/**
* Read 64-bit unsiged integer to $var. If the buffer has less than 8 bytes,
* return false. Advance buffer with consumed bytes.
* @param $var.
*/
public function readLittleEndian64(&$var)
{
$data = null;
if (!$this->readRaw(4, $data)) {
return false;
}
$low = unpack('V', $data)[1];
if (!$this->readRaw(4, $data)) {
return false;
}
$high = unpack('V', $data)[1];
$var = Uint64::newValue($high, $low);
return true;
}
public static function zigZagEncode64($int64)
{
$a = $int64->copy()->leftShift(1);
$b = $int64->copy()->rightShift(63);
$result = $a->bitXor($b);
$uint64 = Uint64::newValue($result->high, $result->low);
return $uint64;
}
public function testZigZagEncodeDecode()
{
$this->assertSame(0, GPBWire::zigZagEncode32(0));
$this->assertSame(1, GPBWire::zigZagEncode32(-1));
$this->assertSame(2, GPBWire::zigZagEncode32(1));
$this->assertSame(3, GPBWire::zigZagEncode32(-2));
$this->assertSame(0x7ffffffe, GPBWire::zigZagEncode32(0x3fffffff));
$this->assertSame(0x7fffffff, GPBWire::zigZagEncode32(0xc0000000));
$this->assertSame(-2, GPBWire::zigZagEncode32(0x7fffffff));
$this->assertSame(-1, GPBWire::zigZagEncode32(0x80000000));
$this->assertSame(0, GPBWire::zigZagDecode32(0));
$this->assertSame(-1, GPBWire::zigZagDecode32(1));
$this->assertSame(1, GPBWire::zigZagDecode32(2));
$this->assertSame(-2, GPBWire::zigZagDecode32(3));
$this->assertSame(0x3fffffff, GPBWire::zigZagDecode32(0x7ffffffe));
$this->assertSame(-1073741824, GPBWire::zigZagDecode32(0x7fffffff));
$this->assertSame(0x7fffffff, GPBWire::zigZagDecode32(0xfffffffe));
$this->assertSame(-2147483648, GPBWire::zigZagDecode32(0xffffffff));
$this->assertEquals(GPBUtil::Uint64(0), GPBWire::zigZagEncode64(GPBUtil::Int64(0)));
$this->assertEquals(GPBUtil::Uint64(1), GPBWire::zigZagEncode64(GPBUtil::Int64(-1)));
$this->assertEquals(GPBUtil::Uint64(2), GPBWire::zigZagEncode64(GPBUtil::Int64(1)));
$this->assertEquals(GPBUtil::Uint64(3), GPBWire::zigZagEncode64(GPBUtil::Int64(-2)));
$this->assertEquals(GPBUtil::Uint64(0x7ffffffe), GPBWire::zigZagEncode64(GPBUtil::Int64(0x3fffffff)));
$this->assertEquals(GPBUtil::Uint64(0x7fffffff), GPBWire::zigZagEncode64(GPBUtil::Int64(1.844674407263581E+19)));
$this->assertEquals(GPBUtil::Uint64(0xfffffffe), GPBWire::zigZagEncode64(GPBUtil::Int64(0x7fffffff)));
$this->assertEquals(GPBUtil::Uint64(0xffffffff), GPBWire::zigZagEncode64(GPBUtil::Int64(1.8446744071562068E+19)));
$this->assertEquals(Uint64::newValue(4294967295, 4294967294), GPBWire::zigZagEncode64(GPBUtil::Int64(0x7fffffffffffffff)));
$this->assertEquals(Uint64::newValue(4294967295, 4294967295), GPBWire::zigZagEncode64(GPBUtil::Int64(9.223372036854776E+18)));
$this->assertEquals(GPBUtil::Int64(0), GPBWire::zigZagDecode64(GPBUtil::Uint64(0)));
$this->assertEquals(GPBUtil::Int64(-1), GPBWire::zigZagDecode64(GPBUtil::Uint64(1)));
$this->assertEquals(GPBUtil::Int64(1), GPBWire::zigZagDecode64(GPBUtil::Uint64(2)));
$this->assertEquals(GPBUtil::Int64(-2), GPBWire::zigZagDecode64(GPBUtil::Uint64(3)));
// Round trip
$this->assertSame(0, GPBWire::zigZagDecode32(GPBWire::zigZagEncode32(0)));
$this->assertSame(1, GPBWire::zigZagDecode32(GPBWire::zigZagEncode32(1)));
$this->assertSame(-1, GPBWire::zigZagDecode32(GPBWire::zigZagEncode32(-1)));
$this->assertSame(14927, GPBWire::zigZagDecode32(GPBWire::zigZagEncode32(14927)));
$this->assertSame(-3612, GPBWire::zigZagDecode32(GPBWire::zigZagEncode32(-3612)));
}