denyhosts/clamscan/libclamav/regex/regex2.h
2022-10-22 18:41:00 +08:00

162 lines
6.2 KiB
C

/* $OpenBSD: regex2.h,v 1.12 2021/01/03 17:07:58 tb Exp $ */
/*-
* Copyright (c) 1992, 1993, 1994 Henry Spencer.
* Copyright (c) 1992, 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Henry Spencer.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)regex2.h 8.4 (Berkeley) 3/20/94
*/
/*
* internals of regex_t
*/
#define MAGIC1 ((('r'^0200)<<8) | 'e')
/*
* The internal representation is a *strip*, a sequence of
* operators ending with an endmarker. (Some terminology etc. is a
* historical relic of earlier versions which used multiple strips.)
* Certain oddities in the representation are there to permit running
* the machinery backwards; in particular, any deviation from sequential
* flow must be marked at both its source and its destination. Some
* fine points:
*
* - OPLUS_ and O_PLUS are *inside* the loop they create.
* - OQUEST_ and O_QUEST are *outside* the bypass they create.
* - OCH_ and O_CH are *outside* the multi-way branch they create, while
* OOR1 and OOR2 are respectively the end and the beginning of one of
* the branches. Note that there is an implicit OOR2 following OCH_
* and an implicit OOR1 preceding O_CH.
*
* In state representations, an operator's bit is on to signify a state
* immediately *preceding* "execution" of that operator.
*/
typedef unsigned long sop; /* strip operator */
typedef long sopno;
#define OPRMASK 0xf8000000LU
#define OPDMASK 0x07ffffffLU
#define OPSHIFT ((unsigned)27)
#define OP(n) ((n)&OPRMASK)
#define OPND(n) ((n)&OPDMASK)
#define SOP(op, opnd) ((op)|(opnd))
/* operators meaning operand */
/* (back, fwd are offsets) */
#define OEND (1LU<<OPSHIFT) /* endmarker - */
#define OCHAR (2LU<<OPSHIFT) /* character unsigned char */
#define OBOL (3LU<<OPSHIFT) /* left anchor - */
#define OEOL (4LU<<OPSHIFT) /* right anchor - */
#define OANY (5LU<<OPSHIFT) /* . - */
#define OANYOF (6LU<<OPSHIFT) /* [...] set number */
#define OBACK_ (7LU<<OPSHIFT) /* begin \d paren number */
#define O_BACK (8LU<<OPSHIFT) /* end \d paren number */
#define OPLUS_ (9LU<<OPSHIFT) /* + prefix fwd to suffix */
#define O_PLUS (10LU<<OPSHIFT) /* + suffix back to prefix */
#define OQUEST_ (11LU<<OPSHIFT) /* ? prefix fwd to suffix */
#define O_QUEST (12LU<<OPSHIFT) /* ? suffix back to prefix */
#define OLPAREN (13LU<<OPSHIFT) /* ( fwd to ) */
#define ORPAREN (14LU<<OPSHIFT) /* ) back to ( */
#define OCH_ (15LU<<OPSHIFT) /* begin choice fwd to OOR2 */
#define OOR1 (16LU<<OPSHIFT) /* | pt. 1 back to OOR1 or OCH_ */
#define OOR2 (17LU<<OPSHIFT) /* | pt. 2 fwd to OOR2 or O_CH */
#define O_CH (18LU<<OPSHIFT) /* end choice back to OOR1 */
#define OBOW (19LU<<OPSHIFT) /* begin word - */
#define OEOW (20LU<<OPSHIFT) /* end word - */
/*
* Structure for [] character-set representation. Character sets are
* done as bit vectors, grouped 8 to a byte vector for compactness.
* The individual set therefore has both a pointer to the byte vector
* and a mask to pick out the relevant bit of each byte. A hash code
* simplifies testing whether two sets could be identical.
*
* This will get trickier for multicharacter collating elements. As
* preliminary hooks for dealing with such things, we also carry along
* a string of multi-character elements, and decide the size of the
* vectors at run time.
*/
typedef struct {
uch *ptr; /* -> uch [csetsize] */
uch mask; /* bit within array */
uch hash; /* hash code */
} cset;
static inline void
CHadd(cset *cs, char c)
{
cs->ptr[(uch)c] |= cs->mask;
cs->hash += c;
}
static inline void
CHsub(cset *cs, char c)
{
cs->ptr[(uch)c] &= ~cs->mask;
cs->hash -= c;
}
static inline int
CHIN(const cset *cs, char c)
{
return (cs->ptr[(uch)c] & cs->mask) != 0;
}
/*
* main compiled-expression structure
*/
struct re_guts {
# define MAGIC2 ((('R'^0200)<<8)|'E')
sop *strip; /* malloced area for strip */
cset *sets; /* -> cset [ncsets] */
uch *setbits; /* -> uch[csetsize][ncsets/CHAR_BIT] */
int magic;
int csetsize; /* number of bits in a cset vector */
int ncsets; /* number of csets in use */
int cflags; /* copy of regcomp() cflags argument */
sopno nstates; /* = number of sops */
sopno firststate; /* the initial OEND (normally 0) */
sopno laststate; /* the final OEND */
int iflags; /* internal flags */
# define USEBOL 01 /* used ^ */
# define USEEOL 02 /* used $ */
# define REGEX_BAD 04 /* something wrong */
int nbol; /* number of ^ used */
int neol; /* number of $ used */
char *must; /* match must contain this string */
int mlen; /* length of must */
int backrefs; /* does it use back references? */
size_t nsub; /* copy of re_nsub */
sopno nplus; /* how deep does it nest +s? */
};
/* misc utilities */
#define OUT (CHAR_MAX+1) /* a non-character value */
#define ISWORD(c) (isalnum((c)&0xff) || (c) == '_')