xref: /netbsd/external/bsd/nvi/dist/regex/regex2.h (revision 08d478e3)
1 /*	$NetBSD: regex2.h,v 1.2 2013/11/22 15:52:06 christos Exp $ */
2 /*-
3  * Copyright (c) 1992, 1993, 1994 Henry Spencer.
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 of the University of Toronto.
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. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the University of
21  *	California, Berkeley and its contributors.
22  * 4. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  *
38  *	@(#)regex2.h	8.3 (Berkeley) 3/16/94
39  */
40 
41 /*
42  * First, the stuff that ends up in the outside-world include file
43  = typedef off_t regoff_t;
44  = typedef struct {
45  = 	int re_magic;
46  = 	size_t re_nsub;		// number of parenthesized subexpressions
47  = 	const char *re_endp;	// end pointer for REG_PEND
48  = 	struct re_guts *re_g;	// none of your business :-)
49  = } regex_t;
50  = typedef struct {
51  = 	regoff_t rm_so;		// start of match
52  = 	regoff_t rm_eo;		// end of match
53  = } regmatch_t;
54  */
55 /*
56  * internals of regex_t
57  */
58 #define	MAGIC1	((('r'^0200)<<8) | 'e')
59 
60 /*
61  * The internal representation is a *strip*, a sequence of
62  * operators ending with an endmarker.  (Some terminology etc. is a
63  * historical relic of earlier versions which used multiple strips.)
64  * Certain oddities in the representation are there to permit running
65  * the machinery backwards; in particular, any deviation from sequential
66  * flow must be marked at both its source and its destination.  Some
67  * fine points:
68  *
69  * - OPLUS_ and O_PLUS are *inside* the loop they create.
70  * - OQUEST_ and O_QUEST are *outside* the bypass they create.
71  * - OCH_ and O_CH are *outside* the multi-way branch they create, while
72  *   OOR1 and OOR2 are respectively the end and the beginning of one of
73  *   the branches.  Note that there is an implicit OOR2 following OCH_
74  *   and an implicit OOR1 preceding O_CH.
75  *
76  * In state representations, an operator's bit is on to signify a state
77  * immediately *preceding* "execution" of that operator.
78  */
79 typedef char sop;	/* strip operator */
80 typedef size_t sopno;
81 /* operators			   meaning	operand			*/
82 /*						(back, fwd are offsets)	*/
83 #define	OEND	(1)		/* endmarker	-			*/
84 #define	OCHAR	(2)		/* character	unsigned char		*/
85 #define	OBOL	(3)		/* left anchor	-			*/
86 #define	OEOL	(4)		/* right anchor	-			*/
87 #define	OANY	(5)		/* .		-			*/
88 #define	OANYOF	(6)		/* [...]	set number		*/
89 #define	OBACK_	(7)		/* begin \d	paren number		*/
90 #define	O_BACK	(8)		/* end \d	paren number		*/
91 #define	OPLUS_	(9)		/* + prefix	fwd to suffix		*/
92 #define	O_PLUS	(10)		/* + suffix	back to prefix		*/
93 #define	OQUEST_	(11)		/* ? prefix	fwd to suffix		*/
94 #define	O_QUEST	(12)		/* ? suffix	back to prefix		*/
95 #define	OLPAREN	(13)		/* (		fwd to )		*/
96 #define	ORPAREN	(14)		/* )		back to (		*/
97 #define	OCH_	(15)		/* begin choice	fwd to OOR2		*/
98 #define	OOR1	(16)		/* | pt. 1	back to OOR1 or OCH_	*/
99 #define	OOR2	(17)		/* | pt. 2	fwd to OOR2 or O_CH	*/
100 #define	O_CH	(18)		/* end choice	back to OOR1		*/
101 #define	OBOW	(19)		/* begin word	-			*/
102 #define	OEOW	(20)		/* end word	-			*/
103 
104 /*
105  * Structure for [] character-set representation.  Character sets are
106  * done as bit vectors, grouped 8 to a byte vector for compactness.
107  * The individual set therefore has both a pointer to the byte vector
108  * and a mask to pick out the relevant bit of each byte.  A hash code
109  * simplifies testing whether two sets could be identical.
110  *
111  * This will get trickier for multicharacter collating elements.  As
112  * preliminary hooks for dealing with such things, we also carry along
113  * a string of multi-character elements, and decide the size of the
114  * vectors at run time.
115  */
116 typedef struct {
117 	uch *ptr;		/* -> uch [csetsize] */
118 	uch mask;		/* bit within array */
119 	uch hash;		/* hash code */
120 	size_t smultis;
121 	char *multis;		/* -> char[smulti]  ab\0cd\0ef\0\0 */
122 } cset;
123 /* note that CHadd and CHsub are unsafe, and CHIN doesn't yield 0/1 */
124 #define	CHadd(cs, c)	((cs)->ptr[(uch)(c)] |= (cs)->mask, (cs)->hash += (c))
125 #define	CHsub(cs, c)	((cs)->ptr[(uch)(c)] &= ~(cs)->mask, (cs)->hash -= (c))
126 #define	CHIN(cs, c)	((cs)->ptr[(uch)(c)] & (cs)->mask)
127 #define	MCadd(p, cs, cp)	mcadd(p, cs, cp)	/* regcomp() internal fns */
128 #define	MCsub(p, cs, cp)	mcsub(p, cs, cp)
129 #define	MCin(p, cs, cp)	mcin(p, cs, cp)
130 
131 /* stuff for character categories */
132 typedef RCHAR_T cat_t;
133 
134 /*
135  * main compiled-expression structure
136  */
137 struct re_guts {
138 	int magic;
139 #		define	MAGIC2	((('R'^0200)<<8)|'E')
140 	sop *strip;		/* malloced area for strip */
141 	RCHAR_T *stripdata;	/* malloced area for stripdata */
142 	size_t csetsize;	/* number of bits in a cset vector */
143 	size_t ncsets;		/* number of csets in use */
144 	cset *sets;		/* -> cset [ncsets] */
145 	uch *setbits;		/* -> uch[csetsize][ncsets/CHAR_BIT] */
146 	int cflags;		/* copy of regcomp() cflags argument */
147 	sopno nstates;		/* = number of sops */
148 	sopno firststate;	/* the initial OEND (normally 0) */
149 	sopno laststate;	/* the final OEND */
150 	int iflags;		/* internal flags */
151 #		define	USEBOL	01	/* used ^ */
152 #		define	USEEOL	02	/* used $ */
153 #		define	BAD	04	/* something wrong */
154 	size_t nbol;		/* number of ^ used */
155 	size_t neol;		/* number of $ used */
156 #if 0
157 	size_t ncategories;	/* how many character categories */
158 	cat_t *categories;	/* ->catspace[-CHAR_MIN] */
159 #endif
160 	RCHAR_T *must;		/* match must contain this string */
161 	size_t mlen;		/* length of must */
162 	size_t nsub;		/* copy of re_nsub */
163 	int backrefs;		/* does it use back references? */
164 	sopno nplus;		/* how deep does it nest +s? */
165 	/* catspace must be last */
166 #if 0
167 	cat_t catspace[1];	/* actually [NC] */
168 #endif
169 };
170 
171 /* misc utilities */
172 #define OUT	REOF	/* a non-character value */
173 #define	ISWORD(c) ((c) == '_' || (ISGRAPH((UCHAR_T)c) && !ISPUNCT((UCHAR_T)c)))
174