1 | /*
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2 | regcomp.c - TRE POSIX compatible regex compilation functions.
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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 <string.h>
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33 | #include <stdlib.h>
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34 | #include <regex.h>
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35 | #include <limits.h>
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36 | #include <stdint.h>
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37 | #include <ctype.h>
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38 |
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39 | #include "tre.h"
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40 |
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41 | #include <assert.h>
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42 |
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43 | /***********************************************************************
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44 | from tre-compile.h
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45 | ***********************************************************************/
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46 |
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47 | typedef struct {
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48 | int position;
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49 | int code_min;
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50 | int code_max;
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51 | int *tags;
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52 | int assertions;
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53 | tre_ctype_t class;
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54 | tre_ctype_t *neg_classes;
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55 | int backref;
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56 | } tre_pos_and_tags_t;
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57 |
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58 |
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59 | /***********************************************************************
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60 | from tre-ast.c and tre-ast.h
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61 | ***********************************************************************/
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62 |
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63 | /* The different AST node types. */
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64 | typedef enum {
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65 | LITERAL,
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66 | CATENATION,
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67 | ITERATION,
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68 | UNION
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69 | } tre_ast_type_t;
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70 |
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71 | /* Special subtypes of TRE_LITERAL. */
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72 | #define EMPTY -1 /* Empty leaf (denotes empty string). */
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73 | #define ASSERTION -2 /* Assertion leaf. */
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74 | #define TAG -3 /* Tag leaf. */
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75 | #define BACKREF -4 /* Back reference leaf. */
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76 |
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77 | #define IS_SPECIAL(x) ((x)->code_min < 0)
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78 | #define IS_EMPTY(x) ((x)->code_min == EMPTY)
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79 | #define IS_ASSERTION(x) ((x)->code_min == ASSERTION)
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80 | #define IS_TAG(x) ((x)->code_min == TAG)
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81 | #define IS_BACKREF(x) ((x)->code_min == BACKREF)
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82 |
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83 |
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84 | /* A generic AST node. All AST nodes consist of this node on the top
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85 | level with `obj' pointing to the actual content. */
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86 | typedef struct {
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87 | tre_ast_type_t type; /* Type of the node. */
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88 | void *obj; /* Pointer to actual node. */
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89 | int nullable;
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90 | int submatch_id;
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91 | int num_submatches;
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92 | int num_tags;
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93 | tre_pos_and_tags_t *firstpos;
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94 | tre_pos_and_tags_t *lastpos;
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95 | } tre_ast_node_t;
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96 |
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97 |
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98 | /* A "literal" node. These are created for assertions, back references,
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99 | tags, matching parameter settings, and all expressions that match one
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100 | character. */
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101 | typedef struct {
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102 | long code_min;
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103 | long code_max;
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104 | int position;
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105 | tre_ctype_t class;
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106 | tre_ctype_t *neg_classes;
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107 | } tre_literal_t;
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108 |
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109 | /* A "catenation" node. These are created when two regexps are concatenated.
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110 | If there are more than one subexpressions in sequence, the `left' part
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111 | holds all but the last, and `right' part holds the last subexpression
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112 | (catenation is left associative). */
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113 | typedef struct {
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114 | tre_ast_node_t *left;
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115 | tre_ast_node_t *right;
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116 | } tre_catenation_t;
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117 |
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118 | /* An "iteration" node. These are created for the "*", "+", "?", and "{m,n}"
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119 | operators. */
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120 | typedef struct {
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121 | /* Subexpression to match. */
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122 | tre_ast_node_t *arg;
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123 | /* Minimum number of consecutive matches. */
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124 | int min;
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125 | /* Maximum number of consecutive matches. */
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126 | int max;
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127 | /* If 0, match as many characters as possible, if 1 match as few as
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128 | possible. Note that this does not always mean the same thing as
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129 | matching as many/few repetitions as possible. */
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130 | unsigned int minimal:1;
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131 | } tre_iteration_t;
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132 |
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133 | /* An "union" node. These are created for the "|" operator. */
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134 | typedef struct {
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135 | tre_ast_node_t *left;
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136 | tre_ast_node_t *right;
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137 | } tre_union_t;
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138 |
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139 |
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140 | static tre_ast_node_t *
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141 | tre_ast_new_node(tre_mem_t mem, int type, void *obj)
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142 | {
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143 | tre_ast_node_t *node = tre_mem_calloc(mem, sizeof *node);
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144 | if (!node || !obj)
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145 | return 0;
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146 | node->obj = obj;
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147 | node->type = type;
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148 | node->nullable = -1;
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149 | node->submatch_id = -1;
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150 | return node;
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151 | }
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152 |
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153 | static tre_ast_node_t *
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154 | tre_ast_new_literal(tre_mem_t mem, int code_min, int code_max, int position)
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155 | {
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156 | tre_ast_node_t *node;
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157 | tre_literal_t *lit;
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158 |
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159 | lit = tre_mem_calloc(mem, sizeof *lit);
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160 | node = tre_ast_new_node(mem, LITERAL, lit);
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161 | if (!node)
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162 | return 0;
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163 | lit->code_min = code_min;
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164 | lit->code_max = code_max;
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165 | lit->position = position;
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166 | return node;
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167 | }
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168 |
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169 | static tre_ast_node_t *
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170 | tre_ast_new_iter(tre_mem_t mem, tre_ast_node_t *arg, int min, int max, int minimal)
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171 | {
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172 | tre_ast_node_t *node;
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173 | tre_iteration_t *iter;
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174 |
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175 | iter = tre_mem_calloc(mem, sizeof *iter);
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176 | node = tre_ast_new_node(mem, ITERATION, iter);
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177 | if (!node)
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178 | return 0;
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179 | iter->arg = arg;
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180 | iter->min = min;
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181 | iter->max = max;
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182 | iter->minimal = minimal;
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183 | node->num_submatches = arg->num_submatches;
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184 | return node;
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185 | }
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186 |
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187 | static tre_ast_node_t *
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188 | tre_ast_new_union(tre_mem_t mem, tre_ast_node_t *left, tre_ast_node_t *right)
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189 | {
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190 | tre_ast_node_t *node;
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191 | tre_union_t *un;
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192 |
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193 | if (!left)
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194 | return right;
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195 | un = tre_mem_calloc(mem, sizeof *un);
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196 | node = tre_ast_new_node(mem, UNION, un);
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197 | if (!node || !right)
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198 | return 0;
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199 | un->left = left;
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200 | un->right = right;
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201 | node->num_submatches = left->num_submatches + right->num_submatches;
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202 | return node;
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203 | }
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204 |
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205 | static tre_ast_node_t *
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206 | tre_ast_new_catenation(tre_mem_t mem, tre_ast_node_t *left, tre_ast_node_t *right)
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207 | {
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208 | tre_ast_node_t *node;
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209 | tre_catenation_t *cat;
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210 |
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211 | if (!left)
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212 | return right;
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213 | cat = tre_mem_calloc(mem, sizeof *cat);
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214 | node = tre_ast_new_node(mem, CATENATION, cat);
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215 | if (!node)
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216 | return 0;
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217 | cat->left = left;
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218 | cat->right = right;
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219 | node->num_submatches = left->num_submatches + right->num_submatches;
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220 | return node;
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221 | }
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222 |
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223 |
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224 | /***********************************************************************
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225 | from tre-stack.c and tre-stack.h
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226 | ***********************************************************************/
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227 |
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228 | typedef struct tre_stack_rec tre_stack_t;
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229 |
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230 | /* Creates a new stack object. `size' is initial size in bytes, `max_size'
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231 | is maximum size, and `increment' specifies how much more space will be
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232 | allocated with realloc() if all space gets used up. Returns the stack
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233 | object or NULL if out of memory. */
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234 | static tre_stack_t *
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235 | tre_stack_new(int size, int max_size, int increment);
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236 |
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237 | /* Frees the stack object. */
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238 | static void
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239 | tre_stack_destroy(tre_stack_t *s);
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240 |
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241 | /* Returns the current number of objects in the stack. */
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242 | static int
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243 | tre_stack_num_objects(tre_stack_t *s);
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244 |
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245 | /* Each tre_stack_push_*(tre_stack_t *s, <type> value) function pushes
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246 | `value' on top of stack `s'. Returns REG_ESPACE if out of memory.
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247 | This tries to realloc() more space before failing if maximum size
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248 | has not yet been reached. Returns REG_OK if successful. */
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249 | #define declare_pushf(typetag, type) \
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250 | static reg_errcode_t tre_stack_push_ ## typetag(tre_stack_t *s, type value)
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251 |
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252 | declare_pushf(voidptr, void *);
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253 | declare_pushf(int, int);
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254 |
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255 | /* Each tre_stack_pop_*(tre_stack_t *s) function pops the topmost
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256 | element off of stack `s' and returns it. The stack must not be
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257 | empty. */
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258 | #define declare_popf(typetag, type) \
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259 | static type tre_stack_pop_ ## typetag(tre_stack_t *s)
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260 |
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261 | declare_popf(voidptr, void *);
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262 | declare_popf(int, int);
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263 |
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264 | /* Just to save some typing. */
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265 | #define STACK_PUSH(s, typetag, value) \
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266 | do \
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267 | { \
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268 | status = tre_stack_push_ ## typetag(s, value); \
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269 | } \
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270 | while (/*CONSTCOND*/0)
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271 |
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272 | #define STACK_PUSHX(s, typetag, value) \
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273 | { \
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274 | status = tre_stack_push_ ## typetag(s, value); \
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275 | if (status != REG_OK) \
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276 | break; \
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277 | }
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278 |
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279 | #define STACK_PUSHR(s, typetag, value) \
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280 | { \
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281 | reg_errcode_t _status; \
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282 | _status = tre_stack_push_ ## typetag(s, value); \
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283 | if (_status != REG_OK) \
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284 | return _status; \
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285 | }
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286 |
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287 | union tre_stack_item {
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288 | void *voidptr_value;
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289 | int int_value;
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290 | };
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291 |
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292 | struct tre_stack_rec {
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293 | int size;
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294 | int max_size;
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295 | int increment;
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296 | int ptr;
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297 | union tre_stack_item *stack;
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298 | };
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299 |
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300 |
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301 | static tre_stack_t *
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302 | tre_stack_new(int size, int max_size, int increment)
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303 | {
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304 | tre_stack_t *s;
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305 |
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306 | s = xmalloc(sizeof(*s));
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307 | if (s != NULL)
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308 | {
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309 | s->stack = xmalloc(sizeof(*s->stack) * size);
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310 | if (s->stack == NULL)
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311 | {
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312 | xfree(s);
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313 | return NULL;
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314 | }
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315 | s->size = size;
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316 | s->max_size = max_size;
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317 | s->increment = increment;
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318 | s->ptr = 0;
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319 | }
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320 | return s;
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321 | }
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322 |
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323 | static void
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324 | tre_stack_destroy(tre_stack_t *s)
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325 | {
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326 | xfree(s->stack);
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327 | xfree(s);
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328 | }
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329 |
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330 | static int
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331 | tre_stack_num_objects(tre_stack_t *s)
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332 | {
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333 | return s->ptr;
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334 | }
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335 |
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336 | static reg_errcode_t
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337 | tre_stack_push(tre_stack_t *s, union tre_stack_item value)
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338 | {
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339 | if (s->ptr < s->size)
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340 | {
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341 | s->stack[s->ptr] = value;
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342 | s->ptr++;
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343 | }
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344 | else
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345 | {
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346 | if (s->size >= s->max_size)
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347 | {
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348 | return REG_ESPACE;
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349 | }
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350 | else
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351 | {
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352 | union tre_stack_item *new_buffer;
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353 | int new_size;
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354 | new_size = s->size + s->increment;
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355 | if (new_size > s->max_size)
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356 | new_size = s->max_size;
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357 | new_buffer = xrealloc(s->stack, sizeof(*new_buffer) * new_size);
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358 | if (new_buffer == NULL)
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359 | {
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360 | return REG_ESPACE;
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361 | }
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362 | assert(new_size > s->size);
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363 | s->size = new_size;
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364 | s->stack = new_buffer;
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365 | tre_stack_push(s, value);
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366 | }
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367 | }
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368 | return REG_OK;
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369 | }
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370 |
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371 | #define define_pushf(typetag, type) \
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372 | declare_pushf(typetag, type) { \
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373 | union tre_stack_item item; \
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374 | item.typetag ## _value = value; \
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375 | return tre_stack_push(s, item); \
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376 | }
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377 |
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378 | define_pushf(int, int)
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379 | define_pushf(voidptr, void *)
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380 |
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381 | #define define_popf(typetag, type) \
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382 | declare_popf(typetag, type) { \
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383 | return s->stack[--s->ptr].typetag ## _value; \
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384 | }
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385 |
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386 | define_popf(int, int)
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387 | define_popf(voidptr, void *)
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388 |
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389 |
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390 | /***********************************************************************
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391 | from tre-parse.c and tre-parse.h
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392 | ***********************************************************************/
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393 |
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394 | /* Parse context. */
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395 | typedef struct {
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396 | /* Memory allocator. The AST is allocated using this. */
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397 | tre_mem_t mem;
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398 | /* Stack used for keeping track of regexp syntax. */
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399 | tre_stack_t *stack;
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400 | /* The parsed node after a parse function returns. */
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401 | tre_ast_node_t *n;
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402 | /* Position in the regexp pattern after a parse function returns. */
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403 | const char *s;
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404 | /* The first character of the last subexpression parsed. */
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405 | const char *start;
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406 | /* Current submatch ID. */
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407 | int submatch_id;
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408 | /* Current position (number of literal). */
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409 | int position;
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410 | /* The highest back reference or -1 if none seen so far. */
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411 | int max_backref;
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412 | /* Compilation flags. */
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413 | int cflags;
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414 | } tre_parse_ctx_t;
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415 |
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416 | /* Some macros for expanding \w, \s, etc. */
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417 | static const struct {
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418 | char c;
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419 | const char *expansion;
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420 | } tre_macros[] = {
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421 | {'t', "\t"}, {'n', "\n"}, {'r', "\r"},
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422 | {'f', "\f"}, {'a', "\a"}, {'e', "\033"},
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423 | {'w', "[[:alnum:]_]"}, {'W', "[^[:alnum:]_]"}, {'s', "[[:space:]]"},
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424 | {'S', "[^[:space:]]"}, {'d', "[[:digit:]]"}, {'D', "[^[:digit:]]"},
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425 | { 0, 0 }
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426 | };
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427 |
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428 | /* Expands a macro delimited by `regex' and `regex_end' to `buf', which
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429 | must have at least `len' items. Sets buf[0] to zero if the there
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430 | is no match in `tre_macros'. */
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431 | static const char *tre_expand_macro(const char *s)
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432 | {
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433 | int i;
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434 | for (i = 0; tre_macros[i].c && tre_macros[i].c != *s; i++);
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435 | return tre_macros[i].expansion;
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436 | }
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437 |
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438 | static int
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439 | tre_compare_lit(const void *a, const void *b)
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440 | {
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441 | const tre_literal_t *const *la = a;
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442 | const tre_literal_t *const *lb = b;
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443 | /* assumes the range of valid code_min is < INT_MAX */
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444 | return la[0]->code_min - lb[0]->code_min;
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445 | }
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446 |
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447 | struct literals {
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448 | tre_mem_t mem;
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449 | tre_literal_t **a;
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450 | int len;
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451 | int cap;
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452 | };
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453 |
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454 | static tre_literal_t *tre_new_lit(struct literals *p)
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455 | {
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456 | tre_literal_t **a;
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457 | if (p->len >= p->cap) {
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458 | if (p->cap >= 1<<15)
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459 | return 0;
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460 | p->cap *= 2;
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461 | a = xrealloc(p->a, p->cap * sizeof *p->a);
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462 | if (!a)
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463 | return 0;
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464 | p->a = a;
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465 | }
|
---|
466 | a = p->a + p->len++;
|
---|
467 | *a = tre_mem_calloc(p->mem, sizeof **a);
|
---|
468 | return *a;
|
---|
469 | }
|
---|
470 |
|
---|
471 | static int add_icase_literals(struct literals *ls, int min, int max)
|
---|
472 | {
|
---|
473 | tre_literal_t *lit;
|
---|
474 | int b, e, c;
|
---|
475 | for (c=min; c<=max; ) {
|
---|
476 | /* assumes islower(c) and isupper(c) are exclusive
|
---|
477 | and toupper(c)!=c if islower(c).
|
---|
478 | multiple opposite case characters are not supported */
|
---|
479 | if (tre_islower(c)) {
|
---|
480 | b = e = tre_toupper(c);
|
---|
481 | for (c++, e++; c<=max; c++, e++)
|
---|
482 | if (tre_toupper(c) != e) break;
|
---|
483 | } else if (tre_isupper(c)) {
|
---|
484 | b = e = tre_tolower(c);
|
---|
485 | for (c++, e++; c<=max; c++, e++)
|
---|
486 | if (tre_tolower(c) != e) break;
|
---|
487 | } else {
|
---|
488 | c++;
|
---|
489 | continue;
|
---|
490 | }
|
---|
491 | lit = tre_new_lit(ls);
|
---|
492 | if (!lit)
|
---|
493 | return -1;
|
---|
494 | lit->code_min = b;
|
---|
495 | lit->code_max = e-1;
|
---|
496 | lit->position = -1;
|
---|
497 | }
|
---|
498 | return 0;
|
---|
499 | }
|
---|
500 |
|
---|
501 |
|
---|
502 | /* Maximum number of character classes in a negated bracket expression. */
|
---|
503 | #define MAX_NEG_CLASSES 64
|
---|
504 |
|
---|
505 | struct neg {
|
---|
506 | int negate;
|
---|
507 | int len;
|
---|
508 | tre_ctype_t a[MAX_NEG_CLASSES];
|
---|
509 | };
|
---|
510 |
|
---|
511 | // TODO: parse bracket into a set of non-overlapping [lo,hi] ranges
|
---|
512 |
|
---|
513 | /*
|
---|
514 | bracket grammar:
|
---|
515 | Bracket = '[' List ']' | '[^' List ']'
|
---|
516 | List = Term | List Term
|
---|
517 | Term = Char | Range | Chclass | Eqclass
|
---|
518 | Range = Char '-' Char | Char '-' '-'
|
---|
519 | Char = Coll | coll_single
|
---|
520 | Meta = ']' | '-'
|
---|
521 | Coll = '[.' coll_single '.]' | '[.' coll_multi '.]' | '[.' Meta '.]'
|
---|
522 | Eqclass = '[=' coll_single '=]' | '[=' coll_multi '=]'
|
---|
523 | Chclass = '[:' class ':]'
|
---|
524 |
|
---|
525 | coll_single is a single char collating element but it can be
|
---|
526 | '-' only at the beginning or end of a List and
|
---|
527 | ']' only at the beginning of a List and
|
---|
528 | '^' anywhere except after the openning '['
|
---|
529 | */
|
---|
530 |
|
---|
531 | static reg_errcode_t parse_bracket_terms(tre_parse_ctx_t *ctx, const char *s, struct literals *ls, struct neg *neg)
|
---|
532 | {
|
---|
533 | const char *start = s;
|
---|
534 | tre_ctype_t class;
|
---|
535 | int min, max;
|
---|
536 | wchar_t wc;
|
---|
537 | int len;
|
---|
538 |
|
---|
539 | for (;;) {
|
---|
540 | class = 0;
|
---|
541 | len = mbtowc(&wc, s, -1);
|
---|
542 | if (len <= 0)
|
---|
543 | return *s ? REG_BADPAT : REG_EBRACK;
|
---|
544 | if (*s == ']' && s != start) {
|
---|
545 | ctx->s = s+1;
|
---|
546 | return REG_OK;
|
---|
547 | }
|
---|
548 | if (*s == '-' && s != start && s[1] != ']' &&
|
---|
549 | /* extension: [a-z--@] is accepted as [a-z]|[--@] */
|
---|
550 | (s[1] != '-' || s[2] == ']'))
|
---|
551 | return REG_ERANGE;
|
---|
552 | if (*s == '[' && (s[1] == '.' || s[1] == '='))
|
---|
553 | /* collating symbols and equivalence classes are not supported */
|
---|
554 | return REG_ECOLLATE;
|
---|
555 | if (*s == '[' && s[1] == ':') {
|
---|
556 | char tmp[CHARCLASS_NAME_MAX+1];
|
---|
557 | s += 2;
|
---|
558 | for (len=0; len < CHARCLASS_NAME_MAX && s[len]; len++) {
|
---|
559 | if (s[len] == ':') {
|
---|
560 | memcpy(tmp, s, len);
|
---|
561 | tmp[len] = 0;
|
---|
562 | class = tre_ctype(tmp);
|
---|
563 | break;
|
---|
564 | }
|
---|
565 | }
|
---|
566 | if (!class || s[len+1] != ']')
|
---|
567 | return REG_ECTYPE;
|
---|
568 | min = 0;
|
---|
569 | max = TRE_CHAR_MAX;
|
---|
570 | s += len+2;
|
---|
571 | } else {
|
---|
572 | min = max = wc;
|
---|
573 | s += len;
|
---|
574 | if (*s == '-' && s[1] != ']') {
|
---|
575 | s++;
|
---|
576 | len = mbtowc(&wc, s, -1);
|
---|
577 | max = wc;
|
---|
578 | /* XXX - Should use collation order instead of
|
---|
579 | encoding values in character ranges. */
|
---|
580 | if (len <= 0 || min > max)
|
---|
581 | return REG_ERANGE;
|
---|
582 | s += len;
|
---|
583 | }
|
---|
584 | }
|
---|
585 |
|
---|
586 | if (class && neg->negate) {
|
---|
587 | if (neg->len >= MAX_NEG_CLASSES)
|
---|
588 | return REG_ESPACE;
|
---|
589 | neg->a[neg->len++] = class;
|
---|
590 | } else {
|
---|
591 | tre_literal_t *lit = tre_new_lit(ls);
|
---|
592 | if (!lit)
|
---|
593 | return REG_ESPACE;
|
---|
594 | lit->code_min = min;
|
---|
595 | lit->code_max = max;
|
---|
596 | lit->class = class;
|
---|
597 | lit->position = -1;
|
---|
598 |
|
---|
599 | /* Add opposite-case codepoints if REG_ICASE is present.
|
---|
600 | It seems that POSIX requires that bracket negation
|
---|
601 | should happen before case-folding, but most practical
|
---|
602 | implementations do it the other way around. Changing
|
---|
603 | the order would need efficient representation of
|
---|
604 | case-fold ranges and bracket range sets even with
|
---|
605 | simple patterns so this is ok for now. */
|
---|
606 | if (ctx->cflags & REG_ICASE && !class)
|
---|
607 | if (add_icase_literals(ls, min, max))
|
---|
608 | return REG_ESPACE;
|
---|
609 | }
|
---|
610 | }
|
---|
611 | }
|
---|
612 |
|
---|
613 | static reg_errcode_t parse_bracket(tre_parse_ctx_t *ctx, const char *s)
|
---|
614 | {
|
---|
615 | int i, max, min, negmax, negmin;
|
---|
616 | tre_ast_node_t *node = 0, *n;
|
---|
617 | tre_ctype_t *nc = 0;
|
---|
618 | tre_literal_t *lit;
|
---|
619 | struct literals ls;
|
---|
620 | struct neg neg;
|
---|
621 | reg_errcode_t err;
|
---|
622 |
|
---|
623 | ls.mem = ctx->mem;
|
---|
624 | ls.len = 0;
|
---|
625 | ls.cap = 32;
|
---|
626 | ls.a = xmalloc(ls.cap * sizeof *ls.a);
|
---|
627 | if (!ls.a)
|
---|
628 | return REG_ESPACE;
|
---|
629 | neg.len = 0;
|
---|
630 | neg.negate = *s == '^';
|
---|
631 | if (neg.negate)
|
---|
632 | s++;
|
---|
633 |
|
---|
634 | err = parse_bracket_terms(ctx, s, &ls, &neg);
|
---|
635 | if (err != REG_OK)
|
---|
636 | goto parse_bracket_done;
|
---|
637 |
|
---|
638 | if (neg.negate) {
|
---|
639 | /*
|
---|
640 | * With REG_NEWLINE, POSIX requires that newlines are not matched by
|
---|
641 | * any form of a non-matching list.
|
---|
642 | */
|
---|
643 | if (ctx->cflags & REG_NEWLINE) {
|
---|
644 | lit = tre_new_lit(&ls);
|
---|
645 | if (!lit) {
|
---|
646 | err = REG_ESPACE;
|
---|
647 | goto parse_bracket_done;
|
---|
648 | }
|
---|
649 | lit->code_min = '\n';
|
---|
650 | lit->code_max = '\n';
|
---|
651 | lit->position = -1;
|
---|
652 | }
|
---|
653 | /* Sort the array if we need to negate it. */
|
---|
654 | qsort(ls.a, ls.len, sizeof *ls.a, tre_compare_lit);
|
---|
655 | /* extra lit for the last negated range */
|
---|
656 | lit = tre_new_lit(&ls);
|
---|
657 | if (!lit) {
|
---|
658 | err = REG_ESPACE;
|
---|
659 | goto parse_bracket_done;
|
---|
660 | }
|
---|
661 | lit->code_min = TRE_CHAR_MAX+1;
|
---|
662 | lit->code_max = TRE_CHAR_MAX+1;
|
---|
663 | lit->position = -1;
|
---|
664 | /* negated classes */
|
---|
665 | if (neg.len) {
|
---|
666 | nc = tre_mem_alloc(ctx->mem, (neg.len+1)*sizeof *neg.a);
|
---|
667 | if (!nc) {
|
---|
668 | err = REG_ESPACE;
|
---|
669 | goto parse_bracket_done;
|
---|
670 | }
|
---|
671 | memcpy(nc, neg.a, neg.len*sizeof *neg.a);
|
---|
672 | nc[neg.len] = 0;
|
---|
673 | }
|
---|
674 | }
|
---|
675 |
|
---|
676 | /* Build a union of the items in the array, negated if necessary. */
|
---|
677 | negmax = negmin = 0;
|
---|
678 | for (i = 0; i < ls.len; i++) {
|
---|
679 | lit = ls.a[i];
|
---|
680 | min = lit->code_min;
|
---|
681 | max = lit->code_max;
|
---|
682 | if (neg.negate) {
|
---|
683 | if (min <= negmin) {
|
---|
684 | /* Overlap. */
|
---|
685 | negmin = MAX(max + 1, negmin);
|
---|
686 | continue;
|
---|
687 | }
|
---|
688 | negmax = min - 1;
|
---|
689 | lit->code_min = negmin;
|
---|
690 | lit->code_max = negmax;
|
---|
691 | negmin = max + 1;
|
---|
692 | }
|
---|
693 | lit->position = ctx->position;
|
---|
694 | lit->neg_classes = nc;
|
---|
695 | n = tre_ast_new_node(ctx->mem, LITERAL, lit);
|
---|
696 | node = tre_ast_new_union(ctx->mem, node, n);
|
---|
697 | if (!node) {
|
---|
698 | err = REG_ESPACE;
|
---|
699 | break;
|
---|
700 | }
|
---|
701 | }
|
---|
702 |
|
---|
703 | parse_bracket_done:
|
---|
704 | xfree(ls.a);
|
---|
705 | ctx->position++;
|
---|
706 | ctx->n = node;
|
---|
707 | return err;
|
---|
708 | }
|
---|
709 |
|
---|
710 | static const char *parse_dup_count(const char *s, int *n)
|
---|
711 | {
|
---|
712 | *n = -1;
|
---|
713 | if (!isdigit(*s))
|
---|
714 | return s;
|
---|
715 | *n = 0;
|
---|
716 | for (;;) {
|
---|
717 | *n = 10 * *n + (*s - '0');
|
---|
718 | s++;
|
---|
719 | if (!isdigit(*s) || *n > RE_DUP_MAX)
|
---|
720 | break;
|
---|
721 | }
|
---|
722 | return s;
|
---|
723 | }
|
---|
724 |
|
---|
725 | static const char *parse_dup(const char *s, int ere, int *pmin, int *pmax)
|
---|
726 | {
|
---|
727 | int min, max;
|
---|
728 |
|
---|
729 | s = parse_dup_count(s, &min);
|
---|
730 | if (*s == ',')
|
---|
731 | s = parse_dup_count(s+1, &max);
|
---|
732 | else
|
---|
733 | max = min;
|
---|
734 |
|
---|
735 | if (
|
---|
736 | (max < min && max >= 0) ||
|
---|
737 | max > RE_DUP_MAX ||
|
---|
738 | min > RE_DUP_MAX ||
|
---|
739 | min < 0 ||
|
---|
740 | (!ere && *s++ != '\\') ||
|
---|
741 | *s++ != '}'
|
---|
742 | )
|
---|
743 | return 0;
|
---|
744 | *pmin = min;
|
---|
745 | *pmax = max;
|
---|
746 | return s;
|
---|
747 | }
|
---|
748 |
|
---|
749 | static int hexval(unsigned c)
|
---|
750 | {
|
---|
751 | if (c-'0'<10) return c-'0';
|
---|
752 | c |= 32;
|
---|
753 | if (c-'a'<6) return c-'a'+10;
|
---|
754 | return -1;
|
---|
755 | }
|
---|
756 |
|
---|
757 | static reg_errcode_t marksub(tre_parse_ctx_t *ctx, tre_ast_node_t *node, int subid)
|
---|
758 | {
|
---|
759 | if (node->submatch_id >= 0) {
|
---|
760 | tre_ast_node_t *n = tre_ast_new_literal(ctx->mem, EMPTY, -1, -1);
|
---|
761 | if (!n)
|
---|
762 | return REG_ESPACE;
|
---|
763 | n = tre_ast_new_catenation(ctx->mem, n, node);
|
---|
764 | if (!n)
|
---|
765 | return REG_ESPACE;
|
---|
766 | n->num_submatches = node->num_submatches;
|
---|
767 | node = n;
|
---|
768 | }
|
---|
769 | node->submatch_id = subid;
|
---|
770 | node->num_submatches++;
|
---|
771 | ctx->n = node;
|
---|
772 | return REG_OK;
|
---|
773 | }
|
---|
774 |
|
---|
775 | /*
|
---|
776 | BRE grammar:
|
---|
777 | Regex = Branch | '^' | '$' | '^$' | '^' Branch | Branch '$' | '^' Branch '$'
|
---|
778 | Branch = Atom | Branch Atom
|
---|
779 | Atom = char | quoted_char | '.' | Bracket | Atom Dup | '\(' Branch '\)' | back_ref
|
---|
780 | Dup = '*' | '\{' Count '\}' | '\{' Count ',\}' | '\{' Count ',' Count '\}'
|
---|
781 |
|
---|
782 | (leading ^ and trailing $ in a sub expr may be an anchor or literal as well)
|
---|
783 |
|
---|
784 | ERE grammar:
|
---|
785 | Regex = Branch | Regex '|' Branch
|
---|
786 | Branch = Atom | Branch Atom
|
---|
787 | Atom = char | quoted_char | '.' | Bracket | Atom Dup | '(' Regex ')' | '^' | '$'
|
---|
788 | Dup = '*' | '+' | '?' | '{' Count '}' | '{' Count ',}' | '{' Count ',' Count '}'
|
---|
789 |
|
---|
790 | (a*+?, ^*, $+, \X, {, (|a) are unspecified)
|
---|
791 | */
|
---|
792 |
|
---|
793 | static reg_errcode_t parse_atom(tre_parse_ctx_t *ctx, const char *s)
|
---|
794 | {
|
---|
795 | int len, ere = ctx->cflags & REG_EXTENDED;
|
---|
796 | const char *p;
|
---|
797 | tre_ast_node_t *node;
|
---|
798 | wchar_t wc;
|
---|
799 | switch (*s) {
|
---|
800 | case '[':
|
---|
801 | return parse_bracket(ctx, s+1);
|
---|
802 | case '\\':
|
---|
803 | p = tre_expand_macro(s+1);
|
---|
804 | if (p) {
|
---|
805 | /* assume \X expansion is a single atom */
|
---|
806 | reg_errcode_t err = parse_atom(ctx, p);
|
---|
807 | ctx->s = s+2;
|
---|
808 | return err;
|
---|
809 | }
|
---|
810 | /* extensions: \b, \B, \<, \>, \xHH \x{HHHH} */
|
---|
811 | switch (*++s) {
|
---|
812 | case 0:
|
---|
813 | return REG_EESCAPE;
|
---|
814 | case 'b':
|
---|
815 | node = tre_ast_new_literal(ctx->mem, ASSERTION, ASSERT_AT_WB, -1);
|
---|
816 | break;
|
---|
817 | case 'B':
|
---|
818 | node = tre_ast_new_literal(ctx->mem, ASSERTION, ASSERT_AT_WB_NEG, -1);
|
---|
819 | break;
|
---|
820 | case '<':
|
---|
821 | node = tre_ast_new_literal(ctx->mem, ASSERTION, ASSERT_AT_BOW, -1);
|
---|
822 | break;
|
---|
823 | case '>':
|
---|
824 | node = tre_ast_new_literal(ctx->mem, ASSERTION, ASSERT_AT_EOW, -1);
|
---|
825 | break;
|
---|
826 | case 'x':
|
---|
827 | s++;
|
---|
828 | int i, v = 0, c;
|
---|
829 | len = 2;
|
---|
830 | if (*s == '{') {
|
---|
831 | len = 8;
|
---|
832 | s++;
|
---|
833 | }
|
---|
834 | for (i=0; i<len && v<0x110000; i++) {
|
---|
835 | c = hexval(s[i]);
|
---|
836 | if (c < 0) break;
|
---|
837 | v = 16*v + c;
|
---|
838 | }
|
---|
839 | s += i;
|
---|
840 | if (len == 8) {
|
---|
841 | if (*s != '}')
|
---|
842 | return REG_EBRACE;
|
---|
843 | s++;
|
---|
844 | }
|
---|
845 | node = tre_ast_new_literal(ctx->mem, v, v, ctx->position++);
|
---|
846 | s--;
|
---|
847 | break;
|
---|
848 | case '{':
|
---|
849 | case '+':
|
---|
850 | case '?':
|
---|
851 | /* extension: treat \+, \? as repetitions in BRE */
|
---|
852 | /* reject repetitions after empty expression in BRE */
|
---|
853 | if (!ere)
|
---|
854 | return REG_BADRPT;
|
---|
855 | case '|':
|
---|
856 | /* extension: treat \| as alternation in BRE */
|
---|
857 | if (!ere) {
|
---|
858 | node = tre_ast_new_literal(ctx->mem, EMPTY, -1, -1);
|
---|
859 | s--;
|
---|
860 | goto end;
|
---|
861 | }
|
---|
862 | /* fallthrough */
|
---|
863 | default:
|
---|
864 | if (!ere && (unsigned)*s-'1' < 9) {
|
---|
865 | /* back reference */
|
---|
866 | int val = *s - '0';
|
---|
867 | node = tre_ast_new_literal(ctx->mem, BACKREF, val, ctx->position++);
|
---|
868 | ctx->max_backref = MAX(val, ctx->max_backref);
|
---|
869 | } else {
|
---|
870 | /* extension: accept unknown escaped char
|
---|
871 | as a literal */
|
---|
872 | goto parse_literal;
|
---|
873 | }
|
---|
874 | }
|
---|
875 | s++;
|
---|
876 | break;
|
---|
877 | case '.':
|
---|
878 | if (ctx->cflags & REG_NEWLINE) {
|
---|
879 | tre_ast_node_t *tmp1, *tmp2;
|
---|
880 | tmp1 = tre_ast_new_literal(ctx->mem, 0, '\n'-1, ctx->position++);
|
---|
881 | tmp2 = tre_ast_new_literal(ctx->mem, '\n'+1, TRE_CHAR_MAX, ctx->position++);
|
---|
882 | if (tmp1 && tmp2)
|
---|
883 | node = tre_ast_new_union(ctx->mem, tmp1, tmp2);
|
---|
884 | else
|
---|
885 | node = 0;
|
---|
886 | } else {
|
---|
887 | node = tre_ast_new_literal(ctx->mem, 0, TRE_CHAR_MAX, ctx->position++);
|
---|
888 | }
|
---|
889 | s++;
|
---|
890 | break;
|
---|
891 | case '^':
|
---|
892 | /* '^' has a special meaning everywhere in EREs, and at beginning of BRE. */
|
---|
893 | if (!ere && s != ctx->start)
|
---|
894 | goto parse_literal;
|
---|
895 | node = tre_ast_new_literal(ctx->mem, ASSERTION, ASSERT_AT_BOL, -1);
|
---|
896 | s++;
|
---|
897 | break;
|
---|
898 | case '$':
|
---|
899 | /* '$' is special everywhere in EREs, and at the end of a BRE subexpression. */
|
---|
900 | if (!ere && s[1] && (s[1]!='\\'|| (s[2]!=')' && s[2]!='|')))
|
---|
901 | goto parse_literal;
|
---|
902 | node = tre_ast_new_literal(ctx->mem, ASSERTION, ASSERT_AT_EOL, -1);
|
---|
903 | s++;
|
---|
904 | break;
|
---|
905 | case '*':
|
---|
906 | case '{':
|
---|
907 | case '+':
|
---|
908 | case '?':
|
---|
909 | /* reject repetitions after empty expression in ERE */
|
---|
910 | if (ere)
|
---|
911 | return REG_BADRPT;
|
---|
912 | case '|':
|
---|
913 | if (!ere)
|
---|
914 | goto parse_literal;
|
---|
915 | case 0:
|
---|
916 | node = tre_ast_new_literal(ctx->mem, EMPTY, -1, -1);
|
---|
917 | break;
|
---|
918 | default:
|
---|
919 | parse_literal:
|
---|
920 | len = mbtowc(&wc, s, -1);
|
---|
921 | if (len < 0)
|
---|
922 | return REG_BADPAT;
|
---|
923 | if (ctx->cflags & REG_ICASE && (tre_isupper(wc) || tre_islower(wc))) {
|
---|
924 | tre_ast_node_t *tmp1, *tmp2;
|
---|
925 | /* multiple opposite case characters are not supported */
|
---|
926 | tmp1 = tre_ast_new_literal(ctx->mem, tre_toupper(wc), tre_toupper(wc), ctx->position);
|
---|
927 | tmp2 = tre_ast_new_literal(ctx->mem, tre_tolower(wc), tre_tolower(wc), ctx->position);
|
---|
928 | if (tmp1 && tmp2)
|
---|
929 | node = tre_ast_new_union(ctx->mem, tmp1, tmp2);
|
---|
930 | else
|
---|
931 | node = 0;
|
---|
932 | } else {
|
---|
933 | node = tre_ast_new_literal(ctx->mem, wc, wc, ctx->position);
|
---|
934 | }
|
---|
935 | ctx->position++;
|
---|
936 | s += len;
|
---|
937 | break;
|
---|
938 | }
|
---|
939 | end:
|
---|
940 | if (!node)
|
---|
941 | return REG_ESPACE;
|
---|
942 | ctx->n = node;
|
---|
943 | ctx->s = s;
|
---|
944 | return REG_OK;
|
---|
945 | }
|
---|
946 |
|
---|
947 | #define PUSHPTR(err, s, v) do { \
|
---|
948 | if ((err = tre_stack_push_voidptr(s, v)) != REG_OK) \
|
---|
949 | return err; \
|
---|
950 | } while(0)
|
---|
951 |
|
---|
952 | #define PUSHINT(err, s, v) do { \
|
---|
953 | if ((err = tre_stack_push_int(s, v)) != REG_OK) \
|
---|
954 | return err; \
|
---|
955 | } while(0)
|
---|
956 |
|
---|
957 | static reg_errcode_t tre_parse(tre_parse_ctx_t *ctx)
|
---|
958 | {
|
---|
959 | tre_ast_node_t *nbranch=0, *nunion=0;
|
---|
960 | int ere = ctx->cflags & REG_EXTENDED;
|
---|
961 | const char *s = ctx->start;
|
---|
962 | int subid = 0;
|
---|
963 | int depth = 0;
|
---|
964 | reg_errcode_t err;
|
---|
965 | tre_stack_t *stack = ctx->stack;
|
---|
966 |
|
---|
967 | PUSHINT(err, stack, subid++);
|
---|
968 | for (;;) {
|
---|
969 | if ((!ere && *s == '\\' && s[1] == '(') ||
|
---|
970 | (ere && *s == '(')) {
|
---|
971 | PUSHPTR(err, stack, nunion);
|
---|
972 | PUSHPTR(err, stack, nbranch);
|
---|
973 | PUSHINT(err, stack, subid++);
|
---|
974 | s++;
|
---|
975 | if (!ere)
|
---|
976 | s++;
|
---|
977 | depth++;
|
---|
978 | nbranch = nunion = 0;
|
---|
979 | ctx->start = s;
|
---|
980 | continue;
|
---|
981 | }
|
---|
982 | if ((!ere && *s == '\\' && s[1] == ')') ||
|
---|
983 | (ere && *s == ')' && depth)) {
|
---|
984 | ctx->n = tre_ast_new_literal(ctx->mem, EMPTY, -1, -1);
|
---|
985 | if (!ctx->n)
|
---|
986 | return REG_ESPACE;
|
---|
987 | } else {
|
---|
988 | err = parse_atom(ctx, s);
|
---|
989 | if (err != REG_OK)
|
---|
990 | return err;
|
---|
991 | s = ctx->s;
|
---|
992 | }
|
---|
993 |
|
---|
994 | parse_iter:
|
---|
995 | for (;;) {
|
---|
996 | int min, max;
|
---|
997 |
|
---|
998 | if (*s!='\\' && *s!='*') {
|
---|
999 | if (!ere)
|
---|
1000 | break;
|
---|
1001 | if (*s!='+' && *s!='?' && *s!='{')
|
---|
1002 | break;
|
---|
1003 | }
|
---|
1004 | if (*s=='\\' && ere)
|
---|
1005 | break;
|
---|
1006 | /* extension: treat \+, \? as repetitions in BRE */
|
---|
1007 | if (*s=='\\' && s[1]!='+' && s[1]!='?' && s[1]!='{')
|
---|
1008 | break;
|
---|
1009 | if (*s=='\\')
|
---|
1010 | s++;
|
---|
1011 |
|
---|
1012 | /* handle ^* at the start of a BRE. */
|
---|
1013 | if (!ere && s==ctx->start+1 && s[-1]=='^')
|
---|
1014 | break;
|
---|
1015 |
|
---|
1016 | /* extension: multiple consecutive *+?{,} is unspecified,
|
---|
1017 | but (a+)+ has to be supported so accepting a++ makes
|
---|
1018 | sense, note however that the RE_DUP_MAX limit can be
|
---|
1019 | circumvented: (a{255}){255} uses a lot of memory.. */
|
---|
1020 | if (*s=='{') {
|
---|
1021 | s = parse_dup(s+1, ere, &min, &max);
|
---|
1022 | if (!s)
|
---|
1023 | return REG_BADBR;
|
---|
1024 | } else {
|
---|
1025 | min=0;
|
---|
1026 | max=-1;
|
---|
1027 | if (*s == '+')
|
---|
1028 | min = 1;
|
---|
1029 | if (*s == '?')
|
---|
1030 | max = 1;
|
---|
1031 | s++;
|
---|
1032 | }
|
---|
1033 | if (max == 0)
|
---|
1034 | ctx->n = tre_ast_new_literal(ctx->mem, EMPTY, -1, -1);
|
---|
1035 | else
|
---|
1036 | ctx->n = tre_ast_new_iter(ctx->mem, ctx->n, min, max, 0);
|
---|
1037 | if (!ctx->n)
|
---|
1038 | return REG_ESPACE;
|
---|
1039 | }
|
---|
1040 |
|
---|
1041 | nbranch = tre_ast_new_catenation(ctx->mem, nbranch, ctx->n);
|
---|
1042 | if ((ere && *s == '|') ||
|
---|
1043 | (ere && *s == ')' && depth) ||
|
---|
1044 | (!ere && *s == '\\' && s[1] == ')') ||
|
---|
1045 | /* extension: treat \| as alternation in BRE */
|
---|
1046 | (!ere && *s == '\\' && s[1] == '|') ||
|
---|
1047 | !*s) {
|
---|
1048 | /* extension: empty branch is unspecified (), (|a), (a|)
|
---|
1049 | here they are not rejected but match on empty string */
|
---|
1050 | int c = *s;
|
---|
1051 | nunion = tre_ast_new_union(ctx->mem, nunion, nbranch);
|
---|
1052 | nbranch = 0;
|
---|
1053 |
|
---|
1054 | if (c == '\\' && s[1] == '|') {
|
---|
1055 | s+=2;
|
---|
1056 | ctx->start = s;
|
---|
1057 | } else if (c == '|') {
|
---|
1058 | s++;
|
---|
1059 | ctx->start = s;
|
---|
1060 | } else {
|
---|
1061 | if (c == '\\') {
|
---|
1062 | if (!depth) return REG_EPAREN;
|
---|
1063 | s+=2;
|
---|
1064 | } else if (c == ')')
|
---|
1065 | s++;
|
---|
1066 | depth--;
|
---|
1067 | err = marksub(ctx, nunion, tre_stack_pop_int(stack));
|
---|
1068 | if (err != REG_OK)
|
---|
1069 | return err;
|
---|
1070 | if (!c && depth<0) {
|
---|
1071 | ctx->submatch_id = subid;
|
---|
1072 | return REG_OK;
|
---|
1073 | }
|
---|
1074 | if (!c || depth<0)
|
---|
1075 | return REG_EPAREN;
|
---|
1076 | nbranch = tre_stack_pop_voidptr(stack);
|
---|
1077 | nunion = tre_stack_pop_voidptr(stack);
|
---|
1078 | goto parse_iter;
|
---|
1079 | }
|
---|
1080 | }
|
---|
1081 | }
|
---|
1082 | }
|
---|
1083 |
|
---|
1084 |
|
---|
1085 | /***********************************************************************
|
---|
1086 | from tre-compile.c
|
---|
1087 | ***********************************************************************/
|
---|
1088 |
|
---|
1089 |
|
---|
1090 | /*
|
---|
1091 | TODO:
|
---|
1092 | - Fix tre_ast_to_tnfa() to recurse using a stack instead of recursive
|
---|
1093 | function calls.
|
---|
1094 | */
|
---|
1095 |
|
---|
1096 | /*
|
---|
1097 | Algorithms to setup tags so that submatch addressing can be done.
|
---|
1098 | */
|
---|
1099 |
|
---|
1100 |
|
---|
1101 | /* Inserts a catenation node to the root of the tree given in `node'.
|
---|
1102 | As the left child a new tag with number `tag_id' to `node' is added,
|
---|
1103 | and the right child is the old root. */
|
---|
1104 | static reg_errcode_t
|
---|
1105 | tre_add_tag_left(tre_mem_t mem, tre_ast_node_t *node, int tag_id)
|
---|
1106 | {
|
---|
1107 | tre_catenation_t *c;
|
---|
1108 |
|
---|
1109 | c = tre_mem_alloc(mem, sizeof(*c));
|
---|
1110 | if (c == NULL)
|
---|
1111 | return REG_ESPACE;
|
---|
1112 | c->left = tre_ast_new_literal(mem, TAG, tag_id, -1);
|
---|
1113 | if (c->left == NULL)
|
---|
1114 | return REG_ESPACE;
|
---|
1115 | c->right = tre_mem_alloc(mem, sizeof(tre_ast_node_t));
|
---|
1116 | if (c->right == NULL)
|
---|
1117 | return REG_ESPACE;
|
---|
1118 |
|
---|
1119 | c->right->obj = node->obj;
|
---|
1120 | c->right->type = node->type;
|
---|
1121 | c->right->nullable = -1;
|
---|
1122 | c->right->submatch_id = -1;
|
---|
1123 | c->right->firstpos = NULL;
|
---|
1124 | c->right->lastpos = NULL;
|
---|
1125 | c->right->num_tags = 0;
|
---|
1126 | c->right->num_submatches = 0;
|
---|
1127 | node->obj = c;
|
---|
1128 | node->type = CATENATION;
|
---|
1129 | return REG_OK;
|
---|
1130 | }
|
---|
1131 |
|
---|
1132 | /* Inserts a catenation node to the root of the tree given in `node'.
|
---|
1133 | As the right child a new tag with number `tag_id' to `node' is added,
|
---|
1134 | and the left child is the old root. */
|
---|
1135 | static reg_errcode_t
|
---|
1136 | tre_add_tag_right(tre_mem_t mem, tre_ast_node_t *node, int tag_id)
|
---|
1137 | {
|
---|
1138 | tre_catenation_t *c;
|
---|
1139 |
|
---|
1140 | c = tre_mem_alloc(mem, sizeof(*c));
|
---|
1141 | if (c == NULL)
|
---|
1142 | return REG_ESPACE;
|
---|
1143 | c->right = tre_ast_new_literal(mem, TAG, tag_id, -1);
|
---|
1144 | if (c->right == NULL)
|
---|
1145 | return REG_ESPACE;
|
---|
1146 | c->left = tre_mem_alloc(mem, sizeof(tre_ast_node_t));
|
---|
1147 | if (c->left == NULL)
|
---|
1148 | return REG_ESPACE;
|
---|
1149 |
|
---|
1150 | c->left->obj = node->obj;
|
---|
1151 | c->left->type = node->type;
|
---|
1152 | c->left->nullable = -1;
|
---|
1153 | c->left->submatch_id = -1;
|
---|
1154 | c->left->firstpos = NULL;
|
---|
1155 | c->left->lastpos = NULL;
|
---|
1156 | c->left->num_tags = 0;
|
---|
1157 | c->left->num_submatches = 0;
|
---|
1158 | node->obj = c;
|
---|
1159 | node->type = CATENATION;
|
---|
1160 | return REG_OK;
|
---|
1161 | }
|
---|
1162 |
|
---|
1163 | typedef enum {
|
---|
1164 | ADDTAGS_RECURSE,
|
---|
1165 | ADDTAGS_AFTER_ITERATION,
|
---|
1166 | ADDTAGS_AFTER_UNION_LEFT,
|
---|
1167 | ADDTAGS_AFTER_UNION_RIGHT,
|
---|
1168 | ADDTAGS_AFTER_CAT_LEFT,
|
---|
1169 | ADDTAGS_AFTER_CAT_RIGHT,
|
---|
1170 | ADDTAGS_SET_SUBMATCH_END
|
---|
1171 | } tre_addtags_symbol_t;
|
---|
1172 |
|
---|
1173 |
|
---|
1174 | typedef struct {
|
---|
1175 | int tag;
|
---|
1176 | int next_tag;
|
---|
1177 | } tre_tag_states_t;
|
---|
1178 |
|
---|
1179 |
|
---|
1180 | /* Go through `regset' and set submatch data for submatches that are
|
---|
1181 | using this tag. */
|
---|
1182 | static void
|
---|
1183 | tre_purge_regset(int *regset, tre_tnfa_t *tnfa, int tag)
|
---|
1184 | {
|
---|
1185 | int i;
|
---|
1186 |
|
---|
1187 | for (i = 0; regset[i] >= 0; i++)
|
---|
1188 | {
|
---|
1189 | int id = regset[i] / 2;
|
---|
1190 | int start = !(regset[i] % 2);
|
---|
1191 | if (start)
|
---|
1192 | tnfa->submatch_data[id].so_tag = tag;
|
---|
1193 | else
|
---|
1194 | tnfa->submatch_data[id].eo_tag = tag;
|
---|
1195 | }
|
---|
1196 | regset[0] = -1;
|
---|
1197 | }
|
---|
1198 |
|
---|
1199 |
|
---|
1200 | /* Adds tags to appropriate locations in the parse tree in `tree', so that
|
---|
1201 | subexpressions marked for submatch addressing can be traced. */
|
---|
1202 | static reg_errcode_t
|
---|
1203 | tre_add_tags(tre_mem_t mem, tre_stack_t *stack, tre_ast_node_t *tree,
|
---|
1204 | tre_tnfa_t *tnfa)
|
---|
1205 | {
|
---|
1206 | reg_errcode_t status = REG_OK;
|
---|
1207 | tre_addtags_symbol_t symbol;
|
---|
1208 | tre_ast_node_t *node = tree; /* Tree node we are currently looking at. */
|
---|
1209 | int bottom = tre_stack_num_objects(stack);
|
---|
1210 | /* True for first pass (counting number of needed tags) */
|
---|
1211 | int first_pass = (mem == NULL || tnfa == NULL);
|
---|
1212 | int *regset, *orig_regset;
|
---|
1213 | int num_tags = 0; /* Total number of tags. */
|
---|
1214 | int num_minimals = 0; /* Number of special minimal tags. */
|
---|
1215 | int tag = 0; /* The tag that is to be added next. */
|
---|
1216 | int next_tag = 1; /* Next tag to use after this one. */
|
---|
1217 | int *parents; /* Stack of submatches the current submatch is
|
---|
1218 | contained in. */
|
---|
1219 | int minimal_tag = -1; /* Tag that marks the beginning of a minimal match. */
|
---|
1220 | tre_tag_states_t *saved_states;
|
---|
1221 |
|
---|
1222 | tre_tag_direction_t direction = TRE_TAG_MINIMIZE;
|
---|
1223 | if (!first_pass)
|
---|
1224 | {
|
---|
1225 | tnfa->end_tag = 0;
|
---|
1226 | tnfa->minimal_tags[0] = -1;
|
---|
1227 | }
|
---|
1228 |
|
---|
1229 | regset = xmalloc(sizeof(*regset) * ((tnfa->num_submatches + 1) * 2));
|
---|
1230 | if (regset == NULL)
|
---|
1231 | return REG_ESPACE;
|
---|
1232 | regset[0] = -1;
|
---|
1233 | orig_regset = regset;
|
---|
1234 |
|
---|
1235 | parents = xmalloc(sizeof(*parents) * (tnfa->num_submatches + 1));
|
---|
1236 | if (parents == NULL)
|
---|
1237 | {
|
---|
1238 | xfree(regset);
|
---|
1239 | return REG_ESPACE;
|
---|
1240 | }
|
---|
1241 | parents[0] = -1;
|
---|
1242 |
|
---|
1243 | saved_states = xmalloc(sizeof(*saved_states) * (tnfa->num_submatches + 1));
|
---|
1244 | if (saved_states == NULL)
|
---|
1245 | {
|
---|
1246 | xfree(regset);
|
---|
1247 | xfree(parents);
|
---|
1248 | return REG_ESPACE;
|
---|
1249 | }
|
---|
1250 | else
|
---|
1251 | {
|
---|
1252 | unsigned int i;
|
---|
1253 | for (i = 0; i <= tnfa->num_submatches; i++)
|
---|
1254 | saved_states[i].tag = -1;
|
---|
1255 | }
|
---|
1256 |
|
---|
1257 | STACK_PUSH(stack, voidptr, node);
|
---|
1258 | STACK_PUSH(stack, int, ADDTAGS_RECURSE);
|
---|
1259 |
|
---|
1260 | while (tre_stack_num_objects(stack) > bottom)
|
---|
1261 | {
|
---|
1262 | if (status != REG_OK)
|
---|
1263 | break;
|
---|
1264 |
|
---|
1265 | symbol = (tre_addtags_symbol_t)tre_stack_pop_int(stack);
|
---|
1266 | switch (symbol)
|
---|
1267 | {
|
---|
1268 |
|
---|
1269 | case ADDTAGS_SET_SUBMATCH_END:
|
---|
1270 | {
|
---|
1271 | int id = tre_stack_pop_int(stack);
|
---|
1272 | int i;
|
---|
1273 |
|
---|
1274 | /* Add end of this submatch to regset. */
|
---|
1275 | for (i = 0; regset[i] >= 0; i++);
|
---|
1276 | regset[i] = id * 2 + 1;
|
---|
1277 | regset[i + 1] = -1;
|
---|
1278 |
|
---|
1279 | /* Pop this submatch from the parents stack. */
|
---|
1280 | for (i = 0; parents[i] >= 0; i++);
|
---|
1281 | parents[i - 1] = -1;
|
---|
1282 | break;
|
---|
1283 | }
|
---|
1284 |
|
---|
1285 | case ADDTAGS_RECURSE:
|
---|
1286 | node = tre_stack_pop_voidptr(stack);
|
---|
1287 |
|
---|
1288 | if (node->submatch_id >= 0)
|
---|
1289 | {
|
---|
1290 | int id = node->submatch_id;
|
---|
1291 | int i;
|
---|
1292 |
|
---|
1293 |
|
---|
1294 | /* Add start of this submatch to regset. */
|
---|
1295 | for (i = 0; regset[i] >= 0; i++);
|
---|
1296 | regset[i] = id * 2;
|
---|
1297 | regset[i + 1] = -1;
|
---|
1298 |
|
---|
1299 | if (!first_pass)
|
---|
1300 | {
|
---|
1301 | for (i = 0; parents[i] >= 0; i++);
|
---|
1302 | tnfa->submatch_data[id].parents = NULL;
|
---|
1303 | if (i > 0)
|
---|
1304 | {
|
---|
1305 | int *p = xmalloc(sizeof(*p) * (i + 1));
|
---|
1306 | if (p == NULL)
|
---|
1307 | {
|
---|
1308 | status = REG_ESPACE;
|
---|
1309 | break;
|
---|
1310 | }
|
---|
1311 | assert(tnfa->submatch_data[id].parents == NULL);
|
---|
1312 | tnfa->submatch_data[id].parents = p;
|
---|
1313 | for (i = 0; parents[i] >= 0; i++)
|
---|
1314 | p[i] = parents[i];
|
---|
1315 | p[i] = -1;
|
---|
1316 | }
|
---|
1317 | }
|
---|
1318 |
|
---|
1319 | /* Add end of this submatch to regset after processing this
|
---|
1320 | node. */
|
---|
1321 | STACK_PUSHX(stack, int, node->submatch_id);
|
---|
1322 | STACK_PUSHX(stack, int, ADDTAGS_SET_SUBMATCH_END);
|
---|
1323 | }
|
---|
1324 |
|
---|
1325 | switch (node->type)
|
---|
1326 | {
|
---|
1327 | case LITERAL:
|
---|
1328 | {
|
---|
1329 | tre_literal_t *lit = node->obj;
|
---|
1330 |
|
---|
1331 | if (!IS_SPECIAL(lit) || IS_BACKREF(lit))
|
---|
1332 | {
|
---|
1333 | int i;
|
---|
1334 | if (regset[0] >= 0)
|
---|
1335 | {
|
---|
1336 | /* Regset is not empty, so add a tag before the
|
---|
1337 | literal or backref. */
|
---|
1338 | if (!first_pass)
|
---|
1339 | {
|
---|
1340 | status = tre_add_tag_left(mem, node, tag);
|
---|
1341 | tnfa->tag_directions[tag] = direction;
|
---|
1342 | if (minimal_tag >= 0)
|
---|
1343 | {
|
---|
1344 | for (i = 0; tnfa->minimal_tags[i] >= 0; i++);
|
---|
1345 | tnfa->minimal_tags[i] = tag;
|
---|
1346 | tnfa->minimal_tags[i + 1] = minimal_tag;
|
---|
1347 | tnfa->minimal_tags[i + 2] = -1;
|
---|
1348 | minimal_tag = -1;
|
---|
1349 | num_minimals++;
|
---|
1350 | }
|
---|
1351 | tre_purge_regset(regset, tnfa, tag);
|
---|
1352 | }
|
---|
1353 | else
|
---|
1354 | {
|
---|
1355 | node->num_tags = 1;
|
---|
1356 | }
|
---|
1357 |
|
---|
1358 | regset[0] = -1;
|
---|
1359 | tag = next_tag;
|
---|
1360 | num_tags++;
|
---|
1361 | next_tag++;
|
---|
1362 | }
|
---|
1363 | }
|
---|
1364 | else
|
---|
1365 | {
|
---|
1366 | assert(!IS_TAG(lit));
|
---|
1367 | }
|
---|
1368 | break;
|
---|
1369 | }
|
---|
1370 | case CATENATION:
|
---|
1371 | {
|
---|
1372 | tre_catenation_t *cat = node->obj;
|
---|
1373 | tre_ast_node_t *left = cat->left;
|
---|
1374 | tre_ast_node_t *right = cat->right;
|
---|
1375 | int reserved_tag = -1;
|
---|
1376 |
|
---|
1377 |
|
---|
1378 | /* After processing right child. */
|
---|
1379 | STACK_PUSHX(stack, voidptr, node);
|
---|
1380 | STACK_PUSHX(stack, int, ADDTAGS_AFTER_CAT_RIGHT);
|
---|
1381 |
|
---|
1382 | /* Process right child. */
|
---|
1383 | STACK_PUSHX(stack, voidptr, right);
|
---|
1384 | STACK_PUSHX(stack, int, ADDTAGS_RECURSE);
|
---|
1385 |
|
---|
1386 | /* After processing left child. */
|
---|
1387 | STACK_PUSHX(stack, int, next_tag + left->num_tags);
|
---|
1388 | if (left->num_tags > 0 && right->num_tags > 0)
|
---|
1389 | {
|
---|
1390 | /* Reserve the next tag to the right child. */
|
---|
1391 | reserved_tag = next_tag;
|
---|
1392 | next_tag++;
|
---|
1393 | }
|
---|
1394 | STACK_PUSHX(stack, int, reserved_tag);
|
---|
1395 | STACK_PUSHX(stack, int, ADDTAGS_AFTER_CAT_LEFT);
|
---|
1396 |
|
---|
1397 | /* Process left child. */
|
---|
1398 | STACK_PUSHX(stack, voidptr, left);
|
---|
1399 | STACK_PUSHX(stack, int, ADDTAGS_RECURSE);
|
---|
1400 |
|
---|
1401 | }
|
---|
1402 | break;
|
---|
1403 | case ITERATION:
|
---|
1404 | {
|
---|
1405 | tre_iteration_t *iter = node->obj;
|
---|
1406 |
|
---|
1407 | if (first_pass)
|
---|
1408 | {
|
---|
1409 | STACK_PUSHX(stack, int, regset[0] >= 0 || iter->minimal);
|
---|
1410 | }
|
---|
1411 | else
|
---|
1412 | {
|
---|
1413 | STACK_PUSHX(stack, int, tag);
|
---|
1414 | STACK_PUSHX(stack, int, iter->minimal);
|
---|
1415 | }
|
---|
1416 | STACK_PUSHX(stack, voidptr, node);
|
---|
1417 | STACK_PUSHX(stack, int, ADDTAGS_AFTER_ITERATION);
|
---|
1418 |
|
---|
1419 | STACK_PUSHX(stack, voidptr, iter->arg);
|
---|
1420 | STACK_PUSHX(stack, int, ADDTAGS_RECURSE);
|
---|
1421 |
|
---|
1422 | /* Regset is not empty, so add a tag here. */
|
---|
1423 | if (regset[0] >= 0 || iter->minimal)
|
---|
1424 | {
|
---|
1425 | if (!first_pass)
|
---|
1426 | {
|
---|
1427 | int i;
|
---|
1428 | status = tre_add_tag_left(mem, node, tag);
|
---|
1429 | if (iter->minimal)
|
---|
1430 | tnfa->tag_directions[tag] = TRE_TAG_MAXIMIZE;
|
---|
1431 | else
|
---|
1432 | tnfa->tag_directions[tag] = direction;
|
---|
1433 | if (minimal_tag >= 0)
|
---|
1434 | {
|
---|
1435 | for (i = 0; tnfa->minimal_tags[i] >= 0; i++);
|
---|
1436 | tnfa->minimal_tags[i] = tag;
|
---|
1437 | tnfa->minimal_tags[i + 1] = minimal_tag;
|
---|
1438 | tnfa->minimal_tags[i + 2] = -1;
|
---|
1439 | minimal_tag = -1;
|
---|
1440 | num_minimals++;
|
---|
1441 | }
|
---|
1442 | tre_purge_regset(regset, tnfa, tag);
|
---|
1443 | }
|
---|
1444 |
|
---|
1445 | regset[0] = -1;
|
---|
1446 | tag = next_tag;
|
---|
1447 | num_tags++;
|
---|
1448 | next_tag++;
|
---|
1449 | }
|
---|
1450 | direction = TRE_TAG_MINIMIZE;
|
---|
1451 | }
|
---|
1452 | break;
|
---|
1453 | case UNION:
|
---|
1454 | {
|
---|
1455 | tre_union_t *uni = node->obj;
|
---|
1456 | tre_ast_node_t *left = uni->left;
|
---|
1457 | tre_ast_node_t *right = uni->right;
|
---|
1458 | int left_tag;
|
---|
1459 | int right_tag;
|
---|
1460 |
|
---|
1461 | if (regset[0] >= 0)
|
---|
1462 | {
|
---|
1463 | left_tag = next_tag;
|
---|
1464 | right_tag = next_tag + 1;
|
---|
1465 | }
|
---|
1466 | else
|
---|
1467 | {
|
---|
1468 | left_tag = tag;
|
---|
1469 | right_tag = next_tag;
|
---|
1470 | }
|
---|
1471 |
|
---|
1472 | /* After processing right child. */
|
---|
1473 | STACK_PUSHX(stack, int, right_tag);
|
---|
1474 | STACK_PUSHX(stack, int, left_tag);
|
---|
1475 | STACK_PUSHX(stack, voidptr, regset);
|
---|
1476 | STACK_PUSHX(stack, int, regset[0] >= 0);
|
---|
1477 | STACK_PUSHX(stack, voidptr, node);
|
---|
1478 | STACK_PUSHX(stack, voidptr, right);
|
---|
1479 | STACK_PUSHX(stack, voidptr, left);
|
---|
1480 | STACK_PUSHX(stack, int, ADDTAGS_AFTER_UNION_RIGHT);
|
---|
1481 |
|
---|
1482 | /* Process right child. */
|
---|
1483 | STACK_PUSHX(stack, voidptr, right);
|
---|
1484 | STACK_PUSHX(stack, int, ADDTAGS_RECURSE);
|
---|
1485 |
|
---|
1486 | /* After processing left child. */
|
---|
1487 | STACK_PUSHX(stack, int, ADDTAGS_AFTER_UNION_LEFT);
|
---|
1488 |
|
---|
1489 | /* Process left child. */
|
---|
1490 | STACK_PUSHX(stack, voidptr, left);
|
---|
1491 | STACK_PUSHX(stack, int, ADDTAGS_RECURSE);
|
---|
1492 |
|
---|
1493 | /* Regset is not empty, so add a tag here. */
|
---|
1494 | if (regset[0] >= 0)
|
---|
1495 | {
|
---|
1496 | if (!first_pass)
|
---|
1497 | {
|
---|
1498 | int i;
|
---|
1499 | status = tre_add_tag_left(mem, node, tag);
|
---|
1500 | tnfa->tag_directions[tag] = direction;
|
---|
1501 | if (minimal_tag >= 0)
|
---|
1502 | {
|
---|
1503 | for (i = 0; tnfa->minimal_tags[i] >= 0; i++);
|
---|
1504 | tnfa->minimal_tags[i] = tag;
|
---|
1505 | tnfa->minimal_tags[i + 1] = minimal_tag;
|
---|
1506 | tnfa->minimal_tags[i + 2] = -1;
|
---|
1507 | minimal_tag = -1;
|
---|
1508 | num_minimals++;
|
---|
1509 | }
|
---|
1510 | tre_purge_regset(regset, tnfa, tag);
|
---|
1511 | }
|
---|
1512 |
|
---|
1513 | regset[0] = -1;
|
---|
1514 | tag = next_tag;
|
---|
1515 | num_tags++;
|
---|
1516 | next_tag++;
|
---|
1517 | }
|
---|
1518 |
|
---|
1519 | if (node->num_submatches > 0)
|
---|
1520 | {
|
---|
1521 | /* The next two tags are reserved for markers. */
|
---|
1522 | next_tag++;
|
---|
1523 | tag = next_tag;
|
---|
1524 | next_tag++;
|
---|
1525 | }
|
---|
1526 |
|
---|
1527 | break;
|
---|
1528 | }
|
---|
1529 | }
|
---|
1530 |
|
---|
1531 | if (node->submatch_id >= 0)
|
---|
1532 | {
|
---|
1533 | int i;
|
---|
1534 | /* Push this submatch on the parents stack. */
|
---|
1535 | for (i = 0; parents[i] >= 0; i++);
|
---|
1536 | parents[i] = node->submatch_id;
|
---|
1537 | parents[i + 1] = -1;
|
---|
1538 | }
|
---|
1539 |
|
---|
1540 | break; /* end case: ADDTAGS_RECURSE */
|
---|
1541 |
|
---|
1542 | case ADDTAGS_AFTER_ITERATION:
|
---|
1543 | {
|
---|
1544 | int minimal = 0;
|
---|
1545 | int enter_tag;
|
---|
1546 | node = tre_stack_pop_voidptr(stack);
|
---|
1547 | if (first_pass)
|
---|
1548 | {
|
---|
1549 | node->num_tags = ((tre_iteration_t *)node->obj)->arg->num_tags
|
---|
1550 | + tre_stack_pop_int(stack);
|
---|
1551 | minimal_tag = -1;
|
---|
1552 | }
|
---|
1553 | else
|
---|
1554 | {
|
---|
1555 | minimal = tre_stack_pop_int(stack);
|
---|
1556 | enter_tag = tre_stack_pop_int(stack);
|
---|
1557 | if (minimal)
|
---|
1558 | minimal_tag = enter_tag;
|
---|
1559 | }
|
---|
1560 |
|
---|
1561 | if (!first_pass)
|
---|
1562 | {
|
---|
1563 | if (minimal)
|
---|
1564 | direction = TRE_TAG_MINIMIZE;
|
---|
1565 | else
|
---|
1566 | direction = TRE_TAG_MAXIMIZE;
|
---|
1567 | }
|
---|
1568 | break;
|
---|
1569 | }
|
---|
1570 |
|
---|
1571 | case ADDTAGS_AFTER_CAT_LEFT:
|
---|
1572 | {
|
---|
1573 | int new_tag = tre_stack_pop_int(stack);
|
---|
1574 | next_tag = tre_stack_pop_int(stack);
|
---|
1575 | if (new_tag >= 0)
|
---|
1576 | {
|
---|
1577 | tag = new_tag;
|
---|
1578 | }
|
---|
1579 | break;
|
---|
1580 | }
|
---|
1581 |
|
---|
1582 | case ADDTAGS_AFTER_CAT_RIGHT:
|
---|
1583 | node = tre_stack_pop_voidptr(stack);
|
---|
1584 | if (first_pass)
|
---|
1585 | node->num_tags = ((tre_catenation_t *)node->obj)->left->num_tags
|
---|
1586 | + ((tre_catenation_t *)node->obj)->right->num_tags;
|
---|
1587 | break;
|
---|
1588 |
|
---|
1589 | case ADDTAGS_AFTER_UNION_LEFT:
|
---|
1590 | /* Lift the bottom of the `regset' array so that when processing
|
---|
1591 | the right operand the items currently in the array are
|
---|
1592 | invisible. The original bottom was saved at ADDTAGS_UNION and
|
---|
1593 | will be restored at ADDTAGS_AFTER_UNION_RIGHT below. */
|
---|
1594 | while (*regset >= 0)
|
---|
1595 | regset++;
|
---|
1596 | break;
|
---|
1597 |
|
---|
1598 | case ADDTAGS_AFTER_UNION_RIGHT:
|
---|
1599 | {
|
---|
1600 | int added_tags, tag_left, tag_right;
|
---|
1601 | tre_ast_node_t *left = tre_stack_pop_voidptr(stack);
|
---|
1602 | tre_ast_node_t *right = tre_stack_pop_voidptr(stack);
|
---|
1603 | node = tre_stack_pop_voidptr(stack);
|
---|
1604 | added_tags = tre_stack_pop_int(stack);
|
---|
1605 | if (first_pass)
|
---|
1606 | {
|
---|
1607 | node->num_tags = ((tre_union_t *)node->obj)->left->num_tags
|
---|
1608 | + ((tre_union_t *)node->obj)->right->num_tags + added_tags
|
---|
1609 | + ((node->num_submatches > 0) ? 2 : 0);
|
---|
1610 | }
|
---|
1611 | regset = tre_stack_pop_voidptr(stack);
|
---|
1612 | tag_left = tre_stack_pop_int(stack);
|
---|
1613 | tag_right = tre_stack_pop_int(stack);
|
---|
1614 |
|
---|
1615 | /* Add tags after both children, the left child gets a smaller
|
---|
1616 | tag than the right child. This guarantees that we prefer
|
---|
1617 | the left child over the right child. */
|
---|
1618 | /* XXX - This is not always necessary (if the children have
|
---|
1619 | tags which must be seen for every match of that child). */
|
---|
1620 | /* XXX - Check if this is the only place where tre_add_tag_right
|
---|
1621 | is used. If so, use tre_add_tag_left (putting the tag before
|
---|
1622 | the child as opposed after the child) and throw away
|
---|
1623 | tre_add_tag_right. */
|
---|
1624 | if (node->num_submatches > 0)
|
---|
1625 | {
|
---|
1626 | if (!first_pass)
|
---|
1627 | {
|
---|
1628 | status = tre_add_tag_right(mem, left, tag_left);
|
---|
1629 | tnfa->tag_directions[tag_left] = TRE_TAG_MAXIMIZE;
|
---|
1630 | if (status == REG_OK)
|
---|
1631 | status = tre_add_tag_right(mem, right, tag_right);
|
---|
1632 | tnfa->tag_directions[tag_right] = TRE_TAG_MAXIMIZE;
|
---|
1633 | }
|
---|
1634 | num_tags += 2;
|
---|
1635 | }
|
---|
1636 | direction = TRE_TAG_MAXIMIZE;
|
---|
1637 | break;
|
---|
1638 | }
|
---|
1639 |
|
---|
1640 | default:
|
---|
1641 | assert(0);
|
---|
1642 | break;
|
---|
1643 |
|
---|
1644 | } /* end switch(symbol) */
|
---|
1645 | } /* end while(tre_stack_num_objects(stack) > bottom) */
|
---|
1646 |
|
---|
1647 | if (!first_pass)
|
---|
1648 | tre_purge_regset(regset, tnfa, tag);
|
---|
1649 |
|
---|
1650 | if (!first_pass && minimal_tag >= 0)
|
---|
1651 | {
|
---|
1652 | int i;
|
---|
1653 | for (i = 0; tnfa->minimal_tags[i] >= 0; i++);
|
---|
1654 | tnfa->minimal_tags[i] = tag;
|
---|
1655 | tnfa->minimal_tags[i + 1] = minimal_tag;
|
---|
1656 | tnfa->minimal_tags[i + 2] = -1;
|
---|
1657 | minimal_tag = -1;
|
---|
1658 | num_minimals++;
|
---|
1659 | }
|
---|
1660 |
|
---|
1661 | assert(tree->num_tags == num_tags);
|
---|
1662 | tnfa->end_tag = num_tags;
|
---|
1663 | tnfa->num_tags = num_tags;
|
---|
1664 | tnfa->num_minimals = num_minimals;
|
---|
1665 | xfree(orig_regset);
|
---|
1666 | xfree(parents);
|
---|
1667 | xfree(saved_states);
|
---|
1668 | return status;
|
---|
1669 | }
|
---|
1670 |
|
---|
1671 |
|
---|
1672 |
|
---|
1673 | /*
|
---|
1674 | AST to TNFA compilation routines.
|
---|
1675 | */
|
---|
1676 |
|
---|
1677 | typedef enum {
|
---|
1678 | COPY_RECURSE,
|
---|
1679 | COPY_SET_RESULT_PTR
|
---|
1680 | } tre_copyast_symbol_t;
|
---|
1681 |
|
---|
1682 | /* Flags for tre_copy_ast(). */
|
---|
1683 | #define COPY_REMOVE_TAGS 1
|
---|
1684 | #define COPY_MAXIMIZE_FIRST_TAG 2
|
---|
1685 |
|
---|
1686 | static reg_errcode_t
|
---|
1687 | tre_copy_ast(tre_mem_t mem, tre_stack_t *stack, tre_ast_node_t *ast,
|
---|
1688 | int flags, int *pos_add, tre_tag_direction_t *tag_directions,
|
---|
1689 | tre_ast_node_t **copy, int *max_pos)
|
---|
1690 | {
|
---|
1691 | reg_errcode_t status = REG_OK;
|
---|
1692 | int bottom = tre_stack_num_objects(stack);
|
---|
1693 | int num_copied = 0;
|
---|
1694 | int first_tag = 1;
|
---|
1695 | tre_ast_node_t **result = copy;
|
---|
1696 | tre_copyast_symbol_t symbol;
|
---|
1697 |
|
---|
1698 | STACK_PUSH(stack, voidptr, ast);
|
---|
1699 | STACK_PUSH(stack, int, COPY_RECURSE);
|
---|
1700 |
|
---|
1701 | while (status == REG_OK && tre_stack_num_objects(stack) > bottom)
|
---|
1702 | {
|
---|
1703 | tre_ast_node_t *node;
|
---|
1704 | if (status != REG_OK)
|
---|
1705 | break;
|
---|
1706 |
|
---|
1707 | symbol = (tre_copyast_symbol_t)tre_stack_pop_int(stack);
|
---|
1708 | switch (symbol)
|
---|
1709 | {
|
---|
1710 | case COPY_SET_RESULT_PTR:
|
---|
1711 | result = tre_stack_pop_voidptr(stack);
|
---|
1712 | break;
|
---|
1713 | case COPY_RECURSE:
|
---|
1714 | node = tre_stack_pop_voidptr(stack);
|
---|
1715 | switch (node->type)
|
---|
1716 | {
|
---|
1717 | case LITERAL:
|
---|
1718 | {
|
---|
1719 | tre_literal_t *lit = node->obj;
|
---|
1720 | int pos = lit->position;
|
---|
1721 | int min = lit->code_min;
|
---|
1722 | int max = lit->code_max;
|
---|
1723 | if (!IS_SPECIAL(lit) || IS_BACKREF(lit))
|
---|
1724 | {
|
---|
1725 | /* XXX - e.g. [ab] has only one position but two
|
---|
1726 | nodes, so we are creating holes in the state space
|
---|
1727 | here. Not fatal, just wastes memory. */
|
---|
1728 | pos += *pos_add;
|
---|
1729 | num_copied++;
|
---|
1730 | }
|
---|
1731 | else if (IS_TAG(lit) && (flags & COPY_REMOVE_TAGS))
|
---|
1732 | {
|
---|
1733 | /* Change this tag to empty. */
|
---|
1734 | min = EMPTY;
|
---|
1735 | max = pos = -1;
|
---|
1736 | }
|
---|
1737 | else if (IS_TAG(lit) && (flags & COPY_MAXIMIZE_FIRST_TAG)
|
---|
1738 | && first_tag)
|
---|
1739 | {
|
---|
1740 | /* Maximize the first tag. */
|
---|
1741 | tag_directions[max] = TRE_TAG_MAXIMIZE;
|
---|
1742 | first_tag = 0;
|
---|
1743 | }
|
---|
1744 | *result = tre_ast_new_literal(mem, min, max, pos);
|
---|
1745 | if (*result == NULL)
|
---|
1746 | status = REG_ESPACE;
|
---|
1747 | else {
|
---|
1748 | tre_literal_t *p = (*result)->obj;
|
---|
1749 | p->class = lit->class;
|
---|
1750 | p->neg_classes = lit->neg_classes;
|
---|
1751 | }
|
---|
1752 |
|
---|
1753 | if (pos > *max_pos)
|
---|
1754 | *max_pos = pos;
|
---|
1755 | break;
|
---|
1756 | }
|
---|
1757 | case UNION:
|
---|
1758 | {
|
---|
1759 | tre_union_t *uni = node->obj;
|
---|
1760 | tre_union_t *tmp;
|
---|
1761 | *result = tre_ast_new_union(mem, uni->left, uni->right);
|
---|
1762 | if (*result == NULL)
|
---|
1763 | {
|
---|
1764 | status = REG_ESPACE;
|
---|
1765 | break;
|
---|
1766 | }
|
---|
1767 | tmp = (*result)->obj;
|
---|
1768 | result = &tmp->left;
|
---|
1769 | STACK_PUSHX(stack, voidptr, uni->right);
|
---|
1770 | STACK_PUSHX(stack, int, COPY_RECURSE);
|
---|
1771 | STACK_PUSHX(stack, voidptr, &tmp->right);
|
---|
1772 | STACK_PUSHX(stack, int, COPY_SET_RESULT_PTR);
|
---|
1773 | STACK_PUSHX(stack, voidptr, uni->left);
|
---|
1774 | STACK_PUSHX(stack, int, COPY_RECURSE);
|
---|
1775 | break;
|
---|
1776 | }
|
---|
1777 | case CATENATION:
|
---|
1778 | {
|
---|
1779 | tre_catenation_t *cat = node->obj;
|
---|
1780 | tre_catenation_t *tmp;
|
---|
1781 | *result = tre_ast_new_catenation(mem, cat->left, cat->right);
|
---|
1782 | if (*result == NULL)
|
---|
1783 | {
|
---|
1784 | status = REG_ESPACE;
|
---|
1785 | break;
|
---|
1786 | }
|
---|
1787 | tmp = (*result)->obj;
|
---|
1788 | tmp->left = NULL;
|
---|
1789 | tmp->right = NULL;
|
---|
1790 | result = &tmp->left;
|
---|
1791 |
|
---|
1792 | STACK_PUSHX(stack, voidptr, cat->right);
|
---|
1793 | STACK_PUSHX(stack, int, COPY_RECURSE);
|
---|
1794 | STACK_PUSHX(stack, voidptr, &tmp->right);
|
---|
1795 | STACK_PUSHX(stack, int, COPY_SET_RESULT_PTR);
|
---|
1796 | STACK_PUSHX(stack, voidptr, cat->left);
|
---|
1797 | STACK_PUSHX(stack, int, COPY_RECURSE);
|
---|
1798 | break;
|
---|
1799 | }
|
---|
1800 | case ITERATION:
|
---|
1801 | {
|
---|
1802 | tre_iteration_t *iter = node->obj;
|
---|
1803 | STACK_PUSHX(stack, voidptr, iter->arg);
|
---|
1804 | STACK_PUSHX(stack, int, COPY_RECURSE);
|
---|
1805 | *result = tre_ast_new_iter(mem, iter->arg, iter->min,
|
---|
1806 | iter->max, iter->minimal);
|
---|
1807 | if (*result == NULL)
|
---|
1808 | {
|
---|
1809 | status = REG_ESPACE;
|
---|
1810 | break;
|
---|
1811 | }
|
---|
1812 | iter = (*result)->obj;
|
---|
1813 | result = &iter->arg;
|
---|
1814 | break;
|
---|
1815 | }
|
---|
1816 | default:
|
---|
1817 | assert(0);
|
---|
1818 | break;
|
---|
1819 | }
|
---|
1820 | break;
|
---|
1821 | }
|
---|
1822 | }
|
---|
1823 | *pos_add += num_copied;
|
---|
1824 | return status;
|
---|
1825 | }
|
---|
1826 |
|
---|
1827 | typedef enum {
|
---|
1828 | EXPAND_RECURSE,
|
---|
1829 | EXPAND_AFTER_ITER
|
---|
1830 | } tre_expand_ast_symbol_t;
|
---|
1831 |
|
---|
1832 | /* Expands each iteration node that has a finite nonzero minimum or maximum
|
---|
1833 | iteration count to a catenated sequence of copies of the node. */
|
---|
1834 | static reg_errcode_t
|
---|
1835 | tre_expand_ast(tre_mem_t mem, tre_stack_t *stack, tre_ast_node_t *ast,
|
---|
1836 | int *position, tre_tag_direction_t *tag_directions)
|
---|
1837 | {
|
---|
1838 | reg_errcode_t status = REG_OK;
|
---|
1839 | int bottom = tre_stack_num_objects(stack);
|
---|
1840 | int pos_add = 0;
|
---|
1841 | int pos_add_total = 0;
|
---|
1842 | int max_pos = 0;
|
---|
1843 | int iter_depth = 0;
|
---|
1844 |
|
---|
1845 | STACK_PUSHR(stack, voidptr, ast);
|
---|
1846 | STACK_PUSHR(stack, int, EXPAND_RECURSE);
|
---|
1847 | while (status == REG_OK && tre_stack_num_objects(stack) > bottom)
|
---|
1848 | {
|
---|
1849 | tre_ast_node_t *node;
|
---|
1850 | tre_expand_ast_symbol_t symbol;
|
---|
1851 |
|
---|
1852 | if (status != REG_OK)
|
---|
1853 | break;
|
---|
1854 |
|
---|
1855 | symbol = (tre_expand_ast_symbol_t)tre_stack_pop_int(stack);
|
---|
1856 | node = tre_stack_pop_voidptr(stack);
|
---|
1857 | switch (symbol)
|
---|
1858 | {
|
---|
1859 | case EXPAND_RECURSE:
|
---|
1860 | switch (node->type)
|
---|
1861 | {
|
---|
1862 | case LITERAL:
|
---|
1863 | {
|
---|
1864 | tre_literal_t *lit= node->obj;
|
---|
1865 | if (!IS_SPECIAL(lit) || IS_BACKREF(lit))
|
---|
1866 | {
|
---|
1867 | lit->position += pos_add;
|
---|
1868 | if (lit->position > max_pos)
|
---|
1869 | max_pos = lit->position;
|
---|
1870 | }
|
---|
1871 | break;
|
---|
1872 | }
|
---|
1873 | case UNION:
|
---|
1874 | {
|
---|
1875 | tre_union_t *uni = node->obj;
|
---|
1876 | STACK_PUSHX(stack, voidptr, uni->right);
|
---|
1877 | STACK_PUSHX(stack, int, EXPAND_RECURSE);
|
---|
1878 | STACK_PUSHX(stack, voidptr, uni->left);
|
---|
1879 | STACK_PUSHX(stack, int, EXPAND_RECURSE);
|
---|
1880 | break;
|
---|
1881 | }
|
---|
1882 | case CATENATION:
|
---|
1883 | {
|
---|
1884 | tre_catenation_t *cat = node->obj;
|
---|
1885 | STACK_PUSHX(stack, voidptr, cat->right);
|
---|
1886 | STACK_PUSHX(stack, int, EXPAND_RECURSE);
|
---|
1887 | STACK_PUSHX(stack, voidptr, cat->left);
|
---|
1888 | STACK_PUSHX(stack, int, EXPAND_RECURSE);
|
---|
1889 | break;
|
---|
1890 | }
|
---|
1891 | case ITERATION:
|
---|
1892 | {
|
---|
1893 | tre_iteration_t *iter = node->obj;
|
---|
1894 | STACK_PUSHX(stack, int, pos_add);
|
---|
1895 | STACK_PUSHX(stack, voidptr, node);
|
---|
1896 | STACK_PUSHX(stack, int, EXPAND_AFTER_ITER);
|
---|
1897 | STACK_PUSHX(stack, voidptr, iter->arg);
|
---|
1898 | STACK_PUSHX(stack, int, EXPAND_RECURSE);
|
---|
1899 | /* If we are going to expand this node at EXPAND_AFTER_ITER
|
---|
1900 | then don't increase the `pos' fields of the nodes now, it
|
---|
1901 | will get done when expanding. */
|
---|
1902 | if (iter->min > 1 || iter->max > 1)
|
---|
1903 | pos_add = 0;
|
---|
1904 | iter_depth++;
|
---|
1905 | break;
|
---|
1906 | }
|
---|
1907 | default:
|
---|
1908 | assert(0);
|
---|
1909 | break;
|
---|
1910 | }
|
---|
1911 | break;
|
---|
1912 | case EXPAND_AFTER_ITER:
|
---|
1913 | {
|
---|
1914 | tre_iteration_t *iter = node->obj;
|
---|
1915 | int pos_add_last;
|
---|
1916 | pos_add = tre_stack_pop_int(stack);
|
---|
1917 | pos_add_last = pos_add;
|
---|
1918 | if (iter->min > 1 || iter->max > 1)
|
---|
1919 | {
|
---|
1920 | tre_ast_node_t *seq1 = NULL, *seq2 = NULL;
|
---|
1921 | int j;
|
---|
1922 | int pos_add_save = pos_add;
|
---|
1923 |
|
---|
1924 | /* Create a catenated sequence of copies of the node. */
|
---|
1925 | for (j = 0; j < iter->min; j++)
|
---|
1926 | {
|
---|
1927 | tre_ast_node_t *copy;
|
---|
1928 | /* Remove tags from all but the last copy. */
|
---|
1929 | int flags = ((j + 1 < iter->min)
|
---|
1930 | ? COPY_REMOVE_TAGS
|
---|
1931 | : COPY_MAXIMIZE_FIRST_TAG);
|
---|
1932 | pos_add_save = pos_add;
|
---|
1933 | status = tre_copy_ast(mem, stack, iter->arg, flags,
|
---|
1934 | &pos_add, tag_directions, ©,
|
---|
1935 | &max_pos);
|
---|
1936 | if (status != REG_OK)
|
---|
1937 | return status;
|
---|
1938 | if (seq1 != NULL)
|
---|
1939 | seq1 = tre_ast_new_catenation(mem, seq1, copy);
|
---|
1940 | else
|
---|
1941 | seq1 = copy;
|
---|
1942 | if (seq1 == NULL)
|
---|
1943 | return REG_ESPACE;
|
---|
1944 | }
|
---|
1945 |
|
---|
1946 | if (iter->max == -1)
|
---|
1947 | {
|
---|
1948 | /* No upper limit. */
|
---|
1949 | pos_add_save = pos_add;
|
---|
1950 | status = tre_copy_ast(mem, stack, iter->arg, 0,
|
---|
1951 | &pos_add, NULL, &seq2, &max_pos);
|
---|
1952 | if (status != REG_OK)
|
---|
1953 | return status;
|
---|
1954 | seq2 = tre_ast_new_iter(mem, seq2, 0, -1, 0);
|
---|
1955 | if (seq2 == NULL)
|
---|
1956 | return REG_ESPACE;
|
---|
1957 | }
|
---|
1958 | else
|
---|
1959 | {
|
---|
1960 | for (j = iter->min; j < iter->max; j++)
|
---|
1961 | {
|
---|
1962 | tre_ast_node_t *tmp, *copy;
|
---|
1963 | pos_add_save = pos_add;
|
---|
1964 | status = tre_copy_ast(mem, stack, iter->arg, 0,
|
---|
1965 | &pos_add, NULL, ©, &max_pos);
|
---|
1966 | if (status != REG_OK)
|
---|
1967 | return status;
|
---|
1968 | if (seq2 != NULL)
|
---|
1969 | seq2 = tre_ast_new_catenation(mem, copy, seq2);
|
---|
1970 | else
|
---|
1971 | seq2 = copy;
|
---|
1972 | if (seq2 == NULL)
|
---|
1973 | return REG_ESPACE;
|
---|
1974 | tmp = tre_ast_new_literal(mem, EMPTY, -1, -1);
|
---|
1975 | if (tmp == NULL)
|
---|
1976 | return REG_ESPACE;
|
---|
1977 | seq2 = tre_ast_new_union(mem, tmp, seq2);
|
---|
1978 | if (seq2 == NULL)
|
---|
1979 | return REG_ESPACE;
|
---|
1980 | }
|
---|
1981 | }
|
---|
1982 |
|
---|
1983 | pos_add = pos_add_save;
|
---|
1984 | if (seq1 == NULL)
|
---|
1985 | seq1 = seq2;
|
---|
1986 | else if (seq2 != NULL)
|
---|
1987 | seq1 = tre_ast_new_catenation(mem, seq1, seq2);
|
---|
1988 | if (seq1 == NULL)
|
---|
1989 | return REG_ESPACE;
|
---|
1990 | node->obj = seq1->obj;
|
---|
1991 | node->type = seq1->type;
|
---|
1992 | }
|
---|
1993 |
|
---|
1994 | iter_depth--;
|
---|
1995 | pos_add_total += pos_add - pos_add_last;
|
---|
1996 | if (iter_depth == 0)
|
---|
1997 | pos_add = pos_add_total;
|
---|
1998 |
|
---|
1999 | break;
|
---|
2000 | }
|
---|
2001 | default:
|
---|
2002 | assert(0);
|
---|
2003 | break;
|
---|
2004 | }
|
---|
2005 | }
|
---|
2006 |
|
---|
2007 | *position += pos_add_total;
|
---|
2008 |
|
---|
2009 | /* `max_pos' should never be larger than `*position' if the above
|
---|
2010 | code works, but just an extra safeguard let's make sure
|
---|
2011 | `*position' is set large enough so enough memory will be
|
---|
2012 | allocated for the transition table. */
|
---|
2013 | if (max_pos > *position)
|
---|
2014 | *position = max_pos;
|
---|
2015 |
|
---|
2016 | return status;
|
---|
2017 | }
|
---|
2018 |
|
---|
2019 | static tre_pos_and_tags_t *
|
---|
2020 | tre_set_empty(tre_mem_t mem)
|
---|
2021 | {
|
---|
2022 | tre_pos_and_tags_t *new_set;
|
---|
2023 |
|
---|
2024 | new_set = tre_mem_calloc(mem, sizeof(*new_set));
|
---|
2025 | if (new_set == NULL)
|
---|
2026 | return NULL;
|
---|
2027 |
|
---|
2028 | new_set[0].position = -1;
|
---|
2029 | new_set[0].code_min = -1;
|
---|
2030 | new_set[0].code_max = -1;
|
---|
2031 |
|
---|
2032 | return new_set;
|
---|
2033 | }
|
---|
2034 |
|
---|
2035 | static tre_pos_and_tags_t *
|
---|
2036 | tre_set_one(tre_mem_t mem, int position, int code_min, int code_max,
|
---|
2037 | tre_ctype_t class, tre_ctype_t *neg_classes, int backref)
|
---|
2038 | {
|
---|
2039 | tre_pos_and_tags_t *new_set;
|
---|
2040 |
|
---|
2041 | new_set = tre_mem_calloc(mem, sizeof(*new_set) * 2);
|
---|
2042 | if (new_set == NULL)
|
---|
2043 | return NULL;
|
---|
2044 |
|
---|
2045 | new_set[0].position = position;
|
---|
2046 | new_set[0].code_min = code_min;
|
---|
2047 | new_set[0].code_max = code_max;
|
---|
2048 | new_set[0].class = class;
|
---|
2049 | new_set[0].neg_classes = neg_classes;
|
---|
2050 | new_set[0].backref = backref;
|
---|
2051 | new_set[1].position = -1;
|
---|
2052 | new_set[1].code_min = -1;
|
---|
2053 | new_set[1].code_max = -1;
|
---|
2054 |
|
---|
2055 | return new_set;
|
---|
2056 | }
|
---|
2057 |
|
---|
2058 | static tre_pos_and_tags_t *
|
---|
2059 | tre_set_union(tre_mem_t mem, tre_pos_and_tags_t *set1, tre_pos_and_tags_t *set2,
|
---|
2060 | int *tags, int assertions)
|
---|
2061 | {
|
---|
2062 | int s1, s2, i, j;
|
---|
2063 | tre_pos_and_tags_t *new_set;
|
---|
2064 | int *new_tags;
|
---|
2065 | int num_tags;
|
---|
2066 |
|
---|
2067 | for (num_tags = 0; tags != NULL && tags[num_tags] >= 0; num_tags++);
|
---|
2068 | for (s1 = 0; set1[s1].position >= 0; s1++);
|
---|
2069 | for (s2 = 0; set2[s2].position >= 0; s2++);
|
---|
2070 | new_set = tre_mem_calloc(mem, sizeof(*new_set) * (s1 + s2 + 1));
|
---|
2071 | if (!new_set )
|
---|
2072 | return NULL;
|
---|
2073 |
|
---|
2074 | for (s1 = 0; set1[s1].position >= 0; s1++)
|
---|
2075 | {
|
---|
2076 | new_set[s1].position = set1[s1].position;
|
---|
2077 | new_set[s1].code_min = set1[s1].code_min;
|
---|
2078 | new_set[s1].code_max = set1[s1].code_max;
|
---|
2079 | new_set[s1].assertions = set1[s1].assertions | assertions;
|
---|
2080 | new_set[s1].class = set1[s1].class;
|
---|
2081 | new_set[s1].neg_classes = set1[s1].neg_classes;
|
---|
2082 | new_set[s1].backref = set1[s1].backref;
|
---|
2083 | if (set1[s1].tags == NULL && tags == NULL)
|
---|
2084 | new_set[s1].tags = NULL;
|
---|
2085 | else
|
---|
2086 | {
|
---|
2087 | for (i = 0; set1[s1].tags != NULL && set1[s1].tags[i] >= 0; i++);
|
---|
2088 | new_tags = tre_mem_alloc(mem, (sizeof(*new_tags)
|
---|
2089 | * (i + num_tags + 1)));
|
---|
2090 | if (new_tags == NULL)
|
---|
2091 | return NULL;
|
---|
2092 | for (j = 0; j < i; j++)
|
---|
2093 | new_tags[j] = set1[s1].tags[j];
|
---|
2094 | for (i = 0; i < num_tags; i++)
|
---|
2095 | new_tags[j + i] = tags[i];
|
---|
2096 | new_tags[j + i] = -1;
|
---|
2097 | new_set[s1].tags = new_tags;
|
---|
2098 | }
|
---|
2099 | }
|
---|
2100 |
|
---|
2101 | for (s2 = 0; set2[s2].position >= 0; s2++)
|
---|
2102 | {
|
---|
2103 | new_set[s1 + s2].position = set2[s2].position;
|
---|
2104 | new_set[s1 + s2].code_min = set2[s2].code_min;
|
---|
2105 | new_set[s1 + s2].code_max = set2[s2].code_max;
|
---|
2106 | /* XXX - why not | assertions here as well? */
|
---|
2107 | new_set[s1 + s2].assertions = set2[s2].assertions;
|
---|
2108 | new_set[s1 + s2].class = set2[s2].class;
|
---|
2109 | new_set[s1 + s2].neg_classes = set2[s2].neg_classes;
|
---|
2110 | new_set[s1 + s2].backref = set2[s2].backref;
|
---|
2111 | if (set2[s2].tags == NULL)
|
---|
2112 | new_set[s1 + s2].tags = NULL;
|
---|
2113 | else
|
---|
2114 | {
|
---|
2115 | for (i = 0; set2[s2].tags[i] >= 0; i++);
|
---|
2116 | new_tags = tre_mem_alloc(mem, sizeof(*new_tags) * (i + 1));
|
---|
2117 | if (new_tags == NULL)
|
---|
2118 | return NULL;
|
---|
2119 | for (j = 0; j < i; j++)
|
---|
2120 | new_tags[j] = set2[s2].tags[j];
|
---|
2121 | new_tags[j] = -1;
|
---|
2122 | new_set[s1 + s2].tags = new_tags;
|
---|
2123 | }
|
---|
2124 | }
|
---|
2125 | new_set[s1 + s2].position = -1;
|
---|
2126 | return new_set;
|
---|
2127 | }
|
---|
2128 |
|
---|
2129 | /* Finds the empty path through `node' which is the one that should be
|
---|
2130 | taken according to POSIX.2 rules, and adds the tags on that path to
|
---|
2131 | `tags'. `tags' may be NULL. If `num_tags_seen' is not NULL, it is
|
---|
2132 | set to the number of tags seen on the path. */
|
---|
2133 | static reg_errcode_t
|
---|
2134 | tre_match_empty(tre_stack_t *stack, tre_ast_node_t *node, int *tags,
|
---|
2135 | int *assertions, int *num_tags_seen)
|
---|
2136 | {
|
---|
2137 | tre_literal_t *lit;
|
---|
2138 | tre_union_t *uni;
|
---|
2139 | tre_catenation_t *cat;
|
---|
2140 | tre_iteration_t *iter;
|
---|
2141 | int i;
|
---|
2142 | int bottom = tre_stack_num_objects(stack);
|
---|
2143 | reg_errcode_t status = REG_OK;
|
---|
2144 | if (num_tags_seen)
|
---|
2145 | *num_tags_seen = 0;
|
---|
2146 |
|
---|
2147 | status = tre_stack_push_voidptr(stack, node);
|
---|
2148 |
|
---|
2149 | /* Walk through the tree recursively. */
|
---|
2150 | while (status == REG_OK && tre_stack_num_objects(stack) > bottom)
|
---|
2151 | {
|
---|
2152 | node = tre_stack_pop_voidptr(stack);
|
---|
2153 |
|
---|
2154 | switch (node->type)
|
---|
2155 | {
|
---|
2156 | case LITERAL:
|
---|
2157 | lit = (tre_literal_t *)node->obj;
|
---|
2158 | switch (lit->code_min)
|
---|
2159 | {
|
---|
2160 | case TAG:
|
---|
2161 | if (lit->code_max >= 0)
|
---|
2162 | {
|
---|
2163 | if (tags != NULL)
|
---|
2164 | {
|
---|
2165 | /* Add the tag to `tags'. */
|
---|
2166 | for (i = 0; tags[i] >= 0; i++)
|
---|
2167 | if (tags[i] == lit->code_max)
|
---|
2168 | break;
|
---|
2169 | if (tags[i] < 0)
|
---|
2170 | {
|
---|
2171 | tags[i] = lit->code_max;
|
---|
2172 | tags[i + 1] = -1;
|
---|
2173 | }
|
---|
2174 | }
|
---|
2175 | if (num_tags_seen)
|
---|
2176 | (*num_tags_seen)++;
|
---|
2177 | }
|
---|
2178 | break;
|
---|
2179 | case ASSERTION:
|
---|
2180 | assert(lit->code_max >= 1
|
---|
2181 | || lit->code_max <= ASSERT_LAST);
|
---|
2182 | if (assertions != NULL)
|
---|
2183 | *assertions |= lit->code_max;
|
---|
2184 | break;
|
---|
2185 | case EMPTY:
|
---|
2186 | break;
|
---|
2187 | default:
|
---|
2188 | assert(0);
|
---|
2189 | break;
|
---|
2190 | }
|
---|
2191 | break;
|
---|
2192 |
|
---|
2193 | case UNION:
|
---|
2194 | /* Subexpressions starting earlier take priority over ones
|
---|
2195 | starting later, so we prefer the left subexpression over the
|
---|
2196 | right subexpression. */
|
---|
2197 | uni = (tre_union_t *)node->obj;
|
---|
2198 | if (uni->left->nullable)
|
---|
2199 | STACK_PUSHX(stack, voidptr, uni->left)
|
---|
2200 | else if (uni->right->nullable)
|
---|
2201 | STACK_PUSHX(stack, voidptr, uni->right)
|
---|
2202 | else
|
---|
2203 | assert(0);
|
---|
2204 | break;
|
---|
2205 |
|
---|
2206 | case CATENATION:
|
---|
2207 | /* The path must go through both children. */
|
---|
2208 | cat = (tre_catenation_t *)node->obj;
|
---|
2209 | assert(cat->left->nullable);
|
---|
2210 | assert(cat->right->nullable);
|
---|
2211 | STACK_PUSHX(stack, voidptr, cat->left);
|
---|
2212 | STACK_PUSHX(stack, voidptr, cat->right);
|
---|
2213 | break;
|
---|
2214 |
|
---|
2215 | case ITERATION:
|
---|
2216 | /* A match with an empty string is preferred over no match at
|
---|
2217 | all, so we go through the argument if possible. */
|
---|
2218 | iter = (tre_iteration_t *)node->obj;
|
---|
2219 | if (iter->arg->nullable)
|
---|
2220 | STACK_PUSHX(stack, voidptr, iter->arg);
|
---|
2221 | break;
|
---|
2222 |
|
---|
2223 | default:
|
---|
2224 | assert(0);
|
---|
2225 | break;
|
---|
2226 | }
|
---|
2227 | }
|
---|
2228 |
|
---|
2229 | return status;
|
---|
2230 | }
|
---|
2231 |
|
---|
2232 |
|
---|
2233 | typedef enum {
|
---|
2234 | NFL_RECURSE,
|
---|
2235 | NFL_POST_UNION,
|
---|
2236 | NFL_POST_CATENATION,
|
---|
2237 | NFL_POST_ITERATION
|
---|
2238 | } tre_nfl_stack_symbol_t;
|
---|
2239 |
|
---|
2240 |
|
---|
2241 | /* Computes and fills in the fields `nullable', `firstpos', and `lastpos' for
|
---|
2242 | the nodes of the AST `tree'. */
|
---|
2243 | static reg_errcode_t
|
---|
2244 | tre_compute_nfl(tre_mem_t mem, tre_stack_t *stack, tre_ast_node_t *tree)
|
---|
2245 | {
|
---|
2246 | int bottom = tre_stack_num_objects(stack);
|
---|
2247 |
|
---|
2248 | STACK_PUSHR(stack, voidptr, tree);
|
---|
2249 | STACK_PUSHR(stack, int, NFL_RECURSE);
|
---|
2250 |
|
---|
2251 | while (tre_stack_num_objects(stack) > bottom)
|
---|
2252 | {
|
---|
2253 | tre_nfl_stack_symbol_t symbol;
|
---|
2254 | tre_ast_node_t *node;
|
---|
2255 |
|
---|
2256 | symbol = (tre_nfl_stack_symbol_t)tre_stack_pop_int(stack);
|
---|
2257 | node = tre_stack_pop_voidptr(stack);
|
---|
2258 | switch (symbol)
|
---|
2259 | {
|
---|
2260 | case NFL_RECURSE:
|
---|
2261 | switch (node->type)
|
---|
2262 | {
|
---|
2263 | case LITERAL:
|
---|
2264 | {
|
---|
2265 | tre_literal_t *lit = (tre_literal_t *)node->obj;
|
---|
2266 | if (IS_BACKREF(lit))
|
---|
2267 | {
|
---|
2268 | /* Back references: nullable = false, firstpos = {i},
|
---|
2269 | lastpos = {i}. */
|
---|
2270 | node->nullable = 0;
|
---|
2271 | node->firstpos = tre_set_one(mem, lit->position, 0,
|
---|
2272 | TRE_CHAR_MAX, 0, NULL, -1);
|
---|
2273 | if (!node->firstpos)
|
---|
2274 | return REG_ESPACE;
|
---|
2275 | node->lastpos = tre_set_one(mem, lit->position, 0,
|
---|
2276 | TRE_CHAR_MAX, 0, NULL,
|
---|
2277 | (int)lit->code_max);
|
---|
2278 | if (!node->lastpos)
|
---|
2279 | return REG_ESPACE;
|
---|
2280 | }
|
---|
2281 | else if (lit->code_min < 0)
|
---|
2282 | {
|
---|
2283 | /* Tags, empty strings, params, and zero width assertions:
|
---|
2284 | nullable = true, firstpos = {}, and lastpos = {}. */
|
---|
2285 | node->nullable = 1;
|
---|
2286 | node->firstpos = tre_set_empty(mem);
|
---|
2287 | if (!node->firstpos)
|
---|
2288 | return REG_ESPACE;
|
---|
2289 | node->lastpos = tre_set_empty(mem);
|
---|
2290 | if (!node->lastpos)
|
---|
2291 | return REG_ESPACE;
|
---|
2292 | }
|
---|
2293 | else
|
---|
2294 | {
|
---|
2295 | /* Literal at position i: nullable = false, firstpos = {i},
|
---|
2296 | lastpos = {i}. */
|
---|
2297 | node->nullable = 0;
|
---|
2298 | node->firstpos =
|
---|
2299 | tre_set_one(mem, lit->position, (int)lit->code_min,
|
---|
2300 | (int)lit->code_max, 0, NULL, -1);
|
---|
2301 | if (!node->firstpos)
|
---|
2302 | return REG_ESPACE;
|
---|
2303 | node->lastpos = tre_set_one(mem, lit->position,
|
---|
2304 | (int)lit->code_min,
|
---|
2305 | (int)lit->code_max,
|
---|
2306 | lit->class, lit->neg_classes,
|
---|
2307 | -1);
|
---|
2308 | if (!node->lastpos)
|
---|
2309 | return REG_ESPACE;
|
---|
2310 | }
|
---|
2311 | break;
|
---|
2312 | }
|
---|
2313 |
|
---|
2314 | case UNION:
|
---|
2315 | /* Compute the attributes for the two subtrees, and after that
|
---|
2316 | for this node. */
|
---|
2317 | STACK_PUSHR(stack, voidptr, node);
|
---|
2318 | STACK_PUSHR(stack, int, NFL_POST_UNION);
|
---|
2319 | STACK_PUSHR(stack, voidptr, ((tre_union_t *)node->obj)->right);
|
---|
2320 | STACK_PUSHR(stack, int, NFL_RECURSE);
|
---|
2321 | STACK_PUSHR(stack, voidptr, ((tre_union_t *)node->obj)->left);
|
---|
2322 | STACK_PUSHR(stack, int, NFL_RECURSE);
|
---|
2323 | break;
|
---|
2324 |
|
---|
2325 | case CATENATION:
|
---|
2326 | /* Compute the attributes for the two subtrees, and after that
|
---|
2327 | for this node. */
|
---|
2328 | STACK_PUSHR(stack, voidptr, node);
|
---|
2329 | STACK_PUSHR(stack, int, NFL_POST_CATENATION);
|
---|
2330 | STACK_PUSHR(stack, voidptr, ((tre_catenation_t *)node->obj)->right);
|
---|
2331 | STACK_PUSHR(stack, int, NFL_RECURSE);
|
---|
2332 | STACK_PUSHR(stack, voidptr, ((tre_catenation_t *)node->obj)->left);
|
---|
2333 | STACK_PUSHR(stack, int, NFL_RECURSE);
|
---|
2334 | break;
|
---|
2335 |
|
---|
2336 | case ITERATION:
|
---|
2337 | /* Compute the attributes for the subtree, and after that for
|
---|
2338 | this node. */
|
---|
2339 | STACK_PUSHR(stack, voidptr, node);
|
---|
2340 | STACK_PUSHR(stack, int, NFL_POST_ITERATION);
|
---|
2341 | STACK_PUSHR(stack, voidptr, ((tre_iteration_t *)node->obj)->arg);
|
---|
2342 | STACK_PUSHR(stack, int, NFL_RECURSE);
|
---|
2343 | break;
|
---|
2344 | }
|
---|
2345 | break; /* end case: NFL_RECURSE */
|
---|
2346 |
|
---|
2347 | case NFL_POST_UNION:
|
---|
2348 | {
|
---|
2349 | tre_union_t *uni = (tre_union_t *)node->obj;
|
---|
2350 | node->nullable = uni->left->nullable || uni->right->nullable;
|
---|
2351 | node->firstpos = tre_set_union(mem, uni->left->firstpos,
|
---|
2352 | uni->right->firstpos, NULL, 0);
|
---|
2353 | if (!node->firstpos)
|
---|
2354 | return REG_ESPACE;
|
---|
2355 | node->lastpos = tre_set_union(mem, uni->left->lastpos,
|
---|
2356 | uni->right->lastpos, NULL, 0);
|
---|
2357 | if (!node->lastpos)
|
---|
2358 | return REG_ESPACE;
|
---|
2359 | break;
|
---|
2360 | }
|
---|
2361 |
|
---|
2362 | case NFL_POST_ITERATION:
|
---|
2363 | {
|
---|
2364 | tre_iteration_t *iter = (tre_iteration_t *)node->obj;
|
---|
2365 |
|
---|
2366 | if (iter->min == 0 || iter->arg->nullable)
|
---|
2367 | node->nullable = 1;
|
---|
2368 | else
|
---|
2369 | node->nullable = 0;
|
---|
2370 | node->firstpos = iter->arg->firstpos;
|
---|
2371 | node->lastpos = iter->arg->lastpos;
|
---|
2372 | break;
|
---|
2373 | }
|
---|
2374 |
|
---|
2375 | case NFL_POST_CATENATION:
|
---|
2376 | {
|
---|
2377 | int num_tags, *tags, assertions;
|
---|
2378 | reg_errcode_t status;
|
---|
2379 | tre_catenation_t *cat = node->obj;
|
---|
2380 | node->nullable = cat->left->nullable && cat->right->nullable;
|
---|
2381 |
|
---|
2382 | /* Compute firstpos. */
|
---|
2383 | if (cat->left->nullable)
|
---|
2384 | {
|
---|
2385 | /* The left side matches the empty string. Make a first pass
|
---|
2386 | with tre_match_empty() to get the number of tags and
|
---|
2387 | parameters. */
|
---|
2388 | status = tre_match_empty(stack, cat->left,
|
---|
2389 | NULL, NULL, &num_tags);
|
---|
2390 | if (status != REG_OK)
|
---|
2391 | return status;
|
---|
2392 | /* Allocate arrays for the tags and parameters. */
|
---|
2393 | tags = xmalloc(sizeof(*tags) * (num_tags + 1));
|
---|
2394 | if (!tags)
|
---|
2395 | return REG_ESPACE;
|
---|
2396 | tags[0] = -1;
|
---|
2397 | assertions = 0;
|
---|
2398 | /* Second pass with tre_mach_empty() to get the list of
|
---|
2399 | tags and parameters. */
|
---|
2400 | status = tre_match_empty(stack, cat->left, tags,
|
---|
2401 | &assertions, NULL);
|
---|
2402 | if (status != REG_OK)
|
---|
2403 | {
|
---|
2404 | xfree(tags);
|
---|
2405 | return status;
|
---|
2406 | }
|
---|
2407 | node->firstpos =
|
---|
2408 | tre_set_union(mem, cat->right->firstpos, cat->left->firstpos,
|
---|
2409 | tags, assertions);
|
---|
2410 | xfree(tags);
|
---|
2411 | if (!node->firstpos)
|
---|
2412 | return REG_ESPACE;
|
---|
2413 | }
|
---|
2414 | else
|
---|
2415 | {
|
---|
2416 | node->firstpos = cat->left->firstpos;
|
---|
2417 | }
|
---|
2418 |
|
---|
2419 | /* Compute lastpos. */
|
---|
2420 | if (cat->right->nullable)
|
---|
2421 | {
|
---|
2422 | /* The right side matches the empty string. Make a first pass
|
---|
2423 | with tre_match_empty() to get the number of tags and
|
---|
2424 | parameters. */
|
---|
2425 | status = tre_match_empty(stack, cat->right,
|
---|
2426 | NULL, NULL, &num_tags);
|
---|
2427 | if (status != REG_OK)
|
---|
2428 | return status;
|
---|
2429 | /* Allocate arrays for the tags and parameters. */
|
---|
2430 | tags = xmalloc(sizeof(int) * (num_tags + 1));
|
---|
2431 | if (!tags)
|
---|
2432 | return REG_ESPACE;
|
---|
2433 | tags[0] = -1;
|
---|
2434 | assertions = 0;
|
---|
2435 | /* Second pass with tre_mach_empty() to get the list of
|
---|
2436 | tags and parameters. */
|
---|
2437 | status = tre_match_empty(stack, cat->right, tags,
|
---|
2438 | &assertions, NULL);
|
---|
2439 | if (status != REG_OK)
|
---|
2440 | {
|
---|
2441 | xfree(tags);
|
---|
2442 | return status;
|
---|
2443 | }
|
---|
2444 | node->lastpos =
|
---|
2445 | tre_set_union(mem, cat->left->lastpos, cat->right->lastpos,
|
---|
2446 | tags, assertions);
|
---|
2447 | xfree(tags);
|
---|
2448 | if (!node->lastpos)
|
---|
2449 | return REG_ESPACE;
|
---|
2450 | }
|
---|
2451 | else
|
---|
2452 | {
|
---|
2453 | node->lastpos = cat->right->lastpos;
|
---|
2454 | }
|
---|
2455 | break;
|
---|
2456 | }
|
---|
2457 |
|
---|
2458 | default:
|
---|
2459 | assert(0);
|
---|
2460 | break;
|
---|
2461 | }
|
---|
2462 | }
|
---|
2463 |
|
---|
2464 | return REG_OK;
|
---|
2465 | }
|
---|
2466 |
|
---|
2467 |
|
---|
2468 | /* Adds a transition from each position in `p1' to each position in `p2'. */
|
---|
2469 | static reg_errcode_t
|
---|
2470 | tre_make_trans(tre_pos_and_tags_t *p1, tre_pos_and_tags_t *p2,
|
---|
2471 | tre_tnfa_transition_t *transitions,
|
---|
2472 | int *counts, int *offs)
|
---|
2473 | {
|
---|
2474 | tre_pos_and_tags_t *orig_p2 = p2;
|
---|
2475 | tre_tnfa_transition_t *trans;
|
---|
2476 | int i, j, k, l, dup, prev_p2_pos;
|
---|
2477 |
|
---|
2478 | if (transitions != NULL)
|
---|
2479 | while (p1->position >= 0)
|
---|
2480 | {
|
---|
2481 | p2 = orig_p2;
|
---|
2482 | prev_p2_pos = -1;
|
---|
2483 | while (p2->position >= 0)
|
---|
2484 | {
|
---|
2485 | /* Optimization: if this position was already handled, skip it. */
|
---|
2486 | if (p2->position == prev_p2_pos)
|
---|
2487 | {
|
---|
2488 | p2++;
|
---|
2489 | continue;
|
---|
2490 | }
|
---|
2491 | prev_p2_pos = p2->position;
|
---|
2492 | /* Set `trans' to point to the next unused transition from
|
---|
2493 | position `p1->position'. */
|
---|
2494 | trans = transitions + offs[p1->position];
|
---|
2495 | while (trans->state != NULL)
|
---|
2496 | {
|
---|
2497 | #if 0
|
---|
2498 | /* If we find a previous transition from `p1->position' to
|
---|
2499 | `p2->position', it is overwritten. This can happen only
|
---|
2500 | if there are nested loops in the regexp, like in "((a)*)*".
|
---|
2501 | In POSIX.2 repetition using the outer loop is always
|
---|
2502 | preferred over using the inner loop. Therefore the
|
---|
2503 | transition for the inner loop is useless and can be thrown
|
---|
2504 | away. */
|
---|
2505 | /* XXX - The same position is used for all nodes in a bracket
|
---|
2506 | expression, so this optimization cannot be used (it will
|
---|
2507 | break bracket expressions) unless I figure out a way to
|
---|
2508 | detect it here. */
|
---|
2509 | if (trans->state_id == p2->position)
|
---|
2510 | {
|
---|
2511 | break;
|
---|
2512 | }
|
---|
2513 | #endif
|
---|
2514 | trans++;
|
---|
2515 | }
|
---|
2516 |
|
---|
2517 | if (trans->state == NULL)
|
---|
2518 | (trans + 1)->state = NULL;
|
---|
2519 | /* Use the character ranges, assertions, etc. from `p1' for
|
---|
2520 | the transition from `p1' to `p2'. */
|
---|
2521 | trans->code_min = p1->code_min;
|
---|
2522 | trans->code_max = p1->code_max;
|
---|
2523 | trans->state = transitions + offs[p2->position];
|
---|
2524 | trans->state_id = p2->position;
|
---|
2525 | trans->assertions = p1->assertions | p2->assertions
|
---|
2526 | | (p1->class ? ASSERT_CHAR_CLASS : 0)
|
---|
2527 | | (p1->neg_classes != NULL ? ASSERT_CHAR_CLASS_NEG : 0);
|
---|
2528 | if (p1->backref >= 0)
|
---|
2529 | {
|
---|
2530 | assert((trans->assertions & ASSERT_CHAR_CLASS) == 0);
|
---|
2531 | assert(p2->backref < 0);
|
---|
2532 | trans->u.backref = p1->backref;
|
---|
2533 | trans->assertions |= ASSERT_BACKREF;
|
---|
2534 | }
|
---|
2535 | else
|
---|
2536 | trans->u.class = p1->class;
|
---|
2537 | if (p1->neg_classes != NULL)
|
---|
2538 | {
|
---|
2539 | for (i = 0; p1->neg_classes[i] != (tre_ctype_t)0; i++);
|
---|
2540 | trans->neg_classes =
|
---|
2541 | xmalloc(sizeof(*trans->neg_classes) * (i + 1));
|
---|
2542 | if (trans->neg_classes == NULL)
|
---|
2543 | return REG_ESPACE;
|
---|
2544 | for (i = 0; p1->neg_classes[i] != (tre_ctype_t)0; i++)
|
---|
2545 | trans->neg_classes[i] = p1->neg_classes[i];
|
---|
2546 | trans->neg_classes[i] = (tre_ctype_t)0;
|
---|
2547 | }
|
---|
2548 | else
|
---|
2549 | trans->neg_classes = NULL;
|
---|
2550 |
|
---|
2551 | /* Find out how many tags this transition has. */
|
---|
2552 | i = 0;
|
---|
2553 | if (p1->tags != NULL)
|
---|
2554 | while(p1->tags[i] >= 0)
|
---|
2555 | i++;
|
---|
2556 | j = 0;
|
---|
2557 | if (p2->tags != NULL)
|
---|
2558 | while(p2->tags[j] >= 0)
|
---|
2559 | j++;
|
---|
2560 |
|
---|
2561 | /* If we are overwriting a transition, free the old tag array. */
|
---|
2562 | if (trans->tags != NULL)
|
---|
2563 | xfree(trans->tags);
|
---|
2564 | trans->tags = NULL;
|
---|
2565 |
|
---|
2566 | /* If there were any tags, allocate an array and fill it. */
|
---|
2567 | if (i + j > 0)
|
---|
2568 | {
|
---|
2569 | trans->tags = xmalloc(sizeof(*trans->tags) * (i + j + 1));
|
---|
2570 | if (!trans->tags)
|
---|
2571 | return REG_ESPACE;
|
---|
2572 | i = 0;
|
---|
2573 | if (p1->tags != NULL)
|
---|
2574 | while(p1->tags[i] >= 0)
|
---|
2575 | {
|
---|
2576 | trans->tags[i] = p1->tags[i];
|
---|
2577 | i++;
|
---|
2578 | }
|
---|
2579 | l = i;
|
---|
2580 | j = 0;
|
---|
2581 | if (p2->tags != NULL)
|
---|
2582 | while (p2->tags[j] >= 0)
|
---|
2583 | {
|
---|
2584 | /* Don't add duplicates. */
|
---|
2585 | dup = 0;
|
---|
2586 | for (k = 0; k < i; k++)
|
---|
2587 | if (trans->tags[k] == p2->tags[j])
|
---|
2588 | {
|
---|
2589 | dup = 1;
|
---|
2590 | break;
|
---|
2591 | }
|
---|
2592 | if (!dup)
|
---|
2593 | trans->tags[l++] = p2->tags[j];
|
---|
2594 | j++;
|
---|
2595 | }
|
---|
2596 | trans->tags[l] = -1;
|
---|
2597 | }
|
---|
2598 |
|
---|
2599 | p2++;
|
---|
2600 | }
|
---|
2601 | p1++;
|
---|
2602 | }
|
---|
2603 | else
|
---|
2604 | /* Compute a maximum limit for the number of transitions leaving
|
---|
2605 | from each state. */
|
---|
2606 | while (p1->position >= 0)
|
---|
2607 | {
|
---|
2608 | p2 = orig_p2;
|
---|
2609 | while (p2->position >= 0)
|
---|
2610 | {
|
---|
2611 | counts[p1->position]++;
|
---|
2612 | p2++;
|
---|
2613 | }
|
---|
2614 | p1++;
|
---|
2615 | }
|
---|
2616 | return REG_OK;
|
---|
2617 | }
|
---|
2618 |
|
---|
2619 | /* Converts the syntax tree to a TNFA. All the transitions in the TNFA are
|
---|
2620 | labelled with one character range (there are no transitions on empty
|
---|
2621 | strings). The TNFA takes O(n^2) space in the worst case, `n' is size of
|
---|
2622 | the regexp. */
|
---|
2623 | static reg_errcode_t
|
---|
2624 | tre_ast_to_tnfa(tre_ast_node_t *node, tre_tnfa_transition_t *transitions,
|
---|
2625 | int *counts, int *offs)
|
---|
2626 | {
|
---|
2627 | tre_union_t *uni;
|
---|
2628 | tre_catenation_t *cat;
|
---|
2629 | tre_iteration_t *iter;
|
---|
2630 | reg_errcode_t errcode = REG_OK;
|
---|
2631 |
|
---|
2632 | /* XXX - recurse using a stack!. */
|
---|
2633 | switch (node->type)
|
---|
2634 | {
|
---|
2635 | case LITERAL:
|
---|
2636 | break;
|
---|
2637 | case UNION:
|
---|
2638 | uni = (tre_union_t *)node->obj;
|
---|
2639 | errcode = tre_ast_to_tnfa(uni->left, transitions, counts, offs);
|
---|
2640 | if (errcode != REG_OK)
|
---|
2641 | return errcode;
|
---|
2642 | errcode = tre_ast_to_tnfa(uni->right, transitions, counts, offs);
|
---|
2643 | break;
|
---|
2644 |
|
---|
2645 | case CATENATION:
|
---|
2646 | cat = (tre_catenation_t *)node->obj;
|
---|
2647 | /* Add a transition from each position in cat->left->lastpos
|
---|
2648 | to each position in cat->right->firstpos. */
|
---|
2649 | errcode = tre_make_trans(cat->left->lastpos, cat->right->firstpos,
|
---|
2650 | transitions, counts, offs);
|
---|
2651 | if (errcode != REG_OK)
|
---|
2652 | return errcode;
|
---|
2653 | errcode = tre_ast_to_tnfa(cat->left, transitions, counts, offs);
|
---|
2654 | if (errcode != REG_OK)
|
---|
2655 | return errcode;
|
---|
2656 | errcode = tre_ast_to_tnfa(cat->right, transitions, counts, offs);
|
---|
2657 | break;
|
---|
2658 |
|
---|
2659 | case ITERATION:
|
---|
2660 | iter = (tre_iteration_t *)node->obj;
|
---|
2661 | assert(iter->max == -1 || iter->max == 1);
|
---|
2662 |
|
---|
2663 | if (iter->max == -1)
|
---|
2664 | {
|
---|
2665 | assert(iter->min == 0 || iter->min == 1);
|
---|
2666 | /* Add a transition from each last position in the iterated
|
---|
2667 | expression to each first position. */
|
---|
2668 | errcode = tre_make_trans(iter->arg->lastpos, iter->arg->firstpos,
|
---|
2669 | transitions, counts, offs);
|
---|
2670 | if (errcode != REG_OK)
|
---|
2671 | return errcode;
|
---|
2672 | }
|
---|
2673 | errcode = tre_ast_to_tnfa(iter->arg, transitions, counts, offs);
|
---|
2674 | break;
|
---|
2675 | }
|
---|
2676 | return errcode;
|
---|
2677 | }
|
---|
2678 |
|
---|
2679 |
|
---|
2680 | #define ERROR_EXIT(err) \
|
---|
2681 | do \
|
---|
2682 | { \
|
---|
2683 | errcode = err; \
|
---|
2684 | if (/*CONSTCOND*/1) \
|
---|
2685 | goto error_exit; \
|
---|
2686 | } \
|
---|
2687 | while (/*CONSTCOND*/0)
|
---|
2688 |
|
---|
2689 |
|
---|
2690 | int
|
---|
2691 | regcomp(regex_t *restrict preg, const char *restrict regex, int cflags)
|
---|
2692 | {
|
---|
2693 | tre_stack_t *stack;
|
---|
2694 | tre_ast_node_t *tree, *tmp_ast_l, *tmp_ast_r;
|
---|
2695 | tre_pos_and_tags_t *p;
|
---|
2696 | int *counts = NULL, *offs = NULL;
|
---|
2697 | int i, add = 0;
|
---|
2698 | tre_tnfa_transition_t *transitions, *initial;
|
---|
2699 | tre_tnfa_t *tnfa = NULL;
|
---|
2700 | tre_submatch_data_t *submatch_data;
|
---|
2701 | tre_tag_direction_t *tag_directions = NULL;
|
---|
2702 | reg_errcode_t errcode;
|
---|
2703 | tre_mem_t mem;
|
---|
2704 |
|
---|
2705 | /* Parse context. */
|
---|
2706 | tre_parse_ctx_t parse_ctx;
|
---|
2707 |
|
---|
2708 | /* Allocate a stack used throughout the compilation process for various
|
---|
2709 | purposes. */
|
---|
2710 | stack = tre_stack_new(512, 1024000, 128);
|
---|
2711 | if (!stack)
|
---|
2712 | return REG_ESPACE;
|
---|
2713 | /* Allocate a fast memory allocator. */
|
---|
2714 | mem = tre_mem_new();
|
---|
2715 | if (!mem)
|
---|
2716 | {
|
---|
2717 | tre_stack_destroy(stack);
|
---|
2718 | return REG_ESPACE;
|
---|
2719 | }
|
---|
2720 |
|
---|
2721 | /* Parse the regexp. */
|
---|
2722 | memset(&parse_ctx, 0, sizeof(parse_ctx));
|
---|
2723 | parse_ctx.mem = mem;
|
---|
2724 | parse_ctx.stack = stack;
|
---|
2725 | parse_ctx.start = regex;
|
---|
2726 | parse_ctx.cflags = cflags;
|
---|
2727 | parse_ctx.max_backref = -1;
|
---|
2728 | errcode = tre_parse(&parse_ctx);
|
---|
2729 | if (errcode != REG_OK)
|
---|
2730 | ERROR_EXIT(errcode);
|
---|
2731 | preg->re_nsub = parse_ctx.submatch_id - 1;
|
---|
2732 | tree = parse_ctx.n;
|
---|
2733 |
|
---|
2734 | #ifdef TRE_DEBUG
|
---|
2735 | tre_ast_print(tree);
|
---|
2736 | #endif /* TRE_DEBUG */
|
---|
2737 |
|
---|
2738 | /* Referring to nonexistent subexpressions is illegal. */
|
---|
2739 | if (parse_ctx.max_backref > (int)preg->re_nsub)
|
---|
2740 | ERROR_EXIT(REG_ESUBREG);
|
---|
2741 |
|
---|
2742 | /* Allocate the TNFA struct. */
|
---|
2743 | tnfa = xcalloc(1, sizeof(tre_tnfa_t));
|
---|
2744 | if (tnfa == NULL)
|
---|
2745 | ERROR_EXIT(REG_ESPACE);
|
---|
2746 | tnfa->have_backrefs = parse_ctx.max_backref >= 0;
|
---|
2747 | tnfa->have_approx = 0;
|
---|
2748 | tnfa->num_submatches = parse_ctx.submatch_id;
|
---|
2749 |
|
---|
2750 | /* Set up tags for submatch addressing. If REG_NOSUB is set and the
|
---|
2751 | regexp does not have back references, this can be skipped. */
|
---|
2752 | if (tnfa->have_backrefs || !(cflags & REG_NOSUB))
|
---|
2753 | {
|
---|
2754 |
|
---|
2755 | /* Figure out how many tags we will need. */
|
---|
2756 | errcode = tre_add_tags(NULL, stack, tree, tnfa);
|
---|
2757 | if (errcode != REG_OK)
|
---|
2758 | ERROR_EXIT(errcode);
|
---|
2759 |
|
---|
2760 | if (tnfa->num_tags > 0)
|
---|
2761 | {
|
---|
2762 | tag_directions = xmalloc(sizeof(*tag_directions)
|
---|
2763 | * (tnfa->num_tags + 1));
|
---|
2764 | if (tag_directions == NULL)
|
---|
2765 | ERROR_EXIT(REG_ESPACE);
|
---|
2766 | tnfa->tag_directions = tag_directions;
|
---|
2767 | memset(tag_directions, -1,
|
---|
2768 | sizeof(*tag_directions) * (tnfa->num_tags + 1));
|
---|
2769 | }
|
---|
2770 | tnfa->minimal_tags = xcalloc((unsigned)tnfa->num_tags * 2 + 1,
|
---|
2771 | sizeof(*tnfa->minimal_tags));
|
---|
2772 | if (tnfa->minimal_tags == NULL)
|
---|
2773 | ERROR_EXIT(REG_ESPACE);
|
---|
2774 |
|
---|
2775 | submatch_data = xcalloc((unsigned)parse_ctx.submatch_id,
|
---|
2776 | sizeof(*submatch_data));
|
---|
2777 | if (submatch_data == NULL)
|
---|
2778 | ERROR_EXIT(REG_ESPACE);
|
---|
2779 | tnfa->submatch_data = submatch_data;
|
---|
2780 |
|
---|
2781 | errcode = tre_add_tags(mem, stack, tree, tnfa);
|
---|
2782 | if (errcode != REG_OK)
|
---|
2783 | ERROR_EXIT(errcode);
|
---|
2784 |
|
---|
2785 | }
|
---|
2786 |
|
---|
2787 | /* Expand iteration nodes. */
|
---|
2788 | errcode = tre_expand_ast(mem, stack, tree, &parse_ctx.position,
|
---|
2789 | tag_directions);
|
---|
2790 | if (errcode != REG_OK)
|
---|
2791 | ERROR_EXIT(errcode);
|
---|
2792 |
|
---|
2793 | /* Add a dummy node for the final state.
|
---|
2794 | XXX - For certain patterns this dummy node can be optimized away,
|
---|
2795 | for example "a*" or "ab*". Figure out a simple way to detect
|
---|
2796 | this possibility. */
|
---|
2797 | tmp_ast_l = tree;
|
---|
2798 | tmp_ast_r = tre_ast_new_literal(mem, 0, 0, parse_ctx.position++);
|
---|
2799 | if (tmp_ast_r == NULL)
|
---|
2800 | ERROR_EXIT(REG_ESPACE);
|
---|
2801 |
|
---|
2802 | tree = tre_ast_new_catenation(mem, tmp_ast_l, tmp_ast_r);
|
---|
2803 | if (tree == NULL)
|
---|
2804 | ERROR_EXIT(REG_ESPACE);
|
---|
2805 |
|
---|
2806 | errcode = tre_compute_nfl(mem, stack, tree);
|
---|
2807 | if (errcode != REG_OK)
|
---|
2808 | ERROR_EXIT(errcode);
|
---|
2809 |
|
---|
2810 | counts = xmalloc(sizeof(int) * parse_ctx.position);
|
---|
2811 | if (counts == NULL)
|
---|
2812 | ERROR_EXIT(REG_ESPACE);
|
---|
2813 |
|
---|
2814 | offs = xmalloc(sizeof(int) * parse_ctx.position);
|
---|
2815 | if (offs == NULL)
|
---|
2816 | ERROR_EXIT(REG_ESPACE);
|
---|
2817 |
|
---|
2818 | for (i = 0; i < parse_ctx.position; i++)
|
---|
2819 | counts[i] = 0;
|
---|
2820 | tre_ast_to_tnfa(tree, NULL, counts, NULL);
|
---|
2821 |
|
---|
2822 | add = 0;
|
---|
2823 | for (i = 0; i < parse_ctx.position; i++)
|
---|
2824 | {
|
---|
2825 | offs[i] = add;
|
---|
2826 | add += counts[i] + 1;
|
---|
2827 | counts[i] = 0;
|
---|
2828 | }
|
---|
2829 | transitions = xcalloc((unsigned)add + 1, sizeof(*transitions));
|
---|
2830 | if (transitions == NULL)
|
---|
2831 | ERROR_EXIT(REG_ESPACE);
|
---|
2832 | tnfa->transitions = transitions;
|
---|
2833 | tnfa->num_transitions = add;
|
---|
2834 |
|
---|
2835 | errcode = tre_ast_to_tnfa(tree, transitions, counts, offs);
|
---|
2836 | if (errcode != REG_OK)
|
---|
2837 | ERROR_EXIT(errcode);
|
---|
2838 |
|
---|
2839 | tnfa->firstpos_chars = NULL;
|
---|
2840 |
|
---|
2841 | p = tree->firstpos;
|
---|
2842 | i = 0;
|
---|
2843 | while (p->position >= 0)
|
---|
2844 | {
|
---|
2845 | i++;
|
---|
2846 | p++;
|
---|
2847 | }
|
---|
2848 |
|
---|
2849 | initial = xcalloc((unsigned)i + 1, sizeof(tre_tnfa_transition_t));
|
---|
2850 | if (initial == NULL)
|
---|
2851 | ERROR_EXIT(REG_ESPACE);
|
---|
2852 | tnfa->initial = initial;
|
---|
2853 |
|
---|
2854 | i = 0;
|
---|
2855 | for (p = tree->firstpos; p->position >= 0; p++)
|
---|
2856 | {
|
---|
2857 | initial[i].state = transitions + offs[p->position];
|
---|
2858 | initial[i].state_id = p->position;
|
---|
2859 | initial[i].tags = NULL;
|
---|
2860 | /* Copy the arrays p->tags, and p->params, they are allocated
|
---|
2861 | from a tre_mem object. */
|
---|
2862 | if (p->tags)
|
---|
2863 | {
|
---|
2864 | int j;
|
---|
2865 | for (j = 0; p->tags[j] >= 0; j++);
|
---|
2866 | initial[i].tags = xmalloc(sizeof(*p->tags) * (j + 1));
|
---|
2867 | if (!initial[i].tags)
|
---|
2868 | ERROR_EXIT(REG_ESPACE);
|
---|
2869 | memcpy(initial[i].tags, p->tags, sizeof(*p->tags) * (j + 1));
|
---|
2870 | }
|
---|
2871 | initial[i].assertions = p->assertions;
|
---|
2872 | i++;
|
---|
2873 | }
|
---|
2874 | initial[i].state = NULL;
|
---|
2875 |
|
---|
2876 | tnfa->num_transitions = add;
|
---|
2877 | tnfa->final = transitions + offs[tree->lastpos[0].position];
|
---|
2878 | tnfa->num_states = parse_ctx.position;
|
---|
2879 | tnfa->cflags = cflags;
|
---|
2880 |
|
---|
2881 | tre_mem_destroy(mem);
|
---|
2882 | tre_stack_destroy(stack);
|
---|
2883 | xfree(counts);
|
---|
2884 | xfree(offs);
|
---|
2885 |
|
---|
2886 | preg->TRE_REGEX_T_FIELD = (void *)tnfa;
|
---|
2887 | return REG_OK;
|
---|
2888 |
|
---|
2889 | error_exit:
|
---|
2890 | /* Free everything that was allocated and return the error code. */
|
---|
2891 | tre_mem_destroy(mem);
|
---|
2892 | if (stack != NULL)
|
---|
2893 | tre_stack_destroy(stack);
|
---|
2894 | if (counts != NULL)
|
---|
2895 | xfree(counts);
|
---|
2896 | if (offs != NULL)
|
---|
2897 | xfree(offs);
|
---|
2898 | preg->TRE_REGEX_T_FIELD = (void *)tnfa;
|
---|
2899 | regfree(preg);
|
---|
2900 | return errcode;
|
---|
2901 | }
|
---|
2902 |
|
---|
2903 |
|
---|
2904 |
|
---|
2905 |
|
---|
2906 | void
|
---|
2907 | regfree(regex_t *preg)
|
---|
2908 | {
|
---|
2909 | tre_tnfa_t *tnfa;
|
---|
2910 | unsigned int i;
|
---|
2911 | tre_tnfa_transition_t *trans;
|
---|
2912 |
|
---|
2913 | tnfa = (void *)preg->TRE_REGEX_T_FIELD;
|
---|
2914 | if (!tnfa)
|
---|
2915 | return;
|
---|
2916 |
|
---|
2917 | for (i = 0; i < tnfa->num_transitions; i++)
|
---|
2918 | if (tnfa->transitions[i].state)
|
---|
2919 | {
|
---|
2920 | if (tnfa->transitions[i].tags)
|
---|
2921 | xfree(tnfa->transitions[i].tags);
|
---|
2922 | if (tnfa->transitions[i].neg_classes)
|
---|
2923 | xfree(tnfa->transitions[i].neg_classes);
|
---|
2924 | }
|
---|
2925 | if (tnfa->transitions)
|
---|
2926 | xfree(tnfa->transitions);
|
---|
2927 |
|
---|
2928 | if (tnfa->initial)
|
---|
2929 | {
|
---|
2930 | for (trans = tnfa->initial; trans->state; trans++)
|
---|
2931 | {
|
---|
2932 | if (trans->tags)
|
---|
2933 | xfree(trans->tags);
|
---|
2934 | }
|
---|
2935 | xfree(tnfa->initial);
|
---|
2936 | }
|
---|
2937 |
|
---|
2938 | if (tnfa->submatch_data)
|
---|
2939 | {
|
---|
2940 | for (i = 0; i < tnfa->num_submatches; i++)
|
---|
2941 | if (tnfa->submatch_data[i].parents)
|
---|
2942 | xfree(tnfa->submatch_data[i].parents);
|
---|
2943 | xfree(tnfa->submatch_data);
|
---|
2944 | }
|
---|
2945 |
|
---|
2946 | if (tnfa->tag_directions)
|
---|
2947 | xfree(tnfa->tag_directions);
|
---|
2948 | if (tnfa->firstpos_chars)
|
---|
2949 | xfree(tnfa->firstpos_chars);
|
---|
2950 | if (tnfa->minimal_tags)
|
---|
2951 | xfree(tnfa->minimal_tags);
|
---|
2952 | xfree(tnfa);
|
---|
2953 | }
|
---|