lib/regex.h

   1 /* Definitions for data structures and routines for the regular
   2    expression library, version 0.12.
   3    Copyright (C) 1985,89,90,91,92,93,95,96,97,98 Free Software Foundation, Inc.
   4
   5    This file is part of the GNU C Library.  Its master source is NOT part of
   6    the C library, however.  The master source lives in /gd/gnu/lib.
   7
   8    The GNU C Library is free software; you can redistribute it and/or
   9    modify it under the terms of the GNU Library General Public License as
  10    published by the Free Software Foundation; either version 2 of the
  11    License, or (at your option) any later version.
  12
  13    The GNU C Library is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16    Library General Public License for more details.
  17
  18    You should have received a copy of the GNU Library General Public
  19    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  20    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  21    Boston, MA 02111-1307, USA.  */
  22
  23 #ifndef _REGEX_H
  24 #define _REGEX_H 1
  25
  26 /* Allow the use in C++ code.  */
  27 #ifdef __cplusplus
  28 extern "C" {
  29 #endif
  30
  31 /* POSIX says that <sys/types.h> must be included (by the caller) before
  32    <regex.h>.  */
  33
  34 #if !defined _POSIX_C_SOURCE && !defined _POSIX_SOURCE && defined VMS
  35 /* VMS doesn't have `size_t' in <sys/types.h>, even though POSIX says it
  36    should be there.  */
  37 # include <stddef.h>
  38 #endif
  39
  40 /* The following two types have to be signed and unsigned integer type
  41    wide enough to hold a value of a pointer.  For most ANSI compilers
  42    ptrdiff_t and size_t should be likely OK.  Still size of these two
  43    types is 2 for Microsoft C.  Ugh... */
  44 typedef long int s_reg_t;
  45 typedef unsigned long int active_reg_t;
  46
  47 /* The following bits are used to determine the regexp syntax we
  48    recognize.  The set/not-set meanings are chosen so that Emacs syntax
  49    remains the value 0.  The bits are given in alphabetical order, and
  50    the definitions shifted by one from the previous bit; thus, when we
  51    add or remove a bit, only one other definition need change.  */
  52 typedef unsigned long int reg_syntax_t;
  53
  54 /* If this bit is not set, then \ inside a bracket expression is literal.
  55    If set, then such a \ quotes the following character.  */
  56 #define RE_BACKSLASH_ESCAPE_IN_LISTS ((unsigned long int) 1)
  57
  58 /* If this bit is not set, then + and ? are operators, and \+ and \? are
  59      literals.
  60    If set, then \+ and \? are operators and + and ? are literals.  */
  61 #define RE_BK_PLUS_QM (RE_BACKSLASH_ESCAPE_IN_LISTS << 1)
  62
  63 /* If this bit is set, then character classes are supported.  They are:
  64      [:alpha:], [:upper:], [:lower:],  [:digit:], [:alnum:], [:xdigit:],
  65      [:space:], [:print:], [:punct:], [:graph:], and [:cntrl:].
  66    If not set, then character classes are not supported.  */
  67 #define RE_CHAR_CLASSES (RE_BK_PLUS_QM << 1)
  68
  69 /* If this bit is set, then ^ and $ are always anchors (outside bracket
  70      expressions, of course).
  71    If this bit is not set, then it depends:
  72         ^  is an anchor if it is at the beginning of a regular
  73            expression or after an open-group or an alternation operator;
  74         $  is an anchor if it is at the end of a regular expression, or
  75            before a close-group or an alternation operator.
  76
  77    This bit could be (re)combined with RE_CONTEXT_INDEP_OPS, because
  78    POSIX draft 11.2 says that * etc. in leading positions is undefined.
  79    We already implemented a previous draft which made those constructs
  80    invalid, though, so we haven't changed the code back.  */
  81 #define RE_CONTEXT_INDEP_ANCHORS (RE_CHAR_CLASSES << 1)
  82
  83 /* If this bit is set, then special characters are always special
  84      regardless of where they are in the pattern.
  85    If this bit is not set, then special characters are special only in
  86      some contexts; otherwise they are ordinary.  Specifically,
  87      * + ? and intervals are only special when not after the beginning,
  88      open-group, or alternation operator.  */
  89 #define RE_CONTEXT_INDEP_OPS (RE_CONTEXT_INDEP_ANCHORS << 1)
  90
  91 /* If this bit is set, then *, +, ?, and { cannot be first in an re or
  92      immediately after an alternation or begin-group operator.  */
  93 #define RE_CONTEXT_INVALID_OPS (RE_CONTEXT_INDEP_OPS << 1)
  94
  95 /* If this bit is set, then . matches newline.
  96    If not set, then it doesn't.  */
  97 #define RE_DOT_NEWLINE (RE_CONTEXT_INVALID_OPS << 1)
  98
  99 /* If this bit is set, then . doesn't match NUL.
 100    If not set, then it does.  */
 101 #define RE_DOT_NOT_NULL (RE_DOT_NEWLINE << 1)
 102
 103 /* If this bit is set, nonmatching lists [^...] do not match newline.
 104    If not set, they do.  */
 105 #define RE_HAT_LISTS_NOT_NEWLINE (RE_DOT_NOT_NULL << 1)
 106
 107 /* If this bit is set, either \{...\} or {...} defines an
 108      interval, depending on RE_NO_BK_BRACES.
 109    If not set, \{, \}, {, and } are literals.  */
 110 #define RE_INTERVALS (RE_HAT_LISTS_NOT_NEWLINE << 1)
 111
 112 /* If this bit is set, +, ? and | aren't recognized as operators.
 113    If not set, they are.  */
 114 #define RE_LIMITED_OPS (RE_INTERVALS << 1)
 115
 116 /* If this bit is set, newline is an alternation operator.
 117    If not set, newline is literal.  */
 118 #define RE_NEWLINE_ALT (RE_LIMITED_OPS << 1)
 119
 120 /* If this bit is set, then `{...}' defines an interval, and \{ and \}
 121      are literals.
 122   If not set, then `\{...\}' defines an interval.  */
 123 #define RE_NO_BK_BRACES (RE_NEWLINE_ALT << 1)
 124
 125 /* If this bit is set, (...) defines a group, and \( and \) are literals.
 126    If not set, \(...\) defines a group, and ( and ) are literals.  */
 127 #define RE_NO_BK_PARENS (RE_NO_BK_BRACES << 1)
 128
 129 /* If this bit is set, then \<digit> matches <digit>.
 130    If not set, then \<digit> is a back-reference.  */
 131 #define RE_NO_BK_REFS (RE_NO_BK_PARENS << 1)
 132
 133 /* If this bit is set, then | is an alternation operator, and \| is literal.
 134    If not set, then \| is an alternation operator, and | is literal.  */
 135 #define RE_NO_BK_VBAR (RE_NO_BK_REFS << 1)
 136
 137 /* If this bit is set, then an ending range point collating higher
 138      than the starting range point, as in [z-a], is invalid.
 139    If not set, then when ending range point collates higher than the
 140      starting range point, the range is ignored.  */
 141 #define RE_NO_EMPTY_RANGES (RE_NO_BK_VBAR << 1)
 142
 143 /* If this bit is set, then an unmatched ) is ordinary.
 144    If not set, then an unmatched ) is invalid.  */
 145 #define RE_UNMATCHED_RIGHT_PAREN_ORD (RE_NO_EMPTY_RANGES << 1)
 146
 147 /* If this bit is set, succeed as soon as we match the whole pattern,
 148    without further backtracking.  */
 149 #define RE_NO_POSIX_BACKTRACKING (RE_UNMATCHED_RIGHT_PAREN_ORD << 1)
 150
 151 /* If this bit is set, do not process the GNU regex operators.
 152    If not set, then the GNU regex operators are recognized. */
 153 #define RE_NO_GNU_OPS (RE_NO_POSIX_BACKTRACKING << 1)
 154
 155 /* If this bit is set, turn on internal regex debugging.
 156    If not set, and debugging was on, turn it off.
 157    This only works if regex.c is compiled -DDEBUG.
 158    We define this bit always, so that all that's needed to turn on
 159    debugging is to recompile regex.c; the calling code can always have
 160    this bit set, and it won't affect anything in the normal case. */
 161 #define RE_DEBUG (RE_NO_GNU_OPS << 1)
 162
 163 /* This global variable defines the particular regexp syntax to use (for
 164    some interfaces).  When a regexp is compiled, the syntax used is
 165    stored in the pattern buffer, so changing this does not affect
 166    already-compiled regexps.  */
 167 extern reg_syntax_t re_syntax_options;
 168 \f
 169 /* Define combinations of the above bits for the standard possibilities.
 170    (The [[[ comments delimit what gets put into the Texinfo file, so
 171    don't delete them!)  */
 172 /* [[[begin syntaxes]]] */
 173 #define RE_SYNTAX_EMACS 0
 174
 175 #define RE_SYNTAX_AWK                                                   \
 176   (RE_BACKSLASH_ESCAPE_IN_LISTS   | RE_DOT_NOT_NULL                     \
 177    | RE_NO_BK_PARENS              | RE_NO_BK_REFS                       \
 178    | RE_NO_BK_VBAR                | RE_NO_EMPTY_RANGES                  \
 179    | RE_DOT_NEWLINE               | RE_CONTEXT_INDEP_ANCHORS            \
 180    | RE_UNMATCHED_RIGHT_PAREN_ORD | RE_NO_GNU_OPS)
 181
 182 #define RE_SYNTAX_GNU_AWK                                               \
 183   ((RE_SYNTAX_POSIX_EXTENDED | RE_BACKSLASH_ESCAPE_IN_LISTS | RE_DEBUG) \
 184    & ~(RE_DOT_NOT_NULL | RE_INTERVALS | RE_CONTEXT_INDEP_OPS))
 185
 186 #define RE_SYNTAX_POSIX_AWK                                             \
 187   (RE_SYNTAX_POSIX_EXTENDED | RE_BACKSLASH_ESCAPE_IN_LISTS              \
 188    | RE_INTERVALS           | RE_NO_GNU_OPS)
 189
 190 #define RE_SYNTAX_GREP                                                  \
 191   (RE_BK_PLUS_QM              | RE_CHAR_CLASSES                         \
 192    | RE_HAT_LISTS_NOT_NEWLINE | RE_INTERVALS                            \
 193    | RE_NEWLINE_ALT)
 194
 195 #define RE_SYNTAX_EGREP                                                 \
 196   (RE_CHAR_CLASSES        | RE_CONTEXT_INDEP_ANCHORS                    \
 197    | RE_CONTEXT_INDEP_OPS | RE_HAT_LISTS_NOT_NEWLINE                    \
 198    | RE_NEWLINE_ALT       | RE_NO_BK_PARENS                             \
 199    | RE_NO_BK_VBAR)
 200
 201 #define RE_SYNTAX_POSIX_EGREP                                           \
 202   (RE_SYNTAX_EGREP | RE_INTERVALS | RE_NO_BK_BRACES)
 203
 204 /* P1003.2/D11.2, section 4.20.7.1, lines 5078ff.  */
 205 #define RE_SYNTAX_ED RE_SYNTAX_POSIX_BASIC
 206
 207 #define RE_SYNTAX_SED RE_SYNTAX_POSIX_BASIC
 208
 209 /* Syntax bits common to both basic and extended POSIX regex syntax.  */
 210 #define _RE_SYNTAX_POSIX_COMMON                                         \
 211   (RE_CHAR_CLASSES | RE_DOT_NEWLINE      | RE_DOT_NOT_NULL              \
 212    | RE_INTERVALS  | RE_NO_EMPTY_RANGES)
 213
 214 #define RE_SYNTAX_POSIX_BASIC                                           \
 215   (_RE_SYNTAX_POSIX_COMMON | RE_BK_PLUS_QM)
 216
 217 /* Differs from ..._POSIX_BASIC only in that RE_BK_PLUS_QM becomes
 218    RE_LIMITED_OPS, i.e., \? \+ \| are not recognized.  Actually, this
 219    isn't minimal, since other operators, such as \`, aren't disabled.  */
 220 #define RE_SYNTAX_POSIX_MINIMAL_BASIC                                   \
 221   (_RE_SYNTAX_POSIX_COMMON | RE_LIMITED_OPS)
 222
 223 #define RE_SYNTAX_POSIX_EXTENDED                                        \
 224   (_RE_SYNTAX_POSIX_COMMON | RE_CONTEXT_INDEP_ANCHORS                   \
 225    | RE_CONTEXT_INDEP_OPS  | RE_NO_BK_BRACES                            \
 226    | RE_NO_BK_PARENS       | RE_NO_BK_VBAR                              \
 227    | RE_UNMATCHED_RIGHT_PAREN_ORD)
 228
 229 /* Differs from ..._POSIX_EXTENDED in that RE_CONTEXT_INVALID_OPS
 230    replaces RE_CONTEXT_INDEP_OPS and RE_NO_BK_REFS is added.  */
 231 #define RE_SYNTAX_POSIX_MINIMAL_EXTENDED                                \
 232   (_RE_SYNTAX_POSIX_COMMON  | RE_CONTEXT_INDEP_ANCHORS                  \
 233    | RE_CONTEXT_INVALID_OPS | RE_NO_BK_BRACES                           \
 234    | RE_NO_BK_PARENS        | RE_NO_BK_REFS                             \
 235    | RE_NO_BK_VBAR          | RE_UNMATCHED_RIGHT_PAREN_ORD)
 236 /* [[[end syntaxes]]] */
 237 \f
 238 /* Maximum number of duplicates an interval can allow.  Some systems
 239    (erroneously) define this in other header files, but we want our
 240    value, so remove any previous define.  */
 241 #ifdef RE_DUP_MAX
 242 # undef RE_DUP_MAX
 243 #endif
 244 /* If sizeof(int) == 2, then ((1 << 15) - 1) overflows.  */
 245 #define RE_DUP_MAX (0x7fff)
 246
 247
 248 /* POSIX `cflags' bits (i.e., information for `regcomp').  */
 249
 250 /* If this bit is set, then use extended regular expression syntax.
 251    If not set, then use basic regular expression syntax.  */
 252 #define REG_EXTENDED 1
 253
 254 /* If this bit is set, then ignore case when matching.
 255    If not set, then case is significant.  */
 256 #define REG_ICASE (REG_EXTENDED << 1)
 257
 258 /* If this bit is set, then anchors do not match at newline
 259      characters in the string.
 260    If not set, then anchors do match at newlines.  */
 261 #define REG_NEWLINE (REG_ICASE << 1)
 262
 263 /* If this bit is set, then report only success or fail in regexec.
 264    If not set, then returns differ between not matching and errors.  */
 265 #define REG_NOSUB (REG_NEWLINE << 1)
 266
 267
 268 /* POSIX `eflags' bits (i.e., information for regexec).  */
 269
 270 /* If this bit is set, then the beginning-of-line operator doesn't match
 271      the beginning of the string (presumably because it's not the
 272      beginning of a line).
 273    If not set, then the beginning-of-line operator does match the
 274      beginning of the string.  */
 275 #define REG_NOTBOL 1
 276
 277 /* Like REG_NOTBOL, except for the end-of-line.  */
 278 #define REG_NOTEOL (1 << 1)
 279
 280
 281 /* If any error codes are removed, changed, or added, update the
 282    `re_error_msg' table in regex.c.  */
 283 typedef enum
 284 {
 285 #ifdef _XOPEN_SOURCE
 286   REG_ENOSYS = -1,      /* This will never happen for this implementation.  */
 287 #endif
 288
 289   REG_NOERROR = 0,      /* Success.  */
 290   REG_NOMATCH,          /* Didn't find a match (for regexec).  */
 291
 292   /* POSIX regcomp return error codes.  (In the order listed in the
 293      standard.)  */
 294   REG_BADPAT,           /* Invalid pattern.  */
 295   REG_ECOLLATE,         /* Not implemented.  */
 296   REG_ECTYPE,           /* Invalid character class name.  */
 297   REG_EESCAPE,          /* Trailing backslash.  */
 298   REG_ESUBREG,          /* Invalid back reference.  */
 299   REG_EBRACK,           /* Unmatched left bracket.  */
 300   REG_EPAREN,           /* Parenthesis imbalance.  */
 301   REG_EBRACE,           /* Unmatched \{.  */
 302   REG_BADBR,            /* Invalid contents of \{\}.  */
 303   REG_ERANGE,           /* Invalid range end.  */
 304   REG_ESPACE,           /* Ran out of memory.  */
 305   REG_BADRPT,           /* No preceding re for repetition op.  */
 306
 307   /* Error codes we've added.  */
 308   REG_EEND,             /* Premature end.  */
 309   REG_ESIZE,            /* Compiled pattern bigger than 2^16 bytes.  */
 310   REG_ERPAREN           /* Unmatched ) or \); not returned from regcomp.  */
 311 } reg_errcode_t;
 312 \f
 313 /* This data structure represents a compiled pattern.  Before calling
 314    the pattern compiler, the fields `buffer', `allocated', `fastmap',
 315    `translate', and `no_sub' can be set.  After the pattern has been
 316    compiled, the `re_nsub' field is available.  All other fields are
 317    private to the regex routines.  */
 318
 319 #ifndef RE_TRANSLATE_TYPE
 320 # define RE_TRANSLATE_TYPE char *
 321 #endif
 322
 323 struct re_pattern_buffer
 324 {
 325 /* [[[begin pattern_buffer]]] */
 326         /* Space that holds the compiled pattern.  It is declared as
 327           `unsigned char *' because its elements are
 328            sometimes used as array indexes.  */
 329   unsigned char *buffer;
 330
 331         /* Number of bytes to which `buffer' points.  */
 332   unsigned long int allocated;
 333
 334         /* Number of bytes actually used in `buffer'.  */
 335   unsigned long int used;
 336
 337         /* Syntax setting with which the pattern was compiled.  */
 338   reg_syntax_t syntax;
 339
 340         /* Pointer to a fastmap, if any, otherwise zero.  re_search uses
 341            the fastmap, if there is one, to skip over impossible
 342            starting points for matches.  */
 343   char *fastmap;
 344
 345         /* Either a translate table to apply to all characters before
 346            comparing them, or zero for no translation.  The translation
 347            is applied to a pattern when it is compiled and to a string
 348            when it is matched.  */
 349   RE_TRANSLATE_TYPE translate;
 350
 351         /* Number of subexpressions found by the compiler.  */
 352   size_t re_nsub;
 353
 354         /* Zero if this pattern cannot match the empty string, one else.
 355            Well, in truth it's used only in `re_search_2', to see
 356            whether or not we should use the fastmap, so we don't set
 357            this absolutely perfectly; see `re_compile_fastmap' (the
 358            `duplicate' case).  */
 359   unsigned can_be_null : 1;
 360
 361         /* If REGS_UNALLOCATED, allocate space in the `regs' structure
 362              for `max (RE_NREGS, re_nsub + 1)' groups.
 363            If REGS_REALLOCATE, reallocate space if necessary.
 364            If REGS_FIXED, use what's there.  */
 365 #define REGS_UNALLOCATED 0
 366 #define REGS_REALLOCATE 1
 367 #define REGS_FIXED 2
 368   unsigned regs_allocated : 2;
 369
 370         /* Set to zero when `regex_compile' compiles a pattern; set to one
 371            by `re_compile_fastmap' if it updates the fastmap.  */
 372   unsigned fastmap_accurate : 1;
 373
 374         /* If set, `re_match_2' does not return information about
 375            subexpressions.  */
 376   unsigned no_sub : 1;
 377
 378         /* If set, a beginning-of-line anchor doesn't match at the
 379            beginning of the string.  */
 380   unsigned not_bol : 1;
 381
 382         /* Similarly for an end-of-line anchor.  */
 383   unsigned not_eol : 1;
 384
 385         /* If true, an anchor at a newline matches.  */
 386   unsigned newline_anchor : 1;
 387
 388 /* [[[end pattern_buffer]]] */
 389 };
 390
 391 typedef struct re_pattern_buffer regex_t;
 392 \f
 393 /* Type for byte offsets within the string.  POSIX mandates this.  */
 394 typedef int regoff_t;
 395
 396
 397 /* This is the structure we store register match data in.  See
 398    regex.texinfo for a full description of what registers match.  */
 399 struct re_registers
 400 {
 401   unsigned num_regs;
 402   regoff_t *start;
 403   regoff_t *end;
 404 };
 405
 406
 407 /* If `regs_allocated' is REGS_UNALLOCATED in the pattern buffer,
 408    `re_match_2' returns information about at least this many registers
 409    the first time a `regs' structure is passed.  */
 410 #ifndef RE_NREGS
 411 # define RE_NREGS 30
 412 #endif
 413
 414
 415 /* POSIX specification for registers.  Aside from the different names than
 416    `re_registers', POSIX uses an array of structures, instead of a
 417    structure of arrays.  */
 418 typedef struct
 419 {
 420   regoff_t rm_so;  /* Byte offset from string's start to substring's start.  */
 421   regoff_t rm_eo;  /* Byte offset from string's start to substring's end.  */
 422 } regmatch_t;
 423 \f
 424 /* Declarations for routines.  */
 425
 426 /* To avoid duplicating every routine declaration -- once with a
 427    prototype (if we are ANSI), and once without (if we aren't) -- we
 428    use the following macro to declare argument types.  This
 429    unfortunately clutters up the declarations a bit, but I think it's
 430    worth it.  */
 431
 432 #if __STDC__
 433
 434 # define _RE_ARGS(args) args
 435
 436 #else /* not __STDC__ */
 437
 438 # define _RE_ARGS(args) ()
 439
 440 #endif /* not __STDC__ */
 441
 442 /* Sets the current default syntax to SYNTAX, and return the old syntax.
 443    You can also simply assign to the `re_syntax_options' variable.  */
 444 extern reg_syntax_t re_set_syntax _RE_ARGS ((reg_syntax_t syntax));
 445
 446 /* Compile the regular expression PATTERN, with length LENGTH
 447    and syntax given by the global `re_syntax_options', into the buffer
 448    BUFFER.  Return NULL if successful, and an error string if not.  */
 449 extern const char *re_compile_pattern
 450   _RE_ARGS ((const char *pattern, size_t length,
 451              struct re_pattern_buffer *buffer));
 452
 453
 454 /* Compile a fastmap for the compiled pattern in BUFFER; used to
 455    accelerate searches.  Return 0 if successful and -2 if was an
 456    internal error.  */
 457 extern int re_compile_fastmap _RE_ARGS ((struct re_pattern_buffer *buffer));
 458
 459
 460 /* Search in the string STRING (with length LENGTH) for the pattern
 461    compiled into BUFFER.  Start searching at position START, for RANGE
 462    characters.  Return the starting position of the match, -1 for no
 463    match, or -2 for an internal error.  Also return register
 464    information in REGS (if REGS and BUFFER->no_sub are nonzero).  */
 465 extern int re_search
 466   _RE_ARGS ((struct re_pattern_buffer *buffer, const char *string,
 467             int length, int start, int range, struct re_registers *regs));
 468
 469
 470 /* Like `re_search', but search in the concatenation of STRING1 and
 471    STRING2.  Also, stop searching at index START + STOP.  */
 472 extern int re_search_2
 473   _RE_ARGS ((struct re_pattern_buffer *buffer, const char *string1,
 474              int length1, const char *string2, int length2,
 475              int start, int range, struct re_registers *regs, int stop));
 476
 477
 478 /* Like `re_search', but return how many characters in STRING the regexp
 479    in BUFFER matched, starting at position START.  */
 480 extern int re_match
 481   _RE_ARGS ((struct re_pattern_buffer *buffer, const char *string,
 482              int length, int start, struct re_registers *regs));
 483
 484
 485 /* Relates to `re_match' as `re_search_2' relates to `re_search'.  */
 486 extern int re_match_2
 487   _RE_ARGS ((struct re_pattern_buffer *buffer, const char *string1,
 488              int length1, const char *string2, int length2,
 489              int start, struct re_registers *regs, int stop));
 490
 491
 492 /* Set REGS to hold NUM_REGS registers, storing them in STARTS and
 493    ENDS.  Subsequent matches using BUFFER and REGS will use this memory
 494    for recording register information.  STARTS and ENDS must be
 495    allocated with malloc, and must each be at least `NUM_REGS * sizeof
 496    (regoff_t)' bytes long.
 497
 498    If NUM_REGS == 0, then subsequent matches should allocate their own
 499    register data.
 500
 501    Unless this function is called, the first search or match using
 502    PATTERN_BUFFER will allocate its own register data, without
 503    freeing the old data.  */
 504 extern void re_set_registers
 505   _RE_ARGS ((struct re_pattern_buffer *buffer, struct re_registers *regs,
 506              unsigned num_regs, regoff_t *starts, regoff_t *ends));
 507
 508 #if defined _REGEX_RE_COMP || defined _LIBC
 509 # ifndef _CRAY
 510 /* 4.2 bsd compatibility.  */
 511 extern char *re_comp _RE_ARGS ((const char *));
 512 extern int re_exec _RE_ARGS ((const char *));
 513 # endif
 514 #endif
 515
 516 /* POSIX compatibility.  */
 517 extern int regcomp _RE_ARGS ((regex_t *__preg, const char *__pattern,
 518                               int __cflags));
 519
 520 extern int regexec _RE_ARGS ((const regex_t *__preg,
 521                               const char *__string, size_t __nmatch,
 522                               regmatch_t __pmatch[], int __eflags));
 523
 524 extern size_t regerror _RE_ARGS ((int __errcode, const regex_t *__preg,
 525                                   char *__errbuf, size_t __errbuf_size));
 526
 527 extern void regfree _RE_ARGS ((regex_t *__preg));
 528
 529
 530 #ifdef __cplusplus
 531 }
 532 #endif  /* C++ */
 533
 534 #endif /* regex.h */
 535 \f
 536 /*
 537 Local variables:
 538 make-backup-files: t
 539 version-control: t
 540 trim-versions-without-asking: nil
 541 End:
 542 */