1<?php 2 3/* 4 * This file is part of the Symfony package. 5 * 6 * (c) Fabien Potencier <fabien@symfony.com> 7 * 8 * For the full copyright and license information, please view the LICENSE 9 * file that was distributed with this source code. 10 */ 11 12namespace Symfony\Component\Mime; 13 14/** 15 * @author Fabien Potencier <fabien@symfony.com> 16 * @author Xavier De Cock <xdecock@gmail.com> 17 * 18 * @internal 19 */ 20final class CharacterStream 21{ 22 /** Pre-computed for optimization */ 23 private const UTF8_LENGTH_MAP = [ 24 "\x00" => 1, "\x01" => 1, "\x02" => 1, "\x03" => 1, "\x04" => 1, "\x05" => 1, "\x06" => 1, "\x07" => 1, 25 "\x08" => 1, "\x09" => 1, "\x0a" => 1, "\x0b" => 1, "\x0c" => 1, "\x0d" => 1, "\x0e" => 1, "\x0f" => 1, 26 "\x10" => 1, "\x11" => 1, "\x12" => 1, "\x13" => 1, "\x14" => 1, "\x15" => 1, "\x16" => 1, "\x17" => 1, 27 "\x18" => 1, "\x19" => 1, "\x1a" => 1, "\x1b" => 1, "\x1c" => 1, "\x1d" => 1, "\x1e" => 1, "\x1f" => 1, 28 "\x20" => 1, "\x21" => 1, "\x22" => 1, "\x23" => 1, "\x24" => 1, "\x25" => 1, "\x26" => 1, "\x27" => 1, 29 "\x28" => 1, "\x29" => 1, "\x2a" => 1, "\x2b" => 1, "\x2c" => 1, "\x2d" => 1, "\x2e" => 1, "\x2f" => 1, 30 "\x30" => 1, "\x31" => 1, "\x32" => 1, "\x33" => 1, "\x34" => 1, "\x35" => 1, "\x36" => 1, "\x37" => 1, 31 "\x38" => 1, "\x39" => 1, "\x3a" => 1, "\x3b" => 1, "\x3c" => 1, "\x3d" => 1, "\x3e" => 1, "\x3f" => 1, 32 "\x40" => 1, "\x41" => 1, "\x42" => 1, "\x43" => 1, "\x44" => 1, "\x45" => 1, "\x46" => 1, "\x47" => 1, 33 "\x48" => 1, "\x49" => 1, "\x4a" => 1, "\x4b" => 1, "\x4c" => 1, "\x4d" => 1, "\x4e" => 1, "\x4f" => 1, 34 "\x50" => 1, "\x51" => 1, "\x52" => 1, "\x53" => 1, "\x54" => 1, "\x55" => 1, "\x56" => 1, "\x57" => 1, 35 "\x58" => 1, "\x59" => 1, "\x5a" => 1, "\x5b" => 1, "\x5c" => 1, "\x5d" => 1, "\x5e" => 1, "\x5f" => 1, 36 "\x60" => 1, "\x61" => 1, "\x62" => 1, "\x63" => 1, "\x64" => 1, "\x65" => 1, "\x66" => 1, "\x67" => 1, 37 "\x68" => 1, "\x69" => 1, "\x6a" => 1, "\x6b" => 1, "\x6c" => 1, "\x6d" => 1, "\x6e" => 1, "\x6f" => 1, 38 "\x70" => 1, "\x71" => 1, "\x72" => 1, "\x73" => 1, "\x74" => 1, "\x75" => 1, "\x76" => 1, "\x77" => 1, 39 "\x78" => 1, "\x79" => 1, "\x7a" => 1, "\x7b" => 1, "\x7c" => 1, "\x7d" => 1, "\x7e" => 1, "\x7f" => 1, 40 "\x80" => 0, "\x81" => 0, "\x82" => 0, "\x83" => 0, "\x84" => 0, "\x85" => 0, "\x86" => 0, "\x87" => 0, 41 "\x88" => 0, "\x89" => 0, "\x8a" => 0, "\x8b" => 0, "\x8c" => 0, "\x8d" => 0, "\x8e" => 0, "\x8f" => 0, 42 "\x90" => 0, "\x91" => 0, "\x92" => 0, "\x93" => 0, "\x94" => 0, "\x95" => 0, "\x96" => 0, "\x97" => 0, 43 "\x98" => 0, "\x99" => 0, "\x9a" => 0, "\x9b" => 0, "\x9c" => 0, "\x9d" => 0, "\x9e" => 0, "\x9f" => 0, 44 "\xa0" => 0, "\xa1" => 0, "\xa2" => 0, "\xa3" => 0, "\xa4" => 0, "\xa5" => 0, "\xa6" => 0, "\xa7" => 0, 45 "\xa8" => 0, "\xa9" => 0, "\xaa" => 0, "\xab" => 0, "\xac" => 0, "\xad" => 0, "\xae" => 0, "\xaf" => 0, 46 "\xb0" => 0, "\xb1" => 0, "\xb2" => 0, "\xb3" => 0, "\xb4" => 0, "\xb5" => 0, "\xb6" => 0, "\xb7" => 0, 47 "\xb8" => 0, "\xb9" => 0, "\xba" => 0, "\xbb" => 0, "\xbc" => 0, "\xbd" => 0, "\xbe" => 0, "\xbf" => 0, 48 "\xc0" => 2, "\xc1" => 2, "\xc2" => 2, "\xc3" => 2, "\xc4" => 2, "\xc5" => 2, "\xc6" => 2, "\xc7" => 2, 49 "\xc8" => 2, "\xc9" => 2, "\xca" => 2, "\xcb" => 2, "\xcc" => 2, "\xcd" => 2, "\xce" => 2, "\xcf" => 2, 50 "\xd0" => 2, "\xd1" => 2, "\xd2" => 2, "\xd3" => 2, "\xd4" => 2, "\xd5" => 2, "\xd6" => 2, "\xd7" => 2, 51 "\xd8" => 2, "\xd9" => 2, "\xda" => 2, "\xdb" => 2, "\xdc" => 2, "\xdd" => 2, "\xde" => 2, "\xdf" => 2, 52 "\xe0" => 3, "\xe1" => 3, "\xe2" => 3, "\xe3" => 3, "\xe4" => 3, "\xe5" => 3, "\xe6" => 3, "\xe7" => 3, 53 "\xe8" => 3, "\xe9" => 3, "\xea" => 3, "\xeb" => 3, "\xec" => 3, "\xed" => 3, "\xee" => 3, "\xef" => 3, 54 "\xf0" => 4, "\xf1" => 4, "\xf2" => 4, "\xf3" => 4, "\xf4" => 4, "\xf5" => 4, "\xf6" => 4, "\xf7" => 4, 55 "\xf8" => 5, "\xf9" => 5, "\xfa" => 5, "\xfb" => 5, "\xfc" => 6, "\xfd" => 6, "\xfe" => 0, "\xff" => 0, 56 ]; 57 58 private $data = ''; 59 private $dataSize = 0; 60 private $map = []; 61 private $charCount = 0; 62 private $currentPos = 0; 63 private $fixedWidth = 0; 64 65 /** 66 * @param resource|string $input 67 */ 68 public function __construct($input, ?string $charset = 'utf-8') 69 { 70 $charset = strtolower(trim($charset)) ?: 'utf-8'; 71 if ('utf-8' === $charset || 'utf8' === $charset) { 72 $this->fixedWidth = 0; 73 $this->map = ['p' => [], 'i' => []]; 74 } else { 75 switch ($charset) { 76 // 16 bits 77 case 'ucs2': 78 case 'ucs-2': 79 case 'utf16': 80 case 'utf-16': 81 $this->fixedWidth = 2; 82 break; 83 84 // 32 bits 85 case 'ucs4': 86 case 'ucs-4': 87 case 'utf32': 88 case 'utf-32': 89 $this->fixedWidth = 4; 90 break; 91 92 // 7-8 bit charsets: (us-)?ascii, (iso|iec)-?8859-?[0-9]+, windows-?125[0-9], cp-?[0-9]+, ansi, macintosh, 93 // koi-?7, koi-?8-?.+, mik, (cork|t1), v?iscii 94 // and fallback 95 default: 96 $this->fixedWidth = 1; 97 } 98 } 99 if (\is_resource($input)) { 100 $blocks = 512; 101 if (stream_get_meta_data($input)['seekable'] ?? false) { 102 rewind($input); 103 } 104 while (false !== $read = fread($input, $blocks)) { 105 $this->write($read); 106 } 107 } else { 108 $this->write($input); 109 } 110 } 111 112 public function read(int $length): ?string 113 { 114 if ($this->currentPos >= $this->charCount) { 115 return null; 116 } 117 $length = ($this->currentPos + $length > $this->charCount) ? $this->charCount - $this->currentPos : $length; 118 if ($this->fixedWidth > 0) { 119 $len = $length * $this->fixedWidth; 120 $ret = substr($this->data, $this->currentPos * $this->fixedWidth, $len); 121 $this->currentPos += $length; 122 } else { 123 $end = $this->currentPos + $length; 124 $end = $end > $this->charCount ? $this->charCount : $end; 125 $ret = ''; 126 $start = 0; 127 if ($this->currentPos > 0) { 128 $start = $this->map['p'][$this->currentPos - 1]; 129 } 130 $to = $start; 131 for (; $this->currentPos < $end; ++$this->currentPos) { 132 if (isset($this->map['i'][$this->currentPos])) { 133 $ret .= substr($this->data, $start, $to - $start).'?'; 134 $start = $this->map['p'][$this->currentPos]; 135 } else { 136 $to = $this->map['p'][$this->currentPos]; 137 } 138 } 139 $ret .= substr($this->data, $start, $to - $start); 140 } 141 142 return $ret; 143 } 144 145 public function readBytes(int $length): ?array 146 { 147 if (null !== $read = $this->read($length)) { 148 return array_map('ord', str_split($read, 1)); 149 } 150 151 return null; 152 } 153 154 public function setPointer(int $charOffset): void 155 { 156 if ($this->charCount < $charOffset) { 157 $charOffset = $this->charCount; 158 } 159 $this->currentPos = $charOffset; 160 } 161 162 public function write(string $chars): void 163 { 164 $ignored = ''; 165 $this->data .= $chars; 166 if ($this->fixedWidth > 0) { 167 $strlen = \strlen($chars); 168 $ignoredL = $strlen % $this->fixedWidth; 169 $ignored = $ignoredL ? substr($chars, -$ignoredL) : ''; 170 $this->charCount += ($strlen - $ignoredL) / $this->fixedWidth; 171 } else { 172 $this->charCount += $this->getUtf8CharPositions($chars, $this->dataSize, $ignored); 173 } 174 $this->dataSize = \strlen($this->data) - \strlen($ignored); 175 } 176 177 private function getUtf8CharPositions(string $string, int $startOffset, string &$ignoredChars): int 178 { 179 $strlen = \strlen($string); 180 $charPos = \count($this->map['p']); 181 $foundChars = 0; 182 $invalid = false; 183 for ($i = 0; $i < $strlen; ++$i) { 184 $char = $string[$i]; 185 $size = self::UTF8_LENGTH_MAP[$char]; 186 if (0 == $size) { 187 /* char is invalid, we must wait for a resync */ 188 $invalid = true; 189 continue; 190 } 191 192 if ($invalid) { 193 /* We mark the chars as invalid and start a new char */ 194 $this->map['p'][$charPos + $foundChars] = $startOffset + $i; 195 $this->map['i'][$charPos + $foundChars] = true; 196 ++$foundChars; 197 $invalid = false; 198 } 199 if (($i + $size) > $strlen) { 200 $ignoredChars = substr($string, $i); 201 break; 202 } 203 for ($j = 1; $j < $size; ++$j) { 204 $char = $string[$i + $j]; 205 if ($char > "\x7F" && $char < "\xC0") { 206 // Valid - continue parsing 207 } else { 208 /* char is invalid, we must wait for a resync */ 209 $invalid = true; 210 continue 2; 211 } 212 } 213 /* Ok we got a complete char here */ 214 $this->map['p'][$charPos + $foundChars] = $startOffset + $i + $size; 215 $i += $j - 1; 216 ++$foundChars; 217 } 218 219 return $foundChars; 220 } 221} 222