Unix SMB/CIFS implementation.
main select loop and event handling
Copyright (C) Andrew Tridgell 2003
-
- 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,
+ Copyright (C) Stefan Metzmacher 2009
+
+ ** NOTE! The following LGPL license applies to the tevent
+ ** library. This does NOT imply that all of Samba is released
+ ** under the LGPL
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 3 of the License, or (at your option) any later version.
+
+ This library 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/>.
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
/*
handler to get another event.
To setup a set of events you first need to create a event_context
- structure using the function event_context_init(); This returns a
+ structure using the function tevent_context_init(); This returns a
'struct tevent_context' that you use in all subsequent calls.
After that you can add/remove events that you are interested in
- using event_add_*() and talloc_free()
+ using tevent_add_*() and talloc_free()
- Finally, you call event_loop_wait_once() to block waiting for one of the
- events to occor or event_loop_wait() which will loop
+ Finally, you call tevent_loop_wait_once() to block waiting for one of the
+ events to occor or tevent_loop_wait() which will loop
forever.
*/
#include "replace.h"
+#include "system/filesys.h"
+#ifdef HAVE_PTHREAD
+#include "system/threads.h"
+#endif
+#define TEVENT_DEPRECATED 1
#include "tevent.h"
#include "tevent_internal.h"
#include "tevent_util.h"
+#ifdef HAVE_EVENTFD
+#include <sys/eventfd.h>
+#endif
+
+static void tevent_abort(struct tevent_context *ev, const char *reason);
-struct event_ops_list {
- struct event_ops_list *next, *prev;
+struct tevent_ops_list {
+ struct tevent_ops_list *next, *prev;
const char *name;
- const struct event_ops *ops;
+ const struct tevent_ops *ops;
};
/* list of registered event backends */
-static struct event_ops_list *event_backends = NULL;
-static char *event_default_backend = NULL;
+static struct tevent_ops_list *tevent_backends = NULL;
+static char *tevent_default_backend = NULL;
/*
register an events backend
*/
-bool event_register_backend(const char *name, const struct event_ops *ops)
+bool tevent_register_backend(const char *name, const struct tevent_ops *ops)
{
- struct event_ops_list *e;
+ struct tevent_ops_list *e;
- for (e = event_backends; e != NULL; e = e->next) {
+ for (e = tevent_backends; e != NULL; e = e->next) {
if (0 == strcmp(e->name, name)) {
/* already registered, skip it */
return true;
}
}
- e = talloc(talloc_autofree_context(), struct event_ops_list);
+ e = talloc(NULL, struct tevent_ops_list);
if (e == NULL) return false;
e->name = name;
e->ops = ops;
- DLIST_ADD(event_backends, e);
+ DLIST_ADD(tevent_backends, e);
return true;
}
/*
set the default event backend
*/
-void event_set_default_backend(const char *backend)
+void tevent_set_default_backend(const char *backend)
{
- if (event_default_backend) free(event_default_backend);
- event_default_backend = strdup(backend);
+ talloc_free(tevent_default_backend);
+ tevent_default_backend = talloc_strdup(NULL, backend);
}
/*
initialise backends if not already done
*/
-static void event_backend_init(void)
+static void tevent_backend_init(void)
{
- events_select_init();
- events_standard_init();
-#if HAVE_EVENTS_EPOLL
- events_epoll_init();
-#endif
-#if HAVE_LINUX_AIO
- events_aio_init();
+ static bool done;
+
+ if (done) {
+ return;
+ }
+
+ done = true;
+
+ tevent_select_init();
+ tevent_poll_init();
+ tevent_poll_mt_init();
+#if defined(HAVE_EPOLL)
+ tevent_epoll_init();
+#elif defined(HAVE_SOLARIS_PORTS)
+ tevent_port_init();
#endif
+
+ tevent_standard_init();
+}
+
+_PRIVATE_ const struct tevent_ops *tevent_find_ops_byname(const char *name)
+{
+ struct tevent_ops_list *e;
+
+ tevent_backend_init();
+
+ if (name == NULL) {
+ name = tevent_default_backend;
+ }
+ if (name == NULL) {
+ name = "standard";
+ }
+
+ for (e = tevent_backends; e != NULL; e = e->next) {
+ if (0 == strcmp(e->name, name)) {
+ return e->ops;
+ }
+ }
+
+ return NULL;
}
/*
list available backends
*/
-const char **event_backend_list(TALLOC_CTX *mem_ctx)
+const char **tevent_backend_list(TALLOC_CTX *mem_ctx)
{
const char **list = NULL;
- struct event_ops_list *e;
+ struct tevent_ops_list *e;
- event_backend_init();
+ tevent_backend_init();
- for (e=event_backends;e;e=e->next) {
+ for (e=tevent_backends;e;e=e->next) {
list = ev_str_list_add(list, e->name);
}
return list;
}
+static void tevent_common_wakeup_fini(struct tevent_context *ev);
+
+#ifdef HAVE_PTHREAD
+
+static pthread_mutex_t tevent_contexts_mutex = PTHREAD_MUTEX_INITIALIZER;
+static struct tevent_context *tevent_contexts = NULL;
+static pthread_once_t tevent_atfork_initialized = PTHREAD_ONCE_INIT;
+
+static void tevent_atfork_prepare(void)
+{
+ struct tevent_context *ev;
+ int ret;
+
+ ret = pthread_mutex_lock(&tevent_contexts_mutex);
+ if (ret != 0) {
+ abort();
+ }
+
+ for (ev = tevent_contexts; ev != NULL; ev = ev->next) {
+ struct tevent_threaded_context *tctx;
+
+ for (tctx = ev->threaded_contexts; tctx != NULL;
+ tctx = tctx->next) {
+ ret = pthread_mutex_lock(&tctx->event_ctx_mutex);
+ if (ret != 0) {
+ tevent_abort(ev, "pthread_mutex_lock failed");
+ }
+ }
+
+ ret = pthread_mutex_lock(&ev->scheduled_mutex);
+ if (ret != 0) {
+ tevent_abort(ev, "pthread_mutex_lock failed");
+ }
+ }
+}
+
+static void tevent_atfork_parent(void)
+{
+ struct tevent_context *ev;
+ int ret;
+
+ for (ev = DLIST_TAIL(tevent_contexts); ev != NULL;
+ ev = DLIST_PREV(ev)) {
+ struct tevent_threaded_context *tctx;
+
+ ret = pthread_mutex_unlock(&ev->scheduled_mutex);
+ if (ret != 0) {
+ tevent_abort(ev, "pthread_mutex_unlock failed");
+ }
+
+ for (tctx = DLIST_TAIL(ev->threaded_contexts); tctx != NULL;
+ tctx = DLIST_PREV(tctx)) {
+ ret = pthread_mutex_unlock(&tctx->event_ctx_mutex);
+ if (ret != 0) {
+ tevent_abort(
+ ev, "pthread_mutex_unlock failed");
+ }
+ }
+ }
+
+ ret = pthread_mutex_unlock(&tevent_contexts_mutex);
+ if (ret != 0) {
+ abort();
+ }
+}
+
+static void tevent_atfork_child(void)
+{
+ struct tevent_context *ev;
+ int ret;
+
+ for (ev = DLIST_TAIL(tevent_contexts); ev != NULL;
+ ev = DLIST_PREV(ev)) {
+ struct tevent_threaded_context *tctx;
+
+ for (tctx = DLIST_TAIL(ev->threaded_contexts); tctx != NULL;
+ tctx = DLIST_PREV(tctx)) {
+ tctx->event_ctx = NULL;
+
+ ret = pthread_mutex_unlock(&tctx->event_ctx_mutex);
+ if (ret != 0) {
+ tevent_abort(
+ ev, "pthread_mutex_unlock failed");
+ }
+ }
+
+ ev->threaded_contexts = NULL;
+
+ ret = pthread_mutex_unlock(&ev->scheduled_mutex);
+ if (ret != 0) {
+ tevent_abort(ev, "pthread_mutex_unlock failed");
+ }
+ }
+
+ ret = pthread_mutex_unlock(&tevent_contexts_mutex);
+ if (ret != 0) {
+ abort();
+ }
+}
+
+static void tevent_prep_atfork(void)
+{
+ int ret;
+
+ ret = pthread_atfork(tevent_atfork_prepare,
+ tevent_atfork_parent,
+ tevent_atfork_child);
+ if (ret != 0) {
+ abort();
+ }
+}
+
+#endif
+
+int tevent_common_context_destructor(struct tevent_context *ev)
+{
+ struct tevent_fd *fd, *fn;
+ struct tevent_timer *te, *tn;
+ struct tevent_immediate *ie, *in;
+ struct tevent_signal *se, *sn;
+
+#ifdef HAVE_PTHREAD
+ int ret;
+
+ ret = pthread_mutex_lock(&tevent_contexts_mutex);
+ if (ret != 0) {
+ abort();
+ }
+
+ DLIST_REMOVE(tevent_contexts, ev);
+
+ ret = pthread_mutex_unlock(&tevent_contexts_mutex);
+ if (ret != 0) {
+ abort();
+ }
+
+ while (ev->threaded_contexts != NULL) {
+ struct tevent_threaded_context *tctx = ev->threaded_contexts;
+
+ ret = pthread_mutex_lock(&tctx->event_ctx_mutex);
+ if (ret != 0) {
+ abort();
+ }
+
+ /*
+ * Indicate to the thread that the tevent_context is
+ * gone. The counterpart of this is in
+ * _tevent_threaded_schedule_immediate, there we read
+ * this under the threaded_context's mutex.
+ */
+
+ tctx->event_ctx = NULL;
+
+ ret = pthread_mutex_unlock(&tctx->event_ctx_mutex);
+ if (ret != 0) {
+ abort();
+ }
+
+ DLIST_REMOVE(ev->threaded_contexts, tctx);
+ }
+#endif
+
+ tevent_common_wakeup_fini(ev);
+
+ for (fd = ev->fd_events; fd; fd = fn) {
+ fn = fd->next;
+ fd->event_ctx = NULL;
+ DLIST_REMOVE(ev->fd_events, fd);
+ }
+
+ ev->last_zero_timer = NULL;
+ for (te = ev->timer_events; te; te = tn) {
+ tn = te->next;
+ te->event_ctx = NULL;
+ DLIST_REMOVE(ev->timer_events, te);
+ }
+
+ for (ie = ev->immediate_events; ie; ie = in) {
+ in = ie->next;
+ ie->event_ctx = NULL;
+ ie->cancel_fn = NULL;
+ DLIST_REMOVE(ev->immediate_events, ie);
+ }
+
+ for (se = ev->signal_events; se; se = sn) {
+ sn = se->next;
+ se->event_ctx = NULL;
+ DLIST_REMOVE(ev->signal_events, se);
+ /*
+ * This is important, Otherwise signals
+ * are handled twice in child. eg, SIGHUP.
+ * one added in parent, and another one in
+ * the child. -- BoYang
+ */
+ tevent_cleanup_pending_signal_handlers(se);
+ }
+
+ /* removing nesting hook or we get an abort when nesting is
+ * not allowed. -- SSS
+ * Note that we need to leave the allowed flag at its current
+ * value, otherwise the use in tevent_re_initialise() will
+ * leave the event context with allowed forced to false, which
+ * will break users that expect nesting to be allowed
+ */
+ ev->nesting.level = 0;
+ ev->nesting.hook_fn = NULL;
+ ev->nesting.hook_private = NULL;
+
+ return 0;
+}
+
/*
create a event_context structure for a specific implemementation.
This must be the first events call, and all subsequent calls pass
This function is for allowing third-party-applications to hook in gluecode
to their own event loop code, so that they can make async usage of our client libs
- NOTE: use event_context_init() inside of samba!
+ NOTE: use tevent_context_init() inside of samba!
*/
-static struct tevent_context *event_context_init_ops(TALLOC_CTX *mem_ctx,
- const struct event_ops *ops)
+struct tevent_context *tevent_context_init_ops(TALLOC_CTX *mem_ctx,
+ const struct tevent_ops *ops,
+ void *additional_data)
{
struct tevent_context *ev;
int ret;
ev = talloc_zero(mem_ctx, struct tevent_context);
if (!ev) return NULL;
+#ifdef HAVE_PTHREAD
+
+ ret = pthread_once(&tevent_atfork_initialized, tevent_prep_atfork);
+ if (ret != 0) {
+ talloc_free(ev);
+ return NULL;
+ }
+
+ ret = pthread_mutex_init(&ev->scheduled_mutex, NULL);
+ if (ret != 0) {
+ talloc_free(ev);
+ return NULL;
+ }
+
+ ret = pthread_mutex_lock(&tevent_contexts_mutex);
+ if (ret != 0) {
+ pthread_mutex_destroy(&ev->scheduled_mutex);
+ talloc_free(ev);
+ return NULL;
+ }
+
+ DLIST_ADD(tevent_contexts, ev);
+
+ ret = pthread_mutex_unlock(&tevent_contexts_mutex);
+ if (ret != 0) {
+ abort();
+ }
+
+#endif
+
+ talloc_set_destructor(ev, tevent_common_context_destructor);
+
ev->ops = ops;
+ ev->additional_data = additional_data;
ret = ev->ops->context_init(ev);
if (ret != 0) {
call, and all subsequent calls pass this event_context as the first
element. Event handlers also receive this as their first argument.
*/
-struct tevent_context *event_context_init_byname(TALLOC_CTX *mem_ctx, const char *name)
+struct tevent_context *tevent_context_init_byname(TALLOC_CTX *mem_ctx,
+ const char *name)
{
- struct event_ops_list *e;
-
- event_backend_init();
+ const struct tevent_ops *ops;
- if (name == NULL) {
- name = event_default_backend;
- }
- if (name == NULL) {
- name = "standard";
+ ops = tevent_find_ops_byname(name);
+ if (ops == NULL) {
+ return NULL;
}
- for (e=event_backends;e;e=e->next) {
- if (strcmp(name, e->name) == 0) {
- return event_context_init_ops(mem_ctx, e->ops);
- }
- }
- return NULL;
+ return tevent_context_init_ops(mem_ctx, ops, NULL);
}
call, and all subsequent calls pass this event_context as the first
element. Event handlers also receive this as their first argument.
*/
-struct tevent_context *event_context_init(TALLOC_CTX *mem_ctx)
+struct tevent_context *tevent_context_init(TALLOC_CTX *mem_ctx)
{
- return event_context_init_byname(mem_ctx, NULL);
+ return tevent_context_init_byname(mem_ctx, NULL);
}
/*
add a fd based event
return NULL on failure (memory allocation error)
-
- if flags contains EVENT_FD_AUTOCLOSE then the fd will be closed when
- the returned fd_event context is freed
*/
-struct tevent_fd *event_add_fd(struct tevent_context *ev, TALLOC_CTX *mem_ctx,
- int fd, uint16_t flags, event_fd_handler_t handler,
- void *private_data)
+struct tevent_fd *_tevent_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)
{
- return ev->ops->add_fd(ev, mem_ctx, fd, flags, handler, private_data);
+ return ev->ops->add_fd(ev, mem_ctx, fd, flags, handler, private_data,
+ handler_name, location);
}
/*
- add a disk aio event
+ set a close function on the fd event
*/
-struct aio_event *event_add_aio(struct tevent_context *ev,
- TALLOC_CTX *mem_ctx,
- struct iocb *iocb,
- event_aio_handler_t handler,
- void *private_data)
+void tevent_fd_set_close_fn(struct tevent_fd *fde,
+ tevent_fd_close_fn_t close_fn)
+{
+ if (!fde) return;
+ if (!fde->event_ctx) return;
+ fde->event_ctx->ops->set_fd_close_fn(fde, close_fn);
+}
+
+static void tevent_fd_auto_close_fn(struct tevent_context *ev,
+ struct tevent_fd *fde,
+ int fd,
+ void *private_data)
{
- if (ev->ops->add_aio == NULL) return NULL;
- return ev->ops->add_aio(ev, mem_ctx, iocb, handler, private_data);
+ close(fd);
+}
+
+void tevent_fd_set_auto_close(struct tevent_fd *fde)
+{
+ tevent_fd_set_close_fn(fde, tevent_fd_auto_close_fn);
}
/*
return the fd event flags
*/
-uint16_t event_get_fd_flags(struct tevent_fd *fde)
+uint16_t tevent_fd_get_flags(struct tevent_fd *fde)
{
if (!fde) return 0;
+ if (!fde->event_ctx) return 0;
return fde->event_ctx->ops->get_fd_flags(fde);
}
/*
set the fd event flags
*/
-void event_set_fd_flags(struct tevent_fd *fde, uint16_t flags)
+void tevent_fd_set_flags(struct tevent_fd *fde, uint16_t flags)
{
if (!fde) return;
+ if (!fde->event_ctx) return;
fde->event_ctx->ops->set_fd_flags(fde, flags);
}
+bool tevent_signal_support(struct tevent_context *ev)
+{
+ if (ev->ops->add_signal) {
+ return true;
+ }
+ return false;
+}
+
+static void (*tevent_abort_fn)(const char *reason);
+
+void tevent_set_abort_fn(void (*abort_fn)(const char *reason))
+{
+ tevent_abort_fn = abort_fn;
+}
+
+static void tevent_abort(struct tevent_context *ev, const char *reason)
+{
+ tevent_debug(ev, TEVENT_DEBUG_FATAL,
+ "abort: %s\n", reason);
+
+ if (!tevent_abort_fn) {
+ abort();
+ }
+
+ tevent_abort_fn(reason);
+}
+
/*
- add a timed event
+ add a timer event
return NULL on failure
*/
-struct tevent_timer *event_add_timed(struct tevent_context *ev, TALLOC_CTX *mem_ctx,
- struct timeval next_event,
- event_timed_handler_t handler,
- void *private_data)
+struct tevent_timer *_tevent_add_timer(struct tevent_context *ev,
+ TALLOC_CTX *mem_ctx,
+ struct timeval next_event,
+ tevent_timer_handler_t handler,
+ void *private_data,
+ const char *handler_name,
+ const char *location)
+{
+ return ev->ops->add_timer(ev, mem_ctx, next_event, handler, private_data,
+ handler_name, location);
+}
+
+/*
+ allocate an immediate event
+ return NULL on failure (memory allocation error)
+*/
+struct tevent_immediate *_tevent_create_immediate(TALLOC_CTX *mem_ctx,
+ const char *location)
{
- return ev->ops->add_timer(ev, mem_ctx, next_event, handler, private_data);
+ struct tevent_immediate *im;
+
+ im = talloc(mem_ctx, struct tevent_immediate);
+ if (im == NULL) return NULL;
+
+ im->prev = NULL;
+ im->next = NULL;
+ im->event_ctx = NULL;
+ im->create_location = location;
+ im->handler = NULL;
+ im->private_data = NULL;
+ im->handler_name = NULL;
+ im->schedule_location = NULL;
+ im->cancel_fn = NULL;
+ im->additional_data = NULL;
+
+ return im;
+}
+
+/*
+ schedule an immediate event
+*/
+void _tevent_schedule_immediate(struct tevent_immediate *im,
+ struct tevent_context *ev,
+ tevent_immediate_handler_t handler,
+ void *private_data,
+ const char *handler_name,
+ const char *location)
+{
+ ev->ops->schedule_immediate(im, ev, handler, private_data,
+ handler_name, location);
}
/*
return NULL on failure
*/
-struct signal_event *event_add_signal(struct tevent_context *ev, TALLOC_CTX *mem_ctx,
- int signum,
- int sa_flags,
- event_signal_handler_t handler,
- void *private_data)
+struct tevent_signal *_tevent_add_signal(struct tevent_context *ev,
+ TALLOC_CTX *mem_ctx,
+ int signum,
+ int sa_flags,
+ tevent_signal_handler_t handler,
+ void *private_data,
+ const char *handler_name,
+ const char *location)
+{
+ return ev->ops->add_signal(ev, mem_ctx, signum, sa_flags, handler, private_data,
+ handler_name, location);
+}
+
+void tevent_loop_allow_nesting(struct tevent_context *ev)
+{
+ ev->nesting.allowed = true;
+}
+
+void tevent_loop_set_nesting_hook(struct tevent_context *ev,
+ tevent_nesting_hook hook,
+ void *private_data)
{
- return ev->ops->add_signal(ev, mem_ctx, signum, sa_flags, handler, private_data);
+ if (ev->nesting.hook_fn &&
+ (ev->nesting.hook_fn != hook ||
+ ev->nesting.hook_private != private_data)) {
+ /* the way the nesting hook code is currently written
+ we cannot support two different nesting hooks at the
+ same time. */
+ tevent_abort(ev, "tevent: Violation of nesting hook rules\n");
+ }
+ ev->nesting.hook_fn = hook;
+ ev->nesting.hook_private = private_data;
+}
+
+static void tevent_abort_nesting(struct tevent_context *ev, const char *location)
+{
+ const char *reason;
+
+ reason = talloc_asprintf(NULL, "tevent_loop_once() nesting at %s",
+ location);
+ if (!reason) {
+ reason = "tevent_loop_once() nesting";
+ }
+
+ tevent_abort(ev, reason);
}
/*
do a single event loop using the events defined in ev
*/
-int event_loop_once(struct tevent_context *ev)
+int _tevent_loop_once(struct tevent_context *ev, const char *location)
{
- return ev->ops->loop_once(ev);
+ int ret;
+ void *nesting_stack_ptr = NULL;
+
+ ev->nesting.level++;
+
+ if (ev->nesting.level > 1) {
+ if (!ev->nesting.allowed) {
+ tevent_abort_nesting(ev, location);
+ errno = ELOOP;
+ return -1;
+ }
+ }
+ if (ev->nesting.level > 0) {
+ if (ev->nesting.hook_fn) {
+ int ret2;
+ ret2 = ev->nesting.hook_fn(ev,
+ ev->nesting.hook_private,
+ ev->nesting.level,
+ true,
+ (void *)&nesting_stack_ptr,
+ location);
+ if (ret2 != 0) {
+ ret = ret2;
+ goto done;
+ }
+ }
+ }
+
+ tevent_trace_point_callback(ev, TEVENT_TRACE_BEFORE_LOOP_ONCE);
+ ret = ev->ops->loop_once(ev, location);
+ tevent_trace_point_callback(ev, TEVENT_TRACE_AFTER_LOOP_ONCE);
+
+ if (ev->nesting.level > 0) {
+ if (ev->nesting.hook_fn) {
+ int ret2;
+ ret2 = ev->nesting.hook_fn(ev,
+ ev->nesting.hook_private,
+ ev->nesting.level,
+ false,
+ (void *)&nesting_stack_ptr,
+ location);
+ if (ret2 != 0) {
+ ret = ret2;
+ goto done;
+ }
+ }
+ }
+
+done:
+ ev->nesting.level--;
+ return ret;
+}
+
+/*
+ this is a performance optimization for the samba4 nested event loop problems
+*/
+int _tevent_loop_until(struct tevent_context *ev,
+ bool (*finished)(void *private_data),
+ void *private_data,
+ const char *location)
+{
+ int ret = 0;
+ void *nesting_stack_ptr = NULL;
+
+ ev->nesting.level++;
+
+ if (ev->nesting.level > 1) {
+ if (!ev->nesting.allowed) {
+ tevent_abort_nesting(ev, location);
+ errno = ELOOP;
+ return -1;
+ }
+ }
+ if (ev->nesting.level > 0) {
+ if (ev->nesting.hook_fn) {
+ int ret2;
+ ret2 = ev->nesting.hook_fn(ev,
+ ev->nesting.hook_private,
+ ev->nesting.level,
+ true,
+ (void *)&nesting_stack_ptr,
+ location);
+ if (ret2 != 0) {
+ ret = ret2;
+ goto done;
+ }
+ }
+ }
+
+ while (!finished(private_data)) {
+ tevent_trace_point_callback(ev, TEVENT_TRACE_BEFORE_LOOP_ONCE);
+ ret = ev->ops->loop_once(ev, location);
+ tevent_trace_point_callback(ev, TEVENT_TRACE_AFTER_LOOP_ONCE);
+ if (ret != 0) {
+ break;
+ }
+ }
+
+ if (ev->nesting.level > 0) {
+ if (ev->nesting.hook_fn) {
+ int ret2;
+ ret2 = ev->nesting.hook_fn(ev,
+ ev->nesting.hook_private,
+ ev->nesting.level,
+ false,
+ (void *)&nesting_stack_ptr,
+ location);
+ if (ret2 != 0) {
+ ret = ret2;
+ goto done;
+ }
+ }
+ }
+
+done:
+ ev->nesting.level--;
+ return ret;
+}
+
+bool tevent_common_have_events(struct tevent_context *ev)
+{
+ if (ev->fd_events != NULL) {
+ if (ev->fd_events != ev->wakeup_fde) {
+ return true;
+ }
+ if (ev->fd_events->next != NULL) {
+ return true;
+ }
+
+ /*
+ * At this point we just have the wakeup pipe event as
+ * the only fd_event. That one does not count as a
+ * regular event, so look at the other event types.
+ */
+ }
+
+ return ((ev->timer_events != NULL) ||
+ (ev->immediate_events != NULL) ||
+ (ev->signal_events != NULL));
+}
+
+/*
+ return on failure or (with 0) if all fd events are removed
+*/
+int tevent_common_loop_wait(struct tevent_context *ev,
+ const char *location)
+{
+ /*
+ * loop as long as we have events pending
+ */
+ while (tevent_common_have_events(ev)) {
+ int ret;
+ ret = _tevent_loop_once(ev, location);
+ if (ret != 0) {
+ tevent_debug(ev, TEVENT_DEBUG_FATAL,
+ "_tevent_loop_once() failed: %d - %s\n",
+ ret, strerror(errno));
+ return ret;
+ }
+ }
+
+ tevent_debug(ev, TEVENT_DEBUG_WARNING,
+ "tevent_common_loop_wait() out of events\n");
+ return 0;
}
/*
return on failure or (with 0) if all fd events are removed
*/
-int event_loop_wait(struct tevent_context *ev)
+int _tevent_loop_wait(struct tevent_context *ev, const char *location)
{
- return ev->ops->loop_wait(ev);
+ return ev->ops->loop_wait(ev, location);
}
+
/*
- find an event context that is a parent of the given memory context,
- or create a new event context as a child of the given context if
- none is found
+ re-initialise a tevent context. This leaves you with the same
+ event context, but all events are wiped and the structure is
+ re-initialised. This is most useful after a fork()
- This should be used in preference to event_context_init() in places
- where you would prefer to use the existing event context if possible
- (which is most situations)
+ zero is returned on success, non-zero on failure
*/
-struct tevent_context *event_context_find(TALLOC_CTX *mem_ctx)
+int tevent_re_initialise(struct tevent_context *ev)
{
- struct tevent_context *ev = talloc_find_parent_bytype(mem_ctx, struct tevent_context);
- if (ev == NULL) {
- ev = event_context_init(mem_ctx);
+ tevent_common_context_destructor(ev);
+
+ return ev->ops->context_init(ev);
+}
+
+static void wakeup_pipe_handler(struct tevent_context *ev,
+ struct tevent_fd *fde,
+ uint16_t flags, void *_private)
+{
+ ssize_t ret;
+
+ do {
+ /*
+ * This is the boilerplate for eventfd, but it works
+ * for pipes too. And as we don't care about the data
+ * we read, we're fine.
+ */
+ uint64_t val;
+ ret = read(fde->fd, &val, sizeof(val));
+ } while (ret == -1 && errno == EINTR);
+}
+
+/*
+ * Initialize the wakeup pipe and pipe fde
+ */
+
+int tevent_common_wakeup_init(struct tevent_context *ev)
+{
+ int ret, read_fd;
+
+ if (ev->wakeup_fde != NULL) {
+ return 0;
}
- return ev;
+
+#ifdef HAVE_EVENTFD
+ ret = eventfd(0, EFD_NONBLOCK);
+ if (ret == -1) {
+ return errno;
+ }
+ read_fd = ev->wakeup_fd = ret;
+#else
+ {
+ int pipe_fds[2];
+ ret = pipe(pipe_fds);
+ if (ret == -1) {
+ return errno;
+ }
+ ev->wakeup_fd = pipe_fds[1];
+ ev->wakeup_read_fd = pipe_fds[0];
+
+ ev_set_blocking(ev->wakeup_fd, false);
+ ev_set_blocking(ev->wakeup_read_fd, false);
+
+ read_fd = ev->wakeup_read_fd;
+ }
+#endif
+
+ ev->wakeup_fde = tevent_add_fd(ev, ev, read_fd, TEVENT_FD_READ,
+ wakeup_pipe_handler, NULL);
+ if (ev->wakeup_fde == NULL) {
+ close(ev->wakeup_fd);
+#ifndef HAVE_EVENTFD
+ close(ev->wakeup_read_fd);
+#endif
+ return ENOMEM;
+ }
+
+ return 0;
+}
+
+int tevent_common_wakeup_fd(int fd)
+{
+ ssize_t ret;
+
+ do {
+#ifdef HAVE_EVENTFD
+ uint64_t val = 1;
+ ret = write(fd, &val, sizeof(val));
+#else
+ char c = '\0';
+ ret = write(fd, &c, 1);
+#endif
+ } while ((ret == -1) && (errno == EINTR));
+
+ return 0;
+}
+
+int tevent_common_wakeup(struct tevent_context *ev)
+{
+ if (ev->wakeup_fde == NULL) {
+ return ENOTCONN;
+ }
+
+ return tevent_common_wakeup_fd(ev->wakeup_fd);
+}
+
+static void tevent_common_wakeup_fini(struct tevent_context *ev)
+{
+ if (ev->wakeup_fde == NULL) {
+ return;
+ }
+
+ TALLOC_FREE(ev->wakeup_fde);
+
+ close(ev->wakeup_fd);
+#ifndef HAVE_EVENTFD
+ close(ev->wakeup_read_fd);
+#endif
}
git.samba.org / sfrench / samba-autobuild / .git / blobdiff