SetMtu will reset kcp.buffer, but kcp.snd_buf has last mss segment

[brevin-yoke]

Setting the MTU will change the buffer size, but there might still be segments of the previous MSS size in the kcp.snd_buf. When calling flush for transmission, will causes a panic.
ptr = segment.encode(ptr) copy(ptr, segment.data) ptr = ptr[len(segment.data):]

[brevin-yoke]

In C, the line kcp->buffer = (char*)ikcp_malloc((kcp->mtu + IKCP_OVERHEAD) * 3); allocates a buffer of size (kcp->mtu + IKCP_OVERHEAD) * 3. Why in Go, the logic is buffer size = mtu？

[xtaci]

I could adjust the buffer to use 3x mtu, but if you set mtu to less than 1/3 of the previous mtu, it will still panic.

[xtaci]

41b30e0

[brevin-yoke]

I don't think (mtu + IKCP_OVERHEAD) * 3 is correct. I think it would be better to use mtu * 3 instead.

[xtaci]

kcp->buffer = (char*)ikcp_malloc((kcp->mtu + IKCP_OVERHEAD) * 3);

It's the same as the C version.