Add WriteBufferPool to Dialer and Upgrader. This field specifies a pool
to use for write operations on a connection. Use of the pool can reduce
memory use when there is a modest write volume over a large number of
connections.
Use larger of hijacked buffer and buffer allocated for connection (if
any) as buffer for building handshake response. This decreases possible
allocations when building the handshake response.
Modify bufio reuse test to call Upgrade instead of the internal
newConnBRW. Move the test from conn_test.go to server_test.go because
it's a serer test.
Update newConn and newConnBRW:
- Move the bufio "hacks" from newConnBRW to separate functions and call
these functions directly from Upgrade.
- Rename newConn to newTestConn and move to conn_test.go. Shorten
argument list to common use case.
- Rename newConnBRW to newConn.
- Add pool code to newConn.
The JSON decoder returns io.EOF when a message is empty or all
whitespace. Convert io.EOF return values from the JSON decoder to
io.ErrUnexpectedEOF so that applications can distinguish between an
error reading the JSON value and the connection closing.
merlin