What is the right way to close TCP connections?

[Egor Egorov]

Hello.

Suppose I did uv_write() and them immediately uv_close(). Will libuv wait
for all written data to be actually sent? For how long?

In general, what is the best way to close tcp connection given that I don't
want to read anything from it anymore but I want to make sure that's it's
properly written?

[Saúl Ibarra Corretgé]

Hi,

Post by Egor Egorov
Hello.
Suppose I did uv_write() and them immediately uv_close(). Will libuv
wait for all written data to be actually sent? For how long?

No. All pending requests will be cancelled and the write callback will
be called with UV_ECANCELLED status code.

Post by Egor Egorov
In general, what is the best way to close tcp connection given that I
don't want to read anything from it anymore but I want to make sure
that's it's properly written?

Call uv_shutdown and on the shutdown callback uv_close the handle.


Cheers,
--
Saúl Ibarra Corretgé
http://bettercallsaghul.com

[Egor Egorov]

So I was right implementing uv_shutdown(). :) Thanks.

Does this look right?


void onConnectionShutdown(uv_shutdown_t* req, int status) {
if (!uv_is_closing((uv_handle_t*) req->handle)) {
uv_close((uv_handle_t*) req->handle, (uv_close_cb) free);
}
free(req);
}

...

size_t _write_queue_size = ((uv_stream_t *)connection)->write_queue_size;

if (uv_is_writable((uv_stream_t *)connection) && _write_queue_size > 0) {
uv_shutdown_t *shutdownReq = malloc(sizeof(uv_shutdown_t));
uv_shutdown(shutdownReq, (uv_stream_t *) connection, onConnectionShutdown);
} else {
uv_close((uv_handle_t*) connection, (uv_close_cb) free);
}

Post by Saúl Ibarra Corretgé
Hi,

Post by Egor Egorov
Hello.
Suppose I did uv_write() and them immediately uv_close(). Will libuv
wait for all written data to be actually sent? For how long?

No. All pending requests will be cancelled and the write callback will
be called with UV_ECANCELLED status code.

Post by Egor Egorov
In general, what is the best way to close tcp connection given that I
don't want to read anything from it anymore but I want to make sure
that's it's properly written?

Call uv_shutdown and on the shutdown callback uv_close the handle.
Cheers,
--
Saￜl Ibarra Corretgￜ
http://bettercallsaghul.com

[Saúl Ibarra Corretgé]

Post by Egor Egorov
So I was right implementing uv_shutdown(). :) Thanks.
Does this look right?
void onConnectionShutdown(uv_shutdown_t* req, int status) {
if (!uv_is_closing((uv_handle_t*) req->handle)) {

Hum, so chances are you call close before shutdown actually happens?
Either way I'd just call uv_close with free as the callback in case it
was not closing already when the shutdown callback fires. If it was
already closing, don't do anything, the close callback will eventually fire.

Post by Egor Egorov
uv_close((uv_handle_t*) req->handle, (uv_close_cb) free);
}
free(req);
}
...
size_t _write_queue_size = ((uv_stream_t *)connection)->write_queue_size;
if (uv_is_writable((uv_stream_t *)connection) && _write_queue_size > 0) {
uv_shutdown_t *shutdownReq = malloc(sizeof(uv_shutdown_t));
uv_shutdown(shutdownReq, (uv_stream_t *) connection, onConnectionShutdown);
} else {
uv_close((uv_handle_t*) connection, (uv_close_cb) free);
}
Hi,

Post by Egor Egorov
Hello.
Suppose I did uv_write() and them immediately uv_close(). Will libuv
wait for all written data to be actually sent? For how long?

No. All pending requests will be cancelled and the write callback will
be called with UV_ECANCELLED status code.

Post by Egor Egorov
In general, what is the best way to close tcp connection given

that I

Post by Egor Egorov
don't want to read anything from it anymore but I want to make sure
that's it's properly written?

Call uv_shutdown and on the shutdown callback uv_close the handle.
Cheers,
--
Sa�l Ibarra Corretg�
http://bettercallsaghul.com
--
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--
Saúl Ibarra Corretgé
http://bettercallsaghul.com

[Egor Egorov]

yeah, this check in onShutdown callback is clearly redundant; perhaps it
was put there "just in case". Otherwise the code is correct?

Post by Saúl Ibarra Corretgé

Post by Egor Egorov
So I was right implementing uv_shutdown(). :) Thanks.
Does this look right?
void onConnectionShutdown(uv_shutdown_t* req, int status) {
if (!uv_is_closing((uv_handle_t*) req->handle)) {

Hum, so chances are you call close before shutdown actually happens?
Either way I'd just call uv_close with free as the callback in case it
was not closing already when the shutdown callback fires. If it was
already closing, don't do anything, the close callback will eventually fire.

Post by Egor Egorov
uv_close((uv_handle_t*) req->handle, (uv_close_cb) free);
}
free(req);
}
...
size_t _write_queue_size = ((uv_stream_t

*)connection)->write_queue_size;

Post by Egor Egorov
if (uv_is_writable((uv_stream_t *)connection) && _write_queue_size > 0)

{

Post by Egor Egorov
uv_shutdown_t *shutdownReq = malloc(sizeof(uv_shutdown_t));
uv_shutdown(shutdownReq, (uv_stream_t *) connection,

onConnectionShutdown);

Post by Egor Egorov
} else {
uv_close((uv_handle_t*) connection, (uv_close_cb) free);
}
On Friday, October 11, 2013 12:16:33 AM UTC+3, Saￜl Ibarra Corretgￜ
Hi,

Post by Egor Egorov
Hello.
Suppose I did uv_write() and them immediately uv_close(). Will

libuv

Post by Egor Egorov

Post by Egor Egorov
wait for all written data to be actually sent? For how long?

No. All pending requests will be cancelled and the write callback

will

Post by Egor Egorov
be called with UV_ECANCELLED status code.

Post by Egor Egorov
In general, what is the best way to close tcp connection given

that I

Post by Egor Egorov
don't want to read anything from it anymore but I want to make

sure

Post by Egor Egorov

Post by Egor Egorov
that's it's properly written?

Call uv_shutdown and on the shutdown callback uv_close the handle.
Cheers,
--
Saￜl Ibarra Corretgￜ
http://bettercallsaghul.com
--
You received this message because you are subscribed to the Google
Groups "libuv" group.
To unsubscribe from this group and stop receiving emails from it, send
Visit this group at http://groups.google.com/group/libuv.
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--
Saￜl Ibarra Corretgￜ
http://bettercallsaghul.com

[Saúl Ibarra Corretgé]

Post by Egor Egorov
yeah, this check in onShutdown callback is clearly redundant; perhaps
it was put there "just in case". Otherwise the code is correct?

Other than that, looks good to me. Just be careful, because if that if
passes, you'd call free, but that doesn't mean that the close callback
was called, so Bad Things (TM) will happen.

Post by Egor Egorov

Post by Egor Egorov
So I was right implementing uv_shutdown(). :) Thanks.
Does this look right?
void onConnectionShutdown(uv_shutdown_t* req, int status) {
if (!uv_is_closing((uv_handle_t*) req->handle)) {

Hum, so chances are you call close before shutdown actually happens?
Either way I'd just call uv_close with free as the callback in case it
was not closing already when the shutdown callback fires. If it was
already closing, don't do anything, the close callback will eventually fire.

Post by Egor Egorov
uv_close((uv_handle_t*) req->handle, (uv_close_cb) free);
}
free(req);
}
...
size_t _write_queue_size = ((uv_stream_t

*)connection)->write_queue_size;

Post by Egor Egorov
if (uv_is_writable((uv_stream_t *)connection) &&

_write_queue_size > 0) {

Post by Egor Egorov
uv_shutdown_t *shutdownReq = malloc(sizeof(uv_shutdown_t));
uv_shutdown(shutdownReq, (uv_stream_t *) connection,

onConnectionShutdown);

Post by Egor Egorov
} else {
uv_close((uv_handle_t*) connection, (uv_close_cb) free);
}
On Friday, October 11, 2013 12:16:33 AM UTC+3, Sa�l Ibarra
Hi,

Post by Egor Egorov
Hello.
Suppose I did uv_write() and them immediately uv_close().

Will libuv

Post by Egor Egorov

Post by Egor Egorov
wait for all written data to be actually sent? For how long?

No. All pending requests will be cancelled and the write

callback will

Post by Egor Egorov
be called with UV_ECANCELLED status code.

Post by Egor Egorov
In general, what is the best way to close tcp connection

given

Post by Egor Egorov
that I

Post by Egor Egorov
don't want to read anything from it anymore but I want to

make sure

Post by Egor Egorov

Post by Egor Egorov
that's it's properly written?

Call uv_shutdown and on the shutdown callback uv_close the

handle.

Post by Egor Egorov
Cheers,
--
Sa�l Ibarra Corretg�
http://bettercallsaghul.com
--
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Post by Egor Egorov
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Post by Egor Egorov
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Sa�l Ibarra Corretg�
http://bettercallsaghul.com
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--
Saúl Ibarra Corretgé
http://bettercallsaghul.com