How to correctly deserialize a message with variable length array?

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I'm receiving some data from serial port and want to deserialize the byte stream I received to a ROS message.

The serial port data contains variable number of elements (elements with same type). So I use variable length array in my ROS message.

For example I have received these bytes in memory:

uint8_t buffer[] = { 0x02, 0x01, 0x01, 0x01, 0x01, 0x02, 0x02, 0x02, 0x02, 0x03, 0x03, 0x03, 0x03, 0x11, 0x11, 0x11, 0x11, 0x12, 0x12, 0x12, 0x12, 0x13, 0x13, 0x13, 0x13 };

Here,

• 0x02 means 2 elements in the variable length array,
• (0x01010101, 0x02020202, 0x03030303) is the first element, this is actually a 3-dimensional point with float type,
• (0x11111111, 0x12121212, 0x13131313) is the second element.

And I'm going to use this message:

uint8 array_size    # will be 0x02
geometry_msgs/Point32[] points    # will be a array with length 2, the first Point32 is (0x01010101, 0x02020202, 0x03030303), and the second one is (0x11111111, 0x12121212, 0x13131313)

It seems the tutorial does not work with variable length array. I checked the code, and there is a serializer for std::vector.

But the deserialization process goes wrong in this function:

// (line 348 of serialization.h)
template<typename Stream>
inline static void read(Stream& stream, VecType& v)
{
    uint32_t len;
    stream.next(len);
    v.resize(len);    // <----
    IteratorType it = v.begin();
    IteratorType end = v.end();
    for (; it != end; ++it)
    {
        stream.next(*it);
    }   
}

It seems the deserializer will change the length of the vector first. But the value of variable len gets very huge and v.resize(len) fails.