static void helper_stop(libxl__egc *egc, libxl__ao_abortable *abrt, int rc)
{
libxl__save_helper_state *shs = CONTAINER_OF(abrt, *shs, abrt);
STATE_AO_GC(shs->ao);
if (!libxl__save_helper_inuse(shs)) {
helper_failed(egc, shs, rc);
return;
}
if (!shs->rc)
shs->rc = rc;
libxl__kill(gc, shs->child.pid, SIGTERM, "save/restore helper");
}
static void helper_done(libxl__egc *egc, libxl__save_helper_state *shs)
{
STATE_AO_GC(shs->ao);
libxl__ao_abortable_deregister(&shs->abrt);
libxl__ev_fd_deregister(gc, &shs->readable);
libxl__carefd_close(shs->pipes[0]); shs->pipes[0] = 0;
libxl__carefd_close(shs->pipes[1]); shs->pipes[1] = 0;
assert(!libxl__save_helper_inuse(shs));
shs->egc = egc;
shs->completion_callback(egc, shs->caller_state,
shs->rc, shs->retval, shs->errnoval);
shs->egc = 0;
}
static void helper_failed(libxl__egc *egc, libxl__save_helper_state *shs,
int rc)
{
STATE_AO_GC(shs->ao);
if (!shs->rc)
shs->rc = rc;
libxl__ev_fd_deregister(gc, &shs->readable);
if (!libxl__save_helper_inuse(shs)) {
helper_done(egc, shs);
return;
}
libxl__kill(gc, shs->child.pid, SIGKILL, "save/restore helper");
}
static void check_all_finished(libxl__egc *egc,
libxl__stream_read_state *stream, int rc)
{
STATE_AO_GC(stream->ao);
/*
* In the case of a failure, the _abort()'s below might cancel
* synchronously on top of us, or asynchronously at a later point.
*
* We must avoid the situation where all _abort() cancel
* synchronously and the completion_callback() gets called twice;
* once by the first error and once by the final stacked abort(),
* both of whom will find that all of the tasks have stopped.
*
* To avoid this problem, any stacked re-entry into this function is
* ineligible to fire the completion callback. The outermost
* instance will take care of completing, once the stack has
* unwound.
*/
if (stream->sync_teardown)
return;
if (!stream->rc && rc) {
/* First reported failure. Tear everything down. */
stream->rc = rc;
stream->sync_teardown = true;
libxl__stream_read_abort(egc, stream, rc);
libxl__save_helper_abort(egc, &stream->shs);
libxl__conversion_helper_abort(egc, &stream->chs, rc);
stream->sync_teardown = false;
}
/* Don't fire the callback until all our parallel tasks have stopped. */
if (libxl__stream_read_inuse(stream) ||
libxl__save_helper_inuse(&stream->shs) ||
libxl__conversion_helper_inuse(&stream->chs))
return;
stream->completion_callback(egc, stream, stream->rc);
}
