Merge branch 'denixport-hotfix/rand-int'

HolgerW1 · Mar 5, 2014 · 43f2f86 · 43f2f86
2 parents 4c617fd + 4a5a7df
commit 43f2f86
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Showing 2 changed files with 25 additions and 6 deletions.
diff --git a/library/Zend/Math/Rand.php b/library/Zend/Math/Rand.php
@@ -130,13 +130,21 @@ public static function getInteger($min, $max, $strong = false)
                 'The supplied range is too great to generate'
             );
         }
-        $log    = log($range, 2);
-        $bytes  = (int) ($log / 8) + 1;
-        $bits   = (int) $log + 1;
-        $filter = (int) (1 << $bits) - 1;
+
+        // calculate number of bits required to store range on this machine
+        $r = $range;
+        $bits = 0;
+        while ($r >>= 1) {
+            $bits++;
+        }
+
+        $bits   = (int) max($bits, 1);
+        $bytes  = (int) max(ceil($bits / 8), 1);
+        $filter = (int) ((1 << $bits) - 1);
+
         do {
-            $rnd = hexdec(bin2hex(self::getBytes($bytes, $strong)));
-            $rnd = $rnd & $filter;
+            $rnd  = hexdec(bin2hex(static::getBytes($bytes, $strong)));
+            $rnd &= $filter;
         } while ($rnd > $range);
 
         return ($min + $rnd);

diff --git a/tests/ZendTest/Math/RandTest.php b/tests/ZendTest/Math/RandTest.php
@@ -98,6 +98,17 @@ public function testIntegerRangeFail()
         $rand = Rand::getInteger(100, 0);
     }
 
+    public function testIntegerRangeOverflow()
+    {
+        $values = 0;
+        $cycles = 100;
+        for ($i = 0; $i < $cycles; $i++) {
+            $values += Rand::getInteger(0, PHP_INT_MAX);
+        }
+
+        $this->assertFalse($values === 0);
+    }
+
     public function testRandFloat()
     {
         for ($length = 1; $length < 512; $length++) {