559 lines
22 KiB
C++
559 lines
22 KiB
C++
/* dfa.h - declarations for GNU deterministic regexp compiler
|
||
Copyright (C) 1988 Free Software Foundation, Inc.
|
||
Written June, 1988 by Mike Haertel
|
||
|
||
NO WARRANTY
|
||
|
||
BECAUSE THIS PROGRAM IS LICENSED FREE OF CHARGE, WE PROVIDE ABSOLUTELY
|
||
NO WARRANTY, TO THE EXTENT PERMITTED BY APPLICABLE STATE LAW. EXCEPT
|
||
WHEN OTHERWISE STATED IN WRITING, FREE SOFTWARE FOUNDATION, INC,
|
||
RICHARD M. STALLMAN AND/OR OTHER PARTIES PROVIDE THIS PROGRAM "AS IS"
|
||
WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
|
||
BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
|
||
FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY
|
||
AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE
|
||
DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR
|
||
CORRECTION.
|
||
|
||
IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW WILL RICHARD M.
|
||
STALLMAN, THE FREE SOFTWARE FOUNDATION, INC., AND/OR ANY OTHER PARTY
|
||
WHO MAY MODIFY AND REDISTRIBUTE THIS PROGRAM AS PERMITTED BELOW, BE
|
||
LIABLE TO YOU FOR DAMAGES, INCLUDING ANY LOST PROFITS, LOST MONIES, OR
|
||
OTHER SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
|
||
USE OR INABILITY TO USE (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR
|
||
DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY THIRD PARTIES OR
|
||
A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS) THIS
|
||
PROGRAM, EVEN IF YOU HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH
|
||
DAMAGES, OR FOR ANY CLAIM BY ANY OTHER PARTY.
|
||
|
||
GENERAL PUBLIC LICENSE TO COPY
|
||
|
||
1. You may copy and distribute verbatim copies of this source file
|
||
as you receive it, in any medium, provided that you conspicuously and
|
||
appropriately publish on each copy a valid copyright notice "Copyright
|
||
(C) 1988 Free Software Foundation, Inc."; and include following the
|
||
copyright notice a verbatim copy of the above disclaimer of warranty
|
||
and of this License. You may charge a distribution fee for the
|
||
physical act of transferring a copy.
|
||
|
||
2. You may modify your copy or copies of this source file or
|
||
any portion of it, and copy and distribute such modifications under
|
||
the terms of Paragraph 1 above, provided that you also do the following:
|
||
|
||
a) cause the modified files to carry prominent notices stating
|
||
that you changed the files and the date of any change; and
|
||
|
||
b) cause the whole of any work that you distribute or publish,
|
||
that in whole or in part contains or is a derivative of this
|
||
program or any part thereof, to be licensed at no charge to all
|
||
third parties on terms identical to those contained in this
|
||
License Agreement (except that you may choose to grant more extensive
|
||
warranty protection to some or all third parties, at your option).
|
||
|
||
c) You may charge a distribution fee for the physical act of
|
||
transferring a copy, and you may at your option offer warranty
|
||
protection in exchange for a fee.
|
||
|
||
Mere aggregation of another unrelated program with this program (or its
|
||
derivative) on a volume of a storage or distribution medium does not bring
|
||
the other program under the scope of these terms.
|
||
|
||
3. You may copy and distribute this program or any portion of it in
|
||
compiled, executable or object code form under the terms of Paragraphs
|
||
1 and 2 above provided that you do the following:
|
||
|
||
a) accompany it with the complete corresponding machine-readable
|
||
source code, which must be distributed under the terms of
|
||
Paragraphs 1 and 2 above; or,
|
||
|
||
b) accompany it with a written offer, valid for at least three
|
||
years, to give any third party free (except for a nominal
|
||
shipping charge) a complete machine-readable copy of the
|
||
corresponding source code, to be distributed under the terms of
|
||
Paragraphs 1 and 2 above; or,
|
||
|
||
c) accompany it with the information you received as to where the
|
||
corresponding source code may be obtained. (This alternative is
|
||
allowed only for noncommercial distribution and only if you
|
||
received the program in object code or executable form alone.)
|
||
|
||
For an executable file, complete source code means all the source code for
|
||
all modules it contains; but, as a special exception, it need not include
|
||
source code for modules which are standard libraries that accompany the
|
||
operating system on which the executable file runs.
|
||
|
||
4. You may not copy, sublicense, distribute or transfer this program
|
||
except as expressly provided under this License Agreement. Any attempt
|
||
otherwise to copy, sublicense, distribute or transfer this program is void and
|
||
your rights to use the program under this License agreement shall be
|
||
automatically terminated. However, parties who have received computer
|
||
software programs from you with this License Agreement will not have
|
||
their licenses terminated so long as such parties remain in full compliance.
|
||
|
||
5. If you wish to incorporate parts of this program into other free
|
||
programs whose distribution conditions are different, write to the Free
|
||
Software Foundation at 675 Mass Ave, Cambridge, MA 02139. We have not yet
|
||
worked out a simple rule that can be stated here, but we will often permit
|
||
this. We will be guided by the two goals of preserving the free status of
|
||
all derivatives our free software and of promoting the sharing and reuse of
|
||
software.
|
||
|
||
|
||
In other words, you are welcome to use, share and improve this program.
|
||
You are forbidden to forbid anyone else to use, share and improve
|
||
what you give them. Help stamp out software-hoarding!
|
||
|
||
$Id: dfa.h,v 1.3 1993/11/13 02:26:36 jtc Exp $
|
||
*/
|
||
|
||
#ifdef __STDC__
|
||
|
||
#ifdef SOMEDAY
|
||
#define ISALNUM(c) isalnum(c)
|
||
#define ISALPHA(c) isalpha(c)
|
||
#define ISUPPER(c) isupper(c)
|
||
#else
|
||
#define ISALNUM(c) (isascii(c) && isalnum(c))
|
||
#define ISALPHA(c) (isascii(c) && isalpha(c))
|
||
#define ISUPPER(c) (isascii(c) && isupper(c))
|
||
#endif
|
||
|
||
#else /* ! __STDC__ */
|
||
|
||
#define const
|
||
|
||
#define ISALNUM(c) (isascii(c) && isalnum(c))
|
||
#define ISALPHA(c) (isascii(c) && isalpha(c))
|
||
#define ISUPPER(c) (isascii(c) && isupper(c))
|
||
|
||
#endif /* ! __STDC__ */
|
||
|
||
/* 1 means plain parentheses serve as grouping, and backslash
|
||
parentheses are needed for literal searching.
|
||
0 means backslash-parentheses are grouping, and plain parentheses
|
||
are for literal searching. */
|
||
#ifndef RE_NO_BK_PARENS
|
||
#define RE_NO_BK_PARENS 1L
|
||
#endif
|
||
|
||
/* 1 means plain | serves as the "or"-operator, and \| is a literal.
|
||
0 means \| serves as the "or"-operator, and | is a literal. */
|
||
#ifndef RE_NO_BK_VBAR
|
||
#define RE_NO_BK_VBAR (1L << 1)
|
||
#endif
|
||
|
||
/* 0 means plain + or ? serves as an operator, and \+, \? are literals.
|
||
1 means \+, \? are operators and plain +, ? are literals. */
|
||
#ifndef RE_BK_PLUS_QM
|
||
#define RE_BK_PLUS_QM (1L << 2)
|
||
#endif
|
||
|
||
/* 1 means | binds tighter than ^ or $.
|
||
0 means the contrary. */
|
||
#ifndef RE_TIGHT_VBAR
|
||
#define RE_TIGHT_VBAR (1L << 3)
|
||
#endif
|
||
|
||
/* 1 means treat \n as an _OR operator
|
||
0 means treat it as a normal character */
|
||
#ifndef RE_NEWLINE_OR
|
||
#define RE_NEWLINE_OR (1L << 4)
|
||
#endif
|
||
|
||
/* 0 means that a special characters (such as *, ^, and $) always have
|
||
their special meaning regardless of the surrounding context.
|
||
1 means that special characters may act as normal characters in some
|
||
contexts. Specifically, this applies to:
|
||
^ - only special at the beginning, or after ( or |
|
||
$ - only special at the end, or before ) or |
|
||
*, +, ? - only special when not after the beginning, (, or | */
|
||
#ifndef RE_CONTEXT_INDEP_OPS
|
||
#define RE_CONTEXT_INDEP_OPS (1L << 5)
|
||
#endif
|
||
|
||
/* 1 means that \ in a character class escapes the next character (typically
|
||
a hyphen. It also is overloaded to mean that hyphen at the end of the range
|
||
is allowable and means that the hyphen is to be taken literally. */
|
||
#define RE_AWK_CLASS_HACK (1L << 6)
|
||
|
||
/* Now define combinations of bits for the standard possibilities. */
|
||
#ifdef notdef
|
||
#define RE_SYNTAX_AWK (RE_NO_BK_PARENS | RE_NO_BK_VBAR | RE_CONTEXT_INDEP_OPS)
|
||
#define RE_SYNTAX_EGREP (RE_SYNTAX_AWK | RE_NEWLINE_OR)
|
||
#define RE_SYNTAX_GREP (RE_BK_PLUS_QM | RE_NEWLINE_OR)
|
||
#define RE_SYNTAX_EMACS 0
|
||
#endif
|
||
|
||
/* The NULL pointer. */
|
||
#ifndef NULL
|
||
#define NULL 0
|
||
#endif
|
||
|
||
/* Number of bits in an unsigned char. */
|
||
#ifndef CHARBITS
|
||
#define CHARBITS 8
|
||
#endif
|
||
|
||
/* First integer value that is greater than any character code. */
|
||
#define _NOTCHAR (1 << CHARBITS)
|
||
|
||
/* INTBITS need not be exact, just a lower bound. */
|
||
#ifndef INTBITS
|
||
#define INTBITS (CHARBITS * sizeof (int))
|
||
#endif
|
||
|
||
/* Number of ints required to hold a bit for every character. */
|
||
#define _CHARSET_INTS ((_NOTCHAR + INTBITS - 1) / INTBITS)
|
||
|
||
/* Sets of unsigned characters are stored as bit vectors in arrays of ints. */
|
||
typedef int _charset[_CHARSET_INTS];
|
||
|
||
/* The regexp is parsed into an array of tokens in postfix form. Some tokens
|
||
are operators and others are terminal symbols. Most (but not all) of these
|
||
codes are returned by the lexical analyzer. */
|
||
#ifdef __STDC__
|
||
|
||
typedef enum
|
||
{
|
||
_END = -1, /* _END is a terminal symbol that matches the
|
||
end of input; any value of _END or less in
|
||
the parse tree is such a symbol. Accepting
|
||
states of the DFA are those that would have
|
||
a transition on _END. */
|
||
|
||
/* Ordinary character values are terminal symbols that match themselves. */
|
||
|
||
_EMPTY = _NOTCHAR, /* _EMPTY is a terminal symbol that matches
|
||
the empty string. */
|
||
|
||
_BACKREF, /* _BACKREF is generated by \<digit>; it
|
||
it not completely handled. If the scanner
|
||
detects a transition on backref, it returns
|
||
a kind of "semi-success" indicating that
|
||
the match will have to be verified with
|
||
a backtracking matcher. */
|
||
|
||
_BEGLINE, /* _BEGLINE is a terminal symbol that matches
|
||
the empty string if it is at the beginning
|
||
of a line. */
|
||
|
||
_ALLBEGLINE, /* _ALLBEGLINE is a terminal symbol that
|
||
matches the empty string if it is at the
|
||
beginning of a line; _ALLBEGLINE applies
|
||
to the entire regexp and can only occur
|
||
as the first token thereof. _ALLBEGLINE
|
||
never appears in the parse tree; a _BEGLINE
|
||
is prepended with _CAT to the entire
|
||
regexp instead. */
|
||
|
||
_ENDLINE, /* _ENDLINE is a terminal symbol that matches
|
||
the empty string if it is at the end of
|
||
a line. */
|
||
|
||
_ALLENDLINE, /* _ALLENDLINE is to _ENDLINE as _ALLBEGLINE
|
||
is to _BEGLINE. */
|
||
|
||
_BEGWORD, /* _BEGWORD is a terminal symbol that matches
|
||
the empty string if it is at the beginning
|
||
of a word. */
|
||
|
||
_ENDWORD, /* _ENDWORD is a terminal symbol that matches
|
||
the empty string if it is at the end of
|
||
a word. */
|
||
|
||
_LIMWORD, /* _LIMWORD is a terminal symbol that matches
|
||
the empty string if it is at the beginning
|
||
or the end of a word. */
|
||
|
||
_NOTLIMWORD, /* _NOTLIMWORD is a terminal symbol that
|
||
matches the empty string if it is not at
|
||
the beginning or end of a word. */
|
||
|
||
_QMARK, /* _QMARK is an operator of one argument that
|
||
matches zero or one occurences of its
|
||
argument. */
|
||
|
||
_STAR, /* _STAR is an operator of one argument that
|
||
matches the Kleene closure (zero or more
|
||
occurrences) of its argument. */
|
||
|
||
_PLUS, /* _PLUS is an operator of one argument that
|
||
matches the positive closure (one or more
|
||
occurrences) of its argument. */
|
||
|
||
_CAT, /* _CAT is an operator of two arguments that
|
||
matches the concatenation of its
|
||
arguments. _CAT is never returned by the
|
||
lexical analyzer. */
|
||
|
||
_OR, /* _OR is an operator of two arguments that
|
||
matches either of its arguments. */
|
||
|
||
_LPAREN, /* _LPAREN never appears in the parse tree,
|
||
it is only a lexeme. */
|
||
|
||
_RPAREN, /* _RPAREN never appears in the parse tree. */
|
||
|
||
_SET /* _SET and (and any value greater) is a
|
||
terminal symbol that matches any of a
|
||
class of characters. */
|
||
} _token;
|
||
|
||
#else /* ! __STDC__ */
|
||
|
||
typedef short _token;
|
||
|
||
#define _END -1
|
||
#define _EMPTY _NOTCHAR
|
||
#define _BACKREF (_EMPTY + 1)
|
||
#define _BEGLINE (_EMPTY + 2)
|
||
#define _ALLBEGLINE (_EMPTY + 3)
|
||
#define _ENDLINE (_EMPTY + 4)
|
||
#define _ALLENDLINE (_EMPTY + 5)
|
||
#define _BEGWORD (_EMPTY + 6)
|
||
#define _ENDWORD (_EMPTY + 7)
|
||
#define _LIMWORD (_EMPTY + 8)
|
||
#define _NOTLIMWORD (_EMPTY + 9)
|
||
#define _QMARK (_EMPTY + 10)
|
||
#define _STAR (_EMPTY + 11)
|
||
#define _PLUS (_EMPTY + 12)
|
||
#define _CAT (_EMPTY + 13)
|
||
#define _OR (_EMPTY + 14)
|
||
#define _LPAREN (_EMPTY + 15)
|
||
#define _RPAREN (_EMPTY + 16)
|
||
#define _SET (_EMPTY + 17)
|
||
|
||
#endif /* ! __STDC__ */
|
||
|
||
/* Sets are stored in an array in the compiled regexp; the index of the
|
||
array corresponding to a given set token is given by _SET_INDEX(t). */
|
||
#define _SET_INDEX(t) ((t) - _SET)
|
||
|
||
/* Sometimes characters can only be matched depending on the surrounding
|
||
context. Such context decisions depend on what the previous character
|
||
was, and the value of the current (lookahead) character. Context
|
||
dependent constraints are encoded as 8 bit integers. Each bit that
|
||
is set indicates that the constraint succeeds in the corresponding
|
||
context.
|
||
|
||
bit 7 - previous and current are newlines
|
||
bit 6 - previous was newline, current isn't
|
||
bit 5 - previous wasn't newline, current is
|
||
bit 4 - neither previous nor current is a newline
|
||
bit 3 - previous and current are word-constituents
|
||
bit 2 - previous was word-constituent, current isn't
|
||
bit 1 - previous wasn't word-constituent, current is
|
||
bit 0 - neither previous nor current is word-constituent
|
||
|
||
Word-constituent characters are those that satisfy isalnum().
|
||
|
||
The macro _SUCCEEDS_IN_CONTEXT determines whether a a given constraint
|
||
succeeds in a particular context. Prevn is true if the previous character
|
||
was a newline, currn is true if the lookahead character is a newline.
|
||
Prevl and currl similarly depend upon whether the previous and current
|
||
characters are word-constituent letters. */
|
||
#define _MATCHES_NEWLINE_CONTEXT(constraint, prevn, currn) \
|
||
((constraint) & (1 << (((prevn) ? 2 : 0) + ((currn) ? 1 : 0) + 4)))
|
||
#define _MATCHES_LETTER_CONTEXT(constraint, prevl, currl) \
|
||
((constraint) & (1 << (((prevl) ? 2 : 0) + ((currl) ? 1 : 0))))
|
||
#define _SUCCEEDS_IN_CONTEXT(constraint, prevn, currn, prevl, currl) \
|
||
(_MATCHES_NEWLINE_CONTEXT(constraint, prevn, currn) \
|
||
&& _MATCHES_LETTER_CONTEXT(constraint, prevl, currl))
|
||
|
||
/* The following macros give information about what a constraint depends on. */
|
||
#define _PREV_NEWLINE_DEPENDENT(constraint) \
|
||
(((constraint) & 0xc0) >> 2 != ((constraint) & 0x30))
|
||
#define _PREV_LETTER_DEPENDENT(constraint) \
|
||
(((constraint) & 0x0c) >> 2 != ((constraint) & 0x03))
|
||
|
||
/* Tokens that match the empty string subject to some constraint actually
|
||
work by applying that constraint to determine what may follow them,
|
||
taking into account what has gone before. The following values are
|
||
the constraints corresponding to the special tokens previously defined. */
|
||
#define _NO_CONSTRAINT 0xff
|
||
#define _BEGLINE_CONSTRAINT 0xcf
|
||
#define _ENDLINE_CONSTRAINT 0xaf
|
||
#define _BEGWORD_CONSTRAINT 0xf2
|
||
#define _ENDWORD_CONSTRAINT 0xf4
|
||
#define _LIMWORD_CONSTRAINT 0xf6
|
||
#define _NOTLIMWORD_CONSTRAINT 0xf9
|
||
|
||
/* States of the recognizer correspond to sets of positions in the parse
|
||
tree, together with the constraints under which they may be matched.
|
||
So a position is encoded as an index into the parse tree together with
|
||
a constraint. */
|
||
typedef struct
|
||
{
|
||
unsigned index; /* Index into the parse array. */
|
||
unsigned constraint; /* Constraint for matching this position. */
|
||
} _position;
|
||
|
||
/* Sets of positions are stored as arrays. */
|
||
typedef struct
|
||
{
|
||
_position *elems; /* Elements of this position set. */
|
||
int nelem; /* Number of elements in this set. */
|
||
} _position_set;
|
||
|
||
/* A state of the regexp consists of a set of positions, some flags,
|
||
and the token value of the lowest-numbered position of the state that
|
||
contains an _END token. */
|
||
typedef struct
|
||
{
|
||
int hash; /* Hash of the positions of this state. */
|
||
_position_set elems; /* Positions this state could match. */
|
||
char newline; /* True if previous state matched newline. */
|
||
char letter; /* True if previous state matched a letter. */
|
||
char backref; /* True if this state matches a \<digit>. */
|
||
unsigned char constraint; /* Constraint for this state to accept. */
|
||
int first_end; /* Token value of the first _END in elems. */
|
||
} _dfa_state;
|
||
|
||
/* If an r.e. is at most MUST_MAX characters long, we look for a string which
|
||
must appear in it; whatever's found is dropped into the struct reg. */
|
||
|
||
#define MUST_MAX 50
|
||
|
||
/* A compiled regular expression. */
|
||
struct regexp
|
||
{
|
||
/* Stuff built by the scanner. */
|
||
_charset *charsets; /* Array of character sets for _SET tokens. */
|
||
int cindex; /* Index for adding new charsets. */
|
||
int calloc; /* Number of charsets currently allocated. */
|
||
|
||
/* Stuff built by the parser. */
|
||
_token *tokens; /* Postfix parse array. */
|
||
int tindex; /* Index for adding new tokens. */
|
||
int talloc; /* Number of tokens currently allocated. */
|
||
int depth; /* Depth required of an evaluation stack
|
||
used for depth-first traversal of the
|
||
parse tree. */
|
||
int nleaves; /* Number of leaves on the parse tree. */
|
||
int nregexps; /* Count of parallel regexps being built
|
||
with regparse(). */
|
||
|
||
/* Stuff owned by the state builder. */
|
||
_dfa_state *states; /* States of the regexp. */
|
||
int sindex; /* Index for adding new states. */
|
||
int salloc; /* Number of states currently allocated. */
|
||
|
||
/* Stuff built by the structure analyzer. */
|
||
_position_set *follows; /* Array of follow sets, indexed by position
|
||
index. The follow of a position is the set
|
||
of positions containing characters that
|
||
could conceivably follow a character
|
||
matching the given position in a string
|
||
matching the regexp. Allocated to the
|
||
maximum possible position index. */
|
||
int searchflag; /* True if we are supposed to build a searching
|
||
as opposed to an exact matcher. A searching
|
||
matcher finds the first and shortest string
|
||
matching a regexp anywhere in the buffer,
|
||
whereas an exact matcher finds the longest
|
||
string matching, but anchored to the
|
||
beginning of the buffer. */
|
||
|
||
/* Stuff owned by the executor. */
|
||
int tralloc; /* Number of transition tables that have
|
||
slots so far. */
|
||
int trcount; /* Number of transition tables that have
|
||
actually been built. */
|
||
int **trans; /* Transition tables for states that can
|
||
never accept. If the transitions for a
|
||
state have not yet been computed, or the
|
||
state could possibly accept, its entry in
|
||
this table is NULL. */
|
||
int **realtrans; /* Trans always points to realtrans + 1; this
|
||
is so trans[-1] can contain NULL. */
|
||
int **fails; /* Transition tables after failing to accept
|
||
on a state that potentially could do so. */
|
||
int *success; /* Table of acceptance conditions used in
|
||
regexecute and computed in build_state. */
|
||
int *newlines; /* Transitions on newlines. The entry for a
|
||
newline in any transition table is always
|
||
-1 so we can count lines without wasting
|
||
too many cycles. The transition for a
|
||
newline is stored separately and handled
|
||
as a special case. Newline is also used
|
||
as a sentinel at the end of the buffer. */
|
||
char must[MUST_MAX];
|
||
int mustn;
|
||
};
|
||
|
||
/* Some macros for user access to regexp internals. */
|
||
|
||
/* ACCEPTING returns true if s could possibly be an accepting state of r. */
|
||
#define ACCEPTING(s, r) ((r).states[s].constraint)
|
||
|
||
/* ACCEPTS_IN_CONTEXT returns true if the given state accepts in the
|
||
specified context. */
|
||
#define ACCEPTS_IN_CONTEXT(prevn, currn, prevl, currl, state, reg) \
|
||
_SUCCEEDS_IN_CONTEXT((reg).states[state].constraint, \
|
||
prevn, currn, prevl, currl)
|
||
|
||
/* FIRST_MATCHING_REGEXP returns the index number of the first of parallel
|
||
regexps that a given state could accept. Parallel regexps are numbered
|
||
starting at 1. */
|
||
#define FIRST_MATCHING_REGEXP(state, reg) (-(reg).states[state].first_end)
|
||
|
||
/* Entry points. */
|
||
|
||
#ifdef __STDC__
|
||
|
||
/* Regsyntax() takes two arguments; the first sets the syntax bits described
|
||
earlier in this file, and the second sets the case-folding flag. */
|
||
extern void regsyntax(long, int);
|
||
|
||
/* Compile the given string of the given length into the given struct regexp.
|
||
Final argument is a flag specifying whether to build a searching or an
|
||
exact matcher. */
|
||
extern void regcompile(const char *, size_t, struct regexp *, int);
|
||
|
||
/* Execute the given struct regexp on the buffer of characters. The
|
||
first char * points to the beginning, and the second points to the
|
||
first character after the end of the buffer, which must be a writable
|
||
place so a sentinel end-of-buffer marker can be stored there. The
|
||
second-to-last argument is a flag telling whether to allow newlines to
|
||
be part of a string matching the regexp. The next-to-last argument,
|
||
if non-NULL, points to a place to increment every time we see a
|
||
newline. The final argument, if non-NULL, points to a flag that will
|
||
be set if further examination by a backtracking matcher is needed in
|
||
order to verify backreferencing; otherwise the flag will be cleared.
|
||
Returns NULL if no match is found, or a pointer to the first
|
||
character after the first & shortest matching string in the buffer. */
|
||
extern char *regexecute(struct regexp *, char *, char *, int, int *, int *);
|
||
|
||
/* Free the storage held by the components of a struct regexp. */
|
||
extern void reg_free(struct regexp *);
|
||
|
||
/* Entry points for people who know what they're doing. */
|
||
|
||
/* Initialize the components of a struct regexp. */
|
||
extern void reginit(struct regexp *);
|
||
|
||
/* Incrementally parse a string of given length into a struct regexp. */
|
||
extern void regparse(const char *, size_t, struct regexp *);
|
||
|
||
/* Analyze a parsed regexp; second argument tells whether to build a searching
|
||
or an exact matcher. */
|
||
extern void reganalyze(struct regexp *, int);
|
||
|
||
/* Compute, for each possible character, the transitions out of a given
|
||
state, storing them in an array of integers. */
|
||
extern void regstate(int, struct regexp *, int []);
|
||
|
||
/* Error handling. */
|
||
|
||
/* Regerror() is called by the regexp routines whenever an error occurs. It
|
||
takes a single argument, a NUL-terminated string describing the error.
|
||
The default reg_error() prints the error message to stderr and exits.
|
||
The user can provide a different reg_free() if so desired. */
|
||
extern void reg_error(const char *);
|
||
|
||
#else /* ! __STDC__ */
|
||
extern void regsyntax(), regcompile(), reg_free(), reginit(), regparse();
|
||
extern void reganalyze(), regstate(), reg_error();
|
||
extern char *regexecute();
|
||
#endif
|