sym == NULL) 1480 error("missing macro name in #define"); 1481 if (*cp == '(') { 1482 val = "1"; 1483 } else { 1484 cp = skipcomment(cp); 1485 val = (cp < end) ? xstrdup(cp, end) : ""; 1486 } 1487 debug("#define"); 1488 addsym2(false, sym, val); 1489 } else if ((cp = matchsym("undef", kw)) != NULL) { 1490 sym = getsym(&cp); 1491 if (sym == NULL) 1492 error("missing macro name in #undef"); 1493 cp = skipcomment(cp); 1494 debug("#undef"); 1495 addsym2(false, sym, NULL); 1496 } else { 1497 error("unrecognized preprocessor directive"); 1498 } 1499 skipline(cp); 1500 done: 1501 debug("parser line %d state %s comment %s line", linenum, 1502 comment_name[incomment], linestate_name[linestate]); 1503 return (true); 1504 } 1505 1506 /* 1507 * Concatenate two strings into new memory, checking for failure. 1508 */ 1509 static char * 1510 astrcat(const char *s1, const char *s2) 1511 { 1512 char *s; 1513 int len; 1514 size_t size; 1515 1516 len = snprintf(NULL, 0, "%s%s", s1, s2); 1517 if (len < 0) 1518 err(2, "snprintf"); 1519 size = (size_t)len + 1; 1520 s = (char *)malloc(size); 1521 if (s == NULL) 1522 err(2, "malloc"); 1523 snprintf(s, size, "%s%s", s1, s2); 1524 return (s); 1525 } 1526 1527 /* 1528 * Duplicate a segment of a string, checking for failure. 1529 */ 1530 static const char * 1531 xstrdup(const char *start, const char *end) 1532 { 1533 size_t n; 1534 char *s; 1535 1536 if (end < start) abort(); /* bug */ 1537 n = (size_t)(end - start) + 1; 1538 s = malloc(n); 1539 if (s == NULL) 1540 err(2, "malloc"); 1541 snprintf(s, n, "%s", start); 1542 return (s); 1543 } 1544 1545 /* 1546 * Diagnostics. 1547 */ 1548 static void 1549 debug(const char *msg, ...) 1550 { 1551 va_list ap; 1552 1553 if (debugging) { 1554 va_start(ap, msg); 1555 vwarnx(msg, ap); 1556 va_end(ap); 1557 } 1558 } 1559 1560 static void 1561 error(const char *msg) 1562 { 1563 if (depth == 0) 1564 warnx("%s: %d: %s", filename, linenum, msg); 1565 else 1566 warnx("%s: %d: %s (#if line %d depth %d)", 1567 filename, linenum, msg, stifline[depth], depth); 1568 closeio(); 1569 errx(2, "output may be truncated"); 1570 } 1571