*/
#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 tevent_ops_list {
struct tevent_ops_list *next, *prev;
}
}
- e = talloc(talloc_autofree_context(), struct tevent_ops_list);
+ e = talloc(NULL, struct tevent_ops_list);
if (e == NULL) return false;
e->name = name;
void tevent_set_default_backend(const char *backend)
{
talloc_free(tevent_default_backend);
- tevent_default_backend = talloc_strdup(talloc_autofree_context(),
- backend);
+ tevent_default_backend = talloc_strdup(NULL, backend);
}
/*
*/
static void tevent_backend_init(void)
{
+ static bool done;
+
+ if (done) {
+ return;
+ }
+
+ done = true;
+
tevent_select_init();
- tevent_standard_init();
-#ifdef HAVE_EPOLL
+ 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";
+ name = "poll";
+ }
+
+ for (e = tevent_backends; e != NULL; e = e->next) {
+ if (0 == strcmp(e->name, name)) {
+ return e->ops;
+ }
+ }
+
+ return NULL;
}
/*
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) {
+ 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)) {
+ 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_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 = ev->threaded_contexts; tctx != NULL;
+ tctx = tctx->next) {
+ tctx->event_ctx = NULL;
+ }
+
+ 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;
- if (ev->pipe_fde) {
- talloc_free(ev->pipe_fde);
- ev->pipe_fde = NULL;
+#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();
+ }
+#endif
+
+ if (ev->threaded_contexts != NULL) {
+ /*
+ * Threaded contexts are indicators that threads are
+ * about to send us immediates via
+ * tevent_threaded_schedule_immediate. The caller
+ * needs to make sure that the tevent context lives
+ * long enough to receive immediates from all threads.
+ */
+ tevent_abort(ev, "threaded contexts exist");
}
+ 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;
}
NOTE: use tevent_context_init() inside of samba!
*/
-static struct tevent_context *tevent_context_init_ops(TALLOC_CTX *mem_ctx,
- const struct tevent_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) {
struct tevent_context *tevent_context_init_byname(TALLOC_CTX *mem_ctx,
const char *name)
{
- struct tevent_ops_list *e;
-
- tevent_backend_init();
+ const struct tevent_ops *ops;
- if (name == NULL) {
- name = tevent_default_backend;
- }
- if (name == NULL) {
- name = "standard";
+ ops = tevent_find_ops_byname(name);
+ if (ops == NULL) {
+ return NULL;
}
- for (e=tevent_backends;e;e=e->next) {
- if (strcmp(name, e->name) == 0) {
- return tevent_context_init_ops(mem_ctx, e->ops);
- }
- }
- return NULL;
+ return tevent_context_init_ops(mem_ctx, ops, NULL);
}
/*
add a fd based event
return NULL on failure (memory allocation error)
-
- if flags contains TEVENT_FD_AUTOCLOSE then the fd will be closed when
- the returned fd_event context is freed
*/
struct tevent_fd *_tevent_add_fd(struct tevent_context *ev,
TALLOC_CTX *mem_ctx,
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)
+{
+ 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);
+}
+
/*
add a signal event
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)
+{
+ 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 tevent_loop_once(struct tevent_context *ev)
+int _tevent_loop_once(struct tevent_context *ev, const char *location)
+{
+ 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)
{
- return ev->ops->loop_once(ev);
+ /*
+ * 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 tevent_loop_wait(struct tevent_context *ev)
+int _tevent_loop_wait(struct tevent_context *ev, const char *location)
+{
+ return ev->ops->loop_wait(ev, location);
+}
+
+
+/*
+ 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()
+
+ zero is returned on success, non-zero on failure
+*/
+int tevent_re_initialise(struct tevent_context *ev)
+{
+ 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;
+
+ if (ev->wakeup_fde != NULL) {
+ return 0;
+ }
+
+#ifdef HAVE_EVENTFD
+ ret = eventfd(0, EFD_NONBLOCK);
+ if (ret == -1) {
+ return errno;
+ }
+ ev->wakeup_fd = ret;
+#else
+ {
+ int pipe_fds[2];
+ ret = pipe(pipe_fds);
+ if (ret == -1) {
+ return errno;
+ }
+ ev->wakeup_fd = pipe_fds[0];
+ ev->wakeup_write_fd = pipe_fds[1];
+
+ ev_set_blocking(ev->wakeup_fd, false);
+ ev_set_blocking(ev->wakeup_write_fd, false);
+ }
+#endif
+
+ ev->wakeup_fde = tevent_add_fd(ev, ev, ev->wakeup_fd,
+ TEVENT_FD_READ,
+ wakeup_pipe_handler, NULL);
+ if (ev->wakeup_fde == NULL) {
+ close(ev->wakeup_fd);
+#ifndef HAVE_EVENTFD
+ close(ev->wakeup_write_fd);
+#endif
+ return ENOMEM;
+ }
+
+ return 0;
+}
+
+int tevent_common_wakeup(struct tevent_context *ev)
+{
+ ssize_t ret;
+
+ if (ev->wakeup_fde == NULL) {
+ return ENOTCONN;
+ }
+
+ do {
+#ifdef HAVE_EVENTFD
+ uint64_t val = 1;
+ ret = write(ev->wakeup_fd, &val, sizeof(val));
+#else
+ char c = '\0';
+ ret = write(ev->wakeup_write_fd, &c, 1);
+#endif
+ } while ((ret == -1) && (errno == EINTR));
+
+ return 0;
+}
+
+static void tevent_common_wakeup_fini(struct tevent_context *ev)
{
- return ev->ops->loop_wait(ev);
+ if (ev->wakeup_fde == NULL) {
+ return;
+ }
+
+ TALLOC_FREE(ev->wakeup_fde);
+
+ close(ev->wakeup_fd);
+#ifndef HAVE_EVENTFD
+ close(ev->wakeup_write_fd);
+#endif
}