1 /* 2 * Copyright (c) 2002 - 2020 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: 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 */ 141 142 /* 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 * C17/18 allow 63 characters per macro name, but up to 127 arbitrarily large 150 * parameters. 151 */ 152 struct macro { 153 RB_ENTRY(macro) entry; 154 const char *name; 155 const char *value; 156 bool ignore; /* -iDsym or -iUsym */ 157 }; 158 159 static int 160 macro_cmp(struct macro *a, struct macro *b) 161 { 162 return (strcmp(a->name, b->name)); 163 } 164 165 static RB_HEAD(MACROMAP, macro) macro_tree = RB_INITIALIZER(¯o_tree); 166 RB_GENERATE_STATIC(MACROMAP, macro, entry, macro_cmp); 167 168 /* 169 * Globals. 170 */ 171 172 static bool compblank; /* -B: compress blank lines */ 173 static bool lnblank; /* -b: blank deleted lines */ 174 static bool complement; /* -c: do the complement */ 175 static bool debugging; /* -d: debugging reports */ 176 static bool inplace; /* -m: modify in place */ 177 static bool iocccok; /* -e: fewer IOCCC errors */ 178 static bool strictlogic; /* -K: keep ambiguous #ifs */ 179 static bool killconsts; /* -k: eval constant #ifs */ 180 static bool lnnum; /* -n: add #line directives */ 181 static bool symlist; /* -s: output symbol list */ 182 static bool symdepth; /* -S: output symbol depth */ 183 static bool text; /* -t: this is a text file */ 184 185 static FILE *input; /* input file pointer */ 186 static const char *filename; /* input file name */ 187 static int linenum; /* current line number */ 188 static const char *linefile; /* file name for #line */ 189 static FILE *output; /* output file pointer */ 190 static const char *ofilename; /* output file name */ 191 static const char *backext; /* backup extension */ 192 static char *tempname; /* avoid splatting input */ 193 194 static char tline[MAXLINE+EDITSLOP];/* input buffer plus space */ 195 static char *keyword; /* used for editing #elif's */ 196 197 /* 198 * When processing a file, the output's newline style will match the 199 * input's, and unifdef correctly handles CRLF or LF endings whatever 200 * the platform's native style. The stdio streams are opened in binary 201 * mode to accommodate platforms whose native newline style is CRLF. 202 * When the output isn't a processed input file (when it is error / 203 * debug / diagnostic messages) then unifdef uses native line endings. 204 */ 205 206 static const char *newline; /* input file format */ 207 static const char newline_unix[] = "\n"; 208 static const char newline_crlf[] = "\r\n"; 209 210 static Comment_state incomment; /* comment parser state */ 211 static Line_state linestate; /* #if line parser state */ 212 static Ifstate ifstate[MAXDEPTH]; /* #if processor state */ 213 static bool ignoring[MAXDEPTH]; /* ignore comments state */ 214 static int stifline[MAXDEPTH]; /* start of current #if */ 215 static int depth; /* current #if nesting */ 216 static int delcount; /* count of deleted lines */ 217 static unsigned blankcount; /* count of blank lines */ 218 static unsigned blankmax; /* maximum recent blankcount */ 219 static bool constexpr; /* constant #if expression */ 220 static bool zerosyms; /* to format symdepth output */ 221 static bool firstsym; /* ditto */ 222 223 static int exitmode; /* exit status mode */ 224 static int exitstat; /* program exit status */ 225 static bool altered; /* was this file modified? */ 226 227 static void addsym1(bool, bool, char *); 228 static void addsym2(bool, const char *, const char *); 229 static char *astrcat(const char *, const char *); 230 static void cleantemp(void); 231 static void closeio(void); 232 static void debug(const char *, ...); 233 static void debugsym(const char *, const struct macro *); 234 static bool defundef(void); 235 static void defundefile(const char *); 236 static void done(void); 237 static void error(const char *); 238 static struct macro *findsym(const char **); 239 static void flushline(bool); 240 static void hashline(void); 241 static void help(void); 242 static Linetype ifeval(const char **); 243 static void ignoreoff(void); 244 static void ignoreon(void); 245 static void indirectsym(void); 246 static void keywordedit(const char *); 247 static const char *matchsym(const char *, const char *); 248 static void nest(void); 249 static Linetype parseline(void); 250 static void process(void); 251 static void processinout(const char *, const char *); 252 static const char *skipargs(const char *); 253 static const char *skipcomment(const char *); 254 static const char *skiphash(void); 255 static const char *skipline(const char *); 256 static const char *skipsym(const char *); 257 static void state(Ifstate); 258 static void unnest(void); 259 static void usage(void); 260 static void version(void); 261 static const char *xstrdup(const char *, const char *); 262 263 #define endsym(c) (!isalnum((unsigned char)c) && c != '_') 264 265 /* 266 * The main program. 267 */ 268 int 269 main(int argc, char *argv[]) 270 { 271 int opt; 272 273 while ((opt = getopt(argc, argv, "i:D:U:f:I:M:o:x:bBcdehKklmnsStV")) != -1) 274 switch (opt) { 275 case 'i': /* treat stuff controlled by these symbols as text */ 276 /* 277 * For strict backwards-compatibility the U or D 278 * should be immediately after the -i but it doesn't 279 * matter much if we relax that requirement. 280 */ 281 opt = *optarg++; 282 if (opt == 'D') 283 addsym1(true, true, optarg); 284 else if (opt == 'U') 285 addsym1(true, false, optarg); 286 else 287 usage(); 288 break; 289 case 'D': /* define a symbol */ 290 addsym1(false, true, optarg); 291 break; 292 case 'U': /* undef a symbol */ 293 addsym1(false, false, optarg); 294 break; 295 case 'I': /* no-op for compatibility with cpp */ 296 break; 297 case 'b': /* blank deleted lines instead of omitting them */ 298 case 'l': /* backwards compatibility */ 299 lnblank = true; 300 break; 301 case 'B': /* compress blank lines around removed section */ 302 compblank = true; 303 break; 304 case 'c': /* treat -D as -U and vice versa */ 305 complement = true; 306 break; 307 case 'd': 308 debugging = true; 309 break; 310 case 'e': /* fewer errors from dodgy lines */ 311 iocccok = true; 312 break; 313 case 'f': /* definitions file */ 314 defundefile(optarg); 315 break; 316 case 'h': 317 help(); 318 break; 319 case 'K': /* keep ambiguous #ifs */ 320 strictlogic = true; 321 break; 322 case 'k': /* process constant #ifs */ 323 killconsts = true; 324 break; 325 case 'm': /* modify in place */ 326 inplace = true; 327 break; 328 case 'M': /* modify in place and keep backup */ 329 inplace = true; 330 if (strlen(optarg) > 0) 331 backext = optarg; 332 break; 333 case 'n': /* add #line directive after deleted lines */ 334 lnnum = true; 335 break; 336 case 'o': /* output to a file */ 337 ofilename = optarg; 338 break; 339 case 's': /* only output list of symbols that control #ifs */ 340 symlist = true; 341 break; 342 case 'S': /* list symbols with their nesting depth */ 343 symlist = symdepth = true; 344 break; 345 case 't': /* don't parse C comments */ 346 text = true; 347 break; 348 case 'V': 349 version(); 350 break; 351 case 'x': 352 exitmode = atoi(optarg); 353 if(exitmode < 0 || exitmode > 2) 354 usage(); 355 break; 356 default: 357 usage(); 358 } 359 argc -= optind; 360 argv += optind; 361 if (compblank && lnblank) 362 errx(2, "-B and -b are mutually exclusive"); 363 if (symlist && (ofilename != NULL || inplace || argc > 1)) 364 errx(2, "-s only works with one input file"); 365 if (argc > 1 && ofilename != NULL) 366 errx(2, "-o cannot be used with multiple input files"); 367 if (argc > 1 && !inplace) 368 errx(2, "multiple input files require -m or -M"); 369 if (argc == 0 && inplace) 370 errx(2, "-m requires an input file"); 371 if (argc == 0) 372 argc = 1; 373 if (argc == 1 && !inplace && ofilename == NULL) 374 ofilename = "-"; 375 indirectsym(); 376 377 atexit(cleantemp); 378 if (ofilename != NULL) 379 processinout(*argv, ofilename); 380 else while (argc-- > 0) { 381 processinout(*argv, *argv); 382 argv++; 383 } 384 switch(exitmode) { 385 case(0): exit(exitstat); 386 case(1): exit(!exitstat); 387 case(2): exit(0); 388 default: abort(); /* bug */ 389 } 390 } 391 392 /* 393 * File logistics. 394 */ 395 static void 396 processinout(const char *ifn, const char *ofn) 397 { 398 struct stat st; 399 400 if (ifn == NULL || strcmp(ifn, "-") == 0) { 401 filename = "[stdin]"; 402 linefile = NULL; 403 input = fbinmode(stdin); 404 } else { 405 filename = ifn; 406 linefile = ifn; 407 input = fopen(ifn, "rb"); 408 if (input == NULL) 409 err(2, "can't open %s", ifn); 410 } 411 if (strcmp(ofn, "-") == 0) { 412 output = fbinmode(stdout); 413 process(); 414 return; 415 } 416 if (stat(ofn, &st) < 0) { 417 output = fopen(ofn, "wb"); 418 if (output == NULL) 419 err(2, "can't create %s", ofn); 420 process(); 421 return; 422 } 423 424 tempname = astrcat(ofn, ".XXXXXX"); 425 output = mktempmode(tempname, st.st_mode); 426 if (output == NULL) 427 err(2, "can't create %s", tempname); 428 429 process(); 430 431 if (backext != NULL) { 432 char *backname = astrcat(ofn, backext); 433 if (rename(ofn, backname) < 0) 434 err(2, "can't rename \"%s\" to \"%s\"", ofn, backname); 435 free(backname); 436 } 437 /* leave file unmodified if unifdef made no changes */ 438 if (!altered && backext == NULL) { 439 if (remove(tempname) < 0) 440 warn("can't remove \"%s\"", tempname); 441 } else if (replace(tempname, ofn) < 0) 442 err(2, "can't rename \"%s\" to \"%s\"", tempname, ofn); 443 free(tempname); 444 tempname = NULL; 445 } 446 447 /* 448 * For cleaning up if there is an error. 449 */ 450 static void 451 cleantemp(void) 452 { 453 if (tempname != NULL) 454 remove(tempname); 455 } 456 457 /* 458 * Self-identification functions. 459 */ 460 461 static void 462 version(void) 463 { 464 const char *c = copyright; 465 for (;;) { 466 while (*++c != '$') 467 if (*c == '\0') 468 exit(0); 469 while (*++c != '$') 470 putc(*c, stderr); 471 putc('\n', stderr); 472 } 473 } 474 475 static void 476 synopsis(FILE *fp) 477 { 478 fprintf(fp, 479 "usage: unifdef [-bBcdehKkmnsStV] [-x{012}] [-Mext] [-opath] \\\n" 480 " [-[i]Dsym[=val]] [-[i]Usym] [-fpath] ... [file] ...\n"); 481 } 482 483 static void 484 usage(void) 485 { 486 synopsis(stderr); 487 exit(2); 488 } 489 490 static void 491 help(void) 492 { 493 synopsis(stdout); 494 printf( 495 " -Dsym=val define preprocessor symbol with given value\n" 496 " -Dsym define preprocessor symbol with value 1\n" 497 " -Usym preprocessor symbol is undefined\n" 498 " -iDsym=val \\ ignore C strings and comments\n" 499 " -iDsym ) in sections controlled by these\n" 500 " -iUsym / preprocessor symbols\n" 501 " -fpath file containing #define and #undef directives\n" 502 " -b blank lines instead of deleting them\n" 503 " -B compress blank lines around deleted section\n" 504 " -c complement (invert) keep vs. delete\n" 505 " -d debugging mode\n" 506 " -e ignore multiline preprocessor directives\n" 507 " -h print help\n" 508 " -Ipath extra include file path (ignored)\n" 509 " -K disable && and || short-circuiting\n" 510 " -k process constant #if expressions\n" 511 " -Mext modify in place and keep backups\n" 512 " -m modify input files in place\n" 513 " -n add #line directives to output\n" 514 " -opath output file name\n" 515 " -S list #if control symbols with nesting\n" 516 " -s list #if control symbols\n" 517 " -t ignore C strings and comments\n" 518 " -V print version\n" 519 " -x{012} exit status mode\n" 520 ); 521 exit(0); 522 } 523 524 /* 525 * A state transition function alters the global #if processing state 526 * in a particular way. The table below is indexed by the current 527 * processing state and the type of the current line. 528 * 529 * Nesting is handled by keeping a stack of states; some transition 530 * functions increase or decrease the depth. They also maintain the 531 * ignore state on a stack. In some complicated cases they have to 532 * alter the preprocessor directive, as follows. 533 * 534 * When we have processed a group that starts off with a known-false 535 * #if/#elif sequence (which has therefore been deleted) followed by a 536 * #elif that we don't understand and therefore must keep, we edit the 537 * latter into a #if to keep the nesting correct. We use memcpy() to 538 * overwrite the 4 byte token "elif" with "if " without a '\0' byte. 539 * 540 * When we find a true #elif in a group, the following block will 541 * always be kept and the rest of the sequence after the next #elif or 542 * #else will be discarded. We edit the #elif into a #else and the 543 * following directive to #endif since this has the desired behaviour. 544 * 545 * "Dodgy" directives are split across multiple lines, the most common 546 * example being a multi-line comment hanging off the right of the 547 * directive. We can handle them correctly only if there is no change 548 * from printing to dropping (or vice versa) caused by that directive. 549 * If the directive is the first of a group we have a choice between 550 * failing with an error, or passing it through unchanged instead of 551 * evaluating it. The latter is not the default to avoid questions from 552 * users about unifdef unexpectedly leaving behind preprocessor directives. 553 */ 554 typedef void state_fn(void); 555 556 /* report an error */ 557 static void Eelif (void) { error("Inappropriate #elif"); } 558 static void Eelse (void) { error("Inappropriate #else"); } 559 static void Eendif(void) { error("Inappropriate #endif"); } 560 static void Eeof (void) { error("Premature EOF"); } 561 static void Eioccc(void) { error("Obfuscated preprocessor control line"); } 562 /* plain line handling */ 563 static void print (void) { flushline(true); } 564 static void drop (void) { flushline(false); } 565 /* output lacks group's start line */ 566 static void Strue (void) { drop(); ignoreoff(); state(IS_TRUE_PREFIX); } 567 static void Sfalse(void) { drop(); ignoreoff(); state(IS_FALSE_PREFIX); } 568 static void Selse (void) { drop(); state(IS_TRUE_ELSE); } 569 /* print/pass this block */ 570 static void Pelif (void) { print(); ignoreoff(); state(IS_PASS_MIDDLE); } 571 static void Pelse (void) { print(); state(IS_PASS_ELSE); } 572 static void Pendif(void) { print(); unnest(); } 573 /* discard this block */ 574 static void Dfalse(void) { drop(); ignoreoff(); state(IS_FALSE_TRAILER); } 575 static void Delif (void) { drop(); ignoreoff(); state(IS_FALSE_MIDDLE); } 576 static void Delse (void) { drop(); state(IS_FALSE_ELSE); } 577 static void Dendif(void) { drop(); unnest(); } 578 /* first line of group */ 579 static void Fdrop (void) { nest(); Dfalse(); } 580 static void Fpass (void) { nest(); Pelif(); } 581 static void Ftrue (void) { nest(); Strue(); } 582 static void Ffalse(void) { nest(); Sfalse(); } 583 /* variable pedantry for obfuscated lines */ 584 static void Oiffy (void) { if (!iocccok) Eioccc(); Fpass(); ignoreon(); } 585 static void Oif (void) { if (!iocccok) Eioccc(); Fpass(); } 586 static void Oelif (void) { if (!iocccok) Eioccc(); Pelif(); } 587 /* ignore comments in this block */ 588 static void Idrop (void) { Fdrop(); ignoreon(); } 589 static void Itrue (void) { Ftrue(); ignoreon(); } 590 static void Ifalse(void) { Ffalse(); ignoreon(); } 591 /* modify this line */ 592 static void Mpass (void) { memcpy(keyword, "if ", 4); Pelif(); } 593 static void Mtrue (void) { keywordedit("else"); state(IS_TRUE_MIDDLE); } 594 static void Melif (void) { keywordedit("endif"); state(IS_FALSE_TRAILER); } 595 static void Melse (void) { keywordedit("endif"); state(IS_FALSE_ELSE); } 596 597 static state_fn * const trans_table[IS_COUNT][LT_COUNT] = { 598 /* IS_OUTSIDE */ 599 { Itrue, Ifalse,Fpass, Ftrue, Ffalse,Eelif, Eelif, Eelif, Eelse, Eendif, 600 Oiffy, Oiffy, Fpass, Oif, Oif, Eelif, Eelif, Eelif, Eelse, Eendif, 601 print, done, abort }, 602 /* IS_FALSE_PREFIX */ 603 { Idrop, Idrop, Fdrop, Fdrop, Fdrop, Mpass, Strue, Sfalse,Selse, Dendif, 604 Idrop, Idrop, Fdrop, Fdrop, Fdrop, Mpass, Eioccc,Eioccc,Eioccc,Eioccc, 605 drop, Eeof, abort }, 606 /* IS_TRUE_PREFIX */ 607 { Itrue, Ifalse,Fpass, Ftrue, Ffalse,Dfalse,Dfalse,Dfalse,Delse, Dendif, 608 Oiffy, Oiffy, Fpass, Oif, Oif, Eioccc,Eioccc,Eioccc,Eioccc,Eioccc, 609 print, Eeof, abort }, 610 /* IS_PASS_MIDDLE */ 611 { Itrue, Ifalse,Fpass, Ftrue, Ffalse,Pelif, Mtrue, Delif, Pelse, Pendif, 612 Oiffy, Oiffy, Fpass, Oif, Oif, Pelif, Oelif, Oelif, Pelse, Pendif, 613 print, Eeof, abort }, 614 /* IS_FALSE_MIDDLE */ 615 { Idrop, Idrop, Fdrop, Fdrop, Fdrop, Pelif, Mtrue, Delif, Pelse, Pendif, 616 Idrop, Idrop, Fdrop, Fdrop, Fdrop, Eioccc,Eioccc,Eioccc,Eioccc,Eioccc, 617 drop, Eeof, abort }, 618 /* IS_TRUE_MIDDLE */ 619 { Itrue, Ifalse,Fpass, Ftrue, Ffalse,Melif, Melif, Melif, Melse, Pendif, 620 Oiffy, Oiffy, Fpass, Oif, Oif, Eioccc,Eioccc,Eioccc,Eioccc,Pendif, 621 print, Eeof, abort }, 622 /* IS_PASS_ELSE */ 623 { Itrue, Ifalse,Fpass, Ftrue, Ffalse,Eelif, Eelif, Eelif, Eelse, Pendif, 624 Oiffy, Oiffy, Fpass, Oif, Oif, Eelif, Eelif, Eelif, Eelse, Pendif, 625 print, Eeof, abort }, 626 /* IS_FALSE_ELSE */ 627 { Idrop, Idrop, Fdrop, Fdrop, Fdrop, Eelif, Eelif, Eelif, Eelse, Dendif, 628 Idrop, Idrop, Fdrop, Fdrop, Fdrop, Eelif, Eelif, Eelif, Eelse, Eioccc, 629 drop, Eeof, abort }, 630 /* IS_TRUE_ELSE */ 631 { Itrue, Ifalse,Fpass, Ftrue, Ffalse,Eelif, Eelif, Eelif, Eelse, Dendif, 632 Oiffy, Oiffy, Fpass, Oif, Oif, Eelif, Eelif, Eelif, Eelse, Eioccc, 633 print, Eeof, abort }, 634 /* IS_FALSE_TRAILER */ 635 { Idrop, Idrop, Fdrop, Fdrop, Fdrop, Dfalse,Dfalse,Dfalse,Delse, Dendif, 636 Idrop, Idrop, Fdrop, Fdrop, Fdrop, Dfalse,Dfalse,Dfalse,Delse, Eioccc, 637 drop, Eeof, abort } 638 /*TRUEI FALSEI IF TRUE FALSE ELIF ELTRUE ELFALSE ELSE ENDIF 639 TRUEI FALSEI IF TRUE FALSE ELIF ELTRUE ELFALSE ELSE ENDIF (DODGY) 640 PLAIN EOF ERROR */ 641 }; 642 643 /* 644 * State machine utility functions 645 */ 646 static void 647 ignoreoff(void) 648 { 649 if (depth == 0) 650 abort(); /* bug */ 651 ignoring[depth] = ignoring[depth-1]; 652 } 653 static void 654 ignoreon(void) 655 { 656 ignoring[depth] = true; 657 } 658 static void 659 keywordedit(const char *replacement) 660 { 661 snprintf(keyword, tline + sizeof(tline) - keyword, 662 "%s%s", replacement, newline); 663 altered = true; 664 print(); 665 } 666 static void 667 nest(void) 668 { 669 if (depth > MAXDEPTH-1) 670 abort(); /* bug */ 671 if (depth == MAXDEPTH-1) 672 error("Too many levels of nesting"); 673 depth += 1; 674 stifline[depth] = linenum; 675 } 676 static void 677 unnest(void) 678 { 679 if (depth == 0) 680 abort(); /* bug */ 681 depth -= 1; 682 } 683 static void 684 state(Ifstate is) 685 { 686 ifstate[depth] = is; 687 } 688 689 /* 690 * The last state transition function. When this is called, 691 * lineval == LT_EOF, so the process() loop will terminate. 692 */ 693 static void 694 done(void) 695 { 696 if (incomment) 697 error("EOF in comment"); 698 closeio(); 699 } 700 701 /* 702 * Write a line to the output or not, according to command line options. 703 * If writing fails, closeio() will print the error and exit. 704 */ 705 static void 706 flushline(bool keep) 707 { 708 if (symlist) 709 return; 710 if (keep ^ complement) { 711 bool blankline = tline[strspn(tline, " \t\r\n")] == '\0'; 712 if (blankline && compblank && blankcount != blankmax) { 713 delcount += 1; 714 blankcount += 1; 715 } else { 716 if (lnnum && delcount > 0) 717 hashline(); 718 if (fputs(tline, output) == EOF) 719 closeio(); 720 delcount = 0; 721 blankmax = blankcount = blankline ? blankcount + 1 : 0; 722 } 723 } else { 724 if (lnblank && fputs(newline, output) == EOF) 725 closeio(); 726 altered = true; 727 delcount += 1; 728 blankcount = 0; 729 } 730 if (debugging && fflush(output) == EOF) 731 closeio(); 732 } 733 734 /* 735 * Format of #line directives depends on whether we know the input filename. 736 */ 737 static void 738 hashline(void) 739 { 740 int e; 741 742 if (linefile == NULL) 743 e = fprintf(output, "#line %d%s", linenum, newline); 744 else 745 e = fprintf(output, "#line %d \"%s\"%s", 746 linenum, linefile, newline); 747 if (e < 0) 748 closeio(); 749 } 750 751 /* 752 * Flush the output and handle errors. 753 */ 754 static void 755 closeio(void) 756 { 757 /* Tidy up after findsym(). */ 758 if (symdepth && !zerosyms) 759 printf("\n"); 760 if (output != NULL && (ferror(output) || fclose(output) == EOF)) 761 err(2, "%s: can't write to output", filename); 762 fclose(input); 763 } 764 765 /* 766 * The driver for the state machine. 767 */ 768 static void 769 process(void) 770 { 771 Linetype lineval = LT_PLAIN; 772 /* When compressing blank lines, act as if the file 773 is preceded by a large number of blank lines. */ 774 blankmax = blankcount = 1000; 775 zerosyms = true; 776 newline = NULL; 777 linenum = 0; 778 altered = false; 779 while (lineval != LT_EOF) { 780 lineval = parseline(); 781 trans_table[ifstate[depth]][lineval](); 782 debug("process line %d %s -> %s depth %d", 783 linenum, linetype_name[lineval], 784 ifstate_name[ifstate[depth]], depth); 785 } 786 exitstat |= altered; 787 } 788 789 /* 790 * Parse a line and determine its type. We keep the preprocessor line 791 * parser state between calls in the global variable linestate, with 792 * help from skipcomment(). 793 */ 794 static Linetype 795 parseline(void) 796 { 797 const char *cp; 798 struct macro *cursym; 799 Linetype retval; 800 Comment_state wascomment; 801 802 wascomment = incomment; 803 cp = skiphash(); 804 if (cp == NULL) 805 return (LT_EOF); 806 if (newline == NULL) { 807 if (strrchr(tline, '\n') == strrchr(tline, '\r') + 1) 808 newline = newline_crlf; 809 else 810 newline = newline_unix; 811 } 812 if (*cp == '\0') { 813 retval = LT_PLAIN; 814 goto done; 815 } 816 keyword = tline + (cp - tline); 817 if ((cp = matchsym("ifdef", keyword)) != NULL || 818 (cp = matchsym("ifndef", keyword)) != NULL) { 819 cp = skipcomment(cp); 820 if ((cursym = findsym(&cp)) == NULL) 821 retval = LT_IF; 822 else { 823 retval = (keyword[2] == 'n') 824 ? LT_FALSE : LT_TRUE; 825 if (cursym->value == NULL) 826 retval = (retval == LT_TRUE) 827 ? LT_FALSE : LT_TRUE; 828 if (cursym->ignore) 829 retval = (retval == LT_TRUE) 830 ? LT_TRUEI : LT_FALSEI; 831 } 832 } else if ((cp = matchsym("if", keyword)) != NULL) 833 retval = ifeval(&cp); 834 else if ((cp = matchsym("elif", keyword)) != NULL) 835 retval = linetype_if2elif(ifeval(&cp)); 836 else if ((cp = matchsym("else", keyword)) != NULL) 837 retval = LT_ELSE; 838 else if ((cp = matchsym("endif", keyword)) != NULL) 839 retval = LT_ENDIF; 840 else { 841 cp = skipsym(keyword); 842 /* no way can we deal with a continuation inside a keyword */ 843 if (strncmp(cp, "\\\r\n", 3) == 0 || 844 strncmp(cp, "\\\n", 2) == 0) 845 Eioccc(); 846 cp = skipline(cp); 847 retval = LT_PLAIN; 848 goto done; 849 } 850 cp = skipcomment(cp); 851 if (*cp != '\0') { 852 cp = skipline(cp); 853 if (retval == LT_TRUE || retval == LT_FALSE || 854 retval == LT_TRUEI || retval == LT_FALSEI) 855 retval = LT_IF; 856 if (retval == LT_ELTRUE || retval == LT_ELFALSE) 857 retval = LT_ELIF; 858 } 859 /* the following can happen if the last line of the file lacks a 860 newline or if there is too much whitespace in a directive */ 861 if (linestate == LS_HASH) { 862 long len = cp - tline; 863 if (fgets(tline + len, MAXLINE - len, input) == NULL) { 864 if (ferror(input)) 865 err(2, "can't read %s", filename); 866 debug("parser insert newline at EOF", linenum); 867 strcpy(tline + len, newline); 868 cp += strlen(newline); 869 linestate = LS_START; 870 } else { 871 debug("parser concatenate dangling whitespace"); 872 ++linenum; 873 cp = skipcomment(cp); 874 } 875 } 876 if (retval != LT_PLAIN && (wascomment || linestate != LS_START)) { 877 retval = linetype_2dodgy(retval); 878 linestate = LS_DIRTY; 879 } 880 done: 881 debug("parser line %d state %s comment %s line", linenum, 882 comment_name[incomment], linestate_name[linestate]); 883 return (retval); 884 } 885 886 /* 887 * These are the binary operators that are supported by the expression 888 * evaluator. 889 */ 890 static Linetype op_strict(long *p, long v, Linetype at, Linetype bt) { 891 if(at == LT_IF || bt == LT_IF) return (LT_IF); 892 return (*p = v, v ? LT_TRUE : LT_FALSE); 893 } 894 static Linetype op_lt(long *p, Linetype at, long a, Linetype bt, long b) { 895 return op_strict(p, a < b, at, bt); 896 } 897 static Linetype op_gt(long *p, Linetype at, long a, Linetype bt, long b) { 898 return op_strict(p, a > b, at, bt); 899 } 900 static Linetype op_le(long *p, Linetype at, long a, Linetype bt, long b) { 901 return op_strict(p, a <= b, at, bt); 902 } 903 static Linetype op_ge(long *p, Linetype at, long a, Linetype bt, long b) { 904 return op_strict(p, a >= b, at, bt); 905 } 906 static Linetype op_eq(long *p, Linetype at, long a, Linetype bt, long b) { 907 return op_strict(p, a == b, at, bt); 908 } 909 static Linetype op_ne(long *p, Linetype at, long a, Linetype bt, long b) { 910 return op_strict(p, a != b, at, bt); 911 } 912 static Linetype op_or(long *p, Linetype at, long a, Linetype bt, long b) { 913 if (!strictlogic && (at == LT_TRUE || bt == LT_TRUE)) 914 return (*p = 1, LT_TRUE); 915 return op_strict(p, a || b, at, bt); 916 } 917 static Linetype op_and(long *p, Linetype at, long a, Linetype bt, long b) { 918 if (!strictlogic && (at == LT_FALSE || bt == LT_FALSE)) 919 return (*p = 0, LT_FALSE); 920 return op_strict(p, a && b, at, bt); 921 } 922 static Linetype op_blsh(long *p, Linetype at, long a, Linetype bt, long b) { 923 return op_strict(p, a << b, at, bt); 924 } 925 static Linetype op_brsh(long *p, Linetype at, long a, Linetype bt, long b) { 926 return op_strict(p, a >> b, at, bt); 927 } 928 static Linetype op_add(long *p, Linetype at, long a, Linetype bt, long b) { 929 return op_strict(p, a + b, at, bt); 930 } 931 static Linetype op_sub(long *p, Linetype at, long a, Linetype bt, long b) { 932 return op_strict(p, a - b, at, bt); 933 } 934 static Linetype op_mul(long *p, Linetype at, long a, Linetype bt, long b) { 935 return op_strict(p, a * b, at, bt); 936 } 937 static Linetype op_div(long *p, Linetype at, long a, Linetype bt, long b) { 938 if (bt != LT_TRUE) { 939 debug("eval division by zero"); 940 return (LT_ERROR); 941 } 942 return op_strict(p, a / b, at, bt); 943 } 944 static Linetype op_mod(long *p, Linetype at, long a, Linetype bt, long b) { 945 return op_strict(p, a % b, at, bt); 946 } 947 static Linetype op_bor(long *p, Linetype at, long a, Linetype bt, long b) { 948 return op_strict(p, a | b, at, bt); 949 } 950 static Linetype op_bxor(long *p, Linetype at, long a, Linetype bt, long b) { 951 return op_strict(p, a ^ b, at, bt); 952 } 953 static Linetype op_band(long *p, Linetype at, long a, Linetype bt, long b) { 954 return op_strict(p, a & b, at, bt); 955 } 956 957 /* 958 * An evaluation function takes three arguments, as follows: (1) a pointer to 959 * an element of the precedence table which lists the operators at the current 960 * level of precedence; (2) a pointer to an integer which will receive the 961 * value of the expression; and (3) a pointer to a char* that points to the 962 * expression to be evaluated and that is updated to the end of the expression 963 * when evaluation is complete. The function returns LT_FALSE if the value of 964 * the expression is zero, LT_TRUE if it is non-zero, LT_IF if the expression 965 * depends on an unknown symbol, or LT_ERROR if there is a parse failure. 966 */ 967 struct ops; 968 969 typedef Linetype eval_fn(const struct ops *, long *, const char **); 970 971 static eval_fn eval_table, eval_unary; 972 973 /* 974 * The precedence table. Expressions involving binary operators are evaluated 975 * in a table-driven way by eval_table. When it evaluates a subexpression it 976 * calls the inner function with its first argument pointing to the next 977 * element of the table. Innermost expressions have special non-table-driven 978 * handling. 979 * 980 * The stop characters help with lexical analysis: an operator is not 981 * recognized if it is followed by one of the stop characters because 982 * that would make it a different operator. 983 */ 984 struct op { 985 const char *str; 986 Linetype (*fn)(long *, Linetype, long, Linetype, long); 987 const char *stop; 988 }; 989 struct ops { 990 eval_fn *inner; 991 struct op op[5]; 992 }; 993 static const struct ops eval_ops[] = { 994 { eval_table, { { "||", op_or, NULL } } }, 995 { eval_table, { { "&&", op_and, NULL } } }, 996 { eval_table, { { "|", op_bor, "|" } } }, 997 { eval_table, { { "^", op_bxor, NULL } } }, 998 { eval_table, { { "&", op_band, "&" } } }, 999 { eval_table, { { "==", op_eq, NULL }, 1000 { "!=", op_ne, NULL } } }, 1001 { eval_table, { { "<=", op_le, NULL }, 1002 { ">=", op_ge, NULL }, 1003 { "<", op_lt, "<=" }, 1004 { ">", op_gt, ">=" } } }, 1005 { eval_table, { { "<<", op_blsh, NULL }, 1006 { ">>", op_brsh, NULL } } }, 1007 { eval_table, { { "+", op_add, NULL }, 1008 { "-", op_sub, NULL } } }, 1009 { eval_unary, { { "*", op_mul, NULL }, 1010 { "/", op_div, NULL }, 1011 { "%", op_mod, NULL } } }, 1012 }; 1013 1014 /* Current operator precedence level */ 1015 static long prec(const struct ops *ops) 1016 { 1017 return (ops - eval_ops); 1018 } 1019 1020 /* 1021 * Function for evaluating the innermost parts of expressions, 1022 * viz. !expr (expr) number defined(symbol) symbol 1023 * We reset the constexpr flag in the last two cases. 1024 */ 1025 static Linetype 1026 eval_unary(const struct ops *ops, long *valp, const char **cpp) 1027 { 1028 const char *cp; 1029 char *ep; 1030 struct macro *sym; 1031 bool defparen; 1032 Linetype lt; 1033 1034 cp = skipcomment(*cpp); 1035 if (*cp == '!') { 1036 debug("eval%d !", prec(ops)); 1037 cp++; 1038 lt = eval_unary(ops, valp, &cp); 1039 if (lt == LT_ERROR) 1040 return (LT_ERROR); 1041 if (lt != LT_IF) { 1042 *valp = !*valp; 1043 lt = *valp ? LT_TRUE : LT_FALSE; 1044 } 1045 } else if (*cp == '~') { 1046 debug("eval%d ~", prec(ops)); 1047 cp++; 1048 lt = eval_unary(ops, valp, &cp); 1049 if (lt == LT_ERROR) 1050 return (LT_ERROR); 1051 if (lt != LT_IF) { 1052 *valp = ~(*valp); 1053 lt = *valp ? LT_TRUE : LT_FALSE; 1054 } 1055 } else if (*cp == '-') { 1056 debug("eval%d -", prec(ops)); 1057 cp++; 1058 lt = eval_unary(ops, valp, &cp); 1059 if (lt == LT_ERROR) 1060 return (LT_ERROR); 1061 if (lt != LT_IF) { 1062 *valp = -(*valp); 1063 lt = *valp ? LT_TRUE : LT_FALSE; 1064 } 1065 } else if (*cp == '(') { 1066 cp++; 1067 debug("eval%d (", prec(ops)); 1068 lt = eval_table(eval_ops, valp, &cp); 1069 if (lt == LT_ERROR) 1070 return (LT_ERROR); 1071 cp = skipcomment(cp); 1072 if (*cp++ != ')') 1073 return (LT_ERROR); 1074 } else if (isdigit((unsigned char)*cp)) { 1075 debug("eval%d number", prec(ops)); 1076 *valp = strtol(cp, &ep, 0); 1077 if (ep == cp) 1078 return (LT_ERROR); 1079 lt = *valp ? LT_TRUE : LT_FALSE; 1080 cp = ep; 1081 } else if (matchsym("defined", cp) != NULL) { 1082 cp = skipcomment(cp+7); 1083 if (*cp == '(') { 1084 cp = skipcomment(cp+1); 1085 defparen = true; 1086 } else { 1087 defparen = false; 1088 } 1089 sym = findsym(&cp); 1090 cp = skipcomment(cp); 1091 if (defparen && *cp++ != ')') { 1092 debug("eval%d defined missing ')'", prec(ops)); 1093 return (LT_ERROR); 1094 } 1095 if (sym == NULL) { 1096 debug("eval%d defined unknown", prec(ops)); 1097 lt = LT_IF; 1098 } else { 1099 debug("eval%d defined %s", prec(ops), sym->name); 1100 *valp = (sym->value != NULL); 1101 lt = *valp ? LT_TRUE : LT_FALSE; 1102 } 1103 constexpr = false; 1104 } else if (!endsym(*cp)) { 1105 debug("eval%d symbol", prec(ops)); 1106 sym = findsym(&cp); 1107 if (sym == NULL) { 1108 lt = LT_IF; 1109 cp = skipargs(cp); 1110 } else if (sym->value == NULL) { 1111 *valp = 0; 1112 lt = LT_FALSE; 1113 } else { 1114 *valp = strtol(sym->value, &ep, 0); 1115 if (*ep != '\0' || ep == sym->value) 1116 return (LT_ERROR); 1117 lt = *valp ? LT_TRUE : LT_FALSE; 1118 cp = skipargs(cp); 1119 } 1120 constexpr = false; 1121 } else { 1122 debug("eval%d bad expr", prec(ops)); 1123 return (LT_ERROR); 1124 } 1125 1126 *cpp = cp; 1127 debug("eval%d = %d", prec(ops), *valp); 1128 return (lt); 1129 } 1130 1131 /* 1132 * Table-driven evaluation of binary operators. 1133 */ 1134 static Linetype 1135 eval_table(const struct ops *ops, long *valp, const char **cpp) 1136 { 1137 const struct op *op; 1138 const char *cp; 1139 long val = 0; 1140 Linetype lt, rt; 1141 1142 debug("eval%d", prec(ops)); 1143 cp = *cpp; 1144 lt = ops->inner(ops+1, valp, &cp); 1145 if (lt == LT_ERROR) 1146 return (LT_ERROR); 1147 for (;;) { 1148 cp = skipcomment(cp); 1149 for (op = ops->op; op->str != NULL; op++) { 1150 if (strncmp(cp, op->str, strlen(op->str)) == 0) { 1151 /* assume only one-char operators have stop chars */ 1152 if (op->stop != NULL && cp[1] != '\0' && 1153 strchr(op->stop, cp[1]) != NULL) 1154 continue; 1155 else 1156 break; 1157 } 1158 } 1159 if (op->str == NULL) 1160 break; 1161 cp += strlen(op->str); 1162 debug("eval%d %s", prec(ops), op->str); 1163 rt = ops->inner(ops+1, &val, &cp); 1164 if (rt == LT_ERROR) 1165 return (LT_ERROR); 1166 lt = op->fn(valp, lt, *valp, rt, val); 1167 } 1168 1169 *cpp = cp; 1170 debug("eval%d = %d", prec(ops), *valp); 1171 debug("eval%d lt = %s", prec(ops), linetype_name[lt]); 1172 return (lt); 1173 } 1174 1175 /* 1176 * Evaluate the expression on a #if or #elif line. If we can work out 1177 * the result we return LT_TRUE or LT_FALSE accordingly, otherwise we 1178 * return just a generic LT_IF. 1179 */ 1180 static Linetype 1181 ifeval(const char **cpp) 1182 { 1183 Linetype ret; 1184 long val = 0; 1185 1186 debug("eval %s", *cpp); 1187 constexpr = killconsts ? false : true; 1188 ret = eval_table(eval_ops, &val, cpp); 1189 debug("eval = %d", val); 1190 return (constexpr ? LT_IF : ret == LT_ERROR ? LT_IF : ret); 1191 } 1192 1193 /* 1194 * Read a line and examine its initial part to determine if it is a 1195 * preprocessor directive. Returns NULL on EOF, or a pointer to a 1196 * preprocessor directive name, or a pointer to the zero byte at the 1197 * end of the line. 1198 */ 1199 static const char * 1200 skiphash(void) 1201 { 1202 const char *cp; 1203 1204 linenum++; 1205 if (fgets(tline, MAXLINE, input) == NULL) { 1206 if (ferror(input)) 1207 err(2, "can't read %s", filename); 1208 else 1209 return (NULL); 1210 } 1211 cp = skipcomment(tline); 1212 if (linestate == LS_START && *cp == '#') { 1213 linestate = LS_HASH; 1214 return (skipcomment(cp + 1)); 1215 } else if (*cp == '\0') { 1216 return (cp); 1217 } else { 1218 return (skipline(cp)); 1219 } 1220 } 1221 1222 /* 1223 * Mark a line dirty and consume the rest of it, keeping track of the 1224 * lexical state. 1225 */ 1226 static const char * 1227 skipline(const char *cp) 1228 { 1229 const char *pcp; 1230 if (*cp != '\0') 1231 linestate = LS_DIRTY; 1232 while (*cp != '\0') { 1233 cp = skipcomment(pcp = cp); 1234 if (pcp == cp) 1235 cp++; 1236 } 1237 return (cp); 1238 } 1239 1240 /* 1241 * Skip over comments, strings, and character literals and stop at the 1242 * next character position that is not whitespace. Between calls we keep 1243 * the comment state in the global variable incomment, and we also adjust 1244 * the global variable linestate when we see a newline. 1245 * XXX: doesn't cope with the buffer splitting inside a state transition. 1246 */ 1247 static const char * 1248 skipcomment(const char *cp) 1249 { 1250 if (text || ignoring[depth]) { 1251 for (; isspace((unsigned char)*cp); cp++) 1252 if (*cp == '\n') 1253 linestate = LS_START; 1254 return (cp); 1255 } 1256 while (*cp != '\0') 1257 /* don't reset to LS_START after a line continuation */ 1258 if (strncmp(cp, "\\\r\n", 3) == 0) 1259 cp += 3; 1260 else if (strncmp(cp, "\\\n", 2) == 0) 1261 cp += 2; 1262 else switch (incomment) { 1263 case NO_COMMENT: 1264 if (strncmp(cp, "/\\\r\n", 4) == 0) { 1265 incomment = STARTING_COMMENT; 1266 cp += 4; 1267 } else if (strncmp(cp, "/\\\n", 3) == 0) { 1268 incomment = STARTING_COMMENT; 1269 cp += 3; 1270 } else if (strncmp(cp, "/*", 2) == 0) { 1271 incomment = C_COMMENT; 1272 cp += 2; 1273 } else if (strncmp(cp, "//", 2) == 0) { 1274 incomment = CXX_COMMENT; 1275 cp += 2; 1276 } else if (strncmp(cp, "\'", 1) == 0) { 1277 incomment = CHAR_LITERAL; 1278 linestate = LS_DIRTY; 1279 cp += 1; 1280 } else if (strncmp(cp, "\"", 1) == 0) { 1281 incomment = STRING_LITERAL; 1282 linestate = LS_DIRTY; 1283 cp += 1; 1284 } else if (strncmp(cp, "R\"(", 3) == 0) { 1285 incomment = RAW_STRING_LITERAL; 1286 linestate = LS_DIRTY; 1287 cp += 3; 1288 } else if (strncmp(cp, "\n", 1) == 0) { 1289 linestate = LS_START; 1290 cp += 1; 1291 } else if (strchr(" \r\t", *cp) != NULL) { 1292 cp += 1; 1293 } else 1294 return (cp); 1295 continue; 1296 case CXX_COMMENT: 1297 if (strncmp(cp, "\n", 1) == 0) { 1298 incomment = NO_COMMENT; 1299 linestate = LS_START; 1300 } 1301 cp += 1; 1302 continue; 1303 case CHAR_LITERAL: 1304 case STRING_LITERAL: 1305 if ((incomment == CHAR_LITERAL && cp[0] == '\'') || 1306 (incomment == STRING_LITERAL && cp[0] == '\"')) { 1307 incomment = NO_COMMENT; 1308 cp += 1; 1309 } else if (cp[0] == '\\') { 1310 if (cp[1] == '\0') 1311 cp += 1; 1312 else 1313 cp += 2; 1314 } else if (strncmp(cp, "\n", 1) == 0) { 1315 if (incomment == CHAR_LITERAL) 1316 error("Unterminated char literal"); 1317 else 1318 error("Unterminated string literal"); 1319 } else 1320 cp += 1; 1321 continue; 1322 case RAW_STRING_LITERAL: 1323 if (strncmp(cp, ")\"", 2) == 0) { 1324 incomment = NO_COMMENT; 1325 cp += 2; 1326 } else 1327 cp += 1; 1328 continue; 1329 case C_COMMENT: 1330 if (strncmp(cp, "*\\\r\n", 4) == 0) { 1331 incomment = FINISHING_COMMENT; 1332 cp += 4; 1333 } else if (strncmp(cp, "*\\\n", 3) == 0) { 1334 incomment = FINISHING_COMMENT; 1335 cp += 3; 1336 } else if (strncmp(cp, "*/", 2) == 0) { 1337 incomment = NO_COMMENT; 1338 cp += 2; 1339 } else 1340 cp += 1; 1341 continue; 1342 case STARTING_COMMENT: 1343 if (*cp == '*') { 1344 incomment = C_COMMENT; 1345 cp += 1; 1346 } else if (*cp == '/') { 1347 incomment = CXX_COMMENT; 1348 cp += 1; 1349 } else { 1350 incomment = NO_COMMENT; 1351 linestate = LS_DIRTY; 1352 } 1353 continue; 1354 case FINISHING_COMMENT: 1355 if (*cp == '/') { 1356 incomment = NO_COMMENT; 1357 cp += 1; 1358 } else 1359 incomment = C_COMMENT; 1360 continue; 1361 default: 1362 abort(); /* bug */ 1363 } 1364 return (cp); 1365 } 1366 1367 /* 1368 * Skip macro arguments. 1369 */ 1370 static const char * 1371 skipargs(const char *cp) 1372 { 1373 const char *ocp = cp; 1374 int level = 0; 1375 cp = skipcomment(cp); 1376 if (*cp != '(') 1377 return (cp); 1378 do { 1379 if (*cp == '(') 1380 level++; 1381 if (*cp == ')') 1382 level--; 1383 cp = skipcomment(cp+1); 1384 } while (level != 0 && *cp != '\0'); 1385 if (level == 0) 1386 return (cp); 1387 else 1388 /* Rewind and re-detect the syntax error later. */ 1389 return (ocp); 1390 } 1391 1392 /* 1393 * Skip over an identifier. 1394 */ 1395 static const char * 1396 skipsym(const char *cp) 1397 { 1398 while (!endsym(*cp)) 1399 ++cp; 1400 return (cp); 1401 } 1402 1403 /* 1404 * Skip whitespace and take a copy of any following identifier. 1405 */ 1406 static const char * 1407 getsym(const char **cpp) 1408 { 1409 const char *cp = *cpp, *sym; 1410 1411 cp = skipcomment(cp); 1412 cp = skipsym(sym = cp); 1413 if (cp == sym) 1414 return NULL; 1415 *cpp = cp; 1416 return (xstrdup(sym, cp)); 1417 } 1418 1419 /* 1420 * Check that s (a symbol) matches the start of t, and that the 1421 * following character in t is not a symbol character. Returns a 1422 * pointer to the following character in t if there is a match, 1423 * otherwise NULL. 1424 */ 1425 static const char * 1426 matchsym(const char *s, const char *t) 1427 { 1428 while (*s != '\0' && *t != '\0') 1429 if (*s != *t) 1430 return (NULL); 1431 else 1432 ++s, ++t; 1433 if (*s == '\0' && endsym(*t)) 1434 return(t); 1435 else 1436 return(NULL); 1437 } 1438 1439 /* 1440 * Look for the symbol in the symbol table. If it is found, we return 1441 * the symbol table index, else we return -1. 1442 */ 1443 static struct macro * 1444 findsym(const char **strp) 1445 { 1446 const char *str; 1447 char *strkey; 1448 struct macro key, *res; 1449 1450 str = *strp; 1451 *strp = skipsym(str); 1452 if (symlist) { 1453 if (*strp == str) 1454 return (NULL); 1455 if (symdepth && firstsym) 1456 printf("%s%3d", zerosyms ? "" : "\n", depth); 1457 firstsym = zerosyms = false; 1458 printf("%s%.*s%s", 1459 symdepth ? " " : "", 1460 (int)(*strp-str), str, 1461 symdepth ? "" : "\n"); 1462 /* we don't care about the value of the symbol */ 1463 return (NULL); 1464 } 1465 1466 /* 1467 * 'str' just points into the current mid-parse input and is not 1468 * nul-terminated. We know the length of the symbol, *strp - str, but 1469 * need to provide a nul-terminated lookup key for RB_FIND's comparison 1470 * function. Create one here. 1471 */ 1472 strkey = malloc(*strp - str + 1); 1473 memcpy(strkey, str, *strp - str); 1474 strkey[*strp - str] = 0; 1475 1476 key.name = strkey; 1477 res = RB_FIND(MACROMAP, ¯o_tree, &key); 1478 if (res != NULL) 1479 debugsym("findsym", res); 1480 1481 free(strkey); 1482 return (res); 1483 } 1484 1485 /* 1486 * Resolve indirect symbol values to their final definitions. 1487 */ 1488 static void 1489 indirectsym(void) 1490 { 1491 const char *cp; 1492 int changed; 1493 struct macro *sym, *ind; 1494 1495 do { 1496 changed = 0; 1497 RB_FOREACH(sym, MACROMAP, ¯o_tree) { 1498 if (sym->value == NULL) 1499 continue; 1500 cp = sym->value; 1501 ind = findsym(&cp); 1502 if (ind == NULL || ind == sym || 1503 *cp != '\0' || 1504 ind->value == NULL || 1505 ind->value == sym->value) 1506 continue; 1507 debugsym("indir...", sym); 1508 sym->value = ind->value; 1509 debugsym("...ectsym", sym); 1510 changed++; 1511 } 1512 } while (changed); 1513 } 1514 1515 /* 1516 * Add a symbol to the symbol table, specified with the format sym=val 1517 */ 1518 static void 1519 addsym1(bool ignorethis, bool definethis, char *symval) 1520 { 1521 const char *sym, *val; 1522 1523 sym = symval; 1524 val = skipsym(sym); 1525 if (definethis && *val == '=') { 1526 symval[val - sym] = '\0'; 1527 val = val + 1; 1528 } else if (*val == '\0') { 1529 val = definethis ? "1" : NULL; 1530 } else { 1531 usage(); 1532 } 1533 addsym2(ignorethis, sym, val); 1534 } 1535 1536 /* 1537 * Add a symbol to the symbol table. 1538 */ 1539 static void 1540 addsym2(bool ignorethis, const char *symname, const char *val) 1541 { 1542 const char *cp = symname; 1543 struct macro *sym, *r; 1544 1545 sym = findsym(&cp); 1546 if (sym == NULL) { 1547 sym = calloc(1, sizeof(*sym)); 1548 sym->ignore = ignorethis; 1549 sym->name = symname; 1550 sym->value = val; 1551 r = RB_INSERT(MACROMAP, ¯o_tree, sym); 1552 assert(r == NULL); 1553 debugsym("addsym", sym); 1554 } else { 1555 sym->ignore = ignorethis; 1556 sym->value = val; 1557 debugsym("updsym", sym); 1558 } 1559 } 1560 1561 static void 1562 debugsym(const char *why, const struct macro *sym) 1563 { 1564 debug("%s %s%c%s", why, sym->name, 1565 sym->value ? '=' : ' ', 1566 sym->value ? sym->value : "undef"); 1567 } 1568 1569 /* 1570 * Add symbols to the symbol table from a file containing 1571 * #define and #undef preprocessor directives. 1572 */ 1573 static void 1574 defundefile(const char *fn) 1575 { 1576 filename = fn; 1577 input = fopen(fn, "rb"); 1578 if (input == NULL) 1579 err(2, "can't open %s", fn); 1580 linenum = 0; 1581 while (defundef()) 1582 ; 1583 if (ferror(input)) 1584 err(2, "can't read %s", filename); 1585 else 1586 fclose(input); 1587 if (incomment) 1588 error("EOF in comment"); 1589 } 1590 1591 /* 1592 * Read and process one #define or #undef directive 1593 */ 1594 static bool 1595 defundef(void) 1596 { 1597 const char *cp, *kw, *sym, *val, *end; 1598 1599 cp = skiphash(); 1600 if (cp == NULL) 1601 return (false); 1602 if (*cp == '\0') 1603 goto done; 1604 /* strip trailing whitespace, and do a fairly rough check to 1605 avoid unsupported multi-line preprocessor directives */ 1606 end = cp + strlen(cp); 1607 while (end > tline && strchr(" \t\n\r", end[-1]) != NULL) 1608 --end; 1609 if (end > tline && end[-1] == '\\') 1610 Eioccc(); 1611 1612 kw = cp; 1613 if ((cp = matchsym("define", kw)) != NULL) { 1614 sym = getsym(&cp); 1615 if (sym == NULL) 1616 error("Missing macro name in #define"); 1617 if (*cp == '(') { 1618 val = "1"; 1619 } else { 1620 cp = skipcomment(cp); 1621 val = (cp < end) ? xstrdup(cp, end) : ""; 1622 } 1623 debug("#define"); 1624 addsym2(false, sym, val); 1625 } else if ((cp = matchsym("undef", kw)) != NULL) { 1626 sym = getsym(&cp); 1627 if (sym == NULL) 1628 error("Missing macro name in #undef"); 1629 cp = skipcomment(cp); 1630 debug("#undef"); 1631 addsym2(false, sym, NULL); 1632 } else { 1633 error("Unrecognized preprocessor directive"); 1634 } 1635 skipline(cp); 1636 done: 1637 debug("parser line %d state %s comment %s line", linenum, 1638 comment_name[incomment], linestate_name[linestate]); 1639 return (true); 1640 } 1641 1642 /* 1643 * Concatenate two strings into new memory, checking for failure. 1644 */ 1645 static char * 1646 astrcat(const char *s1, const char *s2) 1647 { 1648 char *s; 1649 int len; 1650 size_t size; 1651 1652 len = snprintf(NULL, 0, "%s%s", s1, s2); 1653 if (len < 0) 1654 err(2, "snprintf"); 1655 size = (size_t)len + 1; 1656 s = (char *)malloc(size); 1657 if (s == NULL) 1658 err(2, "malloc"); 1659 snprintf(s, size, "%s%s", s1, s2); 1660 return (s); 1661 } 1662 1663 /* 1664 * Duplicate a segment of a string, checking for failure. 1665 */ 1666 static const char * 1667 xstrdup(const char *start, const char *end) 1668 { 1669 size_t n; 1670 char *s; 1671 1672 if (end < start) abort(); /* bug */ 1673 n = (size_t)(end - start) + 1; 1674 s = (char *)malloc(n); 1675 if (s == NULL) 1676 err(2, "malloc"); 1677 snprintf(s, n, "%s", start); 1678 return (s); 1679 } 1680 1681 /* 1682 * Diagnostics. 1683 */ 1684 static void 1685 debug(const char *msg, ...) 1686 { 1687 va_list ap; 1688 1689 if (debugging) { 1690 va_start(ap, msg); 1691 vwarnx(msg, ap); 1692 va_end(ap); 1693 } 1694 } 1695 1696 static void 1697 error(const char *msg) 1698 { 1699 if (depth == 0) 1700 warnx("%s: %d: %s", filename, linenum, msg); 1701 else 1702 warnx("%s: %d: %s (#if line %d depth %d)", 1703 filename, linenum, msg, stifline[depth], depth); 1704 closeio(); 1705 errx(2, "Output may be truncated"); 1706 } 1707