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-rw-r--r--lib/util/event_poll.c236
1 files changed, 236 insertions, 0 deletions
diff --git a/lib/util/event_poll.c b/lib/util/event_poll.c
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index 0000000..245fe59
--- /dev/null
+++ b/lib/util/event_poll.c
@@ -0,0 +1,236 @@
+/*
+ * SPDX-License-Identifier: ISC
+ *
+ * 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/resource.h>
+
+#include <limits.h>
+#include <poll.h>
+#include <stdlib.h>
+#include <time.h>
+
+#include <sudo_compat.h>
+#include <sudo_util.h>
+#include <sudo_fatal.h>
+#include <sudo_debug.h>
+#include <sudo_event.h>
+
+#if defined(OPEN_MAX) && OPEN_MAX > 256
+# define SUDO_OPEN_MAX OPEN_MAX
+#else
+# define SUDO_OPEN_MAX 256
+#endif
+
+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, (size_t)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)
+{
+ static int nofile_max = -1;
+ struct pollfd *pfd;
+ debug_decl(sudo_ev_add_impl, SUDO_DEBUG_EVENT);
+
+ if (nofile_max == -1) {
+ struct rlimit rlim;
+ if (getrlimit(RLIMIT_NOFILE, &rlim) == 0) {
+ nofile_max = (int)rlim.rlim_cur;
+ } else {
+ nofile_max = SUDO_OPEN_MAX;
+ }
+ }
+
+ /* If out of space in pfds array, realloc. */
+ if (base->pfd_free == base->pfd_max) {
+ struct pollfd *pfds;
+ int i, new_max;
+
+ /* Don't allow pfd_max to go over RLIM_NOFILE */
+ new_max = base->pfd_max * 2;
+ if (new_max > nofile_max)
+ new_max = nofile_max;
+ if (base->pfd_free == new_max) {
+ sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO,
+ "%s: out of fds (max %d)", __func__, nofile_max);
+ debug_return_int(-1);
+ }
+ sudo_debug_printf(SUDO_DEBUG_INFO|SUDO_DEBUG_LINENO,
+ "%s: pfd_max %d -> %d", __func__, base->pfd_max, new_max);
+ pfds = reallocarray(base->pfds, (size_t)new_max, sizeof(struct pollfd));
+ if (pfds == NULL) {
+ sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO,
+ "%s: unable to allocate %d pollfds", __func__, new_max);
+ debug_return_int(-1);
+ }
+ base->pfds = pfds;
+ base->pfd_max = new_max;
+ for (i = base->pfd_free; i < base->pfd_max; i++) {
+ base->pfds[i].fd = -1;
+ }
+ }
+
+ /* Fill in pfd entry. */
+ sudo_debug_printf(SUDO_DEBUG_DEBUG|SUDO_DEBUG_LINENO,
+ "%s: choosing free slot %d", __func__, base->pfd_free);
+ ev->pfd_idx = (short)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;
+ sudo_debug_printf(SUDO_DEBUG_DEBUG|SUDO_DEBUG_LINENO,
+ "%s: new free slot %d", __func__, base->pfd_free);
+ }
+ 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, unsigned 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, (nfds_t)base->pfd_high + 1, timeout);
+ switch (nready) {
+ case -1:
+ /* Error: EINTR (signal) or EINVAL (nfds > RLIMIT_NOFILE) */
+ sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO|SUDO_DEBUG_ERRNO,
+ "sudo_ev_poll");
+ break;
+ case 0:
+ /* Front end will activate timeout events. */
+ sudo_debug_printf(SUDO_DEBUG_INFO, "%s: timeout", __func__);
+ break;
+ default:
+ /* Activate each I/O event that fired. */
+ sudo_debug_printf(SUDO_DEBUG_INFO, "%s: %d fds ready", __func__,
+ nready);
+ 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 = (short)what;
+ sudo_ev_activate(base, ev);
+ }
+ }
+ break;
+ }
+ debug_return_int(nready);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-25 01:38:27 +0000