minor #40009 [Uid] improve logic in BinaryUtil::timeToFloat() (nicolas-grekas)

nicolas-grekas · nicolas-grekas · commit bda55f073a43 · 2021-01-27T21:51:43.000+01:00
This PR was merged into the 5.2 branch. Discussion ---------- [Uid] improve logic in BinaryUtil::timeToFloat() | Q | A | ------------- | --- | Branch? | 5.2 | Bug fix? | no | New feature? | no | Deprecations? | no | Tickets | - | License | MIT | Doc PR | - Commits ------- 8555824 [Uid] improve logic in BinaryUtil::timeToFloat()
diff --git a/src/Symfony/Component/Uid/BinaryUtil.php b/src/Symfony/Component/Uid/BinaryUtil.php
@@ -40,6 +40,8 @@ class BinaryUtil
     // 0x01b21dd213814000 is the number of 100-ns intervals between the
     // UUID epoch 1582-10-15 00:00:00 and the Unix epoch 1970-01-01 00:00:00.
     private const TIME_OFFSET_INT = 0x01b21dd213814000;
+    private const TIME_OFFSET_BIN = "\x01\xb2\x1d\xd2\x13\x81\x40\x00";
+    private const TIME_OFFSET_COM1 = "\xfe\x4d\xe2\x2d\xec\x7e\xbf\xff";
     private const TIME_OFFSET_COM2 = "\xfe\x4d\xe2\x2d\xec\x7e\xc0\x00";
 
     public static function toBase(string $bytes, array $map): string
@@ -114,20 +116,24 @@ public static function add(string $a, string $b): string
         return $a;
     }
 
+    /**
+     * @param string $time Count of 100-nanosecond intervals since the UUID epoch 1582-10-15 00:00:00 in hexadecimal
+     */
     public static function timeToFloat(string $time): float
     {
         if (\PHP_INT_SIZE >= 8) {
-            return (hexdec($time) - self::TIME_OFFSET_INT) / 10000000;
-        }
-
-        $time = str_pad(hex2bin($time), 8, "\0", \STR_PAD_LEFT);
-        $time = self::add($time, self::TIME_OFFSET_COM2);
-
-        if ($time >= self::TIME_OFFSET_COM2) {
-            $time = -1 * (self::toBase($time ^ "\xff\xff\xff\xff\xff\xff\xff\xff", self::BASE10) + 1);
+            $time = hexdec($time) - self::TIME_OFFSET_INT;
         } else {
-            $time[0] = $time[0] & "\x7F";
-            $time = self::toBase($time, self::BASE10);
+            $time = str_pad(hex2bin($time), 8, "\0", \STR_PAD_LEFT);
+
+            if (self::TIME_OFFSET_BIN <= $time) {
+                $time = self::add($time, self::TIME_OFFSET_COM2);
+                $time[0] = $time[0] & "\x7F";
+                $time = self::toBase($time, self::BASE10);
+            } else {
+                $time = self::add($time, self::TIME_OFFSET_COM1);
+                $time = '-'.self::toBase($time ^ "\xff\xff\xff\xff\xff\xff\xff\xff", self::BASE10);
+            }
         }
 
         return $time / 10000000;
