getdns/src/extension/libmini_event.c

227 lines
7.8 KiB
C

/**
*
* \file libmini_event.c
* @brief Build in default eventloop extension that uses select.
*
*/
/*
* Copyright (c) 2013, NLnet Labs, Verisign, Inc.
* All rights reserved.
*
* 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 names of the copyright holders 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 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 Verisign, Inc. 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 "extension/libmini_event.h"
#include "context.h"
#include "util-internal.h"
#if defined(SCHED_DEBUG) && SCHED_DEBUG
#include <inttypes.h>
#endif
static void
_getdns_mini_event_cleanup(getdns_eventloop *loop)
{
_getdns_mini_event *ext = (_getdns_mini_event *)loop;
_getdns_event_base_free(ext->base);
}
void
_getdns_mini_event_destroy(_getdns_mini_event *ext)
{
assert(ext);
ext->loop.vmt->cleanup(&ext->loop);
GETDNS_FREE(ext->mf, ext);
}
void _getdns_handle_timeouts(struct _getdns_event_base* base,
struct timeval* now, struct timeval* wait);
int _getdns_handle_select(struct _getdns_event_base* base, struct timeval* wait);
static int
_getdns_mini_event_settime(_getdns_mini_event *ext)
{
if (gettimeofday(&ext->time_tv, NULL) < 0)
return -1;
ext->time_secs = (time_t)ext->time_tv.tv_sec;
return 0;
}
static void
_getdns_mini_event_run(getdns_eventloop *loop)
{
_getdns_mini_event *ext = (_getdns_mini_event *)loop;
struct timeval wait;
if (ext->n_events == 0 || _getdns_mini_event_settime(ext) < 0)
return;
do {
(void) _getdns_handle_timeouts(ext->base, &ext->time_tv, &wait);
if (!ext->n_events)
break;
if (_getdns_handle_select(ext->base, &wait))
break;
} while (ext->n_events);
}
static void
_getdns_mini_event_run_once(getdns_eventloop *loop, int blocking)
{
static struct timeval immediately = { 0, 0 };
_getdns_mini_event *ext = (_getdns_mini_event *)loop;
struct timeval wait;
if (blocking) {
if (_getdns_mini_event_settime(ext) < 0)
return;
_getdns_handle_timeouts(ext->base, &ext->time_tv, &wait);
if (_getdns_handle_select(ext->base, &wait) < 0)
return;
} else if (_getdns_handle_select(ext->base, &immediately) < 0)
return;
_getdns_handle_timeouts(ext->base, &ext->time_tv, &wait);
}
static getdns_return_t
_getdns_mini_event_clear(getdns_eventloop *loop, getdns_eventloop_event *el_ev)
{
getdns_return_t r = GETDNS_RETURN_GOOD;
_getdns_mini_event *ext = (_getdns_mini_event *)loop;
assert(el_ev->ev);
DEBUG_SCHED("1. _getdns_mini_event_clear(loop: %p, el_ev: %p[userarg: %p, r: %p, w: %p, t: %p, ev: %p]); n_events: %d, times: %d\n", loop, el_ev, el_ev->userarg, el_ev->read_cb, el_ev->write_cb, el_ev->timeout_cb, el_ev->ev, (int)ext->n_events, (int)ext->base->times->count);
if (_getdns_event_del(el_ev->ev) != 0)
r = GETDNS_RETURN_GENERIC_ERROR;
GETDNS_FREE(ext->mf, el_ev->ev);
el_ev->ev = NULL;
ext->n_events--;
DEBUG_SCHED("2. %d <- _getdns_mini_event_clear(loop: %p, el_ev: %p[userarg: %p, r: %p, w: %p, t: %p, ev: %p]); n_events: %d, times: %d\n", r, loop, el_ev, el_ev->userarg, el_ev->read_cb, el_ev->write_cb, el_ev->timeout_cb, el_ev->ev, (int)ext->n_events, (int)ext->base->times->count);
return r;
}
static void
_getdns_mini_event_callback(int fd, short bits, void *arg)
{
getdns_eventloop_event *el_ev = (getdns_eventloop_event *)arg;
DEBUG_SCHED("1. _getdns_mini_event_callback(fd: %d, bits: %d, el_ev: %p[userarg: %p, r: %p, w: %p, t: %p, ev: %p])\n", fd, (int)bits, el_ev, el_ev->userarg, el_ev->read_cb, el_ev->write_cb, el_ev->timeout_cb, el_ev->ev);
if (bits & EV_READ) {
assert(el_ev->read_cb);
el_ev->read_cb(el_ev->userarg);
} else if (bits & EV_WRITE) {
assert(el_ev->write_cb);
el_ev->write_cb(el_ev->userarg);
} else if (bits & EV_TIMEOUT) {
assert(el_ev->timeout_cb);
el_ev->timeout_cb(el_ev->userarg);
} else
assert(ASSERT_UNREACHABLE);
}
static getdns_return_t
_getdns_mini_event_schedule(getdns_eventloop *loop,
int fd, uint64_t timeout, getdns_eventloop_event *el_ev)
{
_getdns_mini_event *ext = (_getdns_mini_event *)loop;
struct _getdns_event *my_ev;
struct timeval tv = { timeout / 1000, (timeout % 1000) * 1000 };
assert(el_ev);
assert(!(el_ev->read_cb || el_ev->write_cb) || fd >= 0);
assert( el_ev->read_cb || el_ev->write_cb || el_ev->timeout_cb);
if (!(my_ev = GETDNS_MALLOC(ext->mf, struct _getdns_event)))
return GETDNS_RETURN_MEMORY_ERROR;
el_ev->ev = my_ev;
DEBUG_SCHED("1. _getdns_mini_event_schedule(loop: %p, fd: %d, timeout: %"PRId64", el_ev: %p[userarg: %p, r: %p, w: %p, t: %p, ev: %p]); n_events: %d\n", loop, fd, timeout, el_ev, el_ev->userarg, el_ev->read_cb, el_ev->write_cb, el_ev->timeout_cb, el_ev->ev, (int)ext->n_events);
_getdns_event_set(my_ev, fd, (
(el_ev->read_cb ? EV_READ|EV_PERSIST : 0) |
(el_ev->write_cb ? EV_WRITE|EV_PERSIST : 0) |
(el_ev->timeout_cb ? EV_TIMEOUT : 0)),
_getdns_mini_event_callback, el_ev);
if (_getdns_mini_event_settime(ext))
goto error;
(void) _getdns_event_base_set(ext->base, my_ev);
if (_getdns_event_add(my_ev, el_ev->timeout_cb ? &tv : NULL))
goto error;
ext->n_events++;
DEBUG_SCHED("2. _getdns_mini_event_schedule(loop: %p, fd: %d, timeout: %"PRId64", el_ev: %p[userarg: %p, r: %p, w: %p, t: %p, ev: %p]); n_events: %d\n", loop, fd, timeout, el_ev, el_ev->userarg, el_ev->read_cb, el_ev->write_cb, el_ev->timeout_cb, el_ev->ev, (int)ext->n_events);
return GETDNS_RETURN_GOOD;
error:
GETDNS_FREE(ext->mf, my_ev);
el_ev->ev = NULL;
DEBUG_SCHED("3. _getdns_mini_event_schedule(loop: %p, fd: %d, timeout: %"PRId64", el_ev: %p[userarg: %p, r: %p, w: %p, t: %p, ev: %p]); n_events: %d\n", loop, fd, timeout, el_ev, el_ev->userarg, el_ev->read_cb, el_ev->write_cb, el_ev->timeout_cb, el_ev->ev, (int)ext->n_events);
return GETDNS_RETURN_GENERIC_ERROR;
}
getdns_return_t
_getdns_mini_event_init(getdns_context *context, _getdns_mini_event *ext)
{
static getdns_eventloop_vmt _getdns_mini_event_vmt = {
_getdns_mini_event_cleanup,
_getdns_mini_event_schedule,
_getdns_mini_event_clear,
_getdns_mini_event_run,
_getdns_mini_event_run_once
};
if (!context)
return GETDNS_RETURN_BAD_CONTEXT;
if (!ext)
return GETDNS_RETURN_INVALID_PARAMETER;
ext->n_events = 0;
ext->loop.vmt = &_getdns_mini_event_vmt;
ext->base = _getdns_event_init(&ext->time_secs, &ext->time_tv);
if (!ext->base)
return GETDNS_RETURN_MEMORY_ERROR;
ext->mf = context->mf;
return GETDNS_RETURN_GOOD;
}
getdns_return_t
_getdns_mini_event_create(getdns_context *context, _getdns_mini_event **ext)
{
if (!context) return GETDNS_RETURN_BAD_CONTEXT;
if (!ext) return GETDNS_RETURN_INVALID_PARAMETER;
*ext = GETDNS_MALLOC(context->mf, _getdns_mini_event);
return _getdns_mini_event_init(context, *ext);
}