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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 <stdint.h>
#include <pthread.h>
#include <nbdkit-filter.h>
#include "readahead.h"
#include "cleanup.h"
void *
readahead_thread (void *vp)
{
struct bgthread_ctrl *ctrl = vp;
for (;;) {
struct command cmd;
/* Wait until we are sent at least one command. */
{
ACQUIRE_LOCK_FOR_CURRENT_SCOPE (&ctrl->lock);
while (ctrl->cmds.len == 0)
pthread_cond_wait (&ctrl->cond, &ctrl->lock);
cmd = ctrl->cmds.ptr[0];
command_queue_remove (&ctrl->cmds, 0);
}
switch (cmd.type) {
case CMD_QUIT:
/* Finish processing and exit the thread. */
return NULL;
case CMD_CACHE:
/* Issue .cache (readahead) to underlying plugin. We ignore any
* errors because there's no way to communicate that back to the
* client, and readahead is only advisory.
*/
cmd.next->cache (cmd.next, cmd.count, cmd.offset, 0, NULL);
}
}
}
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