regex.h revision 30578
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/* Allow the use in C++ code. */ 24#ifdef __cplusplus 25extern "C" { 26#endif 27 28/* POSIX says that <sys/types.h> must be included (by the caller) before 29 <regex.h>. */ 30 31#ifdef VMS 32/* VMS doesn't have `size_t' in <sys/types.h>, even though POSIX says it 33 should be there. */ 34#include <stddef.h> 35#endif 36 37 38/* The following two types have to be signed and unsigned integer type 39 wide enough to hold a value of a pointer. For most ANSI compilers 40 ptrdiff_t and size_t should be likely OK. Still size of these two 41 types is 2 for Microsoft C. Ugh... */ 42typedef long s_reg_t; 43typedef unsigned long active_reg_t; 44 45/* The following bits are used to determine the regexp syntax we 46 recognize. The set/not-set meanings are chosen so that Emacs syntax 47 remains the value 0. The bits are given in alphabetical order, and 48 the definitions shifted by one from the previous bit; thus, when we 49 add or remove a bit, only one other definition need change. */ 50typedef unsigned long reg_syntax_t; 51 52/* If this bit is not set, then \ inside a bracket expression is literal. 53 If set, then such a \ quotes the following character. */ 54#define RE_BACKSLASH_ESCAPE_IN_LISTS (1L) 55 56/* If this bit is not set, then + and ? are operators, and \+ and \? are 57 literals. 58 If set, then \+ and \? are operators and + and ? are literals. */ 59#define RE_BK_PLUS_QM (RE_BACKSLASH_ESCAPE_IN_LISTS << 1) 60 61/* If this bit is set, then character classes are supported. They are: 62 [:alpha:], [:upper:], [:lower:], [:digit:], [:alnum:], [:xdigit:], 63 [:space:], [:print:], [:punct:], [:graph:], and [:cntrl:]. 64 If not set, then character classes are not supported. */ 65#define RE_CHAR_CLASSES (RE_BK_PLUS_QM << 1) 66 67/* If this bit is set, then ^ and $ are always anchors (outside bracket 68 expressions, of course). 69 If this bit is not set, then it depends: 70 ^ is an anchor if it is at the beginning of a regular 71 expression or after an open-group or an alternation operator; 72 $ is an anchor if it is at the end of a regular expression, or 73 before a close-group or an alternation operator. 74 75 This bit could be (re)combined with RE_CONTEXT_INDEP_OPS, because 76 POSIX draft 11.2 says that * etc. in leading positions is undefined. 77 We already implemented a previous draft which made those constructs 78 invalid, though, so we haven't changed the code back. */ 79#define RE_CONTEXT_INDEP_ANCHORS (RE_CHAR_CLASSES << 1) 80 81/* If this bit is set, then special characters are always special 82 regardless of where they are in the pattern. 83 If this bit is not set, then special characters are special only in 84 some contexts; otherwise they are ordinary. Specifically, 85 * + ? and intervals are only special when not after the beginning, 86 open-group, or alternation operator. */ 87#define RE_CONTEXT_INDEP_OPS (RE_CONTEXT_INDEP_ANCHORS << 1) 88 89/* If this bit is set, then *, +, ?, and { cannot be first in an re or 90 immediately after an alternation or begin-group operator. */ 91#define RE_CONTEXT_INVALID_OPS (RE_CONTEXT_INDEP_OPS << 1) 92 93/* If this bit is set, then . matches newline. 94 If not set, then it doesn't. */ 95#define RE_DOT_NEWLINE (RE_CONTEXT_INVALID_OPS << 1) 96 97/* If this bit is set, then . doesn't match NUL. 98 If not set, then it does. */ 99#define RE_DOT_NOT_NULL (RE_DOT_NEWLINE << 1) 100 101/* If this bit is set, nonmatching lists [^...] do not match newline. 102 If not set, they do. */ 103#define RE_HAT_LISTS_NOT_NEWLINE (RE_DOT_NOT_NULL << 1) 104 105/* If this bit is set, either \{...\} or {...} defines an 106 interval, depending on RE_NO_BK_BRACES. 107 If not set, \{, \}, {, and } are literals. */ 108#define RE_INTERVALS (RE_HAT_LISTS_NOT_NEWLINE << 1) 109 110/* If this bit is set, +, ? and | aren't recognized as operators. 111 If not set, they are. */ 112#define RE_LIMITED_OPS (RE_INTERVALS << 1) 113 114/* If this bit is set, newline is an alternation operator. 115 If not set, newline is literal. */ 116#define RE_NEWLINE_ALT (RE_LIMITED_OPS << 1) 117 118/* If this bit is set, then `{...}' defines an interval, and \{ and \} 119 are literals. 120 If not set, then `\{...\}' defines an interval. */ 121#define RE_NO_BK_BRACES (RE_NEWLINE_ALT << 1) 122 123/* If this bit is set, (...) defines a group, and \( and \) are literals. 124 If not set, \(...\) defines a group, and ( and ) are literals. */ 125#define RE_NO_BK_PARENS (RE_NO_BK_BRACES << 1) 126 127/* If this bit is set, then \<digit> matches <digit>. 128 If not set, then \<digit> is a back-reference. */ 129#define RE_NO_BK_REFS (RE_NO_BK_PARENS << 1) 130 131/* If this bit is set, then | is an alternation operator, and \| is literal. 132 If not set, then \| is an alternation operator, and | is literal. */ 133#define RE_NO_BK_VBAR (RE_NO_BK_REFS << 1) 134 135/* If this bit is set, then an ending range point collating higher 136 than the starting range point, as in [z-a], is invalid. 137 If not set, then when ending range point collates higher than the 138 starting range point, the range is ignored. */ 139#define RE_NO_EMPTY_RANGES (RE_NO_BK_VBAR << 1) 140 141/* If this bit is set, then an unmatched ) is ordinary. 142 If not set, then an unmatched ) is invalid. */ 143#define RE_UNMATCHED_RIGHT_PAREN_ORD (RE_NO_EMPTY_RANGES << 1) 144 145/* If this bit is set, do not process the GNU regex operators. 146 IF not set, then the GNU regex operators are recognized. */ 147#define RE_NO_GNU_OPS (RE_UNMATCHED_RIGHT_PAREN_ORD << 1) 148 149/* This global variable defines the particular regexp syntax to use (for 150 some interfaces). When a regexp is compiled, the syntax used is 151 stored in the pattern buffer, so changing this does not affect 152 already-compiled regexps. */ 153extern reg_syntax_t re_syntax_options; 154 155/* Define combinations of the above bits for the standard possibilities. 156 (The [[[ comments delimit what gets put into the Texinfo file, so 157 don't delete them!) */ 158/* [[[begin syntaxes]]] */ 159#define RE_SYNTAX_EMACS 0 160 161#define RE_SYNTAX_AWK \ 162 (RE_BACKSLASH_ESCAPE_IN_LISTS | RE_DOT_NOT_NULL \ 163 | RE_NO_BK_PARENS | RE_NO_BK_REFS \ 164 | RE_NO_BK_VBAR | RE_NO_EMPTY_RANGES \ 165 | RE_DOT_NEWLINE | RE_CONTEXT_INDEP_ANCHORS \ 166 | RE_UNMATCHED_RIGHT_PAREN_ORD | RE_NO_GNU_OPS) 167 168#define RE_SYNTAX_GNU_AWK \ 169 ((RE_SYNTAX_POSIX_EXTENDED | RE_BACKSLASH_ESCAPE_IN_LISTS) \ 170 & ~(RE_DOT_NOT_NULL | RE_INTERVALS | RE_CONTEXT_INDEP_OPS)) 171 172#define RE_SYNTAX_POSIX_AWK \ 173 (RE_SYNTAX_POSIX_EXTENDED | RE_BACKSLASH_ESCAPE_IN_LISTS \ 174 | RE_INTERVALS | RE_NO_GNU_OPS) 175 176#define RE_SYNTAX_GREP \ 177 (RE_BK_PLUS_QM | RE_CHAR_CLASSES \ 178 | RE_HAT_LISTS_NOT_NEWLINE | RE_INTERVALS \ 179 | RE_NEWLINE_ALT) 180 181#define RE_SYNTAX_EGREP \ 182 (RE_CHAR_CLASSES | RE_CONTEXT_INDEP_ANCHORS \ 183 | RE_CONTEXT_INDEP_OPS | RE_HAT_LISTS_NOT_NEWLINE \ 184 | RE_NEWLINE_ALT | RE_NO_BK_PARENS \ 185 | RE_NO_BK_VBAR) 186 187#define RE_SYNTAX_POSIX_EGREP \ 188 (RE_SYNTAX_EGREP | RE_INTERVALS | RE_NO_BK_BRACES) 189 190/* P1003.2/D11.2, section 4.20.7.1, lines 5078ff. */ 191#define RE_SYNTAX_ED RE_SYNTAX_POSIX_BASIC 192 193#define RE_SYNTAX_SED RE_SYNTAX_POSIX_BASIC 194 195/* Syntax bits common to both basic and extended POSIX regex syntax. */ 196#define _RE_SYNTAX_POSIX_COMMON \ 197 (RE_CHAR_CLASSES | RE_DOT_NEWLINE | RE_DOT_NOT_NULL \ 198 | RE_INTERVALS | RE_NO_EMPTY_RANGES) 199 200#define RE_SYNTAX_POSIX_BASIC \ 201 (_RE_SYNTAX_POSIX_COMMON | RE_BK_PLUS_QM) 202 203/* Differs from ..._POSIX_BASIC only in that RE_BK_PLUS_QM becomes 204 RE_LIMITED_OPS, i.e., \? \+ \| are not recognized. Actually, this 205 isn't minimal, since other operators, such as \`, aren't disabled. */ 206#define RE_SYNTAX_POSIX_MINIMAL_BASIC \ 207 (_RE_SYNTAX_POSIX_COMMON | RE_LIMITED_OPS) 208 209#define RE_SYNTAX_POSIX_EXTENDED \ 210 (_RE_SYNTAX_POSIX_COMMON | RE_CONTEXT_INDEP_ANCHORS \ 211 | RE_CONTEXT_INDEP_OPS | RE_NO_BK_BRACES \ 212 | RE_NO_BK_PARENS | RE_NO_BK_VBAR \ 213 | RE_UNMATCHED_RIGHT_PAREN_ORD) 214 215/* Differs from ..._POSIX_EXTENDED in that RE_CONTEXT_INVALID_OPS 216 replaces RE_CONTEXT_INDEP_OPS and RE_NO_BK_REFS is added. */ 217#define RE_SYNTAX_POSIX_MINIMAL_EXTENDED \ 218 (_RE_SYNTAX_POSIX_COMMON | RE_CONTEXT_INDEP_ANCHORS \ 219 | RE_CONTEXT_INVALID_OPS | RE_NO_BK_BRACES \ 220 | RE_NO_BK_PARENS | RE_NO_BK_REFS \ 221 | RE_NO_BK_VBAR | RE_UNMATCHED_RIGHT_PAREN_ORD) 222/* [[[end syntaxes]]] */ 223 224/* Maximum number of duplicates an interval can allow. Some systems 225 (erroneously) define this in other header files, but we want our 226 value, so remove any previous define. */ 227#ifdef RE_DUP_MAX 228#undef RE_DUP_MAX 229#endif 230/* if sizeof(int) == 2, then ((1 << 15) - 1) overflows */ 231#define RE_DUP_MAX (0x7fff) 232 233 234/* POSIX `cflags' bits (i.e., information for `regcomp'). */ 235 236/* If this bit is set, then use extended regular expression syntax. 237 If not set, then use basic regular expression syntax. */ 238#define REG_EXTENDED 1 239 240/* If this bit is set, then ignore case when matching. 241 If not set, then case is significant. */ 242#define REG_ICASE (REG_EXTENDED << 1) 243 244/* If this bit is set, then anchors do not match at newline 245 characters in the string. 246 If not set, then anchors do match at newlines. */ 247#define REG_NEWLINE (REG_ICASE << 1) 248 249/* If this bit is set, then report only success or fail in regexec. 250 If not set, then returns differ between not matching and errors. */ 251#define REG_NOSUB (REG_NEWLINE << 1) 252 253 254/* POSIX `eflags' bits (i.e., information for regexec). */ 255 256/* If this bit is set, then the beginning-of-line operator doesn't match 257 the beginning of the string (presumably because it's not the 258 beginning of a line). 259 If not set, then the beginning-of-line operator does match the 260 beginning of the string. */ 261#define REG_NOTBOL 1 262 263/* Like REG_NOTBOL, except for the end-of-line. */ 264#define REG_NOTEOL (1 << 1) 265 266 267/* If any error codes are removed, changed, or added, update the 268 `re_error_msg' table in regex.c. */ 269typedef enum 270{ 271 REG_NOERROR = 0, /* Success. */ 272 REG_NOMATCH, /* Didn't find a match (for regexec). */ 273 274 /* POSIX regcomp return error codes. (In the order listed in the 275 standard.) */ 276 REG_BADPAT, /* Invalid pattern. */ 277 REG_ECOLLATE, /* Not implemented. */ 278 REG_ECTYPE, /* Invalid character class name. */ 279 REG_EESCAPE, /* Trailing backslash. */ 280 REG_ESUBREG, /* Invalid back reference. */ 281 REG_EBRACK, /* Unmatched left bracket. */ 282 REG_EPAREN, /* Parenthesis imbalance. */ 283 REG_EBRACE, /* Unmatched \{. */ 284 REG_BADBR, /* Invalid contents of \{\}. */ 285 REG_ERANGE, /* Invalid range end. */ 286 REG_ESPACE, /* Ran out of memory. */ 287 REG_BADRPT, /* No preceding re for repetition op. */ 288 289 /* Error codes we've added. */ 290 REG_EEND, /* Premature end. */ 291 REG_ESIZE, /* Compiled pattern bigger than 2^16 bytes. */ 292 REG_ERPAREN /* Unmatched ) or \); not returned from regcomp. */ 293} reg_errcode_t; 294 295/* This data structure represents a compiled pattern. Before calling 296 the pattern compiler, the fields `buffer', `allocated', `fastmap', 297 `translate', and `no_sub' can be set. After the pattern has been 298 compiled, the `re_nsub' field is available. All other fields are 299 private to the regex routines. */ 300 301struct re_pattern_buffer 302{ 303/* [[[begin pattern_buffer]]] */ 304 /* Space that holds the compiled pattern. It is declared as 305 `unsigned char *' because its elements are 306 sometimes used as array indexes. */ 307 unsigned char *buffer; 308 309 /* Number of bytes to which `buffer' points. */ 310 unsigned long allocated; 311 312 /* Number of bytes actually used in `buffer'. */ 313 unsigned long used; 314 315 /* Syntax setting with which the pattern was compiled. */ 316 reg_syntax_t syntax; 317 318 /* Pointer to a fastmap, if any, otherwise zero. re_search uses 319 the fastmap, if there is one, to skip over impossible 320 starting points for matches. */ 321 char *fastmap; 322 323 /* Either a translate table to apply to all characters before 324 comparing them, or zero for no translation. The translation 325 is applied to a pattern when it is compiled and to a string 326 when it is matched. */ 327 char *translate; 328 329 /* Number of subexpressions found by the compiler. */ 330 size_t re_nsub; 331 332 /* Zero if this pattern cannot match the empty string, one else. 333 Well, in truth it's used only in `re_search_2', to see 334 whether or not we should use the fastmap, so we don't set 335 this absolutely perfectly; see `re_compile_fastmap' (the 336 `duplicate' case). */ 337 unsigned can_be_null : 1; 338 339 /* If REGS_UNALLOCATED, allocate space in the `regs' structure 340 for `max (RE_NREGS, re_nsub + 1)' groups. 341 If REGS_REALLOCATE, reallocate space if necessary. 342 If REGS_FIXED, use what's there. */ 343#define REGS_UNALLOCATED 0 344#define REGS_REALLOCATE 1 345#define REGS_FIXED 2 346 unsigned regs_allocated : 2; 347 348 /* Set to zero when `regex_compile' compiles a pattern; set to one 349 by `re_compile_fastmap' if it updates the fastmap. */ 350 unsigned fastmap_accurate : 1; 351 352 /* If set, `re_match_2' does not return information about 353 subexpressions. */ 354 unsigned no_sub : 1; 355 356 /* If set, a beginning-of-line anchor doesn't match at the 357 beginning of the string. */ 358 unsigned not_bol : 1; 359 360 /* Similarly for an end-of-line anchor. */ 361 unsigned not_eol : 1; 362 363 /* If true, an anchor at a newline matches. */ 364 unsigned newline_anchor : 1; 365 366/* [[[end pattern_buffer]]] */ 367}; 368 369typedef struct re_pattern_buffer regex_t; 370 371 372/* search.c (search_buffer) in Emacs needs this one opcode value. It is 373 defined both in `regex.c' and here. */ 374#define RE_EXACTN_VALUE 1 375 376/* Type for byte offsets within the string. POSIX mandates this. */ 377typedef int regoff_t; 378 379 380/* This is the structure we store register match data in. See 381 regex.texinfo for a full description of what registers match. */ 382struct re_registers 383{ 384 unsigned num_regs; 385 regoff_t *start; 386 regoff_t *end; 387}; 388 389 390/* If `regs_allocated' is REGS_UNALLOCATED in the pattern buffer, 391 `re_match_2' returns information about at least this many registers 392 the first time a `regs' structure is passed. */ 393#ifndef RE_NREGS 394#define RE_NREGS 30 395#endif 396 397 398/* POSIX specification for registers. Aside from the different names than 399 `re_registers', POSIX uses an array of structures, instead of a 400 structure of arrays. */ 401typedef struct 402{ 403 regoff_t rm_so; /* Byte offset from string's start to substring's start. */ 404 regoff_t rm_eo; /* Byte offset from string's start to substring's end. */ 405} regmatch_t; 406 407/* Declarations for routines. */ 408 409/* To avoid duplicating every routine declaration -- once with a 410 prototype (if we are ANSI), and once without (if we aren't) -- we 411 use the following macro to declare argument types. This 412 unfortunately clutters up the declarations a bit, but I think it's 413 worth it. */ 414 415#ifdef __STDC__ 416 417#define _RE_ARGS(args) args 418 419#else /* not __STDC__ */ 420 421#define _RE_ARGS(args) () 422 423#endif /* not __STDC__ */ 424 425/* Sets the current default syntax to SYNTAX, and return the old syntax. 426 You can also simply assign to the `re_syntax_options' variable. */ 427extern reg_syntax_t re_set_syntax _RE_ARGS ((reg_syntax_t syntax)); 428 429/* Compile the regular expression PATTERN, with length LENGTH 430 and syntax given by the global `re_syntax_options', into the buffer 431 BUFFER. Return NULL if successful, and an error string if not. */ 432extern const char *re_compile_pattern 433 _RE_ARGS ((const char *pattern, size_t length, 434 struct re_pattern_buffer *buffer)); 435 436 437/* Compile a fastmap for the compiled pattern in BUFFER; used to 438 accelerate searches. Return 0 if successful and -2 if was an 439 internal error. */ 440extern int re_compile_fastmap _RE_ARGS ((struct re_pattern_buffer *buffer)); 441 442 443/* Search in the string STRING (with length LENGTH) for the pattern 444 compiled into BUFFER. Start searching at position START, for RANGE 445 characters. Return the starting position of the match, -1 for no 446 match, or -2 for an internal error. Also return register 447 information in REGS (if REGS and BUFFER->no_sub are nonzero). */ 448extern int re_search 449 _RE_ARGS ((struct re_pattern_buffer *buffer, const char *string, 450 int length, int start, int range, struct re_registers *regs)); 451 452 453/* Like `re_search', but search in the concatenation of STRING1 and 454 STRING2. Also, stop searching at index START + STOP. */ 455extern int re_search_2 456 _RE_ARGS ((struct re_pattern_buffer *buffer, const char *string1, 457 int length1, const char *string2, int length2, 458 int start, int range, struct re_registers *regs, int stop)); 459 460 461/* Like `re_search', but return how many characters in STRING the regexp 462 in BUFFER matched, starting at position START. */ 463extern int re_match 464 _RE_ARGS ((struct re_pattern_buffer *buffer, const char *string, 465 int length, int start, struct re_registers *regs)); 466 467 468/* Relates to `re_match' as `re_search_2' relates to `re_search'. */ 469extern int re_match_2 470 _RE_ARGS ((struct re_pattern_buffer *buffer, const char *string1, 471 int length1, const char *string2, int length2, 472 int start, struct re_registers *regs, int stop)); 473 474 475/* Set REGS to hold NUM_REGS registers, storing them in STARTS and 476 ENDS. Subsequent matches using BUFFER and REGS will use this memory 477 for recording register information. STARTS and ENDS must be 478 allocated with malloc, and must each be at least `NUM_REGS * sizeof 479 (regoff_t)' bytes long. 480 481 If NUM_REGS == 0, then subsequent matches should allocate their own 482 register data. 483 484 Unless this function is called, the first search or match using 485 PATTERN_BUFFER will allocate its own register data, without 486 freeing the old data. */ 487extern void re_set_registers 488 _RE_ARGS ((struct re_pattern_buffer *buffer, struct re_registers *regs, 489 unsigned num_regs, regoff_t *starts, regoff_t *ends)); 490 491/* 4.2 bsd compatibility. */ 492extern char *re_comp _RE_ARGS ((const char *)); 493extern int re_exec _RE_ARGS ((const char *)); 494 495/* POSIX compatibility. */ 496extern int regcomp _RE_ARGS ((regex_t *preg, const char *pattern, int cflags)); 497extern int regexec 498 _RE_ARGS ((const regex_t *preg, const char *string, size_t nmatch, 499 regmatch_t pmatch[], int eflags)); 500extern size_t regerror 501 _RE_ARGS ((int errcode, const regex_t *preg, char *errbuf, 502 size_t errbuf_size)); 503extern void regfree _RE_ARGS ((regex_t *preg)); 504 505#ifdef __cplusplus 506} 507#endif /* C++ */ 508 509#endif /* not __REGEXP_LIBRARY_H__ */ 510 511/* 512Local variables: 513make-backup-files: t 514version-control: t 515trim-versions-without-asking: nil 516End: 517*/ 518