tls_buffer_read
if ((ssn = tls_buffer_read(s->s3->handshake_fragment, buf,
return tls_buffer_read(ctx->hs->tls13.quic_read_buffer, buf, n);
ssize_t tls_buffer_read(struct tls_buffer *buf, uint8_t *rbuf, size_t n);
if ((n = tls_buffer_read(buf, rbuf, rwt->read)) !=