code review 5058043: websocket: add mutex to make websocket full-duplex

websocket: add mutex to make websocket full-duplex

One benefit of websocket is that it is full-duplex so that it could
send and receive at the same time.
This CL makes websocket goroutine safe, so user could use websocket
both on goroutine for read and on goroutine for write.

[ukai, 2011-09-20 08:41:26]

Hello golang-dev@googlegroups.com (cc: golang-dev@googlegroups.com),

I'd like you to review this change to
https://go.googlecode.com/hg/

[rsc, 2011-09-20 14:47:42]

I'm confused.  It looks like the websocket code already
allows one goroutine to read at the same time another
goroutine writes.  What this CL seems to do is make it
safe for multiple goroutines to read at the same time,
and also to make it safe for multiple goroutines to write
at the same time.  Is that correct?

Russ

[ukai, 2011-09-21 00:16:28]

On 2011/09/20 14:47:42, rsc wrote:
> I'm confused.  It looks like the websocket code already
> allows one goroutine to read at the same time another
> goroutine writes.  What this CL seems to do is make it
> safe for multiple goroutines to read at the same time,
> and also to make it safe for multiple goroutines to write
> at the same time.  Is that correct?

rio is to make it safe for multiple goroutines to read at the same time.
I'm not sure it would be necessary, because typical usage would be to read on
one goroutine.

wio is to make it safe for one goroutine to read at the same time another
goroutine writes.  Read would cause some writes (such as sending pong message to
response ping message) and each message should be written in atomic (not
interleaved with write on another goroutine).  That's why I added wio in this
CL.

Thanks,
ukai

[rsc, 2011-09-23 01:39:44]

LGTM

[rsc, 2011-09-23 01:49:57]

*** Submitted as http://code.google.com/p/go/source/detail?r=671d87eec5df ***

websocket: add mutex to make websocket full-duplex

One benefit of websocket is that it is full-duplex so that it could
send and receive at the same time.
This CL makes websocket goroutine safe, so user could use websocket
both on goroutine for read and on goroutine for write.

R=golang-dev, rsc
CC=golang-dev
http://codereview.appspot.com/5058043

Committer: Russ Cox <rsc@golang.org>