[25] | 1 | /* |
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| 2 | * re_*exec and friends - match REs |
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| 3 | * |
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| 4 | * Copyright (c) 1998, 1999 Henry Spencer. All rights reserved. |
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| 5 | * |
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| 6 | * Development of this software was funded, in part, by Cray Research Inc., |
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| 7 | * UUNET Communications Services Inc., Sun Microsystems Inc., and Scriptics |
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| 8 | * Corporation, none of whom are responsible for the results. The author |
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| 9 | * thanks all of them. |
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| 10 | * |
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| 11 | * Redistribution and use in source and binary forms -- with or without |
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| 12 | * modification -- are permitted for any purpose, provided that |
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| 13 | * redistributions in source form retain this entire copyright notice and |
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| 14 | * indicate the origin and nature of any modifications. |
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| 15 | * |
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| 16 | * I'd appreciate being given credit for this package in the documentation of |
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| 17 | * software which uses it, but that is not a requirement. |
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| 18 | * |
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| 19 | * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, |
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| 20 | * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY |
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| 21 | * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL |
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| 22 | * HENRY SPENCER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
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| 23 | * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
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| 24 | * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; |
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| 25 | * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, |
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| 26 | * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR |
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| 27 | * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
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| 28 | * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
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| 29 | */ |
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| 30 | |
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| 31 | #include "regguts.h" |
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| 32 | |
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| 33 | /* |
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| 34 | * Lazy-DFA representation. |
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| 35 | */ |
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| 36 | |
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| 37 | struct arcp { /* "pointer" to an outarc */ |
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| 38 | struct sset *ss; |
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| 39 | color co; |
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| 40 | }; |
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| 41 | |
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| 42 | struct sset { /* state set */ |
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| 43 | unsigned *states; /* pointer to bitvector */ |
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| 44 | unsigned hash; /* hash of bitvector */ |
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| 45 | #define HASH(bv, nw) (((nw) == 1) ? *(bv) : hash(bv, nw)) |
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| 46 | #define HIT(h,bv,ss,nw) ((ss)->hash == (h) && ((nw) == 1 || \ |
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| 47 | memcmp(VS(bv), VS((ss)->states), (nw)*sizeof(unsigned)) == 0)) |
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| 48 | int flags; |
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| 49 | #define STARTER 01 /* the initial state set */ |
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| 50 | #define POSTSTATE 02 /* includes the goal state */ |
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| 51 | #define LOCKED 04 /* locked in cache */ |
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| 52 | #define NOPROGRESS 010 /* zero-progress state set */ |
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| 53 | struct arcp ins; /* chain of inarcs pointing here */ |
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| 54 | chr *lastseen; /* last entered on arrival here */ |
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| 55 | struct sset **outs; /* outarc vector indexed by color */ |
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| 56 | struct arcp *inchain; /* chain-pointer vector for outarcs */ |
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| 57 | }; |
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| 58 | |
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| 59 | struct dfa { |
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| 60 | int nssets; /* size of cache */ |
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| 61 | int nssused; /* how many entries occupied yet */ |
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| 62 | int nstates; /* number of states */ |
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| 63 | int ncolors; /* length of outarc and inchain vectors */ |
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| 64 | int wordsper; /* length of state-set bitvectors */ |
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| 65 | struct sset *ssets; /* state-set cache */ |
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| 66 | unsigned *statesarea; /* bitvector storage */ |
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| 67 | unsigned *work; /* pointer to work area within statesarea */ |
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| 68 | struct sset **outsarea; /* outarc-vector storage */ |
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| 69 | struct arcp *incarea; /* inchain storage */ |
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| 70 | struct cnfa *cnfa; |
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| 71 | struct colormap *cm; |
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| 72 | chr *lastpost; /* location of last cache-flushed success */ |
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| 73 | chr *lastnopr; /* location of last cache-flushed NOPROGRESS */ |
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| 74 | struct sset *search; /* replacement-search-pointer memory */ |
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| 75 | int cptsmalloced; /* were the areas individually malloced? */ |
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| 76 | char *mallocarea; /* self, or master malloced area, or NULL */ |
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| 77 | }; |
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| 78 | |
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| 79 | #define WORK 1 /* number of work bitvectors needed */ |
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| 80 | |
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| 81 | /* |
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| 82 | * Setup for non-malloc allocation for small cases. |
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| 83 | */ |
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| 84 | |
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| 85 | #define FEWSTATES 20 /* must be less than UBITS */ |
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| 86 | #define FEWCOLORS 15 |
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| 87 | struct smalldfa { |
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| 88 | struct dfa dfa; |
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| 89 | struct sset ssets[FEWSTATES*2]; |
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| 90 | unsigned statesarea[FEWSTATES*2 + WORK]; |
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| 91 | struct sset *outsarea[FEWSTATES*2 * FEWCOLORS]; |
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| 92 | struct arcp incarea[FEWSTATES*2 * FEWCOLORS]; |
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| 93 | }; |
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| 94 | #define DOMALLOC ((struct smalldfa *)NULL) /* force malloc */ |
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| 95 | |
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| 96 | /* |
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| 97 | * Internal variables, bundled for easy passing around. |
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| 98 | */ |
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| 99 | |
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| 100 | struct vars { |
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| 101 | regex_t *re; |
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| 102 | struct guts *g; |
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| 103 | int eflags; /* copies of arguments */ |
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| 104 | size_t nmatch; |
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| 105 | regmatch_t *pmatch; |
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| 106 | rm_detail_t *details; |
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| 107 | chr *start; /* start of string */ |
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| 108 | chr *stop; /* just past end of string */ |
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| 109 | int err; /* error code if any (0 none) */ |
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| 110 | regoff_t *mem; /* memory vector for backtracking */ |
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| 111 | struct smalldfa dfa1; |
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| 112 | struct smalldfa dfa2; |
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| 113 | }; |
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| 114 | #define VISERR(vv) ((vv)->err != 0) /* have we seen an error yet? */ |
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| 115 | #define ISERR() VISERR(v) |
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| 116 | #define VERR(vv,e) (((vv)->err) ? (vv)->err : ((vv)->err = (e))) |
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| 117 | #define ERR(e) VERR(v, e) /* record an error */ |
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| 118 | #define NOERR() {if (ISERR()) return v->err;} /* if error seen, return it */ |
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| 119 | #define OFF(p) ((p) - v->start) |
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| 120 | #define LOFF(p) ((long)OFF(p)) |
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| 121 | |
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| 122 | /* |
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| 123 | * forward declarations |
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| 124 | */ |
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| 125 | /* =====^!^===== begin forwards =====^!^===== */ |
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| 126 | /* automatically gathered by fwd; do not hand-edit */ |
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| 127 | /* === regexec.c === */ |
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| 128 | int exec(regex_t *, CONST chr *, size_t, rm_detail_t *, size_t, regmatch_t [], int); |
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| 129 | static int find(struct vars *, struct cnfa *, struct colormap *); |
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| 130 | static int cfind(struct vars *, struct cnfa *, struct colormap *); |
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| 131 | static int cfindloop(struct vars *, struct cnfa *, struct colormap *, struct dfa *, struct dfa *, chr **); |
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| 132 | static VOID zapsubs(regmatch_t *, size_t); |
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| 133 | static VOID zapmem(struct vars *, struct subre *); |
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| 134 | static VOID subset(struct vars *, struct subre *, chr *, chr *); |
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| 135 | static int dissect(struct vars *, struct subre *, chr *, chr *); |
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| 136 | static int condissect(struct vars *, struct subre *, chr *, chr *); |
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| 137 | static int altdissect(struct vars *, struct subre *, chr *, chr *); |
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| 138 | static int cdissect(struct vars *, struct subre *, chr *, chr *); |
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| 139 | static int ccondissect(struct vars *, struct subre *, chr *, chr *); |
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| 140 | static int crevdissect(struct vars *, struct subre *, chr *, chr *); |
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| 141 | static int cbrdissect(struct vars *, struct subre *, chr *, chr *); |
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| 142 | static int caltdissect(struct vars *, struct subre *, chr *, chr *); |
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| 143 | /* === rege_dfa.c === */ |
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| 144 | static chr *longest(struct vars *, struct dfa *, chr *, chr *, int *); |
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| 145 | static chr *shortest(struct vars *, struct dfa *, chr *, chr *, chr *, chr **, int *); |
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| 146 | static chr *lastcold(struct vars *, struct dfa *); |
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| 147 | static struct dfa *newdfa(struct vars *, struct cnfa *, struct colormap *, struct smalldfa *); |
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| 148 | static VOID freedfa(struct dfa *); |
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| 149 | static unsigned hash(unsigned *, int); |
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| 150 | static struct sset *initialize(struct vars *, struct dfa *, chr *); |
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| 151 | static struct sset *miss(struct vars *, struct dfa *, struct sset *, pcolor, chr *, chr *); |
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| 152 | static int lacon(struct vars *, struct cnfa *, chr *, pcolor); |
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| 153 | static struct sset *getvacant(struct vars *, struct dfa *, chr *, chr *); |
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| 154 | static struct sset *pickss(struct vars *, struct dfa *, chr *, chr *); |
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| 155 | /* automatically gathered by fwd; do not hand-edit */ |
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| 156 | /* =====^!^===== end forwards =====^!^===== */ |
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| 157 | |
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| 158 | /* |
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| 159 | - exec - match regular expression |
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| 160 | ^ int exec(regex_t *, CONST chr *, size_t, rm_detail_t *, |
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| 161 | ^ size_t, regmatch_t [], int); |
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| 162 | */ |
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| 163 | int |
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| 164 | exec( |
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| 165 | regex_t *re, |
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| 166 | CONST chr *string, |
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| 167 | size_t len, |
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| 168 | rm_detail_t *details, |
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| 169 | size_t nmatch, |
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| 170 | regmatch_t pmatch[], |
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| 171 | int flags) |
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| 172 | { |
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| 173 | AllocVars(v); |
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| 174 | int st; |
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| 175 | size_t n; |
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| 176 | int backref; |
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| 177 | #define LOCALMAT 20 |
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| 178 | regmatch_t mat[LOCALMAT]; |
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| 179 | #define LOCALMEM 40 |
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| 180 | regoff_t mem[LOCALMEM]; |
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| 181 | |
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| 182 | /* |
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| 183 | * Sanity checks. |
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| 184 | */ |
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| 185 | |
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| 186 | if (re == NULL || string == NULL || re->re_magic != REMAGIC) { |
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| 187 | FreeVars(v); |
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| 188 | return REG_INVARG; |
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| 189 | } |
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| 190 | if (re->re_csize != sizeof(chr)) { |
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| 191 | FreeVars(v); |
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| 192 | return REG_MIXED; |
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| 193 | } |
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| 194 | |
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| 195 | /* |
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| 196 | * Setup. |
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| 197 | */ |
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| 198 | |
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| 199 | v->re = re; |
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| 200 | v->g = (struct guts *)re->re_guts; |
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| 201 | if ((v->g->cflags®_EXPECT) && details == NULL) { |
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| 202 | FreeVars(v); |
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| 203 | return REG_INVARG; |
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| 204 | } |
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| 205 | if (v->g->info®_UIMPOSSIBLE) { |
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| 206 | FreeVars(v); |
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| 207 | return REG_NOMATCH; |
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| 208 | } |
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| 209 | backref = (v->g->info®_UBACKREF) ? 1 : 0; |
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| 210 | v->eflags = flags; |
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| 211 | if (v->g->cflags®_NOSUB) { |
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| 212 | nmatch = 0; /* override client */ |
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| 213 | } |
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| 214 | v->nmatch = nmatch; |
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| 215 | if (backref) { |
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| 216 | /* |
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| 217 | * Need work area. |
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| 218 | */ |
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| 219 | |
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| 220 | if (v->g->nsub + 1 <= LOCALMAT) { |
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| 221 | v->pmatch = mat; |
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| 222 | } else { |
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| 223 | v->pmatch = (regmatch_t *) |
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| 224 | MALLOC((v->g->nsub + 1) * sizeof(regmatch_t)); |
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| 225 | } |
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| 226 | if (v->pmatch == NULL) { |
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| 227 | FreeVars(v); |
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| 228 | return REG_ESPACE; |
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| 229 | } |
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| 230 | v->nmatch = v->g->nsub + 1; |
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| 231 | } else { |
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| 232 | v->pmatch = pmatch; |
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| 233 | } |
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| 234 | v->details = details; |
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| 235 | v->start = (chr *)string; |
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| 236 | v->stop = (chr *)string + len; |
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| 237 | v->err = 0; |
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| 238 | if (backref) { |
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| 239 | /* |
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| 240 | * Need retry memory. |
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| 241 | */ |
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| 242 | |
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| 243 | assert(v->g->ntree >= 0); |
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| 244 | n = (size_t)v->g->ntree; |
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| 245 | if (n <= LOCALMEM) { |
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| 246 | v->mem = mem; |
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| 247 | } else { |
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| 248 | v->mem = (regoff_t *) MALLOC(n*sizeof(regoff_t)); |
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| 249 | } |
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| 250 | if (v->mem == NULL) { |
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| 251 | if (v->pmatch != pmatch && v->pmatch != mat) { |
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| 252 | FREE(v->pmatch); |
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| 253 | } |
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| 254 | FreeVars(v); |
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| 255 | return REG_ESPACE; |
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| 256 | } |
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| 257 | } else { |
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| 258 | v->mem = NULL; |
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| 259 | } |
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| 260 | |
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| 261 | /* |
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| 262 | * Do it. |
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| 263 | */ |
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| 264 | |
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| 265 | assert(v->g->tree != NULL); |
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| 266 | if (backref) { |
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| 267 | st = cfind(v, &v->g->tree->cnfa, &v->g->cmap); |
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| 268 | } else { |
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| 269 | st = find(v, &v->g->tree->cnfa, &v->g->cmap); |
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| 270 | } |
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| 271 | |
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| 272 | /* |
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| 273 | * Copy (portion of) match vector over if necessary. |
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| 274 | */ |
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| 275 | |
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| 276 | if (st == REG_OKAY && v->pmatch != pmatch && nmatch > 0) { |
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| 277 | zapsubs(pmatch, nmatch); |
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| 278 | n = (nmatch < v->nmatch) ? nmatch : v->nmatch; |
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| 279 | memcpy(VS(pmatch), VS(v->pmatch), n*sizeof(regmatch_t)); |
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| 280 | } |
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| 281 | |
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| 282 | /* |
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| 283 | * Clean up. |
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| 284 | */ |
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| 285 | |
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| 286 | if (v->pmatch != pmatch && v->pmatch != mat) { |
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| 287 | FREE(v->pmatch); |
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| 288 | } |
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| 289 | if (v->mem != NULL && v->mem != mem) { |
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| 290 | FREE(v->mem); |
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| 291 | } |
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| 292 | FreeVars(v); |
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| 293 | return st; |
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| 294 | } |
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| 295 | |
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| 296 | /* |
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| 297 | - find - find a match for the main NFA (no-complications case) |
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| 298 | ^ static int find(struct vars *, struct cnfa *, struct colormap *); |
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| 299 | */ |
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| 300 | static int |
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| 301 | find( |
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| 302 | struct vars *v, |
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| 303 | struct cnfa *cnfa, |
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| 304 | struct colormap *cm) |
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| 305 | { |
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| 306 | struct dfa *s; |
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| 307 | struct dfa *d; |
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| 308 | chr *begin; |
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| 309 | chr *end = NULL; |
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| 310 | chr *cold; |
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| 311 | chr *open; /* Open and close of range of possible |
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| 312 | * starts */ |
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| 313 | chr *close; |
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| 314 | int hitend; |
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| 315 | int shorter = (v->g->tree->flags&SHORTER) ? 1 : 0; |
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| 316 | |
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| 317 | /* |
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| 318 | * First, a shot with the search RE. |
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| 319 | */ |
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| 320 | |
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| 321 | s = newdfa(v, &v->g->search, cm, &v->dfa1); |
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| 322 | assert(!(ISERR() && s != NULL)); |
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| 323 | NOERR(); |
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| 324 | MDEBUG(("\nsearch at %ld\n", LOFF(v->start))); |
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| 325 | cold = NULL; |
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| 326 | close = shortest(v, s, v->start, v->start, v->stop, &cold, NULL); |
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| 327 | freedfa(s); |
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| 328 | NOERR(); |
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| 329 | if (v->g->cflags®_EXPECT) { |
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| 330 | assert(v->details != NULL); |
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| 331 | if (cold != NULL) { |
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| 332 | v->details->rm_extend.rm_so = OFF(cold); |
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| 333 | } else { |
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| 334 | v->details->rm_extend.rm_so = OFF(v->stop); |
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| 335 | } |
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| 336 | v->details->rm_extend.rm_eo = OFF(v->stop); /* unknown */ |
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| 337 | } |
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| 338 | if (close == NULL) { /* not found */ |
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| 339 | return REG_NOMATCH; |
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| 340 | } |
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| 341 | if (v->nmatch == 0) { /* found, don't need exact location */ |
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| 342 | return REG_OKAY; |
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| 343 | } |
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| 344 | |
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| 345 | /* |
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| 346 | * Find starting point and match. |
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| 347 | */ |
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| 348 | |
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| 349 | assert(cold != NULL); |
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| 350 | open = cold; |
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| 351 | cold = NULL; |
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| 352 | MDEBUG(("between %ld and %ld\n", LOFF(open), LOFF(close))); |
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| 353 | d = newdfa(v, cnfa, cm, &v->dfa1); |
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| 354 | assert(!(ISERR() && d != NULL)); |
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| 355 | NOERR(); |
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| 356 | for (begin = open; begin <= close; begin++) { |
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| 357 | MDEBUG(("\nfind trying at %ld\n", LOFF(begin))); |
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| 358 | if (shorter) { |
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| 359 | end = shortest(v, d, begin, begin, v->stop, NULL, &hitend); |
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| 360 | } else { |
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| 361 | end = longest(v, d, begin, v->stop, &hitend); |
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| 362 | } |
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| 363 | NOERR(); |
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| 364 | if (hitend && cold == NULL) { |
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| 365 | cold = begin; |
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| 366 | } |
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| 367 | if (end != NULL) { |
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| 368 | break; /* NOTE BREAK OUT */ |
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| 369 | } |
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| 370 | } |
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| 371 | assert(end != NULL); /* search RE succeeded so loop should */ |
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| 372 | freedfa(d); |
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| 373 | |
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| 374 | /* |
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| 375 | * And pin down details. |
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| 376 | */ |
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| 377 | |
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| 378 | assert(v->nmatch > 0); |
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| 379 | v->pmatch[0].rm_so = OFF(begin); |
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| 380 | v->pmatch[0].rm_eo = OFF(end); |
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| 381 | if (v->g->cflags®_EXPECT) { |
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| 382 | if (cold != NULL) { |
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| 383 | v->details->rm_extend.rm_so = OFF(cold); |
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| 384 | } else { |
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| 385 | v->details->rm_extend.rm_so = OFF(v->stop); |
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| 386 | } |
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| 387 | v->details->rm_extend.rm_eo = OFF(v->stop); /* unknown */ |
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| 388 | } |
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| 389 | if (v->nmatch == 1) { /* no need for submatches */ |
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| 390 | return REG_OKAY; |
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| 391 | } |
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| 392 | |
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| 393 | /* |
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| 394 | * Submatches. |
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| 395 | */ |
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| 396 | |
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| 397 | zapsubs(v->pmatch, v->nmatch); |
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| 398 | return dissect(v, v->g->tree, begin, end); |
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| 399 | } |
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| 400 | |
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| 401 | /* |
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| 402 | - cfind - find a match for the main NFA (with complications) |
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| 403 | ^ static int cfind(struct vars *, struct cnfa *, struct colormap *); |
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| 404 | */ |
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| 405 | static int |
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| 406 | cfind( |
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| 407 | struct vars *v, |
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| 408 | struct cnfa *cnfa, |
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| 409 | struct colormap *cm) |
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| 410 | { |
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| 411 | struct dfa *s; |
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| 412 | struct dfa *d; |
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| 413 | chr *cold = NULL; /* silence gcc 4 warning */ |
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| 414 | int ret; |
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| 415 | |
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| 416 | s = newdfa(v, &v->g->search, cm, &v->dfa1); |
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| 417 | NOERR(); |
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| 418 | d = newdfa(v, cnfa, cm, &v->dfa2); |
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| 419 | if (ISERR()) { |
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| 420 | assert(d == NULL); |
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| 421 | freedfa(s); |
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| 422 | return v->err; |
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| 423 | } |
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| 424 | |
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| 425 | ret = cfindloop(v, cnfa, cm, d, s, &cold); |
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| 426 | |
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| 427 | freedfa(d); |
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| 428 | freedfa(s); |
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| 429 | NOERR(); |
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| 430 | if (v->g->cflags®_EXPECT) { |
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| 431 | assert(v->details != NULL); |
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| 432 | if (cold != NULL) { |
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| 433 | v->details->rm_extend.rm_so = OFF(cold); |
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| 434 | } else { |
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| 435 | v->details->rm_extend.rm_so = OFF(v->stop); |
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| 436 | } |
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| 437 | v->details->rm_extend.rm_eo = OFF(v->stop); /* unknown */ |
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| 438 | } |
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| 439 | return ret; |
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| 440 | } |
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| 441 | |
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| 442 | /* |
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| 443 | - cfindloop - the heart of cfind |
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| 444 | ^ static int cfindloop(struct vars *, struct cnfa *, struct colormap *, |
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| 445 | ^ struct dfa *, struct dfa *, chr **); |
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| 446 | */ |
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| 447 | static int |
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| 448 | cfindloop( |
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| 449 | struct vars *v, |
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| 450 | struct cnfa *cnfa, |
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| 451 | struct colormap *cm, |
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| 452 | struct dfa *d, |
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| 453 | struct dfa *s, |
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| 454 | chr **coldp) /* where to put coldstart pointer */ |
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| 455 | { |
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| 456 | chr *begin; |
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| 457 | chr *end; |
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| 458 | chr *cold; |
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| 459 | chr *open; /* Open and close of range of possible |
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| 460 | * starts */ |
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| 461 | chr *close; |
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| 462 | chr *estart; |
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| 463 | chr *estop; |
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| 464 | int er; |
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| 465 | int shorter = v->g->tree->flags&SHORTER; |
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| 466 | int hitend; |
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| 467 | |
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| 468 | assert(d != NULL && s != NULL); |
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| 469 | cold = NULL; |
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| 470 | close = v->start; |
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| 471 | do { |
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| 472 | MDEBUG(("\ncsearch at %ld\n", LOFF(close))); |
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| 473 | close = shortest(v, s, close, close, v->stop, &cold, NULL); |
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| 474 | if (close == NULL) { |
---|
| 475 | break; /* NOTE BREAK */ |
---|
| 476 | } |
---|
| 477 | assert(cold != NULL); |
---|
| 478 | open = cold; |
---|
| 479 | cold = NULL; |
---|
| 480 | MDEBUG(("cbetween %ld and %ld\n", LOFF(open), LOFF(close))); |
---|
| 481 | for (begin = open; begin <= close; begin++) { |
---|
| 482 | MDEBUG(("\ncfind trying at %ld\n", LOFF(begin))); |
---|
| 483 | estart = begin; |
---|
| 484 | estop = v->stop; |
---|
| 485 | for (;;) { |
---|
| 486 | if (shorter) { |
---|
| 487 | end = shortest(v, d, begin, estart, estop, NULL, &hitend); |
---|
| 488 | } else { |
---|
| 489 | end = longest(v, d, begin, estop, &hitend); |
---|
| 490 | } |
---|
| 491 | if (hitend && cold == NULL) { |
---|
| 492 | cold = begin; |
---|
| 493 | } |
---|
| 494 | if (end == NULL) { |
---|
| 495 | break; /* NOTE BREAK OUT */ |
---|
| 496 | } |
---|
| 497 | |
---|
| 498 | MDEBUG(("tentative end %ld\n", LOFF(end))); |
---|
| 499 | zapsubs(v->pmatch, v->nmatch); |
---|
| 500 | zapmem(v, v->g->tree); |
---|
| 501 | er = cdissect(v, v->g->tree, begin, end); |
---|
| 502 | if (er == REG_OKAY) { |
---|
| 503 | if (v->nmatch > 0) { |
---|
| 504 | v->pmatch[0].rm_so = OFF(begin); |
---|
| 505 | v->pmatch[0].rm_eo = OFF(end); |
---|
| 506 | } |
---|
| 507 | *coldp = cold; |
---|
| 508 | return REG_OKAY; |
---|
| 509 | } |
---|
| 510 | if (er != REG_NOMATCH) { |
---|
| 511 | ERR(er); |
---|
| 512 | return er; |
---|
| 513 | } |
---|
| 514 | if ((shorter) ? end == estop : end == begin) { |
---|
| 515 | /* |
---|
| 516 | * No point in trying again. |
---|
| 517 | */ |
---|
| 518 | |
---|
| 519 | *coldp = cold; |
---|
| 520 | return REG_NOMATCH; |
---|
| 521 | } |
---|
| 522 | |
---|
| 523 | /* |
---|
| 524 | * Go around and try again |
---|
| 525 | */ |
---|
| 526 | |
---|
| 527 | if (shorter) { |
---|
| 528 | estart = end + 1; |
---|
| 529 | } else { |
---|
| 530 | estop = end - 1; |
---|
| 531 | } |
---|
| 532 | } |
---|
| 533 | } |
---|
| 534 | } while (close < v->stop); |
---|
| 535 | |
---|
| 536 | *coldp = cold; |
---|
| 537 | return REG_NOMATCH; |
---|
| 538 | } |
---|
| 539 | |
---|
| 540 | /* |
---|
| 541 | - zapsubs - initialize the subexpression matches to "no match" |
---|
| 542 | ^ static VOID zapsubs(regmatch_t *, size_t); |
---|
| 543 | */ |
---|
| 544 | static void |
---|
| 545 | zapsubs( |
---|
| 546 | regmatch_t *p, |
---|
| 547 | size_t n) |
---|
| 548 | { |
---|
| 549 | size_t i; |
---|
| 550 | |
---|
| 551 | for (i = n-1; i > 0; i--) { |
---|
| 552 | p[i].rm_so = -1; |
---|
| 553 | p[i].rm_eo = -1; |
---|
| 554 | } |
---|
| 555 | } |
---|
| 556 | |
---|
| 557 | /* |
---|
| 558 | - zapmem - initialize the retry memory of a subtree to zeros |
---|
| 559 | ^ static VOID zapmem(struct vars *, struct subre *); |
---|
| 560 | */ |
---|
| 561 | static void |
---|
| 562 | zapmem( |
---|
| 563 | struct vars *v, |
---|
| 564 | struct subre *t) |
---|
| 565 | { |
---|
| 566 | if (t == NULL) { |
---|
| 567 | return; |
---|
| 568 | } |
---|
| 569 | |
---|
| 570 | assert(v->mem != NULL); |
---|
| 571 | v->mem[t->retry] = 0; |
---|
| 572 | if (t->op == '(') { |
---|
| 573 | assert(t->subno > 0); |
---|
| 574 | v->pmatch[t->subno].rm_so = -1; |
---|
| 575 | v->pmatch[t->subno].rm_eo = -1; |
---|
| 576 | } |
---|
| 577 | |
---|
| 578 | if (t->left != NULL) { |
---|
| 579 | zapmem(v, t->left); |
---|
| 580 | } |
---|
| 581 | if (t->right != NULL) { |
---|
| 582 | zapmem(v, t->right); |
---|
| 583 | } |
---|
| 584 | } |
---|
| 585 | |
---|
| 586 | /* |
---|
| 587 | - subset - set any subexpression relevant to a successful subre |
---|
| 588 | ^ static VOID subset(struct vars *, struct subre *, chr *, chr *); |
---|
| 589 | */ |
---|
| 590 | static void |
---|
| 591 | subset( |
---|
| 592 | struct vars *v, |
---|
| 593 | struct subre *sub, |
---|
| 594 | chr *begin, |
---|
| 595 | chr *end) |
---|
| 596 | { |
---|
| 597 | int n = sub->subno; |
---|
| 598 | |
---|
| 599 | assert(n > 0); |
---|
| 600 | if ((size_t)n >= v->nmatch) { |
---|
| 601 | return; |
---|
| 602 | } |
---|
| 603 | |
---|
| 604 | MDEBUG(("setting %d\n", n)); |
---|
| 605 | v->pmatch[n].rm_so = OFF(begin); |
---|
| 606 | v->pmatch[n].rm_eo = OFF(end); |
---|
| 607 | } |
---|
| 608 | |
---|
| 609 | /* |
---|
| 610 | - dissect - determine subexpression matches (uncomplicated case) |
---|
| 611 | ^ static int dissect(struct vars *, struct subre *, chr *, chr *); |
---|
| 612 | */ |
---|
| 613 | static int /* regexec return code */ |
---|
| 614 | dissect( |
---|
| 615 | struct vars *v, |
---|
| 616 | struct subre *t, |
---|
| 617 | chr *begin, /* beginning of relevant substring */ |
---|
| 618 | chr *end) /* end of same */ |
---|
| 619 | { |
---|
| 620 | assert(t != NULL); |
---|
| 621 | MDEBUG(("dissect %ld-%ld\n", LOFF(begin), LOFF(end))); |
---|
| 622 | |
---|
| 623 | switch (t->op) { |
---|
| 624 | case '=': /* terminal node */ |
---|
| 625 | assert(t->left == NULL && t->right == NULL); |
---|
| 626 | return REG_OKAY; /* no action, parent did the work */ |
---|
| 627 | break; |
---|
| 628 | case '|': /* alternation */ |
---|
| 629 | assert(t->left != NULL); |
---|
| 630 | return altdissect(v, t, begin, end); |
---|
| 631 | break; |
---|
| 632 | case 'b': /* back ref -- shouldn't be calling us! */ |
---|
| 633 | return REG_ASSERT; |
---|
| 634 | break; |
---|
| 635 | case '.': /* concatenation */ |
---|
| 636 | assert(t->left != NULL && t->right != NULL); |
---|
| 637 | return condissect(v, t, begin, end); |
---|
| 638 | break; |
---|
| 639 | case '(': /* capturing */ |
---|
| 640 | assert(t->left != NULL && t->right == NULL); |
---|
| 641 | assert(t->subno > 0); |
---|
| 642 | subset(v, t, begin, end); |
---|
| 643 | return dissect(v, t->left, begin, end); |
---|
| 644 | break; |
---|
| 645 | default: |
---|
| 646 | return REG_ASSERT; |
---|
| 647 | break; |
---|
| 648 | } |
---|
| 649 | } |
---|
| 650 | |
---|
| 651 | /* |
---|
| 652 | - condissect - determine concatenation subexpression matches (uncomplicated) |
---|
| 653 | ^ static int condissect(struct vars *, struct subre *, chr *, chr *); |
---|
| 654 | */ |
---|
| 655 | static int /* regexec return code */ |
---|
| 656 | condissect( |
---|
| 657 | struct vars *v, |
---|
| 658 | struct subre *t, |
---|
| 659 | chr *begin, /* beginning of relevant substring */ |
---|
| 660 | chr *end) /* end of same */ |
---|
| 661 | { |
---|
| 662 | struct dfa *d; |
---|
| 663 | struct dfa *d2; |
---|
| 664 | chr *mid; |
---|
| 665 | int i; |
---|
| 666 | int shorter = (t->left->flags&SHORTER) ? 1 : 0; |
---|
| 667 | chr *stop = (shorter) ? end : begin; |
---|
| 668 | |
---|
| 669 | assert(t->op == '.'); |
---|
| 670 | assert(t->left != NULL && t->left->cnfa.nstates > 0); |
---|
| 671 | assert(t->right != NULL && t->right->cnfa.nstates > 0); |
---|
| 672 | |
---|
| 673 | d = newdfa(v, &t->left->cnfa, &v->g->cmap, &v->dfa1); |
---|
| 674 | NOERR(); |
---|
| 675 | d2 = newdfa(v, &t->right->cnfa, &v->g->cmap, &v->dfa2); |
---|
| 676 | if (ISERR()) { |
---|
| 677 | assert(d2 == NULL); |
---|
| 678 | freedfa(d); |
---|
| 679 | return v->err; |
---|
| 680 | } |
---|
| 681 | |
---|
| 682 | /* |
---|
| 683 | * Pick a tentative midpoint. |
---|
| 684 | */ |
---|
| 685 | |
---|
| 686 | if (shorter) { |
---|
| 687 | mid = shortest(v, d, begin, begin, end, NULL, NULL); |
---|
| 688 | } else { |
---|
| 689 | mid = longest(v, d, begin, end, NULL); |
---|
| 690 | } |
---|
| 691 | if (mid == NULL) { |
---|
| 692 | freedfa(d); |
---|
| 693 | freedfa(d2); |
---|
| 694 | return REG_ASSERT; |
---|
| 695 | } |
---|
| 696 | MDEBUG(("tentative midpoint %ld\n", LOFF(mid))); |
---|
| 697 | |
---|
| 698 | /* |
---|
| 699 | * Iterate until satisfaction or failure. |
---|
| 700 | */ |
---|
| 701 | |
---|
| 702 | while (longest(v, d2, mid, end, NULL) != end) { |
---|
| 703 | /* |
---|
| 704 | * That midpoint didn't work, find a new one. |
---|
| 705 | */ |
---|
| 706 | |
---|
| 707 | if (mid == stop) { |
---|
| 708 | /* |
---|
| 709 | * All possibilities exhausted! |
---|
| 710 | */ |
---|
| 711 | |
---|
| 712 | MDEBUG(("no midpoint!\n")); |
---|
| 713 | freedfa(d); |
---|
| 714 | freedfa(d2); |
---|
| 715 | return REG_ASSERT; |
---|
| 716 | } |
---|
| 717 | if (shorter) { |
---|
| 718 | mid = shortest(v, d, begin, mid+1, end, NULL, NULL); |
---|
| 719 | } else { |
---|
| 720 | mid = longest(v, d, begin, mid-1, NULL); |
---|
| 721 | } |
---|
| 722 | if (mid == NULL) { |
---|
| 723 | /* |
---|
| 724 | * Failed to find a new one! |
---|
| 725 | */ |
---|
| 726 | |
---|
| 727 | MDEBUG(("failed midpoint!\n")); |
---|
| 728 | freedfa(d); |
---|
| 729 | freedfa(d2); |
---|
| 730 | return REG_ASSERT; |
---|
| 731 | } |
---|
| 732 | MDEBUG(("new midpoint %ld\n", LOFF(mid))); |
---|
| 733 | } |
---|
| 734 | |
---|
| 735 | /* |
---|
| 736 | * Satisfaction. |
---|
| 737 | */ |
---|
| 738 | |
---|
| 739 | MDEBUG(("successful\n")); |
---|
| 740 | freedfa(d); |
---|
| 741 | freedfa(d2); |
---|
| 742 | i = dissect(v, t->left, begin, mid); |
---|
| 743 | if (i != REG_OKAY) { |
---|
| 744 | return i; |
---|
| 745 | } |
---|
| 746 | return dissect(v, t->right, mid, end); |
---|
| 747 | } |
---|
| 748 | |
---|
| 749 | /* |
---|
| 750 | - altdissect - determine alternative subexpression matches (uncomplicated) |
---|
| 751 | ^ static int altdissect(struct vars *, struct subre *, chr *, chr *); |
---|
| 752 | */ |
---|
| 753 | static int /* regexec return code */ |
---|
| 754 | altdissect( |
---|
| 755 | struct vars *v, |
---|
| 756 | struct subre *t, |
---|
| 757 | chr *begin, /* beginning of relevant substring */ |
---|
| 758 | chr *end) /* end of same */ |
---|
| 759 | { |
---|
| 760 | struct dfa *d; |
---|
| 761 | int i; |
---|
| 762 | |
---|
| 763 | assert(t != NULL); |
---|
| 764 | assert(t->op == '|'); |
---|
| 765 | |
---|
| 766 | for (i = 0; t != NULL; t = t->right, i++) { |
---|
| 767 | MDEBUG(("trying %dth\n", i)); |
---|
| 768 | assert(t->left != NULL && t->left->cnfa.nstates > 0); |
---|
| 769 | d = newdfa(v, &t->left->cnfa, &v->g->cmap, &v->dfa1); |
---|
| 770 | if (ISERR()) { |
---|
| 771 | return v->err; |
---|
| 772 | } |
---|
| 773 | if (longest(v, d, begin, end, NULL) == end) { |
---|
| 774 | MDEBUG(("success\n")); |
---|
| 775 | freedfa(d); |
---|
| 776 | return dissect(v, t->left, begin, end); |
---|
| 777 | } |
---|
| 778 | freedfa(d); |
---|
| 779 | } |
---|
| 780 | return REG_ASSERT; /* none of them matched?!? */ |
---|
| 781 | } |
---|
| 782 | |
---|
| 783 | /* |
---|
| 784 | - cdissect - determine subexpression matches (with complications) |
---|
| 785 | * The retry memory stores the offset of the trial midpoint from begin, plus 1 |
---|
| 786 | * so that 0 uniquely means "clean slate". |
---|
| 787 | ^ static int cdissect(struct vars *, struct subre *, chr *, chr *); |
---|
| 788 | */ |
---|
| 789 | static int /* regexec return code */ |
---|
| 790 | cdissect( |
---|
| 791 | struct vars *v, |
---|
| 792 | struct subre *t, |
---|
| 793 | chr *begin, /* beginning of relevant substring */ |
---|
| 794 | chr *end) /* end of same */ |
---|
| 795 | { |
---|
| 796 | int er; |
---|
| 797 | |
---|
| 798 | assert(t != NULL); |
---|
| 799 | MDEBUG(("cdissect %ld-%ld %c\n", LOFF(begin), LOFF(end), t->op)); |
---|
| 800 | |
---|
| 801 | switch (t->op) { |
---|
| 802 | case '=': /* terminal node */ |
---|
| 803 | assert(t->left == NULL && t->right == NULL); |
---|
| 804 | return REG_OKAY; /* no action, parent did the work */ |
---|
| 805 | break; |
---|
| 806 | case '|': /* alternation */ |
---|
| 807 | assert(t->left != NULL); |
---|
| 808 | return caltdissect(v, t, begin, end); |
---|
| 809 | break; |
---|
| 810 | case 'b': /* back ref -- shouldn't be calling us! */ |
---|
| 811 | assert(t->left == NULL && t->right == NULL); |
---|
| 812 | return cbrdissect(v, t, begin, end); |
---|
| 813 | break; |
---|
| 814 | case '.': /* concatenation */ |
---|
| 815 | assert(t->left != NULL && t->right != NULL); |
---|
| 816 | return ccondissect(v, t, begin, end); |
---|
| 817 | break; |
---|
| 818 | case '(': /* capturing */ |
---|
| 819 | assert(t->left != NULL && t->right == NULL); |
---|
| 820 | assert(t->subno > 0); |
---|
| 821 | er = cdissect(v, t->left, begin, end); |
---|
| 822 | if (er == REG_OKAY) { |
---|
| 823 | subset(v, t, begin, end); |
---|
| 824 | } |
---|
| 825 | return er; |
---|
| 826 | break; |
---|
| 827 | default: |
---|
| 828 | return REG_ASSERT; |
---|
| 829 | break; |
---|
| 830 | } |
---|
| 831 | } |
---|
| 832 | |
---|
| 833 | /* |
---|
| 834 | - ccondissect - concatenation subexpression matches (with complications) |
---|
| 835 | * The retry memory stores the offset of the trial midpoint from begin, plus 1 |
---|
| 836 | * so that 0 uniquely means "clean slate". |
---|
| 837 | ^ static int ccondissect(struct vars *, struct subre *, chr *, chr *); |
---|
| 838 | */ |
---|
| 839 | static int /* regexec return code */ |
---|
| 840 | ccondissect( |
---|
| 841 | struct vars *v, |
---|
| 842 | struct subre *t, |
---|
| 843 | chr *begin, /* beginning of relevant substring */ |
---|
| 844 | chr *end) /* end of same */ |
---|
| 845 | { |
---|
| 846 | struct dfa *d; |
---|
| 847 | struct dfa *d2; |
---|
| 848 | chr *mid; |
---|
| 849 | int er; |
---|
| 850 | |
---|
| 851 | assert(t->op == '.'); |
---|
| 852 | assert(t->left != NULL && t->left->cnfa.nstates > 0); |
---|
| 853 | assert(t->right != NULL && t->right->cnfa.nstates > 0); |
---|
| 854 | |
---|
| 855 | if (t->left->flags&SHORTER) { /* reverse scan */ |
---|
| 856 | return crevdissect(v, t, begin, end); |
---|
| 857 | } |
---|
| 858 | |
---|
| 859 | d = newdfa(v, &t->left->cnfa, &v->g->cmap, DOMALLOC); |
---|
| 860 | if (ISERR()) { |
---|
| 861 | return v->err; |
---|
| 862 | } |
---|
| 863 | d2 = newdfa(v, &t->right->cnfa, &v->g->cmap, DOMALLOC); |
---|
| 864 | if (ISERR()) { |
---|
| 865 | freedfa(d); |
---|
| 866 | return v->err; |
---|
| 867 | } |
---|
| 868 | MDEBUG(("cconcat %d\n", t->retry)); |
---|
| 869 | |
---|
| 870 | /* |
---|
| 871 | * Pick a tentative midpoint. |
---|
| 872 | */ |
---|
| 873 | |
---|
| 874 | if (v->mem[t->retry] == 0) { |
---|
| 875 | mid = longest(v, d, begin, end, NULL); |
---|
| 876 | if (mid == NULL) { |
---|
| 877 | freedfa(d); |
---|
| 878 | freedfa(d2); |
---|
| 879 | return REG_NOMATCH; |
---|
| 880 | } |
---|
| 881 | MDEBUG(("tentative midpoint %ld\n", LOFF(mid))); |
---|
| 882 | v->mem[t->retry] = (mid - begin) + 1; |
---|
| 883 | } else { |
---|
| 884 | mid = begin + (v->mem[t->retry] - 1); |
---|
| 885 | MDEBUG(("working midpoint %ld\n", LOFF(mid))); |
---|
| 886 | } |
---|
| 887 | |
---|
| 888 | /* |
---|
| 889 | * Iterate until satisfaction or failure. |
---|
| 890 | */ |
---|
| 891 | |
---|
| 892 | for (;;) { |
---|
| 893 | /* |
---|
| 894 | * Try this midpoint on for size. |
---|
| 895 | */ |
---|
| 896 | |
---|
| 897 | er = cdissect(v, t->left, begin, mid); |
---|
| 898 | if ((er == REG_OKAY) && (longest(v, d2, mid, end, NULL) == end) |
---|
| 899 | && (er = cdissect(v, t->right, mid, end)) == REG_OKAY) { |
---|
| 900 | break; /* NOTE BREAK OUT */ |
---|
| 901 | } |
---|
| 902 | if ((er != REG_OKAY) && (er != REG_NOMATCH)) { |
---|
| 903 | freedfa(d); |
---|
| 904 | freedfa(d2); |
---|
| 905 | return er; |
---|
| 906 | } |
---|
| 907 | |
---|
| 908 | /* |
---|
| 909 | * That midpoint didn't work, find a new one. |
---|
| 910 | */ |
---|
| 911 | |
---|
| 912 | if (mid == begin) { |
---|
| 913 | /* |
---|
| 914 | * All possibilities exhausted. |
---|
| 915 | */ |
---|
| 916 | |
---|
| 917 | MDEBUG(("%d no midpoint\n", t->retry)); |
---|
| 918 | freedfa(d); |
---|
| 919 | freedfa(d2); |
---|
| 920 | return REG_NOMATCH; |
---|
| 921 | } |
---|
| 922 | mid = longest(v, d, begin, mid-1, NULL); |
---|
| 923 | if (mid == NULL) { |
---|
| 924 | /* |
---|
| 925 | * Failed to find a new one. |
---|
| 926 | */ |
---|
| 927 | |
---|
| 928 | MDEBUG(("%d failed midpoint\n", t->retry)); |
---|
| 929 | freedfa(d); |
---|
| 930 | freedfa(d2); |
---|
| 931 | return REG_NOMATCH; |
---|
| 932 | } |
---|
| 933 | MDEBUG(("%d: new midpoint %ld\n", t->retry, LOFF(mid))); |
---|
| 934 | v->mem[t->retry] = (mid - begin) + 1; |
---|
| 935 | zapmem(v, t->left); |
---|
| 936 | zapmem(v, t->right); |
---|
| 937 | } |
---|
| 938 | |
---|
| 939 | /* |
---|
| 940 | * Satisfaction. |
---|
| 941 | */ |
---|
| 942 | |
---|
| 943 | MDEBUG(("successful\n")); |
---|
| 944 | freedfa(d); |
---|
| 945 | freedfa(d2); |
---|
| 946 | return REG_OKAY; |
---|
| 947 | } |
---|
| 948 | |
---|
| 949 | /* |
---|
| 950 | - crevdissect - determine backref shortest-first subexpression matches |
---|
| 951 | * The retry memory stores the offset of the trial midpoint from begin, plus 1 |
---|
| 952 | * so that 0 uniquely means "clean slate". |
---|
| 953 | ^ static int crevdissect(struct vars *, struct subre *, chr *, chr *); |
---|
| 954 | */ |
---|
| 955 | static int /* regexec return code */ |
---|
| 956 | crevdissect( |
---|
| 957 | struct vars *v, |
---|
| 958 | struct subre *t, |
---|
| 959 | chr *begin, /* beginning of relevant substring */ |
---|
| 960 | chr *end) /* end of same */ |
---|
| 961 | { |
---|
| 962 | struct dfa *d; |
---|
| 963 | struct dfa *d2; |
---|
| 964 | chr *mid; |
---|
| 965 | int er; |
---|
| 966 | |
---|
| 967 | assert(t->op == '.'); |
---|
| 968 | assert(t->left != NULL && t->left->cnfa.nstates > 0); |
---|
| 969 | assert(t->right != NULL && t->right->cnfa.nstates > 0); |
---|
| 970 | assert(t->left->flags&SHORTER); |
---|
| 971 | |
---|
| 972 | /* |
---|
| 973 | * Concatenation -- need to split the substring between parts. |
---|
| 974 | */ |
---|
| 975 | |
---|
| 976 | d = newdfa(v, &t->left->cnfa, &v->g->cmap, DOMALLOC); |
---|
| 977 | if (ISERR()) { |
---|
| 978 | return v->err; |
---|
| 979 | } |
---|
| 980 | d2 = newdfa(v, &t->right->cnfa, &v->g->cmap, DOMALLOC); |
---|
| 981 | if (ISERR()) { |
---|
| 982 | freedfa(d); |
---|
| 983 | return v->err; |
---|
| 984 | } |
---|
| 985 | MDEBUG(("crev %d\n", t->retry)); |
---|
| 986 | |
---|
| 987 | /* |
---|
| 988 | * Pick a tentative midpoint. |
---|
| 989 | */ |
---|
| 990 | |
---|
| 991 | if (v->mem[t->retry] == 0) { |
---|
| 992 | mid = shortest(v, d, begin, begin, end, NULL, NULL); |
---|
| 993 | if (mid == NULL) { |
---|
| 994 | freedfa(d); |
---|
| 995 | freedfa(d2); |
---|
| 996 | return REG_NOMATCH; |
---|
| 997 | } |
---|
| 998 | MDEBUG(("tentative midpoint %ld\n", LOFF(mid))); |
---|
| 999 | v->mem[t->retry] = (mid - begin) + 1; |
---|
| 1000 | } else { |
---|
| 1001 | mid = begin + (v->mem[t->retry] - 1); |
---|
| 1002 | MDEBUG(("working midpoint %ld\n", LOFF(mid))); |
---|
| 1003 | } |
---|
| 1004 | |
---|
| 1005 | /* |
---|
| 1006 | * Iterate until satisfaction or failure. |
---|
| 1007 | */ |
---|
| 1008 | |
---|
| 1009 | for (;;) { |
---|
| 1010 | /* |
---|
| 1011 | * Try this midpoint on for size. |
---|
| 1012 | */ |
---|
| 1013 | |
---|
| 1014 | er = cdissect(v, t->left, begin, mid); |
---|
| 1015 | if ((er == REG_OKAY) && (longest(v, d2, mid, end, NULL) == end) |
---|
| 1016 | && (er = cdissect(v, t->right, mid, end)) == REG_OKAY) { |
---|
| 1017 | break; /* NOTE BREAK OUT */ |
---|
| 1018 | } |
---|
| 1019 | if (er != REG_OKAY && er != REG_NOMATCH) { |
---|
| 1020 | freedfa(d); |
---|
| 1021 | freedfa(d2); |
---|
| 1022 | return er; |
---|
| 1023 | } |
---|
| 1024 | |
---|
| 1025 | /* |
---|
| 1026 | * That midpoint didn't work, find a new one. |
---|
| 1027 | */ |
---|
| 1028 | |
---|
| 1029 | if (mid == end) { |
---|
| 1030 | /* |
---|
| 1031 | * All possibilities exhausted. |
---|
| 1032 | */ |
---|
| 1033 | |
---|
| 1034 | MDEBUG(("%d no midpoint\n", t->retry)); |
---|
| 1035 | freedfa(d); |
---|
| 1036 | freedfa(d2); |
---|
| 1037 | return REG_NOMATCH; |
---|
| 1038 | } |
---|
| 1039 | mid = shortest(v, d, begin, mid+1, end, NULL, NULL); |
---|
| 1040 | if (mid == NULL) { |
---|
| 1041 | /* |
---|
| 1042 | * Failed to find a new one. |
---|
| 1043 | */ |
---|
| 1044 | |
---|
| 1045 | MDEBUG(("%d failed midpoint\n", t->retry)); |
---|
| 1046 | freedfa(d); |
---|
| 1047 | freedfa(d2); |
---|
| 1048 | return REG_NOMATCH; |
---|
| 1049 | } |
---|
| 1050 | MDEBUG(("%d: new midpoint %ld\n", t->retry, LOFF(mid))); |
---|
| 1051 | v->mem[t->retry] = (mid - begin) + 1; |
---|
| 1052 | zapmem(v, t->left); |
---|
| 1053 | zapmem(v, t->right); |
---|
| 1054 | } |
---|
| 1055 | |
---|
| 1056 | /* |
---|
| 1057 | * Satisfaction. |
---|
| 1058 | */ |
---|
| 1059 | |
---|
| 1060 | MDEBUG(("successful\n")); |
---|
| 1061 | freedfa(d); |
---|
| 1062 | freedfa(d2); |
---|
| 1063 | return REG_OKAY; |
---|
| 1064 | } |
---|
| 1065 | |
---|
| 1066 | /* |
---|
| 1067 | - cbrdissect - determine backref subexpression matches |
---|
| 1068 | ^ static int cbrdissect(struct vars *, struct subre *, chr *, chr *); |
---|
| 1069 | */ |
---|
| 1070 | static int /* regexec return code */ |
---|
| 1071 | cbrdissect( |
---|
| 1072 | struct vars *v, |
---|
| 1073 | struct subre *t, |
---|
| 1074 | chr *begin, /* beginning of relevant substring */ |
---|
| 1075 | chr *end) /* end of same */ |
---|
| 1076 | { |
---|
| 1077 | int i; |
---|
| 1078 | int n = t->subno; |
---|
| 1079 | size_t len; |
---|
| 1080 | chr *paren; |
---|
| 1081 | chr *p; |
---|
| 1082 | chr *stop; |
---|
| 1083 | int min = t->min; |
---|
| 1084 | int max = t->max; |
---|
| 1085 | |
---|
| 1086 | assert(t != NULL); |
---|
| 1087 | assert(t->op == 'b'); |
---|
| 1088 | assert(n >= 0); |
---|
| 1089 | assert((size_t)n < v->nmatch); |
---|
| 1090 | |
---|
| 1091 | MDEBUG(("cbackref n%d %d{%d-%d}\n", t->retry, n, min, max)); |
---|
| 1092 | |
---|
| 1093 | if (v->pmatch[n].rm_so == -1) { |
---|
| 1094 | return REG_NOMATCH; |
---|
| 1095 | } |
---|
| 1096 | paren = v->start + v->pmatch[n].rm_so; |
---|
| 1097 | len = v->pmatch[n].rm_eo - v->pmatch[n].rm_so; |
---|
| 1098 | |
---|
| 1099 | /* |
---|
| 1100 | * No room to maneuver -- retries are pointless. |
---|
| 1101 | */ |
---|
| 1102 | |
---|
| 1103 | if (v->mem[t->retry]) { |
---|
| 1104 | return REG_NOMATCH; |
---|
| 1105 | } |
---|
| 1106 | v->mem[t->retry] = 1; |
---|
| 1107 | |
---|
| 1108 | /* |
---|
| 1109 | * Special-case zero-length string. |
---|
| 1110 | */ |
---|
| 1111 | |
---|
| 1112 | if (len == 0) { |
---|
| 1113 | if (begin == end) { |
---|
| 1114 | return REG_OKAY; |
---|
| 1115 | } |
---|
| 1116 | return REG_NOMATCH; |
---|
| 1117 | } |
---|
| 1118 | |
---|
| 1119 | /* |
---|
| 1120 | * And too-short string. |
---|
| 1121 | */ |
---|
| 1122 | |
---|
| 1123 | assert(end >= begin); |
---|
| 1124 | if ((size_t)(end - begin) < len) { |
---|
| 1125 | return REG_NOMATCH; |
---|
| 1126 | } |
---|
| 1127 | stop = end - len; |
---|
| 1128 | |
---|
| 1129 | /* |
---|
| 1130 | * Count occurrences. |
---|
| 1131 | */ |
---|
| 1132 | |
---|
| 1133 | i = 0; |
---|
| 1134 | for (p = begin; p <= stop && (i < max || max == INFINITY); p += len) { |
---|
| 1135 | if ((*v->g->compare)(paren, p, len) != 0) { |
---|
| 1136 | break; |
---|
| 1137 | } |
---|
| 1138 | i++; |
---|
| 1139 | } |
---|
| 1140 | MDEBUG(("cbackref found %d\n", i)); |
---|
| 1141 | |
---|
| 1142 | /* |
---|
| 1143 | * And sort it out. |
---|
| 1144 | */ |
---|
| 1145 | |
---|
| 1146 | if (p != end) { /* didn't consume all of it */ |
---|
| 1147 | return REG_NOMATCH; |
---|
| 1148 | } |
---|
| 1149 | if (min <= i && (i <= max || max == INFINITY)) { |
---|
| 1150 | return REG_OKAY; |
---|
| 1151 | } |
---|
| 1152 | return REG_NOMATCH; /* out of range */ |
---|
| 1153 | } |
---|
| 1154 | |
---|
| 1155 | /* |
---|
| 1156 | - caltdissect - determine alternative subexpression matches (w. complications) |
---|
| 1157 | ^ static int caltdissect(struct vars *, struct subre *, chr *, chr *); |
---|
| 1158 | */ |
---|
| 1159 | static int /* regexec return code */ |
---|
| 1160 | caltdissect( |
---|
| 1161 | struct vars *v, |
---|
| 1162 | struct subre *t, |
---|
| 1163 | chr *begin, /* beginning of relevant substring */ |
---|
| 1164 | chr *end) /* end of same */ |
---|
| 1165 | { |
---|
| 1166 | struct dfa *d; |
---|
| 1167 | int er; |
---|
| 1168 | #define UNTRIED 0 /* not yet tried at all */ |
---|
| 1169 | #define TRYING 1 /* top matched, trying submatches */ |
---|
| 1170 | #define TRIED 2 /* top didn't match or submatches exhausted */ |
---|
| 1171 | |
---|
| 1172 | if (t == NULL) { |
---|
| 1173 | return REG_NOMATCH; |
---|
| 1174 | } |
---|
| 1175 | assert(t->op == '|'); |
---|
| 1176 | if (v->mem[t->retry] == TRIED) { |
---|
| 1177 | return caltdissect(v, t->right, begin, end); |
---|
| 1178 | } |
---|
| 1179 | |
---|
| 1180 | MDEBUG(("calt n%d\n", t->retry)); |
---|
| 1181 | assert(t->left != NULL); |
---|
| 1182 | |
---|
| 1183 | if (v->mem[t->retry] == UNTRIED) { |
---|
| 1184 | d = newdfa(v, &t->left->cnfa, &v->g->cmap, DOMALLOC); |
---|
| 1185 | if (ISERR()) { |
---|
| 1186 | return v->err; |
---|
| 1187 | } |
---|
| 1188 | if (longest(v, d, begin, end, NULL) != end) { |
---|
| 1189 | freedfa(d); |
---|
| 1190 | v->mem[t->retry] = TRIED; |
---|
| 1191 | return caltdissect(v, t->right, begin, end); |
---|
| 1192 | } |
---|
| 1193 | freedfa(d); |
---|
| 1194 | MDEBUG(("calt matched\n")); |
---|
| 1195 | v->mem[t->retry] = TRYING; |
---|
| 1196 | } |
---|
| 1197 | |
---|
| 1198 | er = cdissect(v, t->left, begin, end); |
---|
| 1199 | if (er != REG_NOMATCH) { |
---|
| 1200 | return er; |
---|
| 1201 | } |
---|
| 1202 | |
---|
| 1203 | v->mem[t->retry] = TRIED; |
---|
| 1204 | return caltdissect(v, t->right, begin, end); |
---|
| 1205 | } |
---|
| 1206 | |
---|
| 1207 | #include "rege_dfa.c" |
---|
| 1208 | |
---|
| 1209 | /* |
---|
| 1210 | * Local Variables: |
---|
| 1211 | * mode: c |
---|
| 1212 | * c-basic-offset: 4 |
---|
| 1213 | * fill-column: 78 |
---|
| 1214 | * End: |
---|
| 1215 | */ |
---|