[444] | 1 | /*- |
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| 2 | * Copyright (c) 1992, 1993, 1994 Henry Spencer. |
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| 3 | * Copyright (c) 1992, 1993, 1994 |
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| 4 | * The Regents of the University of California. All rights reserved. |
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| 5 | * |
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| 6 | * This code is derived from software contributed to Berkeley by |
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| 7 | * Henry Spencer. |
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| 8 | * |
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| 9 | * Redistribution and use in source and binary forms, with or without |
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| 10 | * modification, are permitted provided that the following conditions |
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| 11 | * are met: |
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| 12 | * 1. Redistributions of source code must retain the above copyright |
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| 13 | * notice, this list of conditions and the following disclaimer. |
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| 14 | * 2. Redistributions in binary form must reproduce the above copyright |
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| 15 | * notice, this list of conditions and the following disclaimer in the |
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| 16 | * documentation and/or other materials provided with the distribution. |
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| 17 | * 4. Neither the name of the University nor the names of its contributors |
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| 18 | * may be used to endorse or promote products derived from this software |
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| 19 | * without specific prior written permission. |
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| 20 | * |
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| 21 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
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| 22 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
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| 23 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
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| 24 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
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| 25 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
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| 26 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
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| 27 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
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| 28 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
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| 29 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
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| 30 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
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| 31 | * SUCH DAMAGE. |
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| 32 | * |
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| 33 | * @(#)engine.c 8.5 (Berkeley) 3/20/94 |
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| 34 | */ |
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| 35 | |
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| 36 | #include <sys/cdefs.h> |
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| 37 | #include <_ansi.h> |
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| 38 | |
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| 39 | /* |
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| 40 | * The matching engine and friends. This file is #included by regexec.c |
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| 41 | * after suitable #defines of a variety of macros used herein, so that |
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| 42 | * different state representations can be used without duplicating masses |
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| 43 | * of code. |
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| 44 | */ |
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| 45 | |
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| 46 | #ifdef SNAMES |
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| 47 | #define matcher smatcher |
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| 48 | #define fast sfast |
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| 49 | #define slow sslow |
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| 50 | #define dissect sdissect |
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| 51 | #define backref sbackref |
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| 52 | #define step sstep |
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| 53 | #define print sprint |
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| 54 | #define at sat |
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| 55 | #define match smat |
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| 56 | #endif |
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| 57 | #ifdef LNAMES |
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| 58 | #define matcher lmatcher |
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| 59 | #define fast lfast |
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| 60 | #define slow lslow |
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| 61 | #define dissect ldissect |
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| 62 | #define backref lbackref |
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| 63 | #define step lstep |
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| 64 | #define print lprint |
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| 65 | #define at lat |
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| 66 | #define match lmat |
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| 67 | #endif |
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| 68 | |
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| 69 | /* another structure passed up and down to avoid zillions of parameters */ |
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| 70 | struct match { |
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| 71 | struct re_guts *g; |
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| 72 | int eflags; |
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| 73 | regmatch_t *pmatch; /* [nsub+1] (0 element unused) */ |
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| 74 | char *offp; /* offsets work from here */ |
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| 75 | char *beginp; /* start of string -- virtual NUL precedes */ |
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| 76 | char *endp; /* end of string -- virtual NUL here */ |
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| 77 | char *coldp; /* can be no match starting before here */ |
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| 78 | char **lastpos; /* [nplus+1] */ |
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| 79 | STATEVARS; |
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| 80 | states st; /* current states */ |
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| 81 | states fresh; /* states for a fresh start */ |
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| 82 | states tmp; /* temporary */ |
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| 83 | states empty; /* empty set of states */ |
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| 84 | }; |
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| 85 | |
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| 86 | /* ========= begin header generated by ./mkh ========= */ |
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| 87 | #ifdef __cplusplus |
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| 88 | extern "C" { |
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| 89 | #endif |
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| 90 | |
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| 91 | /* === engine.c === */ |
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| 92 | static int matcher(struct re_guts *g, char *string, size_t nmatch, regmatch_t pmatch[], int eflags); |
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| 93 | static char *dissect(struct match *m, char *start, char *stop, sopno startst, sopno stopst); |
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| 94 | static char *backref(struct match *m, char *start, char *stop, sopno startst, sopno stopst, sopno lev); |
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| 95 | static char *fast(struct match *m, char *start, char *stop, sopno startst, sopno stopst); |
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| 96 | static char *slow(struct match *m, char *start, char *stop, sopno startst, sopno stopst); |
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| 97 | static states step(struct re_guts *g, sopno start, sopno stop, states bef, int ch, states aft); |
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| 98 | #define BOL (OUT+1) |
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| 99 | #define EOL (BOL+1) |
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| 100 | #define BOLEOL (BOL+2) |
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| 101 | #define NOTHING (BOL+3) |
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| 102 | #define BOW (BOL+4) |
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| 103 | #define EOW (BOL+5) |
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| 104 | #define CODEMAX (BOL+5) /* highest code used */ |
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| 105 | #define NONCHAR(c) ((c) > CHAR_MAX) |
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| 106 | #define NNONCHAR (CODEMAX-CHAR_MAX) |
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| 107 | #ifdef REDEBUG |
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| 108 | static void print(struct match *m, char *caption, states st, int ch, FILE *d); |
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| 109 | #endif |
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| 110 | #ifdef REDEBUG |
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| 111 | static void at(struct match *m, char *title, char *start, char *stop, sopno startst, sopno stopst); |
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| 112 | #endif |
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| 113 | #ifdef REDEBUG |
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| 114 | static char *pchar(int ch); |
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| 115 | #endif |
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| 116 | |
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| 117 | #ifdef __cplusplus |
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| 118 | } |
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| 119 | #endif |
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| 120 | /* ========= end header generated by ./mkh ========= */ |
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| 121 | |
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| 122 | #ifdef REDEBUG |
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| 123 | #define SP(t, s, c) print(m, t, s, c, stdout) |
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| 124 | #define AT(t, p1, p2, s1, s2) at(m, t, p1, p2, s1, s2) |
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| 125 | #define NOTE(str) { if (m->eflags®_TRACE) printf("=%s\n", (str)); } |
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| 126 | #else |
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| 127 | #define SP(t, s, c) /* nothing */ |
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| 128 | #define AT(t, p1, p2, s1, s2) /* nothing */ |
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| 129 | #define NOTE(s) /* nothing */ |
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| 130 | #endif |
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| 131 | |
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| 132 | /* |
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| 133 | - matcher - the actual matching engine |
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| 134 | == static int matcher(struct re_guts *g, char *string, \ |
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| 135 | == size_t nmatch, regmatch_t pmatch[], int eflags); |
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| 136 | */ |
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| 137 | static int /* 0 success, REG_NOMATCH failure */ |
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| 138 | matcher(g, string, nmatch, pmatch, eflags) |
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| 139 | struct re_guts *g; |
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| 140 | char *string; |
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| 141 | size_t nmatch; |
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| 142 | regmatch_t pmatch[]; |
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| 143 | int eflags; |
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| 144 | { |
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| 145 | char *endp; |
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| 146 | int i; |
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| 147 | struct match mv; |
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| 148 | struct match *m = &mv; |
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| 149 | char *dp = NULL; |
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| 150 | const sopno gf = g->firststate+1; /* +1 for OEND */ |
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| 151 | const sopno gl = g->laststate; |
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| 152 | char *start; |
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| 153 | char *stop; |
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| 154 | /* Boyer-Moore algorithms variables */ |
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| 155 | char *pp; |
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| 156 | int cj, mj; |
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| 157 | char *mustfirst; |
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| 158 | char *mustlast; |
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| 159 | int *matchjump; |
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| 160 | int *charjump; |
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| 161 | |
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| 162 | /* simplify the situation where possible */ |
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| 163 | if (g->cflags®_NOSUB) |
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| 164 | nmatch = 0; |
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| 165 | if (eflags®_STARTEND) { |
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| 166 | start = string + pmatch[0].rm_so; |
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| 167 | stop = string + pmatch[0].rm_eo; |
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| 168 | } else { |
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| 169 | start = string; |
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| 170 | stop = start + strlen(start); |
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| 171 | } |
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| 172 | if (stop < start) |
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| 173 | return(REG_INVARG); |
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| 174 | |
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| 175 | /* prescreening; this does wonders for this rather slow code */ |
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| 176 | if (g->must != NULL) { |
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| 177 | if (g->charjump != NULL && g->matchjump != NULL) { |
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| 178 | mustfirst = g->must; |
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| 179 | mustlast = g->must + g->mlen - 1; |
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| 180 | charjump = g->charjump; |
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| 181 | matchjump = g->matchjump; |
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| 182 | pp = mustlast; |
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| 183 | for (dp = start+g->mlen-1; dp < stop;) { |
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| 184 | /* Fast skip non-matches */ |
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| 185 | while (dp < stop && charjump[(unsigned char) *dp]) |
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| 186 | dp += charjump[(unsigned char) *dp]; |
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| 187 | |
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| 188 | if (dp >= stop) |
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| 189 | break; |
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| 190 | |
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| 191 | /* Greedy matcher */ |
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| 192 | /* We depend on not being used for |
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| 193 | * for strings of length 1 |
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| 194 | */ |
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| 195 | while (*--dp == *--pp && pp != mustfirst); |
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| 196 | |
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| 197 | if (*dp == *pp) |
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| 198 | break; |
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| 199 | |
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| 200 | /* Jump to next possible match */ |
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| 201 | mj = matchjump[pp - mustfirst]; |
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| 202 | cj = charjump[(unsigned char) *dp]; |
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| 203 | dp += (cj < mj ? mj : cj); |
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| 204 | pp = mustlast; |
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| 205 | } |
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| 206 | if (pp != mustfirst) |
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| 207 | return(REG_NOMATCH); |
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| 208 | } else { |
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| 209 | for (dp = start; dp < stop; dp++) |
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| 210 | if (*dp == g->must[0] && |
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| 211 | stop - dp >= g->mlen && |
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| 212 | memcmp(dp, g->must, (size_t)g->mlen) == 0) |
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| 213 | break; |
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| 214 | if (dp == stop) /* we didn't find g->must */ |
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| 215 | return(REG_NOMATCH); |
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| 216 | } |
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| 217 | } |
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| 218 | |
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| 219 | /* match struct setup */ |
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| 220 | m->g = g; |
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| 221 | m->eflags = eflags; |
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| 222 | m->pmatch = NULL; |
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| 223 | m->lastpos = NULL; |
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| 224 | m->offp = string; |
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| 225 | m->beginp = start; |
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| 226 | m->endp = stop; |
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| 227 | STATESETUP(m, 4); |
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| 228 | SETUP(m->st); |
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| 229 | SETUP(m->fresh); |
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| 230 | SETUP(m->tmp); |
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| 231 | SETUP(m->empty); |
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| 232 | CLEAR(m->empty); |
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| 233 | |
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| 234 | /* Adjust start according to moffset, to speed things up */ |
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| 235 | if (g->moffset > -1) |
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| 236 | start = ((dp - g->moffset) < start) ? start : dp - g->moffset; |
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| 237 | |
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| 238 | /* this loop does only one repetition except for backrefs */ |
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| 239 | for (;;) { |
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| 240 | endp = fast(m, start, stop, gf, gl); |
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| 241 | if (endp == NULL) { /* a miss */ |
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| 242 | STATETEARDOWN(m); |
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| 243 | return(REG_NOMATCH); |
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| 244 | } |
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| 245 | if (nmatch == 0 && !g->backrefs) |
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| 246 | break; /* no further info needed */ |
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| 247 | |
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| 248 | /* where? */ |
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| 249 | assert(m->coldp != NULL); |
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| 250 | for (;;) { |
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| 251 | NOTE("finding start"); |
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| 252 | endp = slow(m, m->coldp, stop, gf, gl); |
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| 253 | if (endp != NULL) |
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| 254 | break; |
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| 255 | assert(m->coldp < m->endp); |
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| 256 | m->coldp++; |
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| 257 | } |
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| 258 | if (nmatch == 1 && !g->backrefs) |
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| 259 | break; /* no further info needed */ |
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| 260 | |
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| 261 | /* oh my, he wants the subexpressions... */ |
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| 262 | if (m->pmatch == NULL) |
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| 263 | m->pmatch = (regmatch_t *)malloc((m->g->nsub + 1) * |
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| 264 | sizeof(regmatch_t)); |
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| 265 | if (m->pmatch == NULL) { |
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| 266 | STATETEARDOWN(m); |
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| 267 | return(REG_ESPACE); |
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| 268 | } |
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| 269 | for (i = 1; i <= m->g->nsub; i++) |
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| 270 | m->pmatch[i].rm_so = m->pmatch[i].rm_eo = -1; |
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| 271 | if (!g->backrefs && !(m->eflags®_BACKR)) { |
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| 272 | NOTE("dissecting"); |
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| 273 | dp = dissect(m, m->coldp, endp, gf, gl); |
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| 274 | } else { |
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| 275 | if (g->nplus > 0 && m->lastpos == NULL) |
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| 276 | m->lastpos = (char **)malloc((g->nplus+1) * |
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| 277 | sizeof(char *)); |
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| 278 | if (g->nplus > 0 && m->lastpos == NULL) { |
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| 279 | free(m->pmatch); |
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| 280 | STATETEARDOWN(m); |
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| 281 | return(REG_ESPACE); |
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| 282 | } |
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| 283 | NOTE("backref dissect"); |
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| 284 | dp = backref(m, m->coldp, endp, gf, gl, (sopno)0); |
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| 285 | } |
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| 286 | if (dp != NULL) |
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| 287 | break; |
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| 288 | |
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| 289 | /* uh-oh... we couldn't find a subexpression-level match */ |
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| 290 | assert(g->backrefs); /* must be back references doing it */ |
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| 291 | assert(g->nplus == 0 || m->lastpos != NULL); |
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| 292 | for (;;) { |
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| 293 | if (dp != NULL || endp <= m->coldp) |
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| 294 | break; /* defeat */ |
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| 295 | NOTE("backoff"); |
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| 296 | endp = slow(m, m->coldp, endp-1, gf, gl); |
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| 297 | if (endp == NULL) |
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| 298 | break; /* defeat */ |
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| 299 | /* try it on a shorter possibility */ |
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| 300 | #ifndef NDEBUG |
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| 301 | for (i = 1; i <= m->g->nsub; i++) { |
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| 302 | assert(m->pmatch[i].rm_so == -1); |
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| 303 | assert(m->pmatch[i].rm_eo == -1); |
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| 304 | } |
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| 305 | #endif |
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| 306 | NOTE("backoff dissect"); |
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| 307 | dp = backref(m, m->coldp, endp, gf, gl, (sopno)0); |
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| 308 | } |
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| 309 | assert(dp == NULL || dp == endp); |
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| 310 | if (dp != NULL) /* found a shorter one */ |
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| 311 | break; |
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| 312 | |
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| 313 | /* despite initial appearances, there is no match here */ |
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| 314 | NOTE("false alarm"); |
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| 315 | start = m->coldp + 1; /* recycle starting later */ |
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| 316 | assert(start <= stop); |
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| 317 | } |
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| 318 | |
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| 319 | /* fill in the details if requested */ |
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| 320 | if (nmatch > 0) { |
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| 321 | pmatch[0].rm_so = m->coldp - m->offp; |
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| 322 | pmatch[0].rm_eo = endp - m->offp; |
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| 323 | } |
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| 324 | if (nmatch > 1) { |
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| 325 | assert(m->pmatch != NULL); |
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| 326 | for (i = 1; i < nmatch; i++) |
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| 327 | if (i <= m->g->nsub) |
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| 328 | pmatch[i] = m->pmatch[i]; |
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| 329 | else { |
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| 330 | pmatch[i].rm_so = -1; |
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| 331 | pmatch[i].rm_eo = -1; |
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| 332 | } |
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| 333 | } |
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| 334 | |
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| 335 | if (m->pmatch != NULL) |
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| 336 | free((char *)m->pmatch); |
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| 337 | if (m->lastpos != NULL) |
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| 338 | free((char *)m->lastpos); |
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| 339 | STATETEARDOWN(m); |
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| 340 | return(0); |
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| 341 | } |
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| 342 | |
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| 343 | /* |
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| 344 | - dissect - figure out what matched what, no back references |
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| 345 | == static char *dissect(struct match *m, char *start, \ |
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| 346 | == char *stop, sopno startst, sopno stopst); |
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| 347 | */ |
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| 348 | static char * /* == stop (success) always */ |
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| 349 | dissect(m, start, stop, startst, stopst) |
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| 350 | struct match *m; |
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| 351 | char *start; |
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| 352 | char *stop; |
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| 353 | sopno startst; |
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| 354 | sopno stopst; |
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| 355 | { |
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| 356 | int i; |
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| 357 | sopno ss; /* start sop of current subRE */ |
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| 358 | sopno es; /* end sop of current subRE */ |
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| 359 | char *sp; /* start of string matched by it */ |
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| 360 | char *stp; /* string matched by it cannot pass here */ |
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| 361 | char *rest; /* start of rest of string */ |
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| 362 | char *tail; /* string unmatched by rest of RE */ |
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| 363 | sopno ssub; /* start sop of subsubRE */ |
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| 364 | sopno esub; /* end sop of subsubRE */ |
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| 365 | char *ssp; /* start of string matched by subsubRE */ |
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| 366 | char *sep; /* end of string matched by subsubRE */ |
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| 367 | char *oldssp; /* previous ssp */ |
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| 368 | #if __GNUC_PREREQ (4, 6) |
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| 369 | /* dp is only used for assertion testing which, for some reason, is not |
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| 370 | recognized as usage. */ |
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| 371 | #pragma GCC diagnostic ignored "-Wunused-but-set-variable" |
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| 372 | #endif |
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| 373 | char *dp; |
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| 374 | |
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| 375 | AT("diss", start, stop, startst, stopst); |
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| 376 | sp = start; |
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| 377 | for (ss = startst; ss < stopst; ss = es) { |
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| 378 | /* identify end of subRE */ |
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| 379 | es = ss; |
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| 380 | switch (OP(m->g->strip[es])) { |
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| 381 | case OPLUS_: |
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| 382 | case OQUEST_: |
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| 383 | es += OPND(m->g->strip[es]); |
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| 384 | break; |
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| 385 | case OCH_: |
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| 386 | while (OP(m->g->strip[es]) != O_CH) |
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| 387 | es += OPND(m->g->strip[es]); |
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| 388 | break; |
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| 389 | } |
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| 390 | es++; |
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| 391 | |
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| 392 | /* figure out what it matched */ |
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| 393 | switch (OP(m->g->strip[ss])) { |
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| 394 | case OEND: |
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| 395 | assert(nope); |
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| 396 | break; |
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| 397 | case OCHAR: |
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| 398 | sp++; |
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| 399 | break; |
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| 400 | case OBOL: |
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| 401 | case OEOL: |
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| 402 | case OBOW: |
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| 403 | case OEOW: |
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| 404 | break; |
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| 405 | case OANY: |
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| 406 | case OANYOF: |
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| 407 | sp++; |
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| 408 | break; |
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| 409 | case OBACK_: |
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| 410 | case O_BACK: |
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| 411 | assert(nope); |
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| 412 | break; |
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| 413 | /* cases where length of match is hard to find */ |
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| 414 | case OQUEST_: |
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| 415 | stp = stop; |
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| 416 | for (;;) { |
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| 417 | /* how long could this one be? */ |
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| 418 | rest = slow(m, sp, stp, ss, es); |
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| 419 | assert(rest != NULL); /* it did match */ |
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| 420 | /* could the rest match the rest? */ |
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| 421 | tail = slow(m, rest, stop, es, stopst); |
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| 422 | if (tail == stop) |
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| 423 | break; /* yes! */ |
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| 424 | /* no -- try a shorter match for this one */ |
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| 425 | stp = rest - 1; |
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| 426 | assert(stp >= sp); /* it did work */ |
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| 427 | } |
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| 428 | ssub = ss + 1; |
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| 429 | esub = es - 1; |
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| 430 | /* did innards match? */ |
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| 431 | if (slow(m, sp, rest, ssub, esub) != NULL) { |
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| 432 | dp = dissect(m, sp, rest, ssub, esub); |
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| 433 | assert(dp == rest); |
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| 434 | } else /* no */ |
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| 435 | assert(sp == rest); |
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| 436 | sp = rest; |
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| 437 | break; |
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| 438 | case OPLUS_: |
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| 439 | stp = stop; |
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| 440 | for (;;) { |
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| 441 | /* how long could this one be? */ |
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| 442 | rest = slow(m, sp, stp, ss, es); |
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| 443 | assert(rest != NULL); /* it did match */ |
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| 444 | /* could the rest match the rest? */ |
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| 445 | tail = slow(m, rest, stop, es, stopst); |
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| 446 | if (tail == stop) |
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| 447 | break; /* yes! */ |
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| 448 | /* no -- try a shorter match for this one */ |
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| 449 | stp = rest - 1; |
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| 450 | assert(stp >= sp); /* it did work */ |
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| 451 | } |
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| 452 | ssub = ss + 1; |
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| 453 | esub = es - 1; |
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| 454 | ssp = sp; |
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| 455 | oldssp = ssp; |
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| 456 | for (;;) { /* find last match of innards */ |
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| 457 | sep = slow(m, ssp, rest, ssub, esub); |
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| 458 | if (sep == NULL || sep == ssp) |
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| 459 | break; /* failed or matched null */ |
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| 460 | oldssp = ssp; /* on to next try */ |
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| 461 | ssp = sep; |
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| 462 | } |
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| 463 | if (sep == NULL) { |
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| 464 | /* last successful match */ |
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| 465 | sep = ssp; |
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| 466 | ssp = oldssp; |
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| 467 | } |
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| 468 | assert(sep == rest); /* must exhaust substring */ |
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| 469 | assert(slow(m, ssp, sep, ssub, esub) == rest); |
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| 470 | dp = dissect(m, ssp, sep, ssub, esub); |
---|
| 471 | assert(dp == sep); |
---|
| 472 | sp = rest; |
---|
| 473 | break; |
---|
| 474 | case OCH_: |
---|
| 475 | stp = stop; |
---|
| 476 | for (;;) { |
---|
| 477 | /* how long could this one be? */ |
---|
| 478 | rest = slow(m, sp, stp, ss, es); |
---|
| 479 | assert(rest != NULL); /* it did match */ |
---|
| 480 | /* could the rest match the rest? */ |
---|
| 481 | tail = slow(m, rest, stop, es, stopst); |
---|
| 482 | if (tail == stop) |
---|
| 483 | break; /* yes! */ |
---|
| 484 | /* no -- try a shorter match for this one */ |
---|
| 485 | stp = rest - 1; |
---|
| 486 | assert(stp >= sp); /* it did work */ |
---|
| 487 | } |
---|
| 488 | ssub = ss + 1; |
---|
| 489 | esub = ss + OPND(m->g->strip[ss]) - 1; |
---|
| 490 | assert(OP(m->g->strip[esub]) == OOR1); |
---|
| 491 | for (;;) { /* find first matching branch */ |
---|
| 492 | if (slow(m, sp, rest, ssub, esub) == rest) |
---|
| 493 | break; /* it matched all of it */ |
---|
| 494 | /* that one missed, try next one */ |
---|
| 495 | assert(OP(m->g->strip[esub]) == OOR1); |
---|
| 496 | esub++; |
---|
| 497 | assert(OP(m->g->strip[esub]) == OOR2); |
---|
| 498 | ssub = esub + 1; |
---|
| 499 | esub += OPND(m->g->strip[esub]); |
---|
| 500 | if (OP(m->g->strip[esub]) == OOR2) |
---|
| 501 | esub--; |
---|
| 502 | else |
---|
| 503 | assert(OP(m->g->strip[esub]) == O_CH); |
---|
| 504 | } |
---|
| 505 | dp = dissect(m, sp, rest, ssub, esub); |
---|
| 506 | assert(dp == rest); |
---|
| 507 | sp = rest; |
---|
| 508 | break; |
---|
| 509 | case O_PLUS: |
---|
| 510 | case O_QUEST: |
---|
| 511 | case OOR1: |
---|
| 512 | case OOR2: |
---|
| 513 | case O_CH: |
---|
| 514 | assert(nope); |
---|
| 515 | break; |
---|
| 516 | case OLPAREN: |
---|
| 517 | i = OPND(m->g->strip[ss]); |
---|
| 518 | assert(0 < i && i <= m->g->nsub); |
---|
| 519 | m->pmatch[i].rm_so = sp - m->offp; |
---|
| 520 | break; |
---|
| 521 | case ORPAREN: |
---|
| 522 | i = OPND(m->g->strip[ss]); |
---|
| 523 | assert(0 < i && i <= m->g->nsub); |
---|
| 524 | m->pmatch[i].rm_eo = sp - m->offp; |
---|
| 525 | break; |
---|
| 526 | default: /* uh oh */ |
---|
| 527 | assert(nope); |
---|
| 528 | break; |
---|
| 529 | } |
---|
| 530 | } |
---|
| 531 | |
---|
| 532 | assert(sp == stop); |
---|
| 533 | return(sp); |
---|
| 534 | } |
---|
| 535 | |
---|
| 536 | /* |
---|
| 537 | - backref - figure out what matched what, figuring in back references |
---|
| 538 | == static char *backref(struct match *m, char *start, \ |
---|
| 539 | == char *stop, sopno startst, sopno stopst, sopno lev); |
---|
| 540 | */ |
---|
| 541 | static char * /* == stop (success) or NULL (failure) */ |
---|
| 542 | backref(m, start, stop, startst, stopst, lev) |
---|
| 543 | struct match *m; |
---|
| 544 | char *start; |
---|
| 545 | char *stop; |
---|
| 546 | sopno startst; |
---|
| 547 | sopno stopst; |
---|
| 548 | sopno lev; /* PLUS nesting level */ |
---|
| 549 | { |
---|
| 550 | int i; |
---|
| 551 | sopno ss; /* start sop of current subRE */ |
---|
| 552 | char *sp; /* start of string matched by it */ |
---|
| 553 | sopno ssub; /* start sop of subsubRE */ |
---|
| 554 | sopno esub; /* end sop of subsubRE */ |
---|
| 555 | char *ssp; /* start of string matched by subsubRE */ |
---|
| 556 | char *dp; |
---|
| 557 | size_t len; |
---|
| 558 | int hard; |
---|
| 559 | sop s; |
---|
| 560 | regoff_t offsave; |
---|
| 561 | cset *cs; |
---|
| 562 | |
---|
| 563 | AT("back", start, stop, startst, stopst); |
---|
| 564 | sp = start; |
---|
| 565 | |
---|
| 566 | /* get as far as we can with easy stuff */ |
---|
| 567 | hard = 0; |
---|
| 568 | for (ss = startst; !hard && ss < stopst; ss++) |
---|
| 569 | switch (OP(s = m->g->strip[ss])) { |
---|
| 570 | case OCHAR: |
---|
| 571 | if (sp == stop || *sp++ != (char)OPND(s)) |
---|
| 572 | return(NULL); |
---|
| 573 | break; |
---|
| 574 | case OANY: |
---|
| 575 | if (sp == stop) |
---|
| 576 | return(NULL); |
---|
| 577 | sp++; |
---|
| 578 | break; |
---|
| 579 | case OANYOF: |
---|
| 580 | cs = &m->g->sets[OPND(s)]; |
---|
| 581 | if (sp == stop || !CHIN(cs, *sp++)) |
---|
| 582 | return(NULL); |
---|
| 583 | break; |
---|
| 584 | case OBOL: |
---|
| 585 | if ( (sp == m->beginp && !(m->eflags®_NOTBOL)) || |
---|
| 586 | (sp < m->endp && *(sp-1) == '\n' && |
---|
| 587 | (m->g->cflags®_NEWLINE)) ) |
---|
| 588 | { /* yes */ } |
---|
| 589 | else |
---|
| 590 | return(NULL); |
---|
| 591 | break; |
---|
| 592 | case OEOL: |
---|
| 593 | if ( (sp == m->endp && !(m->eflags®_NOTEOL)) || |
---|
| 594 | (sp < m->endp && *sp == '\n' && |
---|
| 595 | (m->g->cflags®_NEWLINE)) ) |
---|
| 596 | { /* yes */ } |
---|
| 597 | else |
---|
| 598 | return(NULL); |
---|
| 599 | break; |
---|
| 600 | case OBOW: |
---|
| 601 | if (( (sp == m->beginp && !(m->eflags®_NOTBOL)) || |
---|
| 602 | (sp < m->endp && *(sp-1) == '\n' && |
---|
| 603 | (m->g->cflags®_NEWLINE)) || |
---|
| 604 | (sp > m->beginp && |
---|
| 605 | !ISWORD(*(sp-1))) ) && |
---|
| 606 | (sp < m->endp && ISWORD(*sp)) ) |
---|
| 607 | { /* yes */ } |
---|
| 608 | else |
---|
| 609 | return(NULL); |
---|
| 610 | break; |
---|
| 611 | case OEOW: |
---|
| 612 | if (( (sp == m->endp && !(m->eflags®_NOTEOL)) || |
---|
| 613 | (sp < m->endp && *sp == '\n' && |
---|
| 614 | (m->g->cflags®_NEWLINE)) || |
---|
| 615 | (sp < m->endp && !ISWORD(*sp)) ) && |
---|
| 616 | (sp > m->beginp && ISWORD(*(sp-1))) ) |
---|
| 617 | { /* yes */ } |
---|
| 618 | else |
---|
| 619 | return(NULL); |
---|
| 620 | break; |
---|
| 621 | case O_QUEST: |
---|
| 622 | break; |
---|
| 623 | case OOR1: /* matches null but needs to skip */ |
---|
| 624 | ss++; |
---|
| 625 | s = m->g->strip[ss]; |
---|
| 626 | do { |
---|
| 627 | assert(OP(s) == OOR2); |
---|
| 628 | ss += OPND(s); |
---|
| 629 | } while (OP(s = m->g->strip[ss]) != O_CH); |
---|
| 630 | /* note that the ss++ gets us past the O_CH */ |
---|
| 631 | break; |
---|
| 632 | default: /* have to make a choice */ |
---|
| 633 | hard = 1; |
---|
| 634 | break; |
---|
| 635 | } |
---|
| 636 | if (!hard) { /* that was it! */ |
---|
| 637 | if (sp != stop) |
---|
| 638 | return(NULL); |
---|
| 639 | return(sp); |
---|
| 640 | } |
---|
| 641 | ss--; /* adjust for the for's final increment */ |
---|
| 642 | |
---|
| 643 | /* the hard stuff */ |
---|
| 644 | AT("hard", sp, stop, ss, stopst); |
---|
| 645 | s = m->g->strip[ss]; |
---|
| 646 | switch (OP(s)) { |
---|
| 647 | case OBACK_: /* the vilest depths */ |
---|
| 648 | i = OPND(s); |
---|
| 649 | assert(0 < i && i <= m->g->nsub); |
---|
| 650 | if (m->pmatch[i].rm_eo == -1) |
---|
| 651 | return(NULL); |
---|
| 652 | assert(m->pmatch[i].rm_so != -1); |
---|
| 653 | len = m->pmatch[i].rm_eo - m->pmatch[i].rm_so; |
---|
| 654 | assert(stop - m->beginp >= len); |
---|
| 655 | if (sp > stop - len) |
---|
| 656 | return(NULL); /* not enough left to match */ |
---|
| 657 | ssp = m->offp + m->pmatch[i].rm_so; |
---|
| 658 | if (memcmp(sp, ssp, len) != 0) |
---|
| 659 | return(NULL); |
---|
| 660 | while (m->g->strip[ss] != SOP(O_BACK, i)) |
---|
| 661 | ss++; |
---|
| 662 | return(backref(m, sp+len, stop, ss+1, stopst, lev)); |
---|
| 663 | break; |
---|
| 664 | case OQUEST_: /* to null or not */ |
---|
| 665 | dp = backref(m, sp, stop, ss+1, stopst, lev); |
---|
| 666 | if (dp != NULL) |
---|
| 667 | return(dp); /* not */ |
---|
| 668 | return(backref(m, sp, stop, ss+OPND(s)+1, stopst, lev)); |
---|
| 669 | break; |
---|
| 670 | case OPLUS_: |
---|
| 671 | assert(m->lastpos != NULL); |
---|
| 672 | assert(lev+1 <= m->g->nplus); |
---|
| 673 | m->lastpos[lev+1] = sp; |
---|
| 674 | return(backref(m, sp, stop, ss+1, stopst, lev+1)); |
---|
| 675 | break; |
---|
| 676 | case O_PLUS: |
---|
| 677 | if (sp == m->lastpos[lev]) /* last pass matched null */ |
---|
| 678 | return(backref(m, sp, stop, ss+1, stopst, lev-1)); |
---|
| 679 | /* try another pass */ |
---|
| 680 | m->lastpos[lev] = sp; |
---|
| 681 | dp = backref(m, sp, stop, ss-OPND(s)+1, stopst, lev); |
---|
| 682 | if (dp == NULL) |
---|
| 683 | return(backref(m, sp, stop, ss+1, stopst, lev-1)); |
---|
| 684 | else |
---|
| 685 | return(dp); |
---|
| 686 | break; |
---|
| 687 | case OCH_: /* find the right one, if any */ |
---|
| 688 | ssub = ss + 1; |
---|
| 689 | esub = ss + OPND(s) - 1; |
---|
| 690 | assert(OP(m->g->strip[esub]) == OOR1); |
---|
| 691 | for (;;) { /* find first matching branch */ |
---|
| 692 | dp = backref(m, sp, stop, ssub, esub, lev); |
---|
| 693 | if (dp != NULL) |
---|
| 694 | return(dp); |
---|
| 695 | /* that one missed, try next one */ |
---|
| 696 | if (OP(m->g->strip[esub]) == O_CH) |
---|
| 697 | return(NULL); /* there is none */ |
---|
| 698 | esub++; |
---|
| 699 | assert(OP(m->g->strip[esub]) == OOR2); |
---|
| 700 | ssub = esub + 1; |
---|
| 701 | esub += OPND(m->g->strip[esub]); |
---|
| 702 | if (OP(m->g->strip[esub]) == OOR2) |
---|
| 703 | esub--; |
---|
| 704 | else |
---|
| 705 | assert(OP(m->g->strip[esub]) == O_CH); |
---|
| 706 | } |
---|
| 707 | break; |
---|
| 708 | case OLPAREN: /* must undo assignment if rest fails */ |
---|
| 709 | i = OPND(s); |
---|
| 710 | assert(0 < i && i <= m->g->nsub); |
---|
| 711 | offsave = m->pmatch[i].rm_so; |
---|
| 712 | m->pmatch[i].rm_so = sp - m->offp; |
---|
| 713 | dp = backref(m, sp, stop, ss+1, stopst, lev); |
---|
| 714 | if (dp != NULL) |
---|
| 715 | return(dp); |
---|
| 716 | m->pmatch[i].rm_so = offsave; |
---|
| 717 | return(NULL); |
---|
| 718 | break; |
---|
| 719 | case ORPAREN: /* must undo assignment if rest fails */ |
---|
| 720 | i = OPND(s); |
---|
| 721 | assert(0 < i && i <= m->g->nsub); |
---|
| 722 | offsave = m->pmatch[i].rm_eo; |
---|
| 723 | m->pmatch[i].rm_eo = sp - m->offp; |
---|
| 724 | dp = backref(m, sp, stop, ss+1, stopst, lev); |
---|
| 725 | if (dp != NULL) |
---|
| 726 | return(dp); |
---|
| 727 | m->pmatch[i].rm_eo = offsave; |
---|
| 728 | return(NULL); |
---|
| 729 | break; |
---|
| 730 | default: /* uh oh */ |
---|
| 731 | assert(nope); |
---|
| 732 | break; |
---|
| 733 | } |
---|
| 734 | |
---|
| 735 | /* "can't happen" */ |
---|
| 736 | assert(nope); |
---|
| 737 | /* NOTREACHED */ |
---|
| 738 | return "shut up gcc"; |
---|
| 739 | } |
---|
| 740 | |
---|
| 741 | /* |
---|
| 742 | - fast - step through the string at top speed |
---|
| 743 | == static char *fast(struct match *m, char *start, \ |
---|
| 744 | == char *stop, sopno startst, sopno stopst); |
---|
| 745 | */ |
---|
| 746 | static char * /* where tentative match ended, or NULL */ |
---|
| 747 | fast(m, start, stop, startst, stopst) |
---|
| 748 | struct match *m; |
---|
| 749 | char *start; |
---|
| 750 | char *stop; |
---|
| 751 | sopno startst; |
---|
| 752 | sopno stopst; |
---|
| 753 | { |
---|
| 754 | states st = m->st; |
---|
| 755 | states fresh = m->fresh; |
---|
| 756 | states tmp = m->tmp; |
---|
| 757 | char *p = start; |
---|
| 758 | int c = (start == m->beginp) ? OUT : *(start-1); |
---|
| 759 | int lastc; /* previous c */ |
---|
| 760 | int flagch; |
---|
| 761 | int i; |
---|
| 762 | char *coldp; /* last p after which no match was underway */ |
---|
| 763 | |
---|
| 764 | CLEAR(st); |
---|
| 765 | SET1(st, startst); |
---|
| 766 | st = step(m->g, startst, stopst, st, NOTHING, st); |
---|
| 767 | ASSIGN(fresh, st); |
---|
| 768 | SP("start", st, *p); |
---|
| 769 | coldp = NULL; |
---|
| 770 | for (;;) { |
---|
| 771 | /* next character */ |
---|
| 772 | lastc = c; |
---|
| 773 | c = (p == m->endp) ? OUT : *p; |
---|
| 774 | if (EQ(st, fresh)) |
---|
| 775 | coldp = p; |
---|
| 776 | |
---|
| 777 | /* is there an EOL and/or BOL between lastc and c? */ |
---|
| 778 | flagch = '\0'; |
---|
| 779 | i = 0; |
---|
| 780 | if ( (lastc == '\n' && m->g->cflags®_NEWLINE) || |
---|
| 781 | (lastc == OUT && !(m->eflags®_NOTBOL)) ) { |
---|
| 782 | flagch = BOL; |
---|
| 783 | i = m->g->nbol; |
---|
| 784 | } |
---|
| 785 | if ( (c == '\n' && m->g->cflags®_NEWLINE) || |
---|
| 786 | (c == OUT && !(m->eflags®_NOTEOL)) ) { |
---|
| 787 | flagch = (flagch == BOL) ? BOLEOL : EOL; |
---|
| 788 | i += m->g->neol; |
---|
| 789 | } |
---|
| 790 | if (i != 0) { |
---|
| 791 | for (; i > 0; i--) |
---|
| 792 | st = step(m->g, startst, stopst, st, flagch, st); |
---|
| 793 | SP("boleol", st, c); |
---|
| 794 | } |
---|
| 795 | |
---|
| 796 | /* how about a word boundary? */ |
---|
| 797 | if ( (flagch == BOL || (lastc != OUT && !ISWORD(lastc))) && |
---|
| 798 | (c != OUT && ISWORD(c)) ) { |
---|
| 799 | flagch = BOW; |
---|
| 800 | } |
---|
| 801 | if ( (lastc != OUT && ISWORD(lastc)) && |
---|
| 802 | (flagch == EOL || (c != OUT && !ISWORD(c))) ) { |
---|
| 803 | flagch = EOW; |
---|
| 804 | } |
---|
| 805 | if (flagch == BOW || flagch == EOW) { |
---|
| 806 | st = step(m->g, startst, stopst, st, flagch, st); |
---|
| 807 | SP("boweow", st, c); |
---|
| 808 | } |
---|
| 809 | |
---|
| 810 | /* are we done? */ |
---|
| 811 | if (ISSET(st, stopst) || p == stop) |
---|
| 812 | break; /* NOTE BREAK OUT */ |
---|
| 813 | |
---|
| 814 | /* no, we must deal with this character */ |
---|
| 815 | ASSIGN(tmp, st); |
---|
| 816 | ASSIGN(st, fresh); |
---|
| 817 | assert(c != OUT); |
---|
| 818 | st = step(m->g, startst, stopst, tmp, c, st); |
---|
| 819 | SP("aft", st, c); |
---|
| 820 | assert(EQ(step(m->g, startst, stopst, st, NOTHING, st), st)); |
---|
| 821 | p++; |
---|
| 822 | } |
---|
| 823 | |
---|
| 824 | assert(coldp != NULL); |
---|
| 825 | m->coldp = coldp; |
---|
| 826 | if (ISSET(st, stopst)) |
---|
| 827 | return(p+1); |
---|
| 828 | else |
---|
| 829 | return(NULL); |
---|
| 830 | } |
---|
| 831 | |
---|
| 832 | /* |
---|
| 833 | - slow - step through the string more deliberately |
---|
| 834 | == static char *slow(struct match *m, char *start, \ |
---|
| 835 | == char *stop, sopno startst, sopno stopst); |
---|
| 836 | */ |
---|
| 837 | static char * /* where it ended */ |
---|
| 838 | slow(m, start, stop, startst, stopst) |
---|
| 839 | struct match *m; |
---|
| 840 | char *start; |
---|
| 841 | char *stop; |
---|
| 842 | sopno startst; |
---|
| 843 | sopno stopst; |
---|
| 844 | { |
---|
| 845 | states st = m->st; |
---|
| 846 | states empty = m->empty; |
---|
| 847 | states tmp = m->tmp; |
---|
| 848 | char *p = start; |
---|
| 849 | int c = (start == m->beginp) ? OUT : *(start-1); |
---|
| 850 | int lastc; /* previous c */ |
---|
| 851 | int flagch; |
---|
| 852 | int i; |
---|
| 853 | char *matchp; /* last p at which a match ended */ |
---|
| 854 | |
---|
| 855 | AT("slow", start, stop, startst, stopst); |
---|
| 856 | CLEAR(st); |
---|
| 857 | SET1(st, startst); |
---|
| 858 | SP("sstart", st, *p); |
---|
| 859 | st = step(m->g, startst, stopst, st, NOTHING, st); |
---|
| 860 | matchp = NULL; |
---|
| 861 | for (;;) { |
---|
| 862 | /* next character */ |
---|
| 863 | lastc = c; |
---|
| 864 | c = (p == m->endp) ? OUT : *p; |
---|
| 865 | |
---|
| 866 | /* is there an EOL and/or BOL between lastc and c? */ |
---|
| 867 | flagch = '\0'; |
---|
| 868 | i = 0; |
---|
| 869 | if ( (lastc == '\n' && m->g->cflags®_NEWLINE) || |
---|
| 870 | (lastc == OUT && !(m->eflags®_NOTBOL)) ) { |
---|
| 871 | flagch = BOL; |
---|
| 872 | i = m->g->nbol; |
---|
| 873 | } |
---|
| 874 | if ( (c == '\n' && m->g->cflags®_NEWLINE) || |
---|
| 875 | (c == OUT && !(m->eflags®_NOTEOL)) ) { |
---|
| 876 | flagch = (flagch == BOL) ? BOLEOL : EOL; |
---|
| 877 | i += m->g->neol; |
---|
| 878 | } |
---|
| 879 | if (i != 0) { |
---|
| 880 | for (; i > 0; i--) |
---|
| 881 | st = step(m->g, startst, stopst, st, flagch, st); |
---|
| 882 | SP("sboleol", st, c); |
---|
| 883 | } |
---|
| 884 | |
---|
| 885 | /* how about a word boundary? */ |
---|
| 886 | if ( (flagch == BOL || (lastc != OUT && !ISWORD(lastc))) && |
---|
| 887 | (c != OUT && ISWORD(c)) ) { |
---|
| 888 | flagch = BOW; |
---|
| 889 | } |
---|
| 890 | if ( (lastc != OUT && ISWORD(lastc)) && |
---|
| 891 | (flagch == EOL || (c != OUT && !ISWORD(c))) ) { |
---|
| 892 | flagch = EOW; |
---|
| 893 | } |
---|
| 894 | if (flagch == BOW || flagch == EOW) { |
---|
| 895 | st = step(m->g, startst, stopst, st, flagch, st); |
---|
| 896 | SP("sboweow", st, c); |
---|
| 897 | } |
---|
| 898 | |
---|
| 899 | /* are we done? */ |
---|
| 900 | if (ISSET(st, stopst)) |
---|
| 901 | matchp = p; |
---|
| 902 | if (EQ(st, empty) || p == stop) |
---|
| 903 | break; /* NOTE BREAK OUT */ |
---|
| 904 | |
---|
| 905 | /* no, we must deal with this character */ |
---|
| 906 | ASSIGN(tmp, st); |
---|
| 907 | ASSIGN(st, empty); |
---|
| 908 | assert(c != OUT); |
---|
| 909 | st = step(m->g, startst, stopst, tmp, c, st); |
---|
| 910 | SP("saft", st, c); |
---|
| 911 | assert(EQ(step(m->g, startst, stopst, st, NOTHING, st), st)); |
---|
| 912 | p++; |
---|
| 913 | } |
---|
| 914 | |
---|
| 915 | return(matchp); |
---|
| 916 | } |
---|
| 917 | |
---|
| 918 | |
---|
| 919 | /* |
---|
| 920 | - step - map set of states reachable before char to set reachable after |
---|
| 921 | == static states step(struct re_guts *g, sopno start, sopno stop, \ |
---|
| 922 | == states bef, int ch, states aft); |
---|
| 923 | == #define BOL (OUT+1) |
---|
| 924 | == #define EOL (BOL+1) |
---|
| 925 | == #define BOLEOL (BOL+2) |
---|
| 926 | == #define NOTHING (BOL+3) |
---|
| 927 | == #define BOW (BOL+4) |
---|
| 928 | == #define EOW (BOL+5) |
---|
| 929 | == #define CODEMAX (BOL+5) // highest code used |
---|
| 930 | == #define NONCHAR(c) ((c) > CHAR_MAX) |
---|
| 931 | == #define NNONCHAR (CODEMAX-CHAR_MAX) |
---|
| 932 | */ |
---|
| 933 | static states |
---|
| 934 | step(g, start, stop, bef, ch, aft) |
---|
| 935 | struct re_guts *g; |
---|
| 936 | sopno start; /* start state within strip */ |
---|
| 937 | sopno stop; /* state after stop state within strip */ |
---|
| 938 | states bef; /* states reachable before */ |
---|
| 939 | int ch; /* character or NONCHAR code */ |
---|
| 940 | states aft; /* states already known reachable after */ |
---|
| 941 | { |
---|
| 942 | cset *cs; |
---|
| 943 | sop s; |
---|
| 944 | sopno pc; |
---|
| 945 | onestate here; /* note, macros know this name */ |
---|
| 946 | sopno look; |
---|
| 947 | int i; |
---|
| 948 | |
---|
| 949 | for (pc = start, INIT(here, pc); pc != stop; pc++, INC(here)) { |
---|
| 950 | s = g->strip[pc]; |
---|
| 951 | switch (OP(s)) { |
---|
| 952 | case OEND: |
---|
| 953 | assert(pc == stop-1); |
---|
| 954 | break; |
---|
| 955 | case OCHAR: |
---|
| 956 | /* only characters can match */ |
---|
| 957 | assert(!NONCHAR(ch) || ch != (char)OPND(s)); |
---|
| 958 | if (ch == (char)OPND(s)) |
---|
| 959 | FWD(aft, bef, 1); |
---|
| 960 | break; |
---|
| 961 | case OBOL: |
---|
| 962 | if (ch == BOL || ch == BOLEOL) |
---|
| 963 | FWD(aft, bef, 1); |
---|
| 964 | break; |
---|
| 965 | case OEOL: |
---|
| 966 | if (ch == EOL || ch == BOLEOL) |
---|
| 967 | FWD(aft, bef, 1); |
---|
| 968 | break; |
---|
| 969 | case OBOW: |
---|
| 970 | if (ch == BOW) |
---|
| 971 | FWD(aft, bef, 1); |
---|
| 972 | break; |
---|
| 973 | case OEOW: |
---|
| 974 | if (ch == EOW) |
---|
| 975 | FWD(aft, bef, 1); |
---|
| 976 | break; |
---|
| 977 | case OANY: |
---|
| 978 | if (!NONCHAR(ch)) |
---|
| 979 | FWD(aft, bef, 1); |
---|
| 980 | break; |
---|
| 981 | case OANYOF: |
---|
| 982 | cs = &g->sets[OPND(s)]; |
---|
| 983 | if (!NONCHAR(ch) && CHIN(cs, ch)) |
---|
| 984 | FWD(aft, bef, 1); |
---|
| 985 | break; |
---|
| 986 | case OBACK_: /* ignored here */ |
---|
| 987 | case O_BACK: |
---|
| 988 | FWD(aft, aft, 1); |
---|
| 989 | break; |
---|
| 990 | case OPLUS_: /* forward, this is just an empty */ |
---|
| 991 | FWD(aft, aft, 1); |
---|
| 992 | break; |
---|
| 993 | case O_PLUS: /* both forward and back */ |
---|
| 994 | FWD(aft, aft, 1); |
---|
| 995 | i = ISSETBACK(aft, OPND(s)); |
---|
| 996 | BACK(aft, aft, OPND(s)); |
---|
| 997 | if (!i && ISSETBACK(aft, OPND(s))) { |
---|
| 998 | /* oho, must reconsider loop body */ |
---|
| 999 | pc -= OPND(s) + 1; |
---|
| 1000 | INIT(here, pc); |
---|
| 1001 | } |
---|
| 1002 | break; |
---|
| 1003 | case OQUEST_: /* two branches, both forward */ |
---|
| 1004 | FWD(aft, aft, 1); |
---|
| 1005 | FWD(aft, aft, OPND(s)); |
---|
| 1006 | break; |
---|
| 1007 | case O_QUEST: /* just an empty */ |
---|
| 1008 | FWD(aft, aft, 1); |
---|
| 1009 | break; |
---|
| 1010 | case OLPAREN: /* not significant here */ |
---|
| 1011 | case ORPAREN: |
---|
| 1012 | FWD(aft, aft, 1); |
---|
| 1013 | break; |
---|
| 1014 | case OCH_: /* mark the first two branches */ |
---|
| 1015 | FWD(aft, aft, 1); |
---|
| 1016 | assert(OP(g->strip[pc+OPND(s)]) == OOR2); |
---|
| 1017 | FWD(aft, aft, OPND(s)); |
---|
| 1018 | break; |
---|
| 1019 | case OOR1: /* done a branch, find the O_CH */ |
---|
| 1020 | if (ISSTATEIN(aft, here)) { |
---|
| 1021 | for (look = 1; |
---|
| 1022 | OP(s = g->strip[pc+look]) != O_CH; |
---|
| 1023 | look += OPND(s)) |
---|
| 1024 | assert(OP(s) == OOR2); |
---|
| 1025 | FWD(aft, aft, look); |
---|
| 1026 | } |
---|
| 1027 | break; |
---|
| 1028 | case OOR2: /* propagate OCH_'s marking */ |
---|
| 1029 | FWD(aft, aft, 1); |
---|
| 1030 | if (OP(g->strip[pc+OPND(s)]) != O_CH) { |
---|
| 1031 | assert(OP(g->strip[pc+OPND(s)]) == OOR2); |
---|
| 1032 | FWD(aft, aft, OPND(s)); |
---|
| 1033 | } |
---|
| 1034 | break; |
---|
| 1035 | case O_CH: /* just empty */ |
---|
| 1036 | FWD(aft, aft, 1); |
---|
| 1037 | break; |
---|
| 1038 | default: /* ooooops... */ |
---|
| 1039 | assert(nope); |
---|
| 1040 | break; |
---|
| 1041 | } |
---|
| 1042 | } |
---|
| 1043 | |
---|
| 1044 | return(aft); |
---|
| 1045 | } |
---|
| 1046 | |
---|
| 1047 | #ifdef REDEBUG |
---|
| 1048 | /* |
---|
| 1049 | - print - print a set of states |
---|
| 1050 | == #ifdef REDEBUG |
---|
| 1051 | == static void print(struct match *m, char *caption, states st, \ |
---|
| 1052 | == int ch, FILE *d); |
---|
| 1053 | == #endif |
---|
| 1054 | */ |
---|
| 1055 | static void |
---|
| 1056 | print(m, caption, st, ch, d) |
---|
| 1057 | struct match *m; |
---|
| 1058 | char *caption; |
---|
| 1059 | states st; |
---|
| 1060 | int ch; |
---|
| 1061 | FILE *d; |
---|
| 1062 | { |
---|
| 1063 | struct re_guts *g = m->g; |
---|
| 1064 | int i; |
---|
| 1065 | int first = 1; |
---|
| 1066 | |
---|
| 1067 | if (!(m->eflags®_TRACE)) |
---|
| 1068 | return; |
---|
| 1069 | |
---|
| 1070 | fprintf(d, "%s", caption); |
---|
| 1071 | if (ch != '\0') |
---|
| 1072 | fprintf(d, " %s", pchar(ch)); |
---|
| 1073 | for (i = 0; i < g->nstates; i++) |
---|
| 1074 | if (ISSET(st, i)) { |
---|
| 1075 | fprintf(d, "%s%d", (first) ? "\t" : ", ", i); |
---|
| 1076 | first = 0; |
---|
| 1077 | } |
---|
| 1078 | fprintf(d, "\n"); |
---|
| 1079 | } |
---|
| 1080 | |
---|
| 1081 | /* |
---|
| 1082 | - at - print current situation |
---|
| 1083 | == #ifdef REDEBUG |
---|
| 1084 | == static void at(struct match *m, char *title, char *start, char *stop, \ |
---|
| 1085 | == sopno startst, sopno stopst); |
---|
| 1086 | == #endif |
---|
| 1087 | */ |
---|
| 1088 | static void |
---|
| 1089 | at(m, title, start, stop, startst, stopst) |
---|
| 1090 | struct match *m; |
---|
| 1091 | char *title; |
---|
| 1092 | char *start; |
---|
| 1093 | char *stop; |
---|
| 1094 | sopno startst; |
---|
| 1095 | sopno stopst; |
---|
| 1096 | { |
---|
| 1097 | if (!(m->eflags®_TRACE)) |
---|
| 1098 | return; |
---|
| 1099 | |
---|
| 1100 | printf("%s %s-", title, pchar(*start)); |
---|
| 1101 | printf("%s ", pchar(*stop)); |
---|
| 1102 | printf("%ld-%ld\n", (long)startst, (long)stopst); |
---|
| 1103 | } |
---|
| 1104 | |
---|
| 1105 | #ifndef PCHARDONE |
---|
| 1106 | #define PCHARDONE /* never again */ |
---|
| 1107 | /* |
---|
| 1108 | - pchar - make a character printable |
---|
| 1109 | == #ifdef REDEBUG |
---|
| 1110 | == static char *pchar(int ch); |
---|
| 1111 | == #endif |
---|
| 1112 | * |
---|
| 1113 | * Is this identical to regchar() over in debug.c? Well, yes. But a |
---|
| 1114 | * duplicate here avoids having a debugging-capable regexec.o tied to |
---|
| 1115 | * a matching debug.o, and this is convenient. It all disappears in |
---|
| 1116 | * the non-debug compilation anyway, so it doesn't matter much. |
---|
| 1117 | */ |
---|
| 1118 | static char * /* -> representation */ |
---|
| 1119 | pchar(ch) |
---|
| 1120 | int ch; |
---|
| 1121 | { |
---|
| 1122 | static char pbuf[10]; |
---|
| 1123 | |
---|
| 1124 | if (isprint((uch)ch) || ch == ' ') |
---|
| 1125 | sprintf(pbuf, "%c", ch); |
---|
| 1126 | else |
---|
| 1127 | sprintf(pbuf, "\\%o", ch); |
---|
| 1128 | return(pbuf); |
---|
| 1129 | } |
---|
| 1130 | #endif |
---|
| 1131 | #endif |
---|
| 1132 | |
---|
| 1133 | #undef matcher |
---|
| 1134 | #undef fast |
---|
| 1135 | #undef slow |
---|
| 1136 | #undef dissect |
---|
| 1137 | #undef backref |
---|
| 1138 | #undef step |
---|
| 1139 | #undef print |
---|
| 1140 | #undef at |
---|
| 1141 | #undef match |
---|