1 /* Definitions for data structures and routines for the regular 2 expression library, version 0.12. 3 4 Copyright (C) 1985, 1989, 1990, 1991, 1992, 1993 Free Software Foundation, Inc. 5 6 This program is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 2, or (at your option) 9 any later version. 10 11 This program is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with this program; if not, write to the Free Software 18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ 19 20 #ifndef __REGEXP_LIBRARY_H__ 21 #define __REGEXP_LIBRARY_H__ 22 23 /* POSIX says that <sys/types.h> must be included (by the caller) before 24 <regex.h>. */ 25 26 #ifdef VMS 27 /* VMS doesn't have `size_t' in <sys/types.h>, even though POSIX says it 28 should be there. */ 29 #include <stddef.h> 30 #endif 31 32 33 /* The following bits are used to determine the regexp syntax we 34 recognize. The set/not-set meanings are chosen so that Emacs syntax 35 remains the value 0. The bits are given in alphabetical order, and 36 the definitions shifted by one from the previous bit; thus, when we 37 add or remove a bit, only one other definition need change. */ 38 typedef unsigned reg_syntax_t; 39 40 /* If this bit is not set, then \ inside a bracket expression is literal. 41 If set, then such a \ quotes the following character. */ 42 #define RE_BACKSLASH_ESCAPE_IN_LISTS (1) 43 44 /* If this bit is not set, then + and ? are operators, and \+ and \? are 45 literals. 46 If set, then \+ and \? are operators and + and ? are literals. */ 47 #define RE_BK_PLUS_QM (RE_BACKSLASH_ESCAPE_IN_LISTS << 1) 48 49 /* If this bit is set, then character classes are supported. They are: 50 [:alpha:], [:upper:], [:lower:], [:digit:], [:alnum:], [:xdigit:], 51 [:space:], [:print:], [:punct:], [:graph:], and [:cntrl:]. 52 If not set, then character classes are not supported. */ 53 #define RE_CHAR_CLASSES (RE_BK_PLUS_QM << 1) 54 55 /* If this bit is set, then ^ and $ are always anchors (outside bracket 56 expressions, of course). 57 If this bit is not set, then it depends: 58 ^ is an anchor if it is at the beginning of a regular 59 expression or after an open-group or an alternation operator; 60 $ is an anchor if it is at the end of a regular expression, or 61 before a close-group or an alternation operator. 62 63 This bit could be (re)combined with RE_CONTEXT_INDEP_OPS, because 64 POSIX draft 11.2 says that * etc. in leading positions is undefined. 65 We already implemented a previous draft which made those constructs 66 invalid, though, so we haven't changed the code back. */ 67 #define RE_CONTEXT_INDEP_ANCHORS (RE_CHAR_CLASSES << 1) 68 69 /* If this bit is set, then special characters are always special 70 regardless of where they are in the pattern. 71 If this bit is not set, then special characters are special only in 72 some contexts; otherwise they are ordinary. Specifically, 73 * + ? and intervals are only special when not after the beginning, 74 open-group, or alternation operator. */ 75 #define RE_CONTEXT_INDEP_OPS (RE_CONTEXT_INDEP_ANCHORS << 1) 76 77 /* If this bit is set, then *, +, ?, and { cannot be first in an re or 78 immediately after an alternation or begin-group operator. */ 79 #define RE_CONTEXT_INVALID_OPS (RE_CONTEXT_INDEP_OPS << 1) 80 81 /* If this bit is set, then . matches newline. 82 If not set, then it doesn't. */ 83 #define RE_DOT_NEWLINE (RE_CONTEXT_INVALID_OPS << 1) 84 85 /* If this bit is set, then . doesn't match NUL. 86 If not set, then it does. */ 87 #define RE_DOT_NOT_NULL (RE_DOT_NEWLINE << 1) 88 89 /* If this bit is set, nonmatching lists [^...] do not match newline. 90 If not set, they do. */ 91 #define RE_HAT_LISTS_NOT_NEWLINE (RE_DOT_NOT_NULL << 1) 92 93 /* If this bit is set, either \{...\} or {...} defines an 94 interval, depending on RE_NO_BK_BRACES. 95 If not set, \{, \}, {, and } are literals. */ 96 #define RE_INTERVALS (RE_HAT_LISTS_NOT_NEWLINE << 1) 97 98 /* If this bit is set, +, ? and | aren't recognized as operators. 99 If not set, they are. */ 100 #define RE_LIMITED_OPS (RE_INTERVALS << 1) 101 102 /* If this bit is set, newline is an alternation operator. 103 If not set, newline is literal. */ 104 #define RE_NEWLINE_ALT (RE_LIMITED_OPS << 1) 105 106 /* If this bit is set, then `{...}' defines an interval, and \{ and \} 107 are literals. 108 If not set, then `\{...\}' defines an interval. */ 109 #define RE_NO_BK_BRACES (RE_NEWLINE_ALT << 1) 110 111 /* If this bit is set, (...) defines a group, and \( and \) are literals. 112 If not set, \(...\) defines a group, and ( and ) are literals. */ 113 #define RE_NO_BK_PARENS (RE_NO_BK_BRACES << 1) 114 115 /* If this bit is set, then \<digit> matches <digit>. 116 If not set, then \<digit> is a back-reference. */ 117 #define RE_NO_BK_REFS (RE_NO_BK_PARENS << 1) 118 119 /* If this bit is set, then | is an alternation operator, and \| is literal. 120 If not set, then \| is an alternation operator, and | is literal. */ 121 #define RE_NO_BK_VBAR (RE_NO_BK_REFS << 1) 122 123 /* If this bit is set, then an ending range point collating higher 124 than the starting range point, as in [z-a], is invalid. 125 If not set, then when ending range point collates higher than the 126 starting range point, the range is ignored. */ 127 #define RE_NO_EMPTY_RANGES (RE_NO_BK_VBAR << 1) 128 129 /* If this bit is set, then an unmatched ) is ordinary. 130 If not set, then an unmatched ) is invalid. */ 131 #define RE_UNMATCHED_RIGHT_PAREN_ORD (RE_NO_EMPTY_RANGES << 1) 132 133 /* This global variable defines the particular regexp syntax to use (for 134 some interfaces). When a regexp is compiled, the syntax used is 135 stored in the pattern buffer, so changing this does not affect 136 already-compiled regexps. */ 137 extern reg_syntax_t re_syntax_options; 138 139 /* Define combinations of the above bits for the standard possibilities. 140 (The [[[ comments delimit what gets put into the Texinfo file, so 141 don't delete them!) */ 142 /* [[[begin syntaxes]]] */ 143 #define RE_SYNTAX_EMACS 0 144 145 #define RE_SYNTAX_AWK \ 146 (RE_BACKSLASH_ESCAPE_IN_LISTS | RE_DOT_NOT_NULL \ 147 | RE_NO_BK_PARENS | RE_NO_BK_REFS \ 148 | RE_NO_BK_VBAR | RE_NO_EMPTY_RANGES \ 149 | RE_UNMATCHED_RIGHT_PAREN_ORD) 150 151 #define RE_SYNTAX_POSIX_AWK \ 152 (RE_SYNTAX_POSIX_EXTENDED | RE_BACKSLASH_ESCAPE_IN_LISTS) 153 154 #define RE_SYNTAX_GREP \ 155 (RE_BK_PLUS_QM | RE_CHAR_CLASSES \ 156 | RE_HAT_LISTS_NOT_NEWLINE | RE_INTERVALS \ 157 | RE_NEWLINE_ALT) 158 159 #define RE_SYNTAX_EGREP \ 160 (RE_CHAR_CLASSES | RE_CONTEXT_INDEP_ANCHORS \ 161 | RE_CONTEXT_INDEP_OPS | RE_HAT_LISTS_NOT_NEWLINE \ 162 | RE_NEWLINE_ALT | RE_NO_BK_PARENS \ 163 | RE_NO_BK_VBAR) 164 165 #define RE_SYNTAX_POSIX_EGREP \ 166 (RE_SYNTAX_EGREP | RE_INTERVALS | RE_NO_BK_BRACES) 167 168 /* P1003.2/D11.2, section 4.20.7.1, lines 5078ff. */ 169 #define RE_SYNTAX_ED RE_SYNTAX_POSIX_BASIC 170 171 #define RE_SYNTAX_SED RE_SYNTAX_POSIX_BASIC 172 173 /* Syntax bits common to both basic and extended POSIX regex syntax. */ 174 #define _RE_SYNTAX_POSIX_COMMON \ 175 (RE_CHAR_CLASSES | RE_DOT_NEWLINE | RE_DOT_NOT_NULL \ 176 | RE_INTERVALS | RE_NO_EMPTY_RANGES) 177 178 #define RE_SYNTAX_POSIX_BASIC \ 179 (_RE_SYNTAX_POSIX_COMMON | RE_BK_PLUS_QM) 180 181 /* Differs from ..._POSIX_BASIC only in that RE_BK_PLUS_QM becomes 182 RE_LIMITED_OPS, i.e., \? \+ \| are not recognized. Actually, this 183 isn't minimal, since other operators, such as \`, aren't disabled. */ 184 #define RE_SYNTAX_POSIX_MINIMAL_BASIC \ 185 (_RE_SYNTAX_POSIX_COMMON | RE_LIMITED_OPS) 186 187 #define RE_SYNTAX_POSIX_EXTENDED \ 188 (_RE_SYNTAX_POSIX_COMMON | RE_CONTEXT_INDEP_ANCHORS \ 189 | RE_CONTEXT_INDEP_OPS | RE_NO_BK_BRACES \ 190 | RE_NO_BK_PARENS | RE_NO_BK_VBAR \ 191 | RE_UNMATCHED_RIGHT_PAREN_ORD) 192 193 /* Differs from ..._POSIX_EXTENDED in that RE_CONTEXT_INVALID_OPS 194 replaces RE_CONTEXT_INDEP_OPS and RE_NO_BK_REFS is added. */ 195 #define RE_SYNTAX_POSIX_MINIMAL_EXTENDED \ 196 (_RE_SYNTAX_POSIX_COMMON | RE_CONTEXT_INDEP_ANCHORS \ 197 | RE_CONTEXT_INVALID_OPS | RE_NO_BK_BRACES \ 198 | RE_NO_BK_PARENS | RE_NO_BK_REFS \ 199 | RE_NO_BK_VBAR | RE_UNMATCHED_RIGHT_PAREN_ORD) 200 /* [[[end syntaxes]]] */ 201 202 /* Maximum number of duplicates an interval can allow. Some systems 203 (erroneously) define this in other header files, but we want our 204 value, so remove any previous define. */ 205 #ifdef RE_DUP_MAX 206 #undef RE_DUP_MAX 207 #endif 208 #define RE_DUP_MAX ((1 << 15) - 1) 209 210 211 /* POSIX `cflags' bits (i.e., information for `regcomp'). */ 212 213 /* If this bit is set, then use extended regular expression syntax. 214 If not set, then use basic regular expression syntax. */ 215 #define REG_EXTENDED 1 216 217 /* If this bit is set, then ignore case when matching. 218 If not set, then case is significant. */ 219 #define REG_ICASE (REG_EXTENDED << 1) 220 221 /* If this bit is set, then anchors do not match at newline 222 characters in the string. 223 If not set, then anchors do match at newlines. */ 224 #define REG_NEWLINE (REG_ICASE << 1) 225 226 /* If this bit is set, then report only success or fail in regexec. 227 If not set, then returns differ between not matching and errors. */ 228 #define REG_NOSUB (REG_NEWLINE << 1) 229 230 231 /* POSIX `eflags' bits (i.e., information for regexec). */ 232 233 /* If this bit is set, then the beginning-of-line operator doesn't match 234 the beginning of the string (presumably because it's not the 235 beginning of a line). 236 If not set, then the beginning-of-line operator does match the 237 beginning of the string. */ 238 #define REG_NOTBOL 1 239 240 /* Like REG_NOTBOL, except for the end-of-line. */ 241 #define REG_NOTEOL (1 << 1) 242 243 244 /* If any error codes are removed, changed, or added, update the 245 `re_error_msg' table in regex.c. */ 246 typedef enum 247 { 248 REG_NOERROR = 0, /* Success. */ 249 REG_NOMATCH, /* Didn't find a match (for regexec). */ 250 251 /* POSIX regcomp return error codes. (In the order listed in the 252 standard.) */ 253 REG_BADPAT, /* Invalid pattern. */ 254 REG_ECOLLATE, /* Not implemented. */ 255 REG_ECTYPE, /* Invalid character class name. */ 256 REG_EESCAPE, /* Trailing backslash. */ 257 REG_ESUBREG, /* Invalid back reference. */ 258 REG_EBRACK, /* Unmatched left bracket. */ 259 REG_EPAREN, /* Parenthesis imbalance. */ 260 REG_EBRACE, /* Unmatched \{. */ 261 REG_BADBR, /* Invalid contents of \{\}. */ 262 REG_ERANGE, /* Invalid range end. */ 263 REG_ESPACE, /* Ran out of memory. */ 264 REG_BADRPT, /* No preceding re for repetition op. */ 265 266 /* Error codes we've added. */ 267 REG_EEND, /* Premature end. */ 268 REG_ESIZE, /* Compiled pattern bigger than 2^16 bytes. */ 269 REG_ERPAREN /* Unmatched ) or \); not returned from regcomp. */ 270 } reg_errcode_t; 271 272 /* This data structure represents a compiled pattern. Before calling 273 the pattern compiler, the fields `buffer', `allocated', `fastmap', 274 `translate', and `no_sub' can be set. After the pattern has been 275 compiled, the `re_nsub' field is available. All other fields are 276 private to the regex routines. */ 277 278 struct re_pattern_buffer 279 { 280 /* [[[begin pattern_buffer]]] */ 281 /* Space that holds the compiled pattern. It is declared as 282 `unsigned char *' because its elements are 283 sometimes used as array indexes. */ 284 unsigned char *buffer; 285 286 /* Number of bytes to which `buffer' points. */ 287 unsigned long allocated; 288 289 /* Number of bytes actually used in `buffer'. */ 290 unsigned long used; 291 292 /* Syntax setting with which the pattern was compiled. */ 293 reg_syntax_t syntax; 294 295 /* Pointer to a fastmap, if any, otherwise zero. re_search uses 296 the fastmap, if there is one, to skip over impossible 297 starting points for matches. */ 298 char *fastmap; 299 300 /* Either a translate table to apply to all characters before 301 comparing them, or zero for no translation. The translation 302 is applied to a pattern when it is compiled and to a string 303 when it is matched. */ 304 char *translate; 305 306 /* Number of subexpressions found by the compiler. */ 307 size_t re_nsub; 308 309 /* Zero if this pattern cannot match the empty string, one else. 310 Well, in truth it's used only in `re_search_2', to see 311 whether or not we should use the fastmap, so we don't set 312 this absolutely perfectly; see `re_compile_fastmap' (the 313 `duplicate' case). */ 314 unsigned can_be_null : 1; 315 316 /* If REGS_UNALLOCATED, allocate space in the `regs' structure 317 for `max (RE_NREGS, re_nsub + 1)' groups. 318 If REGS_REALLOCATE, reallocate space if necessary. 319 If REGS_FIXED, use what's there. */ 320 #define REGS_UNALLOCATED 0 321 #define REGS_REALLOCATE 1 322 #define REGS_FIXED 2 323 unsigned regs_allocated : 2; 324 325 /* Set to zero when `regex_compile' compiles a pattern; set to one 326 by `re_compile_fastmap' if it updates the fastmap. */ 327 unsigned fastmap_accurate : 1; 328 329 /* If set, `re_match_2' does not return information about 330 subexpressions. */ 331 unsigned no_sub : 1; 332 333 /* If set, a beginning-of-line anchor doesn't match at the 334 beginning of the string. */ 335 unsigned not_bol : 1; 336 337 /* Similarly for an end-of-line anchor. */ 338 unsigned not_eol : 1; 339 340 /* If true, an anchor at a newline matches. */ 341 unsigned newline_anchor : 1; 342 343 /* [[[end pattern_buffer]]] */ 344 }; 345 346 typedef struct re_pattern_buffer regex_t; 347 348 349 /* search.c (search_buffer) in Emacs needs this one opcode value. It is 350 defined both in `regex.c' and here. */ 351 #define RE_EXACTN_VALUE 1 352 353 /* Type for byte offsets within the string. POSIX mandates this. */ 354 typedef int regoff_t; 355 356 357 /* This is the structure we store register match data in. See 358 regex.texinfo for a full description of what registers match. */ 359 struct re_registers 360 { 361 unsigned num_regs; 362 regoff_t *start; 363 regoff_t *end; 364 }; 365 366 367 /* If `regs_allocated' is REGS_UNALLOCATED in the pattern buffer, 368 `re_match_2' returns information about at least this many registers 369 the first time a `regs' structure is passed. */ 370 #ifndef RE_NREGS 371 #define RE_NREGS 30 372 #endif 373 374 375 /* POSIX specification for registers. Aside from the different names than 376 `re_registers', POSIX uses an array of structures, instead of a 377 structure of arrays. */ 378 typedef struct 379 { 380 regoff_t rm_so; /* Byte offset from string's start to substring's start. */ 381 regoff_t rm_eo; /* Byte offset from string's start to substring's end. */ 382 } regmatch_t; 383 384 /* Declarations for routines. */ 385 386 /* To avoid duplicating every routine declaration -- once with a 387 prototype (if we are ANSI), and once without (if we aren't) -- we 388 use the following macro to declare argument types. This 389 unfortunately clutters up the declarations a bit, but I think it's 390 worth it. */ 391 392 #if __STDC__ 393 394 #define _RE_ARGS(args) args 395 396 #else /* not __STDC__ */ 397 398 #define _RE_ARGS(args) () 399 400 #endif /* not __STDC__ */ 401 402 __BEGIN_DECLS 403 404 /* Sets the current default syntax to SYNTAX, and return the old syntax. 405 You can also simply assign to the `re_syntax_options' variable. */ 406 extern reg_syntax_t re_set_syntax _RE_ARGS ((reg_syntax_t syntax)); 407 408 /* Compile the regular expression PATTERN, with length LENGTH 409 and syntax given by the global `re_syntax_options', into the buffer 410 BUFFER. Return NULL if successful, and an error string if not. */ 411 extern const char *re_compile_pattern 412 _RE_ARGS ((const char *pattern, int length, 413 struct re_pattern_buffer *buffer)); 414 415 416 /* Compile a fastmap for the compiled pattern in BUFFER; used to 417 accelerate searches. Return 0 if successful and -2 if was an 418 internal error. */ 419 extern int re_compile_fastmap _RE_ARGS ((struct re_pattern_buffer *buffer)); 420 421 422 /* Search in the string STRING (with length LENGTH) for the pattern 423 compiled into BUFFER. Start searching at position START, for RANGE 424 characters. Return the starting position of the match, -1 for no 425 match, or -2 for an internal error. Also return register 426 information in REGS (if REGS and BUFFER->no_sub are nonzero). */ 427 extern int re_search 428 _RE_ARGS ((struct re_pattern_buffer *buffer, const char *string, 429 int length, int start, int range, struct re_registers *regs)); 430 431 432 /* Like `re_search', but search in the concatenation of STRING1 and 433 STRING2. Also, stop searching at index START + STOP. */ 434 extern int re_search_2 435 _RE_ARGS ((struct re_pattern_buffer *buffer, const char *string1, 436 int length1, const char *string2, int length2, 437 int start, int range, struct re_registers *regs, int stop)); 438 439 440 /* Like `re_search', but return how many characters in STRING the regexp 441 in BUFFER matched, starting at position START. */ 442 extern int re_match 443 _RE_ARGS ((struct re_pattern_buffer *buffer, const char *string, 444 int length, int start, struct re_registers *regs)); 445 446 447 /* Relates to `re_match' as `re_search_2' relates to `re_search'. */ 448 extern int re_match_2 449 _RE_ARGS ((struct re_pattern_buffer *buffer, const char *string1, 450 int length1, const char *string2, int length2, 451 int start, struct re_registers *regs, int stop)); 452 453 454 /* Set REGS to hold NUM_REGS registers, storing them in STARTS and 455 ENDS. Subsequent matches using BUFFER and REGS will use this memory 456 for recording register information. STARTS and ENDS must be 457 allocated with malloc, and must each be at least `NUM_REGS * sizeof 458 (regoff_t)' bytes long. 459 460 If NUM_REGS == 0, then subsequent matches should allocate their own 461 register data. 462 463 Unless this function is called, the first search or match using 464 PATTERN_BUFFER will allocate its own register data, without 465 freeing the old data. */ 466 extern void re_set_registers 467 _RE_ARGS ((struct re_pattern_buffer *buffer, struct re_registers *regs, 468 unsigned num_regs, regoff_t *starts, regoff_t *ends)); 469 470 /* 4.2 bsd compatibility. */ 471 extern char *re_comp _RE_ARGS ((const char *)); 472 extern int re_exec _RE_ARGS ((const char *)); 473 474 /* POSIX compatibility. */ 475 extern int regcomp _RE_ARGS ((regex_t *preg, const char *pattern, int cflags)); 476 extern int regexec 477 _RE_ARGS ((const regex_t *preg, const char *string, size_t nmatch, 478 regmatch_t pmatch[], int eflags)); 479 extern size_t regerror 480 _RE_ARGS ((int errcode, const regex_t *preg, char *errbuf, 481 size_t errbuf_size)); 482 extern void regfree _RE_ARGS ((regex_t *preg)); 483 484 __END_DECLS 485 486 #endif /* not __REGEXP_LIBRARY_H__ */ 487 488 /* 489 Local variables: 490 make-backup-files: t 491 version-control: t 492 trim-versions-without-asking: nil 493 End: 494 */ 495