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| 1 | +<?php |
| 2 | + |
| 3 | +/** |
| 4 | + * Parses an Index hint. |
| 5 | + */ |
| 6 | + |
| 7 | +namespace PhpMyAdmin\SqlParser\Components; |
| 8 | + |
| 9 | +use PhpMyAdmin\SqlParser\Component; |
| 10 | +use PhpMyAdmin\SqlParser\Parser; |
| 11 | +use PhpMyAdmin\SqlParser\Token; |
| 12 | +use PhpMyAdmin\SqlParser\TokensList; |
| 13 | + |
| 14 | +/** |
| 15 | + * Parses an Index hint. |
| 16 | + * |
| 17 | + * @category Components |
| 18 | + * |
| 19 | + * @license https://www.gnu.org/licenses/gpl-2.0.txt GPL-2.0+ |
| 20 | + */ |
| 21 | +class IndexHint extends Component |
| 22 | +{ |
| 23 | + /** |
| 24 | + * The type of hint (USE/FORCE/IGNORE) |
| 25 | + * |
| 26 | + * @var string |
| 27 | + */ |
| 28 | + public $type; |
| 29 | + |
| 30 | + /** |
| 31 | + * What the hint is for (INDEX/KEY) |
| 32 | + * |
| 33 | + * @var string |
| 34 | + */ |
| 35 | + public $indexOrKey; |
| 36 | + |
| 37 | + /** |
| 38 | + * The clause for which this hint is (JOIN/ORDER BY/GROUP BY) |
| 39 | + * |
| 40 | + * @var string |
| 41 | + */ |
| 42 | + public $for; |
| 43 | + |
| 44 | + /** |
| 45 | + * List of indexes in this hint |
| 46 | + * |
| 47 | + * @var array |
| 48 | + */ |
| 49 | + public $indexes = array(); |
| 50 | + |
| 51 | + /** |
| 52 | + * Constructor. |
| 53 | + * |
| 54 | + * @param string $type the type of hint (USE/FORCE/IGNORE) |
| 55 | + * @param string $indexOrKey What the hint is for (INDEX/KEY) |
| 56 | + * @param string $for the clause for which this hint is (JOIN/ORDER BY/GROUP BY) |
| 57 | + * @param string $indexes List of indexes in this hint |
| 58 | + */ |
| 59 | + public function __construct(string $type = null, string $indexOrKey = null, string $for = null, array $indexes = array()) |
| 60 | + { |
| 61 | + $this->type = $type; |
| 62 | + $this->indexOrKey = $indexOrKey; |
| 63 | + $this->for = $for; |
| 64 | + $this->indexes = $indexes; |
| 65 | + } |
| 66 | + |
| 67 | + /** |
| 68 | + * @param Parser $parser the parser that serves as context |
| 69 | + * @param TokensList $list the list of tokens that are being parsed |
| 70 | + * @param array $options parameters for parsing |
| 71 | + * |
| 72 | + * @return IndexHint|Component[] |
| 73 | + */ |
| 74 | + public static function parse(Parser $parser, TokensList $list, array $options = array()) |
| 75 | + { |
| 76 | + $ret = array(); |
| 77 | + $expr = new self(); |
| 78 | + $expr->type = isset($options['type']) ? $options['type'] : null; |
| 79 | + /** |
| 80 | + * The state of the parser. |
| 81 | + * |
| 82 | + * Below are the states of the parser. |
| 83 | + * 0 ----------------- [ USE/IGNORE/FORCE ]-----------------> 1 |
| 84 | + * 1 -------------------- [ INDEX/KEY ] --------------------> 2 |
| 85 | + * 2 ----------------------- [ FOR ] -----------------------> 3 |
| 86 | + * 2 -------------------- [ expr_list ] --------------------> 0 |
| 87 | + * 3 -------------- [ JOIN/GROUP BY/ORDER BY ] -------------> 4 |
| 88 | + * 4 -------------------- [ expr_list ] --------------------> 0 |
| 89 | + * @var int |
| 90 | + */ |
| 91 | + $state = 0; |
| 92 | + |
| 93 | + // By design, the parser will parse first token after the keyword. So, the keyword |
| 94 | + // must be analyzed too, in order to determine the type of this index hint. |
| 95 | + if ($list->idx > 0) { |
| 96 | + --$list->idx; |
| 97 | + } |
| 98 | + for (; $list->idx < $list->count; ++$list->idx) { |
| 99 | + /** |
| 100 | + * Token parsed at this moment. |
| 101 | + * |
| 102 | + * @var Token |
| 103 | + */ |
| 104 | + $token = $list->tokens[$list->idx]; |
| 105 | + |
| 106 | + // End of statement. |
| 107 | + if ($token->type === Token::TYPE_DELIMITER) { |
| 108 | + break; |
| 109 | + } |
| 110 | + // Skipping whitespaces and comments. |
| 111 | + if (($token->type === Token::TYPE_WHITESPACE) || ($token->type === Token::TYPE_COMMENT)) { |
| 112 | + continue; |
| 113 | + } |
| 114 | + |
| 115 | + switch ($state) { |
| 116 | + case 0: |
| 117 | + if ($token->type === Token::TYPE_KEYWORD) { |
| 118 | + if ($token->keyword === 'USE' || $token->keyword === 'IGNORE' || $token->keyword === 'FORCE') { |
| 119 | + $expr->type = $token->keyword; |
| 120 | + $state = 1; |
| 121 | + } else { |
| 122 | + break 2; |
| 123 | + } |
| 124 | + } |
| 125 | + break; |
| 126 | + case 1: |
| 127 | + if ($token->type === Token::TYPE_KEYWORD) { |
| 128 | + if ($token->keyword === 'INDEX' || $token->keyword === 'KEY') { |
| 129 | + $expr->indexOrKey = $token->keyword; |
| 130 | + } else { |
| 131 | + $parser->error('Unexpected keyword.', $token); |
| 132 | + } |
| 133 | + $state = 2; |
| 134 | + } else { |
| 135 | + // we expect the token to be a keyword |
| 136 | + $parser->error('Unexpected token.', $token); |
| 137 | + } |
| 138 | + break; |
| 139 | + case 2: |
| 140 | + if ($token->type === Token::TYPE_KEYWORD && $token->keyword === 'FOR') { |
| 141 | + $state = 3; |
| 142 | + } else { |
| 143 | + $expr->indexes = ExpressionArray::parse($parser, $list); |
| 144 | + $state = 0; |
| 145 | + $ret[] = $expr; |
| 146 | + $expr = new self(); |
| 147 | + } |
| 148 | + break; |
| 149 | + case 3: |
| 150 | + if ($token->type === Token::TYPE_KEYWORD) { |
| 151 | + if ($token->keyword === 'JOIN' || $token->keyword === 'GROUP BY' || $token->keyword === 'ORDER BY') { |
| 152 | + $expr->for = $token->keyword; |
| 153 | + } else { |
| 154 | + $parser->error('Unexpected keyword.', $token); |
| 155 | + } |
| 156 | + $state = 4; |
| 157 | + } else { |
| 158 | + // we expect the token to be a keyword |
| 159 | + $parser->error('Unexpected token.', $token); |
| 160 | + } |
| 161 | + break; |
| 162 | + case 4: |
| 163 | + $expr->indexes = ExpressionArray::parse($parser, $list); |
| 164 | + $state = 0; |
| 165 | + $ret[] = $expr; |
| 166 | + $expr = new self(); |
| 167 | + break; |
| 168 | + } |
| 169 | + } |
| 170 | + --$list->idx; |
| 171 | + |
| 172 | + return $ret; |
| 173 | + } |
| 174 | + |
| 175 | + /** |
| 176 | + * @param ArrayObj|ArrayObj[] $component the component to be built |
| 177 | + * @param array $options parameters for building |
| 178 | + * |
| 179 | + * @return string |
| 180 | + */ |
| 181 | + public static function build($component, array $options = array()) |
| 182 | + { |
| 183 | + if (is_array($component)) { |
| 184 | + return implode(' ', $component); |
| 185 | + } |
| 186 | + |
| 187 | + $ret = $component->type . ' ' . $component->indexOrKey . ' '; |
| 188 | + if ($component->for !== null) { |
| 189 | + $ret .= 'FOR ' . $component->for . ' '; |
| 190 | + } |
| 191 | + return $ret . ExpressionArray::build($component->indexes); |
| 192 | + } |
| 193 | +} |
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