monero/external/unbound/util/mini_event.c
Erik de Castro Lopo a85b5759f3 Upgrade unbound library
These files were pulled from the 1.6.3 release tarball.

This new version builds against OpenSSL version 1.1 which will be
the default in the new Debian Stable which is due to be released
RealSoonNow (tm).
2017-06-17 23:04:00 +10:00

391 lines
9.7 KiB
C

/*
* mini_event.c - implementation of part of libevent api, portably.
*
* Copyright (c) 2007, NLnet Labs. All rights reserved.
*
* This software is open source.
*
* 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 the NLNET LABS 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 THE COPYRIGHT
* HOLDER 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.
*
*/
/**
* \file
* fake libevent implementation. Less broad in functionality, and only
* supports select(2).
*/
#include "config.h"
#ifdef HAVE_TIME_H
#include <time.h>
#endif
#include <sys/time.h>
#if defined(USE_MINI_EVENT) && !defined(USE_WINSOCK)
#include <signal.h>
#include "util/mini_event.h"
#include "util/fptr_wlist.h"
/** compare events in tree, based on timevalue, ptr for uniqueness */
int mini_ev_cmp(const void* a, const void* b)
{
const struct event *e = (const struct event*)a;
const struct event *f = (const struct event*)b;
if(e->ev_timeout.tv_sec < f->ev_timeout.tv_sec)
return -1;
if(e->ev_timeout.tv_sec > f->ev_timeout.tv_sec)
return 1;
if(e->ev_timeout.tv_usec < f->ev_timeout.tv_usec)
return -1;
if(e->ev_timeout.tv_usec > f->ev_timeout.tv_usec)
return 1;
if(e < f)
return -1;
if(e > f)
return 1;
return 0;
}
/** set time */
static int
settime(struct event_base* base)
{
if(gettimeofday(base->time_tv, NULL) < 0) {
return -1;
}
#ifndef S_SPLINT_S
*base->time_secs = (time_t)base->time_tv->tv_sec;
#endif
return 0;
}
/** create event base */
void *event_init(time_t* time_secs, struct timeval* time_tv)
{
struct event_base* base = (struct event_base*)malloc(
sizeof(struct event_base));
if(!base)
return NULL;
memset(base, 0, sizeof(*base));
base->time_secs = time_secs;
base->time_tv = time_tv;
if(settime(base) < 0) {
event_base_free(base);
return NULL;
}
base->times = rbtree_create(mini_ev_cmp);
if(!base->times) {
event_base_free(base);
return NULL;
}
base->capfd = MAX_FDS;
#ifdef FD_SETSIZE
if((int)FD_SETSIZE < base->capfd)
base->capfd = (int)FD_SETSIZE;
#endif
base->fds = (struct event**)calloc((size_t)base->capfd,
sizeof(struct event*));
if(!base->fds) {
event_base_free(base);
return NULL;
}
base->signals = (struct event**)calloc(MAX_SIG, sizeof(struct event*));
if(!base->signals) {
event_base_free(base);
return NULL;
}
#ifndef S_SPLINT_S
FD_ZERO(&base->reads);
FD_ZERO(&base->writes);
#endif
return base;
}
/** get version */
const char *event_get_version(void)
{
return "mini-event-"PACKAGE_VERSION;
}
/** get polling method, select */
const char *event_get_method(void)
{
return "select";
}
/** call timeouts handlers, and return how long to wait for next one or -1 */
static void handle_timeouts(struct event_base* base, struct timeval* now,
struct timeval* wait)
{
struct event* p;
#ifndef S_SPLINT_S
wait->tv_sec = (time_t)-1;
#endif
while((rbnode_type*)(p = (struct event*)rbtree_first(base->times))
!=RBTREE_NULL) {
#ifndef S_SPLINT_S
if(p->ev_timeout.tv_sec > now->tv_sec ||
(p->ev_timeout.tv_sec==now->tv_sec &&
p->ev_timeout.tv_usec > now->tv_usec)) {
/* there is a next larger timeout. wait for it */
wait->tv_sec = p->ev_timeout.tv_sec - now->tv_sec;
if(now->tv_usec > p->ev_timeout.tv_usec) {
wait->tv_sec--;
wait->tv_usec = 1000000 - (now->tv_usec -
p->ev_timeout.tv_usec);
} else {
wait->tv_usec = p->ev_timeout.tv_usec
- now->tv_usec;
}
return;
}
#endif
/* event times out, remove it */
(void)rbtree_delete(base->times, p);
p->ev_events &= ~EV_TIMEOUT;
fptr_ok(fptr_whitelist_event(p->ev_callback));
(*p->ev_callback)(p->ev_fd, EV_TIMEOUT, p->ev_arg);
}
}
/** call select and callbacks for that */
static int handle_select(struct event_base* base, struct timeval* wait)
{
fd_set r, w;
int ret, i;
#ifndef S_SPLINT_S
if(wait->tv_sec==(time_t)-1)
wait = NULL;
#endif
memmove(&r, &base->reads, sizeof(fd_set));
memmove(&w, &base->writes, sizeof(fd_set));
memmove(&base->ready, &base->content, sizeof(fd_set));
if((ret = select(base->maxfd+1, &r, &w, NULL, wait)) == -1) {
ret = errno;
if(settime(base) < 0)
return -1;
errno = ret;
if(ret == EAGAIN || ret == EINTR)
return 0;
return -1;
}
if(settime(base) < 0)
return -1;
for(i=0; i<base->maxfd+1; i++) {
short bits = 0;
if(!base->fds[i] || !(FD_ISSET(i, &base->ready))) {
continue;
}
if(FD_ISSET(i, &r)) {
bits |= EV_READ;
ret--;
}
if(FD_ISSET(i, &w)) {
bits |= EV_WRITE;
ret--;
}
bits &= base->fds[i]->ev_events;
if(bits) {
fptr_ok(fptr_whitelist_event(
base->fds[i]->ev_callback));
(*base->fds[i]->ev_callback)(base->fds[i]->ev_fd,
bits, base->fds[i]->ev_arg);
if(ret==0)
break;
}
}
return 0;
}
/** run select in a loop */
int event_base_dispatch(struct event_base* base)
{
struct timeval wait;
if(settime(base) < 0)
return -1;
while(!base->need_to_exit)
{
/* see if timeouts need handling */
handle_timeouts(base, base->time_tv, &wait);
if(base->need_to_exit)
return 0;
/* do select */
if(handle_select(base, &wait) < 0) {
if(base->need_to_exit)
return 0;
return -1;
}
}
return 0;
}
/** exit that loop */
int event_base_loopexit(struct event_base* base,
struct timeval* ATTR_UNUSED(tv))
{
base->need_to_exit = 1;
return 0;
}
/* free event base, free events yourself */
void event_base_free(struct event_base* base)
{
if(!base)
return;
free(base->times);
free(base->fds);
free(base->signals);
free(base);
}
/** set content of event */
void event_set(struct event* ev, int fd, short bits,
void (*cb)(int, short, void *), void* arg)
{
ev->node.key = ev;
ev->ev_fd = fd;
ev->ev_events = bits;
ev->ev_callback = cb;
fptr_ok(fptr_whitelist_event(ev->ev_callback));
ev->ev_arg = arg;
ev->added = 0;
}
/* add event to a base */
int event_base_set(struct event_base* base, struct event* ev)
{
ev->ev_base = base;
ev->added = 0;
return 0;
}
/* add event to make it active, you may not change it with event_set anymore */
int event_add(struct event* ev, struct timeval* tv)
{
if(ev->added)
event_del(ev);
if(ev->ev_fd != -1 && ev->ev_fd >= ev->ev_base->capfd)
return -1;
if( (ev->ev_events&(EV_READ|EV_WRITE)) && ev->ev_fd != -1) {
ev->ev_base->fds[ev->ev_fd] = ev;
if(ev->ev_events&EV_READ) {
FD_SET(FD_SET_T ev->ev_fd, &ev->ev_base->reads);
}
if(ev->ev_events&EV_WRITE) {
FD_SET(FD_SET_T ev->ev_fd, &ev->ev_base->writes);
}
FD_SET(FD_SET_T ev->ev_fd, &ev->ev_base->content);
FD_CLR(FD_SET_T ev->ev_fd, &ev->ev_base->ready);
if(ev->ev_fd > ev->ev_base->maxfd)
ev->ev_base->maxfd = ev->ev_fd;
}
if(tv && (ev->ev_events&EV_TIMEOUT)) {
#ifndef S_SPLINT_S
struct timeval *now = ev->ev_base->time_tv;
ev->ev_timeout.tv_sec = tv->tv_sec + now->tv_sec;
ev->ev_timeout.tv_usec = tv->tv_usec + now->tv_usec;
while(ev->ev_timeout.tv_usec > 1000000) {
ev->ev_timeout.tv_usec -= 1000000;
ev->ev_timeout.tv_sec++;
}
#endif
(void)rbtree_insert(ev->ev_base->times, &ev->node);
}
ev->added = 1;
return 0;
}
/* remove event, you may change it again */
int event_del(struct event* ev)
{
if(ev->ev_fd != -1 && ev->ev_fd >= ev->ev_base->capfd)
return -1;
if((ev->ev_events&EV_TIMEOUT))
(void)rbtree_delete(ev->ev_base->times, &ev->node);
if((ev->ev_events&(EV_READ|EV_WRITE)) && ev->ev_fd != -1) {
ev->ev_base->fds[ev->ev_fd] = NULL;
FD_CLR(FD_SET_T ev->ev_fd, &ev->ev_base->reads);
FD_CLR(FD_SET_T ev->ev_fd, &ev->ev_base->writes);
FD_CLR(FD_SET_T ev->ev_fd, &ev->ev_base->ready);
FD_CLR(FD_SET_T ev->ev_fd, &ev->ev_base->content);
}
ev->added = 0;
return 0;
}
/** which base gets to handle signals */
static struct event_base* signal_base = NULL;
/** signal handler */
static RETSIGTYPE sigh(int sig)
{
struct event* ev;
if(!signal_base || sig < 0 || sig >= MAX_SIG)
return;
ev = signal_base->signals[sig];
if(!ev)
return;
fptr_ok(fptr_whitelist_event(ev->ev_callback));
(*ev->ev_callback)(sig, EV_SIGNAL, ev->ev_arg);
}
/** install signal handler */
int signal_add(struct event* ev, struct timeval* ATTR_UNUSED(tv))
{
if(ev->ev_fd == -1 || ev->ev_fd >= MAX_SIG)
return -1;
signal_base = ev->ev_base;
ev->ev_base->signals[ev->ev_fd] = ev;
ev->added = 1;
if(signal(ev->ev_fd, sigh) == SIG_ERR) {
return -1;
}
return 0;
}
/** remove signal handler */
int signal_del(struct event* ev)
{
if(ev->ev_fd == -1 || ev->ev_fd >= MAX_SIG)
return -1;
ev->ev_base->signals[ev->ev_fd] = NULL;
ev->added = 0;
return 0;
}
#else /* USE_MINI_EVENT */
#ifndef USE_WINSOCK
int mini_ev_cmp(const void* ATTR_UNUSED(a), const void* ATTR_UNUSED(b))
{
return 0;
}
#endif /* not USE_WINSOCK */
#endif /* USE_MINI_EVENT */