Skip to content

HTTPS clone URL

Subversion checkout URL

You can clone with
or
.
Download ZIP
Fetching contributors…

Cannot retrieve contributors at this time

630 lines (543 sloc) 15.375 kB
/*
* Copyright (c) 2002-2007 Niels Provos <provos@citi.umich.edu>
* Copyright (c) 2007-2009 Niels Provos, Nick Mathewson
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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 <sys/types.h>
#ifdef HAVE_CONFIG_H
#include "event-config.h"
#endif
#ifdef _EVENT_HAVE_SYS_TIME_H
#include <sys/time.h>
#endif
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifdef _EVENT_HAVE_STDARG_H
#include <stdarg.h>
#endif
#ifdef WIN32
#include <winsock2.h>
#endif
#include <errno.h>
#include "event2/util.h"
#include "event2/bufferevent.h"
#include "event2/buffer.h"
#include "event2/bufferevent_struct.h"
#include "event2/bufferevent_compat.h"
#include "event2/event.h"
#include "log-internal.h"
#include "mm-internal.h"
#include "bufferevent-internal.h"
#include "util-internal.h"
void
bufferevent_wm_suspend_read(struct bufferevent *bufev)
{
struct bufferevent_private *bufev_private =
EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
BEV_LOCK(bufev);
if (!bufev_private->read_suspended) {
bufev->be_ops->disable(bufev, EV_READ);
bufev_private->read_suspended = 1;
}
BEV_UNLOCK(bufev);
}
void
bufferevent_wm_unsuspend_read(struct bufferevent *bufev)
{
struct bufferevent_private *bufev_private =
EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
BEV_LOCK(bufev);
if (bufev_private->read_suspended) {
bufev_private->read_suspended = 0;
if (bufev->enabled & EV_READ)
bufev->be_ops->enable(bufev, EV_READ);
}
BEV_UNLOCK(bufev);
}
/* Callback to implement watermarks on the input buffer. Only enabled
* if the watermark is set. */
static void
bufferevent_inbuf_wm_cb(struct evbuffer *buf,
const struct evbuffer_cb_info *cbinfo,
void *arg)
{
struct bufferevent *bufev = arg;
size_t size;
size = evbuffer_get_length(buf);
if (cbinfo->n_added > cbinfo->n_deleted) {
/* Data got added. If it put us over the watermark, stop
* reading. */
if (size >= bufev->wm_read.high)
bufferevent_wm_suspend_read(bufev);
} else {
/* Data got removed. If it puts us under the watermark,
stop reading. */
if (size < bufev->wm_read.high)
bufferevent_wm_unsuspend_read(bufev);
}
}
static void
bufferevent_run_deferred_callbacks(struct deferred_cb *_, void *arg)
{
struct bufferevent_private *bufev_private = arg;
struct bufferevent *bufev = &bufev_private->bev;
/* XXXX It would be better to run these without holding the
* bufferevent lock */
BEV_LOCK(bufev);
if (bufev_private->readcb_pending && bufev->readcb) {
bufev_private->readcb_pending = 0;
bufev->readcb(bufev, bufev->cbarg);
}
if (bufev_private->writecb_pending && bufev->writecb) {
bufev_private->writecb_pending = 0;
bufev->writecb(bufev, bufev->cbarg);
}
if (bufev_private->eventcb_pending && bufev->errorcb) {
short what = bufev_private->eventcb_pending;
int err = bufev_private->errno_pending;
bufev_private->eventcb_pending = 0;
bufev_private->errno_pending = 0;
EVUTIL_SET_SOCKET_ERROR(err);
bufev->errorcb(bufev, what, bufev->cbarg);
}
_bufferevent_decref_and_unlock(bufev);
}
void
_bufferevent_run_readcb(struct bufferevent *bufev)
{
/* Requires that we hold the lock and a reference */
struct bufferevent_private *p =
EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
if (p->options & BEV_OPT_DEFER_CALLBACKS) {
p->readcb_pending = 1;
if (!p->deferred.queued) {
bufferevent_incref(bufev);
event_deferred_cb_schedule(
bufev->ev_base, &p->deferred);
}
} else {
bufev->readcb(bufev, bufev->cbarg);
}
}
void
_bufferevent_run_writecb(struct bufferevent *bufev)
{
/* Requires that we hold the lock and a reference */
struct bufferevent_private *p =
EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
if (p->options & BEV_OPT_DEFER_CALLBACKS) {
p->writecb_pending = 1;
if (!p->deferred.queued) {
bufferevent_incref(bufev);
event_deferred_cb_schedule(
bufev->ev_base, &p->deferred);
}
} else {
bufev->writecb(bufev, bufev->cbarg);
}
}
void
_bufferevent_run_eventcb(struct bufferevent *bufev, short what)
{
/* Requires that we hold the lock and a reference */
struct bufferevent_private *p =
EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
if (p->options & BEV_OPT_DEFER_CALLBACKS) {
p->eventcb_pending |= what;
p->errno_pending = EVUTIL_SOCKET_ERROR();
if (!p->deferred.queued) {
bufferevent_incref(bufev);
event_deferred_cb_schedule(
bufev->ev_base, &p->deferred);
}
} else {
bufev->errorcb(bufev, what, bufev->cbarg);
}
}
int
bufferevent_init_common(struct bufferevent_private *bufev_private,
struct event_base *base,
const struct bufferevent_ops *ops,
enum bufferevent_options options)
{
struct bufferevent *bufev = &bufev_private->bev;
if (!bufev->input) {
if ((bufev->input = evbuffer_new()) == NULL)
return -1;
}
if (!bufev->output) {
if ((bufev->output = evbuffer_new()) == NULL) {
evbuffer_free(bufev->input);
return -1;
}
}
bufev_private->refcnt = 1;
bufev->ev_base = base;
/* Disable timeouts. */
evutil_timerclear(&bufev->timeout_read);
evutil_timerclear(&bufev->timeout_write);
bufev->be_ops = ops;
/*
* Set to EV_WRITE so that using bufferevent_write is going to
* trigger a callback. Reading needs to be explicitly enabled
* because otherwise no data will be available.
*/
bufev->enabled = EV_WRITE;
#ifndef _EVENT_DISABLE_THREAD_SUPPORT
if (options & BEV_OPT_THREADSAFE) {
if (bufferevent_enable_locking(bufev, NULL) < 0) {
/* cleanup */
return -1;
}
}
#endif
if (options & BEV_OPT_DEFER_CALLBACKS) {
event_deferred_cb_init(&bufev_private->deferred,
bufferevent_run_deferred_callbacks,
bufev_private);
}
bufev_private->options = options;
return 0;
}
void
bufferevent_setcb(struct bufferevent *bufev,
bufferevent_data_cb readcb, bufferevent_data_cb writecb,
bufferevent_event_cb eventcb, void *cbarg)
{
BEV_LOCK(bufev);
bufev->readcb = readcb;
bufev->writecb = writecb;
bufev->errorcb = eventcb;
bufev->cbarg = cbarg;
BEV_UNLOCK(bufev);
}
struct evbuffer *
bufferevent_get_input(struct bufferevent *bufev)
{
return bufev->input;
}
struct evbuffer *
bufferevent_get_output(struct bufferevent *bufev)
{
return bufev->output;
}
/*
* Returns 0 on success;
* -1 on failure.
*/
int
bufferevent_write(struct bufferevent *bufev, const void *data, size_t size)
{
if (evbuffer_add(bufev->output, data, size) == -1)
return (-1);
return 0;
}
int
bufferevent_write_buffer(struct bufferevent *bufev, struct evbuffer *buf)
{
if (evbuffer_add_buffer(bufev->output, buf) == -1)
return (-1);
return 0;
}
size_t
bufferevent_read(struct bufferevent *bufev, void *data, size_t size)
{
return (evbuffer_remove(bufev->input, data, size));
}
int
bufferevent_read_buffer(struct bufferevent *bufev, struct evbuffer *buf)
{
return (evbuffer_add_buffer(buf, bufev->input));
}
int
bufferevent_enable(struct bufferevent *bufev, short event)
{
struct bufferevent_private *bufev_private =
EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
short impl_events = event;
int r = 0;
BEV_LOCK(bufev);
if (bufev_private->read_suspended)
impl_events &= ~EV_READ;
bufev->enabled |= event;
if (bufev->be_ops->enable(bufev, impl_events) < 0)
r = -1;
BEV_UNLOCK(bufev);
return r;
}
void
bufferevent_set_timeouts(struct bufferevent *bufev,
const struct timeval *tv_read,
const struct timeval *tv_write)
{
BEV_LOCK(bufev);
if (tv_read) {
bufev->timeout_read = *tv_read;
} else {
evutil_timerclear(&bufev->timeout_read);
}
if (tv_write) {
bufev->timeout_write = *tv_write;
} else {
evutil_timerclear(&bufev->timeout_write);
}
if (bufev->be_ops->adj_timeouts)
bufev->be_ops->adj_timeouts(bufev);
BEV_UNLOCK(bufev);
}
/* Obsolete; use bufferevent_set_timeouts */
void
bufferevent_settimeout(struct bufferevent *bufev,
int timeout_read, int timeout_write)
{
struct timeval tv_read, tv_write;
struct timeval *ptv_read = NULL, *ptv_write = NULL;
memset(&tv_read, 0, sizeof(tv_read));
memset(&tv_write, 0, sizeof(tv_write));
if (timeout_read) {
tv_read.tv_sec = timeout_read;
ptv_read = &tv_read;
}
if (timeout_write) {
tv_write.tv_sec = timeout_write;
ptv_write = &tv_write;
}
bufferevent_set_timeouts(bufev, ptv_read, ptv_write);
}
int
bufferevent_disable(struct bufferevent *bufev, short event)
{
int r = 0;
BEV_LOCK(bufev);
bufev->enabled &= ~event;
if (bufev->be_ops->disable(bufev, event) < 0)
r = -1;
BEV_UNLOCK(bufev);
return r;
}
/*
* Sets the water marks
*/
void
bufferevent_setwatermark(struct bufferevent *bufev, short events,
size_t lowmark, size_t highmark)
{
struct bufferevent_private *bufev_private =
EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
BEV_LOCK(bufev);
if (events & EV_WRITE) {
bufev->wm_write.low = lowmark;
bufev->wm_write.high = highmark;
}
if (events & EV_READ) {
bufev->wm_read.low = lowmark;
bufev->wm_read.high = highmark;
if (highmark) {
/* There is now a new high-water mark for read.
enable the callback if needed, and see if we should
suspend/bufferevent_wm_unsuspend. */
if (bufev_private->read_watermarks_cb == NULL) {
bufev_private->read_watermarks_cb =
evbuffer_add_cb(bufev->input,
bufferevent_inbuf_wm_cb,
bufev);
}
evbuffer_cb_set_flags(bufev->input,
bufev_private->read_watermarks_cb,
EVBUFFER_CB_ENABLED);
if (evbuffer_get_length(bufev->input) > highmark)
bufferevent_wm_suspend_read(bufev);
else if (evbuffer_get_length(bufev->input) < highmark)
bufferevent_wm_unsuspend_read(bufev);
} else {
/* There is now no high-water mark for read. */
if (bufev_private->read_watermarks_cb)
evbuffer_cb_clear_flags(bufev->input,
bufev_private->read_watermarks_cb,
EVBUFFER_CB_ENABLED);
bufferevent_wm_unsuspend_read(bufev);
}
}
BEV_UNLOCK(bufev);
}
int
bufferevent_flush(struct bufferevent *bufev,
short iotype,
enum bufferevent_flush_mode mode)
{
int r = -1;
BEV_LOCK(bufev);
if (bufev->be_ops->flush)
r = bufev->be_ops->flush(bufev, iotype, mode);
BEV_UNLOCK(bufev);
return r;
}
void
_bufferevent_incref_and_lock(struct bufferevent *bufev)
{
struct bufferevent_private *bufev_private =
BEV_UPCAST(bufev);
BEV_LOCK(bufev);
++bufev_private->refcnt;
}
void
_bufferevent_decref_and_unlock(struct bufferevent *bufev)
{
struct bufferevent_private *bufev_private =
EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
if (--bufev_private->refcnt) {
BEV_UNLOCK(bufev);
return;
}
/* Clean up the shared info */
if (bufev->be_ops->destruct)
bufev->be_ops->destruct(bufev);
/* evbuffer will free the callbacks */
evbuffer_free(bufev->input);
evbuffer_free(bufev->output);
BEV_UNLOCK(bufev);
if (bufev_private->own_lock)
EVTHREAD_FREE_LOCK(bufev_private->lock);
/* Free the actual allocated memory. */
mm_free(bufev - bufev->be_ops->mem_offset);
}
void
bufferevent_free(struct bufferevent *bufev)
{
BEV_LOCK(bufev);
_bufferevent_decref_and_unlock(bufev);
}
void
bufferevent_incref(struct bufferevent *bufev)
{
struct bufferevent_private *bufev_private =
EVUTIL_UPCAST(bufev, struct bufferevent_private, bev);
BEV_LOCK(bufev);
++bufev_private->refcnt;
BEV_UNLOCK(bufev);
}
int
bufferevent_enable_locking(struct bufferevent *bufev, void *lock)
{
#ifdef _EVENT_DISABLE_THREAD_SUPPORT
return -1;
#else
if (BEV_UPCAST(bufev)->lock)
return -1;
if (!lock) {
EVTHREAD_ALLOC_LOCK(lock);
if (!lock)
return -1;
BEV_UPCAST(bufev)->lock = lock;
BEV_UPCAST(bufev)->own_lock = 1;
} else {
BEV_UPCAST(bufev)->lock = lock;
BEV_UPCAST(bufev)->own_lock = 0;
}
evbuffer_enable_locking(bufev->input, lock);
evbuffer_enable_locking(bufev->output, lock);
return 0;
#endif
}
int
bufferevent_setfd(struct bufferevent *bev, evutil_socket_t fd)
{
union bufferevent_ctrl_data d;
int res = -1;
d.fd = fd;
BEV_LOCK(bev);
if (bev->be_ops->ctrl)
res = bev->be_ops->ctrl(bev, BEV_CTRL_SET_FD, &d);
BEV_UNLOCK(bev);
return res;
}
evutil_socket_t
bufferevent_getfd(struct bufferevent *bev)
{
union bufferevent_ctrl_data d;
int res = -1;
d.fd = -1;
BEV_LOCK(bev);
if (bev->be_ops->ctrl)
res = bev->be_ops->ctrl(bev, BEV_CTRL_GET_FD, &d);
BEV_UNLOCK(bev);
return (res<0) ? -1 : d.fd;
}
struct bufferevent *
bufferevent_get_underlying(struct bufferevent *bev)
{
union bufferevent_ctrl_data d;
int res = -1;
d.ptr = NULL;
BEV_LOCK(bev);
if (bev->be_ops->ctrl)
res = bev->be_ops->ctrl(bev, BEV_CTRL_GET_UNDERLYING, &d);
BEV_UNLOCK(bev);
return (res<0) ? NULL : d.ptr;
}
static void
bufferevent_generic_read_timeout_cb(evutil_socket_t fd, short event, void *ctx)
{
struct bufferevent *bev = ctx;
_bufferevent_incref_and_lock(bev);
_bufferevent_run_eventcb(bev, BEV_EVENT_TIMEOUT|BEV_EVENT_READING);
_bufferevent_decref_and_unlock(bev);
}
static void
bufferevent_generic_write_timeout_cb(evutil_socket_t fd, short event, void *ctx)
{
struct bufferevent *bev = ctx;
_bufferevent_incref_and_lock(bev);
_bufferevent_run_eventcb(bev, BEV_EVENT_TIMEOUT|BEV_EVENT_WRITING);
_bufferevent_decref_and_unlock(bev);
}
void
_bufferevent_init_generic_timeout_cbs(struct bufferevent *bev)
{
evtimer_assign(&bev->ev_read, bev->ev_base,
bufferevent_generic_read_timeout_cb, bev);
evtimer_assign(&bev->ev_read, bev->ev_base,
bufferevent_generic_write_timeout_cb, bev);
}
void
_bufferevent_del_generic_timeout_cbs(struct bufferevent *bev)
{
event_del(&bev->ev_read);
event_del(&bev->ev_write);
}
void
_bufferevent_generic_adj_timeouts(struct bufferevent *bev)
{
const short enabled = bev->enabled;
if ((enabled & EV_READ) && evutil_timerisset(&bev->timeout_read))
event_add(&bev->ev_read, &bev->timeout_read);
else
event_del(&bev->ev_read);
if ((enabled & EV_WRITE) && evutil_timerisset(&bev->timeout_write))
event_add(&bev->ev_write, &bev->timeout_write);
else
event_del(&bev->ev_write);
}
Jump to Line
Something went wrong with that request. Please try again.