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      1 /*	$NetBSD: regex2.h,v 1.13 2011/10/09 18:23:00 christos Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1992, 1993, 1994
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * This code is derived from software contributed to Berkeley by
      8  * Henry Spencer.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  * 3. Neither the name of the University nor the names of its contributors
     19  *    may be used to endorse or promote products derived from this software
     20  *    without specific prior written permission.
     21  *
     22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     32  * SUCH DAMAGE.
     33  *
     34  *	@(#)regex2.h	8.4 (Berkeley) 3/20/94
     35  */
     36 
     37 /*-
     38  * Copyright (c) 1992, 1993, 1994 Henry Spencer.
     39  *
     40  * This code is derived from software contributed to Berkeley by
     41  * Henry Spencer.
     42  *
     43  * Redistribution and use in source and binary forms, with or without
     44  * modification, are permitted provided that the following conditions
     45  * are met:
     46  * 1. Redistributions of source code must retain the above copyright
     47  *    notice, this list of conditions and the following disclaimer.
     48  * 2. Redistributions in binary form must reproduce the above copyright
     49  *    notice, this list of conditions and the following disclaimer in the
     50  *    documentation and/or other materials provided with the distribution.
     51  * 3. All advertising materials mentioning features or use of this software
     52  *    must display the following acknowledgement:
     53  *	This product includes software developed by the University of
     54  *	California, Berkeley and its contributors.
     55  * 4. Neither the name of the University nor the names of its contributors
     56  *    may be used to endorse or promote products derived from this software
     57  *    without specific prior written permission.
     58  *
     59  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     60  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     61  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     62  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     63  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     64  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     65  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     66  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     67  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     68  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     69  * SUCH DAMAGE.
     70  *
     71  *	@(#)regex2.h	8.4 (Berkeley) 3/20/94
     72  */
     73 
     74 /*
     75  * First, the stuff that ends up in the outside-world include file
     76  = typedef off_t regoff_t;
     77  = typedef struct {
     78  = 	int re_magic;
     79  = 	size_t re_nsub;		// number of parenthesized subexpressions
     80  = 	const char *re_endp;	// end pointer for REG_PEND
     81  = 	struct re_guts *re_g;	// none of your business :-)
     82  = } regex_t;
     83  = typedef struct {
     84  = 	regoff_t rm_so;		// start of match
     85  = 	regoff_t rm_eo;		// end of match
     86  = } regmatch_t;
     87  */
     88 /*
     89  * internals of regex_t
     90  */
     91 #define	MAGIC1	((('r'^0200)<<8) | 'e')
     92 
     93 /*
     94  * The internal representation is a *strip*, a sequence of
     95  * operators ending with an endmarker.  (Some terminology etc. is a
     96  * historical relic of earlier versions which used multiple strips.)
     97  * Certain oddities in the representation are there to permit running
     98  * the machinery backwards; in particular, any deviation from sequential
     99  * flow must be marked at both its source and its destination.  Some
    100  * fine points:
    101  *
    102  * - OPLUS_ and O_PLUS are *inside* the loop they create.
    103  * - OQUEST_ and O_QUEST are *outside* the bypass they create.
    104  * - OCH_ and O_CH are *outside* the multi-way branch they create, while
    105  *   OOR1 and OOR2 are respectively the end and the beginning of one of
    106  *   the branches.  Note that there is an implicit OOR2 following OCH_
    107  *   and an implicit OOR1 preceding O_CH.
    108  *
    109  * In state representations, an operator's bit is on to signify a state
    110  * immediately *preceding* "execution" of that operator.
    111  */
    112 typedef u_int32_t sop;	/* strip operator */
    113 typedef size_t sopno;
    114 #define	OPRMASK	((u_int32_t)0xf8000000UL)
    115 #define	OPDMASK	((u_int32_t)0x07ffffffUL)
    116 #define	OPSHIFT	((unsigned)27)
    117 #define	OP(n)	((n)&OPRMASK)
    118 #define	OPND(n)	((int)((n)&OPDMASK))
    119 #define	SOP(op, opnd)	((op)|(opnd))
    120 
    121 #define OPC(n)	(((u_int32_t)(n))<<OPSHIFT)
    122 /* operators		   meaning	operand			*/
    123 /*					(back, fwd are offsets)	*/
    124 #define	OEND	OPC(1)	/* endmarker	-			*/
    125 #define	OCHAR	OPC(2)	/* character	unsigned char		*/
    126 #define	OBOL	OPC(3)	/* left anchor	-			*/
    127 #define	OEOL	OPC(4)	/* right anchor	-			*/
    128 #define	OANY	OPC(5)	/* .		-			*/
    129 #define	OANYOF	OPC(6)	/* [...]	set number		*/
    130 #define	OBACK_	OPC(7)	/* begin \d	paren number		*/
    131 #define	O_BACK	OPC(8)	/* end \d	paren number		*/
    132 #define	OPLUS_	OPC(9)	/* + prefix	fwd to suffix		*/
    133 #define	O_PLUS	OPC(10)	/* + suffix	back to prefix		*/
    134 #define	OQUEST_	OPC(11)	/* ? prefix	fwd to suffix		*/
    135 #define	O_QUEST	OPC(12)	/* ? suffix	back to prefix		*/
    136 #define	OLPAREN	OPC(13)	/* (		fwd to )		*/
    137 #define	ORPAREN	OPC(14)	/* )		back to (		*/
    138 #define	OCH_	OPC(15)	/* begin choice	fwd to OOR2		*/
    139 #define	OOR1	OPC(16)	/* | pt. 1	back to OOR1 or OCH_	*/
    140 #define	OOR2	OPC(17)	/* | pt. 2	fwd to OOR2 or O_CH	*/
    141 #define	O_CH	OPC(18)	/* end choice	back to OOR1		*/
    142 #define	OBOW	OPC(19)	/* begin word	-			*/
    143 #define	OEOW	OPC(20)	/* end word	-			*/
    144 
    145 /*
    146  * Structure for [] character-set representation.  Character sets are
    147  * done as bit vectors, grouped 8 to a byte vector for compactness.
    148  * The individual set therefore has both a pointer to the byte vector
    149  * and a mask to pick out the relevant bit of each byte.  A hash code
    150  * simplifies testing whether two sets could be identical.
    151  *
    152  * This will get trickier for multicharacter collating elements.  As
    153  * preliminary hooks for dealing with such things, we also carry along
    154  * a string of multi-character elements, and decide the size of the
    155  * vectors at run time.
    156  */
    157 typedef struct {
    158 	uch *ptr;		/* -> uch [csetsize] */
    159 	uch mask;		/* bit within array */
    160 	uch hash;		/* hash code */
    161 	size_t smultis;
    162 	char *multis;		/* -> char[smulti]  ab\0cd\0ef\0\0 */
    163 } cset;
    164 /* note that CHadd and CHsub are unsafe, and CHIN doesn't yield 0/1 */
    165 #define	CHadd(cs, c)	((cs)->ptr[(uch)(c)] |= (cs)->mask, (cs)->hash += (c))
    166 #define	CHsub(cs, c)	((cs)->ptr[(uch)(c)] &= ~(cs)->mask, (cs)->hash -= (c))
    167 #define	CHIN(cs, c)	((cs)->ptr[(uch)(c)] & (cs)->mask)
    168 #define	MCadd(p, cs, cp)	mcadd(p, cs, cp)	/* regcomp() internal fns */
    169 #define	MCsub(p, cs, cp)	mcsub(p, cs, cp)
    170 #define	MCin(p, cs, cp)	mcin(p, cs, cp)
    171 
    172 /* stuff for character categories */
    173 typedef unsigned char cat_t;
    174 
    175 /*
    176  * main compiled-expression structure
    177  */
    178 struct re_guts {
    179 	int magic;
    180 #		define	MAGIC2	((('R'^0200)<<8)|'E')
    181 	sop *strip;		/* malloced area for strip */
    182 	size_t csetsize;	/* number of bits in a cset vector */
    183 	size_t ncsets;		/* number of csets in use */
    184 	cset *sets;		/* -> cset [ncsets] */
    185 	uch *setbits;		/* -> uch[csetsize][ncsets/CHAR_BIT] */
    186 	int cflags;		/* copy of regcomp() cflags argument */
    187 	sopno nstates;		/* = number of sops */
    188 	sopno firststate;	/* the initial OEND (normally 0) */
    189 	sopno laststate;	/* the final OEND */
    190 	int iflags;		/* internal flags */
    191 #		define	USEBOL	01	/* used ^ */
    192 #		define	USEEOL	02	/* used $ */
    193 #		define	BAD	04	/* something wrong */
    194 	size_t nbol;		/* number of ^ used */
    195 	size_t neol;		/* number of $ used */
    196 	size_t ncategories;	/* how many character categories */
    197 	cat_t *categories;	/* ->catspace[-CHAR_MIN] */
    198 	char *must;		/* match must contain this string */
    199 	size_t mlen;		/* length of must */
    200 	size_t nsub;		/* copy of re_nsub */
    201 	int backrefs;		/* does it use back references? */
    202 	sopno nplus;		/* how deep does it nest +s? */
    203 	/* catspace must be last */
    204 	cat_t catspace[1];	/* actually [NC] */
    205 };
    206 
    207 /* misc utilities */
    208 #define	OUT	(CHAR_MAX+1)	/* a non-character value */
    209 #define	ISWORD(c)	(isalnum((unsigned char)c) || (c) == '_')
    210