Add BITPOS command

Author: SHyx0rmZ

src/Redis.php

@@ -1795,6 +1795,38 @@ public function setRange( $key, $offset, $value ) {}
      */
     public function strlen( $key ) {}
 
+    /**
+     * Return the position of the first bit set to 1 or 0 in a string. The position is returned, thinking of the
+     * string as an array of bits from left to right, where the first byte's most significant bit is at position 0,
+     * the second byte's most significant bit is at position 8, and so forth.
+     * @param   string  $key
+     * @param   int     $bit
+     * @param   int     $start
+     * @param   int     $end
+     * @return  int     The command returns the position of the first bit set to 1 or 0 according to the request.
+     *                  If we look for set bits (the bit argument is 1) and the string is empty or composed of just
+     *                  zero bytes, -1 is returned. If we look for clear bits (the bit argument is 0) and the string
+     *                  only contains bit set to 1, the function returns the first bit not part of the string on the
+     *                  right. So if the string is three bytes set to the value 0xff the command BITPOS key 0 will
+     *                  return 24, since up to bit 23 all the bits are 1. Basically, the function considers the right
+     *                  of the string as padded with zeros if you look for clear bits and specify no range or the
+     *                  start argument only. However, this behavior changes if you are looking for clear bits and
+     *                  specify a range with both start and end. If no clear bit is found in the specified range, the
+     *                  function returns -1 as the user specified a clear range and there are no 0 bits in that range.
+     * @link    http://redis.io/commands/bitpos
+     * @example
+     * <pre>
+     * $redis->set('key', '\xff\xff');
+     * $redis->bitpos('key', 1); // int(0)
+     * $redis->bitpos('key', 1, 1); // int(8)
+     * $redis->bitpos('key', 1, 3); // int(-1)
+     * $redis->bitpos('key', 0); // int(16)
+     * $redis->bitpos('key', 0, 1); // int(16)
+     * $redis->bitpos('key', 0, 1, 5); // int(-1)
+     * </pre>
+     */
+    public function bitpos( $key, $bit, $start = 0, $end = null) {}
+
     /**
      * Return a single bit out of a larger string
      *