1 /* $OpenBSD: regex2.h,v 1.12 2021/01/03 17:07:58 tb Exp $ */ 2 3 /*- 4 * Copyright (c) 1992, 1993, 1994 Henry Spencer. 5 * Copyright (c) 1992, 1993, 1994 6 * The Regents of the University of California. All rights reserved. 7 * 8 * This code is derived from software contributed to Berkeley by 9 * Henry Spencer. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)regex2.h 8.4 (Berkeley) 3/20/94 36 */ 37 38 /* 39 * internals of regex_t 40 */ 41 #define MAGIC1 ((('r'^0200)<<8) | 'e') 42 43 /* 44 * The internal representation is a *strip*, a sequence of 45 * operators ending with an endmarker. (Some terminology etc. is a 46 * historical relic of earlier versions which used multiple strips.) 47 * Certain oddities in the representation are there to permit running 48 * the machinery backwards; in particular, any deviation from sequential 49 * flow must be marked at both its source and its destination. Some 50 * fine points: 51 * 52 * - OPLUS_ and O_PLUS are *inside* the loop they create. 53 * - OQUEST_ and O_QUEST are *outside* the bypass they create. 54 * - OCH_ and O_CH are *outside* the multi-way branch they create, while 55 * OOR1 and OOR2 are respectively the end and the beginning of one of 56 * the branches. Note that there is an implicit OOR2 following OCH_ 57 * and an implicit OOR1 preceding O_CH. 58 * 59 * In state representations, an operator's bit is on to signify a state 60 * immediately *preceding* "execution" of that operator. 61 */ 62 typedef unsigned long sop; /* strip operator */ 63 typedef long sopno; 64 #define OPRMASK 0xf8000000LU 65 #define OPDMASK 0x07ffffffLU 66 #define OPSHIFT ((unsigned)27) 67 #define OP(n) ((n)&OPRMASK) 68 #define OPND(n) ((n)&OPDMASK) 69 #define SOP(op, opnd) ((op)|(opnd)) 70 /* operators meaning operand */ 71 /* (back, fwd are offsets) */ 72 #define OEND (1LU<<OPSHIFT) /* endmarker - */ 73 #define OCHAR (2LU<<OPSHIFT) /* character unsigned char */ 74 #define OBOL (3LU<<OPSHIFT) /* left anchor - */ 75 #define OEOL (4LU<<OPSHIFT) /* right anchor - */ 76 #define OANY (5LU<<OPSHIFT) /* . - */ 77 #define OANYOF (6LU<<OPSHIFT) /* [...] set number */ 78 #define OBACK_ (7LU<<OPSHIFT) /* begin \d paren number */ 79 #define O_BACK (8LU<<OPSHIFT) /* end \d paren number */ 80 #define OPLUS_ (9LU<<OPSHIFT) /* + prefix fwd to suffix */ 81 #define O_PLUS (10LU<<OPSHIFT) /* + suffix back to prefix */ 82 #define OQUEST_ (11LU<<OPSHIFT) /* ? prefix fwd to suffix */ 83 #define O_QUEST (12LU<<OPSHIFT) /* ? suffix back to prefix */ 84 #define OLPAREN (13LU<<OPSHIFT) /* ( fwd to ) */ 85 #define ORPAREN (14LU<<OPSHIFT) /* ) back to ( */ 86 #define OCH_ (15LU<<OPSHIFT) /* begin choice fwd to OOR2 */ 87 #define OOR1 (16LU<<OPSHIFT) /* | pt. 1 back to OOR1 or OCH_ */ 88 #define OOR2 (17LU<<OPSHIFT) /* | pt. 2 fwd to OOR2 or O_CH */ 89 #define O_CH (18LU<<OPSHIFT) /* end choice back to OOR1 */ 90 #define OBOW (19LU<<OPSHIFT) /* begin word - */ 91 #define OEOW (20LU<<OPSHIFT) /* end word - */ 92 93 /* 94 * Structure for [] character-set representation. Character sets are 95 * done as bit vectors, grouped 8 to a byte vector for compactness. 96 * The individual set therefore has both a pointer to the byte vector 97 * and a mask to pick out the relevant bit of each byte. A hash code 98 * simplifies testing whether two sets could be identical. 99 * 100 * This will get trickier for multicharacter collating elements. As 101 * preliminary hooks for dealing with such things, we also carry along 102 * a string of multi-character elements, and decide the size of the 103 * vectors at run time. 104 */ 105 typedef struct { 106 uch *ptr; /* -> uch [csetsize] */ 107 uch mask; /* bit within array */ 108 uch hash; /* hash code */ 109 } cset; 110 111 static inline void 112 CHadd(cset *cs, char c) 113 { 114 cs->ptr[(uch)c] |= cs->mask; 115 cs->hash += c; 116 } 117 118 static inline void 119 CHsub(cset *cs, char c) 120 { 121 cs->ptr[(uch)c] &= ~cs->mask; 122 cs->hash -= c; 123 } 124 125 static inline int 126 CHIN(const cset *cs, char c) 127 { 128 return (cs->ptr[(uch)c] & cs->mask) != 0; 129 } 130 131 /* 132 * main compiled-expression structure 133 */ 134 struct re_guts { 135 int magic; 136 # define MAGIC2 ((('R'^0200)<<8)|'E') 137 sop *strip; /* malloced area for strip */ 138 int csetsize; /* number of bits in a cset vector */ 139 int ncsets; /* number of csets in use */ 140 cset *sets; /* -> cset [ncsets] */ 141 uch *setbits; /* -> uch[csetsize][ncsets/CHAR_BIT] */ 142 int cflags; /* copy of regcomp() cflags argument */ 143 sopno nstates; /* = number of sops */ 144 sopno firststate; /* the initial OEND (normally 0) */ 145 sopno laststate; /* the final OEND */ 146 int iflags; /* internal flags */ 147 # define USEBOL 01 /* used ^ */ 148 # define USEEOL 02 /* used $ */ 149 # define BAD 04 /* something wrong */ 150 int nbol; /* number of ^ used */ 151 int neol; /* number of $ used */ 152 char *must; /* match must contain this string */ 153 int mlen; /* length of must */ 154 size_t nsub; /* copy of re_nsub */ 155 int backrefs; /* does it use back references? */ 156 sopno nplus; /* how deep does it nest +s? */ 157 }; 158 159 /* misc utilities */ 160 #define OUT (CHAR_MAX+1) /* a non-character value */ 161 #define ISWORD(c) (isalnum(c) || (c) == '_') 162