[352] | 1 | /*
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| 2 | regexec.c - TRE POSIX compatible matching functions (and more).
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| 3 |
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| 4 | Copyright (c) 2001-2009 Ville Laurikari <vl@iki.fi>
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| 5 | All rights reserved.
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| 6 |
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| 7 | Redistribution and use in source and binary forms, with or without
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| 8 | modification, are permitted provided that the following conditions
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| 9 | are met:
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| 10 |
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| 11 | 1. Redistributions of source code must retain the above copyright
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| 12 | notice, this list of conditions and the following disclaimer.
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| 13 |
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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 |
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| 18 | THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER AND CONTRIBUTORS
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| 19 | ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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| 20 | LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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| 21 | A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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| 22 | HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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| 23 | SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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| 24 | LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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| 25 | DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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| 26 | THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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| 27 | (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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| 28 | OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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| 29 |
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| 30 | */
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| 31 |
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| 32 | #include <stdlib.h>
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| 33 | #include <string.h>
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| 34 | #include <wchar.h>
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| 35 | #include <wctype.h>
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| 36 | #include <limits.h>
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| 37 | #include <stdint.h>
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| 38 |
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| 39 | #include <regex.h>
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| 40 |
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| 41 | #include "tre.h"
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| 42 |
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| 43 | #include <assert.h>
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| 44 |
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| 45 | static void
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| 46 | tre_fill_pmatch(size_t nmatch, regmatch_t pmatch[], int cflags,
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| 47 | const tre_tnfa_t *tnfa, regoff_t *tags, regoff_t match_eo);
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| 48 |
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| 49 | /***********************************************************************
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| 50 | from tre-match-utils.h
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| 51 | ***********************************************************************/
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| 52 |
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| 53 | #define GET_NEXT_WCHAR() do { \
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| 54 | prev_c = next_c; pos += pos_add_next; \
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| 55 | if ((pos_add_next = mbtowc(&next_c, str_byte, MB_LEN_MAX)) <= 0) { \
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| 56 | if (pos_add_next < 0) { ret = REG_NOMATCH; goto error_exit; } \
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| 57 | else pos_add_next++; \
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| 58 | } \
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| 59 | str_byte += pos_add_next; \
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| 60 | } while (0)
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| 61 |
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| 62 | #define IS_WORD_CHAR(c) ((c) == L'_' || tre_isalnum(c))
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| 63 |
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| 64 | #define CHECK_ASSERTIONS(assertions) \
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| 65 | (((assertions & ASSERT_AT_BOL) \
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| 66 | && (pos > 0 || reg_notbol) \
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| 67 | && (prev_c != L'\n' || !reg_newline)) \
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| 68 | || ((assertions & ASSERT_AT_EOL) \
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| 69 | && (next_c != L'\0' || reg_noteol) \
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| 70 | && (next_c != L'\n' || !reg_newline)) \
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| 71 | || ((assertions & ASSERT_AT_BOW) \
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| 72 | && (IS_WORD_CHAR(prev_c) || !IS_WORD_CHAR(next_c))) \
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| 73 | || ((assertions & ASSERT_AT_EOW) \
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| 74 | && (!IS_WORD_CHAR(prev_c) || IS_WORD_CHAR(next_c))) \
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| 75 | || ((assertions & ASSERT_AT_WB) \
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| 76 | && (pos != 0 && next_c != L'\0' \
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| 77 | && IS_WORD_CHAR(prev_c) == IS_WORD_CHAR(next_c))) \
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| 78 | || ((assertions & ASSERT_AT_WB_NEG) \
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| 79 | && (pos == 0 || next_c == L'\0' \
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| 80 | || IS_WORD_CHAR(prev_c) != IS_WORD_CHAR(next_c))))
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| 81 |
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| 82 | #define CHECK_CHAR_CLASSES(trans_i, tnfa, eflags) \
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| 83 | (((trans_i->assertions & ASSERT_CHAR_CLASS) \
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| 84 | && !(tnfa->cflags & REG_ICASE) \
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| 85 | && !tre_isctype((tre_cint_t)prev_c, trans_i->u.class)) \
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| 86 | || ((trans_i->assertions & ASSERT_CHAR_CLASS) \
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| 87 | && (tnfa->cflags & REG_ICASE) \
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| 88 | && !tre_isctype(tre_tolower((tre_cint_t)prev_c),trans_i->u.class) \
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| 89 | && !tre_isctype(tre_toupper((tre_cint_t)prev_c),trans_i->u.class)) \
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| 90 | || ((trans_i->assertions & ASSERT_CHAR_CLASS_NEG) \
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| 91 | && tre_neg_char_classes_match(trans_i->neg_classes,(tre_cint_t)prev_c,\
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| 92 | tnfa->cflags & REG_ICASE)))
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| 93 |
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| 94 |
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| 95 |
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| 96 |
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| 97 | /* Returns 1 if `t1' wins `t2', 0 otherwise. */
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| 98 | static int
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| 99 | tre_tag_order(int num_tags, tre_tag_direction_t *tag_directions,
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| 100 | regoff_t *t1, regoff_t *t2)
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| 101 | {
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| 102 | int i;
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| 103 | for (i = 0; i < num_tags; i++)
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| 104 | {
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| 105 | if (tag_directions[i] == TRE_TAG_MINIMIZE)
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| 106 | {
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| 107 | if (t1[i] < t2[i])
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| 108 | return 1;
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| 109 | if (t1[i] > t2[i])
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| 110 | return 0;
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| 111 | }
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| 112 | else
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| 113 | {
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| 114 | if (t1[i] > t2[i])
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| 115 | return 1;
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| 116 | if (t1[i] < t2[i])
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| 117 | return 0;
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| 118 | }
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| 119 | }
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| 120 | /* assert(0);*/
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| 121 | return 0;
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| 122 | }
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| 123 |
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| 124 | static int
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| 125 | tre_neg_char_classes_match(tre_ctype_t *classes, tre_cint_t wc, int icase)
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| 126 | {
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| 127 | while (*classes != (tre_ctype_t)0)
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| 128 | if ((!icase && tre_isctype(wc, *classes))
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| 129 | || (icase && (tre_isctype(tre_toupper(wc), *classes)
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| 130 | || tre_isctype(tre_tolower(wc), *classes))))
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| 131 | return 1; /* Match. */
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| 132 | else
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| 133 | classes++;
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| 134 | return 0; /* No match. */
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| 135 | }
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| 136 |
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| 137 |
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| 138 | /***********************************************************************
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| 139 | from tre-match-parallel.c
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| 140 | ***********************************************************************/
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| 141 |
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| 142 | /*
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| 143 | This algorithm searches for matches basically by reading characters
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| 144 | in the searched string one by one, starting at the beginning. All
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| 145 | matching paths in the TNFA are traversed in parallel. When two or
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| 146 | more paths reach the same state, exactly one is chosen according to
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| 147 | tag ordering rules; if returning submatches is not required it does
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| 148 | not matter which path is chosen.
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| 149 |
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| 150 | The worst case time required for finding the leftmost and longest
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| 151 | match, or determining that there is no match, is always linearly
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| 152 | dependent on the length of the text being searched.
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| 153 |
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| 154 | This algorithm cannot handle TNFAs with back referencing nodes.
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| 155 | See `tre-match-backtrack.c'.
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| 156 | */
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| 157 |
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| 158 | typedef struct {
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| 159 | tre_tnfa_transition_t *state;
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| 160 | regoff_t *tags;
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| 161 | } tre_tnfa_reach_t;
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| 162 |
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| 163 | typedef struct {
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| 164 | regoff_t pos;
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| 165 | regoff_t **tags;
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| 166 | } tre_reach_pos_t;
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| 167 |
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| 168 |
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| 169 | static reg_errcode_t
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| 170 | tre_tnfa_run_parallel(const tre_tnfa_t *tnfa, const void *string,
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| 171 | regoff_t *match_tags, int eflags,
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| 172 | regoff_t *match_end_ofs)
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| 173 | {
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| 174 | /* State variables required by GET_NEXT_WCHAR. */
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| 175 | tre_char_t prev_c = 0, next_c = 0;
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| 176 | const char *str_byte = string;
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| 177 | regoff_t pos = -1;
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| 178 | regoff_t pos_add_next = 1;
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| 179 | #ifdef TRE_MBSTATE
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| 180 | mbstate_t mbstate;
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| 181 | #endif /* TRE_MBSTATE */
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| 182 | int reg_notbol = eflags & REG_NOTBOL;
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| 183 | int reg_noteol = eflags & REG_NOTEOL;
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| 184 | int reg_newline = tnfa->cflags & REG_NEWLINE;
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| 185 | reg_errcode_t ret;
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| 186 |
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| 187 | char *buf;
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| 188 | tre_tnfa_transition_t *trans_i;
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| 189 | tre_tnfa_reach_t *reach, *reach_next, *reach_i, *reach_next_i;
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| 190 | tre_reach_pos_t *reach_pos;
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| 191 | int *tag_i;
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| 192 | int num_tags, i;
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| 193 |
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| 194 | regoff_t match_eo = -1; /* end offset of match (-1 if no match found yet) */
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| 195 | int new_match = 0;
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| 196 | regoff_t *tmp_tags = NULL;
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| 197 | regoff_t *tmp_iptr;
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| 198 |
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| 199 | #ifdef TRE_MBSTATE
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| 200 | memset(&mbstate, '\0', sizeof(mbstate));
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| 201 | #endif /* TRE_MBSTATE */
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| 202 |
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| 203 | if (!match_tags)
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| 204 | num_tags = 0;
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| 205 | else
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| 206 | num_tags = tnfa->num_tags;
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| 207 |
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| 208 | /* Allocate memory for temporary data required for matching. This needs to
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| 209 | be done for every matching operation to be thread safe. This allocates
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| 210 | everything in a single large block with calloc(). */
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| 211 | {
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| 212 | size_t tbytes, rbytes, pbytes, xbytes, total_bytes;
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| 213 | char *tmp_buf;
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| 214 |
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| 215 | /* Ensure that tbytes and xbytes*num_states cannot overflow, and that
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| 216 | * they don't contribute more than 1/8 of SIZE_MAX to total_bytes. */
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| 217 | if (num_tags > SIZE_MAX/(8 * sizeof(regoff_t) * tnfa->num_states))
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| 218 | return REG_ESPACE;
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| 219 |
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| 220 | /* Likewise check rbytes. */
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| 221 | if (tnfa->num_states+1 > SIZE_MAX/(8 * sizeof(*reach_next)))
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| 222 | return REG_ESPACE;
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| 223 |
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| 224 | /* Likewise check pbytes. */
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| 225 | if (tnfa->num_states > SIZE_MAX/(8 * sizeof(*reach_pos)))
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| 226 | return REG_ESPACE;
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| 227 |
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| 228 | /* Compute the length of the block we need. */
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| 229 | tbytes = sizeof(*tmp_tags) * num_tags;
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| 230 | rbytes = sizeof(*reach_next) * (tnfa->num_states + 1);
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| 231 | pbytes = sizeof(*reach_pos) * tnfa->num_states;
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| 232 | xbytes = sizeof(regoff_t) * num_tags;
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| 233 | total_bytes =
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| 234 | (sizeof(long) - 1) * 4 /* for alignment paddings */
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| 235 | + (rbytes + xbytes * tnfa->num_states) * 2 + tbytes + pbytes;
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| 236 |
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| 237 | /* Allocate the memory. */
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| 238 | buf = calloc(total_bytes, 1);
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| 239 | if (buf == NULL)
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| 240 | return REG_ESPACE;
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| 241 |
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| 242 | /* Get the various pointers within tmp_buf (properly aligned). */
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| 243 | tmp_tags = (void *)buf;
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| 244 | tmp_buf = buf + tbytes;
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| 245 | tmp_buf += ALIGN(tmp_buf, long);
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| 246 | reach_next = (void *)tmp_buf;
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| 247 | tmp_buf += rbytes;
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| 248 | tmp_buf += ALIGN(tmp_buf, long);
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| 249 | reach = (void *)tmp_buf;
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| 250 | tmp_buf += rbytes;
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| 251 | tmp_buf += ALIGN(tmp_buf, long);
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| 252 | reach_pos = (void *)tmp_buf;
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| 253 | tmp_buf += pbytes;
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| 254 | tmp_buf += ALIGN(tmp_buf, long);
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| 255 | for (i = 0; i < tnfa->num_states; i++)
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| 256 | {
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| 257 | reach[i].tags = (void *)tmp_buf;
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| 258 | tmp_buf += xbytes;
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| 259 | reach_next[i].tags = (void *)tmp_buf;
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| 260 | tmp_buf += xbytes;
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| 261 | }
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| 262 | }
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| 263 |
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| 264 | for (i = 0; i < tnfa->num_states; i++)
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| 265 | reach_pos[i].pos = -1;
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| 266 |
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| 267 | GET_NEXT_WCHAR();
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| 268 | pos = 0;
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| 269 |
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| 270 | reach_next_i = reach_next;
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| 271 | while (1)
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| 272 | {
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| 273 | /* If no match found yet, add the initial states to `reach_next'. */
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| 274 | if (match_eo < 0)
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| 275 | {
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| 276 | trans_i = tnfa->initial;
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| 277 | while (trans_i->state != NULL)
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| 278 | {
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| 279 | if (reach_pos[trans_i->state_id].pos < pos)
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| 280 | {
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| 281 | if (trans_i->assertions
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| 282 | && CHECK_ASSERTIONS(trans_i->assertions))
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| 283 | {
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| 284 | trans_i++;
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| 285 | continue;
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| 286 | }
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| 287 |
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| 288 | reach_next_i->state = trans_i->state;
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| 289 | for (i = 0; i < num_tags; i++)
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| 290 | reach_next_i->tags[i] = -1;
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| 291 | tag_i = trans_i->tags;
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| 292 | if (tag_i)
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| 293 | while (*tag_i >= 0)
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| 294 | {
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| 295 | if (*tag_i < num_tags)
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| 296 | reach_next_i->tags[*tag_i] = pos;
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| 297 | tag_i++;
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| 298 | }
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| 299 | if (reach_next_i->state == tnfa->final)
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| 300 | {
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| 301 | match_eo = pos;
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| 302 | new_match = 1;
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| 303 | for (i = 0; i < num_tags; i++)
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| 304 | match_tags[i] = reach_next_i->tags[i];
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| 305 | }
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| 306 | reach_pos[trans_i->state_id].pos = pos;
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| 307 | reach_pos[trans_i->state_id].tags = &reach_next_i->tags;
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| 308 | reach_next_i++;
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| 309 | }
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| 310 | trans_i++;
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| 311 | }
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| 312 | reach_next_i->state = NULL;
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| 313 | }
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| 314 | else
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| 315 | {
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| 316 | if (num_tags == 0 || reach_next_i == reach_next)
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| 317 | /* We have found a match. */
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| 318 | break;
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| 319 | }
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| 320 |
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| 321 | /* Check for end of string. */
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| 322 | if (!next_c) break;
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| 323 |
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| 324 | GET_NEXT_WCHAR();
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| 325 |
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| 326 | /* Swap `reach' and `reach_next'. */
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| 327 | reach_i = reach;
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| 328 | reach = reach_next;
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| 329 | reach_next = reach_i;
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| 330 |
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| 331 | /* For each state in `reach', weed out states that don't fulfill the
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| 332 | minimal matching conditions. */
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| 333 | if (tnfa->num_minimals && new_match)
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| 334 | {
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| 335 | new_match = 0;
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| 336 | reach_next_i = reach_next;
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| 337 | for (reach_i = reach; reach_i->state; reach_i++)
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| 338 | {
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| 339 | int skip = 0;
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| 340 | for (i = 0; tnfa->minimal_tags[i] >= 0; i += 2)
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| 341 | {
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| 342 | int end = tnfa->minimal_tags[i];
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| 343 | int start = tnfa->minimal_tags[i + 1];
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| 344 | if (end >= num_tags)
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| 345 | {
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| 346 | skip = 1;
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| 347 | break;
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| 348 | }
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| 349 | else if (reach_i->tags[start] == match_tags[start]
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| 350 | && reach_i->tags[end] < match_tags[end])
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| 351 | {
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| 352 | skip = 1;
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| 353 | break;
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| 354 | }
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| 355 | }
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| 356 | if (!skip)
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| 357 | {
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| 358 | reach_next_i->state = reach_i->state;
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| 359 | tmp_iptr = reach_next_i->tags;
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| 360 | reach_next_i->tags = reach_i->tags;
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| 361 | reach_i->tags = tmp_iptr;
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| 362 | reach_next_i++;
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| 363 | }
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| 364 | }
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| 365 | reach_next_i->state = NULL;
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| 366 |
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| 367 | /* Swap `reach' and `reach_next'. */
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| 368 | reach_i = reach;
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| 369 | reach = reach_next;
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| 370 | reach_next = reach_i;
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| 371 | }
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| 372 |
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| 373 | /* For each state in `reach' see if there is a transition leaving with
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| 374 | the current input symbol to a state not yet in `reach_next', and
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| 375 | add the destination states to `reach_next'. */
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| 376 | reach_next_i = reach_next;
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| 377 | for (reach_i = reach; reach_i->state; reach_i++)
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| 378 | {
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| 379 | for (trans_i = reach_i->state; trans_i->state; trans_i++)
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| 380 | {
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| 381 | /* Does this transition match the input symbol? */
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| 382 | if (trans_i->code_min <= (tre_cint_t)prev_c &&
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| 383 | trans_i->code_max >= (tre_cint_t)prev_c)
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| 384 | {
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| 385 | if (trans_i->assertions
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| 386 | && (CHECK_ASSERTIONS(trans_i->assertions)
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| 387 | || CHECK_CHAR_CLASSES(trans_i, tnfa, eflags)))
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| 388 | {
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| 389 | continue;
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| 390 | }
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| 391 |
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| 392 | /* Compute the tags after this transition. */
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| 393 | for (i = 0; i < num_tags; i++)
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| 394 | tmp_tags[i] = reach_i->tags[i];
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| 395 | tag_i = trans_i->tags;
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| 396 | if (tag_i != NULL)
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| 397 | while (*tag_i >= 0)
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| 398 | {
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| 399 | if (*tag_i < num_tags)
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| 400 | tmp_tags[*tag_i] = pos;
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| 401 | tag_i++;
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| 402 | }
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| 403 |
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| 404 | if (reach_pos[trans_i->state_id].pos < pos)
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| 405 | {
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| 406 | /* Found an unvisited node. */
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| 407 | reach_next_i->state = trans_i->state;
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| 408 | tmp_iptr = reach_next_i->tags;
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| 409 | reach_next_i->tags = tmp_tags;
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| 410 | tmp_tags = tmp_iptr;
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| 411 | reach_pos[trans_i->state_id].pos = pos;
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| 412 | reach_pos[trans_i->state_id].tags = &reach_next_i->tags;
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| 413 |
|
---|
| 414 | if (reach_next_i->state == tnfa->final
|
---|
| 415 | && (match_eo == -1
|
---|
| 416 | || (num_tags > 0
|
---|
| 417 | && reach_next_i->tags[0] <= match_tags[0])))
|
---|
| 418 | {
|
---|
| 419 | match_eo = pos;
|
---|
| 420 | new_match = 1;
|
---|
| 421 | for (i = 0; i < num_tags; i++)
|
---|
| 422 | match_tags[i] = reach_next_i->tags[i];
|
---|
| 423 | }
|
---|
| 424 | reach_next_i++;
|
---|
| 425 |
|
---|
| 426 | }
|
---|
| 427 | else
|
---|
| 428 | {
|
---|
| 429 | assert(reach_pos[trans_i->state_id].pos == pos);
|
---|
| 430 | /* Another path has also reached this state. We choose
|
---|
| 431 | the winner by examining the tag values for both
|
---|
| 432 | paths. */
|
---|
| 433 | if (tre_tag_order(num_tags, tnfa->tag_directions,
|
---|
| 434 | tmp_tags,
|
---|
| 435 | *reach_pos[trans_i->state_id].tags))
|
---|
| 436 | {
|
---|
| 437 | /* The new path wins. */
|
---|
| 438 | tmp_iptr = *reach_pos[trans_i->state_id].tags;
|
---|
| 439 | *reach_pos[trans_i->state_id].tags = tmp_tags;
|
---|
| 440 | if (trans_i->state == tnfa->final)
|
---|
| 441 | {
|
---|
| 442 | match_eo = pos;
|
---|
| 443 | new_match = 1;
|
---|
| 444 | for (i = 0; i < num_tags; i++)
|
---|
| 445 | match_tags[i] = tmp_tags[i];
|
---|
| 446 | }
|
---|
| 447 | tmp_tags = tmp_iptr;
|
---|
| 448 | }
|
---|
| 449 | }
|
---|
| 450 | }
|
---|
| 451 | }
|
---|
| 452 | }
|
---|
| 453 | reach_next_i->state = NULL;
|
---|
| 454 | }
|
---|
| 455 |
|
---|
| 456 | *match_end_ofs = match_eo;
|
---|
| 457 | ret = match_eo >= 0 ? REG_OK : REG_NOMATCH;
|
---|
| 458 | error_exit:
|
---|
| 459 | xfree(buf);
|
---|
| 460 | return ret;
|
---|
| 461 | }
|
---|
| 462 |
|
---|
| 463 |
|
---|
| 464 |
|
---|
| 465 | /***********************************************************************
|
---|
| 466 | from tre-match-backtrack.c
|
---|
| 467 | ***********************************************************************/
|
---|
| 468 |
|
---|
| 469 | /*
|
---|
| 470 | This matcher is for regexps that use back referencing. Regexp matching
|
---|
| 471 | with back referencing is an NP-complete problem on the number of back
|
---|
| 472 | references. The easiest way to match them is to use a backtracking
|
---|
| 473 | routine which basically goes through all possible paths in the TNFA
|
---|
| 474 | and chooses the one which results in the best (leftmost and longest)
|
---|
| 475 | match. This can be spectacularly expensive and may run out of stack
|
---|
| 476 | space, but there really is no better known generic algorithm. Quoting
|
---|
| 477 | Henry Spencer from comp.compilers:
|
---|
| 478 | <URL: http://compilers.iecc.com/comparch/article/93-03-102>
|
---|
| 479 |
|
---|
| 480 | POSIX.2 REs require longest match, which is really exciting to
|
---|
| 481 | implement since the obsolete ("basic") variant also includes
|
---|
| 482 | \<digit>. I haven't found a better way of tackling this than doing
|
---|
| 483 | a preliminary match using a DFA (or simulation) on a modified RE
|
---|
| 484 | that just replicates subREs for \<digit>, and then doing a
|
---|
| 485 | backtracking match to determine whether the subRE matches were
|
---|
| 486 | right. This can be rather slow, but I console myself with the
|
---|
| 487 | thought that people who use \<digit> deserve very slow execution.
|
---|
| 488 | (Pun unintentional but very appropriate.)
|
---|
| 489 |
|
---|
| 490 | */
|
---|
| 491 |
|
---|
| 492 | typedef struct {
|
---|
| 493 | regoff_t pos;
|
---|
| 494 | const char *str_byte;
|
---|
| 495 | tre_tnfa_transition_t *state;
|
---|
| 496 | int state_id;
|
---|
| 497 | int next_c;
|
---|
| 498 | regoff_t *tags;
|
---|
| 499 | #ifdef TRE_MBSTATE
|
---|
| 500 | mbstate_t mbstate;
|
---|
| 501 | #endif /* TRE_MBSTATE */
|
---|
| 502 | } tre_backtrack_item_t;
|
---|
| 503 |
|
---|
| 504 | typedef struct tre_backtrack_struct {
|
---|
| 505 | tre_backtrack_item_t item;
|
---|
| 506 | struct tre_backtrack_struct *prev;
|
---|
| 507 | struct tre_backtrack_struct *next;
|
---|
| 508 | } *tre_backtrack_t;
|
---|
| 509 |
|
---|
| 510 | #ifdef TRE_MBSTATE
|
---|
| 511 | #define BT_STACK_MBSTATE_IN stack->item.mbstate = (mbstate)
|
---|
| 512 | #define BT_STACK_MBSTATE_OUT (mbstate) = stack->item.mbstate
|
---|
| 513 | #else /* !TRE_MBSTATE */
|
---|
| 514 | #define BT_STACK_MBSTATE_IN
|
---|
| 515 | #define BT_STACK_MBSTATE_OUT
|
---|
| 516 | #endif /* !TRE_MBSTATE */
|
---|
| 517 |
|
---|
| 518 | #define tre_bt_mem_new tre_mem_new
|
---|
| 519 | #define tre_bt_mem_alloc tre_mem_alloc
|
---|
| 520 | #define tre_bt_mem_destroy tre_mem_destroy
|
---|
| 521 |
|
---|
| 522 |
|
---|
| 523 | #define BT_STACK_PUSH(_pos, _str_byte, _str_wide, _state, _state_id, _next_c, _tags, _mbstate) \
|
---|
| 524 | do \
|
---|
| 525 | { \
|
---|
| 526 | int i; \
|
---|
| 527 | if (!stack->next) \
|
---|
| 528 | { \
|
---|
| 529 | tre_backtrack_t s; \
|
---|
| 530 | s = tre_bt_mem_alloc(mem, sizeof(*s)); \
|
---|
| 531 | if (!s) \
|
---|
| 532 | { \
|
---|
| 533 | tre_bt_mem_destroy(mem); \
|
---|
| 534 | if (tags) \
|
---|
| 535 | xfree(tags); \
|
---|
| 536 | if (pmatch) \
|
---|
| 537 | xfree(pmatch); \
|
---|
| 538 | if (states_seen) \
|
---|
| 539 | xfree(states_seen); \
|
---|
| 540 | return REG_ESPACE; \
|
---|
| 541 | } \
|
---|
| 542 | s->prev = stack; \
|
---|
| 543 | s->next = NULL; \
|
---|
| 544 | s->item.tags = tre_bt_mem_alloc(mem, \
|
---|
| 545 | sizeof(*tags) * tnfa->num_tags); \
|
---|
| 546 | if (!s->item.tags) \
|
---|
| 547 | { \
|
---|
| 548 | tre_bt_mem_destroy(mem); \
|
---|
| 549 | if (tags) \
|
---|
| 550 | xfree(tags); \
|
---|
| 551 | if (pmatch) \
|
---|
| 552 | xfree(pmatch); \
|
---|
| 553 | if (states_seen) \
|
---|
| 554 | xfree(states_seen); \
|
---|
| 555 | return REG_ESPACE; \
|
---|
| 556 | } \
|
---|
| 557 | stack->next = s; \
|
---|
| 558 | stack = s; \
|
---|
| 559 | } \
|
---|
| 560 | else \
|
---|
| 561 | stack = stack->next; \
|
---|
| 562 | stack->item.pos = (_pos); \
|
---|
| 563 | stack->item.str_byte = (_str_byte); \
|
---|
| 564 | stack->item.state = (_state); \
|
---|
| 565 | stack->item.state_id = (_state_id); \
|
---|
| 566 | stack->item.next_c = (_next_c); \
|
---|
| 567 | for (i = 0; i < tnfa->num_tags; i++) \
|
---|
| 568 | stack->item.tags[i] = (_tags)[i]; \
|
---|
| 569 | BT_STACK_MBSTATE_IN; \
|
---|
| 570 | } \
|
---|
| 571 | while (0)
|
---|
| 572 |
|
---|
| 573 | #define BT_STACK_POP() \
|
---|
| 574 | do \
|
---|
| 575 | { \
|
---|
| 576 | int i; \
|
---|
| 577 | assert(stack->prev); \
|
---|
| 578 | pos = stack->item.pos; \
|
---|
| 579 | str_byte = stack->item.str_byte; \
|
---|
| 580 | state = stack->item.state; \
|
---|
| 581 | next_c = stack->item.next_c; \
|
---|
| 582 | for (i = 0; i < tnfa->num_tags; i++) \
|
---|
| 583 | tags[i] = stack->item.tags[i]; \
|
---|
| 584 | BT_STACK_MBSTATE_OUT; \
|
---|
| 585 | stack = stack->prev; \
|
---|
| 586 | } \
|
---|
| 587 | while (0)
|
---|
| 588 |
|
---|
| 589 | #undef MIN
|
---|
| 590 | #define MIN(a, b) ((a) <= (b) ? (a) : (b))
|
---|
| 591 |
|
---|
| 592 | static reg_errcode_t
|
---|
| 593 | tre_tnfa_run_backtrack(const tre_tnfa_t *tnfa, const void *string,
|
---|
| 594 | regoff_t *match_tags, int eflags, regoff_t *match_end_ofs)
|
---|
| 595 | {
|
---|
| 596 | /* State variables required by GET_NEXT_WCHAR. */
|
---|
| 597 | tre_char_t prev_c = 0, next_c = 0;
|
---|
| 598 | const char *str_byte = string;
|
---|
| 599 | regoff_t pos = 0;
|
---|
| 600 | regoff_t pos_add_next = 1;
|
---|
| 601 | #ifdef TRE_MBSTATE
|
---|
| 602 | mbstate_t mbstate;
|
---|
| 603 | #endif /* TRE_MBSTATE */
|
---|
| 604 | int reg_notbol = eflags & REG_NOTBOL;
|
---|
| 605 | int reg_noteol = eflags & REG_NOTEOL;
|
---|
| 606 | int reg_newline = tnfa->cflags & REG_NEWLINE;
|
---|
| 607 |
|
---|
| 608 | /* These are used to remember the necessary values of the above
|
---|
| 609 | variables to return to the position where the current search
|
---|
| 610 | started from. */
|
---|
| 611 | int next_c_start;
|
---|
| 612 | const char *str_byte_start;
|
---|
| 613 | regoff_t pos_start = -1;
|
---|
| 614 | #ifdef TRE_MBSTATE
|
---|
| 615 | mbstate_t mbstate_start;
|
---|
| 616 | #endif /* TRE_MBSTATE */
|
---|
| 617 |
|
---|
| 618 | /* End offset of best match so far, or -1 if no match found yet. */
|
---|
| 619 | regoff_t match_eo = -1;
|
---|
| 620 | /* Tag arrays. */
|
---|
| 621 | int *next_tags;
|
---|
| 622 | regoff_t *tags = NULL;
|
---|
| 623 | /* Current TNFA state. */
|
---|
| 624 | tre_tnfa_transition_t *state;
|
---|
| 625 | int *states_seen = NULL;
|
---|
| 626 |
|
---|
| 627 | /* Memory allocator to for allocating the backtracking stack. */
|
---|
| 628 | tre_mem_t mem = tre_bt_mem_new();
|
---|
| 629 |
|
---|
| 630 | /* The backtracking stack. */
|
---|
| 631 | tre_backtrack_t stack;
|
---|
| 632 |
|
---|
| 633 | tre_tnfa_transition_t *trans_i;
|
---|
| 634 | regmatch_t *pmatch = NULL;
|
---|
| 635 | int ret;
|
---|
| 636 |
|
---|
| 637 | #ifdef TRE_MBSTATE
|
---|
| 638 | memset(&mbstate, '\0', sizeof(mbstate));
|
---|
| 639 | #endif /* TRE_MBSTATE */
|
---|
| 640 |
|
---|
| 641 | if (!mem)
|
---|
| 642 | return REG_ESPACE;
|
---|
| 643 | stack = tre_bt_mem_alloc(mem, sizeof(*stack));
|
---|
| 644 | if (!stack)
|
---|
| 645 | {
|
---|
| 646 | ret = REG_ESPACE;
|
---|
| 647 | goto error_exit;
|
---|
| 648 | }
|
---|
| 649 | stack->prev = NULL;
|
---|
| 650 | stack->next = NULL;
|
---|
| 651 |
|
---|
| 652 | if (tnfa->num_tags)
|
---|
| 653 | {
|
---|
| 654 | tags = xmalloc(sizeof(*tags) * tnfa->num_tags);
|
---|
| 655 | if (!tags)
|
---|
| 656 | {
|
---|
| 657 | ret = REG_ESPACE;
|
---|
| 658 | goto error_exit;
|
---|
| 659 | }
|
---|
| 660 | }
|
---|
| 661 | if (tnfa->num_submatches)
|
---|
| 662 | {
|
---|
| 663 | pmatch = xmalloc(sizeof(*pmatch) * tnfa->num_submatches);
|
---|
| 664 | if (!pmatch)
|
---|
| 665 | {
|
---|
| 666 | ret = REG_ESPACE;
|
---|
| 667 | goto error_exit;
|
---|
| 668 | }
|
---|
| 669 | }
|
---|
| 670 | if (tnfa->num_states)
|
---|
| 671 | {
|
---|
| 672 | states_seen = xmalloc(sizeof(*states_seen) * tnfa->num_states);
|
---|
| 673 | if (!states_seen)
|
---|
| 674 | {
|
---|
| 675 | ret = REG_ESPACE;
|
---|
| 676 | goto error_exit;
|
---|
| 677 | }
|
---|
| 678 | }
|
---|
| 679 |
|
---|
| 680 | retry:
|
---|
| 681 | {
|
---|
| 682 | int i;
|
---|
| 683 | for (i = 0; i < tnfa->num_tags; i++)
|
---|
| 684 | {
|
---|
| 685 | tags[i] = -1;
|
---|
| 686 | if (match_tags)
|
---|
| 687 | match_tags[i] = -1;
|
---|
| 688 | }
|
---|
| 689 | for (i = 0; i < tnfa->num_states; i++)
|
---|
| 690 | states_seen[i] = 0;
|
---|
| 691 | }
|
---|
| 692 |
|
---|
| 693 | state = NULL;
|
---|
| 694 | pos = pos_start;
|
---|
| 695 | GET_NEXT_WCHAR();
|
---|
| 696 | pos_start = pos;
|
---|
| 697 | next_c_start = next_c;
|
---|
| 698 | str_byte_start = str_byte;
|
---|
| 699 | #ifdef TRE_MBSTATE
|
---|
| 700 | mbstate_start = mbstate;
|
---|
| 701 | #endif /* TRE_MBSTATE */
|
---|
| 702 |
|
---|
| 703 | /* Handle initial states. */
|
---|
| 704 | next_tags = NULL;
|
---|
| 705 | for (trans_i = tnfa->initial; trans_i->state; trans_i++)
|
---|
| 706 | {
|
---|
| 707 | if (trans_i->assertions && CHECK_ASSERTIONS(trans_i->assertions))
|
---|
| 708 | {
|
---|
| 709 | continue;
|
---|
| 710 | }
|
---|
| 711 | if (state == NULL)
|
---|
| 712 | {
|
---|
| 713 | /* Start from this state. */
|
---|
| 714 | state = trans_i->state;
|
---|
| 715 | next_tags = trans_i->tags;
|
---|
| 716 | }
|
---|
| 717 | else
|
---|
| 718 | {
|
---|
| 719 | /* Backtrack to this state. */
|
---|
| 720 | BT_STACK_PUSH(pos, str_byte, 0, trans_i->state,
|
---|
| 721 | trans_i->state_id, next_c, tags, mbstate);
|
---|
| 722 | {
|
---|
| 723 | int *tmp = trans_i->tags;
|
---|
| 724 | if (tmp)
|
---|
| 725 | while (*tmp >= 0)
|
---|
| 726 | stack->item.tags[*tmp++] = pos;
|
---|
| 727 | }
|
---|
| 728 | }
|
---|
| 729 | }
|
---|
| 730 |
|
---|
| 731 | if (next_tags)
|
---|
| 732 | for (; *next_tags >= 0; next_tags++)
|
---|
| 733 | tags[*next_tags] = pos;
|
---|
| 734 |
|
---|
| 735 |
|
---|
| 736 | if (state == NULL)
|
---|
| 737 | goto backtrack;
|
---|
| 738 |
|
---|
| 739 | while (1)
|
---|
| 740 | {
|
---|
| 741 | tre_tnfa_transition_t *next_state;
|
---|
| 742 | int empty_br_match;
|
---|
| 743 |
|
---|
| 744 | if (state == tnfa->final)
|
---|
| 745 | {
|
---|
| 746 | if (match_eo < pos
|
---|
| 747 | || (match_eo == pos
|
---|
| 748 | && match_tags
|
---|
| 749 | && tre_tag_order(tnfa->num_tags, tnfa->tag_directions,
|
---|
| 750 | tags, match_tags)))
|
---|
| 751 | {
|
---|
| 752 | int i;
|
---|
| 753 | /* This match wins the previous match. */
|
---|
| 754 | match_eo = pos;
|
---|
| 755 | if (match_tags)
|
---|
| 756 | for (i = 0; i < tnfa->num_tags; i++)
|
---|
| 757 | match_tags[i] = tags[i];
|
---|
| 758 | }
|
---|
| 759 | /* Our TNFAs never have transitions leaving from the final state,
|
---|
| 760 | so we jump right to backtracking. */
|
---|
| 761 | goto backtrack;
|
---|
| 762 | }
|
---|
| 763 |
|
---|
| 764 | /* Go to the next character in the input string. */
|
---|
| 765 | empty_br_match = 0;
|
---|
| 766 | trans_i = state;
|
---|
| 767 | if (trans_i->state && trans_i->assertions & ASSERT_BACKREF)
|
---|
| 768 | {
|
---|
| 769 | /* This is a back reference state. All transitions leaving from
|
---|
| 770 | this state have the same back reference "assertion". Instead
|
---|
| 771 | of reading the next character, we match the back reference. */
|
---|
| 772 | regoff_t so, eo;
|
---|
| 773 | int bt = trans_i->u.backref;
|
---|
| 774 | regoff_t bt_len;
|
---|
| 775 | int result;
|
---|
| 776 |
|
---|
| 777 | /* Get the substring we need to match against. Remember to
|
---|
| 778 | turn off REG_NOSUB temporarily. */
|
---|
| 779 | tre_fill_pmatch(bt + 1, pmatch, tnfa->cflags & ~REG_NOSUB,
|
---|
| 780 | tnfa, tags, pos);
|
---|
| 781 | so = pmatch[bt].rm_so;
|
---|
| 782 | eo = pmatch[bt].rm_eo;
|
---|
| 783 | bt_len = eo - so;
|
---|
| 784 |
|
---|
| 785 | result = strncmp((const char*)string + so, str_byte - 1,
|
---|
| 786 | (size_t)bt_len);
|
---|
| 787 |
|
---|
| 788 | if (result == 0)
|
---|
| 789 | {
|
---|
| 790 | /* Back reference matched. Check for infinite loop. */
|
---|
| 791 | if (bt_len == 0)
|
---|
| 792 | empty_br_match = 1;
|
---|
| 793 | if (empty_br_match && states_seen[trans_i->state_id])
|
---|
| 794 | {
|
---|
| 795 | goto backtrack;
|
---|
| 796 | }
|
---|
| 797 |
|
---|
| 798 | states_seen[trans_i->state_id] = empty_br_match;
|
---|
| 799 |
|
---|
| 800 | /* Advance in input string and resync `prev_c', `next_c'
|
---|
| 801 | and pos. */
|
---|
| 802 | str_byte += bt_len - 1;
|
---|
| 803 | pos += bt_len - 1;
|
---|
| 804 | GET_NEXT_WCHAR();
|
---|
| 805 | }
|
---|
| 806 | else
|
---|
| 807 | {
|
---|
| 808 | goto backtrack;
|
---|
| 809 | }
|
---|
| 810 | }
|
---|
| 811 | else
|
---|
| 812 | {
|
---|
| 813 | /* Check for end of string. */
|
---|
| 814 | if (next_c == L'\0')
|
---|
| 815 | goto backtrack;
|
---|
| 816 |
|
---|
| 817 | /* Read the next character. */
|
---|
| 818 | GET_NEXT_WCHAR();
|
---|
| 819 | }
|
---|
| 820 |
|
---|
| 821 | next_state = NULL;
|
---|
| 822 | for (trans_i = state; trans_i->state; trans_i++)
|
---|
| 823 | {
|
---|
| 824 | if (trans_i->code_min <= (tre_cint_t)prev_c
|
---|
| 825 | && trans_i->code_max >= (tre_cint_t)prev_c)
|
---|
| 826 | {
|
---|
| 827 | if (trans_i->assertions
|
---|
| 828 | && (CHECK_ASSERTIONS(trans_i->assertions)
|
---|
| 829 | || CHECK_CHAR_CLASSES(trans_i, tnfa, eflags)))
|
---|
| 830 | {
|
---|
| 831 | continue;
|
---|
| 832 | }
|
---|
| 833 |
|
---|
| 834 | if (next_state == NULL)
|
---|
| 835 | {
|
---|
| 836 | /* First matching transition. */
|
---|
| 837 | next_state = trans_i->state;
|
---|
| 838 | next_tags = trans_i->tags;
|
---|
| 839 | }
|
---|
| 840 | else
|
---|
| 841 | {
|
---|
| 842 | /* Second matching transition. We may need to backtrack here
|
---|
| 843 | to take this transition instead of the first one, so we
|
---|
| 844 | push this transition in the backtracking stack so we can
|
---|
| 845 | jump back here if needed. */
|
---|
| 846 | BT_STACK_PUSH(pos, str_byte, 0, trans_i->state,
|
---|
| 847 | trans_i->state_id, next_c, tags, mbstate);
|
---|
| 848 | {
|
---|
| 849 | int *tmp;
|
---|
| 850 | for (tmp = trans_i->tags; tmp && *tmp >= 0; tmp++)
|
---|
| 851 | stack->item.tags[*tmp] = pos;
|
---|
| 852 | }
|
---|
| 853 | #if 0 /* XXX - it's important not to look at all transitions here to keep
|
---|
| 854 | the stack small! */
|
---|
| 855 | break;
|
---|
| 856 | #endif
|
---|
| 857 | }
|
---|
| 858 | }
|
---|
| 859 | }
|
---|
| 860 |
|
---|
| 861 | if (next_state != NULL)
|
---|
| 862 | {
|
---|
| 863 | /* Matching transitions were found. Take the first one. */
|
---|
| 864 | state = next_state;
|
---|
| 865 |
|
---|
| 866 | /* Update the tag values. */
|
---|
| 867 | if (next_tags)
|
---|
| 868 | while (*next_tags >= 0)
|
---|
| 869 | tags[*next_tags++] = pos;
|
---|
| 870 | }
|
---|
| 871 | else
|
---|
| 872 | {
|
---|
| 873 | backtrack:
|
---|
| 874 | /* A matching transition was not found. Try to backtrack. */
|
---|
| 875 | if (stack->prev)
|
---|
| 876 | {
|
---|
| 877 | if (stack->item.state->assertions & ASSERT_BACKREF)
|
---|
| 878 | {
|
---|
| 879 | states_seen[stack->item.state_id] = 0;
|
---|
| 880 | }
|
---|
| 881 |
|
---|
| 882 | BT_STACK_POP();
|
---|
| 883 | }
|
---|
| 884 | else if (match_eo < 0)
|
---|
| 885 | {
|
---|
| 886 | /* Try starting from a later position in the input string. */
|
---|
| 887 | /* Check for end of string. */
|
---|
| 888 | if (next_c == L'\0')
|
---|
| 889 | {
|
---|
| 890 | break;
|
---|
| 891 | }
|
---|
| 892 | next_c = next_c_start;
|
---|
| 893 | #ifdef TRE_MBSTATE
|
---|
| 894 | mbstate = mbstate_start;
|
---|
| 895 | #endif /* TRE_MBSTATE */
|
---|
| 896 | str_byte = str_byte_start;
|
---|
| 897 | goto retry;
|
---|
| 898 | }
|
---|
| 899 | else
|
---|
| 900 | {
|
---|
| 901 | break;
|
---|
| 902 | }
|
---|
| 903 | }
|
---|
| 904 | }
|
---|
| 905 |
|
---|
| 906 | ret = match_eo >= 0 ? REG_OK : REG_NOMATCH;
|
---|
| 907 | *match_end_ofs = match_eo;
|
---|
| 908 |
|
---|
| 909 | error_exit:
|
---|
| 910 | tre_bt_mem_destroy(mem);
|
---|
| 911 | #ifndef TRE_USE_ALLOCA
|
---|
| 912 | if (tags)
|
---|
| 913 | xfree(tags);
|
---|
| 914 | if (pmatch)
|
---|
| 915 | xfree(pmatch);
|
---|
| 916 | if (states_seen)
|
---|
| 917 | xfree(states_seen);
|
---|
| 918 | #endif /* !TRE_USE_ALLOCA */
|
---|
| 919 |
|
---|
| 920 | return ret;
|
---|
| 921 | }
|
---|
| 922 |
|
---|
| 923 | /***********************************************************************
|
---|
| 924 | from regexec.c
|
---|
| 925 | ***********************************************************************/
|
---|
| 926 |
|
---|
| 927 | /* Fills the POSIX.2 regmatch_t array according to the TNFA tag and match
|
---|
| 928 | endpoint values. */
|
---|
| 929 | static void
|
---|
| 930 | tre_fill_pmatch(size_t nmatch, regmatch_t pmatch[], int cflags,
|
---|
| 931 | const tre_tnfa_t *tnfa, regoff_t *tags, regoff_t match_eo)
|
---|
| 932 | {
|
---|
| 933 | tre_submatch_data_t *submatch_data;
|
---|
| 934 | unsigned int i, j;
|
---|
| 935 | int *parents;
|
---|
| 936 |
|
---|
| 937 | i = 0;
|
---|
| 938 | if (match_eo >= 0 && !(cflags & REG_NOSUB))
|
---|
| 939 | {
|
---|
| 940 | /* Construct submatch offsets from the tags. */
|
---|
| 941 | submatch_data = tnfa->submatch_data;
|
---|
| 942 | while (i < tnfa->num_submatches && i < nmatch)
|
---|
| 943 | {
|
---|
| 944 | if (submatch_data[i].so_tag == tnfa->end_tag)
|
---|
| 945 | pmatch[i].rm_so = match_eo;
|
---|
| 946 | else
|
---|
| 947 | pmatch[i].rm_so = tags[submatch_data[i].so_tag];
|
---|
| 948 |
|
---|
| 949 | if (submatch_data[i].eo_tag == tnfa->end_tag)
|
---|
| 950 | pmatch[i].rm_eo = match_eo;
|
---|
| 951 | else
|
---|
| 952 | pmatch[i].rm_eo = tags[submatch_data[i].eo_tag];
|
---|
| 953 |
|
---|
| 954 | /* If either of the endpoints were not used, this submatch
|
---|
| 955 | was not part of the match. */
|
---|
| 956 | if (pmatch[i].rm_so == -1 || pmatch[i].rm_eo == -1)
|
---|
| 957 | pmatch[i].rm_so = pmatch[i].rm_eo = -1;
|
---|
| 958 |
|
---|
| 959 | i++;
|
---|
| 960 | }
|
---|
| 961 | /* Reset all submatches that are not within all of their parent
|
---|
| 962 | submatches. */
|
---|
| 963 | i = 0;
|
---|
| 964 | while (i < tnfa->num_submatches && i < nmatch)
|
---|
| 965 | {
|
---|
| 966 | if (pmatch[i].rm_eo == -1)
|
---|
| 967 | assert(pmatch[i].rm_so == -1);
|
---|
| 968 | assert(pmatch[i].rm_so <= pmatch[i].rm_eo);
|
---|
| 969 |
|
---|
| 970 | parents = submatch_data[i].parents;
|
---|
| 971 | if (parents != NULL)
|
---|
| 972 | for (j = 0; parents[j] >= 0; j++)
|
---|
| 973 | {
|
---|
| 974 | if (pmatch[i].rm_so < pmatch[parents[j]].rm_so
|
---|
| 975 | || pmatch[i].rm_eo > pmatch[parents[j]].rm_eo)
|
---|
| 976 | pmatch[i].rm_so = pmatch[i].rm_eo = -1;
|
---|
| 977 | }
|
---|
| 978 | i++;
|
---|
| 979 | }
|
---|
| 980 | }
|
---|
| 981 |
|
---|
| 982 | while (i < nmatch)
|
---|
| 983 | {
|
---|
| 984 | pmatch[i].rm_so = -1;
|
---|
| 985 | pmatch[i].rm_eo = -1;
|
---|
| 986 | i++;
|
---|
| 987 | }
|
---|
| 988 | }
|
---|
| 989 |
|
---|
| 990 |
|
---|
| 991 | /*
|
---|
| 992 | Wrapper functions for POSIX compatible regexp matching.
|
---|
| 993 | */
|
---|
| 994 |
|
---|
| 995 | int
|
---|
| 996 | regexec(const regex_t *restrict preg, const char *restrict string,
|
---|
| 997 | size_t nmatch, regmatch_t pmatch[restrict], int eflags)
|
---|
| 998 | {
|
---|
| 999 | tre_tnfa_t *tnfa = (void *)preg->TRE_REGEX_T_FIELD;
|
---|
| 1000 | reg_errcode_t status;
|
---|
| 1001 | regoff_t *tags = NULL, eo;
|
---|
| 1002 | if (tnfa->cflags & REG_NOSUB) nmatch = 0;
|
---|
| 1003 | if (tnfa->num_tags > 0 && nmatch > 0)
|
---|
| 1004 | {
|
---|
| 1005 | tags = xmalloc(sizeof(*tags) * tnfa->num_tags);
|
---|
| 1006 | if (tags == NULL)
|
---|
| 1007 | return REG_ESPACE;
|
---|
| 1008 | }
|
---|
| 1009 |
|
---|
| 1010 | /* Dispatch to the appropriate matcher. */
|
---|
| 1011 | if (tnfa->have_backrefs)
|
---|
| 1012 | {
|
---|
| 1013 | /* The regex has back references, use the backtracking matcher. */
|
---|
| 1014 | status = tre_tnfa_run_backtrack(tnfa, string, tags, eflags, &eo);
|
---|
| 1015 | }
|
---|
| 1016 | else
|
---|
| 1017 | {
|
---|
| 1018 | /* Exact matching, no back references, use the parallel matcher. */
|
---|
| 1019 | status = tre_tnfa_run_parallel(tnfa, string, tags, eflags, &eo);
|
---|
| 1020 | }
|
---|
| 1021 |
|
---|
| 1022 | if (status == REG_OK)
|
---|
| 1023 | /* A match was found, so fill the submatch registers. */
|
---|
| 1024 | tre_fill_pmatch(nmatch, pmatch, tnfa->cflags, tnfa, tags, eo);
|
---|
| 1025 | if (tags)
|
---|
| 1026 | xfree(tags);
|
---|
| 1027 | return status;
|
---|
| 1028 | }
|
---|