1 /* 2 * Copyright 2023 Bill Sommerfeld <sommerfeld@hamachi.org> 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. 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 35 /* 36 * First, the stuff that ends up in the outside-world include file 37 * typedef off_t regoff_t; 38 * typedef struct { 39 * int re_magic; 40 * size_t re_nsub; // number of parenthesized subexpressions 41 * const char *re_endp; // end pointer for REG_PEND 42 * struct re_guts *re_g; // none of your business :-) 43 * } regex_t; 44 * typedef struct { 45 * regoff_t rm_so; // start of match 46 * regoff_t rm_eo; // end of match 47 * } regmatch_t; 48 */ 49 /* 50 * internals of regex_t 51 */ 52 #define MAGIC1 ((('r'^0200)<<8) | 'e') 53 54 /* 55 * The internal representation is a *strip*, a sequence of 56 * operators ending with an endmarker. (Some terminology etc. is a 57 * historical relic of earlier versions which used multiple strips.) 58 * Certain oddities in the representation are there to permit running 59 * the machinery backwards; in particular, any deviation from sequential 60 * flow must be marked at both its source and its destination. Some 61 * fine points: 62 * 63 * - OPLUS_ and O_PLUS are *inside* the loop they create. 64 * - OQUEST_ and O_QUEST are *outside* the bypass they create. 65 * - OCH_ and O_CH are *outside* the multi-way branch they create, while 66 * OOR1 and OOR2 are respectively the end and the beginning of one of 67 * the branches. Note that there is an implicit OOR2 following OCH_ 68 * and an implicit OOR1 preceding O_CH. 69 * 70 * In state representations, an operator's bit is on to signify a state 71 * immediately *preceding* "execution" of that operator. 72 */ 73 typedef unsigned int sop; /* strip operator */ 74 typedef unsigned int sopno; 75 #define OPRMASK 0xf8000000U 76 #define OPDMASK 0x07ffffffU 77 #define OPSHIFT ((unsigned)27) 78 #define OP(n) ((n)&OPRMASK) 79 #define OPND(n) ((n)&OPDMASK) 80 #define SOP(op, opnd) ((op)|(opnd)) 81 /* operators meaning operand */ 82 /* (back, fwd are offsets) */ 83 #define OEND (1U<<OPSHIFT) /* endmarker - */ 84 #define OCHAR (2U<<OPSHIFT) /* character wide character */ 85 #define OBOL (3U<<OPSHIFT) /* left anchor - */ 86 #define OEOL (4U<<OPSHIFT) /* right anchor - */ 87 #define OANY (5U<<OPSHIFT) /* . - */ 88 #define OANYOF (6U<<OPSHIFT) /* [...] set number */ 89 #define OBACK_ (7U<<OPSHIFT) /* begin \d paren number */ 90 #define O_BACK (8U<<OPSHIFT) /* end \d paren number */ 91 #define OPLUS_ (9U<<OPSHIFT) /* + prefix fwd to suffix */ 92 #define O_PLUS (10U<<OPSHIFT) /* + suffix back to prefix */ 93 #define OQUEST_ (11U<<OPSHIFT) /* ? prefix fwd to suffix */ 94 #define O_QUEST (12U<<OPSHIFT) /* ? suffix back to prefix */ 95 #define OLPAREN (13U<<OPSHIFT) /* ( fwd to ) */ 96 #define ORPAREN (14U<<OPSHIFT) /* ) back to ( */ 97 #define OCH_ (15U<<OPSHIFT) /* begin choice fwd to OOR2 */ 98 #define OOR1 (16U<<OPSHIFT) /* | pt. 1 back to OOR1 or OCH_ */ 99 #define OOR2 (17U<<OPSHIFT) /* | pt. 2 fwd to OOR2 or O_CH */ 100 #define O_CH (18U<<OPSHIFT) /* end choice back to OOR1 */ 101 #define OBOW (19U<<OPSHIFT) /* begin word - */ 102 #define OEOW (20U<<OPSHIFT) /* end word - */ 103 104 /* 105 * Structures for [] character-set representation. 106 */ 107 typedef struct { 108 wint_t min; 109 wint_t max; 110 } crange; 111 typedef struct { 112 unsigned char bmp[NC_MAX / 8]; 113 wctype_t *types; 114 unsigned int ntypes; 115 wint_t *wides; 116 unsigned int nwides; 117 crange *ranges; 118 unsigned int nranges; 119 int invert; 120 int icase; 121 } cset; 122 123 static inline int 124 CHIN1(int nc, cset *cs, wint_t ch) 125 { 126 unsigned int i; 127 128 assert(ch >= 0); 129 if (ch < nc) 130 return (((cs->bmp[ch >> 3] & (1 << (ch & 7))) != 0) ^ 131 cs->invert); 132 for (i = 0; i < cs->nwides; i++) { 133 if (cs->icase) { 134 if (ch == towlower(cs->wides[i]) || 135 ch == towupper(cs->wides[i])) 136 return (!cs->invert); 137 } else if (ch == cs->wides[i]) 138 return (!cs->invert); 139 } 140 for (i = 0; i < cs->nranges; i++) 141 if (cs->ranges[i].min <= ch && ch <= cs->ranges[i].max) 142 return (!cs->invert); 143 for (i = 0; i < cs->ntypes; i++) 144 if (iswctype(ch, cs->types[i])) 145 return (!cs->invert); 146 return (cs->invert); 147 } 148 149 static inline int 150 CHIN(int nc, cset *cs, wint_t ch) 151 { 152 153 assert(ch >= 0); 154 if (ch < nc) 155 return (((cs->bmp[ch >> 3] & (1 << (ch & 7))) != 0) ^ 156 cs->invert); 157 else if (cs->icase) 158 return (CHIN1(nc, cs, ch) || CHIN1(nc, cs, towlower(ch)) || 159 CHIN1(nc, cs, towupper(ch))); 160 else 161 return (CHIN1(nc, cs, ch)); 162 } 163 164 /* 165 * main compiled-expression structure 166 */ 167 struct re_guts { 168 int magic; 169 #define MAGIC2 ((('R'^0200)<<8)|'E') 170 sop *strip; /* malloced area for strip */ 171 unsigned int ncsets; /* number of csets in use */ 172 cset *sets; /* -> cset [ncsets] */ 173 int cflags; /* copy of regcomp() cflags argument */ 174 sopno nstates; /* = number of sops */ 175 sopno firststate; /* the initial OEND (normally 0) */ 176 sopno laststate; /* the final OEND */ 177 int iflags; /* internal flags */ 178 #define USEBOL 01 /* used ^ */ 179 #define USEEOL 02 /* used $ */ 180 #define BAD 04 /* something wrong */ 181 int nbol; /* number of ^ used */ 182 int neol; /* number of $ used */ 183 char *must; /* match must contain this string */ 184 int moffset; /* latest point at which must may be located */ 185 int *charjump; /* Boyer-Moore char jump table */ 186 int *matchjump; /* Boyer-Moore match jump table */ 187 int mlen; /* length of must */ 188 size_t nsub; /* copy of re_nsub */ 189 int backrefs; /* does it use back references? */ 190 sopno nplus; /* how deep does it nest +s? */ 191 unsigned int mb_cur_max; 192 }; 193 194 /* misc utilities */ 195 #define OUT (CHAR_MIN - 1) /* a non-character value */ 196 #define IGN (CHAR_MIN - 2) 197 #define ISWORD(c) (iswalnum((uch)(c)) || (c) == '_') 198