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<?php
/**
* BaconQrCode
*
* @link http://github.com/Bacon/BaconQrCode For the canonical source repository
* @copyright 2013 Ben 'DASPRiD' Scholzen
* @license http://opensource.org/licenses/BSD-2-Clause Simplified BSD License
*/
namespace BaconQrCode\Common;
use PHPUnit_Framework_TestCase as TestCase;
use SplFixedArray;
class ReedSolomonTest extends TestCase
{
public static function tabProvider()
{
return array(
array(2, 0x7, 1, 1, 1),
array(3, 0xb, 1, 1, 2),
array(4, 0x13, 1, 1, 4),
array(5, 0x25, 1, 1, 6),
array(6, 0x43, 1, 1, 8),
array(7, 0x89, 1, 1, 10),
array(8, 0x11d, 1, 1, 32),
);
}
/**
* @dataProvider tabProvider
* @param integer $symbolSize
* @param integer $generatorPoly
* @param integer $firstRoot
* @param integer $primitive
* @param integer $numRoots
* @return void
*/
public function testCodec($symbolSize, $generatorPoly, $firstRoot, $primitive, $numRoots)
{
if (defined('MT_RAND_PHP')) {
mt_srand(0xdeadbeef, MT_RAND_PHP);
} else {
mt_srand(0xdeadbeef);
}
$blockSize = (1 << $symbolSize) - 1;
$dataSize = $blockSize - $numRoots;
$codec = new ReedSolomonCodec($symbolSize, $generatorPoly, $firstRoot, $primitive, $numRoots, 0);
for ($errors = 0; $errors <= $numRoots / 2; $errors++) {
// Load block with random data and encode
$block = SplFixedArray::fromArray(array_fill(0, $blockSize, 0), false);
for ($i = 0; $i < $dataSize; $i++) {
$block[$i] = mt_rand(0, $blockSize);
}
// Make temporary copy
$tBlock = clone $block;
$parity = SplFixedArray::fromArray(array_fill(0, $numRoots, 0), false);
$errorLocations = SplFixedArray::fromArray(array_fill(0, $blockSize, 0), false);
$erasures = array();
// Create parity
$codec->encode($block, $parity);
// Copy parity into test blocks
for ($i = 0; $i < $numRoots; $i++) {
$block[$i + $dataSize] = $parity[$i];
$tBlock[$i + $dataSize] = $parity[$i];
}
// Seed with errors
for ($i = 0; $i < $errors; $i++) {
$errorValue = mt_rand(1, $blockSize);
do {
$errorLocation = mt_rand(0, $blockSize);
} while ($errorLocations[$errorLocation] !== 0);
$errorLocations[$errorLocation] = 1;
if (mt_rand(0, 1)) {
$erasures[] = $errorLocation;
}
$tBlock[$errorLocation] ^= $errorValue;
}
$erasures = SplFixedArray::fromArray($erasures, false);
// Decode the errored block
$foundErrors = $codec->decode($tBlock, $erasures);
if ($errors > 0 && $foundErrors === null) {
$this->assertEquals($block, $tBlock, 'Decoder failed to correct errors');
}
$this->assertEquals($errors, $foundErrors, 'Found errors do not equal expected errors');
for ($i = 0; $i < $foundErrors; $i++) {
if ($errorLocations[$erasures[$i]] === 0) {
$this->fail(sprintf('Decoder indicates error in location %d without error', $erasures[$i]));
}
}
$this->assertEquals($block, $tBlock, 'Decoder did not correct errors');
}
}
}