Adding upstream version 2:4.20.0+dfsg.upstream/2%4.20.0+dfsg

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 881 insertions, 0 deletions

diff --git a/source3/lib/tevent_glib_glue.c b/source3/lib/tevent_glib_glue.c
new file mode 100644
index 0000000..3be08fc
--- /dev/null
+++ b/source3/lib/tevent_glib_glue.c
@@ -0,0 +1,881 @@
+/*
+   Unix SMB/CIFS implementation.
+   Integration of a glib g_main_context into a tevent_context
+   Copyright (C) Stefan Metzmacher 2016
+   Copyright (C) Ralph Boehme 2016
+
+     ** 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
+   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/>.
+*/
+
+#include "replace.h"
+#include "system/filesys.h"
+#include "lib/util/debug.h"
+#include "lib/util/select.h"
+#include <tevent.h>
+
+#undef DBGC_CLASS
+#define DBGC_CLASS DBGC_TEVENT
+
+#ifdef HAVE_GLIB
+#include <glib.h>
+#include "tevent_glib_glue.h"
+
+struct fd_map {
+	struct tevent_glib_glue *glue;
+	int fd;
+	struct tevent_fd *fd_event;
+};
+
+struct tevent_glib_glue {
+	/*
+	 * The tevent context we're feeding.
+	 */
+	struct tevent_context *ev;
+
+	/*
+	 * The glib gmain context we're polling and whether we're currently
+	 * owning it by virtue of g_main_context_acquire().
+	 */
+	GMainContext *gmain_ctx;
+	bool gmain_owner;
+
+	/*
+	 * Set by samba_tevent_glib_glue_quit().
+	 */
+	bool quit;
+
+	/*
+	 * tevent trace callback and data we got from tevent_get_trace_callback()
+	 * before installing our own trace callback.
+	 */
+	tevent_trace_callback_t prev_tevent_trace_cb;
+	void *prev_tevent_trace_data;
+
+	/*
+	 * Don't call tevent_glib_prepare() in the tevent tracepoint handler if
+	 * explicitly told so. This is an optimisation for the case that glib
+	 * event sources are created from glib event callbacks.
+	 */
+	bool skip_glib_refresh;
+
+	/*
+	 * Used when acquiring the glib gmain context failed.
+	 */
+	struct tevent_timer *acquire_retry_timer;
+
+	/*
+	 * glib gmain context timeout and priority for the current event look
+	 * iteration. gtimeout is translated to a tevent timer event, unless it
+	 * is 0 which signals some event source is pending. In that case we
+	 * dispatch an immediate event. gpriority is ignored by us, just passed
+	 * to the glib relevant functions.
+	 */
+	gint gtimeout;
+	gint gpriority;
+	struct tevent_timer *timer;
+	struct tevent_immediate *im;
+	bool scheduled_im;
+
+	/*
+	 * glib gmain context fds returned from g_main_context_query(). These
+	 * get translated to tevent fd events.
+	 */
+	GPollFD *gpollfds;
+	gint num_gpollfds;
+
+	/*
+	 * A copy of gpollfds and num_gpollfds from the previous event loop
+	 * iteration, used to detect changes in the set of fds.
+	 */
+	GPollFD *prev_gpollfds;
+	gint num_prev_gpollfds;
+
+	/*
+	 * An array of pointers to fd_map's. The fd_map'd contain the tevent
+	 * event fd as well as a pointer to the corresponding glib GPollFD.
+	 */
+	struct fd_map **fd_map;
+	size_t num_maps;
+};
+
+static bool tevent_glib_prepare(struct tevent_glib_glue *glue);
+static bool tevent_glib_process(struct tevent_glib_glue *glue);
+static bool tevent_glib_glue_reinit(struct tevent_glib_glue *glue);
+static void tevent_glib_fd_handler(struct tevent_context *ev,
+				   struct tevent_fd *fde,
+				   uint16_t flags,
+				   void *private_data);
+
+typedef int (*gfds_cmp_cb)(const void *fd1, const void *fd2);
+typedef bool (*gfds_found_cb)(struct tevent_glib_glue *glue,
+			      const GPollFD *new,
+			      const GPollFD *old);
+typedef bool (*gfds_new_cb)(struct tevent_glib_glue *glue,
+			    const GPollFD *fd);
+typedef bool (*gfds_removed_cb)(struct tevent_glib_glue *glue,
+				const GPollFD *fd);
+
+/**
+ * Compare two sorted GPollFD arrays
+ *
+ * For every element that exists in gfds and prev_gfds found_fn() is called.
+ * For every element in gfds but not in prev_gfds, new_fn() is called.
+ * For every element in prev_gfds but not in gfds removed_fn() is called.
+ **/
+static bool cmp_gfds(struct tevent_glib_glue *glue,
+		     GPollFD *gfds,
+		     GPollFD *prev_gfds,
+		     size_t num_gfds,
+		     size_t num_prev_gfds,
+		     gfds_cmp_cb cmp_cb,
+		     gfds_found_cb found_cb,
+		     gfds_new_cb new_cb,
+		     gfds_removed_cb removed_cb)
+{
+	bool ok;
+	size_t i = 0, j = 0;
+	int cmp;
+
+	while (i < num_gfds && j < num_prev_gfds) {
+		cmp = cmp_cb(&gfds[i], &prev_gfds[j]);
+		if (cmp == 0) {
+			ok = found_cb(glue, &gfds[i], &prev_gfds[j]);
+			if (!ok) {
+				return false;
+			}
+			i++;
+			j++;
+		} else if (cmp < 0) {
+			ok = new_cb(glue, &gfds[i]);
+			if (!ok) {
+				return false;
+			}
+			i++;
+		} else {
+			ok = removed_cb(glue, &prev_gfds[j]);
+			if (!ok) {
+				return false;
+			}
+			j++;
+		}
+	}
+
+	while (i < num_gfds) {
+		ok = new_cb(glue, &gfds[i++]);
+		if (!ok) {
+			return false;
+		}
+	}
+
+	while (j < num_prev_gfds) {
+		ok = removed_cb(glue, &prev_gfds[j++]);
+		if (!ok) {
+			return false;
+		}
+	}
+
+	return true;
+}
+
+static int glib_fd_cmp_func(const void *p1, const void *p2)
+{
+	const GPollFD *lhs = p1;
+	const GPollFD *rhs = p2;
+
+	if (lhs->fd < rhs->fd) {
+		return -1;
+	} else if (lhs->fd > rhs->fd) {
+		return 1;
+	}
+
+	return 0;
+}
+
+/*
+ * We already have a tevent fd event for the glib GPollFD, but we may have to
+ * update flags.
+ */
+static bool match_gfd_cb(struct tevent_glib_glue *glue,
+			 const GPollFD *new_gfd,
+			 const GPollFD *old_gfd)
+{
+	size_t i;
+	struct fd_map *fd_map = NULL;
+	struct tevent_fd *fd_event = NULL;
+
+	if (new_gfd->events == old_gfd->events) {
+		return true;
+	}
+
+	for (i = 0; i < glue->num_maps; i++) {
+		if (glue->fd_map[i]->fd == new_gfd->fd) {
+			break;
+		}
+	}
+
+	if (i == glue->num_maps) {
+		DBG_ERR("match_gfd_cb: glib fd %d not in map\n", new_gfd->fd);
+		return false;
+	}
+
+	fd_map = glue->fd_map[i];
+	if (fd_map == NULL) {
+		DBG_ERR("fd_map for fd %d is NULL\n", new_gfd->fd);
+		return false;
+	}
+
+	fd_event = fd_map->fd_event;
+	if (fd_event == NULL) {
+		DBG_ERR("fd_event for fd %d is NULL\n", new_gfd->fd);
+		return false;
+	}
+
+	tevent_fd_set_flags(fd_event, 0);
+
+	if (new_gfd->events & (G_IO_IN | G_IO_HUP | G_IO_ERR)) {
+		TEVENT_FD_READABLE(fd_event);
+	}
+	if (new_gfd->events & G_IO_OUT) {
+		TEVENT_FD_WRITEABLE(fd_event);
+	}
+
+	return true;
+}
+
+static bool new_gfd_cb(struct tevent_glib_glue *glue, const GPollFD *gfd)
+{
+	struct tevent_fd *fd_event = NULL;
+	struct fd_map *fd_map = NULL;
+	uint16_t events = 0;
+	bool revent;
+	bool wevent;
+
+	revent = (gfd->events & (G_IO_IN | G_IO_HUP | G_IO_ERR));
+	wevent = (gfd->events & G_IO_OUT);
+	if (revent) {
+		events |= TEVENT_FD_READ;
+	}
+	if (wevent) {
+		events |= TEVENT_FD_WRITE;
+	}
+
+	glue->fd_map = talloc_realloc(glue,
+				      glue->fd_map,
+				      struct fd_map *,
+				      glue->num_maps + 1);
+	if (glue->fd_map == NULL) {
+		DBG_ERR("talloc_realloc failed\n");
+		return false;
+	}
+	fd_map = talloc_zero(glue->fd_map, struct fd_map);
+	if (fd_map == NULL) {
+		DBG_ERR("talloc_realloc failed\n");
+		return false;
+	}
+	glue->fd_map[glue->num_maps] = fd_map;
+	glue->num_maps++;
+
+	fd_event = tevent_add_fd(glue->ev,
+				 glue->fd_map,
+				 gfd->fd,
+				 events,
+				 tevent_glib_fd_handler,
+				 fd_map);
+	if (fd_event == NULL) {
+		DBG_ERR("tevent_add_fd failed\n");
+		return false;
+	}
+
+	*fd_map = (struct fd_map) {
+		.glue = glue,
+		.fd = gfd->fd,
+		.fd_event = fd_event,
+	};
+
+	DBG_DEBUG("added tevent_fd for glib fd %d\n", gfd->fd);
+
+	return true;
+}
+
+static bool remove_gfd_cb(struct tevent_glib_glue *glue, const GPollFD *gfd)
+{
+	size_t i;
+
+	for (i = 0; i < glue->num_maps; i++) {
+		if (glue->fd_map[i]->fd == gfd->fd) {
+			break;
+		}
+	}
+
+	if (i == glue->num_maps) {
+		DBG_ERR("remove_gfd_cb: glib fd %d not in map\n", gfd->fd);
+		return false;
+	}
+
+	TALLOC_FREE(glue->fd_map[i]->fd_event);
+	TALLOC_FREE(glue->fd_map[i]);
+
+	if (i + 1 < glue->num_maps) {
+		memmove(&glue->fd_map[i],
+			&glue->fd_map[i+1],
+			(glue->num_maps - (i + 1)) * sizeof(struct fd_map *));
+	}
+
+	glue->fd_map = talloc_realloc(glue,
+				      glue->fd_map,
+				      struct fd_map *,
+				      glue->num_maps - 1);
+	if (glue->num_maps > 0 && glue->fd_map == NULL) {
+		DBG_ERR("talloc_realloc failed\n");
+		return false;
+	}
+	glue->num_maps--;
+
+	return true;
+}
+
+static short gpoll_to_poll_event(gushort gevent)
+{
+	short pevent = 0;
+
+	if (gevent & G_IO_IN) {
+		pevent |= POLLIN;
+	}
+	if (gevent & G_IO_OUT) {
+		pevent |= POLLOUT;
+	}
+	if (gevent & G_IO_HUP) {
+		pevent |= POLLHUP;
+	}
+	if (gevent & G_IO_ERR) {
+		pevent |= POLLERR;
+	}
+
+	return pevent;
+}
+
+static gushort poll_to_gpoll_event(short pevent)
+{
+	gushort gevent = 0;
+
+	if (pevent & POLLIN) {
+		gevent |= G_IO_IN;
+	}
+	if (pevent & POLLOUT) {
+		gevent |= G_IO_OUT;
+	}
+	if (pevent & POLLHUP) {
+		gevent |= G_IO_HUP;
+	}
+	if (pevent & POLLERR) {
+		gevent |= G_IO_ERR;
+	}
+
+	return gevent;
+}
+
+static void tevent_glib_fd_handler(struct tevent_context *ev,
+				   struct tevent_fd *fde,
+				   uint16_t flags,
+				   void *private_data)
+{
+	struct fd_map *fd_map = talloc_get_type_abort(
+		private_data, struct fd_map);
+	struct tevent_glib_glue *glue = NULL;
+	GPollFD *gpollfd = NULL;
+	struct pollfd fd;
+	int ret;
+	int i;
+
+	glue = fd_map->glue;
+
+	for (i = 0; i < glue->num_gpollfds; i++) {
+		if (glue->gpollfds[i].fd != fd_map->fd) {
+			continue;
+		}
+		gpollfd = &glue->gpollfds[i];
+		break;
+	}
+	if (gpollfd == NULL) {
+		DBG_ERR("No gpollfd for fd_map [%p] fd [%d]\n",
+			fd_map, fd_map->fd);
+		return;
+	}
+	/*
+	 * We have to poll() the fd to get the correct fd event for glib. tevent
+	 * only tells us about readable/writable in flags, but we need the full
+	 * glory for glib.
+	 */
+
+	fd = (struct pollfd) {
+		.fd = gpollfd->fd,
+		.events = gpoll_to_poll_event(gpollfd->events),
+	};
+
+	ret = sys_poll_intr(&fd, 1, 0);
+	if (ret == -1) {
+		DBG_ERR("poll: %s\n", strerror(errno));
+		return;
+	}
+	if (ret == 0) {
+		return;
+	}
+
+	gpollfd->revents = poll_to_gpoll_event(fd.revents);
+
+	tevent_glib_process(glue);
+	return;
+}
+
+static void tevent_glib_timer_handler(struct tevent_context *ev,
+				      struct tevent_timer *te,
+				      struct timeval current_time,
+				      void *private_data)
+{
+	struct tevent_glib_glue *glue = talloc_get_type_abort(
+		private_data, struct tevent_glib_glue);
+
+	glue->timer = NULL;
+	tevent_glib_process(glue);
+	return;
+}
+
+static void tevent_glib_im_handler(struct tevent_context *ev,
+				   struct tevent_immediate *im,
+				   void *private_data)
+{
+	struct tevent_glib_glue *glue = talloc_get_type_abort(
+		private_data, struct tevent_glib_glue);
+
+	glue->scheduled_im = false;
+	tevent_glib_process(glue);
+	return;
+}
+
+static bool save_current_fdset(struct tevent_glib_glue *glue)
+{
+	/*
+	 * Save old glib fds. We only grow the prev array.
+	 */
+
+	if (glue->num_prev_gpollfds < glue->num_gpollfds) {
+		glue->prev_gpollfds = talloc_realloc(glue,
+						     glue->prev_gpollfds,
+						     GPollFD,
+						     glue->num_gpollfds);
+		if (glue->prev_gpollfds == NULL) {
+			DBG_ERR("talloc_realloc failed\n");
+			return false;
+		}
+	}
+	glue->num_prev_gpollfds = glue->num_gpollfds;
+	if (glue->num_gpollfds > 0) {
+		memcpy(glue->prev_gpollfds, glue->gpollfds,
+		       sizeof(GPollFD) * glue->num_gpollfds);
+		memset(glue->gpollfds, 0, sizeof(GPollFD) * glue->num_gpollfds);
+	}
+
+	return true;
+}
+
+static bool get_glib_fds_and_timeout(struct tevent_glib_glue *glue)
+{
+	bool ok;
+	gint num_fds;
+
+	ok = save_current_fdset(glue);
+	if (!ok) {
+		return false;
+	}
+
+	while (true) {
+		num_fds = g_main_context_query(glue->gmain_ctx,
+					       glue->gpriority,
+					       &glue->gtimeout,
+					       glue->gpollfds,
+					       glue->num_gpollfds);
+		if (num_fds == glue->num_gpollfds) {
+			break;
+		}
+		glue->gpollfds = talloc_realloc(glue,
+						glue->gpollfds,
+						GPollFD,
+						num_fds);
+		if (num_fds > 0 && glue->gpollfds == NULL) {
+			DBG_ERR("talloc_realloc failed\n");
+			return false;
+		}
+		glue->num_gpollfds = num_fds;
+	};
+
+	if (glue->num_gpollfds > 0) {
+		qsort(glue->gpollfds,
+		      num_fds,
+		      sizeof(GPollFD),
+		      glib_fd_cmp_func);
+	}
+
+	DBG_DEBUG("num fds: %d, timeout: %d ms\n",
+		  num_fds, glue->gtimeout);
+
+	return true;
+}
+
+static bool tevent_glib_update_events(struct tevent_glib_glue *glue)
+{
+	struct timeval tv;
+	bool ok;
+
+	ok = cmp_gfds(glue,
+		      glue->gpollfds,
+		      glue->prev_gpollfds,
+		      glue->num_gpollfds,
+		      glue->num_prev_gpollfds,
+		      glib_fd_cmp_func,
+		      match_gfd_cb,
+		      new_gfd_cb,
+		      remove_gfd_cb);
+	if (!ok) {
+		return false;
+	}
+
+	TALLOC_FREE(glue->timer);
+
+	if (glue->gtimeout == -1) {
+		return true;
+	}
+
+	if (glue->gtimeout == 0) {
+		/*
+		 * glue->gtimeout is 0 if g_main_context_query() returned
+		 * timeout=0. That means there are pending events ready to be
+		 * dispatched. We only want to run one event handler per loop
+		 * iteration, so we schedule an immediate event to run it in the
+		 * next iteration.
+		 */
+		if (glue->scheduled_im) {
+			return true;
+		}
+		tevent_schedule_immediate(glue->im,
+					  glue->ev,
+					  tevent_glib_im_handler,
+					  glue);
+		glue->scheduled_im = true;
+		return true;
+	}
+
+	tv = tevent_timeval_current_ofs(glue->gtimeout / 1000,
+					(glue->gtimeout % 1000) * 1000);
+
+	glue->timer = tevent_add_timer(glue->ev,
+				       glue,
+				       tv,
+				       tevent_glib_timer_handler,
+				       glue);
+	if (glue->timer == NULL) {
+		DBG_ERR("tevent_add_timer failed\n");
+		return false;
+	}
+
+	return true;
+}
+
+static void tevent_glib_retry_timer(struct tevent_context *ev,
+				    struct tevent_timer *te,
+				    struct timeval current_time,
+				    void *private_data)
+{
+	struct tevent_glib_glue *glue = talloc_get_type_abort(
+		private_data, struct tevent_glib_glue);
+
+	glue->acquire_retry_timer = NULL;
+	(void)tevent_glib_prepare(glue);
+}
+
+/**
+ * Fetch glib event sources and add them to tevent
+ *
+ * Fetch glib event sources and attach corresponding tevent events to our tevent
+ * context. get_glib_fds_and_timeout() gets the relevant glib event sources: the
+ * set of active fds and the next timer. tevent_glib_update_events() then
+ * translates those to tevent and creates tevent events.
+ *
+ * When called, the thread must NOT be the owner to the glib main
+ * context. tevent_glib_prepare() is either the first function when the
+ * tevent_glib_glue is created, or after tevent_glib_process() has been called
+ * to process pending event, which will have ceased ownership.
+ **/
+static bool tevent_glib_prepare(struct tevent_glib_glue *glue)
+{
+	bool ok;
+	gboolean gok;
+
+	if (glue->quit) {
+		/* Set via samba_tevent_glib_glue_quit() */
+		return true;
+	}
+
+	if (glue->acquire_retry_timer != NULL) {
+		/*
+		 * We're still waiting on the below g_main_context_acquire() to
+		 * succeed, just return.
+		 */
+		return true;
+	}
+
+	if (glue->gmain_owner) {
+		g_main_context_release(glue->gmain_ctx);
+		glue->gmain_owner = false;
+	}
+
+	gok = g_main_context_acquire(glue->gmain_ctx);
+	if (!gok) {
+		DBG_ERR("couldn't acquire g_main_context\n");
+
+		/*
+		 * Ensure no tevent event fires while we're not the gmain
+		 * context owner. The event handler would call
+		 * tevent_glib_process() and that expects being the owner of the
+		 * context.
+		 */
+		ok = tevent_glib_glue_reinit(glue);
+		if (!ok) {
+			DBG_ERR("tevent_glib_glue_reinit failed\n");
+			samba_tevent_glib_glue_quit(glue);
+			return false;
+		}
+
+		glue->acquire_retry_timer = tevent_add_timer(
+			glue->ev,
+			glue,
+			tevent_timeval_current_ofs(0, 1000),
+			tevent_glib_retry_timer,
+			glue);
+		if (glue->acquire_retry_timer == NULL) {
+			DBG_ERR("tevent_add_timer failed\n");
+			samba_tevent_glib_glue_quit(glue);
+			return false;
+		}
+		return true;
+	}
+	glue->gmain_owner = true;
+
+	/*
+	 * Discard "ready" return value from g_main_context_prepare(). We don't
+	 * want to dispatch events here, that's only done in from the tevent loop.
+	 */
+	(void)g_main_context_prepare(glue->gmain_ctx, &glue->gpriority);
+
+	ok = get_glib_fds_and_timeout(glue);
+	if (!ok) {
+		DBG_ERR("get_glib_fds_and_timeout failed\n");
+		samba_tevent_glib_glue_quit(glue);
+		return false;
+	}
+
+	ok = tevent_glib_update_events(glue);
+	if (!ok) {
+		DBG_ERR("tevent_glib_update_events failed\n");
+		samba_tevent_glib_glue_quit(glue);
+		return false;
+	}
+
+	return true;
+}
+
+/**
+ * Process pending glib events
+ *
+ * tevent_glib_process() gets called to process pending glib events via
+ * g_main_context_check() and then g_main_context_dispatch().
+ *
+ * After pending event handlers are dispatched, we rearm the glib glue event
+ * handlers in tevent by calling tevent_glib_prepare().
+ *
+ * When tevent_glib_process() is called the thread must own the glib
+ * gmain_ctx. That is achieved by tevent_glib_prepare() being the only function
+ * that acquires context ownership.
+ *
+ * To give other threads that are blocked on g_main_context_acquire(gmain_ctx) a
+ * chance to acquire context ownership (eg needed to attach event sources), we
+ * release context ownership before calling tevent_glib_prepare() which will
+ * acquire it again.
+ */
+static bool tevent_glib_process(struct tevent_glib_glue *glue)
+{
+	bool ok;
+
+	DBG_DEBUG("tevent_glib_process\n");
+
+	/*
+	 * Ignore the "sources_ready" return from g_main_context_check(). glib
+	 * itself also ignores it in g_main_context_iterate(). In theory only
+	 * calling g_main_context_dispatch() if g_main_context_check() returns
+	 * true should work, but older glib versions had a bug where
+	 * g_main_context_check() returns false even though events are pending.
+	 *
+	 * https://bugzilla.gnome.org/show_bug.cgi?id=11059
+	 */
+	(void)g_main_context_check(glue->gmain_ctx,
+				   glue->gpriority,
+				   glue->gpollfds,
+				   glue->num_gpollfds);
+
+	g_main_context_dispatch(glue->gmain_ctx);
+
+	ok = tevent_glib_prepare(glue);
+	if (!ok) {
+		return false;
+	}
+	glue->skip_glib_refresh = true;
+	return true;
+}
+
+static void tevent_glib_glue_trace_callback(enum tevent_trace_point point,
+					    void *private_data)
+{
+	struct tevent_glib_glue *glue = talloc_get_type_abort(
+		private_data, struct tevent_glib_glue);
+
+	if (point == TEVENT_TRACE_AFTER_LOOP_ONCE) {
+		if (!glue->skip_glib_refresh) {
+			tevent_glib_prepare(glue);
+		}
+		glue->skip_glib_refresh = false;
+	}
+
+	/* chain previous handler */
+	if (glue->prev_tevent_trace_cb != NULL) {
+		glue->prev_tevent_trace_cb(point, glue->prev_tevent_trace_data);
+	}
+}
+
+static void tevent_glib_glue_cleanup(struct tevent_glib_glue *glue)
+{
+	size_t n = talloc_array_length(glue->fd_map);
+	size_t i;
+
+	for (i = 0; i < n; i++) {
+		TALLOC_FREE(glue->fd_map[i]->fd_event);
+		TALLOC_FREE(glue->fd_map[i]);
+	}
+
+	tevent_set_trace_callback(glue->ev,
+				  glue->prev_tevent_trace_cb,
+				  glue->prev_tevent_trace_data);
+	glue->prev_tevent_trace_cb = NULL;
+	glue->prev_tevent_trace_data = NULL;
+
+	TALLOC_FREE(glue->fd_map);
+	glue->num_maps = 0;
+
+	TALLOC_FREE(glue->gpollfds);
+	glue->num_gpollfds = 0;
+
+	TALLOC_FREE(glue->prev_gpollfds);
+	glue->num_prev_gpollfds = 0;
+
+	TALLOC_FREE(glue->timer);
+	TALLOC_FREE(glue->acquire_retry_timer);
+	TALLOC_FREE(glue->im);
+
+	/*
+	 * These are not really needed, but let's wipe the slate clean.
+	 */
+	glue->skip_glib_refresh = false;
+	glue->gtimeout = 0;
+	glue->gpriority = 0;
+}
+
+static bool tevent_glib_glue_reinit(struct tevent_glib_glue *glue)
+{
+	tevent_glib_glue_cleanup(glue);
+
+	glue->im = tevent_create_immediate(glue);
+	if (glue->im == NULL) {
+		return false;
+	}
+
+	tevent_get_trace_callback(glue->ev,
+				  &glue->prev_tevent_trace_cb,
+				  &glue->prev_tevent_trace_data);
+	tevent_set_trace_callback(glue->ev,
+				  tevent_glib_glue_trace_callback,
+				  glue);
+
+	return true;
+}
+
+void samba_tevent_glib_glue_quit(struct tevent_glib_glue *glue)
+{
+	tevent_glib_glue_cleanup(glue);
+	glue->quit = true;
+	return;
+}
+
+struct tevent_glib_glue *samba_tevent_glib_glue_create(TALLOC_CTX *mem_ctx,
+						       struct tevent_context *ev,
+						       GMainContext *gmain_ctx)
+{
+	bool ok;
+	struct tevent_glib_glue *glue = NULL;
+
+	glue = talloc_zero(mem_ctx, struct tevent_glib_glue);
+	if (glue == NULL) {
+		DBG_ERR("talloc_zero failed\n");
+		return NULL;
+	}
+
+	*glue = (struct tevent_glib_glue) {
+		.ev = ev,
+		.gmain_ctx = gmain_ctx,
+	};
+
+	glue->im = tevent_create_immediate(glue);
+
+	tevent_get_trace_callback(glue->ev,
+				  &glue->prev_tevent_trace_cb,
+				  &glue->prev_tevent_trace_data);
+	tevent_set_trace_callback(glue->ev,
+				  tevent_glib_glue_trace_callback,
+				  glue);
+
+	ok = tevent_glib_prepare(glue);
+	if (!ok) {
+		TALLOC_FREE(glue);
+		return NULL;
+	}
+
+	return glue;
+}
+
+#else /* HAVE_GLIB */
+
+struct tevent_glib_glue *samba_tevent_glib_glue_create(TALLOC_CTX *mem_ctx,
+						       struct tevent_context *ev,
+						       GMainContext *gmain_ctx)
+{
+	errno = ENOSYS;
+	return NULL;
+}
+
+void samba_tevent_glib_glue_quit(struct tevent_glib_glue *glue)
+{
+	return;
+}
+#endif /* HAVE_GLIB */