[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 | * @(#)regcomp.c 8.5 (Berkeley) 3/20/94 |
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| 34 | */ |
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| 35 | |
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| 36 | #ifndef _NO_REGEX |
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| 37 | |
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| 38 | #if defined(LIBC_SCCS) && !defined(lint) |
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| 39 | static char sccsid[] = "@(#)regcomp.c 8.5 (Berkeley) 3/20/94"; |
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| 40 | #endif /* LIBC_SCCS and not lint */ |
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| 41 | #include <sys/cdefs.h> |
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| 42 | |
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| 43 | #include <sys/types.h> |
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| 44 | #include <stdio.h> |
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| 45 | #include <string.h> |
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| 46 | #include <ctype.h> |
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| 47 | #include <limits.h> |
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| 48 | #include <stdlib.h> |
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| 49 | #include <regex.h> |
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| 50 | |
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| 51 | #include "collate.h" |
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| 52 | |
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| 53 | #include "utils.h" |
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| 54 | #include "regex2.h" |
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| 55 | |
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| 56 | #include "cclass.h" |
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| 57 | #include "cname.h" |
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| 58 | |
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| 59 | /* |
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| 60 | * parse structure, passed up and down to avoid global variables and |
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| 61 | * other clumsinesses |
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| 62 | */ |
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| 63 | struct parse { |
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| 64 | char *next; /* next character in RE */ |
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| 65 | char *end; /* end of string (-> NUL normally) */ |
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| 66 | int error; /* has an error been seen? */ |
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| 67 | sop *strip; /* malloced strip */ |
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| 68 | sopno ssize; /* malloced strip size (allocated) */ |
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| 69 | sopno slen; /* malloced strip length (used) */ |
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| 70 | int ncsalloc; /* number of csets allocated */ |
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| 71 | struct re_guts *g; |
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| 72 | # define NPAREN 10 /* we need to remember () 1-9 for back refs */ |
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| 73 | sopno pbegin[NPAREN]; /* -> ( ([0] unused) */ |
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| 74 | sopno pend[NPAREN]; /* -> ) ([0] unused) */ |
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| 75 | }; |
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| 76 | |
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| 77 | /* ========= begin header generated by ./mkh ========= */ |
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| 78 | #ifdef __cplusplus |
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| 79 | extern "C" { |
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| 80 | #endif |
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| 81 | |
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| 82 | /* === regcomp.c === */ |
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| 83 | static void p_ere(struct parse *p, int stop); |
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| 84 | static void p_ere_exp(struct parse *p); |
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| 85 | static void p_str(struct parse *p); |
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| 86 | static void p_bre(struct parse *p, int end1, int end2); |
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| 87 | static int p_simp_re(struct parse *p, int starordinary); |
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| 88 | static int p_count(struct parse *p); |
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| 89 | static void p_bracket(struct parse *p); |
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| 90 | static void p_b_term(struct parse *p, cset *cs); |
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| 91 | static void p_b_cclass(struct parse *p, cset *cs); |
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| 92 | static void p_b_eclass(struct parse *p, cset *cs); |
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| 93 | static char p_b_symbol(struct parse *p); |
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| 94 | static char p_b_coll_elem(struct parse *p, int endc); |
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| 95 | static char othercase(int ch); |
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| 96 | static void bothcases(struct parse *p, int ch); |
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| 97 | static void ordinary(struct parse *p, int ch); |
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| 98 | static void nonnewline(struct parse *p); |
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| 99 | static void repeat(struct parse *p, sopno start, int from, int to); |
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| 100 | static int seterr(struct parse *p, int e); |
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| 101 | static cset *allocset(struct parse *p); |
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| 102 | static void freeset(struct parse *p, cset *cs); |
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| 103 | static int freezeset(struct parse *p, cset *cs); |
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| 104 | static int firstch(struct parse *p, cset *cs); |
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| 105 | static int nch(struct parse *p, cset *cs); |
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| 106 | #if used |
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| 107 | static void mcadd(struct parse *p, cset *cs, char *cp); |
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| 108 | static void mcsub(cset *cs, char *cp); |
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| 109 | static int mcin(cset *cs, char *cp); |
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| 110 | static char *mcfind(cset *cs, char *cp); |
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| 111 | #endif |
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| 112 | static void mcinvert(struct parse *p, cset *cs); |
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| 113 | static void mccase(struct parse *p, cset *cs); |
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| 114 | static int isinsets(struct re_guts *g, int c); |
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| 115 | static int samesets(struct re_guts *g, int c1, int c2); |
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| 116 | static void categorize(struct parse *p, struct re_guts *g); |
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| 117 | static sopno dupl(struct parse *p, sopno start, sopno finish); |
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| 118 | static void doemit(struct parse *p, sop op, size_t opnd); |
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| 119 | static void doinsert(struct parse *p, sop op, size_t opnd, sopno pos); |
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| 120 | static void dofwd(struct parse *p, sopno pos, sop value); |
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| 121 | static void enlarge(struct parse *p, sopno size); |
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| 122 | static void stripsnug(struct parse *p, struct re_guts *g); |
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| 123 | static void findmust(struct parse *p, struct re_guts *g); |
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| 124 | static int altoffset(sop *scan, int offset, int mccs); |
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| 125 | static void computejumps(struct parse *p, struct re_guts *g); |
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| 126 | static void computematchjumps(struct parse *p, struct re_guts *g); |
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| 127 | static sopno pluscount(struct parse *p, struct re_guts *g); |
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| 128 | |
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| 129 | #ifdef __cplusplus |
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| 130 | } |
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| 131 | #endif |
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| 132 | /* ========= end header generated by ./mkh ========= */ |
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| 133 | |
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| 134 | static char nuls[10]; /* place to point scanner in event of error */ |
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| 135 | |
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| 136 | /* |
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| 137 | * macros for use with parse structure |
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| 138 | * BEWARE: these know that the parse structure is named `p' !!! |
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| 139 | */ |
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| 140 | #define PEEK() (*p->next) |
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| 141 | #define PEEK2() (*(p->next+1)) |
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| 142 | #define MORE() (p->next < p->end) |
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| 143 | #define MORE2() (p->next+1 < p->end) |
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| 144 | #define SEE(c) (MORE() && PEEK() == (c)) |
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| 145 | #define SEETWO(a, b) (MORE() && MORE2() && PEEK() == (a) && PEEK2() == (b)) |
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| 146 | #define EAT(c) ((SEE(c)) ? (NEXT(), 1) : 0) |
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| 147 | #define EATTWO(a, b) ((SEETWO(a, b)) ? (NEXT2(), 1) : 0) |
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| 148 | #define NEXT() (p->next++) |
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| 149 | #define NEXT2() (p->next += 2) |
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| 150 | #define NEXTn(n) (p->next += (n)) |
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| 151 | #define GETNEXT() (*p->next++) |
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| 152 | #define SETERROR(e) seterr(p, (e)) |
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| 153 | #define REQUIRE(co, e) ((co) || SETERROR(e)) |
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| 154 | #define MUSTSEE(c, e) (REQUIRE(MORE() && PEEK() == (c), e)) |
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| 155 | #define MUSTEAT(c, e) (REQUIRE(MORE() && GETNEXT() == (c), e)) |
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| 156 | #define MUSTNOTSEE(c, e) (REQUIRE(!MORE() || PEEK() != (c), e)) |
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| 157 | #define EMIT(op, sopnd) doemit(p, (sop)(op), (size_t)(sopnd)) |
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| 158 | #define INSERT(op, pos) doinsert(p, (sop)(op), HERE()-(pos)+1, pos) |
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| 159 | #define AHEAD(pos) dofwd(p, pos, HERE()-(pos)) |
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| 160 | #define ASTERN(sop, pos) EMIT(sop, HERE()-pos) |
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| 161 | #define HERE() (p->slen) |
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| 162 | #define THERE() (p->slen - 1) |
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| 163 | #define THERETHERE() (p->slen - 2) |
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| 164 | #define DROP(n) (p->slen -= (n)) |
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| 165 | |
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| 166 | #ifndef NDEBUG |
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| 167 | static int never = 0; /* for use in asserts; shuts lint up */ |
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| 168 | #else |
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| 169 | #define never 0 /* some <assert.h>s have bugs too */ |
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| 170 | #endif |
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| 171 | |
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| 172 | /* Macro used by computejump()/computematchjump() */ |
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| 173 | #define MIN(a,b) ((a)<(b)?(a):(b)) |
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| 174 | |
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| 175 | /* |
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| 176 | - regcomp - interface for parser and compilation |
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| 177 | = extern int regcomp(regex_t *__restrict, const char *__restrict, int); |
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| 178 | = #define REG_BASIC 0000 |
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| 179 | = #define REG_EXTENDED 0001 |
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| 180 | = #define REG_ICASE 0002 |
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| 181 | = #define REG_NOSUB 0004 |
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| 182 | = #define REG_NEWLINE 0010 |
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| 183 | = #define REG_NOSPEC 0020 |
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| 184 | = #define REG_PEND 0040 |
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| 185 | = #define REG_DUMP 0200 |
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| 186 | */ |
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| 187 | int /* 0 success, otherwise REG_something */ |
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| 188 | regcomp(preg, pattern, cflags) |
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| 189 | regex_t *__restrict preg; |
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| 190 | const char *__restrict pattern; |
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| 191 | int cflags; |
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| 192 | { |
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| 193 | struct parse pa; |
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| 194 | struct re_guts *g; |
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| 195 | struct parse *p = &pa; |
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| 196 | int i; |
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| 197 | size_t len; |
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| 198 | #ifdef REDEBUG |
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| 199 | # define GOODFLAGS(f) (f) |
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| 200 | #else |
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| 201 | # define GOODFLAGS(f) ((f)&~REG_DUMP) |
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| 202 | #endif |
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| 203 | |
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| 204 | cflags = GOODFLAGS(cflags); |
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| 205 | if ((cflags®_EXTENDED) && (cflags®_NOSPEC)) |
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| 206 | return(REG_INVARG); |
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| 207 | |
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| 208 | if (cflags®_PEND) { |
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| 209 | if (preg->re_endp < pattern) |
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| 210 | return(REG_INVARG); |
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| 211 | len = preg->re_endp - pattern; |
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| 212 | } else |
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| 213 | len = strlen((char *)pattern); |
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| 214 | |
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| 215 | /* do the mallocs early so failure handling is easy */ |
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| 216 | g = (struct re_guts *)malloc(sizeof(struct re_guts) + |
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| 217 | (NC-1)*sizeof(cat_t)); |
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| 218 | if (g == NULL) |
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| 219 | return(REG_ESPACE); |
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| 220 | p->ssize = len/(size_t)2*(size_t)3 + (size_t)1; /* ugh */ |
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| 221 | p->strip = (sop *)malloc(p->ssize * sizeof(sop)); |
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| 222 | p->slen = 0; |
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| 223 | if (p->strip == NULL) { |
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| 224 | free((char *)g); |
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| 225 | return(REG_ESPACE); |
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| 226 | } |
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| 227 | |
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| 228 | /* set things up */ |
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| 229 | p->g = g; |
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| 230 | p->next = (char *)pattern; /* convenience; we do not modify it */ |
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| 231 | p->end = p->next + len; |
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| 232 | p->error = 0; |
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| 233 | p->ncsalloc = 0; |
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| 234 | for (i = 0; i < NPAREN; i++) { |
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| 235 | p->pbegin[i] = 0; |
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| 236 | p->pend[i] = 0; |
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| 237 | } |
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| 238 | g->csetsize = NC; |
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| 239 | g->sets = NULL; |
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| 240 | g->setbits = NULL; |
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| 241 | g->ncsets = 0; |
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| 242 | g->cflags = cflags; |
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| 243 | g->iflags = 0; |
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| 244 | g->nbol = 0; |
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| 245 | g->neol = 0; |
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| 246 | g->must = NULL; |
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| 247 | g->moffset = -1; |
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| 248 | g->charjump = NULL; |
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| 249 | g->matchjump = NULL; |
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| 250 | g->mlen = 0; |
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| 251 | g->nsub = 0; |
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| 252 | g->ncategories = 1; /* category 0 is "everything else" */ |
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| 253 | g->categories = &g->catspace[-(CHAR_MIN)]; |
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| 254 | (void) memset((char *)g->catspace, 0, NC*sizeof(cat_t)); |
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| 255 | g->backrefs = 0; |
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| 256 | |
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| 257 | /* do it */ |
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| 258 | EMIT(OEND, 0); |
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| 259 | g->firststate = THERE(); |
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| 260 | if (cflags®_EXTENDED) |
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| 261 | p_ere(p, OUT); |
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| 262 | else if (cflags®_NOSPEC) |
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| 263 | p_str(p); |
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| 264 | else |
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| 265 | p_bre(p, OUT, OUT); |
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| 266 | EMIT(OEND, 0); |
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| 267 | g->laststate = THERE(); |
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| 268 | |
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| 269 | /* tidy up loose ends and fill things in */ |
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| 270 | categorize(p, g); |
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| 271 | stripsnug(p, g); |
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| 272 | findmust(p, g); |
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| 273 | /* only use Boyer-Moore algorithm if the pattern is bigger |
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| 274 | * than three characters |
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| 275 | */ |
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| 276 | if(g->mlen > 3) { |
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| 277 | computejumps(p, g); |
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| 278 | computematchjumps(p, g); |
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| 279 | if(g->matchjump == NULL && g->charjump != NULL) { |
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| 280 | free(g->charjump); |
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| 281 | g->charjump = NULL; |
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| 282 | } |
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| 283 | } |
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| 284 | g->nplus = pluscount(p, g); |
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| 285 | g->magic = MAGIC2; |
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| 286 | preg->re_nsub = g->nsub; |
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| 287 | preg->re_g = g; |
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| 288 | preg->re_magic = MAGIC1; |
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| 289 | #ifndef REDEBUG |
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| 290 | /* not debugging, so can't rely on the assert() in regexec() */ |
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| 291 | if (g->iflags&BAD) |
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| 292 | SETERROR(REG_ASSERT); |
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| 293 | #endif |
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| 294 | |
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| 295 | /* win or lose, we're done */ |
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| 296 | if (p->error != 0) /* lose */ |
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| 297 | regfree(preg); |
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| 298 | return(p->error); |
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| 299 | } |
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| 300 | |
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| 301 | /* |
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| 302 | - p_ere - ERE parser top level, concatenation and alternation |
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| 303 | == static void p_ere(struct parse *p, int stop); |
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| 304 | */ |
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| 305 | static void |
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| 306 | p_ere(p, stop) |
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| 307 | struct parse *p; |
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| 308 | int stop; /* character this ERE should end at */ |
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| 309 | { |
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| 310 | char c; |
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| 311 | sopno prevback = 0; |
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| 312 | sopno prevfwd = 0; |
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| 313 | sopno conc; |
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| 314 | int first = 1; /* is this the first alternative? */ |
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| 315 | |
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| 316 | for (;;) { |
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| 317 | /* do a bunch of concatenated expressions */ |
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| 318 | conc = HERE(); |
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| 319 | while (MORE() && (c = PEEK()) != '|' && c != stop) |
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| 320 | p_ere_exp(p); |
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| 321 | (void)REQUIRE(HERE() != conc, REG_EMPTY); /* require nonempty */ |
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| 322 | |
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| 323 | if (!EAT('|')) |
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| 324 | break; /* NOTE BREAK OUT */ |
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| 325 | |
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| 326 | if (first) { |
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| 327 | INSERT(OCH_, conc); /* offset is wrong */ |
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| 328 | prevfwd = conc; |
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| 329 | prevback = conc; |
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| 330 | first = 0; |
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| 331 | } |
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| 332 | ASTERN(OOR1, prevback); |
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| 333 | prevback = THERE(); |
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| 334 | AHEAD(prevfwd); /* fix previous offset */ |
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| 335 | prevfwd = HERE(); |
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| 336 | EMIT(OOR2, 0); /* offset is very wrong */ |
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| 337 | } |
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| 338 | |
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| 339 | if (!first) { /* tail-end fixups */ |
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| 340 | AHEAD(prevfwd); |
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| 341 | ASTERN(O_CH, prevback); |
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| 342 | } |
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| 343 | |
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| 344 | assert(!MORE() || SEE(stop)); |
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| 345 | } |
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| 346 | |
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| 347 | /* |
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| 348 | - p_ere_exp - parse one subERE, an atom possibly followed by a repetition op |
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| 349 | == static void p_ere_exp(struct parse *p); |
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| 350 | */ |
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| 351 | static void |
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| 352 | p_ere_exp(p) |
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| 353 | struct parse *p; |
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| 354 | { |
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| 355 | char c; |
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| 356 | sopno pos; |
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| 357 | int count; |
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| 358 | int count2; |
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| 359 | sopno subno; |
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| 360 | int wascaret = 0; |
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| 361 | |
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| 362 | assert(MORE()); /* caller should have ensured this */ |
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| 363 | c = GETNEXT(); |
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| 364 | |
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| 365 | pos = HERE(); |
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| 366 | switch (c) { |
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| 367 | case '(': |
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| 368 | (void)REQUIRE(MORE(), REG_EPAREN); |
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| 369 | p->g->nsub++; |
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| 370 | subno = p->g->nsub; |
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| 371 | if (subno < NPAREN) |
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| 372 | p->pbegin[subno] = HERE(); |
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| 373 | EMIT(OLPAREN, subno); |
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| 374 | if (!SEE(')')) |
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| 375 | p_ere(p, ')'); |
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| 376 | if (subno < NPAREN) { |
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| 377 | p->pend[subno] = HERE(); |
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| 378 | assert(p->pend[subno] != 0); |
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| 379 | } |
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| 380 | EMIT(ORPAREN, subno); |
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| 381 | (void)MUSTEAT(')', REG_EPAREN); |
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| 382 | break; |
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| 383 | #ifndef POSIX_MISTAKE |
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| 384 | case ')': /* happens only if no current unmatched ( */ |
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| 385 | /* |
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| 386 | * You may ask, why the ifndef? Because I didn't notice |
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| 387 | * this until slightly too late for 1003.2, and none of the |
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| 388 | * other 1003.2 regular-expression reviewers noticed it at |
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| 389 | * all. So an unmatched ) is legal POSIX, at least until |
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| 390 | * we can get it fixed. |
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| 391 | */ |
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| 392 | SETERROR(REG_EPAREN); |
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| 393 | break; |
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| 394 | #endif |
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| 395 | case '^': |
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| 396 | EMIT(OBOL, 0); |
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| 397 | p->g->iflags |= USEBOL; |
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| 398 | p->g->nbol++; |
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| 399 | wascaret = 1; |
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| 400 | break; |
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| 401 | case '$': |
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| 402 | EMIT(OEOL, 0); |
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| 403 | p->g->iflags |= USEEOL; |
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| 404 | p->g->neol++; |
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| 405 | break; |
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| 406 | case '|': |
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| 407 | SETERROR(REG_EMPTY); |
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| 408 | break; |
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| 409 | case '*': |
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| 410 | case '+': |
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| 411 | case '?': |
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| 412 | SETERROR(REG_BADRPT); |
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| 413 | break; |
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| 414 | case '.': |
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| 415 | if (p->g->cflags®_NEWLINE) |
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| 416 | nonnewline(p); |
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| 417 | else |
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| 418 | EMIT(OANY, 0); |
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| 419 | break; |
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| 420 | case '[': |
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| 421 | p_bracket(p); |
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| 422 | break; |
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| 423 | case '\\': |
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| 424 | (void)REQUIRE(MORE(), REG_EESCAPE); |
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| 425 | c = GETNEXT(); |
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| 426 | ordinary(p, c); |
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| 427 | break; |
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| 428 | case '{': /* okay as ordinary except if digit follows */ |
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| 429 | (void)REQUIRE(!MORE() || !isdigit((uch)PEEK()), REG_BADRPT); |
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| 430 | /* FALLTHROUGH */ |
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| 431 | default: |
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| 432 | ordinary(p, c); |
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| 433 | break; |
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| 434 | } |
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| 435 | |
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| 436 | if (!MORE()) |
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| 437 | return; |
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| 438 | c = PEEK(); |
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| 439 | /* we call { a repetition if followed by a digit */ |
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| 440 | if (!( c == '*' || c == '+' || c == '?' || |
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| 441 | (c == '{' && MORE2() && isdigit((uch)PEEK2())) )) |
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| 442 | return; /* no repetition, we're done */ |
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| 443 | NEXT(); |
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| 444 | |
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| 445 | (void)REQUIRE(!wascaret, REG_BADRPT); |
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| 446 | switch (c) { |
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| 447 | case '*': /* implemented as +? */ |
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| 448 | /* this case does not require the (y|) trick, noKLUDGE */ |
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| 449 | INSERT(OPLUS_, pos); |
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| 450 | ASTERN(O_PLUS, pos); |
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| 451 | INSERT(OQUEST_, pos); |
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| 452 | ASTERN(O_QUEST, pos); |
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| 453 | break; |
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| 454 | case '+': |
---|
| 455 | INSERT(OPLUS_, pos); |
---|
| 456 | ASTERN(O_PLUS, pos); |
---|
| 457 | break; |
---|
| 458 | case '?': |
---|
| 459 | /* KLUDGE: emit y? as (y|) until subtle bug gets fixed */ |
---|
| 460 | INSERT(OCH_, pos); /* offset slightly wrong */ |
---|
| 461 | ASTERN(OOR1, pos); /* this one's right */ |
---|
| 462 | AHEAD(pos); /* fix the OCH_ */ |
---|
| 463 | EMIT(OOR2, 0); /* offset very wrong... */ |
---|
| 464 | AHEAD(THERE()); /* ...so fix it */ |
---|
| 465 | ASTERN(O_CH, THERETHERE()); |
---|
| 466 | break; |
---|
| 467 | case '{': |
---|
| 468 | count = p_count(p); |
---|
| 469 | if (EAT(',')) { |
---|
| 470 | if (isdigit((uch)PEEK())) { |
---|
| 471 | count2 = p_count(p); |
---|
| 472 | (void)REQUIRE(count <= count2, REG_BADBR); |
---|
| 473 | } else /* single number with comma */ |
---|
| 474 | count2 = INFINITY; |
---|
| 475 | } else /* just a single number */ |
---|
| 476 | count2 = count; |
---|
| 477 | repeat(p, pos, count, count2); |
---|
| 478 | if (!EAT('}')) { /* error heuristics */ |
---|
| 479 | while (MORE() && PEEK() != '}') |
---|
| 480 | NEXT(); |
---|
| 481 | (void)REQUIRE(MORE(), REG_EBRACE); |
---|
| 482 | SETERROR(REG_BADBR); |
---|
| 483 | } |
---|
| 484 | break; |
---|
| 485 | } |
---|
| 486 | |
---|
| 487 | if (!MORE()) |
---|
| 488 | return; |
---|
| 489 | c = PEEK(); |
---|
| 490 | if (!( c == '*' || c == '+' || c == '?' || |
---|
| 491 | (c == '{' && MORE2() && isdigit((uch)PEEK2())) ) ) |
---|
| 492 | return; |
---|
| 493 | SETERROR(REG_BADRPT); |
---|
| 494 | } |
---|
| 495 | |
---|
| 496 | /* |
---|
| 497 | - p_str - string (no metacharacters) "parser" |
---|
| 498 | == static void p_str(struct parse *p); |
---|
| 499 | */ |
---|
| 500 | static void |
---|
| 501 | p_str(p) |
---|
| 502 | struct parse *p; |
---|
| 503 | { |
---|
| 504 | (void)REQUIRE(MORE(), REG_EMPTY); |
---|
| 505 | while (MORE()) |
---|
| 506 | ordinary(p, GETNEXT()); |
---|
| 507 | } |
---|
| 508 | |
---|
| 509 | /* |
---|
| 510 | - p_bre - BRE parser top level, anchoring and concatenation |
---|
| 511 | == static void p_bre(struct parse *p, int end1, \ |
---|
| 512 | == int end2); |
---|
| 513 | * Giving end1 as OUT essentially eliminates the end1/end2 check. |
---|
| 514 | * |
---|
| 515 | * This implementation is a bit of a kludge, in that a trailing $ is first |
---|
| 516 | * taken as an ordinary character and then revised to be an anchor. The |
---|
| 517 | * only undesirable side effect is that '$' gets included as a character |
---|
| 518 | * category in such cases. This is fairly harmless; not worth fixing. |
---|
| 519 | * The amount of lookahead needed to avoid this kludge is excessive. |
---|
| 520 | */ |
---|
| 521 | static void |
---|
| 522 | p_bre(p, end1, end2) |
---|
| 523 | struct parse *p; |
---|
| 524 | int end1; /* first terminating character */ |
---|
| 525 | int end2; /* second terminating character */ |
---|
| 526 | { |
---|
| 527 | sopno start = HERE(); |
---|
| 528 | int first = 1; /* first subexpression? */ |
---|
| 529 | int wasdollar = 0; |
---|
| 530 | |
---|
| 531 | if (EAT('^')) { |
---|
| 532 | EMIT(OBOL, 0); |
---|
| 533 | p->g->iflags |= USEBOL; |
---|
| 534 | p->g->nbol++; |
---|
| 535 | } |
---|
| 536 | while (MORE() && !SEETWO(end1, end2)) { |
---|
| 537 | wasdollar = p_simp_re(p, first); |
---|
| 538 | first = 0; |
---|
| 539 | } |
---|
| 540 | if (wasdollar) { /* oops, that was a trailing anchor */ |
---|
| 541 | DROP(1); |
---|
| 542 | EMIT(OEOL, 0); |
---|
| 543 | p->g->iflags |= USEEOL; |
---|
| 544 | p->g->neol++; |
---|
| 545 | } |
---|
| 546 | |
---|
| 547 | (void)REQUIRE(HERE() != start, REG_EMPTY); /* require nonempty */ |
---|
| 548 | } |
---|
| 549 | |
---|
| 550 | /* |
---|
| 551 | - p_simp_re - parse a simple RE, an atom possibly followed by a repetition |
---|
| 552 | == static int p_simp_re(struct parse *p, int starordinary); |
---|
| 553 | */ |
---|
| 554 | static int /* was the simple RE an unbackslashed $? */ |
---|
| 555 | p_simp_re(p, starordinary) |
---|
| 556 | struct parse *p; |
---|
| 557 | int starordinary; /* is a leading * an ordinary character? */ |
---|
| 558 | { |
---|
| 559 | int c; |
---|
| 560 | int count; |
---|
| 561 | int count2; |
---|
| 562 | sopno pos; |
---|
| 563 | int i; |
---|
| 564 | sopno subno; |
---|
| 565 | # define BACKSL (1<<CHAR_BIT) |
---|
| 566 | |
---|
| 567 | pos = HERE(); /* repetion op, if any, covers from here */ |
---|
| 568 | |
---|
| 569 | assert(MORE()); /* caller should have ensured this */ |
---|
| 570 | c = GETNEXT(); |
---|
| 571 | if (c == '\\') { |
---|
| 572 | (void)REQUIRE(MORE(), REG_EESCAPE); |
---|
| 573 | c = BACKSL | GETNEXT(); |
---|
| 574 | } |
---|
| 575 | switch (c) { |
---|
| 576 | case '.': |
---|
| 577 | if (p->g->cflags®_NEWLINE) |
---|
| 578 | nonnewline(p); |
---|
| 579 | else |
---|
| 580 | EMIT(OANY, 0); |
---|
| 581 | break; |
---|
| 582 | case '[': |
---|
| 583 | p_bracket(p); |
---|
| 584 | break; |
---|
| 585 | case BACKSL|'{': |
---|
| 586 | SETERROR(REG_BADRPT); |
---|
| 587 | break; |
---|
| 588 | case BACKSL|'(': |
---|
| 589 | p->g->nsub++; |
---|
| 590 | subno = p->g->nsub; |
---|
| 591 | if (subno < NPAREN) |
---|
| 592 | p->pbegin[subno] = HERE(); |
---|
| 593 | EMIT(OLPAREN, subno); |
---|
| 594 | /* the MORE here is an error heuristic */ |
---|
| 595 | if (MORE() && !SEETWO('\\', ')')) |
---|
| 596 | p_bre(p, '\\', ')'); |
---|
| 597 | if (subno < NPAREN) { |
---|
| 598 | p->pend[subno] = HERE(); |
---|
| 599 | assert(p->pend[subno] != 0); |
---|
| 600 | } |
---|
| 601 | EMIT(ORPAREN, subno); |
---|
| 602 | (void)REQUIRE(EATTWO('\\', ')'), REG_EPAREN); |
---|
| 603 | break; |
---|
| 604 | case BACKSL|')': /* should not get here -- must be user */ |
---|
| 605 | case BACKSL|'}': |
---|
| 606 | SETERROR(REG_EPAREN); |
---|
| 607 | break; |
---|
| 608 | case BACKSL|'1': |
---|
| 609 | case BACKSL|'2': |
---|
| 610 | case BACKSL|'3': |
---|
| 611 | case BACKSL|'4': |
---|
| 612 | case BACKSL|'5': |
---|
| 613 | case BACKSL|'6': |
---|
| 614 | case BACKSL|'7': |
---|
| 615 | case BACKSL|'8': |
---|
| 616 | case BACKSL|'9': |
---|
| 617 | i = (c&~BACKSL) - '0'; |
---|
| 618 | assert(i < NPAREN); |
---|
| 619 | if (p->pend[i] != 0) { |
---|
| 620 | assert(i <= p->g->nsub); |
---|
| 621 | EMIT(OBACK_, i); |
---|
| 622 | assert(p->pbegin[i] != 0); |
---|
| 623 | assert(OP(p->strip[p->pbegin[i]]) == OLPAREN); |
---|
| 624 | assert(OP(p->strip[p->pend[i]]) == ORPAREN); |
---|
| 625 | (void) dupl(p, p->pbegin[i]+1, p->pend[i]); |
---|
| 626 | EMIT(O_BACK, i); |
---|
| 627 | } else |
---|
| 628 | SETERROR(REG_ESUBREG); |
---|
| 629 | p->g->backrefs = 1; |
---|
| 630 | break; |
---|
| 631 | case '*': |
---|
| 632 | (void)REQUIRE(starordinary, REG_BADRPT); |
---|
| 633 | /* FALLTHROUGH */ |
---|
| 634 | default: |
---|
| 635 | ordinary(p, (char)c); |
---|
| 636 | break; |
---|
| 637 | } |
---|
| 638 | |
---|
| 639 | if (EAT('*')) { /* implemented as +? */ |
---|
| 640 | /* this case does not require the (y|) trick, noKLUDGE */ |
---|
| 641 | INSERT(OPLUS_, pos); |
---|
| 642 | ASTERN(O_PLUS, pos); |
---|
| 643 | INSERT(OQUEST_, pos); |
---|
| 644 | ASTERN(O_QUEST, pos); |
---|
| 645 | } else if (EATTWO('\\', '{')) { |
---|
| 646 | count = p_count(p); |
---|
| 647 | if (EAT(',')) { |
---|
| 648 | if (MORE() && isdigit((uch)PEEK())) { |
---|
| 649 | count2 = p_count(p); |
---|
| 650 | (void)REQUIRE(count <= count2, REG_BADBR); |
---|
| 651 | } else /* single number with comma */ |
---|
| 652 | count2 = INFINITY; |
---|
| 653 | } else /* just a single number */ |
---|
| 654 | count2 = count; |
---|
| 655 | repeat(p, pos, count, count2); |
---|
| 656 | if (!EATTWO('\\', '}')) { /* error heuristics */ |
---|
| 657 | while (MORE() && !SEETWO('\\', '}')) |
---|
| 658 | NEXT(); |
---|
| 659 | (void)REQUIRE(MORE(), REG_EBRACE); |
---|
| 660 | SETERROR(REG_BADBR); |
---|
| 661 | } |
---|
| 662 | } else if (c == '$') /* $ (but not \$) ends it */ |
---|
| 663 | return(1); |
---|
| 664 | |
---|
| 665 | return(0); |
---|
| 666 | } |
---|
| 667 | |
---|
| 668 | /* |
---|
| 669 | - p_count - parse a repetition count |
---|
| 670 | == static int p_count(struct parse *p); |
---|
| 671 | */ |
---|
| 672 | static int /* the value */ |
---|
| 673 | p_count(p) |
---|
| 674 | struct parse *p; |
---|
| 675 | { |
---|
| 676 | int count = 0; |
---|
| 677 | int ndigits = 0; |
---|
| 678 | |
---|
| 679 | while (MORE() && isdigit((uch)PEEK()) && count <= DUPMAX) { |
---|
| 680 | count = count*10 + (GETNEXT() - '0'); |
---|
| 681 | ndigits++; |
---|
| 682 | } |
---|
| 683 | |
---|
| 684 | (void)REQUIRE(ndigits > 0 && count <= DUPMAX, REG_BADBR); |
---|
| 685 | return(count); |
---|
| 686 | } |
---|
| 687 | |
---|
| 688 | /* |
---|
| 689 | - p_bracket - parse a bracketed character list |
---|
| 690 | == static void p_bracket(struct parse *p); |
---|
| 691 | * |
---|
| 692 | * Note a significant property of this code: if the allocset() did SETERROR, |
---|
| 693 | * no set operations are done. |
---|
| 694 | */ |
---|
| 695 | static void |
---|
| 696 | p_bracket(p) |
---|
| 697 | struct parse *p; |
---|
| 698 | { |
---|
| 699 | cset *cs = allocset(p); |
---|
| 700 | int invert = 0; |
---|
| 701 | |
---|
| 702 | /* Dept of Truly Sickening Special-Case Kludges */ |
---|
| 703 | if (p->next + 5 < p->end && strncmp(p->next, "[:<:]]", 6) == 0) { |
---|
| 704 | EMIT(OBOW, 0); |
---|
| 705 | NEXTn(6); |
---|
| 706 | return; |
---|
| 707 | } |
---|
| 708 | if (p->next + 5 < p->end && strncmp(p->next, "[:>:]]", 6) == 0) { |
---|
| 709 | EMIT(OEOW, 0); |
---|
| 710 | NEXTn(6); |
---|
| 711 | return; |
---|
| 712 | } |
---|
| 713 | |
---|
| 714 | if (EAT('^')) |
---|
| 715 | invert++; /* make note to invert set at end */ |
---|
| 716 | if (EAT(']')) |
---|
| 717 | CHadd(cs, ']'); |
---|
| 718 | else if (EAT('-')) |
---|
| 719 | CHadd(cs, '-'); |
---|
| 720 | while (MORE() && PEEK() != ']' && !SEETWO('-', ']')) |
---|
| 721 | p_b_term(p, cs); |
---|
| 722 | if (EAT('-')) |
---|
| 723 | CHadd(cs, '-'); |
---|
| 724 | (void)MUSTEAT(']', REG_EBRACK); |
---|
| 725 | |
---|
| 726 | if (p->error != 0) /* don't mess things up further */ |
---|
| 727 | return; |
---|
| 728 | |
---|
| 729 | if (p->g->cflags®_ICASE) { |
---|
| 730 | int i; |
---|
| 731 | int ci; |
---|
| 732 | |
---|
| 733 | for (i = p->g->csetsize - 1; i >= 0; i--) |
---|
| 734 | if (CHIN(cs, i) && isalpha(i)) { |
---|
| 735 | ci = othercase(i); |
---|
| 736 | if (ci != i) |
---|
| 737 | CHadd(cs, ci); |
---|
| 738 | } |
---|
| 739 | if (cs->multis != NULL) |
---|
| 740 | mccase(p, cs); |
---|
| 741 | } |
---|
| 742 | if (invert) { |
---|
| 743 | int i; |
---|
| 744 | |
---|
| 745 | for (i = p->g->csetsize - 1; i >= 0; i--) |
---|
| 746 | if (CHIN(cs, i)) |
---|
| 747 | CHsub(cs, i); |
---|
| 748 | else |
---|
| 749 | CHadd(cs, i); |
---|
| 750 | if (p->g->cflags®_NEWLINE) |
---|
| 751 | CHsub(cs, '\n'); |
---|
| 752 | if (cs->multis != NULL) |
---|
| 753 | mcinvert(p, cs); |
---|
| 754 | } |
---|
| 755 | |
---|
| 756 | assert(cs->multis == NULL); /* xxx */ |
---|
| 757 | |
---|
| 758 | if (nch(p, cs) == 1) { /* optimize singleton sets */ |
---|
| 759 | ordinary(p, firstch(p, cs)); |
---|
| 760 | freeset(p, cs); |
---|
| 761 | } else |
---|
| 762 | EMIT(OANYOF, freezeset(p, cs)); |
---|
| 763 | } |
---|
| 764 | |
---|
| 765 | /* |
---|
| 766 | - p_b_term - parse one term of a bracketed character list |
---|
| 767 | == static void p_b_term(struct parse *p, cset *cs); |
---|
| 768 | */ |
---|
| 769 | static void |
---|
| 770 | p_b_term(p, cs) |
---|
| 771 | struct parse *p; |
---|
| 772 | cset *cs; |
---|
| 773 | { |
---|
| 774 | char c; |
---|
| 775 | char start, finish; |
---|
| 776 | int i; |
---|
| 777 | |
---|
| 778 | /* classify what we've got */ |
---|
| 779 | switch ((MORE()) ? PEEK() : '\0') { |
---|
| 780 | case '[': |
---|
| 781 | c = (MORE2()) ? PEEK2() : '\0'; |
---|
| 782 | break; |
---|
| 783 | case '-': |
---|
| 784 | SETERROR(REG_ERANGE); |
---|
| 785 | return; /* NOTE RETURN */ |
---|
| 786 | break; |
---|
| 787 | default: |
---|
| 788 | c = '\0'; |
---|
| 789 | break; |
---|
| 790 | } |
---|
| 791 | |
---|
| 792 | switch (c) { |
---|
| 793 | case ':': /* character class */ |
---|
| 794 | NEXT2(); |
---|
| 795 | (void)REQUIRE(MORE(), REG_EBRACK); |
---|
| 796 | c = PEEK(); |
---|
| 797 | (void)REQUIRE(c != '-' && c != ']', REG_ECTYPE); |
---|
| 798 | p_b_cclass(p, cs); |
---|
| 799 | (void)REQUIRE(MORE(), REG_EBRACK); |
---|
| 800 | (void)REQUIRE(EATTWO(':', ']'), REG_ECTYPE); |
---|
| 801 | break; |
---|
| 802 | case '=': /* equivalence class */ |
---|
| 803 | NEXT2(); |
---|
| 804 | (void)REQUIRE(MORE(), REG_EBRACK); |
---|
| 805 | c = PEEK(); |
---|
| 806 | (void)REQUIRE(c != '-' && c != ']', REG_ECOLLATE); |
---|
| 807 | p_b_eclass(p, cs); |
---|
| 808 | (void)REQUIRE(MORE(), REG_EBRACK); |
---|
| 809 | (void)REQUIRE(EATTWO('=', ']'), REG_ECOLLATE); |
---|
| 810 | break; |
---|
| 811 | default: /* symbol, ordinary character, or range */ |
---|
| 812 | /* xxx revision needed for multichar stuff */ |
---|
| 813 | start = p_b_symbol(p); |
---|
| 814 | if (SEE('-') && MORE2() && PEEK2() != ']') { |
---|
| 815 | /* range */ |
---|
| 816 | NEXT(); |
---|
| 817 | if (EAT('-')) |
---|
| 818 | finish = '-'; |
---|
| 819 | else |
---|
| 820 | finish = p_b_symbol(p); |
---|
| 821 | } else |
---|
| 822 | finish = start; |
---|
| 823 | if (start == finish) |
---|
| 824 | CHadd(cs, start); |
---|
| 825 | else { |
---|
| 826 | if (__collate_load_error) { |
---|
| 827 | (void)REQUIRE((uch)start <= (uch)finish, REG_ERANGE); |
---|
| 828 | for (i = (uch)start; i <= (uch)finish; i++) |
---|
| 829 | CHadd(cs, i); |
---|
| 830 | } else { |
---|
| 831 | (void)REQUIRE(__collate_range_cmp(start, finish) <= 0, REG_ERANGE); |
---|
| 832 | for (i = CHAR_MIN; i <= CHAR_MAX; i++) { |
---|
| 833 | if ( __collate_range_cmp(start, i) <= 0 |
---|
| 834 | && __collate_range_cmp(i, finish) <= 0 |
---|
| 835 | ) |
---|
| 836 | CHadd(cs, i); |
---|
| 837 | } |
---|
| 838 | } |
---|
| 839 | } |
---|
| 840 | break; |
---|
| 841 | } |
---|
| 842 | } |
---|
| 843 | |
---|
| 844 | /* |
---|
| 845 | - p_b_cclass - parse a character-class name and deal with it |
---|
| 846 | == static void p_b_cclass(struct parse *p, cset *cs); |
---|
| 847 | */ |
---|
| 848 | static void |
---|
| 849 | p_b_cclass(p, cs) |
---|
| 850 | struct parse *p; |
---|
| 851 | cset *cs; |
---|
| 852 | { |
---|
| 853 | int c; |
---|
| 854 | char *sp = p->next; |
---|
| 855 | struct cclass *cp; |
---|
| 856 | size_t len; |
---|
| 857 | |
---|
| 858 | while (MORE() && isalpha((uch)PEEK())) |
---|
| 859 | NEXT(); |
---|
| 860 | len = p->next - sp; |
---|
| 861 | for (cp = cclasses; cp->name != NULL; cp++) |
---|
| 862 | if (strncmp(cp->name, sp, len) == 0 && cp->name[len] == '\0') |
---|
| 863 | break; |
---|
| 864 | if (cp->name == NULL) { |
---|
| 865 | /* oops, didn't find it */ |
---|
| 866 | SETERROR(REG_ECTYPE); |
---|
| 867 | return; |
---|
| 868 | } |
---|
| 869 | |
---|
| 870 | switch (cp->fidx) { |
---|
| 871 | case CALNUM: |
---|
| 872 | for (c = CHAR_MIN; c <= CHAR_MAX; c++) |
---|
| 873 | if (isalnum((uch)c)) |
---|
| 874 | CHadd(cs, c); |
---|
| 875 | break; |
---|
| 876 | case CALPHA: |
---|
| 877 | for (c = CHAR_MIN; c <= CHAR_MAX; c++) |
---|
| 878 | if (isalpha((uch)c)) |
---|
| 879 | CHadd(cs, c); |
---|
| 880 | break; |
---|
| 881 | case CBLANK: |
---|
| 882 | for (c = CHAR_MIN; c <= CHAR_MAX; c++) |
---|
| 883 | if (isblank((uch)c)) |
---|
| 884 | CHadd(cs, c); |
---|
| 885 | break; |
---|
| 886 | case CCNTRL: |
---|
| 887 | for (c = CHAR_MIN; c <= CHAR_MAX; c++) |
---|
| 888 | if (iscntrl((uch)c)) |
---|
| 889 | CHadd(cs, c); |
---|
| 890 | break; |
---|
| 891 | case CDIGIT: |
---|
| 892 | for (c = CHAR_MIN; c <= CHAR_MAX; c++) |
---|
| 893 | if (isdigit((uch)c)) |
---|
| 894 | CHadd(cs, c); |
---|
| 895 | break; |
---|
| 896 | case CGRAPH: |
---|
| 897 | for (c = CHAR_MIN; c <= CHAR_MAX; c++) |
---|
| 898 | if (isgraph((uch)c)) |
---|
| 899 | CHadd(cs, c); |
---|
| 900 | break; |
---|
| 901 | case CLOWER: |
---|
| 902 | for (c = CHAR_MIN; c <= CHAR_MAX; c++) |
---|
| 903 | if (islower((uch)c)) |
---|
| 904 | CHadd(cs, c); |
---|
| 905 | break; |
---|
| 906 | case CPRINT: |
---|
| 907 | for (c = CHAR_MIN; c <= CHAR_MAX; c++) |
---|
| 908 | if (isprint((uch)c)) |
---|
| 909 | CHadd(cs, c); |
---|
| 910 | break; |
---|
| 911 | case CPUNCT: |
---|
| 912 | for (c = CHAR_MIN; c <= CHAR_MAX; c++) |
---|
| 913 | if (ispunct((uch)c)) |
---|
| 914 | CHadd(cs, c); |
---|
| 915 | break; |
---|
| 916 | case CSPACE: |
---|
| 917 | for (c = CHAR_MIN; c <= CHAR_MAX; c++) |
---|
| 918 | if (isspace((uch)c)) |
---|
| 919 | CHadd(cs, c); |
---|
| 920 | break; |
---|
| 921 | case CUPPER: |
---|
| 922 | for (c = CHAR_MIN; c <= CHAR_MAX; c++) |
---|
| 923 | if (isupper((uch)c)) |
---|
| 924 | CHadd(cs, c); |
---|
| 925 | break; |
---|
| 926 | case CXDIGIT: |
---|
| 927 | for (c = CHAR_MIN; c <= CHAR_MAX; c++) |
---|
| 928 | if (isxdigit((uch)c)) |
---|
| 929 | CHadd(cs, c); |
---|
| 930 | break; |
---|
| 931 | } |
---|
| 932 | #if 0 |
---|
| 933 | for (u = cp->multis; *u != '\0'; u += strlen(u) + 1) |
---|
| 934 | MCadd(p, cs, u); |
---|
| 935 | #endif |
---|
| 936 | } |
---|
| 937 | |
---|
| 938 | /* |
---|
| 939 | - p_b_eclass - parse an equivalence-class name and deal with it |
---|
| 940 | == static void p_b_eclass(struct parse *p, cset *cs); |
---|
| 941 | * |
---|
| 942 | * This implementation is incomplete. xxx |
---|
| 943 | */ |
---|
| 944 | static void |
---|
| 945 | p_b_eclass(p, cs) |
---|
| 946 | struct parse *p; |
---|
| 947 | cset *cs; |
---|
| 948 | { |
---|
| 949 | char c; |
---|
| 950 | |
---|
| 951 | c = p_b_coll_elem(p, '='); |
---|
| 952 | CHadd(cs, c); |
---|
| 953 | } |
---|
| 954 | |
---|
| 955 | /* |
---|
| 956 | - p_b_symbol - parse a character or [..]ed multicharacter collating symbol |
---|
| 957 | == static char p_b_symbol(struct parse *p); |
---|
| 958 | */ |
---|
| 959 | static char /* value of symbol */ |
---|
| 960 | p_b_symbol(p) |
---|
| 961 | struct parse *p; |
---|
| 962 | { |
---|
| 963 | char value; |
---|
| 964 | |
---|
| 965 | (void)REQUIRE(MORE(), REG_EBRACK); |
---|
| 966 | if (!EATTWO('[', '.')) |
---|
| 967 | return(GETNEXT()); |
---|
| 968 | |
---|
| 969 | /* collating symbol */ |
---|
| 970 | value = p_b_coll_elem(p, '.'); |
---|
| 971 | (void)REQUIRE(EATTWO('.', ']'), REG_ECOLLATE); |
---|
| 972 | return(value); |
---|
| 973 | } |
---|
| 974 | |
---|
| 975 | /* |
---|
| 976 | - p_b_coll_elem - parse a collating-element name and look it up |
---|
| 977 | == static char p_b_coll_elem(struct parse *p, int endc); |
---|
| 978 | */ |
---|
| 979 | static char /* value of collating element */ |
---|
| 980 | p_b_coll_elem(p, endc) |
---|
| 981 | struct parse *p; |
---|
| 982 | int endc; /* name ended by endc,']' */ |
---|
| 983 | { |
---|
| 984 | char *sp = p->next; |
---|
| 985 | struct cname *cp; |
---|
| 986 | int len; |
---|
| 987 | |
---|
| 988 | while (MORE() && !SEETWO(endc, ']')) |
---|
| 989 | NEXT(); |
---|
| 990 | if (!MORE()) { |
---|
| 991 | SETERROR(REG_EBRACK); |
---|
| 992 | return(0); |
---|
| 993 | } |
---|
| 994 | len = p->next - sp; |
---|
| 995 | for (cp = cnames; cp->name != NULL; cp++) |
---|
| 996 | if (strncmp(cp->name, sp, len) == 0 && cp->name[len] == '\0') |
---|
| 997 | return(cp->code); /* known name */ |
---|
| 998 | if (len == 1) |
---|
| 999 | return(*sp); /* single character */ |
---|
| 1000 | SETERROR(REG_ECOLLATE); /* neither */ |
---|
| 1001 | return(0); |
---|
| 1002 | } |
---|
| 1003 | |
---|
| 1004 | /* |
---|
| 1005 | - othercase - return the case counterpart of an alphabetic |
---|
| 1006 | == static char othercase(int ch); |
---|
| 1007 | */ |
---|
| 1008 | static char /* if no counterpart, return ch */ |
---|
| 1009 | othercase(ch) |
---|
| 1010 | int ch; |
---|
| 1011 | { |
---|
| 1012 | ch = (uch)ch; |
---|
| 1013 | assert(isalpha(ch)); |
---|
| 1014 | if (isupper(ch)) |
---|
| 1015 | return(tolower(ch)); |
---|
| 1016 | else if (islower(ch)) |
---|
| 1017 | return(toupper(ch)); |
---|
| 1018 | else /* peculiar, but could happen */ |
---|
| 1019 | return(ch); |
---|
| 1020 | } |
---|
| 1021 | |
---|
| 1022 | /* |
---|
| 1023 | - bothcases - emit a dualcase version of a two-case character |
---|
| 1024 | == static void bothcases(struct parse *p, int ch); |
---|
| 1025 | * |
---|
| 1026 | * Boy, is this implementation ever a kludge... |
---|
| 1027 | */ |
---|
| 1028 | static void |
---|
| 1029 | bothcases(p, ch) |
---|
| 1030 | struct parse *p; |
---|
| 1031 | int ch; |
---|
| 1032 | { |
---|
| 1033 | char *oldnext = p->next; |
---|
| 1034 | char *oldend = p->end; |
---|
| 1035 | char bracket[3]; |
---|
| 1036 | |
---|
| 1037 | ch = (uch)ch; |
---|
| 1038 | assert(othercase(ch) != ch); /* p_bracket() would recurse */ |
---|
| 1039 | p->next = bracket; |
---|
| 1040 | p->end = bracket+2; |
---|
| 1041 | bracket[0] = ch; |
---|
| 1042 | bracket[1] = ']'; |
---|
| 1043 | bracket[2] = '\0'; |
---|
| 1044 | p_bracket(p); |
---|
| 1045 | assert(p->next == bracket+2); |
---|
| 1046 | p->next = oldnext; |
---|
| 1047 | p->end = oldend; |
---|
| 1048 | } |
---|
| 1049 | |
---|
| 1050 | /* |
---|
| 1051 | - ordinary - emit an ordinary character |
---|
| 1052 | == static void ordinary(struct parse *p, int ch); |
---|
| 1053 | */ |
---|
| 1054 | static void |
---|
| 1055 | ordinary(p, ch) |
---|
| 1056 | struct parse *p; |
---|
| 1057 | int ch; |
---|
| 1058 | { |
---|
| 1059 | cat_t *cap = p->g->categories; |
---|
| 1060 | |
---|
| 1061 | if ((p->g->cflags®_ICASE) && isalpha((uch)ch) && othercase(ch) != ch) |
---|
| 1062 | bothcases(p, ch); |
---|
| 1063 | else { |
---|
| 1064 | EMIT(OCHAR, (uch)ch); |
---|
| 1065 | if (cap[ch] == 0) |
---|
| 1066 | cap[ch] = p->g->ncategories++; |
---|
| 1067 | } |
---|
| 1068 | } |
---|
| 1069 | |
---|
| 1070 | /* |
---|
| 1071 | - nonnewline - emit REG_NEWLINE version of OANY |
---|
| 1072 | == static void nonnewline(struct parse *p); |
---|
| 1073 | * |
---|
| 1074 | * Boy, is this implementation ever a kludge... |
---|
| 1075 | */ |
---|
| 1076 | static void |
---|
| 1077 | nonnewline(p) |
---|
| 1078 | struct parse *p; |
---|
| 1079 | { |
---|
| 1080 | char *oldnext = p->next; |
---|
| 1081 | char *oldend = p->end; |
---|
| 1082 | char bracket[4]; |
---|
| 1083 | |
---|
| 1084 | p->next = bracket; |
---|
| 1085 | p->end = bracket+3; |
---|
| 1086 | bracket[0] = '^'; |
---|
| 1087 | bracket[1] = '\n'; |
---|
| 1088 | bracket[2] = ']'; |
---|
| 1089 | bracket[3] = '\0'; |
---|
| 1090 | p_bracket(p); |
---|
| 1091 | assert(p->next == bracket+3); |
---|
| 1092 | p->next = oldnext; |
---|
| 1093 | p->end = oldend; |
---|
| 1094 | } |
---|
| 1095 | |
---|
| 1096 | /* |
---|
| 1097 | - repeat - generate code for a bounded repetition, recursively if needed |
---|
| 1098 | == static void repeat(struct parse *p, sopno start, int from, int to); |
---|
| 1099 | */ |
---|
| 1100 | static void |
---|
| 1101 | repeat(p, start, from, to) |
---|
| 1102 | struct parse *p; |
---|
| 1103 | sopno start; /* operand from here to end of strip */ |
---|
| 1104 | int from; /* repeated from this number */ |
---|
| 1105 | int to; /* to this number of times (maybe INFINITY) */ |
---|
| 1106 | { |
---|
| 1107 | sopno finish = HERE(); |
---|
| 1108 | # define N 2 |
---|
| 1109 | # define INF 3 |
---|
| 1110 | # define REP(f, t) ((f)*8 + (t)) |
---|
| 1111 | # define MAP(n) (((n) <= 1) ? (n) : ((n) == INFINITY) ? INF : N) |
---|
| 1112 | sopno copy; |
---|
| 1113 | |
---|
| 1114 | if (p->error != 0) /* head off possible runaway recursion */ |
---|
| 1115 | return; |
---|
| 1116 | |
---|
| 1117 | assert(from <= to); |
---|
| 1118 | |
---|
| 1119 | switch (REP(MAP(from), MAP(to))) { |
---|
| 1120 | case REP(0, 0): /* must be user doing this */ |
---|
| 1121 | DROP(finish-start); /* drop the operand */ |
---|
| 1122 | break; |
---|
| 1123 | case REP(0, 1): /* as x{1,1}? */ |
---|
| 1124 | case REP(0, N): /* as x{1,n}? */ |
---|
| 1125 | case REP(0, INF): /* as x{1,}? */ |
---|
| 1126 | /* KLUDGE: emit y? as (y|) until subtle bug gets fixed */ |
---|
| 1127 | INSERT(OCH_, start); /* offset is wrong... */ |
---|
| 1128 | repeat(p, start+1, 1, to); |
---|
| 1129 | ASTERN(OOR1, start); |
---|
| 1130 | AHEAD(start); /* ... fix it */ |
---|
| 1131 | EMIT(OOR2, 0); |
---|
| 1132 | AHEAD(THERE()); |
---|
| 1133 | ASTERN(O_CH, THERETHERE()); |
---|
| 1134 | break; |
---|
| 1135 | case REP(1, 1): /* trivial case */ |
---|
| 1136 | /* done */ |
---|
| 1137 | break; |
---|
| 1138 | case REP(1, N): /* as x?x{1,n-1} */ |
---|
| 1139 | /* KLUDGE: emit y? as (y|) until subtle bug gets fixed */ |
---|
| 1140 | INSERT(OCH_, start); |
---|
| 1141 | ASTERN(OOR1, start); |
---|
| 1142 | AHEAD(start); |
---|
| 1143 | EMIT(OOR2, 0); /* offset very wrong... */ |
---|
| 1144 | AHEAD(THERE()); /* ...so fix it */ |
---|
| 1145 | ASTERN(O_CH, THERETHERE()); |
---|
| 1146 | copy = dupl(p, start+1, finish+1); |
---|
| 1147 | assert(copy == finish+4); |
---|
| 1148 | repeat(p, copy, 1, to-1); |
---|
| 1149 | break; |
---|
| 1150 | case REP(1, INF): /* as x+ */ |
---|
| 1151 | INSERT(OPLUS_, start); |
---|
| 1152 | ASTERN(O_PLUS, start); |
---|
| 1153 | break; |
---|
| 1154 | case REP(N, N): /* as xx{m-1,n-1} */ |
---|
| 1155 | copy = dupl(p, start, finish); |
---|
| 1156 | repeat(p, copy, from-1, to-1); |
---|
| 1157 | break; |
---|
| 1158 | case REP(N, INF): /* as xx{n-1,INF} */ |
---|
| 1159 | copy = dupl(p, start, finish); |
---|
| 1160 | repeat(p, copy, from-1, to); |
---|
| 1161 | break; |
---|
| 1162 | default: /* "can't happen" */ |
---|
| 1163 | SETERROR(REG_ASSERT); /* just in case */ |
---|
| 1164 | break; |
---|
| 1165 | } |
---|
| 1166 | } |
---|
| 1167 | |
---|
| 1168 | /* |
---|
| 1169 | - seterr - set an error condition |
---|
| 1170 | == static int seterr(struct parse *p, int e); |
---|
| 1171 | */ |
---|
| 1172 | static int /* useless but makes type checking happy */ |
---|
| 1173 | seterr(p, e) |
---|
| 1174 | struct parse *p; |
---|
| 1175 | int e; |
---|
| 1176 | { |
---|
| 1177 | if (p->error == 0) /* keep earliest error condition */ |
---|
| 1178 | p->error = e; |
---|
| 1179 | p->next = nuls; /* try to bring things to a halt */ |
---|
| 1180 | p->end = nuls; |
---|
| 1181 | return(0); /* make the return value well-defined */ |
---|
| 1182 | } |
---|
| 1183 | |
---|
| 1184 | /* |
---|
| 1185 | - allocset - allocate a set of characters for [] |
---|
| 1186 | == static cset *allocset(struct parse *p); |
---|
| 1187 | */ |
---|
| 1188 | static cset * |
---|
| 1189 | allocset(p) |
---|
| 1190 | struct parse *p; |
---|
| 1191 | { |
---|
| 1192 | int no = p->g->ncsets++; |
---|
| 1193 | size_t nc; |
---|
| 1194 | size_t nbytes; |
---|
| 1195 | cset *cs; |
---|
| 1196 | size_t css = (size_t)p->g->csetsize; |
---|
| 1197 | int i; |
---|
| 1198 | |
---|
| 1199 | if (no >= p->ncsalloc) { /* need another column of space */ |
---|
| 1200 | p->ncsalloc += CHAR_BIT; |
---|
| 1201 | nc = p->ncsalloc; |
---|
| 1202 | assert(nc % CHAR_BIT == 0); |
---|
| 1203 | nbytes = nc / CHAR_BIT * css; |
---|
| 1204 | if (p->g->sets == NULL) |
---|
| 1205 | p->g->sets = (cset *)malloc(nc * sizeof(cset)); |
---|
| 1206 | else |
---|
| 1207 | p->g->sets = (cset *)reallocf((char *)p->g->sets, |
---|
| 1208 | nc * sizeof(cset)); |
---|
| 1209 | if (p->g->setbits == NULL) |
---|
| 1210 | p->g->setbits = (uch *)malloc(nbytes); |
---|
| 1211 | else { |
---|
| 1212 | p->g->setbits = (uch *)reallocf((char *)p->g->setbits, |
---|
| 1213 | nbytes); |
---|
| 1214 | /* xxx this isn't right if setbits is now NULL */ |
---|
| 1215 | for (i = 0; i < no; i++) |
---|
| 1216 | p->g->sets[i].ptr = p->g->setbits + css*(i/CHAR_BIT); |
---|
| 1217 | } |
---|
| 1218 | if (p->g->sets != NULL && p->g->setbits != NULL) |
---|
| 1219 | (void) memset((char *)p->g->setbits + (nbytes - css), |
---|
| 1220 | 0, css); |
---|
| 1221 | else { |
---|
| 1222 | no = 0; |
---|
| 1223 | SETERROR(REG_ESPACE); |
---|
| 1224 | /* caller's responsibility not to do set ops */ |
---|
| 1225 | } |
---|
| 1226 | } |
---|
| 1227 | |
---|
| 1228 | assert(p->g->sets != NULL); /* xxx */ |
---|
| 1229 | cs = &p->g->sets[no]; |
---|
| 1230 | cs->ptr = p->g->setbits + css*((no)/CHAR_BIT); |
---|
| 1231 | cs->mask = 1 << ((no) % CHAR_BIT); |
---|
| 1232 | cs->hash = 0; |
---|
| 1233 | cs->smultis = 0; |
---|
| 1234 | cs->multis = NULL; |
---|
| 1235 | |
---|
| 1236 | return(cs); |
---|
| 1237 | } |
---|
| 1238 | |
---|
| 1239 | /* |
---|
| 1240 | - freeset - free a now-unused set |
---|
| 1241 | == static void freeset(struct parse *p, cset *cs); |
---|
| 1242 | */ |
---|
| 1243 | static void |
---|
| 1244 | freeset(p, cs) |
---|
| 1245 | struct parse *p; |
---|
| 1246 | cset *cs; |
---|
| 1247 | { |
---|
| 1248 | int i; |
---|
| 1249 | cset *top = &p->g->sets[p->g->ncsets]; |
---|
| 1250 | size_t css = (size_t)p->g->csetsize; |
---|
| 1251 | |
---|
| 1252 | for (i = 0; i < css; i++) |
---|
| 1253 | CHsub(cs, i); |
---|
| 1254 | if (cs == top-1) /* recover only the easy case */ |
---|
| 1255 | p->g->ncsets--; |
---|
| 1256 | } |
---|
| 1257 | |
---|
| 1258 | /* |
---|
| 1259 | - freezeset - final processing on a set of characters |
---|
| 1260 | == static int freezeset(struct parse *p, cset *cs); |
---|
| 1261 | * |
---|
| 1262 | * The main task here is merging identical sets. This is usually a waste |
---|
| 1263 | * of time (although the hash code minimizes the overhead), but can win |
---|
| 1264 | * big if REG_ICASE is being used. REG_ICASE, by the way, is why the hash |
---|
| 1265 | * is done using addition rather than xor -- all ASCII [aA] sets xor to |
---|
| 1266 | * the same value! |
---|
| 1267 | */ |
---|
| 1268 | static int /* set number */ |
---|
| 1269 | freezeset(p, cs) |
---|
| 1270 | struct parse *p; |
---|
| 1271 | cset *cs; |
---|
| 1272 | { |
---|
| 1273 | short h = cs->hash; |
---|
| 1274 | int i; |
---|
| 1275 | cset *top = &p->g->sets[p->g->ncsets]; |
---|
| 1276 | cset *cs2; |
---|
| 1277 | size_t css = (size_t)p->g->csetsize; |
---|
| 1278 | |
---|
| 1279 | /* look for an earlier one which is the same */ |
---|
| 1280 | for (cs2 = &p->g->sets[0]; cs2 < top; cs2++) |
---|
| 1281 | if (cs2->hash == h && cs2 != cs) { |
---|
| 1282 | /* maybe */ |
---|
| 1283 | for (i = 0; i < css; i++) |
---|
| 1284 | if (!!CHIN(cs2, i) != !!CHIN(cs, i)) |
---|
| 1285 | break; /* no */ |
---|
| 1286 | if (i == css) |
---|
| 1287 | break; /* yes */ |
---|
| 1288 | } |
---|
| 1289 | |
---|
| 1290 | if (cs2 < top) { /* found one */ |
---|
| 1291 | freeset(p, cs); |
---|
| 1292 | cs = cs2; |
---|
| 1293 | } |
---|
| 1294 | |
---|
| 1295 | return((int)(cs - p->g->sets)); |
---|
| 1296 | } |
---|
| 1297 | |
---|
| 1298 | /* |
---|
| 1299 | - firstch - return first character in a set (which must have at least one) |
---|
| 1300 | == static int firstch(struct parse *p, cset *cs); |
---|
| 1301 | */ |
---|
| 1302 | static int /* character; there is no "none" value */ |
---|
| 1303 | firstch(p, cs) |
---|
| 1304 | struct parse *p; |
---|
| 1305 | cset *cs; |
---|
| 1306 | { |
---|
| 1307 | int i; |
---|
| 1308 | size_t css = (size_t)p->g->csetsize; |
---|
| 1309 | |
---|
| 1310 | for (i = 0; i < css; i++) |
---|
| 1311 | if (CHIN(cs, i)) |
---|
| 1312 | return((char)i); |
---|
| 1313 | assert(never); |
---|
| 1314 | return(0); /* arbitrary */ |
---|
| 1315 | } |
---|
| 1316 | |
---|
| 1317 | /* |
---|
| 1318 | - nch - number of characters in a set |
---|
| 1319 | == static int nch(struct parse *p, cset *cs); |
---|
| 1320 | */ |
---|
| 1321 | static int |
---|
| 1322 | nch(p, cs) |
---|
| 1323 | struct parse *p; |
---|
| 1324 | cset *cs; |
---|
| 1325 | { |
---|
| 1326 | int i; |
---|
| 1327 | size_t css = (size_t)p->g->csetsize; |
---|
| 1328 | int n = 0; |
---|
| 1329 | |
---|
| 1330 | for (i = 0; i < css; i++) |
---|
| 1331 | if (CHIN(cs, i)) |
---|
| 1332 | n++; |
---|
| 1333 | return(n); |
---|
| 1334 | } |
---|
| 1335 | |
---|
| 1336 | #if used |
---|
| 1337 | /* |
---|
| 1338 | - mcadd - add a collating element to a cset |
---|
| 1339 | == static void mcadd(struct parse *p, cset *cs, \ |
---|
| 1340 | == char *cp); |
---|
| 1341 | */ |
---|
| 1342 | static void |
---|
| 1343 | mcadd(p, cs, cp) |
---|
| 1344 | struct parse *p; |
---|
| 1345 | cset *cs; |
---|
| 1346 | char *cp; |
---|
| 1347 | { |
---|
| 1348 | size_t oldend = cs->smultis; |
---|
| 1349 | |
---|
| 1350 | cs->smultis += strlen(cp) + 1; |
---|
| 1351 | if (cs->multis == NULL) |
---|
| 1352 | cs->multis = malloc(cs->smultis); |
---|
| 1353 | else |
---|
| 1354 | cs->multis = reallocf(cs->multis, cs->smultis); |
---|
| 1355 | if (cs->multis == NULL) { |
---|
| 1356 | SETERROR(REG_ESPACE); |
---|
| 1357 | return; |
---|
| 1358 | } |
---|
| 1359 | |
---|
| 1360 | (void) strcpy(cs->multis + oldend - 1, cp); |
---|
| 1361 | cs->multis[cs->smultis - 1] = '\0'; |
---|
| 1362 | } |
---|
| 1363 | |
---|
| 1364 | /* |
---|
| 1365 | - mcsub - subtract a collating element from a cset |
---|
| 1366 | == static void mcsub(cset *cs, char *cp); |
---|
| 1367 | */ |
---|
| 1368 | static void |
---|
| 1369 | mcsub(cs, cp) |
---|
| 1370 | cset *cs; |
---|
| 1371 | char *cp; |
---|
| 1372 | { |
---|
| 1373 | char *fp = mcfind(cs, cp); |
---|
| 1374 | size_t len = strlen(fp); |
---|
| 1375 | |
---|
| 1376 | assert(fp != NULL); |
---|
| 1377 | (void) memmove(fp, fp + len + 1, |
---|
| 1378 | cs->smultis - (fp + len + 1 - cs->multis)); |
---|
| 1379 | cs->smultis -= len; |
---|
| 1380 | |
---|
| 1381 | if (cs->smultis == 0) { |
---|
| 1382 | free(cs->multis); |
---|
| 1383 | cs->multis = NULL; |
---|
| 1384 | return; |
---|
| 1385 | } |
---|
| 1386 | |
---|
| 1387 | cs->multis = reallocf(cs->multis, cs->smultis); |
---|
| 1388 | assert(cs->multis != NULL); |
---|
| 1389 | } |
---|
| 1390 | |
---|
| 1391 | /* |
---|
| 1392 | - mcin - is a collating element in a cset? |
---|
| 1393 | == static int mcin(cset *cs, char *cp); |
---|
| 1394 | */ |
---|
| 1395 | static int |
---|
| 1396 | mcin(cs, cp) |
---|
| 1397 | cset *cs; |
---|
| 1398 | char *cp; |
---|
| 1399 | { |
---|
| 1400 | return(mcfind(cs, cp) != NULL); |
---|
| 1401 | } |
---|
| 1402 | |
---|
| 1403 | /* |
---|
| 1404 | - mcfind - find a collating element in a cset |
---|
| 1405 | == static char *mcfind(cset *cs, char *cp); |
---|
| 1406 | */ |
---|
| 1407 | static char * |
---|
| 1408 | mcfind(cs, cp) |
---|
| 1409 | cset *cs; |
---|
| 1410 | char *cp; |
---|
| 1411 | { |
---|
| 1412 | char *p; |
---|
| 1413 | |
---|
| 1414 | if (cs->multis == NULL) |
---|
| 1415 | return(NULL); |
---|
| 1416 | for (p = cs->multis; *p != '\0'; p += strlen(p) + 1) |
---|
| 1417 | if (strcmp(cp, p) == 0) |
---|
| 1418 | return(p); |
---|
| 1419 | return(NULL); |
---|
| 1420 | } |
---|
| 1421 | #endif |
---|
| 1422 | |
---|
| 1423 | /* |
---|
| 1424 | - mcinvert - invert the list of collating elements in a cset |
---|
| 1425 | == static void mcinvert(struct parse *p, cset *cs); |
---|
| 1426 | * |
---|
| 1427 | * This would have to know the set of possibilities. Implementation |
---|
| 1428 | * is deferred. |
---|
| 1429 | */ |
---|
| 1430 | static void |
---|
| 1431 | mcinvert(p, cs) |
---|
| 1432 | struct parse *p; |
---|
| 1433 | cset *cs; |
---|
| 1434 | { |
---|
| 1435 | assert(cs->multis == NULL); /* xxx */ |
---|
| 1436 | } |
---|
| 1437 | |
---|
| 1438 | /* |
---|
| 1439 | - mccase - add case counterparts of the list of collating elements in a cset |
---|
| 1440 | == static void mccase(struct parse *p, cset *cs); |
---|
| 1441 | * |
---|
| 1442 | * This would have to know the set of possibilities. Implementation |
---|
| 1443 | * is deferred. |
---|
| 1444 | */ |
---|
| 1445 | static void |
---|
| 1446 | mccase(p, cs) |
---|
| 1447 | struct parse *p; |
---|
| 1448 | cset *cs; |
---|
| 1449 | { |
---|
| 1450 | assert(cs->multis == NULL); /* xxx */ |
---|
| 1451 | } |
---|
| 1452 | |
---|
| 1453 | /* |
---|
| 1454 | - isinsets - is this character in any sets? |
---|
| 1455 | == static int isinsets(struct re_guts *g, int c); |
---|
| 1456 | */ |
---|
| 1457 | static int /* predicate */ |
---|
| 1458 | isinsets(g, c) |
---|
| 1459 | struct re_guts *g; |
---|
| 1460 | int c; |
---|
| 1461 | { |
---|
| 1462 | uch *col; |
---|
| 1463 | int i; |
---|
| 1464 | int ncols = (g->ncsets+(CHAR_BIT-1)) / CHAR_BIT; |
---|
| 1465 | unsigned uc = (uch)c; |
---|
| 1466 | |
---|
| 1467 | for (i = 0, col = g->setbits; i < ncols; i++, col += g->csetsize) |
---|
| 1468 | if (col[uc] != 0) |
---|
| 1469 | return(1); |
---|
| 1470 | return(0); |
---|
| 1471 | } |
---|
| 1472 | |
---|
| 1473 | /* |
---|
| 1474 | - samesets - are these two characters in exactly the same sets? |
---|
| 1475 | == static int samesets(struct re_guts *g, int c1, int c2); |
---|
| 1476 | */ |
---|
| 1477 | static int /* predicate */ |
---|
| 1478 | samesets(g, c1, c2) |
---|
| 1479 | struct re_guts *g; |
---|
| 1480 | int c1; |
---|
| 1481 | int c2; |
---|
| 1482 | { |
---|
| 1483 | uch *col; |
---|
| 1484 | int i; |
---|
| 1485 | int ncols = (g->ncsets+(CHAR_BIT-1)) / CHAR_BIT; |
---|
| 1486 | unsigned uc1 = (uch)c1; |
---|
| 1487 | unsigned uc2 = (uch)c2; |
---|
| 1488 | |
---|
| 1489 | for (i = 0, col = g->setbits; i < ncols; i++, col += g->csetsize) |
---|
| 1490 | if (col[uc1] != col[uc2]) |
---|
| 1491 | return(0); |
---|
| 1492 | return(1); |
---|
| 1493 | } |
---|
| 1494 | |
---|
| 1495 | /* |
---|
| 1496 | - categorize - sort out character categories |
---|
| 1497 | == static void categorize(struct parse *p, struct re_guts *g); |
---|
| 1498 | */ |
---|
| 1499 | static void |
---|
| 1500 | categorize(p, g) |
---|
| 1501 | struct parse *p; |
---|
| 1502 | struct re_guts *g; |
---|
| 1503 | { |
---|
| 1504 | cat_t *cats = g->categories; |
---|
| 1505 | int c; |
---|
| 1506 | int c2; |
---|
| 1507 | cat_t cat; |
---|
| 1508 | |
---|
| 1509 | /* avoid making error situations worse */ |
---|
| 1510 | if (p->error != 0) |
---|
| 1511 | return; |
---|
| 1512 | |
---|
| 1513 | for (c = CHAR_MIN; c <= CHAR_MAX; c++) |
---|
| 1514 | if (cats[c] == 0 && isinsets(g, c)) { |
---|
| 1515 | cat = g->ncategories++; |
---|
| 1516 | cats[c] = cat; |
---|
| 1517 | for (c2 = c+1; c2 <= CHAR_MAX; c2++) |
---|
| 1518 | if (cats[c2] == 0 && samesets(g, c, c2)) |
---|
| 1519 | cats[c2] = cat; |
---|
| 1520 | } |
---|
| 1521 | } |
---|
| 1522 | |
---|
| 1523 | /* |
---|
| 1524 | - dupl - emit a duplicate of a bunch of sops |
---|
| 1525 | == static sopno dupl(struct parse *p, sopno start, sopno finish); |
---|
| 1526 | */ |
---|
| 1527 | static sopno /* start of duplicate */ |
---|
| 1528 | dupl(p, start, finish) |
---|
| 1529 | struct parse *p; |
---|
| 1530 | sopno start; /* from here */ |
---|
| 1531 | sopno finish; /* to this less one */ |
---|
| 1532 | { |
---|
| 1533 | sopno ret = HERE(); |
---|
| 1534 | sopno len = finish - start; |
---|
| 1535 | |
---|
| 1536 | assert(finish >= start); |
---|
| 1537 | if (len == 0) |
---|
| 1538 | return(ret); |
---|
| 1539 | enlarge(p, p->ssize + len); /* this many unexpected additions */ |
---|
| 1540 | assert(p->ssize >= p->slen + len); |
---|
| 1541 | (void) memcpy((char *)(p->strip + p->slen), |
---|
| 1542 | (char *)(p->strip + start), (size_t)len*sizeof(sop)); |
---|
| 1543 | p->slen += len; |
---|
| 1544 | return(ret); |
---|
| 1545 | } |
---|
| 1546 | |
---|
| 1547 | /* |
---|
| 1548 | - doemit - emit a strip operator |
---|
| 1549 | == static void doemit(struct parse *p, sop op, size_t opnd); |
---|
| 1550 | * |
---|
| 1551 | * It might seem better to implement this as a macro with a function as |
---|
| 1552 | * hard-case backup, but it's just too big and messy unless there are |
---|
| 1553 | * some changes to the data structures. Maybe later. |
---|
| 1554 | */ |
---|
| 1555 | static void |
---|
| 1556 | doemit(p, op, opnd) |
---|
| 1557 | struct parse *p; |
---|
| 1558 | sop op; |
---|
| 1559 | size_t opnd; |
---|
| 1560 | { |
---|
| 1561 | /* avoid making error situations worse */ |
---|
| 1562 | if (p->error != 0) |
---|
| 1563 | return; |
---|
| 1564 | |
---|
| 1565 | /* deal with oversize operands ("can't happen", more or less) */ |
---|
| 1566 | assert(opnd < 1<<OPSHIFT); |
---|
| 1567 | |
---|
| 1568 | /* deal with undersized strip */ |
---|
| 1569 | if (p->slen >= p->ssize) |
---|
| 1570 | enlarge(p, (p->ssize+1) / 2 * 3); /* +50% */ |
---|
| 1571 | assert(p->slen < p->ssize); |
---|
| 1572 | |
---|
| 1573 | /* finally, it's all reduced to the easy case */ |
---|
| 1574 | p->strip[p->slen++] = SOP(op, opnd); |
---|
| 1575 | } |
---|
| 1576 | |
---|
| 1577 | /* |
---|
| 1578 | - doinsert - insert a sop into the strip |
---|
| 1579 | == static void doinsert(struct parse *p, sop op, size_t opnd, sopno pos); |
---|
| 1580 | */ |
---|
| 1581 | static void |
---|
| 1582 | doinsert(p, op, opnd, pos) |
---|
| 1583 | struct parse *p; |
---|
| 1584 | sop op; |
---|
| 1585 | size_t opnd; |
---|
| 1586 | sopno pos; |
---|
| 1587 | { |
---|
| 1588 | sopno sn; |
---|
| 1589 | sop s; |
---|
| 1590 | int i; |
---|
| 1591 | |
---|
| 1592 | /* avoid making error situations worse */ |
---|
| 1593 | if (p->error != 0) |
---|
| 1594 | return; |
---|
| 1595 | |
---|
| 1596 | sn = HERE(); |
---|
| 1597 | EMIT(op, opnd); /* do checks, ensure space */ |
---|
| 1598 | assert(HERE() == sn+1); |
---|
| 1599 | s = p->strip[sn]; |
---|
| 1600 | |
---|
| 1601 | /* adjust paren pointers */ |
---|
| 1602 | assert(pos > 0); |
---|
| 1603 | for (i = 1; i < NPAREN; i++) { |
---|
| 1604 | if (p->pbegin[i] >= pos) { |
---|
| 1605 | p->pbegin[i]++; |
---|
| 1606 | } |
---|
| 1607 | if (p->pend[i] >= pos) { |
---|
| 1608 | p->pend[i]++; |
---|
| 1609 | } |
---|
| 1610 | } |
---|
| 1611 | |
---|
| 1612 | memmove((char *)&p->strip[pos+1], (char *)&p->strip[pos], |
---|
| 1613 | (HERE()-pos-1)*sizeof(sop)); |
---|
| 1614 | p->strip[pos] = s; |
---|
| 1615 | } |
---|
| 1616 | |
---|
| 1617 | /* |
---|
| 1618 | - dofwd - complete a forward reference |
---|
| 1619 | == static void dofwd(struct parse *p, sopno pos, sop value); |
---|
| 1620 | */ |
---|
| 1621 | static void |
---|
| 1622 | dofwd(p, pos, value) |
---|
| 1623 | struct parse *p; |
---|
| 1624 | sopno pos; |
---|
| 1625 | sop value; |
---|
| 1626 | { |
---|
| 1627 | /* avoid making error situations worse */ |
---|
| 1628 | if (p->error != 0) |
---|
| 1629 | return; |
---|
| 1630 | |
---|
| 1631 | assert(value < 1<<OPSHIFT); |
---|
| 1632 | p->strip[pos] = OP(p->strip[pos]) | value; |
---|
| 1633 | } |
---|
| 1634 | |
---|
| 1635 | /* |
---|
| 1636 | - enlarge - enlarge the strip |
---|
| 1637 | == static void enlarge(struct parse *p, sopno size); |
---|
| 1638 | */ |
---|
| 1639 | static void |
---|
| 1640 | enlarge(p, size) |
---|
| 1641 | struct parse *p; |
---|
| 1642 | sopno size; |
---|
| 1643 | { |
---|
| 1644 | sop *sp; |
---|
| 1645 | |
---|
| 1646 | if (p->ssize >= size) |
---|
| 1647 | return; |
---|
| 1648 | |
---|
| 1649 | sp = (sop *)realloc(p->strip, size*sizeof(sop)); |
---|
| 1650 | if (sp == NULL) { |
---|
| 1651 | SETERROR(REG_ESPACE); |
---|
| 1652 | return; |
---|
| 1653 | } |
---|
| 1654 | p->strip = sp; |
---|
| 1655 | p->ssize = size; |
---|
| 1656 | } |
---|
| 1657 | |
---|
| 1658 | /* |
---|
| 1659 | - stripsnug - compact the strip |
---|
| 1660 | == static void stripsnug(struct parse *p, struct re_guts *g); |
---|
| 1661 | */ |
---|
| 1662 | static void |
---|
| 1663 | stripsnug(p, g) |
---|
| 1664 | struct parse *p; |
---|
| 1665 | struct re_guts *g; |
---|
| 1666 | { |
---|
| 1667 | g->nstates = p->slen; |
---|
| 1668 | g->strip = (sop *)realloc((char *)p->strip, p->slen * sizeof(sop)); |
---|
| 1669 | if (g->strip == NULL) { |
---|
| 1670 | SETERROR(REG_ESPACE); |
---|
| 1671 | g->strip = p->strip; |
---|
| 1672 | } |
---|
| 1673 | } |
---|
| 1674 | |
---|
| 1675 | /* |
---|
| 1676 | - findmust - fill in must and mlen with longest mandatory literal string |
---|
| 1677 | == static void findmust(struct parse *p, struct re_guts *g); |
---|
| 1678 | * |
---|
| 1679 | * This algorithm could do fancy things like analyzing the operands of | |
---|
| 1680 | * for common subsequences. Someday. This code is simple and finds most |
---|
| 1681 | * of the interesting cases. |
---|
| 1682 | * |
---|
| 1683 | * Note that must and mlen got initialized during setup. |
---|
| 1684 | */ |
---|
| 1685 | static void |
---|
| 1686 | findmust(p, g) |
---|
| 1687 | struct parse *p; |
---|
| 1688 | struct re_guts *g; |
---|
| 1689 | { |
---|
| 1690 | sop *scan; |
---|
| 1691 | sop *start = NULL; |
---|
| 1692 | sop *newstart = NULL; |
---|
| 1693 | sopno newlen; |
---|
| 1694 | sop s; |
---|
| 1695 | char *cp; |
---|
| 1696 | sopno i; |
---|
| 1697 | int offset; |
---|
| 1698 | int cs, mccs; |
---|
| 1699 | |
---|
| 1700 | /* avoid making error situations worse */ |
---|
| 1701 | if (p->error != 0) |
---|
| 1702 | return; |
---|
| 1703 | |
---|
| 1704 | /* Find out if we can handle OANYOF or not */ |
---|
| 1705 | mccs = 0; |
---|
| 1706 | for (cs = 0; cs < g->ncsets; cs++) |
---|
| 1707 | if (g->sets[cs].multis != NULL) |
---|
| 1708 | mccs = 1; |
---|
| 1709 | |
---|
| 1710 | /* find the longest OCHAR sequence in strip */ |
---|
| 1711 | newlen = 0; |
---|
| 1712 | offset = 0; |
---|
| 1713 | g->moffset = 0; |
---|
| 1714 | scan = g->strip + 1; |
---|
| 1715 | do { |
---|
| 1716 | s = *scan++; |
---|
| 1717 | switch (OP(s)) { |
---|
| 1718 | case OCHAR: /* sequence member */ |
---|
| 1719 | if (newlen == 0) /* new sequence */ |
---|
| 1720 | newstart = scan - 1; |
---|
| 1721 | newlen++; |
---|
| 1722 | break; |
---|
| 1723 | case OPLUS_: /* things that don't break one */ |
---|
| 1724 | case OLPAREN: |
---|
| 1725 | case ORPAREN: |
---|
| 1726 | break; |
---|
| 1727 | case OQUEST_: /* things that must be skipped */ |
---|
| 1728 | case OCH_: |
---|
| 1729 | offset = altoffset(scan, offset, mccs); |
---|
| 1730 | scan--; |
---|
| 1731 | do { |
---|
| 1732 | scan += OPND(s); |
---|
| 1733 | s = *scan; |
---|
| 1734 | /* assert() interferes w debug printouts */ |
---|
| 1735 | if (OP(s) != O_QUEST && OP(s) != O_CH && |
---|
| 1736 | OP(s) != OOR2) { |
---|
| 1737 | g->iflags |= BAD; |
---|
| 1738 | return; |
---|
| 1739 | } |
---|
| 1740 | } while (OP(s) != O_QUEST && OP(s) != O_CH); |
---|
| 1741 | /* fallthrough */ |
---|
| 1742 | case OBOW: /* things that break a sequence */ |
---|
| 1743 | case OEOW: |
---|
| 1744 | case OBOL: |
---|
| 1745 | case OEOL: |
---|
| 1746 | case O_QUEST: |
---|
| 1747 | case O_CH: |
---|
| 1748 | case OEND: |
---|
| 1749 | if (newlen > g->mlen) { /* ends one */ |
---|
| 1750 | start = newstart; |
---|
| 1751 | g->mlen = newlen; |
---|
| 1752 | if (offset > -1) { |
---|
| 1753 | g->moffset += offset; |
---|
| 1754 | offset = newlen; |
---|
| 1755 | } else |
---|
| 1756 | g->moffset = offset; |
---|
| 1757 | } else { |
---|
| 1758 | if (offset > -1) |
---|
| 1759 | offset += newlen; |
---|
| 1760 | } |
---|
| 1761 | newlen = 0; |
---|
| 1762 | break; |
---|
| 1763 | case OANY: |
---|
| 1764 | if (newlen > g->mlen) { /* ends one */ |
---|
| 1765 | start = newstart; |
---|
| 1766 | g->mlen = newlen; |
---|
| 1767 | if (offset > -1) { |
---|
| 1768 | g->moffset += offset; |
---|
| 1769 | offset = newlen; |
---|
| 1770 | } else |
---|
| 1771 | g->moffset = offset; |
---|
| 1772 | } else { |
---|
| 1773 | if (offset > -1) |
---|
| 1774 | offset += newlen; |
---|
| 1775 | } |
---|
| 1776 | if (offset > -1) |
---|
| 1777 | offset++; |
---|
| 1778 | newlen = 0; |
---|
| 1779 | break; |
---|
| 1780 | case OANYOF: /* may or may not invalidate offset */ |
---|
| 1781 | /* First, everything as OANY */ |
---|
| 1782 | if (newlen > g->mlen) { /* ends one */ |
---|
| 1783 | start = newstart; |
---|
| 1784 | g->mlen = newlen; |
---|
| 1785 | if (offset > -1) { |
---|
| 1786 | g->moffset += offset; |
---|
| 1787 | offset = newlen; |
---|
| 1788 | } else |
---|
| 1789 | g->moffset = offset; |
---|
| 1790 | } else { |
---|
| 1791 | if (offset > -1) |
---|
| 1792 | offset += newlen; |
---|
| 1793 | } |
---|
| 1794 | if (offset > -1) |
---|
| 1795 | offset++; |
---|
| 1796 | newlen = 0; |
---|
| 1797 | /* And, now, if we found out we can't deal with |
---|
| 1798 | * it, make offset = -1. |
---|
| 1799 | */ |
---|
| 1800 | if (mccs) |
---|
| 1801 | offset = -1; |
---|
| 1802 | break; |
---|
| 1803 | default: |
---|
| 1804 | /* Anything here makes it impossible or too hard |
---|
| 1805 | * to calculate the offset -- so we give up; |
---|
| 1806 | * save the last known good offset, in case the |
---|
| 1807 | * must sequence doesn't occur later. |
---|
| 1808 | */ |
---|
| 1809 | if (newlen > g->mlen) { /* ends one */ |
---|
| 1810 | start = newstart; |
---|
| 1811 | g->mlen = newlen; |
---|
| 1812 | if (offset > -1) |
---|
| 1813 | g->moffset += offset; |
---|
| 1814 | else |
---|
| 1815 | g->moffset = offset; |
---|
| 1816 | } |
---|
| 1817 | offset = -1; |
---|
| 1818 | newlen = 0; |
---|
| 1819 | break; |
---|
| 1820 | } |
---|
| 1821 | } while (OP(s) != OEND); |
---|
| 1822 | |
---|
| 1823 | if (g->mlen == 0) { /* there isn't one */ |
---|
| 1824 | g->moffset = -1; |
---|
| 1825 | return; |
---|
| 1826 | } |
---|
| 1827 | |
---|
| 1828 | /* turn it into a character string */ |
---|
| 1829 | g->must = malloc((size_t)g->mlen + 1); |
---|
| 1830 | if (g->must == NULL) { /* argh; just forget it */ |
---|
| 1831 | g->mlen = 0; |
---|
| 1832 | g->moffset = -1; |
---|
| 1833 | return; |
---|
| 1834 | } |
---|
| 1835 | cp = g->must; |
---|
| 1836 | scan = start; |
---|
| 1837 | for (i = g->mlen; i > 0; i--) { |
---|
| 1838 | while (OP(s = *scan++) != OCHAR) |
---|
| 1839 | continue; |
---|
| 1840 | assert(cp < g->must + g->mlen); |
---|
| 1841 | *cp++ = (char)OPND(s); |
---|
| 1842 | } |
---|
| 1843 | assert(cp == g->must + g->mlen); |
---|
| 1844 | *cp++ = '\0'; /* just on general principles */ |
---|
| 1845 | } |
---|
| 1846 | |
---|
| 1847 | /* |
---|
| 1848 | - altoffset - choose biggest offset among multiple choices |
---|
| 1849 | == static int altoffset(sop *scan, int offset, int mccs); |
---|
| 1850 | * |
---|
| 1851 | * Compute, recursively if necessary, the largest offset among multiple |
---|
| 1852 | * re paths. |
---|
| 1853 | */ |
---|
| 1854 | static int |
---|
| 1855 | altoffset(scan, offset, mccs) |
---|
| 1856 | sop *scan; |
---|
| 1857 | int offset; |
---|
| 1858 | int mccs; |
---|
| 1859 | { |
---|
| 1860 | int largest; |
---|
| 1861 | int try; |
---|
| 1862 | sop s; |
---|
| 1863 | |
---|
| 1864 | /* If we gave up already on offsets, return */ |
---|
| 1865 | if (offset == -1) |
---|
| 1866 | return -1; |
---|
| 1867 | |
---|
| 1868 | largest = 0; |
---|
| 1869 | try = 0; |
---|
| 1870 | s = *scan++; |
---|
| 1871 | while (OP(s) != O_QUEST && OP(s) != O_CH) { |
---|
| 1872 | switch (OP(s)) { |
---|
| 1873 | case OOR1: |
---|
| 1874 | if (try > largest) |
---|
| 1875 | largest = try; |
---|
| 1876 | try = 0; |
---|
| 1877 | break; |
---|
| 1878 | case OQUEST_: |
---|
| 1879 | case OCH_: |
---|
| 1880 | try = altoffset(scan, try, mccs); |
---|
| 1881 | if (try == -1) |
---|
| 1882 | return -1; |
---|
| 1883 | scan--; |
---|
| 1884 | do { |
---|
| 1885 | scan += OPND(s); |
---|
| 1886 | s = *scan; |
---|
| 1887 | if (OP(s) != O_QUEST && OP(s) != O_CH && |
---|
| 1888 | OP(s) != OOR2) |
---|
| 1889 | return -1; |
---|
| 1890 | } while (OP(s) != O_QUEST && OP(s) != O_CH); |
---|
| 1891 | /* We must skip to the next position, or we'll |
---|
| 1892 | * leave altoffset() too early. |
---|
| 1893 | */ |
---|
| 1894 | scan++; |
---|
| 1895 | break; |
---|
| 1896 | case OANYOF: |
---|
| 1897 | if (mccs) |
---|
| 1898 | return -1; |
---|
| 1899 | case OCHAR: |
---|
| 1900 | case OANY: |
---|
| 1901 | try++; |
---|
| 1902 | case OBOW: |
---|
| 1903 | case OEOW: |
---|
| 1904 | case OLPAREN: |
---|
| 1905 | case ORPAREN: |
---|
| 1906 | case OOR2: |
---|
| 1907 | break; |
---|
| 1908 | default: |
---|
| 1909 | try = -1; |
---|
| 1910 | break; |
---|
| 1911 | } |
---|
| 1912 | if (try == -1) |
---|
| 1913 | return -1; |
---|
| 1914 | s = *scan++; |
---|
| 1915 | } |
---|
| 1916 | |
---|
| 1917 | if (try > largest) |
---|
| 1918 | largest = try; |
---|
| 1919 | |
---|
| 1920 | return largest+offset; |
---|
| 1921 | } |
---|
| 1922 | |
---|
| 1923 | /* |
---|
| 1924 | - computejumps - compute char jumps for BM scan |
---|
| 1925 | == static void computejumps(struct parse *p, struct re_guts *g); |
---|
| 1926 | * |
---|
| 1927 | * This algorithm assumes g->must exists and is has size greater than |
---|
| 1928 | * zero. It's based on the algorithm found on Computer Algorithms by |
---|
| 1929 | * Sara Baase. |
---|
| 1930 | * |
---|
| 1931 | * A char jump is the number of characters one needs to jump based on |
---|
| 1932 | * the value of the character from the text that was mismatched. |
---|
| 1933 | */ |
---|
| 1934 | static void |
---|
| 1935 | computejumps(p, g) |
---|
| 1936 | struct parse *p; |
---|
| 1937 | struct re_guts *g; |
---|
| 1938 | { |
---|
| 1939 | int ch; |
---|
| 1940 | int mindex; |
---|
| 1941 | |
---|
| 1942 | /* Avoid making errors worse */ |
---|
| 1943 | if (p->error != 0) |
---|
| 1944 | return; |
---|
| 1945 | |
---|
| 1946 | g->charjump = (int*) malloc((NC + 1) * sizeof(int)); |
---|
| 1947 | if (g->charjump == NULL) /* Not a fatal error */ |
---|
| 1948 | return; |
---|
| 1949 | /* Adjust for signed chars, if necessary */ |
---|
| 1950 | g->charjump = &g->charjump[-(CHAR_MIN)]; |
---|
| 1951 | |
---|
| 1952 | /* If the character does not exist in the pattern, the jump |
---|
| 1953 | * is equal to the number of characters in the pattern. |
---|
| 1954 | */ |
---|
| 1955 | for (ch = CHAR_MIN; ch < (CHAR_MAX + 1); ch++) |
---|
| 1956 | g->charjump[ch] = g->mlen; |
---|
| 1957 | |
---|
| 1958 | /* If the character does exist, compute the jump that would |
---|
| 1959 | * take us to the last character in the pattern equal to it |
---|
| 1960 | * (notice that we match right to left, so that last character |
---|
| 1961 | * is the first one that would be matched). |
---|
| 1962 | */ |
---|
| 1963 | for (mindex = 0; mindex < g->mlen; mindex++) |
---|
| 1964 | g->charjump[(unsigned char) g->must[mindex]] = g->mlen - mindex - 1; |
---|
| 1965 | } |
---|
| 1966 | |
---|
| 1967 | /* |
---|
| 1968 | - computematchjumps - compute match jumps for BM scan |
---|
| 1969 | == static void computematchjumps(struct parse *p, struct re_guts *g); |
---|
| 1970 | * |
---|
| 1971 | * This algorithm assumes g->must exists and is has size greater than |
---|
| 1972 | * zero. It's based on the algorithm found on Computer Algorithms by |
---|
| 1973 | * Sara Baase. |
---|
| 1974 | * |
---|
| 1975 | * A match jump is the number of characters one needs to advance based |
---|
| 1976 | * on the already-matched suffix. |
---|
| 1977 | * Notice that all values here are minus (g->mlen-1), because of the way |
---|
| 1978 | * the search algorithm works. |
---|
| 1979 | */ |
---|
| 1980 | static void |
---|
| 1981 | computematchjumps(p, g) |
---|
| 1982 | struct parse *p; |
---|
| 1983 | struct re_guts *g; |
---|
| 1984 | { |
---|
| 1985 | int mindex; /* General "must" iterator */ |
---|
| 1986 | int suffix; /* Keeps track of matching suffix */ |
---|
| 1987 | int ssuffix; /* Keeps track of suffixes' suffix */ |
---|
| 1988 | int* pmatches; /* pmatches[k] points to the next i |
---|
| 1989 | * such that i+1...mlen is a substring |
---|
| 1990 | * of k+1...k+mlen-i-1 |
---|
| 1991 | */ |
---|
| 1992 | |
---|
| 1993 | /* Avoid making errors worse */ |
---|
| 1994 | if (p->error != 0) |
---|
| 1995 | return; |
---|
| 1996 | |
---|
| 1997 | pmatches = (int*) malloc(g->mlen * sizeof(unsigned int)); |
---|
| 1998 | if (pmatches == NULL) { |
---|
| 1999 | g->matchjump = NULL; |
---|
| 2000 | return; |
---|
| 2001 | } |
---|
| 2002 | |
---|
| 2003 | g->matchjump = (int*) malloc(g->mlen * sizeof(unsigned int)); |
---|
| 2004 | if (g->matchjump == NULL) /* Not a fatal error */ |
---|
| 2005 | return; |
---|
| 2006 | |
---|
| 2007 | /* Set maximum possible jump for each character in the pattern */ |
---|
| 2008 | for (mindex = 0; mindex < g->mlen; mindex++) |
---|
| 2009 | g->matchjump[mindex] = 2*g->mlen - mindex - 1; |
---|
| 2010 | |
---|
| 2011 | /* Compute pmatches[] */ |
---|
| 2012 | for (mindex = g->mlen - 1, suffix = g->mlen; mindex >= 0; |
---|
| 2013 | mindex--, suffix--) { |
---|
| 2014 | pmatches[mindex] = suffix; |
---|
| 2015 | |
---|
| 2016 | /* If a mismatch is found, interrupting the substring, |
---|
| 2017 | * compute the matchjump for that position. If no |
---|
| 2018 | * mismatch is found, then a text substring mismatched |
---|
| 2019 | * against the suffix will also mismatch against the |
---|
| 2020 | * substring. |
---|
| 2021 | */ |
---|
| 2022 | while (suffix < g->mlen |
---|
| 2023 | && g->must[mindex] != g->must[suffix]) { |
---|
| 2024 | g->matchjump[suffix] = MIN(g->matchjump[suffix], |
---|
| 2025 | g->mlen - mindex - 1); |
---|
| 2026 | suffix = pmatches[suffix]; |
---|
| 2027 | } |
---|
| 2028 | } |
---|
| 2029 | |
---|
| 2030 | /* Compute the matchjump up to the last substring found to jump |
---|
| 2031 | * to the beginning of the largest must pattern prefix matching |
---|
| 2032 | * it's own suffix. |
---|
| 2033 | */ |
---|
| 2034 | for (mindex = 0; mindex <= suffix; mindex++) |
---|
| 2035 | g->matchjump[mindex] = MIN(g->matchjump[mindex], |
---|
| 2036 | g->mlen + suffix - mindex); |
---|
| 2037 | |
---|
| 2038 | ssuffix = pmatches[suffix]; |
---|
| 2039 | while (suffix < g->mlen) { |
---|
| 2040 | while (suffix <= ssuffix && suffix < g->mlen) { |
---|
| 2041 | g->matchjump[suffix] = MIN(g->matchjump[suffix], |
---|
| 2042 | g->mlen + ssuffix - suffix); |
---|
| 2043 | suffix++; |
---|
| 2044 | } |
---|
| 2045 | if (suffix < g->mlen) |
---|
| 2046 | ssuffix = pmatches[ssuffix]; |
---|
| 2047 | } |
---|
| 2048 | |
---|
| 2049 | free(pmatches); |
---|
| 2050 | } |
---|
| 2051 | |
---|
| 2052 | /* |
---|
| 2053 | - pluscount - count + nesting |
---|
| 2054 | == static sopno pluscount(struct parse *p, struct re_guts *g); |
---|
| 2055 | */ |
---|
| 2056 | static sopno /* nesting depth */ |
---|
| 2057 | pluscount(p, g) |
---|
| 2058 | struct parse *p; |
---|
| 2059 | struct re_guts *g; |
---|
| 2060 | { |
---|
| 2061 | sop *scan; |
---|
| 2062 | sop s; |
---|
| 2063 | sopno plusnest = 0; |
---|
| 2064 | sopno maxnest = 0; |
---|
| 2065 | |
---|
| 2066 | if (p->error != 0) |
---|
| 2067 | return(0); /* there may not be an OEND */ |
---|
| 2068 | |
---|
| 2069 | scan = g->strip + 1; |
---|
| 2070 | do { |
---|
| 2071 | s = *scan++; |
---|
| 2072 | switch (OP(s)) { |
---|
| 2073 | case OPLUS_: |
---|
| 2074 | plusnest++; |
---|
| 2075 | break; |
---|
| 2076 | case O_PLUS: |
---|
| 2077 | if (plusnest > maxnest) |
---|
| 2078 | maxnest = plusnest; |
---|
| 2079 | plusnest--; |
---|
| 2080 | break; |
---|
| 2081 | } |
---|
| 2082 | } while (OP(s) != OEND); |
---|
| 2083 | if (plusnest != 0) |
---|
| 2084 | g->iflags |= BAD; |
---|
| 2085 | return(maxnest); |
---|
| 2086 | } |
---|
| 2087 | |
---|
| 2088 | #endif /* !_NO_REGEX */ |
---|