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-rw-r--r--tevent/tevent_standard.c607
1 files changed, 0 insertions, 607 deletions
diff --git a/tevent/tevent_standard.c b/tevent/tevent_standard.c
deleted file mode 100644
index c63d09217..000000000
--- a/tevent/tevent_standard.c
+++ /dev/null
@@ -1,607 +0,0 @@
-/*
- Unix SMB/CIFS implementation.
- main select loop and event handling
- Copyright (C) Andrew Tridgell 2003-2005
- Copyright (C) Stefan Metzmacher 2005
-
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 3 of the License, or
- (at your option) any later version.
-
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with this program. If not, see <http://www.gnu.org/licenses/>.
-*/
-
-/*
- This is SAMBA's default event loop code
-
- - we try to use epoll if configure detected support for it
- otherwise we use select()
- - if epoll is broken on the system or the kernel doesn't support it
- at runtime we fallback to select()
-*/
-
-#include "replace.h"
-#include "system/filesys.h"
-#include "system/network.h"
-#include "system/select.h" /* needed for HAVE_EVENTS_EPOLL */
-#include "tevent.h"
-#include "tevent_util.h"
-#include "tevent_internal.h"
-
-struct std_event_context {
- /* a pointer back to the generic event_context */
- struct event_context *ev;
-
- /* list of filedescriptor events */
- struct fd_event *fd_events;
-
- /* the maximum file descriptor number in fd_events */
- int maxfd;
-
- /* information for exiting from the event loop */
- int exit_code;
-
- /* this is changed by the destructors for the fd event
- type. It is used to detect event destruction by event
- handlers, which means the code that is calling the event
- handler needs to assume that the linked list is no longer
- valid
- */
- uint32_t destruction_count;
-
- /* when using epoll this is the handle from epoll_create */
- int epoll_fd;
-
- /* our pid at the time the epoll_fd was created */
- pid_t pid;
-};
-
-/* use epoll if it is available */
-#if HAVE_EVENTS_EPOLL
-/*
- called when a epoll call fails, and we should fallback
- to using select
-*/
-static void epoll_fallback_to_select(struct std_event_context *std_ev, const char *reason)
-{
- ev_debug(std_ev->ev, EV_DEBUG_FATAL,
- "%s (%s) - falling back to select()\n",
- reason, strerror(errno));
- close(std_ev->epoll_fd);
- std_ev->epoll_fd = -1;
- talloc_set_destructor(std_ev, NULL);
-}
-
-/*
- map from EVENT_FD_* to EPOLLIN/EPOLLOUT
-*/
-static uint32_t epoll_map_flags(uint16_t flags)
-{
- uint32_t ret = 0;
- if (flags & EVENT_FD_READ) ret |= (EPOLLIN | EPOLLERR | EPOLLHUP);
- if (flags & EVENT_FD_WRITE) ret |= (EPOLLOUT | EPOLLERR | EPOLLHUP);
- return ret;
-}
-
-/*
- free the epoll fd
-*/
-static int epoll_ctx_destructor(struct std_event_context *std_ev)
-{
- if (std_ev->epoll_fd != -1) {
- close(std_ev->epoll_fd);
- }
- std_ev->epoll_fd = -1;
- return 0;
-}
-
-/*
- init the epoll fd
-*/
-static void epoll_init_ctx(struct std_event_context *std_ev)
-{
- std_ev->epoll_fd = epoll_create(64);
- std_ev->pid = getpid();
- talloc_set_destructor(std_ev, epoll_ctx_destructor);
-}
-
-static void epoll_add_event(struct std_event_context *std_ev, struct fd_event *fde);
-
-/*
- reopen the epoll handle when our pid changes
- see http://junkcode.samba.org/ftp/unpacked/junkcode/epoll_fork.c for an
- demonstration of why this is needed
- */
-static void epoll_check_reopen(struct std_event_context *std_ev)
-{
- struct fd_event *fde;
-
- if (std_ev->pid == getpid()) {
- return;
- }
-
- close(std_ev->epoll_fd);
- std_ev->epoll_fd = epoll_create(64);
- if (std_ev->epoll_fd == -1) {
- ev_debug(std_ev->ev, EV_DEBUG_FATAL,
- "Failed to recreate epoll handle after fork\n");
- return;
- }
- std_ev->pid = getpid();
- for (fde=std_ev->fd_events;fde;fde=fde->next) {
- epoll_add_event(std_ev, fde);
- }
-}
-
-#define EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT (1<<0)
-#define EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR (1<<1)
-#define EPOLL_ADDITIONAL_FD_FLAG_GOT_ERROR (1<<2)
-
-/*
- add the epoll event to the given fd_event
-*/
-static void epoll_add_event(struct std_event_context *std_ev, struct fd_event *fde)
-{
- struct epoll_event event;
- if (std_ev->epoll_fd == -1) return;
-
- fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
-
- /* if we don't want events yet, don't add an epoll_event */
- if (fde->flags == 0) return;
-
- ZERO_STRUCT(event);
- event.events = epoll_map_flags(fde->flags);
- event.data.ptr = fde;
- if (epoll_ctl(std_ev->epoll_fd, EPOLL_CTL_ADD, fde->fd, &event) != 0) {
- epoll_fallback_to_select(std_ev, "EPOLL_CTL_ADD failed");
- }
- 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 & EVENT_FD_READ) {
- fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
- }
-}
-
-/*
- delete the epoll event for given fd_event
-*/
-static void epoll_del_event(struct std_event_context *std_ev, struct fd_event *fde)
-{
- struct epoll_event event;
- if (std_ev->epoll_fd == -1) return;
-
- fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
-
- /* if there's no epoll_event, we don't need to delete it */
- if (!(fde->additional_flags & EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT)) return;
-
- ZERO_STRUCT(event);
- event.events = epoll_map_flags(fde->flags);
- event.data.ptr = fde;
- epoll_ctl(std_ev->epoll_fd, EPOLL_CTL_DEL, fde->fd, &event);
- fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT;
-}
-
-/*
- change the epoll event to the given fd_event
-*/
-static void epoll_mod_event(struct std_event_context *std_ev, struct fd_event *fde)
-{
- struct epoll_event event;
- if (std_ev->epoll_fd == -1) return;
-
- fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
-
- ZERO_STRUCT(event);
- event.events = epoll_map_flags(fde->flags);
- event.data.ptr = fde;
- if (epoll_ctl(std_ev->epoll_fd, EPOLL_CTL_MOD, fde->fd, &event) != 0) {
- epoll_fallback_to_select(std_ev, "EPOLL_CTL_MOD failed");
- }
-
- /* only if we want to read we want to tell the event handler about errors */
- if (fde->flags & EVENT_FD_READ) {
- fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
- }
-}
-
-static void epoll_change_event(struct std_event_context *std_ev, struct fd_event *fde)
-{
- bool got_error = (fde->additional_flags & EPOLL_ADDITIONAL_FD_FLAG_GOT_ERROR);
- bool want_read = (fde->flags & EVENT_FD_READ);
- bool want_write= (fde->flags & EVENT_FD_WRITE);
-
- if (std_ev->epoll_fd == -1) return;
-
- fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
-
- /* 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(std_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(std_ev, fde);
- return;
- }
-
- /* there's no epoll_event attached to the fde */
- if (want_read || (want_write && !got_error)) {
- epoll_add_event(std_ev, fde);
- return;
- }
-}
-
-/*
- event loop handling using epoll
-*/
-static int epoll_event_loop(struct std_event_context *std_ev, struct timeval *tvalp)
-{
- int ret, i;
-#define MAXEVENTS 8
- struct epoll_event events[MAXEVENTS];
- uint32_t destruction_count = ++std_ev->destruction_count;
- int timeout = -1;
-
- if (std_ev->epoll_fd == -1) return -1;
-
- if (tvalp) {
- /* it's better to trigger timed events a bit later than to early */
- timeout = ((tvalp->tv_usec+999) / 1000) + (tvalp->tv_sec*1000);
- }
-
- if (std_ev->ev->num_signal_handlers &&
- common_event_check_signal(std_ev->ev)) {
- return 0;
- }
-
- ret = epoll_wait(std_ev->epoll_fd, events, MAXEVENTS, timeout);
-
- if (ret == -1 && errno == EINTR && std_ev->ev->num_signal_handlers) {
- if (common_event_check_signal(std_ev->ev)) {
- return 0;
- }
- }
-
- if (ret == -1 && errno != EINTR) {
- epoll_fallback_to_select(std_ev, "epoll_wait() failed");
- return -1;
- }
-
- if (ret == 0 && tvalp) {
- /* we don't care about a possible delay here */
- common_event_loop_timer_delay(std_ev->ev);
- return 0;
- }
-
- for (i=0;i<ret;i++) {
- struct fd_event *fde = talloc_get_type(events[i].data.ptr,
- struct fd_event);
- uint16_t flags = 0;
-
- if (fde == NULL) {
- epoll_fallback_to_select(std_ev, "epoll_wait() gave bad data");
- return -1;
- }
- if (events[i].events & (EPOLLHUP|EPOLLERR)) {
- fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_GOT_ERROR;
- /*
- * if we only wait for EVENT_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)) {
- epoll_del_event(std_ev, fde);
- continue;
- }
- flags |= EVENT_FD_READ;
- }
- if (events[i].events & EPOLLIN) flags |= EVENT_FD_READ;
- if (events[i].events & EPOLLOUT) flags |= EVENT_FD_WRITE;
- if (flags) {
- fde->handler(std_ev->ev, fde, flags, fde->private_data);
- if (destruction_count != std_ev->destruction_count) {
- break;
- }
- }
- }
-
- return 0;
-}
-#else
-#define epoll_init_ctx(std_ev)
-#define epoll_add_event(std_ev,fde)
-#define epoll_del_event(std_ev,fde)
-#define epoll_change_event(std_ev,fde)
-#define epoll_event_loop(std_ev,tvalp) (-1)
-#define epoll_check_reopen(std_ev)
-#endif
-
-/*
- create a std_event_context structure.
-*/
-static int std_event_context_init(struct event_context *ev)
-{
- struct std_event_context *std_ev;
-
- std_ev = talloc_zero(ev, struct std_event_context);
- if (!std_ev) return -1;
- std_ev->ev = ev;
- std_ev->epoll_fd = -1;
-
- epoll_init_ctx(std_ev);
-
- ev->additional_data = std_ev;
- return 0;
-}
-
-/*
- recalculate the maxfd
-*/
-static void calc_maxfd(struct std_event_context *std_ev)
-{
- struct fd_event *fde;
-
- std_ev->maxfd = 0;
- for (fde = std_ev->fd_events; fde; fde = fde->next) {
- if (fde->fd > std_ev->maxfd) {
- std_ev->maxfd = fde->fd;
- }
- }
-}
-
-
-/* to mark the ev->maxfd invalid
- * this means we need to recalculate it
- */
-#define EVENT_INVALID_MAXFD (-1)
-
-/*
- destroy an fd_event
-*/
-static int std_event_fd_destructor(struct fd_event *fde)
-{
- struct event_context *ev = fde->event_ctx;
- struct std_event_context *std_ev = talloc_get_type(ev->additional_data,
- struct std_event_context);
-
- epoll_check_reopen(std_ev);
-
- if (std_ev->maxfd == fde->fd) {
- std_ev->maxfd = EVENT_INVALID_MAXFD;
- }
-
- DLIST_REMOVE(std_ev->fd_events, fde);
- std_ev->destruction_count++;
-
- epoll_del_event(std_ev, fde);
-
- if (fde->flags & EVENT_FD_AUTOCLOSE) {
- close(fde->fd);
- fde->fd = -1;
- }
-
- return 0;
-}
-
-/*
- add a fd based event
- return NULL on failure (memory allocation error)
-*/
-static struct fd_event *std_event_add_fd(struct event_context *ev, TALLOC_CTX *mem_ctx,
- int fd, uint16_t flags,
- event_fd_handler_t handler,
- void *private_data)
-{
- struct std_event_context *std_ev = talloc_get_type(ev->additional_data,
- struct std_event_context);
- struct fd_event *fde;
-
- epoll_check_reopen(std_ev);
-
- fde = talloc(mem_ctx?mem_ctx:ev, struct fd_event);
- if (!fde) return NULL;
-
- fde->event_ctx = ev;
- fde->fd = fd;
- fde->flags = flags;
- fde->handler = handler;
- fde->private_data = private_data;
- fde->additional_flags = 0;
- fde->additional_data = NULL;
-
- DLIST_ADD(std_ev->fd_events, fde);
- if ((std_ev->maxfd != EVENT_INVALID_MAXFD)
- && (fde->fd > std_ev->maxfd)) {
- std_ev->maxfd = fde->fd;
- }
- talloc_set_destructor(fde, std_event_fd_destructor);
-
- epoll_add_event(std_ev, fde);
-
- return fde;
-}
-
-
-/*
- return the fd event flags
-*/
-static uint16_t std_event_get_fd_flags(struct fd_event *fde)
-{
- return fde->flags;
-}
-
-/*
- set the fd event flags
-*/
-static void std_event_set_fd_flags(struct fd_event *fde, uint16_t flags)
-{
- struct event_context *ev;
- struct std_event_context *std_ev;
-
- if (fde->flags == flags) return;
-
- ev = fde->event_ctx;
- std_ev = talloc_get_type(ev->additional_data, struct std_event_context);
-
- fde->flags = flags;
-
- epoll_check_reopen(std_ev);
-
- epoll_change_event(std_ev, fde);
-}
-
-/*
- event loop handling using select()
-*/
-static int std_event_loop_select(struct std_event_context *std_ev, struct timeval *tvalp)
-{
- fd_set r_fds, w_fds;
- struct fd_event *fde;
- int selrtn;
- uint32_t destruction_count = ++std_ev->destruction_count;
-
- /* we maybe need to recalculate the maxfd */
- if (std_ev->maxfd == EVENT_INVALID_MAXFD) {
- calc_maxfd(std_ev);
- }
-
- FD_ZERO(&r_fds);
- FD_ZERO(&w_fds);
-
- /* setup any fd events */
- for (fde = std_ev->fd_events; fde; fde = fde->next) {
- if (fde->flags & EVENT_FD_READ) {
- FD_SET(fde->fd, &r_fds);
- }
- if (fde->flags & EVENT_FD_WRITE) {
- FD_SET(fde->fd, &w_fds);
- }
- }
-
- if (std_ev->ev->num_signal_handlers &&
- common_event_check_signal(std_ev->ev)) {
- return 0;
- }
-
- selrtn = select(std_ev->maxfd+1, &r_fds, &w_fds, NULL, tvalp);
-
- if (selrtn == -1 && errno == EINTR &&
- std_ev->ev->num_signal_handlers) {
- common_event_check_signal(std_ev->ev);
- return 0;
- }
-
- if (selrtn == -1 && errno == EBADF) {
- /* the socket is dead! this should never
- happen as the socket should have first been
- made readable and that should have removed
- the event, so this must be a bug. This is a
- fatal error. */
- ev_debug(std_ev->ev, EV_DEBUG_FATAL,
- "ERROR: EBADF on std_event_loop_once\n");
- std_ev->exit_code = EBADF;
- return -1;
- }
-
- if (selrtn == 0 && tvalp) {
- /* we don't care about a possible delay here */
- common_event_loop_timer_delay(std_ev->ev);
- return 0;
- }
-
- if (selrtn > 0) {
- /* at least one file descriptor is ready - check
- which ones and call the handler, being careful to allow
- the handler to remove itself when called */
- for (fde = std_ev->fd_events; fde; fde = fde->next) {
- uint16_t flags = 0;
-
- if (FD_ISSET(fde->fd, &r_fds)) flags |= EVENT_FD_READ;
- if (FD_ISSET(fde->fd, &w_fds)) flags |= EVENT_FD_WRITE;
- if (flags) {
- fde->handler(std_ev->ev, fde, flags, fde->private_data);
- if (destruction_count != std_ev->destruction_count) {
- break;
- }
- }
- }
- }
-
- return 0;
-}
-
-/*
- do a single event loop using the events defined in ev
-*/
-static int std_event_loop_once(struct event_context *ev)
-{
- struct std_event_context *std_ev = talloc_get_type(ev->additional_data,
- struct std_event_context);
- struct timeval tval;
-
- tval = common_event_loop_timer_delay(ev);
- if (ev_timeval_is_zero(&tval)) {
- return 0;
- }
-
- epoll_check_reopen(std_ev);
-
- if (epoll_event_loop(std_ev, &tval) == 0) {
- return 0;
- }
-
- return std_event_loop_select(std_ev, &tval);
-}
-
-/*
- return on failure or (with 0) if all fd events are removed
-*/
-static int std_event_loop_wait(struct event_context *ev)
-{
- struct std_event_context *std_ev = talloc_get_type(ev->additional_data,
- struct std_event_context);
- std_ev->exit_code = 0;
-
- while (std_ev->fd_events && std_ev->exit_code == 0) {
- if (std_event_loop_once(ev) != 0) {
- break;
- }
- }
-
- return std_ev->exit_code;
-}
-
-static const struct event_ops std_event_ops = {
- .context_init = std_event_context_init,
- .add_fd = std_event_add_fd,
- .get_fd_flags = std_event_get_fd_flags,
- .set_fd_flags = std_event_set_fd_flags,
- .add_timed = common_event_add_timed,
- .add_signal = common_event_add_signal,
- .loop_once = std_event_loop_once,
- .loop_wait = std_event_loop_wait,
-};
-
-
-bool events_standard_init(void)
-{
- return event_register_backend("standard", &std_event_ops);
-}
-