Eric Andersen | aa0765e | 1999-10-22 04:30:20 +0000 | [diff] [blame] | 1 | /* regexp.c */ |
| 2 | |
| 3 | #include "internal.h" |
| 4 | #include "regexp.h" |
| 5 | #include <setjmp.h> |
| 6 | #include <stdio.h> |
| 7 | #include <ctype.h> |
| 8 | |
| 9 | |
Eric Andersen | 7f1acfd | 1999-10-29 23:09:13 +0000 | [diff] [blame] | 10 | #if ( defined BB_GREP || defined BB_FIND || defined BB_SED) |
Eric Andersen | aa0765e | 1999-10-22 04:30:20 +0000 | [diff] [blame] | 11 | |
| 12 | /* This also tries to find a needle in a haystack, but uses |
| 13 | * real regular expressions.... The fake regular expression |
| 14 | * version of find_match lives in utility.c. Using this version |
| 15 | * will add 3.9k to busybox... |
| 16 | * -Erik Andersen |
| 17 | */ |
| 18 | extern int find_match(char *haystack, char *needle, int ignoreCase) |
| 19 | { |
| 20 | int status; |
| 21 | struct regexp* re; |
| 22 | re = regcomp( needle); |
| 23 | status = regexec(re, haystack, FALSE, ignoreCase); |
| 24 | free( re); |
| 25 | return( status); |
| 26 | } |
| 27 | |
Eric Andersen | 7f1acfd | 1999-10-29 23:09:13 +0000 | [diff] [blame] | 28 | #if defined BB_SED |
Eric Andersen | c1525e8 | 1999-10-29 00:07:31 +0000 | [diff] [blame] | 29 | /* This performs substitutions after a regexp match has been found. |
| 30 | * The new string is returned. It is malloc'ed, and do must be freed. */ |
Eric Andersen | 7f1acfd | 1999-10-29 23:09:13 +0000 | [diff] [blame] | 31 | extern int replace_match(char *haystack, char *needle, char *newNeedle, int ignoreCase) |
Eric Andersen | c1525e8 | 1999-10-29 00:07:31 +0000 | [diff] [blame] | 32 | { |
| 33 | int status; |
Eric Andersen | c1525e8 | 1999-10-29 00:07:31 +0000 | [diff] [blame] | 34 | struct regexp* re; |
Eric Andersen | 7f1acfd | 1999-10-29 23:09:13 +0000 | [diff] [blame] | 35 | char *s, buf[BUF_SIZE], *d = buf; |
| 36 | |
Eric Andersen | c1525e8 | 1999-10-29 00:07:31 +0000 | [diff] [blame] | 37 | re = regcomp( needle); |
| 38 | status = regexec(re, haystack, FALSE, ignoreCase); |
Eric Andersen | 7f1acfd | 1999-10-29 23:09:13 +0000 | [diff] [blame] | 39 | if (status==TRUE) { |
| 40 | s=haystack; |
Eric Andersen | c1525e8 | 1999-10-29 00:07:31 +0000 | [diff] [blame] | 41 | |
Eric Andersen | 7f1acfd | 1999-10-29 23:09:13 +0000 | [diff] [blame] | 42 | do { |
| 43 | /* copy stuff from before the match */ |
| 44 | while (s < re->startp[0]) |
| 45 | *d++ = *s++; |
| 46 | /* substitute for the matched part */ |
| 47 | regsub(re, newNeedle, d); |
| 48 | s = re->endp[0]; |
| 49 | d += strlen(d); |
| 50 | } while (regexec(re, s, FALSE, ignoreCase) == TRUE); |
| 51 | /* copy stuff from after the match */ |
| 52 | while ( (*d++ = *s++) ) {} |
| 53 | d[-1] = '\n'; |
| 54 | d[0] = '\0'; |
| 55 | strcpy(haystack, buf); |
| 56 | } |
Eric Andersen | c1525e8 | 1999-10-29 00:07:31 +0000 | [diff] [blame] | 57 | free( re); |
| 58 | return( status); |
| 59 | } |
Eric Andersen | 7f1acfd | 1999-10-29 23:09:13 +0000 | [diff] [blame] | 60 | #endif |
Eric Andersen | c1525e8 | 1999-10-29 00:07:31 +0000 | [diff] [blame] | 61 | |
Eric Andersen | aa0765e | 1999-10-22 04:30:20 +0000 | [diff] [blame] | 62 | |
| 63 | /* code swiped from elvis-tiny 1.4 (a clone of vi) and adjusted to |
| 64 | * suit the needs of busybox by Erik Andersen. |
| 65 | * |
| 66 | * From the README: |
| 67 | * "Elvis is freely redistributable, in either source form or executable form. |
| 68 | * There are no restrictions on how you may use it". |
| 69 | * Elvis was written by Steve Kirkendall <kirkenda@cs.pdx.edu> |
| 70 | * |
| 71 | * |
| 72 | * This file contains the code that compiles regular expressions and executes |
| 73 | * them. It supports the same syntax and features as vi's regular expression |
| 74 | * code. Specifically, the meta characters are: |
| 75 | * ^ matches the beginning of a line |
| 76 | * $ matches the end of a line |
| 77 | * \< matches the beginning of a word |
| 78 | * \> matches the end of a word |
| 79 | * . matches any single character |
| 80 | * [] matches any character in a character class |
| 81 | * \( delimits the start of a subexpression |
| 82 | * \) delimits the end of a subexpression |
| 83 | * * repeats the preceding 0 or more times |
| 84 | * NOTE: You cannot follow a \) with a *. |
| 85 | * |
| 86 | * The physical structure of a compiled RE is as follows: |
| 87 | * - First, there is a one-byte value that says how many character classes |
| 88 | * are used in this regular expression |
| 89 | * - Next, each character class is stored as a bitmap that is 256 bits |
| 90 | * (32 bytes) long. |
| 91 | * - A mixture of literal characters and compiled meta characters follows. |
| 92 | * This begins with M_BEGIN(0) and ends with M_END(0). All meta chars |
| 93 | * are stored as a \n followed by a one-byte code, so they take up two |
| 94 | * bytes apiece. Literal characters take up one byte apiece. \n can't |
| 95 | * be used as a literal character. |
| 96 | * |
| 97 | */ |
| 98 | |
| 99 | |
| 100 | |
| 101 | static char *previous; /* the previous regexp, used when null regexp is given */ |
| 102 | static char *previous1; /* a copy of the text from the previous substitution for regsub()*/ |
| 103 | |
| 104 | |
| 105 | /* These are used to classify or recognize meta-characters */ |
| 106 | #define META '\0' |
| 107 | #define BASE_META(m) ((m) - 256) |
| 108 | #define INT_META(c) ((c) + 256) |
| 109 | #define IS_META(m) ((m) >= 256) |
| 110 | #define IS_CLASS(m) ((m) >= M_CLASS(0) && (m) <= M_CLASS(9)) |
| 111 | #define IS_START(m) ((m) >= M_START(0) && (m) <= M_START(9)) |
| 112 | #define IS_END(m) ((m) >= M_END(0) && (m) <= M_END(9)) |
| 113 | #define IS_CLOSURE(m) ((m) >= M_SPLAT && (m) <= M_QMARK) |
| 114 | #define ADD_META(s,m) (*(s)++ = META, *(s)++ = BASE_META(m)) |
| 115 | #define GET_META(s) (*(s) == META ? INT_META(*++(s)) : *s) |
| 116 | |
| 117 | /* These are the internal codes used for each type of meta-character */ |
| 118 | #define M_BEGLINE 256 /* internal code for ^ */ |
| 119 | #define M_ENDLINE 257 /* internal code for $ */ |
| 120 | #define M_BEGWORD 258 /* internal code for \< */ |
| 121 | #define M_ENDWORD 259 /* internal code for \> */ |
| 122 | #define M_ANY 260 /* internal code for . */ |
| 123 | #define M_SPLAT 261 /* internal code for * */ |
| 124 | #define M_PLUS 262 /* internal code for \+ */ |
| 125 | #define M_QMARK 263 /* internal code for \? */ |
| 126 | #define M_CLASS(n) (264+(n)) /* internal code for [] */ |
| 127 | #define M_START(n) (274+(n)) /* internal code for \( */ |
| 128 | #define M_END(n) (284+(n)) /* internal code for \) */ |
| 129 | |
| 130 | /* These are used during compilation */ |
| 131 | static int class_cnt; /* used to assign class IDs */ |
| 132 | static int start_cnt; /* used to assign start IDs */ |
| 133 | static int end_stk[NSUBEXP];/* used to assign end IDs */ |
| 134 | static int end_sp; |
| 135 | static char *retext; /* points to the text being compiled */ |
| 136 | |
| 137 | /* error-handling stuff */ |
| 138 | jmp_buf errorhandler; |
| 139 | #define FAIL(why) fprintf(stderr, why); longjmp(errorhandler, 1) |
| 140 | |
| 141 | |
| 142 | |
| 143 | |
| 144 | /* This function builds a bitmap for a particular class */ |
| 145 | /* text -- start of the class */ |
| 146 | /* bmap -- the bitmap */ |
| 147 | static char *makeclass(char* text, char* bmap) |
| 148 | { |
| 149 | int i; |
| 150 | int complement = 0; |
| 151 | |
| 152 | |
| 153 | /* zero the bitmap */ |
| 154 | for (i = 0; bmap && i < 32; i++) |
| 155 | { |
| 156 | bmap[i] = 0; |
| 157 | } |
| 158 | |
| 159 | /* see if we're going to complement this class */ |
| 160 | if (*text == '^') |
| 161 | { |
| 162 | text++; |
| 163 | complement = 1; |
| 164 | } |
| 165 | |
| 166 | /* add in the characters */ |
| 167 | while (*text && *text != ']') |
| 168 | { |
| 169 | /* is this a span of characters? */ |
| 170 | if (text[1] == '-' && text[2]) |
| 171 | { |
| 172 | /* spans can't be backwards */ |
| 173 | if (text[0] > text[2]) |
| 174 | { |
| 175 | FAIL("Backwards span in []"); |
| 176 | } |
| 177 | |
| 178 | /* add each character in the span to the bitmap */ |
| 179 | for (i = text[0]; bmap && i <= text[2]; i++) |
| 180 | { |
| 181 | bmap[i >> 3] |= (1 << (i & 7)); |
| 182 | } |
| 183 | |
| 184 | /* move past this span */ |
| 185 | text += 3; |
| 186 | } |
| 187 | else |
| 188 | { |
| 189 | /* add this single character to the span */ |
| 190 | i = *text++; |
| 191 | if (bmap) |
| 192 | { |
| 193 | bmap[i >> 3] |= (1 << (i & 7)); |
| 194 | } |
| 195 | } |
| 196 | } |
| 197 | |
| 198 | /* make sure the closing ] is missing */ |
| 199 | if (*text++ != ']') |
| 200 | { |
| 201 | FAIL("] missing"); |
| 202 | } |
| 203 | |
| 204 | /* if we're supposed to complement this class, then do so */ |
| 205 | if (complement && bmap) |
| 206 | { |
| 207 | for (i = 0; i < 32; i++) |
| 208 | { |
| 209 | bmap[i] = ~bmap[i]; |
| 210 | } |
| 211 | } |
| 212 | |
| 213 | return text; |
| 214 | } |
| 215 | |
| 216 | |
| 217 | |
| 218 | |
| 219 | /* This function gets the next character or meta character from a string. |
| 220 | * The pointer is incremented by 1, or by 2 for \-quoted characters. For [], |
| 221 | * a bitmap is generated via makeclass() (if re is given), and the |
| 222 | * character-class text is skipped. |
| 223 | */ |
| 224 | static int gettoken(sptr, re) |
| 225 | char **sptr; |
| 226 | regexp *re; |
| 227 | { |
| 228 | int c; |
| 229 | |
| 230 | c = **sptr; |
| 231 | ++*sptr; |
| 232 | if (c == '\\') |
| 233 | { |
| 234 | c = **sptr; |
| 235 | ++*sptr; |
| 236 | switch (c) |
| 237 | { |
| 238 | case '<': |
| 239 | return M_BEGWORD; |
| 240 | |
| 241 | case '>': |
| 242 | return M_ENDWORD; |
| 243 | |
| 244 | case '(': |
| 245 | if (start_cnt >= NSUBEXP) |
| 246 | { |
| 247 | FAIL("Too many \\(s"); |
| 248 | } |
| 249 | end_stk[end_sp++] = start_cnt; |
| 250 | return M_START(start_cnt++); |
| 251 | |
| 252 | case ')': |
| 253 | if (end_sp <= 0) |
| 254 | { |
| 255 | FAIL("Mismatched \\)"); |
| 256 | } |
| 257 | return M_END(end_stk[--end_sp]); |
| 258 | |
| 259 | case '*': |
| 260 | return M_SPLAT; |
| 261 | |
| 262 | case '.': |
| 263 | return M_ANY; |
| 264 | |
| 265 | case '+': |
| 266 | return M_PLUS; |
| 267 | |
| 268 | case '?': |
| 269 | return M_QMARK; |
| 270 | |
| 271 | default: |
| 272 | return c; |
| 273 | } |
| 274 | } |
| 275 | else { |
| 276 | switch (c) |
| 277 | { |
| 278 | case '^': |
| 279 | if (*sptr == retext + 1) |
| 280 | { |
| 281 | return M_BEGLINE; |
| 282 | } |
| 283 | return c; |
| 284 | |
| 285 | case '$': |
| 286 | if (!**sptr) |
| 287 | { |
| 288 | return M_ENDLINE; |
| 289 | } |
| 290 | return c; |
| 291 | |
| 292 | case '.': |
| 293 | return M_ANY; |
| 294 | |
| 295 | case '*': |
| 296 | return M_SPLAT; |
| 297 | |
| 298 | case '[': |
| 299 | /* make sure we don't have too many classes */ |
| 300 | if (class_cnt >= 10) |
| 301 | { |
| 302 | FAIL("Too many []s"); |
| 303 | } |
| 304 | |
| 305 | /* process the character list for this class */ |
| 306 | if (re) |
| 307 | { |
| 308 | /* generate the bitmap for this class */ |
| 309 | *sptr = makeclass(*sptr, re->program + 1 + 32 * class_cnt); |
| 310 | } |
| 311 | else |
| 312 | { |
| 313 | /* skip to end of the class */ |
| 314 | *sptr = makeclass(*sptr, (char *)0); |
| 315 | } |
| 316 | return M_CLASS(class_cnt++); |
| 317 | |
| 318 | default: |
| 319 | return c; |
| 320 | } |
| 321 | } |
| 322 | /*NOTREACHED*/ |
| 323 | } |
| 324 | |
| 325 | |
| 326 | |
| 327 | |
| 328 | /* This function calculates the number of bytes that will be needed for a |
| 329 | * compiled RE. Its argument is the uncompiled version. It is not clever |
| 330 | * about catching syntax errors; that is done in a later pass. |
| 331 | */ |
| 332 | static unsigned calcsize(text) |
| 333 | char *text; |
| 334 | { |
| 335 | unsigned size; |
| 336 | int token; |
| 337 | |
| 338 | retext = text; |
| 339 | class_cnt = 0; |
| 340 | start_cnt = 1; |
| 341 | end_sp = 0; |
| 342 | size = 5; |
| 343 | while ((token = gettoken(&text, (regexp *)0)) != 0) |
| 344 | { |
| 345 | if (IS_CLASS(token)) |
| 346 | { |
| 347 | size += 34; |
| 348 | } |
| 349 | else if (IS_META(token)) |
| 350 | { |
| 351 | size += 2; |
| 352 | } |
| 353 | else |
| 354 | { |
| 355 | size++; |
| 356 | } |
| 357 | } |
| 358 | |
| 359 | return size; |
| 360 | } |
| 361 | |
| 362 | |
| 363 | |
| 364 | /*---------------------------------------------------------------------------*/ |
| 365 | |
| 366 | |
| 367 | /* This function checks for a match between a character and a token which is |
| 368 | * known to represent a single character. It returns 0 if they match, or |
| 369 | * 1 if they don't. |
| 370 | */ |
| 371 | static int match1(regexp* re, char ch, int token, int ignoreCase) |
| 372 | { |
| 373 | if (!ch) |
| 374 | { |
| 375 | /* the end of a line can't match any RE of width 1 */ |
| 376 | return 1; |
| 377 | } |
| 378 | if (token == M_ANY) |
| 379 | { |
| 380 | return 0; |
| 381 | } |
| 382 | else if (IS_CLASS(token)) |
| 383 | { |
| 384 | if (re->program[1 + 32 * (token - M_CLASS(0)) + (ch >> 3)] & (1 << (ch & 7))) |
| 385 | return 0; |
| 386 | } |
| 387 | else if (ch == token |
| 388 | || (ignoreCase==TRUE && isupper(ch) && tolower(ch) == token)) |
| 389 | { |
| 390 | return 0; |
| 391 | } |
| 392 | return 1; |
| 393 | } |
| 394 | |
| 395 | |
| 396 | |
| 397 | /* This function checks characters up to and including the next closure, at |
| 398 | * which point it does a recursive call to check the rest of it. This function |
| 399 | * returns 0 if everything matches, or 1 if something doesn't match. |
| 400 | */ |
| 401 | /* re -- the regular expression */ |
| 402 | /* str -- the string */ |
| 403 | /* prog -- a portion of re->program, an compiled RE */ |
| 404 | /* here -- a portion of str, the string to compare it to */ |
| 405 | static int match(regexp* re, char* str, char* prog, char* here, int ignoreCase) |
| 406 | { |
| 407 | int token; |
| 408 | int nmatched; |
| 409 | int closure; |
| 410 | |
| 411 | for (token = GET_META(prog); !IS_CLOSURE(token); prog++, token = GET_META(prog)) |
| 412 | { |
| 413 | switch (token) |
| 414 | { |
| 415 | /*case M_BEGLINE: can't happen; re->bol is used instead */ |
| 416 | case M_ENDLINE: |
| 417 | if (*here) |
| 418 | return 1; |
| 419 | break; |
| 420 | |
| 421 | case M_BEGWORD: |
| 422 | if (here != str && |
| 423 | (here[-1] == '_' || |
| 424 | (isascii(here[-1]) && isalnum(here[-1])))) |
| 425 | return 1; |
| 426 | break; |
| 427 | |
| 428 | case M_ENDWORD: |
| 429 | if ((here[0] == '_' || isascii(here[0])) && isalnum(here[0])) |
| 430 | return 1; |
| 431 | break; |
| 432 | |
| 433 | case M_START(0): |
| 434 | case M_START(1): |
| 435 | case M_START(2): |
| 436 | case M_START(3): |
| 437 | case M_START(4): |
| 438 | case M_START(5): |
| 439 | case M_START(6): |
| 440 | case M_START(7): |
| 441 | case M_START(8): |
| 442 | case M_START(9): |
| 443 | re->startp[token - M_START(0)] = (char *)here; |
| 444 | break; |
| 445 | |
| 446 | case M_END(0): |
| 447 | case M_END(1): |
| 448 | case M_END(2): |
| 449 | case M_END(3): |
| 450 | case M_END(4): |
| 451 | case M_END(5): |
| 452 | case M_END(6): |
| 453 | case M_END(7): |
| 454 | case M_END(8): |
| 455 | case M_END(9): |
| 456 | re->endp[token - M_END(0)] = (char *)here; |
| 457 | if (token == M_END(0)) |
| 458 | { |
| 459 | return 0; |
| 460 | } |
| 461 | break; |
| 462 | |
| 463 | default: /* literal, M_CLASS(n), or M_ANY */ |
| 464 | if (match1(re, *here, token, ignoreCase) != 0) |
| 465 | return 1; |
| 466 | here++; |
| 467 | } |
| 468 | } |
| 469 | |
| 470 | /* C L O S U R E */ |
| 471 | |
| 472 | /* step 1: see what we have to match against, and move "prog" to point |
| 473 | * the the remainder of the compiled RE. |
| 474 | */ |
| 475 | closure = token; |
| 476 | prog++, token = GET_META(prog); |
| 477 | prog++; |
| 478 | |
| 479 | /* step 2: see how many times we can match that token against the string */ |
| 480 | for (nmatched = 0; |
| 481 | (closure != M_QMARK || nmatched < 1) && *here && match1(re, *here, token, ignoreCase) == 0; |
| 482 | nmatched++, here++) |
| 483 | { |
| 484 | } |
| 485 | |
| 486 | /* step 3: try to match the remainder, and back off if it doesn't */ |
| 487 | while (nmatched >= 0 && match(re, str, prog, here, ignoreCase) != 0) |
| 488 | { |
| 489 | nmatched--; |
| 490 | here--; |
| 491 | } |
| 492 | |
| 493 | /* so how did it work out? */ |
| 494 | if (nmatched >= ((closure == M_PLUS) ? 1 : 0)) |
| 495 | return 0; |
| 496 | return 1; |
| 497 | } |
| 498 | |
| 499 | |
| 500 | /* This function compiles a regexp. */ |
| 501 | extern regexp *regcomp(char* text) |
| 502 | { |
| 503 | int needfirst; |
| 504 | unsigned size; |
| 505 | int token; |
| 506 | int peek; |
| 507 | char *build; |
| 508 | regexp *re; |
| 509 | |
| 510 | |
| 511 | /* prepare for error handling */ |
| 512 | re = (regexp *)0; |
| 513 | if (setjmp(errorhandler)) |
| 514 | { |
| 515 | if (re) |
| 516 | { |
| 517 | free(re); |
| 518 | } |
| 519 | return (regexp *)0; |
| 520 | } |
| 521 | |
| 522 | /* if an empty regexp string was given, use the previous one */ |
| 523 | if (*text == 0) |
| 524 | { |
| 525 | if (!previous) |
| 526 | { |
| 527 | FAIL("No previous RE"); |
| 528 | } |
| 529 | text = previous; |
| 530 | } |
| 531 | else /* non-empty regexp given, so remember it */ |
| 532 | { |
| 533 | if (previous) |
| 534 | free(previous); |
| 535 | previous = (char *)malloc((unsigned)(strlen(text) + 1)); |
| 536 | if (previous) |
| 537 | strcpy(previous, text); |
| 538 | } |
| 539 | |
| 540 | /* allocate memory */ |
| 541 | class_cnt = 0; |
| 542 | start_cnt = 1; |
| 543 | end_sp = 0; |
| 544 | retext = text; |
| 545 | size = calcsize(text) + sizeof(regexp); |
| 546 | re = (regexp *)malloc((unsigned)size); |
| 547 | |
| 548 | if (!re) |
| 549 | { |
| 550 | FAIL("Not enough memory for this RE"); |
| 551 | } |
| 552 | |
| 553 | /* compile it */ |
| 554 | build = &re->program[1 + 32 * class_cnt]; |
| 555 | re->program[0] = class_cnt; |
| 556 | for (token = 0; token < NSUBEXP; token++) |
| 557 | { |
| 558 | re->startp[token] = re->endp[token] = (char *)0; |
| 559 | } |
| 560 | re->first = 0; |
| 561 | re->bol = 0; |
| 562 | re->minlen = 0; |
| 563 | needfirst = 1; |
| 564 | class_cnt = 0; |
| 565 | start_cnt = 1; |
| 566 | end_sp = 0; |
| 567 | retext = text; |
| 568 | for (token = M_START(0), peek = gettoken(&text, re); |
| 569 | token; |
| 570 | token = peek, peek = gettoken(&text, re)) |
| 571 | { |
| 572 | /* special processing for the closure operator */ |
| 573 | if (IS_CLOSURE(peek)) |
| 574 | { |
| 575 | /* detect misuse of closure operator */ |
| 576 | if (IS_START(token)) |
| 577 | { |
| 578 | FAIL("* or \\+ or \\? follows nothing"); |
| 579 | } |
| 580 | else if (IS_META(token) && token != M_ANY && !IS_CLASS(token)) |
| 581 | { |
| 582 | FAIL("* or \\+ or \\? can only follow a normal character or . or []"); |
| 583 | } |
| 584 | |
| 585 | /* it is okay -- make it prefix instead of postfix */ |
| 586 | ADD_META(build, peek); |
| 587 | |
| 588 | /* take care of "needfirst" - is this the first char? */ |
| 589 | if (needfirst && peek == M_PLUS && !IS_META(token)) |
| 590 | { |
| 591 | re->first = token; |
| 592 | } |
| 593 | needfirst = 0; |
| 594 | |
| 595 | /* we used "peek" -- need to refill it */ |
| 596 | peek = gettoken(&text, re); |
| 597 | if (IS_CLOSURE(peek)) |
| 598 | { |
| 599 | FAIL("* or \\+ or \\? doubled up"); |
| 600 | } |
| 601 | } |
| 602 | else if (!IS_META(token)) |
| 603 | { |
| 604 | /* normal char is NOT argument of closure */ |
| 605 | if (needfirst) |
| 606 | { |
| 607 | re->first = token; |
| 608 | needfirst = 0; |
| 609 | } |
| 610 | re->minlen++; |
| 611 | } |
| 612 | else if (token == M_ANY || IS_CLASS(token)) |
| 613 | { |
| 614 | /* . or [] is NOT argument of closure */ |
| 615 | needfirst = 0; |
| 616 | re->minlen++; |
| 617 | } |
| 618 | |
| 619 | /* the "token" character is not closure -- process it normally */ |
| 620 | if (token == M_BEGLINE) |
| 621 | { |
| 622 | /* set the BOL flag instead of storing M_BEGLINE */ |
| 623 | re->bol = 1; |
| 624 | } |
| 625 | else if (IS_META(token)) |
| 626 | { |
| 627 | ADD_META(build, token); |
| 628 | } |
| 629 | else |
| 630 | { |
| 631 | *build++ = token; |
| 632 | } |
| 633 | } |
| 634 | |
| 635 | /* end it with a \) which MUST MATCH the opening \( */ |
| 636 | ADD_META(build, M_END(0)); |
| 637 | if (end_sp > 0) |
| 638 | { |
| 639 | FAIL("Not enough \\)s"); |
| 640 | } |
| 641 | |
| 642 | return re; |
| 643 | } |
| 644 | |
| 645 | |
| 646 | |
| 647 | |
| 648 | /* This function searches through a string for text that matches an RE. */ |
| 649 | /* re -- the compiled regexp to search for */ |
| 650 | /* str -- the string to search through */ |
| 651 | /* bol -- does str start at the beginning of a line? (boolean) */ |
| 652 | /* ignoreCase -- ignoreCase or not */ |
| 653 | extern int regexec(struct regexp* re, char* str, int bol, int ignoreCase) |
| 654 | { |
| 655 | char *prog; /* the entry point of re->program */ |
| 656 | int len; /* length of the string */ |
| 657 | char *here; |
| 658 | |
| 659 | /* if must start at the beginning of a line, and this isn't, then fail */ |
| 660 | if (re->bol && bol==TRUE) |
| 661 | { |
| 662 | return FALSE; |
| 663 | } |
| 664 | |
| 665 | len = strlen(str); |
| 666 | prog = re->program + 1 + 32 * re->program[0]; |
| 667 | |
| 668 | /* search for the RE in the string */ |
| 669 | if (re->bol) |
| 670 | { |
| 671 | /* must occur at BOL */ |
| 672 | if ((re->first |
| 673 | && match1(re, *(char *)str, re->first, ignoreCase))/* wrong first letter? */ |
| 674 | || len < re->minlen /* not long enough? */ |
| 675 | || match(re, (char *)str, prog, str, ignoreCase)) /* doesn't match? */ |
| 676 | return FALSE; /* THEN FAIL! */ |
| 677 | } |
| 678 | else if (ignoreCase == FALSE) |
| 679 | { |
| 680 | /* can occur anywhere in the line, noignorecase */ |
| 681 | for (here = (char *)str; |
| 682 | (re->first && re->first != *here) |
| 683 | || match(re, (char *)str, prog, here, ignoreCase); |
| 684 | here++, len--) |
| 685 | { |
| 686 | if (len < re->minlen) |
| 687 | return FALSE; |
| 688 | } |
| 689 | } |
| 690 | else |
| 691 | { |
| 692 | /* can occur anywhere in the line, ignorecase */ |
| 693 | for (here = (char *)str; |
| 694 | (re->first && match1(re, *here, (int)re->first, ignoreCase)) |
| 695 | || match(re, (char *)str, prog, here, ignoreCase); |
| 696 | here++, len--) |
| 697 | { |
| 698 | if (len < re->minlen) |
| 699 | return FALSE; |
| 700 | } |
| 701 | } |
| 702 | |
| 703 | /* if we didn't fail, then we must have succeeded */ |
| 704 | return TRUE; |
| 705 | } |
| 706 | |
| 707 | |
| 708 | |
| 709 | |
Eric Andersen | 7f1acfd | 1999-10-29 23:09:13 +0000 | [diff] [blame] | 710 | #if defined BB_SED |
Eric Andersen | aa0765e | 1999-10-22 04:30:20 +0000 | [diff] [blame] | 711 | /* This performs substitutions after a regexp match has been found. */ |
| 712 | extern void regsub(regexp* re, char* src, char* dst) |
| 713 | { |
| 714 | char *cpy; |
| 715 | char *end; |
| 716 | char c; |
| 717 | char *start; |
| 718 | int mod; |
| 719 | |
| 720 | mod = 0; |
| 721 | |
| 722 | start = src; |
| 723 | while ((c = *src++) != '\0') |
| 724 | { |
| 725 | /* recognize any meta characters */ |
| 726 | if (c == '&') |
| 727 | { |
| 728 | cpy = re->startp[0]; |
| 729 | end = re->endp[0]; |
| 730 | } |
| 731 | else if (c == '~') |
| 732 | { |
| 733 | cpy = previous1; |
| 734 | if (cpy) |
| 735 | end = cpy + strlen(cpy); |
| 736 | } |
| 737 | else |
| 738 | if (c == '\\') |
| 739 | { |
| 740 | c = *src++; |
| 741 | switch (c) |
| 742 | { |
| 743 | case '0': |
| 744 | case '1': |
| 745 | case '2': |
| 746 | case '3': |
| 747 | case '4': |
| 748 | case '5': |
| 749 | case '6': |
| 750 | case '7': |
| 751 | case '8': |
| 752 | case '9': |
| 753 | /* \0 thru \9 mean "copy subexpression" */ |
| 754 | c -= '0'; |
| 755 | cpy = re->startp[(int)c]; |
| 756 | end = re->endp[(int)c]; |
| 757 | break; |
| 758 | case 'U': |
| 759 | case 'u': |
| 760 | case 'L': |
| 761 | case 'l': |
| 762 | /* \U and \L mean "convert to upper/lowercase" */ |
| 763 | mod = c; |
| 764 | continue; |
| 765 | |
| 766 | case 'E': |
| 767 | case 'e': |
| 768 | /* \E ends the \U or \L */ |
| 769 | mod = 0; |
| 770 | continue; |
| 771 | case '&': |
| 772 | /* "\&" means "original text" */ |
| 773 | *dst++ = c; |
| 774 | continue; |
| 775 | |
| 776 | case '~': |
| 777 | /* "\~" means "previous text, if any" */ |
| 778 | *dst++ = c; |
| 779 | continue; |
| 780 | default: |
| 781 | /* ordinary char preceded by backslash */ |
| 782 | *dst++ = c; |
| 783 | continue; |
| 784 | } |
| 785 | } |
| 786 | else |
| 787 | { |
| 788 | /* ordinary character, so just copy it */ |
| 789 | *dst++ = c; |
| 790 | continue; |
| 791 | } |
| 792 | |
| 793 | /* Note: to reach this point in the code, we must have evaded |
| 794 | * all "continue" statements. To do that, we must have hit |
| 795 | * a metacharacter that involves copying. |
| 796 | */ |
| 797 | |
| 798 | /* if there is nothing to copy, loop */ |
| 799 | if (!cpy) |
| 800 | continue; |
| 801 | |
| 802 | /* copy over a portion of the original */ |
| 803 | while (cpy < end) |
| 804 | { |
| 805 | switch (mod) |
| 806 | { |
| 807 | case 'U': |
| 808 | case 'u': |
| 809 | /* convert to uppercase */ |
| 810 | if (isascii(*cpy) && islower(*cpy)) |
| 811 | { |
| 812 | *dst++ = toupper(*cpy); |
| 813 | cpy++; |
| 814 | } |
| 815 | else |
| 816 | { |
| 817 | *dst++ = *cpy++; |
| 818 | } |
| 819 | break; |
| 820 | |
| 821 | case 'L': |
| 822 | case 'l': |
| 823 | /* convert to lowercase */ |
| 824 | if (isascii(*cpy) && isupper(*cpy)) |
| 825 | { |
| 826 | *dst++ = tolower(*cpy); |
| 827 | cpy++; |
| 828 | } |
| 829 | else |
| 830 | { |
| 831 | *dst++ = *cpy++; |
| 832 | } |
| 833 | break; |
| 834 | |
| 835 | default: |
| 836 | /* copy without any conversion */ |
| 837 | *dst++ = *cpy++; |
| 838 | } |
| 839 | |
| 840 | /* \u and \l end automatically after the first char */ |
| 841 | if (mod && (mod == 'u' || mod == 'l')) |
| 842 | { |
| 843 | mod = 0; |
| 844 | } |
| 845 | } |
| 846 | } |
| 847 | *dst = '\0'; |
| 848 | |
| 849 | /* remember what text we inserted this time */ |
| 850 | if (previous1) |
| 851 | free(previous1); |
| 852 | previous1 = (char *)malloc((unsigned)(strlen(start) + 1)); |
| 853 | if (previous1) |
| 854 | strcpy(previous1, start); |
| 855 | } |
Eric Andersen | 7f1acfd | 1999-10-29 23:09:13 +0000 | [diff] [blame] | 856 | #endif |
Eric Andersen | aa0765e | 1999-10-22 04:30:20 +0000 | [diff] [blame] | 857 | |
| 858 | #endif /* BB_REGEXP */ |
| 859 | |
| 860 | |