diff options
Diffstat (limited to 'lib/util/event_poll.c')
| -rw-r--r-- | lib/util/event_poll.c | 211 |
1 files changed, 211 insertions, 0 deletions
diff --git a/lib/util/event_poll.c b/lib/util/event_poll.c new file mode 100644 index 0000000..22cda24 --- /dev/null +++ b/lib/util/event_poll.c @@ -0,0 +1,211 @@ +/* + * Copyright (c) 2013-2015 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 <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 <time.h> +#include <unistd.h> +#include <errno.h> +#include <poll.h> + +#include "sudo_compat.h" +#include "sudo_util.h" +#include "sudo_fatal.h" +#include "sudo_debug.h" +#include "sudo_event.h" + +int +sudo_ev_base_alloc_impl(struct sudo_event_base *base) +{ + int i; + debug_decl(sudo_ev_base_alloc_impl, SUDO_DEBUG_EVENT) + + base->pfd_high = -1; + base->pfd_max = 32; + base->pfds = reallocarray(NULL, base->pfd_max, sizeof(struct pollfd)); + if (base->pfds == NULL) { + sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO, + "%s: unable to allocate %d pollfds", __func__, base->pfd_max); + base->pfd_max = 0; + debug_return_int(-1); + } + for (i = 0; i < base->pfd_max; i++) { + base->pfds[i].fd = -1; + } + + debug_return_int(0); +} + +void +sudo_ev_base_free_impl(struct sudo_event_base *base) +{ + debug_decl(sudo_ev_base_free_impl, SUDO_DEBUG_EVENT) + free(base->pfds); + debug_return; +} + +int +sudo_ev_add_impl(struct sudo_event_base *base, struct sudo_event *ev) +{ + struct pollfd *pfd; + debug_decl(sudo_ev_add_impl, SUDO_DEBUG_EVENT) + + /* If out of space in pfds array, realloc. */ + if (base->pfd_free == base->pfd_max) { + struct pollfd *pfds; + int i; + + pfds = + reallocarray(base->pfds, base->pfd_max, 2 * sizeof(struct pollfd)); + if (pfds == NULL) { + sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO, + "%s: unable to allocate %d pollfds", __func__, base->pfd_max * 2); + debug_return_int(-1); + } + base->pfds = pfds; + base->pfd_max *= 2; + for (i = base->pfd_free; i < base->pfd_max; i++) { + base->pfds[i].fd = -1; + } + } + + /* Fill in pfd entry. */ + ev->pfd_idx = base->pfd_free; + pfd = &base->pfds[ev->pfd_idx]; + pfd->fd = ev->fd; + pfd->events = 0; + if (ISSET(ev->events, SUDO_EV_READ)) + pfd->events |= POLLIN; + if (ISSET(ev->events, SUDO_EV_WRITE)) + pfd->events |= POLLOUT; + + /* Update pfd_high and pfd_free. */ + if (ev->pfd_idx > base->pfd_high) + base->pfd_high = ev->pfd_idx; + for (;;) { + if (++base->pfd_free == base->pfd_max) + break; + if (base->pfds[base->pfd_free].fd == -1) + break; + } + + debug_return_int(0); +} + +int +sudo_ev_del_impl(struct sudo_event_base *base, struct sudo_event *ev) +{ + debug_decl(sudo_ev_del_impl, SUDO_DEBUG_EVENT) + + /* Mark pfd entry unused, add to free list and adjust high slot. */ + base->pfds[ev->pfd_idx].fd = -1; + if (ev->pfd_idx < base->pfd_free) + base->pfd_free = ev->pfd_idx; + while (base->pfd_high >= 0 && base->pfds[base->pfd_high].fd == -1) + base->pfd_high--; + + debug_return_int(0); +} + +#ifdef HAVE_PPOLL +static int +sudo_ev_poll(struct pollfd *fds, nfds_t nfds, const struct timespec *timo) +{ + return ppoll(fds, nfds, timo, NULL); +} +#else +static int +sudo_ev_poll(struct pollfd *fds, nfds_t nfds, const struct timespec *timo) +{ + const int timeout = + timo ? (timo->tv_sec * 1000) + (timo->tv_nsec / 1000000) : -1; + + return poll(fds, nfds, timeout); +} +#endif /* HAVE_PPOLL */ + +int +sudo_ev_scan_impl(struct sudo_event_base *base, int flags) +{ + struct timespec now, ts, *timeout; + struct sudo_event *ev; + int nready; + debug_decl(sudo_ev_scan_impl, SUDO_DEBUG_EVENT) + + if ((ev = TAILQ_FIRST(&base->timeouts)) != NULL) { + sudo_gettime_mono(&now); + sudo_timespecsub(&ev->timeout, &now, &ts); + if (ts.tv_sec < 0) + sudo_timespecclear(&ts); + timeout = &ts; + } else { + if (ISSET(flags, SUDO_EVLOOP_NONBLOCK)) { + sudo_timespecclear(&ts); + timeout = &ts; + } else { + timeout = NULL; + } + } + + nready = sudo_ev_poll(base->pfds, base->pfd_high + 1, timeout); + sudo_debug_printf(SUDO_DEBUG_INFO, "%s: %d fds ready", __func__, nready); + switch (nready) { + case -1: + /* Error or interrupted by signal. */ + debug_return_int(-1); + case 0: + /* Front end will activate timeout events. */ + break; + default: + /* Activate each I/O event that fired. */ + TAILQ_FOREACH(ev, &base->events, entries) { + if (ev->pfd_idx != -1 && base->pfds[ev->pfd_idx].revents) { + int what = 0; + if (base->pfds[ev->pfd_idx].revents & (POLLIN|POLLHUP|POLLNVAL|POLLERR)) + what |= (ev->events & SUDO_EV_READ); + if (base->pfds[ev->pfd_idx].revents & (POLLOUT|POLLHUP|POLLNVAL|POLLERR)) + what |= (ev->events & SUDO_EV_WRITE); + /* Make event active. */ + sudo_debug_printf(SUDO_DEBUG_DEBUG, + "%s: polled fd %d, events %d, activating %p", + __func__, ev->fd, what, ev); + ev->revents = what; + sudo_ev_activate(base, ev); + } + } + break; + } + debug_return_int(nready); +} |