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|
/*
* Copyright (c) 2013-2018 Todd C. Miller <Todd.Miller@sudo.ws>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
/*
* This is an open source non-commercial project. Dear PVS-Studio, please check it.
* PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com
*/
#include <config.h>
#include <sys/types.h>
#include <sys/time.h>
#include <stdio.h>
#include <stdlib.h>
#ifdef HAVE_STDBOOL_H
# include <stdbool.h>
#else
# include "compat/stdbool.h"
#endif /* HAVE_STDBOOL_H */
#ifdef HAVE_STRING_H
# include <string.h>
#endif /* HAVE_STRING_H */
#ifdef HAVE_STRINGS_H
# include <strings.h>
#endif /* HAVE_STRINGS_H */
#include <errno.h>
#include <fcntl.h>
#include <time.h>
#include <unistd.h>
#include "sudo_compat.h"
#include "sudo_fatal.h"
#include "sudo_debug.h"
#include "sudo_event.h"
#include "sudo_util.h"
static void sudo_ev_init(struct sudo_event *ev, int fd, short events,
sudo_ev_callback_t callback, void *closure);
/* Default event base when none is specified. */
static struct sudo_event_base *default_base;
/* We need the event base to be available from the signal handler. */
static struct sudo_event_base *signal_base;
/*
* Add an event to the base's active queue and mark it active.
* This is extern so sudo_ev_scan_impl() can call it.
*/
void
sudo_ev_activate(struct sudo_event_base *base, struct sudo_event *ev)
{
TAILQ_INSERT_TAIL(&base->active, ev, active_entries);
SET(ev->flags, SUDO_EVQ_ACTIVE);
}
/*
* Remove an event from the base's active queue and mark it inactive.
*/
static inline void
sudo_ev_deactivate(struct sudo_event_base *base, struct sudo_event *ev)
{
CLR(ev->flags, SUDO_EVQ_ACTIVE);
TAILQ_REMOVE(&base->active, ev, active_entries);
}
/*
* Clear out the base's active queue and mark all events as inactive.
*/
static void
sudo_ev_deactivate_all(struct sudo_event_base *base)
{
struct sudo_event *ev;
debug_decl(sudo_ev_deactivate_all, SUDO_DEBUG_EVENT)
while ((ev = TAILQ_FIRST(&base->active)) != NULL)
sudo_ev_deactivate(base, ev);
debug_return;
}
/*
* Activate all signal events for which the corresponding signal_pending[]
* flag is set.
*/
static void
sudo_ev_activate_sigevents(struct sudo_event_base *base)
{
struct sudo_event *ev;
sigset_t set, oset;
int i;
debug_decl(sudo_ev_activate_sigevents, SUDO_DEBUG_EVENT)
/*
* We treat this as a critical section since the signal handler
* could modify the siginfo[] entry.
*/
sigfillset(&set);
sigprocmask(SIG_BLOCK, &set, &oset);
base->signal_caught = 0;
for (i = 0; i < NSIG; i++) {
if (!base->signal_pending[i])
continue;
base->signal_pending[i] = 0;
TAILQ_FOREACH(ev, &base->signals[i], entries) {
if (ISSET(ev->events, SUDO_EV_SIGINFO)) {
struct sudo_ev_siginfo_container *sc = ev->closure;
if (base->siginfo[i]->si_signo == 0) {
/* No siginfo available. */
sc->siginfo = NULL;
} else {
sc->siginfo = (siginfo_t *)sc->si_buf;
memcpy(sc->siginfo, base->siginfo[i], sizeof(siginfo_t));
}
}
/* Make event active. */
ev->revents = ev->events & (SUDO_EV_SIGNAL|SUDO_EV_SIGINFO);
TAILQ_INSERT_TAIL(&base->active, ev, active_entries);
SET(ev->flags, SUDO_EVQ_ACTIVE);
}
}
sigprocmask(SIG_SETMASK, &oset, NULL);
debug_return;
}
/*
* Internal callback for SUDO_EV_SIGNAL and SUDO_EV_SIGINFO.
*/
static void
signal_pipe_cb(int fd, int what, void *v)
{
struct sudo_event_base *base = v;
unsigned char ch;
ssize_t nread;
debug_decl(signal_pipe_cb, SUDO_DEBUG_EVENT)
/*
* Drain signal_pipe, the signal handler updated base->signals_pending.
* Actual processing of signal events is done when poll/select is
* interrupted by a signal.
*/
while ((nread = read(fd, &ch, 1)) > 0) {
sudo_debug_printf(SUDO_DEBUG_INFO,
"%s: received signal %d", __func__, (int)ch);
}
if (nread == -1 && errno != EAGAIN) {
sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO|SUDO_DEBUG_ERRNO,
"%s: error reading from signal pipe fd %d", __func__, fd);
}
/* Activate signal events. */
sudo_ev_activate_sigevents(base);
debug_return;
}
static int
sudo_ev_base_init(struct sudo_event_base *base)
{
int i;
debug_decl(sudo_ev_base_init, SUDO_DEBUG_EVENT)
TAILQ_INIT(&base->events);
TAILQ_INIT(&base->timeouts);
for (i = 0; i < NSIG; i++)
TAILQ_INIT(&base->signals[i]);
if (sudo_ev_base_alloc_impl(base) != 0) {
sudo_debug_printf(SUDO_DEBUG_ERROR,
"%s: unable to allocate impl base", __func__);
goto bad;
}
if (pipe2(base->signal_pipe, O_NONBLOCK|O_CLOEXEC) != 0) {
sudo_debug_printf(SUDO_DEBUG_ERROR,
"%s: unable to create signal pipe", __func__);
goto bad;
}
sudo_ev_init(&base->signal_event, base->signal_pipe[0],
SUDO_EV_READ|SUDO_EV_PERSIST, signal_pipe_cb, base);
debug_return_int(0);
bad:
/* Note: signal_pipe[] not filled in. */
sudo_ev_base_free_impl(base);
debug_return_int(-1);
}
struct sudo_event_base *
sudo_ev_base_alloc_v1(void)
{
struct sudo_event_base *base;
debug_decl(sudo_ev_base_alloc, SUDO_DEBUG_EVENT)
base = calloc(1, sizeof(*base));
if (base == NULL) {
sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO,
"%s: unable to allocate base", __func__);
debug_return_ptr(NULL);
}
if (sudo_ev_base_init(base) != 0) {
free(base);
debug_return_ptr(NULL);
}
debug_return_ptr(base);
}
void
sudo_ev_base_free_v1(struct sudo_event_base *base)
{
struct sudo_event *ev, *next;
int i;
debug_decl(sudo_ev_base_free, SUDO_DEBUG_EVENT)
if (base == NULL)
debug_return;
/* Reset the default base if necessary. */
if (default_base == base)
default_base = NULL;
/* Remove any existing events before freeing the base. */
TAILQ_FOREACH_SAFE(ev, &base->events, entries, next) {
sudo_ev_del(base, ev);
}
for (i = 0; i < NSIG; i++) {
TAILQ_FOREACH_SAFE(ev, &base->signals[i], entries, next) {
sudo_ev_del(base, ev);
}
free(base->siginfo[i]);
free(base->orig_handlers[i]);
}
sudo_ev_base_free_impl(base);
close(base->signal_pipe[0]);
close(base->signal_pipe[1]);
free(base);
debug_return;
}
void
sudo_ev_base_setdef_v1(struct sudo_event_base *base)
{
debug_decl(sudo_ev_base_setdef, SUDO_DEBUG_EVENT)
default_base = base;
debug_return;
}
/*
* Clear and fill in a struct sudo_event.
*/
static void
sudo_ev_init(struct sudo_event *ev, int fd, short events,
sudo_ev_callback_t callback, void *closure)
{
debug_decl(sudo_ev_init, SUDO_DEBUG_EVENT)
/* XXX - sanity check events value */
memset(ev, 0, sizeof(*ev));
ev->fd = fd;
ev->events = events;
ev->pfd_idx = -1;
ev->callback = callback;
ev->closure = closure;
debug_return;
}
struct sudo_event *
sudo_ev_alloc_v1(int fd, short events, sudo_ev_callback_t callback, void *closure)
{
struct sudo_event *ev;
debug_decl(sudo_ev_alloc, SUDO_DEBUG_EVENT)
ev = malloc(sizeof(*ev));
if (ev == NULL) {
sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO,
"%s: unable to allocate event", __func__);
debug_return_ptr(NULL);
}
/* For SUDO_EV_SIGINFO we use a container to store closure + siginfo_t */
if (ISSET(events, SUDO_EV_SIGINFO)) {
struct sudo_ev_siginfo_container *container =
malloc(sizeof(*container) + sizeof(siginfo_t) - 1);
if (container == NULL) {
sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO,
"%s: unable to allocate siginfo container", __func__);
free(ev);
debug_return_ptr(NULL);
}
container->closure = closure;
closure = container;
}
sudo_ev_init(ev, fd, events, callback, closure);
debug_return_ptr(ev);
}
void
sudo_ev_free_v1(struct sudo_event *ev)
{
debug_decl(sudo_ev_free, SUDO_DEBUG_EVENT)
if (ev == NULL)
debug_return;
/* Make sure ev is not in use before freeing it. */
if (ISSET(ev->flags, SUDO_EVQ_INSERTED))
(void)sudo_ev_del(NULL, ev);
if (ISSET(ev->events, SUDO_EV_SIGINFO))
free(ev->closure);
free(ev);
debug_return;
}
static void
sudo_ev_handler(int signo, siginfo_t *info, void *context)
{
unsigned char ch = (unsigned char)signo;
if (signal_base != NULL) {
/*
* Update signals_pending[] and siginfo[].
* All signals must be blocked any time siginfo[] is accessed.
* If no siginfo available, zero out the struct in base.
*/
if (info == NULL)
memset(signal_base->siginfo[signo], 0, sizeof(*info));
else
memcpy(signal_base->siginfo[signo], info, sizeof(*info));
signal_base->signal_pending[signo] = 1;
signal_base->signal_caught = 1;
/* Wake up the other end of the pipe. */
ignore_result(write(signal_base->signal_pipe[1], &ch, 1));
}
}
static int
sudo_ev_add_signal(struct sudo_event_base *base, struct sudo_event *ev,
bool tohead)
{
const int signo = ev->fd;
debug_decl(sudo_ev_add_signal, SUDO_DEBUG_EVENT)
sudo_debug_printf(SUDO_DEBUG_INFO,
"%s: adding event %p to base %p, signal %d, events %d",
__func__, ev, base, signo, ev->events);
if (signo >= NSIG) {
sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO,
"%s: signo %d larger than max %d", __func__, signo, NSIG - 1);
debug_return_int(-1);
}
if ((ev->events & ~(SUDO_EV_SIGNAL|SUDO_EV_SIGINFO|SUDO_EV_PERSIST)) != 0) {
sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO,
"%s: invalid event set 0x%x", __func__, ev->events);
debug_return_int(-1);
}
/*
* Allocate base->siginfo[signo] and base->orig_handlers[signo] as needed.
*/
if (base->siginfo[signo] == NULL) {
base->siginfo[signo] = malloc(sizeof(*base->siginfo[signo]));
if (base->siginfo[signo] == NULL) {
sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO,
"%s: unable to allocate siginfo for signo %d",
__func__, signo);
debug_return_int(-1);
}
}
if (base->orig_handlers[signo] == NULL) {
base->orig_handlers[signo] =
malloc(sizeof(*base->orig_handlers[signo]));
if (base->orig_handlers[signo] == NULL) {
sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO,
"%s: unable to allocate orig_handlers for signo %d",
__func__, signo);
debug_return_int(-1);
}
}
/* Install signal handler as needed, saving the original value. */
if (TAILQ_EMPTY(&base->signals[signo])) {
struct sigaction sa;
memset(&sa, 0, sizeof(sa));
sigfillset(&sa.sa_mask);
sa.sa_flags = SA_RESTART|SA_SIGINFO;
sa.sa_sigaction = sudo_ev_handler;
if (sigaction(signo, &sa, base->orig_handlers[signo]) != 0) {
sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO,
"%s: unable to install handler for signo %d", __func__, signo);
debug_return_int(-1);
}
base->num_handlers++;
}
/*
* Insert signal event into the proper tail queue.
* Signal events are always persistent.
*/
ev->base = base;
if (tohead) {
TAILQ_INSERT_HEAD(&base->signals[signo], ev, entries);
} else {
TAILQ_INSERT_TAIL(&base->signals[signo], ev, entries);
}
SET(ev->events, SUDO_EV_PERSIST);
SET(ev->flags, SUDO_EVQ_INSERTED);
/* Add the internal signal_pipe event on demand. */
if (!ISSET(base->signal_event.flags, SUDO_EVQ_INSERTED))
sudo_ev_add(base, &base->signal_event, NULL, true);
/* Update global signal base so handler to update signals_pending[] */
signal_base = base;
debug_return_int(0);
}
int
sudo_ev_add_v1(struct sudo_event_base *base, struct sudo_event *ev,
struct timeval *timo, bool tohead)
{
struct timespec tsbuf, *ts = NULL;
if (timo != NULL) {
TIMEVAL_TO_TIMESPEC(timo, &tsbuf);
ts = &tsbuf;
}
return sudo_ev_add_v2(base, ev, ts, tohead);
}
int
sudo_ev_add_v2(struct sudo_event_base *base, struct sudo_event *ev,
struct timespec *timo, bool tohead)
{
debug_decl(sudo_ev_add, SUDO_DEBUG_EVENT)
/* If no base specified, use existing or default base. */
if (base == NULL) {
if (ev->base != NULL) {
base = ev->base;
} else if (default_base != NULL) {
base = default_base;
} else {
sudo_debug_printf(SUDO_DEBUG_ERROR, "%s: no base specified",
__func__);
debug_return_int(-1);
}
}
/* Only add new events to the events list. */
if (ISSET(ev->flags, SUDO_EVQ_INSERTED)) {
/* If event no longer has a timeout, remove from timeouts queue. */
if (timo == NULL && ISSET(ev->flags, SUDO_EVQ_TIMEOUTS)) {
sudo_debug_printf(SUDO_DEBUG_INFO,
"%s: removing event %p from timeouts queue", __func__, ev);
CLR(ev->flags, SUDO_EVQ_TIMEOUTS);
TAILQ_REMOVE(&base->timeouts, ev, timeouts_entries);
}
} else {
/* Special handling for signal events. */
if (ev->events & (SUDO_EV_SIGNAL|SUDO_EV_SIGINFO))
debug_return_int(sudo_ev_add_signal(base, ev, tohead));
/* Add event to the base. */
sudo_debug_printf(SUDO_DEBUG_INFO,
"%s: adding event %p to base %p, fd %d, events %d",
__func__, ev, base, ev->fd, ev->events);
if (ev->events & (SUDO_EV_READ|SUDO_EV_WRITE)) {
if (sudo_ev_add_impl(base, ev) != 0)
debug_return_int(-1);
}
ev->base = base;
if (tohead) {
TAILQ_INSERT_HEAD(&base->events, ev, entries);
} else {
TAILQ_INSERT_TAIL(&base->events, ev, entries);
}
SET(ev->flags, SUDO_EVQ_INSERTED);
}
/* Timeouts can be changed for existing events. */
if (timo != NULL) {
struct sudo_event *evtmp;
if (ISSET(ev->flags, SUDO_EVQ_TIMEOUTS)) {
/* Remove from timeouts list, then add back. */
TAILQ_REMOVE(&base->timeouts, ev, timeouts_entries);
}
/* Convert to absolute time and insert in sorted order; O(n). */
sudo_gettime_mono(&ev->timeout);
sudo_timespecadd(&ev->timeout, timo, &ev->timeout);
TAILQ_FOREACH(evtmp, &base->timeouts, timeouts_entries) {
if (sudo_timespeccmp(timo, &evtmp->timeout, <))
break;
}
if (evtmp != NULL) {
TAILQ_INSERT_BEFORE(evtmp, ev, timeouts_entries);
} else {
TAILQ_INSERT_TAIL(&base->timeouts, ev, timeouts_entries);
}
SET(ev->flags, SUDO_EVQ_TIMEOUTS);
}
debug_return_int(0);
}
/*
* Remove an event from the base, if specified, or the base embedded
* in the event if not. Note that there are multiple tail queues.
*/
int
sudo_ev_del_v1(struct sudo_event_base *base, struct sudo_event *ev)
{
debug_decl(sudo_ev_del, SUDO_DEBUG_EVENT)
/* Make sure event is really in the queue. */
if (!ISSET(ev->flags, SUDO_EVQ_INSERTED)) {
sudo_debug_printf(SUDO_DEBUG_INFO, "%s: event %p not in queue",
__func__, ev);
debug_return_int(0);
}
/* Check for event base mismatch, if one is specified. */
if (base == NULL) {
if (ev->base == NULL) {
sudo_debug_printf(SUDO_DEBUG_ERROR, "%s: no base specified",
__func__);
debug_return_int(-1);
}
base = ev->base;
} else if (base != ev->base) {
sudo_debug_printf(SUDO_DEBUG_ERROR, "%s: mismatch base %p, ev->base %p",
__func__, base, ev->base);
debug_return_int(-1);
}
if (ev->events & (SUDO_EV_SIGNAL|SUDO_EV_SIGINFO)) {
const int signo = ev->fd;
sudo_debug_printf(SUDO_DEBUG_INFO,
"%s: removing event %p from base %p, signo %d, events %d",
__func__, ev, base, signo, ev->events);
/* Unlink from signal event list. */
TAILQ_REMOVE(&base->signals[signo], ev, entries);
if (TAILQ_EMPTY(&base->signals[signo])) {
if (sigaction(signo, base->orig_handlers[signo], NULL) != 0) {
sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO,
"%s: unable to restore handler for signo %d",
__func__, signo);
debug_return_int(-1);
}
base->num_handlers--;
}
if (base->num_handlers == 0) {
/* No registered signal events, remove internal event. */
sudo_ev_del(base, &base->signal_event);
}
} else {
sudo_debug_printf(SUDO_DEBUG_INFO,
"%s: removing event %p from base %p, fd %d, events %d",
__func__, ev, base, ev->fd, ev->events);
/* Call backend. */
if (ev->events & (SUDO_EV_READ|SUDO_EV_WRITE)) {
if (sudo_ev_del_impl(base, ev) != 0)
debug_return_int(-1);
}
/* Unlink from event list. */
TAILQ_REMOVE(&base->events, ev, entries);
/* Unlink from timeouts list. */
if (ISSET(ev->flags, SUDO_EVQ_TIMEOUTS))
TAILQ_REMOVE(&base->timeouts, ev, timeouts_entries);
}
/* Unlink from active list. */
if (ISSET(ev->flags, SUDO_EVQ_ACTIVE))
TAILQ_REMOVE(&base->active, ev, active_entries);
/* Mark event unused. */
ev->flags = 0;
ev->pfd_idx = -1;
debug_return_int(0);
}
int
sudo_ev_dispatch_v1(struct sudo_event_base *base)
{
return sudo_ev_loop_v1(base, 0);
}
/*
* Run main event loop.
* Returns 0 on success, 1 if no events registered and -1 on error
*/
int
sudo_ev_loop_v1(struct sudo_event_base *base, int flags)
{
struct timespec now;
struct sudo_event *ev;
int nready, rc = 0;
debug_decl(sudo_ev_loop, SUDO_DEBUG_EVENT)
/*
* If sudo_ev_loopexit() was called when events were not running
* the next invocation of sudo_ev_loop() only runs once.
* All other base flags are ignored unless we are running events.
* Note that SUDO_EVLOOP_ONCE and SUDO_EVBASE_LOOPONCE are equivalent.
*/
base->flags |= (flags & SUDO_EVLOOP_ONCE);
base->flags &= (SUDO_EVBASE_LOOPEXIT|SUDO_EVBASE_LOOPONCE);
for (;;) {
rescan:
/* Make sure we have some events. */
if (TAILQ_EMPTY(&base->events)) {
rc = 1;
break;
}
/* Call backend to scan for I/O events. */
TAILQ_INIT(&base->active);
nready = sudo_ev_scan_impl(base, flags);
switch (nready) {
case -1:
if (errno == ENOMEM)
continue;
if (errno == EINTR) {
/* Interrupted by signal, check for sigevents. */
if (base->signal_caught) {
signal_pipe_cb(base->signal_pipe[0], SUDO_EV_READ, base);
break;
}
continue;
}
rc = -1;
goto done;
case 0:
/* Timed out, activate timeout events. */
sudo_gettime_mono(&now);
while ((ev = TAILQ_FIRST(&base->timeouts)) != NULL) {
if (sudo_timespeccmp(&ev->timeout, &now, >))
break;
/* Remove from timeouts list. */
CLR(ev->flags, SUDO_EVQ_TIMEOUTS);
TAILQ_REMOVE(&base->timeouts, ev, timeouts_entries);
/* Make event active. */
ev->revents = SUDO_EV_TIMEOUT;
TAILQ_INSERT_TAIL(&base->active, ev, active_entries);
SET(ev->flags, SUDO_EVQ_ACTIVE);
}
if (ISSET(flags, SUDO_EVLOOP_NONBLOCK)) {
/* If nonblocking, return immediately if no active events. */
if (TAILQ_EMPTY(&base->active))
goto done;
}
break;
default:
/* I/O events active, sudo_ev_scan_impl() already added them. */
break;
}
/*
* Service each event in the active queue.
* We store the current event pointer in the base so that
* it can be cleared by sudo_ev_del(). This prevents a use
* after free if the callback frees its own event.
*/
while ((ev = TAILQ_FIRST(&base->active)) != NULL) {
/* Pop first event off the active queue. */
sudo_ev_deactivate(base, ev);
/* Remove from base unless persistent. */
if (!ISSET(ev->events, SUDO_EV_PERSIST))
sudo_ev_del(base, ev);
ev->callback(ev->fd, ev->revents,
ev->closure == sudo_ev_self_cbarg() ? ev : ev->closure);
if (ISSET(base->flags, SUDO_EVBASE_LOOPBREAK)) {
/* Stop processing events immediately. */
SET(base->flags, SUDO_EVBASE_GOT_BREAK);
sudo_ev_deactivate_all(base);
goto done;
}
if (ISSET(base->flags, SUDO_EVBASE_LOOPCONT)) {
/* Rescan events and start polling again. */
CLR(base->flags, SUDO_EVBASE_LOOPCONT);
sudo_ev_deactivate_all(base);
goto rescan;
}
}
if (ISSET(base->flags, SUDO_EVBASE_LOOPONCE)) {
/* SUDO_EVBASE_LOOPEXIT is always set w/ SUDO_EVBASE_LOOPONCE */
if (ISSET(base->flags, SUDO_EVBASE_LOOPEXIT))
SET(base->flags, SUDO_EVBASE_GOT_EXIT);
sudo_ev_deactivate_all(base);
break;
}
}
done:
base->flags &= SUDO_EVBASE_GOT_MASK;
debug_return_int(rc);
}
void
sudo_ev_loopexit_v1(struct sudo_event_base *base)
{
debug_decl(sudo_ev_loopexit, SUDO_DEBUG_EVENT)
/* SUDO_EVBASE_LOOPBREAK trumps SUDO_EVBASE_LOOPEXIT */
if (!ISSET(base->flags, SUDO_EVBASE_LOOPBREAK)) {
/* SUDO_EVBASE_LOOPEXIT trumps SUDO_EVBASE_LOOPCONT */
CLR(base->flags, SUDO_EVBASE_LOOPCONT);
SET(base->flags, (SUDO_EVBASE_LOOPEXIT|SUDO_EVBASE_LOOPONCE));
}
debug_return;
}
void
sudo_ev_loopbreak_v1(struct sudo_event_base *base)
{
debug_decl(sudo_ev_loopbreak, SUDO_DEBUG_EVENT)
/* SUDO_EVBASE_LOOPBREAK trumps SUDO_EVBASE_LOOP{CONT,EXIT,ONCE}. */
CLR(base->flags, (SUDO_EVBASE_LOOPCONT|SUDO_EVBASE_LOOPEXIT|SUDO_EVBASE_LOOPONCE));
SET(base->flags, SUDO_EVBASE_LOOPBREAK);
debug_return;
}
void
sudo_ev_loopcontinue_v1(struct sudo_event_base *base)
{
debug_decl(sudo_ev_loopcontinue, SUDO_DEBUG_EVENT)
/* SUDO_EVBASE_LOOP{BREAK,EXIT} trumps SUDO_EVBASE_LOOPCONT */
if (!ISSET(base->flags, SUDO_EVBASE_LOOPONCE|SUDO_EVBASE_LOOPBREAK)) {
SET(base->flags, SUDO_EVBASE_LOOPCONT);
}
debug_return;
}
bool
sudo_ev_got_exit_v1(struct sudo_event_base *base)
{
debug_decl(sudo_ev_got_exit, SUDO_DEBUG_EVENT)
debug_return_bool(ISSET(base->flags, SUDO_EVBASE_GOT_EXIT));
}
bool
sudo_ev_got_break_v1(struct sudo_event_base *base)
{
debug_decl(sudo_ev_got_break, SUDO_DEBUG_EVENT)
debug_return_bool(ISSET(base->flags, SUDO_EVBASE_GOT_BREAK));
}
int
sudo_ev_get_timeleft_v1(struct sudo_event *ev, struct timeval *tv)
{
struct timespec ts;
int ret;
ret = sudo_ev_get_timeleft_v2(ev, &ts);
TIMESPEC_TO_TIMEVAL(tv, &ts);
return ret;
}
int
sudo_ev_get_timeleft_v2(struct sudo_event *ev, struct timespec *ts)
{
struct timespec now;
debug_decl(sudo_ev_get_timeleft, SUDO_DEBUG_EVENT)
if (!ISSET(ev->flags, SUDO_EVQ_TIMEOUTS)) {
sudo_timespecclear(ts);
debug_return_int(-1);
}
sudo_gettime_mono(&now);
sudo_timespecsub(&ev->timeout, &now, ts);
if (ts->tv_sec < 0)
sudo_timespecclear(ts);
debug_return_int(0);
}
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