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. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 /* 35 * First, the stuff that ends up in the outside-world include file 36 * typedef off_t regoff_t; 37 * typedef struct { 38 * int re_magic; 39 * size_t re_nsub; // number of parenthesized subexpressions 40 * const char *re_endp; // end pointer for REG_PEND 41 * struct re_guts *re_g; // none of your business :-) 42 * } regex_t; 43 * typedef struct { 44 * regoff_t rm_so; // start of match 45 * regoff_t rm_eo; // end of match 46 * } regmatch_t; 47 */ 48 /* 49 * internals of regex_t 50 */ 51 #define MAGIC1 ((('r'^0200)<<8) | 'e') 52 53 /* 54 * The internal representation is a *strip*, a sequence of 55 * operators ending with an endmarker. (Some terminology etc. is a 56 * historical relic of earlier versions which used multiple strips.) 57 * Certain oddities in the representation are there to permit running 58 * the machinery backwards; in particular, any deviation from sequential 59 * flow must be marked at both its source and its destination. Some 60 * fine points: 61 * 62 * - OPLUS_ and O_PLUS are *inside* the loop they create. 63 * - OQUEST_ and O_QUEST are *outside* the bypass they create. 64 * - OCH_ and O_CH are *outside* the multi-way branch they create, while 65 * OOR1 and OOR2 are respectively the end and the beginning of one of 66 * the branches. Note that there is an implicit OOR2 following OCH_ 67 * and an implicit OOR1 preceding O_CH. 68 * 69 * In state representations, an operator's bit is on to signify a state 70 * immediately *preceding* "execution" of that operator. 71 */ 72 typedef unsigned int sop; /* strip operator */ 73 typedef unsigned int sopno; 74 #define OPRMASK 0xf8000000U 75 #define OPDMASK 0x07ffffffU 76 #define OPSHIFT ((unsigned)27) 77 #define OP(n) ((n)&OPRMASK) 78 #define OPND(n) ((n)&OPDMASK) 79 #define SOP(op, opnd) ((op)|(opnd)) 80 /* operators meaning operand */ 81 /* (back, fwd are offsets) */ 82 #define OEND (1U<<OPSHIFT) /* endmarker - */ 83 #define OCHAR (2U<<OPSHIFT) /* character wide character */ 84 #define OBOL (3U<<OPSHIFT) /* left anchor - */ 85 #define OEOL (4U<<OPSHIFT) /* right anchor - */ 86 #define OANY (5U<<OPSHIFT) /* . - */ 87 #define OANYOF (6U<<OPSHIFT) /* [...] set number */ 88 #define OBACK_ (7U<<OPSHIFT) /* begin \d paren number */ 89 #define O_BACK (8U<<OPSHIFT) /* end \d paren number */ 90 #define OPLUS_ (9U<<OPSHIFT) /* + prefix fwd to suffix */ 91 #define O_PLUS (10U<<OPSHIFT) /* + suffix back to prefix */ 92 #define OQUEST_ (11U<<OPSHIFT) /* ? prefix fwd to suffix */ 93 #define O_QUEST (12U<<OPSHIFT) /* ? suffix back to prefix */ 94 #define OLPAREN (13U<<OPSHIFT) /* ( fwd to ) */ 95 #define ORPAREN (14U<<OPSHIFT) /* ) back to ( */ 96 #define OCH_ (15U<<OPSHIFT) /* begin choice fwd to OOR2 */ 97 #define OOR1 (16U<<OPSHIFT) /* | pt. 1 back to OOR1 or OCH_ */ 98 #define OOR2 (17U<<OPSHIFT) /* | pt. 2 fwd to OOR2 or O_CH */ 99 #define O_CH (18U<<OPSHIFT) /* end choice back to OOR1 */ 100 #define OBOW (19U<<OPSHIFT) /* begin word - */ 101 #define OEOW (20U<<OPSHIFT) /* end word - */ 102 103 /* 104 * Structures for [] character-set representation. 105 */ 106 typedef struct { 107 wint_t min; 108 wint_t max; 109 } crange; 110 typedef struct { 111 unsigned char bmp[NC_MAX / 8]; 112 wctype_t *types; 113 unsigned int ntypes; 114 wint_t *wides; 115 unsigned int nwides; 116 crange *ranges; 117 unsigned int nranges; 118 int invert; 119 int icase; 120 } cset; 121 122 static int 123 CHIN1(cset *cs, wint_t ch) 124 { 125 unsigned int i; 126 127 assert(ch >= 0); 128 if (ch < NC) 129 return (((cs->bmp[ch >> 3] & (1 << (ch & 7))) != 0) ^ 130 cs->invert); 131 for (i = 0; i < cs->nwides; i++) { 132 if (cs->icase) { 133 if (ch == towlower(cs->wides[i]) || 134 ch == towupper(cs->wides[i])) 135 return (!cs->invert); 136 } else if (ch == cs->wides[i]) 137 return (!cs->invert); 138 } 139 for (i = 0; i < cs->nranges; i++) 140 if (cs->ranges[i].min <= ch && ch <= cs->ranges[i].max) 141 return (!cs->invert); 142 for (i = 0; i < cs->ntypes; i++) 143 if (iswctype(ch, cs->types[i])) 144 return (!cs->invert); 145 return (cs->invert); 146 } 147 148 static int 149 CHIN(cset *cs, wint_t ch) 150 { 151 152 assert(ch >= 0); 153 if (ch < NC) 154 return (((cs->bmp[ch >> 3] & (1 << (ch & 7))) != 0) ^ 155 cs->invert); 156 else if (cs->icase) 157 return (CHIN1(cs, ch) || CHIN1(cs, towlower(ch)) || 158 CHIN1(cs, towupper(ch))); 159 else 160 return (CHIN1(cs, ch)); 161 } 162 163 /* 164 * main compiled-expression structure 165 */ 166 struct re_guts { 167 int magic; 168 #define MAGIC2 ((('R'^0200)<<8)|'E') 169 sop *strip; /* malloced area for strip */ 170 unsigned int ncsets; /* number of csets in use */ 171 cset *sets; /* -> cset [ncsets] */ 172 int cflags; /* copy of regcomp() cflags argument */ 173 sopno nstates; /* = number of sops */ 174 sopno firststate; /* the initial OEND (normally 0) */ 175 sopno laststate; /* the final OEND */ 176 int iflags; /* internal flags */ 177 #define USEBOL 01 /* used ^ */ 178 #define USEEOL 02 /* used $ */ 179 #define BAD 04 /* something wrong */ 180 int nbol; /* number of ^ used */ 181 int neol; /* number of $ used */ 182 char *must; /* match must contain this string */ 183 int moffset; /* latest point at which must may be located */ 184 int *charjump; /* Boyer-Moore char jump table */ 185 int *matchjump; /* Boyer-Moore match jump table */ 186 int mlen; /* length of must */ 187 size_t nsub; /* copy of re_nsub */ 188 int backrefs; /* does it use back references? */ 189 sopno nplus; /* how deep does it nest +s? */ 190 }; 191 192 /* misc utilities */ 193 #define OUT (CHAR_MIN - 1) /* a non-character value */ 194 #define IGN (CHAR_MIN - 2) 195 #define ISWORD(c) (iswalnum((uch)(c)) || (c) == '_') 196