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/* nbdkit
* Copyright Red Hat
*
* 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 Red Hat nor the names of its contributors may be
* used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY RED HAT 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 RED HAT 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 <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
#include <time.h>
#include <assert.h>
#include "internal.h"
#ifdef HAVE_TIMEOUT_OPTION
#include <sys/socket.h>
static void
connection_timeout (union sigval si)
{
struct connection *conn = si.sival_ptr;
assert (conn != NULL);
debug ("connection timed out");
/* Note this is called asynchronously from a different thread,
* making it difficult to do this safely. The theory here is that
* since all connection operations are protected by a lock, we'll
* take that lock and check that conn->magic is valid (to ensure it
* hasn't been freed already). However we still must do the minimum
* possible, since raw socket or gnutls operations may be taking
* place simultaneously. The safest seems to be just to call
* shutdown(2) on the socket. Calling close(2) is less safe as it
* might cause fd reuse.
*/
lock_connection ();
if (conn->magic == CONN_MAGIC &&
conn->timer_set &&
conn->status == STATUS_ACTIVE &&
conn->sockout >= 0) {
shutdown (conn->sockout, SHUT_RDWR);
conn->status = STATUS_DEAD;
}
unlock_connection ();
}
int
start_timeout (struct connection *conn)
{
if (timeout_secs == 0 && timeout_nsecs == 0)
return 0;
struct sigevent sev = {
.sigev_notify = SIGEV_THREAD,
.sigev_value.sival_ptr = conn,
.sigev_notify_function = connection_timeout,
};
struct itimerspec its = {
.it_value.tv_sec = timeout_secs,
.it_value.tv_nsec = timeout_nsecs,
.it_interval.tv_sec = 0, /* 0 = don't repeat */
.it_interval.tv_nsec = 0,
};
if (timer_create (CLOCK_MONOTONIC, &sev, &conn->timer) == -1) {
nbdkit_error ("timeout: timer_create: %m");
return -1;
}
if (timer_settime (conn->timer, 0, &its, NULL) == -1) {
nbdkit_error ("timeout: timer_settime: %m");
timer_delete (conn->timer);
return -1;
}
/* timer_t is actually a void * in glibc, but there seems to be no
* guarantee that '0' means "no timer" (eg. if it was an integral
* type in a different implementation). Therefore record that we
* set it and will need to delete it later.
*/
conn->timer_set = true;
return 0;
}
void
cancel_timeout (struct connection *conn)
{
if (timeout_secs == 0 && timeout_nsecs == 0)
return;
if (conn->timer_set) {
timer_delete (conn->timer);
conn->timer_set = false;
}
}
#else /* !HAVE_TIMEOUT_OPTION */
int
start_timeout (struct connection *conn)
{
return 0;
}
void
cancel_timeout (struct connection *conn)
{
return;
}
#endif /* !HAVE_TIMEOUT_OPTION */
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