regex2.h revision 1574
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 40/* 41 * First, the stuff that ends up in the outside-world include file 42 = typedef off_t regoff_t; 43 = typedef struct { 44 = int re_magic; 45 = size_t re_nsub; // number of parenthesized subexpressions 46 = const char *re_endp; // end pointer for REG_PEND 47 = struct re_guts *re_g; // none of your business :-) 48 = } regex_t; 49 = typedef struct { 50 = regoff_t rm_so; // start of match 51 = regoff_t rm_eo; // end of match 52 = } regmatch_t; 53 */ 54/* 55 * internals of regex_t 56 */ 57#define MAGIC1 ((('r'^0200)<<8) | 'e') 58 59/* 60 * The internal representation is a *strip*, a sequence of 61 * operators ending with an endmarker. (Some terminology etc. is a 62 * historical relic of earlier versions which used multiple strips.) 63 * Certain oddities in the representation are there to permit running 64 * the machinery backwards; in particular, any deviation from sequential 65 * flow must be marked at both its source and its destination. Some 66 * fine points: 67 * 68 * - OPLUS_ and O_PLUS are *inside* the loop they create. 69 * - OQUEST_ and O_QUEST are *outside* the bypass they create. 70 * - OCH_ and O_CH are *outside* the multi-way branch they create, while 71 * OOR1 and OOR2 are respectively the end and the beginning of one of 72 * the branches. Note that there is an implicit OOR2 following OCH_ 73 * and an implicit OOR1 preceding O_CH. 74 * 75 * In state representations, an operator's bit is on to signify a state 76 * immediately *preceding* "execution" of that operator. 77 */ 78typedef unsigned long sop; /* strip operator */ 79typedef long sopno; 80#define OPRMASK 0xf8000000 81#define OPDMASK 0x07ffffff 82#define OPSHIFT ((unsigned)27) 83#define OP(n) ((n)&OPRMASK) 84#define OPND(n) ((n)&OPDMASK) 85#define SOP(op, opnd) ((op)|(opnd)) 86/* operators meaning operand */ 87/* (back, fwd are offsets) */ 88#define OEND (1<<OPSHIFT) /* endmarker - */ 89#define OCHAR (2<<OPSHIFT) /* character unsigned char */ 90#define OBOL (3<<OPSHIFT) /* left anchor - */ 91#define OEOL (4<<OPSHIFT) /* right anchor - */ 92#define OANY (5<<OPSHIFT) /* . - */ 93#define OANYOF (6<<OPSHIFT) /* [...] set number */ 94#define OBACK_ (7<<OPSHIFT) /* begin \d paren number */ 95#define O_BACK (8<<OPSHIFT) /* end \d paren number */ 96#define OPLUS_ (9<<OPSHIFT) /* + prefix fwd to suffix */ 97#define O_PLUS (10<<OPSHIFT) /* + suffix back to prefix */ 98#define OQUEST_ (11<<OPSHIFT) /* ? prefix fwd to suffix */ 99#define O_QUEST (12<<OPSHIFT) /* ? suffix back to prefix */ 100#define OLPAREN (13<<OPSHIFT) /* ( fwd to ) */ 101#define ORPAREN (14<<OPSHIFT) /* ) back to ( */ 102#define OCH_ (15<<OPSHIFT) /* begin choice fwd to OOR2 */ 103#define OOR1 (16<<OPSHIFT) /* | pt. 1 back to OOR1 or OCH_ */ 104#define OOR2 (17<<OPSHIFT) /* | pt. 2 fwd to OOR2 or O_CH */ 105#define O_CH (18<<OPSHIFT) /* end choice back to OOR1 */ 106#define OBOW (19<<OPSHIFT) /* begin word - */ 107#define OEOW (20<<OPSHIFT) /* end word - */ 108 109/* 110 * Structure for [] character-set representation. Character sets are 111 * done as bit vectors, grouped 8 to a byte vector for compactness. 112 * The individual set therefore has both a pointer to the byte vector 113 * and a mask to pick out the relevant bit of each byte. A hash code 114 * simplifies testing whether two sets could be identical. 115 * 116 * This will get trickier for multicharacter collating elements. As 117 * preliminary hooks for dealing with such things, we also carry along 118 * a string of multi-character elements, and decide the size of the 119 * vectors at run time. 120 */ 121typedef struct { 122 uch *ptr; /* -> uch [csetsize] */ 123 uch mask; /* bit within array */ 124 uch hash; /* hash code */ 125 size_t smultis; 126 char *multis; /* -> char[smulti] ab\0cd\0ef\0\0 */ 127} cset; 128/* note that CHadd and CHsub are unsafe, and CHIN doesn't yield 0/1 */ 129#define CHadd(cs, c) ((cs)->ptr[(uch)(c)] |= (cs)->mask, (cs)->hash += (c)) 130#define CHsub(cs, c) ((cs)->ptr[(uch)(c)] &= ~(cs)->mask, (cs)->hash -= (c)) 131#define CHIN(cs, c) ((cs)->ptr[(uch)(c)] & (cs)->mask) 132#define MCadd(p, cs, cp) mcadd(p, cs, cp) /* regcomp() internal fns */ 133#define MCsub(p, cs, cp) mcsub(p, cs, cp) 134#define MCin(p, cs, cp) mcin(p, cs, cp) 135 136/* stuff for character categories */ 137typedef unsigned char cat_t; 138 139/* 140 * main compiled-expression structure 141 */ 142struct re_guts { 143 int magic; 144# define MAGIC2 ((('R'^0200)<<8)|'E') 145 sop *strip; /* malloced area for strip */ 146 int csetsize; /* number of bits in a cset vector */ 147 int ncsets; /* number of csets in use */ 148 cset *sets; /* -> cset [ncsets] */ 149 uch *setbits; /* -> uch[csetsize][ncsets/CHAR_BIT] */ 150 int cflags; /* copy of regcomp() cflags argument */ 151 sopno nstates; /* = number of sops */ 152 sopno firststate; /* the initial OEND (normally 0) */ 153 sopno laststate; /* the final OEND */ 154 int iflags; /* internal flags */ 155# define USEBOL 01 /* used ^ */ 156# define USEEOL 02 /* used $ */ 157# define BAD 04 /* something wrong */ 158 int nbol; /* number of ^ used */ 159 int neol; /* number of $ used */ 160 int ncategories; /* how many character categories */ 161 cat_t *categories; /* ->catspace[-CHAR_MIN] */ 162 char *must; /* match must contain this string */ 163 int mlen; /* length of must */ 164 size_t nsub; /* copy of re_nsub */ 165 int backrefs; /* does it use back references? */ 166 sopno nplus; /* how deep does it nest +s? */ 167 /* catspace must be last */ 168 cat_t catspace[1]; /* actually [NC] */ 169}; 170 171/* misc utilities */ 172#define OUT (CHAR_MAX+1) /* a non-character value */ 173#define ISWORD(c) (isalnum(c) || (c) == '_') 174