src/vms/regex.h

/* Definitions for data structures and routines for the regular
   expression library, version 0.12.

   Copyright (C) 1985, 1989, 1990, 1991, 1992, 1993 Free Software Foundation, Inc.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2, or (at your option)
   any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */

#ifndef __REGEXP_LIBRARY_H__
#define __REGEXP_LIBRARY_H__

/* POSIX says that <sys/types.h> must be included (by the caller) before
   <regex.h>.  */

#ifdef VMS
/* VMS doesn't have `size_t' in <sys/types.h>, even though POSIX says it
   should be there.  */
#include <stddef.h>
#endif


/* The following bits are used to determine the regexp syntax we
   recognize.  The set/not-set meanings are chosen so that Emacs syntax
   remains the value 0.  The bits are given in alphabetical order, and
   the definitions shifted by one from the previous bit; thus, when we
   add or remove a bit, only one other definition need change.  */
typedef unsigned reg_syntax_t;

/* If this bit is not set, then \ inside a bracket expression is literal.
   If set, then such a \ quotes the following character.  */
#define RE_BACKSLASH_ESCAPE_IN_LISTS (1)

/* If this bit is not set, then + and ? are operators, and \+ and \? are
     literals. 
   If set, then \+ and \? are operators and + and ? are literals.  */
#define RE_BK_PLUS_QM (RE_BACKSLASH_ESCAPE_IN_LISTS << 1)

/* If this bit is set, then character classes are supported.  They are:
     [:alpha:], [:upper:], [:lower:],  [:digit:], [:alnum:], [:xdigit:],
     [:space:], [:print:], [:punct:], [:graph:], and [:cntrl:].
   If not set, then character classes are not supported.  */
#define RE_CHAR_CLASSES (RE_BK_PLUS_QM << 1)

/* If this bit is set, then ^ and $ are always anchors (outside bracket
     expressions, of course).
   If this bit is not set, then it depends:
        ^  is an anchor if it is at the beginning of a regular
           expression or after an open-group or an alternation operator;
        $  is an anchor if it is at the end of a regular expression, or
           before a close-group or an alternation operator.  

   This bit could be (re)combined with RE_CONTEXT_INDEP_OPS, because
   POSIX draft 11.2 says that * etc. in leading positions is undefined.
   We already implemented a previous draft which made those constructs
   invalid, though, so we haven't changed the code back.  */
#define RE_CONTEXT_INDEP_ANCHORS (RE_CHAR_CLASSES << 1)

/* If this bit is set, then special characters are always special
     regardless of where they are in the pattern.
   If this bit is not set, then special characters are special only in
     some contexts; otherwise they are ordinary.  Specifically, 
     * + ? and intervals are only special when not after the beginning,
     open-group, or alternation operator.  */
#define RE_CONTEXT_INDEP_OPS (RE_CONTEXT_INDEP_ANCHORS << 1)

/* If this bit is set, then *, +, ?, and { cannot be first in an re or
     immediately after an alternation or begin-group operator.  */
#define RE_CONTEXT_INVALID_OPS (RE_CONTEXT_INDEP_OPS << 1)

/* If this bit is set, then . matches newline.
   If not set, then it doesn't.  */
#define RE_DOT_NEWLINE (RE_CONTEXT_INVALID_OPS << 1)

/* If this bit is set, then . doesn't match NUL.
   If not set, then it does.  */
#define RE_DOT_NOT_NULL (RE_DOT_NEWLINE << 1)

/* If this bit is set, nonmatching lists [^...] do not match newline.
   If not set, they do.  */
#define RE_HAT_LISTS_NOT_NEWLINE (RE_DOT_NOT_NULL << 1)

/* If this bit is set, either \{...\} or {...} defines an
     interval, depending on RE_NO_BK_BRACES. 
   If not set, \{, \}, {, and } are literals.  */
#define RE_INTERVALS (RE_HAT_LISTS_NOT_NEWLINE << 1)

/* If this bit is set, +, ? and | aren't recognized as operators.
   If not set, they are.  */
#define RE_LIMITED_OPS (RE_INTERVALS << 1)

/* If this bit is set, newline is an alternation operator.
   If not set, newline is literal.  */
#define RE_NEWLINE_ALT (RE_LIMITED_OPS << 1)

/* If this bit is set, then `{...}' defines an interval, and \{ and \}
     are literals.
  If not set, then `\{...\}' defines an interval.  */
#define RE_NO_BK_BRACES (RE_NEWLINE_ALT << 1)

/* If this bit is set, (...) defines a group, and \( and \) are literals.
   If not set, \(...\) defines a group, and ( and ) are literals.  */
#define RE_NO_BK_PARENS (RE_NO_BK_BRACES << 1)

/* If this bit is set, then \<digit> matches <digit>.
   If not set, then \<digit> is a back-reference.  */
#define RE_NO_BK_REFS (RE_NO_BK_PARENS << 1)

/* If this bit is set, then | is an alternation operator, and \| is literal. 
   If not set, then \| is an alternation operator, and | is literal.  */
#define RE_NO_BK_VBAR (RE_NO_BK_REFS << 1)

/* If this bit is set, then an ending range point collating higher
     than the starting range point, as in [z-a], is invalid.
   If not set, then when ending range point collates higher than the
     starting range point, the range is ignored.  */
#define RE_NO_EMPTY_RANGES (RE_NO_BK_VBAR << 1)

/* If this bit is set, then an unmatched ) is ordinary.
   If not set, then an unmatched ) is invalid.  */
#define RE_UNMATCHED_RIGHT_PAREN_ORD (RE_NO_EMPTY_RANGES << 1)

/* This global variable defines the particular regexp syntax to use (for
   some interfaces).  When a regexp is compiled, the syntax used is
   stored in the pattern buffer, so changing this does not affect
   already-compiled regexps.  */
extern reg_syntax_t re_syntax_options;

/* Define combinations of the above bits for the standard possibilities.
   (The [[[ comments delimit what gets put into the Texinfo file, so
   don't delete them!)  */ 
/* [[[begin syntaxes]]] */
#define RE_SYNTAX_EMACS 0

#define RE_SYNTAX_AWK                                                   \
  (RE_BACKSLASH_ESCAPE_IN_LISTS | RE_DOT_NOT_NULL                       \
   | RE_NO_BK_PARENS            | RE_NO_BK_REFS                         \
   | RE_NO_BK_VBAR               | RE_NO_EMPTY_RANGES                   \
   | RE_UNMATCHED_RIGHT_PAREN_ORD)

#define RE_SYNTAX_POSIX_AWK                                             \
  (RE_SYNTAX_POSIX_EXTENDED | RE_BACKSLASH_ESCAPE_IN_LISTS)

#define RE_SYNTAX_GREP                                                  \
  (RE_BK_PLUS_QM              | RE_CHAR_CLASSES                         \
   | RE_HAT_LISTS_NOT_NEWLINE | RE_INTERVALS                            \
   | RE_NEWLINE_ALT)

#define RE_SYNTAX_EGREP                                                 \
  (RE_CHAR_CLASSES        | RE_CONTEXT_INDEP_ANCHORS                    \
   | RE_CONTEXT_INDEP_OPS | RE_HAT_LISTS_NOT_NEWLINE                    \
   | RE_NEWLINE_ALT       | RE_NO_BK_PARENS                             \
   | RE_NO_BK_VBAR)

#define RE_SYNTAX_POSIX_EGREP                                           \
  (RE_SYNTAX_EGREP | RE_INTERVALS | RE_NO_BK_BRACES)

/* P1003.2/D11.2, section 4.20.7.1, lines 5078ff.  */
#define RE_SYNTAX_ED RE_SYNTAX_POSIX_BASIC

#define RE_SYNTAX_SED RE_SYNTAX_POSIX_BASIC

/* Syntax bits common to both basic and extended POSIX regex syntax.  */
#define _RE_SYNTAX_POSIX_COMMON                                         \
  (RE_CHAR_CLASSES | RE_DOT_NEWLINE      | RE_DOT_NOT_NULL              \
   | RE_INTERVALS  | RE_NO_EMPTY_RANGES)

#define RE_SYNTAX_POSIX_BASIC                                           \
  (_RE_SYNTAX_POSIX_COMMON | RE_BK_PLUS_QM)

/* Differs from ..._POSIX_BASIC only in that RE_BK_PLUS_QM becomes
   RE_LIMITED_OPS, i.e., \? \+ \| are not recognized.  Actually, this
   isn't minimal, since other operators, such as \`, aren't disabled.  */
#define RE_SYNTAX_POSIX_MINIMAL_BASIC                                   \
  (_RE_SYNTAX_POSIX_COMMON | RE_LIMITED_OPS)

#define RE_SYNTAX_POSIX_EXTENDED                                        \
  (_RE_SYNTAX_POSIX_COMMON | RE_CONTEXT_INDEP_ANCHORS                   \
   | RE_CONTEXT_INDEP_OPS  | RE_NO_BK_BRACES                            \
   | RE_NO_BK_PARENS       | RE_NO_BK_VBAR                              \
   | RE_UNMATCHED_RIGHT_PAREN_ORD)

/* Differs from ..._POSIX_EXTENDED in that RE_CONTEXT_INVALID_OPS
   replaces RE_CONTEXT_INDEP_OPS and RE_NO_BK_REFS is added.  */
#define RE_SYNTAX_POSIX_MINIMAL_EXTENDED                                \
  (_RE_SYNTAX_POSIX_COMMON  | RE_CONTEXT_INDEP_ANCHORS                  \
   | RE_CONTEXT_INVALID_OPS | RE_NO_BK_BRACES                           \
   | RE_NO_BK_PARENS        | RE_NO_BK_REFS                             \
   | RE_NO_BK_VBAR          | RE_UNMATCHED_RIGHT_PAREN_ORD)
/* [[[end syntaxes]]] */

/* Maximum number of duplicates an interval can allow.  Some systems
   (erroneously) define this in other header files, but we want our
   value, so remove any previous define.  */
#ifdef RE_DUP_MAX
#undef RE_DUP_MAX
#endif
#define RE_DUP_MAX ((1 << 15) - 1) 


/* POSIX `cflags' bits (i.e., information for `regcomp').  */

/* If this bit is set, then use extended regular expression syntax.
   If not set, then use basic regular expression syntax.  */
#define REG_EXTENDED 1

/* If this bit is set, then ignore case when matching.
   If not set, then case is significant.  */
#define REG_ICASE (REG_EXTENDED << 1)
 
/* If this bit is set, then anchors do not match at newline
     characters in the string.
   If not set, then anchors do match at newlines.  */
#define REG_NEWLINE (REG_ICASE << 1)

/* If this bit is set, then report only success or fail in regexec.
   If not set, then returns differ between not matching and errors.  */
#define REG_NOSUB (REG_NEWLINE << 1)


/* POSIX `eflags' bits (i.e., information for regexec).  */

/* If this bit is set, then the beginning-of-line operator doesn't match
     the beginning of the string (presumably because it's not the
     beginning of a line).
   If not set, then the beginning-of-line operator does match the
     beginning of the string.  */
#define REG_NOTBOL 1

/* Like REG_NOTBOL, except for the end-of-line.  */
#define REG_NOTEOL (1 << 1)


/* If any error codes are removed, changed, or added, update the
   `re_error_msg' table in regex.c.  */
typedef enum
{
  REG_NOERROR = 0,      /* Success.  */
  REG_NOMATCH,          /* Didn't find a match (for regexec).  */

  /* POSIX regcomp return error codes.  (In the order listed in the
     standard.)  */
  REG_BADPAT,           /* Invalid pattern.  */
  REG_ECOLLATE,         /* Not implemented.  */
  REG_ECTYPE,           /* Invalid character class name.  */
  REG_EESCAPE,          /* Trailing backslash.  */
  REG_ESUBREG,          /* Invalid back reference.  */
  REG_EBRACK,           /* Unmatched left bracket.  */
  REG_EPAREN,           /* Parenthesis imbalance.  */ 
  REG_EBRACE,           /* Unmatched \{.  */
  REG_BADBR,            /* Invalid contents of \{\}.  */
  REG_ERANGE,           /* Invalid range end.  */
  REG_ESPACE,           /* Ran out of memory.  */
  REG_BADRPT,           /* No preceding re for repetition op.  */

  /* Error codes we've added.  */
  REG_EEND,             /* Premature end.  */
  REG_ESIZE,            /* Compiled pattern bigger than 2^16 bytes.  */
  REG_ERPAREN           /* Unmatched ) or \); not returned from regcomp.  */
} reg_errcode_t;

/* This data structure represents a compiled pattern.  Before calling
   the pattern compiler, the fields `buffer', `allocated', `fastmap',
   `translate', and `no_sub' can be set.  After the pattern has been
   compiled, the `re_nsub' field is available.  All other fields are
   private to the regex routines.  */

struct re_pattern_buffer
{
/* [[[begin pattern_buffer]]] */
        /* Space that holds the compiled pattern.  It is declared as
          `unsigned char *' because its elements are
           sometimes used as array indexes.  */
  unsigned char *buffer;

        /* Number of bytes to which `buffer' points.  */
  unsigned long allocated;

        /* Number of bytes actually used in `buffer'.  */
  unsigned long used;   

        /* Syntax setting with which the pattern was compiled.  */
  reg_syntax_t syntax;

        /* Pointer to a fastmap, if any, otherwise zero.  re_search uses
           the fastmap, if there is one, to skip over impossible
           starting points for matches.  */
  char *fastmap;

        /* Either a translate table to apply to all characters before
           comparing them, or zero for no translation.  The translation
           is applied to a pattern when it is compiled and to a string
           when it is matched.  */
  char *translate;

        /* Number of subexpressions found by the compiler.  */
  size_t re_nsub;

        /* Zero if this pattern cannot match the empty string, one else.
           Well, in truth it's used only in `re_search_2', to see
           whether or not we should use the fastmap, so we don't set
           this absolutely perfectly; see `re_compile_fastmap' (the
           `duplicate' case).  */
  unsigned can_be_null : 1;

        /* If REGS_UNALLOCATED, allocate space in the `regs' structure
             for `max (RE_NREGS, re_nsub + 1)' groups.
           If REGS_REALLOCATE, reallocate space if necessary.
           If REGS_FIXED, use what's there.  */
#define REGS_UNALLOCATED 0
#define REGS_REALLOCATE 1
#define REGS_FIXED 2
  unsigned regs_allocated : 2;

        /* Set to zero when `regex_compile' compiles a pattern; set to one
           by `re_compile_fastmap' if it updates the fastmap.  */
  unsigned fastmap_accurate : 1;

        /* If set, `re_match_2' does not return information about
           subexpressions.  */
  unsigned no_sub : 1;

        /* If set, a beginning-of-line anchor doesn't match at the
           beginning of the string.  */ 
  unsigned not_bol : 1;

        /* Similarly for an end-of-line anchor.  */
  unsigned not_eol : 1;

        /* If true, an anchor at a newline matches.  */
  unsigned newline_anchor : 1;

/* [[[end pattern_buffer]]] */
};

typedef struct re_pattern_buffer regex_t;


/* search.c (search_buffer) in Emacs needs this one opcode value.  It is
   defined both in `regex.c' and here.  */
#define RE_EXACTN_VALUE 1

/* Type for byte offsets within the string.  POSIX mandates this.  */
typedef int regoff_t;


/* This is the structure we store register match data in.  See
   regex.texinfo for a full description of what registers match.  */
struct re_registers
{
  unsigned num_regs;
  regoff_t *start;
  regoff_t *end;
};


/* If `regs_allocated' is REGS_UNALLOCATED in the pattern buffer,
   `re_match_2' returns information about at least this many registers
   the first time a `regs' structure is passed.  */
#ifndef RE_NREGS
#define RE_NREGS 30
#endif


/* POSIX specification for registers.  Aside from the different names than
   `re_registers', POSIX uses an array of structures, instead of a
   structure of arrays.  */
typedef struct
{
  regoff_t rm_so;  /* Byte offset from string's start to substring's start.  */
  regoff_t rm_eo;  /* Byte offset from string's start to substring's end.  */
} regmatch_t;

/* Declarations for routines.  */

/* To avoid duplicating every routine declaration -- once with a
   prototype (if we are ANSI), and once without (if we aren't) -- we
   use the following macro to declare argument types.  This
   unfortunately clutters up the declarations a bit, but I think it's
   worth it.  */

#if __STDC__

#define _RE_ARGS(args) args

#else /* not __STDC__ */

#define _RE_ARGS(args) ()

#endif /* not __STDC__ */

/* Sets the current default syntax to SYNTAX, and return the old syntax.
   You can also simply assign to the `re_syntax_options' variable.  */
extern reg_syntax_t re_set_syntax _RE_ARGS ((reg_syntax_t syntax));

/* Compile the regular expression PATTERN, with length LENGTH
   and syntax given by the global `re_syntax_options', into the buffer
   BUFFER.  Return NULL if successful, and an error string if not.  */
extern const char *re_compile_pattern
  _RE_ARGS ((const char *pattern, int length,
             struct re_pattern_buffer *buffer));


/* Compile a fastmap for the compiled pattern in BUFFER; used to
   accelerate searches.  Return 0 if successful and -2 if was an
   internal error.  */
extern int re_compile_fastmap _RE_ARGS ((struct re_pattern_buffer *buffer));


/* Search in the string STRING (with length LENGTH) for the pattern
   compiled into BUFFER.  Start searching at position START, for RANGE
   characters.  Return the starting position of the match, -1 for no
   match, or -2 for an internal error.  Also return register
   information in REGS (if REGS and BUFFER->no_sub are nonzero).  */
extern int re_search
  _RE_ARGS ((struct re_pattern_buffer *buffer, const char *string,
            int length, int start, int range, struct re_registers *regs));


/* Like `re_search', but search in the concatenation of STRING1 and
   STRING2.  Also, stop searching at index START + STOP.  */
extern int re_search_2
  _RE_ARGS ((struct re_pattern_buffer *buffer, const char *string1,
             int length1, const char *string2, int length2,
             int start, int range, struct re_registers *regs, int stop));


/* Like `re_search', but return how many characters in STRING the regexp
   in BUFFER matched, starting at position START.  */
extern int re_match
  _RE_ARGS ((struct re_pattern_buffer *buffer, const char *string,
             int length, int start, struct re_registers *regs));


/* Relates to `re_match' as `re_search_2' relates to `re_search'.  */
extern int re_match_2 
  _RE_ARGS ((struct re_pattern_buffer *buffer, const char *string1,
             int length1, const char *string2, int length2,
             int start, struct re_registers *regs, int stop));


/* Set REGS to hold NUM_REGS registers, storing them in STARTS and
   ENDS.  Subsequent matches using BUFFER and REGS will use this memory
   for recording register information.  STARTS and ENDS must be
   allocated with malloc, and must each be at least `NUM_REGS * sizeof
   (regoff_t)' bytes long.

   If NUM_REGS == 0, then subsequent matches should allocate their own
   register data.

   Unless this function is called, the first search or match using
   PATTERN_BUFFER will allocate its own register data, without
   freeing the old data.  */
extern void re_set_registers
  _RE_ARGS ((struct re_pattern_buffer *buffer, struct re_registers *regs,
             unsigned num_regs, regoff_t *starts, regoff_t *ends));

/* 4.2 bsd compatibility.  */
extern char *re_comp _RE_ARGS ((const char *));
extern int re_exec _RE_ARGS ((const char *));

/* POSIX compatibility.  */
extern int regcomp _RE_ARGS ((regex_t *preg, const char *pattern, int cflags));
extern int regexec
  _RE_ARGS ((const regex_t *preg, const char *string, size_t nmatch,
             regmatch_t pmatch[], int eflags));
extern size_t regerror
  _RE_ARGS ((int errcode, const regex_t *preg, char *errbuf,
             size_t errbuf_size));
extern void regfree _RE_ARGS ((regex_t *preg));

#endif /* not __REGEXP_LIBRARY_H__ */

/*
Local variables:
make-backup-files: t
version-control: t
trim-versions-without-asking: nil
End:
*/
1	adcroft	1.1	/* 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			/* Sets the current default syntax to SYNTAX, and return the old syntax.
403			You can also simply assign to the `re_syntax_options' variable. */
404			extern reg_syntax_t re_set_syntax _RE_ARGS ((reg_syntax_t syntax));
405
406			/* Compile the regular expression PATTERN, with length LENGTH
407			and syntax given by the global `re_syntax_options', into the buffer
408			BUFFER. Return NULL if successful, and an error string if not. */
409			extern const char *re_compile_pattern
410			_RE_ARGS ((const char *pattern, int length,
411			struct re_pattern_buffer *buffer));
412
413
414			/* Compile a fastmap for the compiled pattern in BUFFER; used to
415			accelerate searches. Return 0 if successful and -2 if was an
416			internal error. */
417			extern int re_compile_fastmap _RE_ARGS ((struct re_pattern_buffer *buffer));
418
419
420			/* Search in the string STRING (with length LENGTH) for the pattern
421			compiled into BUFFER. Start searching at position START, for RANGE
422			characters. Return the starting position of the match, -1 for no
423			match, or -2 for an internal error. Also return register
424			information in REGS (if REGS and BUFFER->no_sub are nonzero). */
425			extern int re_search
426			_RE_ARGS ((struct re_pattern_buffer buffer, const char string,
427			int length, int start, int range, struct re_registers *regs));
428
429
430			/* Like `re_search', but search in the concatenation of STRING1 and
431			STRING2. Also, stop searching at index START + STOP. */
432			extern int re_search_2
433			_RE_ARGS ((struct re_pattern_buffer buffer, const char string1,
434			int length1, const char *string2, int length2,
435			int start, int range, struct re_registers *regs, int stop));
436
437
438			/* Like `re_search', but return how many characters in STRING the regexp
439			in BUFFER matched, starting at position START. */
440			extern int re_match
441			_RE_ARGS ((struct re_pattern_buffer buffer, const char string,
442			int length, int start, struct re_registers *regs));
443
444
445			/* Relates to `re_match' as `re_search_2' relates to `re_search'. */
446			extern int re_match_2
447			_RE_ARGS ((struct re_pattern_buffer buffer, const char string1,
448			int length1, const char *string2, int length2,
449			int start, struct re_registers *regs, int stop));
450
451
452			/* Set REGS to hold NUM_REGS registers, storing them in STARTS and
453			ENDS. Subsequent matches using BUFFER and REGS will use this memory
454			for recording register information. STARTS and ENDS must be
455			allocated with malloc, and must each be at least `NUM_REGS * sizeof
456			(regoff_t)' bytes long.
457
458			If NUM_REGS == 0, then subsequent matches should allocate their own
459			register data.
460
461			Unless this function is called, the first search or match using
462			PATTERN_BUFFER will allocate its own register data, without
463			freeing the old data. */
464			extern void re_set_registers
465			_RE_ARGS ((struct re_pattern_buffer buffer, struct re_registers regs,
466			unsigned num_regs, regoff_t starts, regoff_t ends));
467
468			/* 4.2 bsd compatibility. */
469			extern char re_comp _RE_ARGS ((const char ));
470			extern int re_exec _RE_ARGS ((const char *));
471
472			/* POSIX compatibility. */
473			extern int regcomp _RE_ARGS ((regex_t preg, const char pattern, int cflags));
474			extern int regexec
475			_RE_ARGS ((const regex_t preg, const char string, size_t nmatch,
476			regmatch_t pmatch[], int eflags));
477			extern size_t regerror
478			_RE_ARGS ((int errcode, const regex_t preg, char errbuf,
479			size_t errbuf_size));
480			extern void regfree _RE_ARGS ((regex_t *preg));
481
482			#endif /* not __REGEXP_LIBRARY_H__ */
483
484			/*
485			Local variables:
486			make-backup-files: t
487			version-control: t
488			trim-versions-without-asking: nil
489			End:
490			*/