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/* Copyright (C) 2010 Simon Josefsson
* Author: Simon Josefsson
*
* Redistribution and use in source and binary forms,
* with or without modification, are permitted provided
* that the following conditions are met:
*
* Redistributions of source code must retain the above
* copyright notice, this list of conditions and the
* following disclaimer.
*
* Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* Neither the name of the copyright holder nor the names
* of any other contributors may be used to endorse or
* promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
* USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*
*/
#include "libssh2_priv.h"
#include "transport.h" /* _libssh2_transport_write */
/* Keep-alive stuff. */
LIBSSH2_API void
libssh2_keepalive_config (LIBSSH2_SESSION *session,
int want_reply,
unsigned interval)
{
if (interval == 1)
session->keepalive_interval = 2;
else
session->keepalive_interval = interval;
session->keepalive_want_reply = want_reply ? 1 : 0;
}
LIBSSH2_API int
libssh2_keepalive_send (LIBSSH2_SESSION *session,
int *seconds_to_next)
{
time_t now;
if (!session->keepalive_interval) {
if (seconds_to_next)
*seconds_to_next = 0;
return 0;
}
now = time (NULL);
if (session->keepalive_last_sent + session->keepalive_interval <= now) {
/* Format is
"SSH_MSG_GLOBAL_REQUEST || 4-byte len || str || want-reply". */
unsigned char keepalive_data[]
= "\x50\x00\x00\x00\x15keepalive@libssh2.orgW";
size_t len = sizeof (keepalive_data) - 1;
int rc;
keepalive_data[len - 1] =
(unsigned char)session->keepalive_want_reply;
rc = _libssh2_transport_send(session, keepalive_data, len, NULL, 0);
/* Silently ignore PACKET_EAGAIN here: if the write buffer is
already full, sending another keepalive is not useful. */
if (rc && rc != LIBSSH2_ERROR_EAGAIN) {
_libssh2_error(session, LIBSSH2_ERROR_SOCKET_SEND,
"Unable to send keepalive message");
return rc;
}
session->keepalive_last_sent = now;
if (seconds_to_next)
*seconds_to_next = session->keepalive_interval;
} else if (seconds_to_next) {
*seconds_to_next = (int) (session->keepalive_last_sent - now)
+ session->keepalive_interval;
}
return 0;
}
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