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https://github.com/samba-team/samba.git
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fa4f1713f9
Signed-off-by: Jeremy Allison <jra@samba.org> Signed-off-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Stefan Metzmacher <metze@samba.org>
934 lines
24 KiB
C
934 lines
24 KiB
C
/*
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Unix SMB/CIFS implementation.
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main select loop and event handling - epoll implementation
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Copyright (C) Andrew Tridgell 2003-2005
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Copyright (C) Stefan Metzmacher 2005-2013
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Copyright (C) Jeremy Allison 2013
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** NOTE! The following LGPL license applies to the tevent
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** library. This does NOT imply that all of Samba is released
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** under the LGPL
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This library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 3 of the License, or (at your option) any later version.
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This library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with this library; if not, see <http://www.gnu.org/licenses/>.
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*/
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#include "replace.h"
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#include "system/filesys.h"
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#include "system/select.h"
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#include "tevent.h"
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#include "tevent_internal.h"
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#include "tevent_util.h"
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struct epoll_event_context {
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/* a pointer back to the generic event_context */
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struct tevent_context *ev;
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/* when using epoll this is the handle from epoll_create */
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int epoll_fd;
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pid_t pid;
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bool panic_force_replay;
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bool *panic_state;
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bool (*panic_fallback)(struct tevent_context *ev, bool replay);
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};
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#define EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT (1<<0)
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#define EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR (1<<1)
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#define EPOLL_ADDITIONAL_FD_FLAG_GOT_ERROR (1<<2)
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#define EPOLL_ADDITIONAL_FD_FLAG_HAS_MPX (1<<3)
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#ifdef TEST_PANIC_FALLBACK
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static int epoll_create_panic_fallback(struct epoll_event_context *epoll_ev,
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int size)
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{
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if (epoll_ev->panic_fallback == NULL) {
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return epoll_create(size);
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}
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/* 50% of the time, fail... */
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if ((random() % 2) == 0) {
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errno = EINVAL;
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return -1;
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}
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return epoll_create(size);
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}
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static int epoll_ctl_panic_fallback(struct epoll_event_context *epoll_ev,
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int epfd, int op, int fd,
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struct epoll_event *event)
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{
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if (epoll_ev->panic_fallback == NULL) {
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return epoll_ctl(epfd, op, fd, event);
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}
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/* 50% of the time, fail... */
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if ((random() % 2) == 0) {
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errno = EINVAL;
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return -1;
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}
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return epoll_ctl(epfd, op, fd, event);
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}
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static int epoll_wait_panic_fallback(struct epoll_event_context *epoll_ev,
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int epfd,
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struct epoll_event *events,
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int maxevents,
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int timeout)
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{
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if (epoll_ev->panic_fallback == NULL) {
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return epoll_wait(epfd, events, maxevents, timeout);
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}
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/* 50% of the time, fail... */
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if ((random() % 2) == 0) {
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errno = EINVAL;
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return -1;
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}
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return epoll_wait(epfd, events, maxevents, timeout);
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}
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#define epoll_create(_size) \
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epoll_create_panic_fallback(epoll_ev, _size)
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#define epoll_ctl(_epfd, _op, _fd, _event) \
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epoll_ctl_panic_fallback(epoll_ev,_epfd, _op, _fd, _event)
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#define epoll_wait(_epfd, _events, _maxevents, _timeout) \
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epoll_wait_panic_fallback(epoll_ev, _epfd, _events, _maxevents, _timeout)
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#endif
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/*
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called to set the panic fallback function.
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*/
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_PRIVATE_ bool tevent_epoll_set_panic_fallback(struct tevent_context *ev,
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bool (*panic_fallback)(struct tevent_context *ev,
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bool replay))
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{
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struct epoll_event_context *epoll_ev;
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if (ev->additional_data == NULL) {
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return false;
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}
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epoll_ev = talloc_get_type(ev->additional_data,
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struct epoll_event_context);
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if (epoll_ev == NULL) {
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return false;
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}
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epoll_ev->panic_fallback = panic_fallback;
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return true;
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}
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/*
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called when a epoll call fails
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*/
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static void epoll_panic(struct epoll_event_context *epoll_ev,
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const char *reason, bool replay)
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{
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struct tevent_context *ev = epoll_ev->ev;
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bool (*panic_fallback)(struct tevent_context *ev, bool replay);
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panic_fallback = epoll_ev->panic_fallback;
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if (epoll_ev->panic_state != NULL) {
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*epoll_ev->panic_state = true;
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}
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if (epoll_ev->panic_force_replay) {
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replay = true;
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}
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TALLOC_FREE(ev->additional_data);
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if (panic_fallback == NULL) {
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tevent_debug(ev, TEVENT_DEBUG_FATAL,
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"%s (%s) replay[%u] - calling abort()\n",
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reason, strerror(errno), (unsigned)replay);
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abort();
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}
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tevent_debug(ev, TEVENT_DEBUG_WARNING,
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"%s (%s) replay[%u] - calling panic_fallback\n",
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reason, strerror(errno), (unsigned)replay);
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if (!panic_fallback(ev, replay)) {
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/* Fallback failed. */
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tevent_debug(ev, TEVENT_DEBUG_FATAL,
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"%s (%s) replay[%u] - calling abort()\n",
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reason, strerror(errno), (unsigned)replay);
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abort();
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}
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}
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/*
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map from TEVENT_FD_* to EPOLLIN/EPOLLOUT
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*/
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static uint32_t epoll_map_flags(uint16_t flags)
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{
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uint32_t ret = 0;
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if (flags & TEVENT_FD_READ) ret |= (EPOLLIN | EPOLLERR | EPOLLHUP);
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if (flags & TEVENT_FD_WRITE) ret |= (EPOLLOUT | EPOLLERR | EPOLLHUP);
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return ret;
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}
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/*
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free the epoll fd
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*/
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static int epoll_ctx_destructor(struct epoll_event_context *epoll_ev)
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{
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close(epoll_ev->epoll_fd);
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epoll_ev->epoll_fd = -1;
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return 0;
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}
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/*
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init the epoll fd
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*/
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static int epoll_init_ctx(struct epoll_event_context *epoll_ev)
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{
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epoll_ev->epoll_fd = epoll_create(64);
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if (epoll_ev->epoll_fd == -1) {
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tevent_debug(epoll_ev->ev, TEVENT_DEBUG_FATAL,
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"Failed to create epoll handle.\n");
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return -1;
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}
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if (!ev_set_close_on_exec(epoll_ev->epoll_fd)) {
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tevent_debug(epoll_ev->ev, TEVENT_DEBUG_WARNING,
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"Failed to set close-on-exec, file descriptor may be leaked to children.\n");
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}
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epoll_ev->pid = getpid();
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talloc_set_destructor(epoll_ev, epoll_ctx_destructor);
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return 0;
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}
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static void epoll_update_event(struct epoll_event_context *epoll_ev, struct tevent_fd *fde);
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/*
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reopen the epoll handle when our pid changes
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see http://junkcode.samba.org/ftp/unpacked/junkcode/epoll_fork.c for an
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demonstration of why this is needed
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*/
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static void epoll_check_reopen(struct epoll_event_context *epoll_ev)
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{
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struct tevent_fd *fde;
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bool *caller_panic_state = epoll_ev->panic_state;
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bool panic_triggered = false;
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if (epoll_ev->pid == getpid()) {
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return;
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}
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close(epoll_ev->epoll_fd);
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epoll_ev->epoll_fd = epoll_create(64);
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if (epoll_ev->epoll_fd == -1) {
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epoll_panic(epoll_ev, "epoll_create() failed", false);
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return;
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}
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if (!ev_set_close_on_exec(epoll_ev->epoll_fd)) {
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tevent_debug(epoll_ev->ev, TEVENT_DEBUG_WARNING,
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"Failed to set close-on-exec, file descriptor may be leaked to children.\n");
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}
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epoll_ev->pid = getpid();
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epoll_ev->panic_state = &panic_triggered;
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for (fde=epoll_ev->ev->fd_events;fde;fde=fde->next) {
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fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT;
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epoll_update_event(epoll_ev, fde);
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if (panic_triggered) {
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if (caller_panic_state != NULL) {
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*caller_panic_state = true;
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}
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return;
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}
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}
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epoll_ev->panic_state = NULL;
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}
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/*
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epoll cannot add the same file descriptor twice, once
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with read, once with write which is allowed by the
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tevent backend. Multiplex the existing fde, flag it
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as such so we can search for the correct fde on
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event triggering.
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*/
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static int epoll_add_multiplex_fd(struct epoll_event_context *epoll_ev,
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struct tevent_fd *add_fde)
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{
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struct epoll_event event;
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struct tevent_fd *mpx_fde;
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int ret;
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/* Find the existing fde that caused the EEXIST error. */
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for (mpx_fde = epoll_ev->ev->fd_events; mpx_fde; mpx_fde = mpx_fde->next) {
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if (mpx_fde->fd != add_fde->fd) {
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continue;
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}
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if (mpx_fde == add_fde) {
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continue;
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}
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break;
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}
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if (mpx_fde == NULL) {
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tevent_debug(epoll_ev->ev, TEVENT_DEBUG_FATAL,
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"can't find multiplex fde for fd[%d]",
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add_fde->fd);
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return -1;
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}
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if (mpx_fde->additional_flags & EPOLL_ADDITIONAL_FD_FLAG_HAS_MPX) {
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/* Logic error. Can't have more than 2 multiplexed fde's. */
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tevent_debug(epoll_ev->ev, TEVENT_DEBUG_FATAL,
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"multiplex fde for fd[%d] is already multiplexed\n",
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mpx_fde->fd);
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return -1;
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}
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/*
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* The multiplex fde must have the same fd, and also
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* already have an epoll event attached.
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*/
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if (!(mpx_fde->additional_flags & EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT)) {
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/* Logic error. Can't have more than 2 multiplexed fde's. */
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tevent_debug(epoll_ev->ev, TEVENT_DEBUG_FATAL,
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"multiplex fde for fd[%d] has no event\n",
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mpx_fde->fd);
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return -1;
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}
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/* Modify the mpx_fde to add in the new flags. */
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ZERO_STRUCT(event);
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event.events = epoll_map_flags(mpx_fde->flags);
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event.events |= epoll_map_flags(add_fde->flags);
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event.data.ptr = mpx_fde;
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ret = epoll_ctl(epoll_ev->epoll_fd, EPOLL_CTL_MOD, mpx_fde->fd, &event);
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if (ret != 0 && errno == EBADF) {
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tevent_debug(epoll_ev->ev, TEVENT_DEBUG_ERROR,
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"EPOLL_CTL_MOD EBADF for "
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"add_fde[%p] mpx_fde[%p] fd[%d] - disabling\n",
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add_fde, mpx_fde, add_fde->fd);
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DLIST_REMOVE(epoll_ev->ev->fd_events, mpx_fde);
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mpx_fde->event_ctx = NULL;
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DLIST_REMOVE(epoll_ev->ev->fd_events, add_fde);
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add_fde->event_ctx = NULL;
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return 0;
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} else if (ret != 0) {
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return ret;
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}
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/*
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* Make each fde->additional_data pointers point at each other
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* so we can look them up from each other. They are now paired.
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*/
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mpx_fde->additional_data = (struct tevent_fd *)add_fde;
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add_fde->additional_data = (struct tevent_fd *)mpx_fde;
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/* Now flag both fde's as being multiplexed. */
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mpx_fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_HAS_MPX;
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add_fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_HAS_MPX;
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/* we need to keep the GOT_ERROR flag */
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if (mpx_fde->additional_flags & EPOLL_ADDITIONAL_FD_FLAG_GOT_ERROR) {
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add_fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_GOT_ERROR;
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}
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return 0;
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}
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/*
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add the epoll event to the given fd_event
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*/
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static void epoll_add_event(struct epoll_event_context *epoll_ev, struct tevent_fd *fde)
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{
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struct epoll_event event;
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int ret;
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struct tevent_fd *mpx_fde = NULL;
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fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT;
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fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
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if (fde->additional_flags & EPOLL_ADDITIONAL_FD_FLAG_HAS_MPX) {
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/*
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* This is a multiplexed fde, we need to include both
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* flags in the modified event.
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*/
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mpx_fde = talloc_get_type_abort(fde->additional_data,
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struct tevent_fd);
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mpx_fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT;
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mpx_fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
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}
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ZERO_STRUCT(event);
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event.events = epoll_map_flags(fde->flags);
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if (mpx_fde != NULL) {
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event.events |= epoll_map_flags(mpx_fde->flags);
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}
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event.data.ptr = fde;
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ret = epoll_ctl(epoll_ev->epoll_fd, EPOLL_CTL_ADD, fde->fd, &event);
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if (ret != 0 && errno == EBADF) {
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tevent_debug(epoll_ev->ev, TEVENT_DEBUG_ERROR,
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"EPOLL_CTL_ADD EBADF for "
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"fde[%p] mpx_fde[%p] fd[%d] - disabling\n",
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fde, mpx_fde, fde->fd);
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DLIST_REMOVE(epoll_ev->ev->fd_events, fde);
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fde->event_ctx = NULL;
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if (mpx_fde != NULL) {
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DLIST_REMOVE(epoll_ev->ev->fd_events, mpx_fde);
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mpx_fde->event_ctx = NULL;
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}
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return;
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} else if (ret != 0) {
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epoll_panic(epoll_ev, "EPOLL_CTL_ADD failed", false);
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return;
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}
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fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT;
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/* only if we want to read we want to tell the event handler about errors */
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if (fde->flags & TEVENT_FD_READ) {
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fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
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}
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if (mpx_fde == NULL) {
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return;
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}
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mpx_fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT;
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/* only if we want to read we want to tell the event handler about errors */
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if (mpx_fde->flags & TEVENT_FD_READ) {
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mpx_fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
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}
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}
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/*
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delete the epoll event for given fd_event
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*/
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static void epoll_del_event(struct epoll_event_context *epoll_ev, struct tevent_fd *fde)
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{
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struct epoll_event event;
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int ret;
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struct tevent_fd *mpx_fde = NULL;
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fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT;
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fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
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if (fde->additional_flags & EPOLL_ADDITIONAL_FD_FLAG_HAS_MPX) {
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/*
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* This is a multiplexed fde, we need to modify both events.
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*/
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mpx_fde = talloc_get_type_abort(fde->additional_data,
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struct tevent_fd);
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mpx_fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT;
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mpx_fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
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}
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ZERO_STRUCT(event);
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ret = epoll_ctl(epoll_ev->epoll_fd, EPOLL_CTL_DEL, fde->fd, &event);
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if (ret != 0 && errno == ENOENT) {
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/*
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* This can happen after a epoll_check_reopen
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* within epoll_event_fd_destructor.
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*/
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tevent_debug(epoll_ev->ev, TEVENT_DEBUG_TRACE,
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"EPOLL_CTL_DEL ignoring ENOENT for fd[%d]\n",
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fde->fd);
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return;
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} else if (ret != 0 && errno == EBADF) {
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tevent_debug(epoll_ev->ev, TEVENT_DEBUG_WARNING,
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"EPOLL_CTL_DEL EBADF for "
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"fde[%p] mpx_fde[%p] fd[%d] - disabling\n",
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fde, mpx_fde, fde->fd);
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DLIST_REMOVE(epoll_ev->ev->fd_events, fde);
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fde->event_ctx = NULL;
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if (mpx_fde != NULL) {
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DLIST_REMOVE(epoll_ev->ev->fd_events, mpx_fde);
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mpx_fde->event_ctx = NULL;
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}
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return;
|
|
} else if (ret != 0) {
|
|
epoll_panic(epoll_ev, "EPOLL_CTL_DEL failed", false);
|
|
return;
|
|
}
|
|
}
|
|
|
|
/*
|
|
change the epoll event to the given fd_event
|
|
*/
|
|
static void epoll_mod_event(struct epoll_event_context *epoll_ev, struct tevent_fd *fde)
|
|
{
|
|
struct tevent_fd *mpx_fde = NULL;
|
|
struct epoll_event event;
|
|
int ret;
|
|
|
|
fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT;
|
|
fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
|
|
|
|
if (fde->additional_flags & EPOLL_ADDITIONAL_FD_FLAG_HAS_MPX) {
|
|
/*
|
|
* This is a multiplexed fde, we need to include both
|
|
* flags in the modified event.
|
|
*/
|
|
mpx_fde = talloc_get_type_abort(fde->additional_data,
|
|
struct tevent_fd);
|
|
|
|
mpx_fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT;
|
|
mpx_fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
|
|
}
|
|
|
|
ZERO_STRUCT(event);
|
|
event.events = epoll_map_flags(fde->flags);
|
|
if (mpx_fde != NULL) {
|
|
event.events |= epoll_map_flags(mpx_fde->flags);
|
|
}
|
|
event.data.ptr = fde;
|
|
ret = epoll_ctl(epoll_ev->epoll_fd, EPOLL_CTL_MOD, fde->fd, &event);
|
|
if (ret != 0 && errno == EBADF) {
|
|
tevent_debug(epoll_ev->ev, TEVENT_DEBUG_ERROR,
|
|
"EPOLL_CTL_MOD EBADF for "
|
|
"fde[%p] mpx_fde[%p] fd[%d] - disabling\n",
|
|
fde, mpx_fde, fde->fd);
|
|
DLIST_REMOVE(epoll_ev->ev->fd_events, fde);
|
|
fde->event_ctx = NULL;
|
|
if (mpx_fde != NULL) {
|
|
DLIST_REMOVE(epoll_ev->ev->fd_events, mpx_fde);
|
|
mpx_fde->event_ctx = NULL;
|
|
}
|
|
return;
|
|
} else if (ret != 0) {
|
|
epoll_panic(epoll_ev, "EPOLL_CTL_MOD failed", false);
|
|
return;
|
|
}
|
|
|
|
fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT;
|
|
/* only if we want to read we want to tell the event handler about errors */
|
|
if (fde->flags & TEVENT_FD_READ) {
|
|
fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
|
|
}
|
|
|
|
if (mpx_fde == NULL) {
|
|
return;
|
|
}
|
|
|
|
mpx_fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT;
|
|
/* only if we want to read we want to tell the event handler about errors */
|
|
if (mpx_fde->flags & TEVENT_FD_READ) {
|
|
mpx_fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
|
|
}
|
|
}
|
|
|
|
static void epoll_update_event(struct epoll_event_context *epoll_ev, struct tevent_fd *fde)
|
|
{
|
|
bool got_error = (fde->additional_flags & EPOLL_ADDITIONAL_FD_FLAG_GOT_ERROR);
|
|
bool want_read = (fde->flags & TEVENT_FD_READ);
|
|
bool want_write= (fde->flags & TEVENT_FD_WRITE);
|
|
struct tevent_fd *mpx_fde = NULL;
|
|
|
|
if (fde->additional_flags & EPOLL_ADDITIONAL_FD_FLAG_HAS_MPX) {
|
|
/*
|
|
* work out what the multiplexed fde wants.
|
|
*/
|
|
mpx_fde = talloc_get_type_abort(fde->additional_data,
|
|
struct tevent_fd);
|
|
|
|
if (mpx_fde->flags & TEVENT_FD_READ) {
|
|
want_read = true;
|
|
}
|
|
|
|
if (mpx_fde->flags & TEVENT_FD_WRITE) {
|
|
want_write = true;
|
|
}
|
|
}
|
|
|
|
/* there's already an event */
|
|
if (fde->additional_flags & EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT) {
|
|
if (want_read || (want_write && !got_error)) {
|
|
epoll_mod_event(epoll_ev, fde);
|
|
return;
|
|
}
|
|
/*
|
|
* if we want to match the select behavior, we need to remove the epoll_event
|
|
* when the caller isn't interested in events.
|
|
*
|
|
* this is because epoll reports EPOLLERR and EPOLLHUP, even without asking for them
|
|
*/
|
|
epoll_del_event(epoll_ev, fde);
|
|
return;
|
|
}
|
|
|
|
/* there's no epoll_event attached to the fde */
|
|
if (want_read || (want_write && !got_error)) {
|
|
epoll_add_event(epoll_ev, fde);
|
|
return;
|
|
}
|
|
}
|
|
|
|
/*
|
|
Cope with epoll returning EPOLLHUP|EPOLLERR on an event.
|
|
Return true if there's nothing else to do, false if
|
|
this event needs further handling.
|
|
*/
|
|
static bool epoll_handle_hup_or_err(struct epoll_event_context *epoll_ev,
|
|
struct tevent_fd *fde)
|
|
{
|
|
if (fde == NULL) {
|
|
/* Nothing to do if no event. */
|
|
return true;
|
|
}
|
|
|
|
fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_GOT_ERROR;
|
|
/*
|
|
* if we only wait for TEVENT_FD_WRITE, we should not tell the
|
|
* event handler about it, and remove the epoll_event,
|
|
* as we only report errors when waiting for read events,
|
|
* to match the select() behavior
|
|
*/
|
|
if (!(fde->additional_flags & EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR)) {
|
|
/*
|
|
* Do the same as the poll backend and
|
|
* remove the writeable flag.
|
|
*/
|
|
fde->flags &= ~TEVENT_FD_WRITE;
|
|
return true;
|
|
}
|
|
/* This has TEVENT_FD_READ set, we're not finished. */
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
event loop handling using epoll
|
|
*/
|
|
static int epoll_event_loop(struct epoll_event_context *epoll_ev, struct timeval *tvalp)
|
|
{
|
|
int ret, i;
|
|
#define MAXEVENTS 1
|
|
struct epoll_event events[MAXEVENTS];
|
|
int timeout = -1;
|
|
int wait_errno;
|
|
|
|
if (tvalp) {
|
|
/* it's better to trigger timed events a bit later than too early */
|
|
timeout = ((tvalp->tv_usec+999) / 1000) + (tvalp->tv_sec*1000);
|
|
}
|
|
|
|
if (epoll_ev->ev->signal_events &&
|
|
tevent_common_check_signal(epoll_ev->ev)) {
|
|
return 0;
|
|
}
|
|
|
|
tevent_trace_point_callback(epoll_ev->ev, TEVENT_TRACE_BEFORE_WAIT);
|
|
ret = epoll_wait(epoll_ev->epoll_fd, events, MAXEVENTS, timeout);
|
|
wait_errno = errno;
|
|
tevent_trace_point_callback(epoll_ev->ev, TEVENT_TRACE_AFTER_WAIT);
|
|
|
|
if (ret == -1 && wait_errno == EINTR && epoll_ev->ev->signal_events) {
|
|
if (tevent_common_check_signal(epoll_ev->ev)) {
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
if (ret == -1 && wait_errno != EINTR) {
|
|
epoll_panic(epoll_ev, "epoll_wait() failed", true);
|
|
return -1;
|
|
}
|
|
|
|
if (ret == 0 && tvalp) {
|
|
/* we don't care about a possible delay here */
|
|
tevent_common_loop_timer_delay(epoll_ev->ev);
|
|
return 0;
|
|
}
|
|
|
|
for (i=0;i<ret;i++) {
|
|
struct tevent_fd *fde = talloc_get_type(events[i].data.ptr,
|
|
struct tevent_fd);
|
|
uint16_t flags = 0;
|
|
struct tevent_fd *mpx_fde = NULL;
|
|
|
|
if (fde == NULL) {
|
|
epoll_panic(epoll_ev, "epoll_wait() gave bad data", true);
|
|
return -1;
|
|
}
|
|
if (fde->additional_flags & EPOLL_ADDITIONAL_FD_FLAG_HAS_MPX) {
|
|
/*
|
|
* Save off the multiplexed event in case we need
|
|
* to use it to call the handler function.
|
|
*/
|
|
mpx_fde = talloc_get_type_abort(fde->additional_data,
|
|
struct tevent_fd);
|
|
}
|
|
if (events[i].events & (EPOLLHUP|EPOLLERR)) {
|
|
bool handled_fde = epoll_handle_hup_or_err(epoll_ev, fde);
|
|
bool handled_mpx = epoll_handle_hup_or_err(epoll_ev, mpx_fde);
|
|
|
|
if (handled_fde && handled_mpx) {
|
|
epoll_update_event(epoll_ev, fde);
|
|
continue;
|
|
}
|
|
|
|
if (!handled_mpx) {
|
|
/*
|
|
* If the mpx event was the one that needs
|
|
* further handling, it's the TEVENT_FD_READ
|
|
* event so switch over and call that handler.
|
|
*/
|
|
fde = mpx_fde;
|
|
mpx_fde = NULL;
|
|
}
|
|
flags |= TEVENT_FD_READ;
|
|
}
|
|
if (events[i].events & EPOLLIN) flags |= TEVENT_FD_READ;
|
|
if (events[i].events & EPOLLOUT) flags |= TEVENT_FD_WRITE;
|
|
|
|
if (mpx_fde) {
|
|
/* Ensure we got the right fde. */
|
|
if ((flags & fde->flags) == 0) {
|
|
fde = mpx_fde;
|
|
mpx_fde = NULL;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* make sure we only pass the flags
|
|
* the handler is expecting.
|
|
*/
|
|
flags &= fde->flags;
|
|
if (flags) {
|
|
fde->handler(epoll_ev->ev, fde, flags, fde->private_data);
|
|
break;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
create a epoll_event_context structure.
|
|
*/
|
|
static int epoll_event_context_init(struct tevent_context *ev)
|
|
{
|
|
int ret;
|
|
struct epoll_event_context *epoll_ev;
|
|
|
|
/*
|
|
* We might be called during tevent_re_initialise()
|
|
* which means we need to free our old additional_data.
|
|
*/
|
|
TALLOC_FREE(ev->additional_data);
|
|
|
|
epoll_ev = talloc_zero(ev, struct epoll_event_context);
|
|
if (!epoll_ev) return -1;
|
|
epoll_ev->ev = ev;
|
|
epoll_ev->epoll_fd = -1;
|
|
|
|
ret = epoll_init_ctx(epoll_ev);
|
|
if (ret != 0) {
|
|
talloc_free(epoll_ev);
|
|
return ret;
|
|
}
|
|
|
|
ev->additional_data = epoll_ev;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
destroy an fd_event
|
|
*/
|
|
static int epoll_event_fd_destructor(struct tevent_fd *fde)
|
|
{
|
|
struct tevent_context *ev = fde->event_ctx;
|
|
struct epoll_event_context *epoll_ev = NULL;
|
|
bool panic_triggered = false;
|
|
struct tevent_fd *mpx_fde = NULL;
|
|
int flags = fde->flags;
|
|
|
|
if (ev == NULL) {
|
|
return tevent_common_fd_destructor(fde);
|
|
}
|
|
|
|
epoll_ev = talloc_get_type_abort(ev->additional_data,
|
|
struct epoll_event_context);
|
|
|
|
/*
|
|
* we must remove the event from the list
|
|
* otherwise a panic fallback handler may
|
|
* reuse invalid memory
|
|
*/
|
|
DLIST_REMOVE(ev->fd_events, fde);
|
|
|
|
if (fde->additional_flags & EPOLL_ADDITIONAL_FD_FLAG_HAS_MPX) {
|
|
mpx_fde = talloc_get_type_abort(fde->additional_data,
|
|
struct tevent_fd);
|
|
|
|
fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_HAS_MPX;
|
|
mpx_fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_HAS_MPX;
|
|
|
|
fde->additional_data = NULL;
|
|
mpx_fde->additional_data = NULL;
|
|
|
|
fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT;
|
|
}
|
|
|
|
epoll_ev->panic_state = &panic_triggered;
|
|
epoll_check_reopen(epoll_ev);
|
|
if (panic_triggered) {
|
|
return tevent_common_fd_destructor(fde);
|
|
}
|
|
|
|
if (mpx_fde != NULL) {
|
|
epoll_update_event(epoll_ev, mpx_fde);
|
|
if (panic_triggered) {
|
|
return tevent_common_fd_destructor(fde);
|
|
}
|
|
}
|
|
|
|
fde->flags = 0;
|
|
epoll_update_event(epoll_ev, fde);
|
|
fde->flags = flags;
|
|
if (panic_triggered) {
|
|
return tevent_common_fd_destructor(fde);
|
|
}
|
|
epoll_ev->panic_state = NULL;
|
|
|
|
return tevent_common_fd_destructor(fde);
|
|
}
|
|
|
|
/*
|
|
add a fd based event
|
|
return NULL on failure (memory allocation error)
|
|
*/
|
|
static struct tevent_fd *epoll_event_add_fd(struct tevent_context *ev, TALLOC_CTX *mem_ctx,
|
|
int fd, uint16_t flags,
|
|
tevent_fd_handler_t handler,
|
|
void *private_data,
|
|
const char *handler_name,
|
|
const char *location)
|
|
{
|
|
struct epoll_event_context *epoll_ev = talloc_get_type(ev->additional_data,
|
|
struct epoll_event_context);
|
|
struct tevent_fd *fde;
|
|
bool panic_triggered = false;
|
|
|
|
fde = tevent_common_add_fd(ev, mem_ctx, fd, flags,
|
|
handler, private_data,
|
|
handler_name, location);
|
|
if (!fde) return NULL;
|
|
|
|
talloc_set_destructor(fde, epoll_event_fd_destructor);
|
|
|
|
epoll_ev->panic_state = &panic_triggered;
|
|
epoll_check_reopen(epoll_ev);
|
|
if (panic_triggered) {
|
|
return fde;
|
|
}
|
|
epoll_ev->panic_state = NULL;
|
|
|
|
epoll_update_event(epoll_ev, fde);
|
|
|
|
return fde;
|
|
}
|
|
|
|
/*
|
|
set the fd event flags
|
|
*/
|
|
static void epoll_event_set_fd_flags(struct tevent_fd *fde, uint16_t flags)
|
|
{
|
|
struct tevent_context *ev;
|
|
struct epoll_event_context *epoll_ev;
|
|
bool panic_triggered = false;
|
|
|
|
if (fde->flags == flags) return;
|
|
|
|
ev = fde->event_ctx;
|
|
epoll_ev = talloc_get_type(ev->additional_data, struct epoll_event_context);
|
|
|
|
fde->flags = flags;
|
|
|
|
epoll_ev->panic_state = &panic_triggered;
|
|
epoll_check_reopen(epoll_ev);
|
|
if (panic_triggered) {
|
|
return;
|
|
}
|
|
epoll_ev->panic_state = NULL;
|
|
|
|
epoll_update_event(epoll_ev, fde);
|
|
}
|
|
|
|
/*
|
|
do a single event loop using the events defined in ev
|
|
*/
|
|
static int epoll_event_loop_once(struct tevent_context *ev, const char *location)
|
|
{
|
|
struct epoll_event_context *epoll_ev = talloc_get_type(ev->additional_data,
|
|
struct epoll_event_context);
|
|
struct timeval tval;
|
|
bool panic_triggered = false;
|
|
|
|
if (ev->signal_events &&
|
|
tevent_common_check_signal(ev)) {
|
|
return 0;
|
|
}
|
|
|
|
if (ev->immediate_events &&
|
|
tevent_common_loop_immediate(ev)) {
|
|
return 0;
|
|
}
|
|
|
|
tval = tevent_common_loop_timer_delay(ev);
|
|
if (tevent_timeval_is_zero(&tval)) {
|
|
return 0;
|
|
}
|
|
|
|
epoll_ev->panic_state = &panic_triggered;
|
|
epoll_ev->panic_force_replay = true;
|
|
epoll_check_reopen(epoll_ev);
|
|
if (panic_triggered) {
|
|
errno = EINVAL;
|
|
return -1;
|
|
}
|
|
epoll_ev->panic_force_replay = false;
|
|
epoll_ev->panic_state = NULL;
|
|
|
|
return epoll_event_loop(epoll_ev, &tval);
|
|
}
|
|
|
|
static const struct tevent_ops epoll_event_ops = {
|
|
.context_init = epoll_event_context_init,
|
|
.add_fd = epoll_event_add_fd,
|
|
.set_fd_close_fn = tevent_common_fd_set_close_fn,
|
|
.get_fd_flags = tevent_common_fd_get_flags,
|
|
.set_fd_flags = epoll_event_set_fd_flags,
|
|
.add_timer = tevent_common_add_timer,
|
|
.schedule_immediate = tevent_common_schedule_immediate,
|
|
.add_signal = tevent_common_add_signal,
|
|
.loop_once = epoll_event_loop_once,
|
|
.loop_wait = tevent_common_loop_wait,
|
|
};
|
|
|
|
_PRIVATE_ bool tevent_epoll_init(void)
|
|
{
|
|
return tevent_register_backend("epoll", &epoll_event_ops);
|
|
}
|