Merge pull request #1253 from kaotisk-hund/translate-splice-to-php

Translate splice to php

contrib/php/splice.php

@@ -0,0 +1,89 @@
+<?php
+
+function labelToBits($label) {
+    $out = array();
+    $sections = explode('.', $label);
+    $sections = array_reverse($sections);
+    foreach ($sections as $sec) {
+        $n = hexdec("0x" . $sec);
+        for ($i = 0; $i < 16; $i++) {
+            array_unshift($out, ($n & 1) ? 1 : 0);
+            $n >>= 1;
+        }
+    }
+    return $out;
+}
+
+function bitsToChar(&$array) {
+    $num = 0;
+    for ($i = 0; $i < 4; $i++) {
+        $num |= array_pop($array) << $i;
+    }
+    return dechex($num);
+}
+
+function bitsToLabel(&$array) {
+    $chars = [];
+    for ($i = 0; $i < 16; $i++) {
+        if (($i % 4) === 0) {
+            array_unshift($chars, '.');
+        }
+        array_unshift($chars, bitsToChar($array));
+    }
+    array_pop($chars);
+    return implode('', $chars);
+}
+
+function randLabel () {
+    $out = [];
+    for ($i = 0; $i < 4; $i++) {
+        $x = bin2hex(random_bytes(16));
+        if (strlen($x) < 6) {
+            $i--;
+            continue;
+        }
+        array_push($out, substr($x,strlen($x)-4));
+    }
+
+    return implode('.', $out);
+}
+
+function test() {
+    for ($i = 0; $i < 1000; $i++) {
+        $x = randLabel();
+        if (bitsToLabel(labelToBits($x)) !== $x) {
+            throw new Exception($x);
+        }
+    }
+}
+
+test();
+
+function errorArray () {
+    $out = [];
+    for ($i = 0; $i < 64; $i++) { array_push($out, 1); }
+    return $out;
+};
+
+function splice(&$goHere, $viaHere) {
+    while (array_shift($viaHere) === 0) ;
+    $goHere = array_merge($goHere, $viaHere);
+    while (array_shift($goHere) === 0) ;
+    array_unshift($goHere, 1);
+    if (count($goHere) >= 63) {
+        return errorArray();
+    }
+    while (count($goHere) < 64) {
+        array_unshift($goHere, 0);
+    }
+    return $goHere;
+}
+
+
+if (sizeof($argv) > 2) {
+    $viaHereL = array_pop($argv);
+    $goHereL = array_pop($argv);
+    $result = splice(labelToBits($goHereL), labelToBits($viaHereL));
+    echo bitsToLabel($result) . "\n";
+}
+