regex2.h revision 62391
1/*-
2 * Copyright (c) 1992, 1993, 1994 Henry Spencer.
3 * Copyright (c) 1992, 1993, 1994
4 *	The Regents of the University of California.  All rights reserved.
5 *
6 * This code is derived from software contributed to Berkeley by
7 * Henry Spencer.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 3. All advertising materials mentioning features or use of this software
18 *    must display the following acknowledgement:
19 *	This product includes software developed by the University of
20 *	California, Berkeley and its contributors.
21 * 4. Neither the name of the University nor the names of its contributors
22 *    may be used to endorse or promote products derived from this software
23 *    without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 *
37 *	@(#)regex2.h	8.4 (Berkeley) 3/20/94
38 *
39 * $FreeBSD: head/lib/libc/regex/regex2.h 62391 2000-07-02 10:58:07Z dcs $
40 */
41
42/*
43 * First, the stuff that ends up in the outside-world include file
44 = typedef off_t regoff_t;
45 = typedef struct {
46 = 	int re_magic;
47 = 	size_t re_nsub;		// number of parenthesized subexpressions
48 = 	const char *re_endp;	// end pointer for REG_PEND
49 = 	struct re_guts *re_g;	// none of your business :-)
50 = } regex_t;
51 = typedef struct {
52 = 	regoff_t rm_so;		// start of match
53 = 	regoff_t rm_eo;		// end of match
54 = } regmatch_t;
55 */
56/*
57 * internals of regex_t
58 */
59#define	MAGIC1	((('r'^0200)<<8) | 'e')
60
61/*
62 * The internal representation is a *strip*, a sequence of
63 * operators ending with an endmarker.  (Some terminology etc. is a
64 * historical relic of earlier versions which used multiple strips.)
65 * Certain oddities in the representation are there to permit running
66 * the machinery backwards; in particular, any deviation from sequential
67 * flow must be marked at both its source and its destination.  Some
68 * fine points:
69 *
70 * - OPLUS_ and O_PLUS are *inside* the loop they create.
71 * - OQUEST_ and O_QUEST are *outside* the bypass they create.
72 * - OCH_ and O_CH are *outside* the multi-way branch they create, while
73 *   OOR1 and OOR2 are respectively the end and the beginning of one of
74 *   the branches.  Note that there is an implicit OOR2 following OCH_
75 *   and an implicit OOR1 preceding O_CH.
76 *
77 * In state representations, an operator's bit is on to signify a state
78 * immediately *preceding* "execution" of that operator.
79 */
80typedef unsigned long sop;	/* strip operator */
81typedef long sopno;
82#define	OPRMASK	0xf8000000L
83#define	OPDMASK	0x07ffffffL
84#define	OPSHIFT	((unsigned)27)
85#define	OP(n)	((n)&OPRMASK)
86#define	OPND(n)	((n)&OPDMASK)
87#define	SOP(op, opnd)	((op)|(opnd))
88/* operators			   meaning	operand			*/
89/*						(back, fwd are offsets)	*/
90#define	OEND	(1L<<OPSHIFT)	/* endmarker	-			*/
91#define	OCHAR	(2L<<OPSHIFT)	/* character	unsigned char		*/
92#define	OBOL	(3L<<OPSHIFT)	/* left anchor	-			*/
93#define	OEOL	(4L<<OPSHIFT)	/* right anchor	-			*/
94#define	OANY	(5L<<OPSHIFT)	/* .		-			*/
95#define	OANYOF	(6L<<OPSHIFT)	/* [...]	set number		*/
96#define	OBACK_	(7L<<OPSHIFT)	/* begin \d	paren number		*/
97#define	O_BACK	(8L<<OPSHIFT)	/* end \d	paren number		*/
98#define	OPLUS_	(9L<<OPSHIFT)	/* + prefix	fwd to suffix		*/
99#define	O_PLUS	(10L<<OPSHIFT)	/* + suffix	back to prefix		*/
100#define	OQUEST_	(11L<<OPSHIFT)	/* ? prefix	fwd to suffix		*/
101#define	O_QUEST	(12L<<OPSHIFT)	/* ? suffix	back to prefix		*/
102#define	OLPAREN	(13L<<OPSHIFT)	/* (		fwd to )		*/
103#define	ORPAREN	(14L<<OPSHIFT)	/* )		back to (		*/
104#define	OCH_	(15L<<OPSHIFT)	/* begin choice	fwd to OOR2		*/
105#define	OOR1	(16L<<OPSHIFT)	/* | pt. 1	back to OOR1 or OCH_	*/
106#define	OOR2	(17L<<OPSHIFT)	/* | pt. 2	fwd to OOR2 or O_CH	*/
107#define	O_CH	(18L<<OPSHIFT)	/* end choice	back to OOR1		*/
108#define	OBOW	(19L<<OPSHIFT)	/* begin word	-			*/
109#define	OEOW	(20L<<OPSHIFT)	/* end word	-			*/
110
111/*
112 * Structure for [] character-set representation.  Character sets are
113 * done as bit vectors, grouped 8 to a byte vector for compactness.
114 * The individual set therefore has both a pointer to the byte vector
115 * and a mask to pick out the relevant bit of each byte.  A hash code
116 * simplifies testing whether two sets could be identical.
117 *
118 * This will get trickier for multicharacter collating elements.  As
119 * preliminary hooks for dealing with such things, we also carry along
120 * a string of multi-character elements, and decide the size of the
121 * vectors at run time.
122 */
123typedef struct {
124	uch *ptr;		/* -> uch [csetsize] */
125	uch mask;		/* bit within array */
126	short hash;             /* hash code */
127	size_t smultis;
128	char *multis;		/* -> char[smulti]  ab\0cd\0ef\0\0 */
129} cset;
130/* note that CHadd and CHsub are unsafe, and CHIN doesn't yield 0/1 */
131#define CHadd(cs, c)    ((cs)->ptr[(uch)(c)] |= (cs)->mask, (cs)->hash += (uch)(c))
132#define CHsub(cs, c)    ((cs)->ptr[(uch)(c)] &= ~(cs)->mask, (cs)->hash -= (uch)(c))
133#define	CHIN(cs, c)	((cs)->ptr[(uch)(c)] & (cs)->mask)
134#define	MCadd(p, cs, cp)	mcadd(p, cs, cp)	/* regcomp() internal fns */
135#define	MCsub(p, cs, cp)	mcsub(p, cs, cp)
136#define	MCin(p, cs, cp)	mcin(p, cs, cp)
137
138/* stuff for character categories */
139typedef unsigned char cat_t;
140
141/*
142 * main compiled-expression structure
143 */
144struct re_guts {
145	int magic;
146#		define	MAGIC2	((('R'^0200)<<8)|'E')
147	sop *strip;		/* malloced area for strip */
148	int csetsize;		/* number of bits in a cset vector */
149	int ncsets;		/* number of csets in use */
150	cset *sets;		/* -> cset [ncsets] */
151	uch *setbits;		/* -> uch[csetsize][ncsets/CHAR_BIT] */
152	int cflags;		/* copy of regcomp() cflags argument */
153	sopno nstates;		/* = number of sops */
154	sopno firststate;	/* the initial OEND (normally 0) */
155	sopno laststate;	/* the final OEND */
156	int iflags;		/* internal flags */
157#		define	USEBOL	01	/* used ^ */
158#		define	USEEOL	02	/* used $ */
159#		define	BAD	04	/* something wrong */
160	int nbol;		/* number of ^ used */
161	int neol;		/* number of $ used */
162	int ncategories;	/* how many character categories */
163	cat_t *categories;	/* ->catspace[-CHAR_MIN] */
164	char *must;		/* match must contain this string */
165	int moffset;		/* latest point at which must may be located */
166	int *charjump;		/* Boyer-Moore char jump table */
167	int *matchjump;		/* Boyer-Moore match jump table */
168	int mlen;		/* length of must */
169	size_t nsub;		/* copy of re_nsub */
170	int backrefs;		/* does it use back references? */
171	sopno nplus;		/* how deep does it nest +s? */
172	/* catspace must be last */
173	cat_t catspace[1];	/* actually [NC] */
174};
175
176/* misc utilities */
177#define	OUT	(CHAR_MAX+1)	/* a non-character value */
178#define ISWORD(c)       (isalnum((uch)(c)) || (c) == '_')
179