[thirdparty/openssl.git] / doc / man3 / SSL_get_event_timeout.pod

=pod

=head1 NAME

SSL_get_event_timeout - determine when an SSL object next needs to have events
handled

=head1 SYNOPSIS

 #include <openssl/ssl.h>

 int SSL_get_event_timeout(SSL *s, struct timeval *tv, int *is_infinite);

=head1 DESCRIPTION

SSL_get_event_timeout() determines when the SSL object next needs to perform
internal processing due to the passage of time.

All arguments are required; I<tv> and I<is_infinite> must be non-NULL.

Upon the successful return of SSL_get_event_timeout(), one of the following
cases applies:

=over 4

=item

The SSL object has events which need to be handled immediately; The fields of
I<*tv> are set to 0 and I<*is_infinite> is set to 0.

=item

The SSL object has events which need to be handled after some amount of time
(relative to the time at which SSL_get_event_timeout() was called). I<*tv> is
set to the amount of time after which L<SSL_handle_events(3)> should be called
and I<*is_infinite> is set to 0.

=item

There are currently no timer events which require handling in the future. The
value of I<*tv> is unspecified and I<*is_infinite> is set to 1.

=back

This function is currently applicable only to DTLS and QUIC connection SSL
objects. If it is called on any other kind of SSL object, it always outputs
infinity. This is considered a success condition.

For DTLS, this function can be used instead of the older
L<DTLSv1_get_timeout(3)> function. Note that this function differs from
L<DTLSv1_get_timeout(3)> in that the case where no timeout is active is
considered a success condition.

Note that the value output by a call to SSL_get_event_timeout() may change as a
result of other calls to the SSL object.

Once the timeout expires, L<SSL_handle_events(3)> should be called to handle any
internal processing which is due; for more information, see
L<SSL_handle_events(3)>.

Note that SSL_get_event_timeout() supersedes the older L<DTLSv1_get_timeout(3)>
function for all use cases.

If the call to SSL_get_event_timeout() fails, the values of I<*tv> and
I<*is_infinite> may still be changed and their values become unspecified.

=head1 RETURN VALUES

Returns 1 on success and 0 on failure.

=head1 SEE ALSO

L<SSL_handle_events(3)>, L<DTLSv1_get_timeout(3)>, L<ssl(7)>

=head1 HISTORY

The SSL_get_event_timeout() function was added in OpenSSL 3.2.

=head1 COPYRIGHT

Copyright 2022-2023 The OpenSSL Project Authors. All Rights Reserved.

Licensed under the Apache License 2.0 (the "License").  You may not use
this file except in compliance with the License.  You can obtain a copy
in the file LICENSE in the source distribution or at
L<https://www.openssl.org/source/license.html>.

=cut
Commit	Line	Data
c572bed9 HL	1	=pod
	2
	3	=head1 NAME
	4
b626a0f1 HL	5	SSL_get_event_timeout - determine when an SSL object next needs to have events
b626a0f1 HL	6	handled
c572bed9 HL	7
	8	=head1 SYNOPSIS
	9
	10	#include <openssl/ssl.h>
	11
a28ac613	12	int SSL_get_event_timeout(SSL s, struct timeval tv, int *is_infinite);
c572bed9 HL	13
	14	=head1 DESCRIPTION
	15
f8503ede	16	SSL_get_event_timeout() determines when the SSL object next needs to perform
2fff884c	17	internal processing due to the passage of time.
c572bed9	18
a28ac613 HL	19	All arguments are required; I<tv> and I<is_infinite> must be non-NULL.
	20
	21	Upon the successful return of SSL_get_event_timeout(), one of the following
	22	cases applies:
	23
	24	=over 4
	25
	26	=item
	27
b626a0f1 HL	28	The SSL object has events which need to be handled immediately; The fields of
b626a0f1 HL	29	I<tv> are set to 0 and I<is_infinite> is set to 0.
a28ac613 HL	30
	31	=item
	32
	33	The SSL object has events which need to be handled after some amount of time
	34	(relative to the time at which SSL_get_event_timeout() was called). I<*tv> is
	35	set to the amount of time after which L<SSL_handle_events(3)> should be called
	36	and I<*is_infinite> is set to 0.
	37
	38	=item
	39
	40	There are currently no timer events which require handling in the future. The
	41	value of I<tv> is unspecified and I<is_infinite> is set to 1.
	42
	43	=back
c572bed9	44
2fff884c HL	45	This function is currently applicable only to DTLS and QUIC connection SSL
	46	objects. If it is called on any other kind of SSL object, it always outputs
	47	infinity. This is considered a success condition.
	48
8ccc567e HL	49	For DTLS, this function can be used instead of the older
	50	L<DTLSv1_get_timeout(3)> function. Note that this function differs from
	51	L<DTLSv1_get_timeout(3)> in that the case where no timeout is active is
	52	considered a success condition.
	53
f8503ede	54	Note that the value output by a call to SSL_get_event_timeout() may change as a
c572bed9 HL	55	result of other calls to the SSL object.
c572bed9 HL	56
b626a0f1	57	Once the timeout expires, L<SSL_handle_events(3)> should be called to handle any
f8503ede HL	58	internal processing which is due; for more information, see
f8503ede HL	59	L<SSL_handle_events(3)>.
c572bed9	60
f8503ede	61	Note that SSL_get_event_timeout() supersedes the older L<DTLSv1_get_timeout(3)>
8ccc567e HL	62	function for all use cases.
8ccc567e HL	63
a28ac613 HL	64	If the call to SSL_get_event_timeout() fails, the values of I<*tv> and
	65	I<*is_infinite> may still be changed and their values become unspecified.
	66
c572bed9 HL	67	=head1 RETURN VALUES
	68
	69	Returns 1 on success and 0 on failure.
	70
	71	=head1 SEE ALSO
	72
f8503ede	73	L<SSL_handle_events(3)>, L<DTLSv1_get_timeout(3)>, L<ssl(7)>
c572bed9 HL	74
	75	=head1 HISTORY
	76
f8503ede	77	The SSL_get_event_timeout() function was added in OpenSSL 3.2.
c572bed9 HL	78
	79	=head1 COPYRIGHT
	80
da1c088f	81	Copyright 2022-2023 The OpenSSL Project Authors. All Rights Reserved.
c572bed9 HL	82
	83	Licensed under the Apache License 2.0 (the "License"). You may not use
	84	this file except in compliance with the License. You can obtain a copy
	85	in the file LICENSE in the source distribution or at
	86	L<https://www.openssl.org/source/license.html>.
	87
	88	=cut