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	diff --git a/lib/common/mainloop.c b/lib/common/mainloop.c
	index 229e751b48..76261342dd 100644
	--- a/lib/common/mainloop.c
	+++ b/lib/common/mainloop.c
	@@ -1,1483 +1,1481 @@
	/*
	* Copyright 2004-2024 the Pacemaker project contributors
	*
	* The version control history for this file may have further details.
	*
	* This source code is licensed under the GNU Lesser General Public License
	* version 2.1 or later (LGPLv2.1+) WITHOUT ANY WARRANTY.
	*/

	#include <crm_internal.h>

	#ifndef _GNU_SOURCE
	# define _GNU_SOURCE
	#endif

	#include <stdlib.h>
	#include <string.h>
	#include <signal.h>
	#include <errno.h>

	#include <sys/wait.h>

	#include <crm/crm.h>
	#include <crm/common/xml.h>
	#include <crm/common/mainloop.h>
	#include <crm/common/ipc_internal.h>

	#include <qb/qbarray.h>

	struct mainloop_child_s {
	pid_t pid;
	char *desc;
	unsigned timerid;
	gboolean timeout;
	void *privatedata;

	enum mainloop_child_flags flags;

	/* Called when a process dies */
	void (callback) (mainloop_child_t p, pid_t pid, int core, int signo, int exitcode);
	};

	struct trigger_s {
	GSource source;
	gboolean running;
	gboolean trigger;
	void *user_data;
	guint id;

	};

	struct mainloop_timer_s {
	guint id;
	guint period_ms;
	bool repeat;
	char *name;
	GSourceFunc cb;
	void *userdata;
	};

	static gboolean
	crm_trigger_prepare(GSource * source, gint * timeout)
	{
	crm_trigger_t trig = (crm_trigger_t ) source;

	/* cluster-glue's FD and IPC related sources make use of
	* g_source_add_poll() but do not set a timeout in their prepare
	* functions
	*
	* This means mainloop's poll() will block until an event for one
	* of these sources occurs - any /other/ type of source, such as
	* this one or g_idle_*, that doesn't use g_source_add_poll() is
	* S-O-L and won't be processed until there is something fd-based
	* happens.
	*
	* Luckily the timeout we can set here affects all sources and
	* puts an upper limit on how long poll() can take.
	*
	* So unconditionally set a small-ish timeout, not too small that
	* we're in constant motion, which will act as an upper bound on
	* how long the signal handling might be delayed for.
	*/
	timeout = 500; / Timeout in ms */

	return trig->trigger;
	}

	static gboolean
	crm_trigger_check(GSource * source)
	{
	crm_trigger_t trig = (crm_trigger_t ) source;

	return trig->trigger;
	}

	/*!
	* \internal
	* \brief GSource dispatch function for crm_trigger_t
	*
	* \param[in] source crm_trigger_t being dispatched
	* \param[in] callback Callback passed at source creation
	* \param[in,out] userdata User data passed at source creation
	*
	* \return G_SOURCE_REMOVE to remove source, G_SOURCE_CONTINUE to keep it
	*/
	static gboolean
	crm_trigger_dispatch(GSource *source, GSourceFunc callback, gpointer userdata)
	{
	gboolean rc = G_SOURCE_CONTINUE;
	crm_trigger_t trig = (crm_trigger_t ) source;

	if (trig->running) {
	/* Wait until the existing job is complete before starting the next one */
	return G_SOURCE_CONTINUE;
	}
	trig->trigger = FALSE;

	if (callback) {
	int callback_rc = callback(trig->user_data);

	if (callback_rc < 0) {
	crm_trace("Trigger handler %p not yet complete", trig);
	trig->running = TRUE;
	} else if (callback_rc == 0) {
	rc = G_SOURCE_REMOVE;
	}
	}
	return rc;
	}

	static void
	crm_trigger_finalize(GSource * source)
	{
	crm_trace("Trigger %p destroyed", source);
	}

	static GSourceFuncs crm_trigger_funcs = {
	crm_trigger_prepare,
	crm_trigger_check,
	crm_trigger_dispatch,
	crm_trigger_finalize,
	};

	static crm_trigger_t *
	mainloop_setup_trigger(GSource * source, int priority, int (*dispatch) (gpointer user_data),
	gpointer userdata)
	{
	crm_trigger_t *trigger = NULL;

	trigger = (crm_trigger_t *) source;

	trigger->id = 0;
	trigger->trigger = FALSE;
	trigger->user_data = userdata;

	if (dispatch) {
	g_source_set_callback(source, dispatch, trigger, NULL);
	}

	g_source_set_priority(source, priority);
	g_source_set_can_recurse(source, FALSE);

	trigger->id = g_source_attach(source, NULL);
	return trigger;
	}

	void
	mainloop_trigger_complete(crm_trigger_t * trig)
	{
	crm_trace("Trigger handler %p complete", trig);
	trig->running = FALSE;
	}

	/*!
	* \brief Create a trigger to be used as a mainloop source
	*
	* \param[in] priority Relative priority of source (lower number is higher priority)
	* \param[in] dispatch Trigger dispatch function (should return 0 to remove the
	* trigger from the mainloop, -1 if the trigger should be
	* kept but the job is still running and not complete, and
	* 1 if the trigger should be kept and the job is complete)
	* \param[in] userdata Pointer to pass to \p dispatch
	*
	* \return Newly allocated mainloop source for trigger
	*/
	crm_trigger_t *
	mainloop_add_trigger(int priority, int (*dispatch) (gpointer user_data),
	gpointer userdata)
	{
	GSource *source = NULL;

	CRM_ASSERT(sizeof(crm_trigger_t) > sizeof(GSource));
	source = g_source_new(&crm_trigger_funcs, sizeof(crm_trigger_t));

	return mainloop_setup_trigger(source, priority, dispatch, userdata);
	}

	void
	mainloop_set_trigger(crm_trigger_t * source)
	{
	if(source) {
	source->trigger = TRUE;
	}
	}

	gboolean
	mainloop_destroy_trigger(crm_trigger_t * source)
	{
	GSource *gs = NULL;

	if(source == NULL) {
	return TRUE;
	}

	gs = (GSource *)source;

	g_source_destroy(gs); /* Remove from mainloop, ref_count-- */
	g_source_unref(gs); /* The caller no longer carries a reference to source
	*
	* At this point the source should be free'd,
	* unless we're currently processing said
	* source, in which case mainloop holds an
	* additional reference and it will be free'd
	* once our processing completes
	*/
	return TRUE;
	}

	// Define a custom glib source for signal handling

	// Data structure for custom glib source
	typedef struct signal_s {
	crm_trigger_t trigger; // trigger that invoked source (must be first)
	void (*handler) (int sig); // signal handler
	int signal; // signal that was received
	} crm_signal_t;

	// Table to associate signal handlers with signal numbers
	static crm_signal_t *crm_signals[NSIG];

	/*!
	* \internal
	* \brief Dispatch an event from custom glib source for signals
	*
	* Given an signal event, clear the event trigger and call any registered
	* signal handler.
	*
	* \param[in] source glib source that triggered this dispatch
	* \param[in] callback (ignored)
	* \param[in] userdata (ignored)
	*/
	static gboolean
	crm_signal_dispatch(GSource *source, GSourceFunc callback, gpointer userdata)
	{
	crm_signal_t sig = (crm_signal_t ) source;

	if(sig->signal != SIGCHLD) {
	crm_notice("Caught '%s' signal "CRM_XS" %d (%s handler)",
	strsignal(sig->signal), sig->signal,
	(sig->handler? "invoking" : "no"));
	}

	sig->trigger.trigger = FALSE;
	if (sig->handler) {
	sig->handler(sig->signal);
	}
	return TRUE;
	}

	/*!
	* \internal
	* \brief Handle a signal by setting a trigger for signal source
	*
	* \param[in] sig Signal number that was received
	*
	* \note This is the true signal handler for the mainloop signal source, and
	* must be async-safe.
	*/
	static void
	mainloop_signal_handler(int sig)
	{
	if (sig > 0 && sig < NSIG && crm_signals[sig] != NULL) {
	mainloop_set_trigger((crm_trigger_t *) crm_signals[sig]);
	}
	}

	// Functions implementing our custom glib source for signal handling
	static GSourceFuncs crm_signal_funcs = {
	crm_trigger_prepare,
	crm_trigger_check,
	crm_signal_dispatch,
	crm_trigger_finalize,
	};

	/*!
	* \internal
	* \brief Set a true signal handler
	*
	* signal()-like interface to sigaction()
	*
	* \param[in] sig Signal number to register handler for
	* \param[in] dispatch Signal handler
	*
	* \return The previous value of the signal handler, or SIG_ERR on error
	* \note The dispatch function must be async-safe.
	*/
	sighandler_t
	crm_signal_handler(int sig, sighandler_t dispatch)
	{
	sigset_t mask;
	struct sigaction sa;
	struct sigaction old;

	if (sigemptyset(&mask) < 0) {
	crm_err("Could not set handler for signal %d: %s",
	sig, pcmk_rc_str(errno));
	return SIG_ERR;
	}

	memset(&sa, 0, sizeof(struct sigaction));
	sa.sa_handler = dispatch;
	sa.sa_flags = SA_RESTART;
	sa.sa_mask = mask;

	if (sigaction(sig, &sa, &old) < 0) {
	crm_err("Could not set handler for signal %d: %s",
	sig, pcmk_rc_str(errno));
	return SIG_ERR;
	}
	return old.sa_handler;
	}

	static void
	mainloop_destroy_signal_entry(int sig)
	{
	crm_signal_t *tmp = crm_signals[sig];

	crm_signals[sig] = NULL;

	crm_trace("Destroying signal %d", sig);
	mainloop_destroy_trigger((crm_trigger_t *) tmp);
	}

	/*!
	* \internal
	* \brief Add a signal handler to a mainloop
	*
	* \param[in] sig Signal number to handle
	* \param[in] dispatch Signal handler function
	*
	* \note The true signal handler merely sets a mainloop trigger to call this
	* dispatch function via the mainloop. Therefore, the dispatch function
	* does not need to be async-safe.
	*/
	gboolean
	mainloop_add_signal(int sig, void (*dispatch) (int sig))
	{
	GSource *source = NULL;
	int priority = G_PRIORITY_HIGH - 1;

	if (sig == SIGTERM) {
	/* TERM is higher priority than other signals,
	* signals are higher priority than other ipc.
	* Yes, minus: smaller is "higher"
	*/
	priority--;
	}

	if (sig >= NSIG \|\| sig < 0) {
	crm_err("Signal %d is out of range", sig);
	return FALSE;

	} else if (crm_signals[sig] != NULL && crm_signals[sig]->handler == dispatch) {
	crm_trace("Signal handler for %d is already installed", sig);
	return TRUE;

	} else if (crm_signals[sig] != NULL) {
	crm_err("Different signal handler for %d is already installed", sig);
	return FALSE;
	}

	CRM_ASSERT(sizeof(crm_signal_t) > sizeof(GSource));
	source = g_source_new(&crm_signal_funcs, sizeof(crm_signal_t));

	crm_signals[sig] = (crm_signal_t *) mainloop_setup_trigger(source, priority, NULL, NULL);
	CRM_ASSERT(crm_signals[sig] != NULL);

	crm_signals[sig]->handler = dispatch;
	crm_signals[sig]->signal = sig;

	if (crm_signal_handler(sig, mainloop_signal_handler) == SIG_ERR) {
	mainloop_destroy_signal_entry(sig);
	return FALSE;
	}

	return TRUE;
	}

	gboolean
	mainloop_destroy_signal(int sig)
	{
	if (sig >= NSIG \|\| sig < 0) {
	crm_err("Signal %d is out of range", sig);
	return FALSE;

	} else if (crm_signal_handler(sig, NULL) == SIG_ERR) {
	crm_perror(LOG_ERR, "Could not uninstall signal handler for signal %d", sig);
	return FALSE;

	} else if (crm_signals[sig] == NULL) {
	return TRUE;
	}
	mainloop_destroy_signal_entry(sig);
	return TRUE;
	}

	static qb_array_t *gio_map = NULL;

	void
	mainloop_cleanup(void)
	{
	if (gio_map) {
	qb_array_free(gio_map);
	}

	for (int sig = 0; sig < NSIG; ++sig) {
	mainloop_destroy_signal_entry(sig);
	}
	}

	/*
	* libqb...
	*/
	struct gio_to_qb_poll {
	int32_t is_used;
	guint source;
	int32_t events;
	void *data;
	qb_ipcs_dispatch_fn_t fn;
	enum qb_loop_priority p;
	};

	static gboolean
	gio_read_socket(GIOChannel * gio, GIOCondition condition, gpointer data)
	{
	struct gio_to_qb_poll adaptor = (struct gio_to_qb_poll )data;
	gint fd = g_io_channel_unix_get_fd(gio);

	crm_trace("%p.%d %d", data, fd, condition);

	/* if this assert get's hit, then there is a race condition between
	* when we destroy a fd and when mainloop actually gives it up */
	CRM_ASSERT(adaptor->is_used > 0);

	return (adaptor->fn(fd, condition, adaptor->data) == 0);
	}

	static void
	gio_poll_destroy(gpointer data)
	{
	struct gio_to_qb_poll adaptor = (struct gio_to_qb_poll )data;

	adaptor->is_used--;
	CRM_ASSERT(adaptor->is_used >= 0);

	if (adaptor->is_used == 0) {
	crm_trace("Marking adaptor %p unused", adaptor);
	adaptor->source = 0;
	}
	}

	/*!
	* \internal
	* \brief Convert libqb's poll priority into GLib's one
	*
	* \param[in] prio libqb's poll priority (#QB_LOOP_MED assumed as fallback)
	*
	* \return best matching GLib's priority
	*/
	static gint
	conv_prio_libqb2glib(enum qb_loop_priority prio)
	{
	switch (prio) {
	case QB_LOOP_LOW: return G_PRIORITY_LOW;
	case QB_LOOP_HIGH: return G_PRIORITY_HIGH;
	default: return G_PRIORITY_DEFAULT; // QB_LOOP_MED
	}
	}

	/*!
	* \internal
	* \brief Convert libqb's poll priority to rate limiting spec
	*
	* \param[in] prio libqb's poll priority (#QB_LOOP_MED assumed as fallback)
	*
	* \return best matching rate limiting spec
	* \note This is the inverse of libqb's qb_ipcs_request_rate_limit().
	*/
	static enum qb_ipcs_rate_limit
	conv_libqb_prio2ratelimit(enum qb_loop_priority prio)
	{
	switch (prio) {
	case QB_LOOP_LOW: return QB_IPCS_RATE_SLOW;
	case QB_LOOP_HIGH: return QB_IPCS_RATE_FAST;
	default: return QB_IPCS_RATE_NORMAL; // QB_LOOP_MED
	}
	}

	static int32_t
	gio_poll_dispatch_update(enum qb_loop_priority p, int32_t fd, int32_t evts,
	void *data, qb_ipcs_dispatch_fn_t fn, int32_t add)
	{
	struct gio_to_qb_poll *adaptor;
	GIOChannel *channel;
	int32_t res = 0;

	res = qb_array_index(gio_map, fd, (void **)&adaptor);
	if (res < 0) {
	crm_err("Array lookup failed for fd=%d: %d", fd, res);
	return res;
	}

	crm_trace("Adding fd=%d to mainloop as adaptor %p", fd, adaptor);

	if (add && adaptor->source) {
	crm_err("Adaptor for descriptor %d is still in-use", fd);
	return -EEXIST;
	}
	if (!add && !adaptor->is_used) {
	crm_err("Adaptor for descriptor %d is not in-use", fd);
	return -ENOENT;
	}

	/* channel is created with ref_count = 1 */
	channel = g_io_channel_unix_new(fd);
	if (!channel) {
	crm_err("No memory left to add fd=%d", fd);
	return -ENOMEM;
	}

	if (adaptor->source) {
	g_source_remove(adaptor->source);
	adaptor->source = 0;
	}

	/* Because unlike the poll() API, glib doesn't tell us about HUPs by default */
	evts \|= (G_IO_HUP \| G_IO_NVAL \| G_IO_ERR);

	adaptor->fn = fn;
	adaptor->events = evts;
	adaptor->data = data;
	adaptor->p = p;
	adaptor->is_used++;
	adaptor->source =
	g_io_add_watch_full(channel, conv_prio_libqb2glib(p), evts,
	gio_read_socket, adaptor, gio_poll_destroy);

	/* Now that mainloop now holds a reference to channel,
	* thanks to g_io_add_watch_full(), drop ours from g_io_channel_unix_new().
	*
	* This means that channel will be free'd by:
	* g_main_context_dispatch()
	* -> g_source_destroy_internal()
	* -> g_source_callback_unref()
	* shortly after gio_poll_destroy() completes
	*/
	g_io_channel_unref(channel);

	crm_trace("Added to mainloop with gsource id=%d", adaptor->source);
	if (adaptor->source > 0) {
	return 0;
	}

	return -EINVAL;
	}

	static int32_t
	gio_poll_dispatch_add(enum qb_loop_priority p, int32_t fd, int32_t evts,
	void *data, qb_ipcs_dispatch_fn_t fn)
	{
	return gio_poll_dispatch_update(p, fd, evts, data, fn, QB_TRUE);
	}

	static int32_t
	gio_poll_dispatch_mod(enum qb_loop_priority p, int32_t fd, int32_t evts,
	void *data, qb_ipcs_dispatch_fn_t fn)
	{
	return gio_poll_dispatch_update(p, fd, evts, data, fn, QB_FALSE);
	}

	static int32_t
	gio_poll_dispatch_del(int32_t fd)
	{
	struct gio_to_qb_poll *adaptor;

	crm_trace("Looking for fd=%d", fd);
	if (qb_array_index(gio_map, fd, (void **)&adaptor) == 0) {
	if (adaptor->source) {
	g_source_remove(adaptor->source);
	adaptor->source = 0;
	}
	}
	return 0;
	}

	struct qb_ipcs_poll_handlers gio_poll_funcs = {
	.job_add = NULL,
	.dispatch_add = gio_poll_dispatch_add,
	.dispatch_mod = gio_poll_dispatch_mod,
	.dispatch_del = gio_poll_dispatch_del,
	};

	static enum qb_ipc_type
	pick_ipc_type(enum qb_ipc_type requested)
	{
	const char *env = pcmk__env_option(PCMK__ENV_IPC_TYPE);

	if (env && strcmp("shared-mem", env) == 0) {
	return QB_IPC_SHM;
	} else if (env && strcmp("socket", env) == 0) {
	return QB_IPC_SOCKET;
	} else if (env && strcmp("posix", env) == 0) {
	return QB_IPC_POSIX_MQ;
	} else if (env && strcmp("sysv", env) == 0) {
	return QB_IPC_SYSV_MQ;
	} else if (requested == QB_IPC_NATIVE) {
	/* We prefer shared memory because the server never blocks on
	* send. If part of a message fits into the socket, libqb
	* needs to block until the remainder can be sent also.
	* Otherwise the client will wait forever for the remaining
	* bytes.
	*/
	return QB_IPC_SHM;
	}
	return requested;
	}

	qb_ipcs_service_t *
	mainloop_add_ipc_server(const char *name, enum qb_ipc_type type,
	struct qb_ipcs_service_handlers *callbacks)
	{
	return mainloop_add_ipc_server_with_prio(name, type, callbacks, QB_LOOP_MED);
	}

	qb_ipcs_service_t *
	mainloop_add_ipc_server_with_prio(const char *name, enum qb_ipc_type type,
	struct qb_ipcs_service_handlers *callbacks,
	enum qb_loop_priority prio)
	{
	int rc = 0;
	qb_ipcs_service_t *server = NULL;

	if (gio_map == NULL) {
	gio_map = qb_array_create_2(64, sizeof(struct gio_to_qb_poll), 1);
	}

	server = qb_ipcs_create(name, 0, pick_ipc_type(type), callbacks);

	if (server == NULL) {
	crm_err("Could not create %s IPC server: %s (%d)",
	name, pcmk_rc_str(errno), errno);
	return NULL;
	}

	if (prio != QB_LOOP_MED) {
	qb_ipcs_request_rate_limit(server, conv_libqb_prio2ratelimit(prio));
	}

	/* All clients should use at least ipc_buffer_max as their buffer size */
	qb_ipcs_enforce_buffer_size(server, crm_ipc_default_buffer_size());
	qb_ipcs_poll_handlers_set(server, &gio_poll_funcs);

	rc = qb_ipcs_run(server);
	if (rc < 0) {
	crm_err("Could not start %s IPC server: %s (%d)", name, pcmk_strerror(rc), rc);
	return NULL; // qb_ipcs_run() destroys server on failure
	}

	return server;
	}

	void
	mainloop_del_ipc_server(qb_ipcs_service_t * server)
	{
	if (server) {
	qb_ipcs_destroy(server);
	}
	}

	struct mainloop_io_s {
	char *name;
	void *userdata;

	int fd;
	guint source;
	crm_ipc_t *ipc;
	GIOChannel *channel;

	int (dispatch_fn_ipc) (const char buffer, ssize_t length, gpointer userdata);
	int (*dispatch_fn_io) (gpointer userdata);
	void (*destroy_fn) (gpointer userdata);

	};

	/*!
	* \internal
	* \brief I/O watch callback function (GIOFunc)
	*
	* \param[in] gio I/O channel being watched
	* \param[in] condition I/O condition satisfied
	* \param[in] data User data passed when source was created
	*
	* \return G_SOURCE_REMOVE to remove source, G_SOURCE_CONTINUE to keep it
	*/
	static gboolean
	mainloop_gio_callback(GIOChannel *gio, GIOCondition condition, gpointer data)
	{
	gboolean rc = G_SOURCE_CONTINUE;
	mainloop_io_t *client = data;

	CRM_ASSERT(client->fd == g_io_channel_unix_get_fd(gio));

	if (condition & G_IO_IN) {
	if (client->ipc) {
	long read_rc = 0L;
	int max = 10;

	do {
	read_rc = crm_ipc_read(client->ipc);
	if (read_rc <= 0) {
	crm_trace("Could not read IPC message from %s: %s (%ld)",
	client->name, pcmk_strerror(read_rc), read_rc);

	} else if (client->dispatch_fn_ipc) {
	const char *buffer = crm_ipc_buffer(client->ipc);

	crm_trace("New %ld-byte IPC message from %s "
	"after I/O condition %d",
	read_rc, client->name, (int) condition);
	if (client->dispatch_fn_ipc(buffer, read_rc, client->userdata) < 0) {
	crm_trace("Connection to %s no longer required", client->name);
	rc = G_SOURCE_REMOVE;
	}
	}

	} while ((rc == G_SOURCE_CONTINUE) && (read_rc > 0) && --max > 0);

	} else {
	crm_trace("New I/O event for %s after I/O condition %d",
	client->name, (int) condition);
	if (client->dispatch_fn_io) {
	if (client->dispatch_fn_io(client->userdata) < 0) {
	crm_trace("Connection to %s no longer required", client->name);
	rc = G_SOURCE_REMOVE;
	}
	}
	}
	}

	if (client->ipc && !crm_ipc_connected(client->ipc)) {
	crm_err("Connection to %s closed " CRM_XS "client=%p condition=%d",
	client->name, client, condition);
	rc = G_SOURCE_REMOVE;

	} else if (condition & (G_IO_HUP \| G_IO_NVAL \| G_IO_ERR)) {
	crm_trace("The connection %s[%p] has been closed (I/O condition=%d)",
	client->name, client, condition);
	rc = G_SOURCE_REMOVE;

	} else if ((condition & G_IO_IN) == 0) {
	/*
	#define GLIB_SYSDEF_POLLIN =1
	#define GLIB_SYSDEF_POLLPRI =2
	#define GLIB_SYSDEF_POLLOUT =4
	#define GLIB_SYSDEF_POLLERR =8
	#define GLIB_SYSDEF_POLLHUP =16
	#define GLIB_SYSDEF_POLLNVAL =32

	typedef enum
	{
	G_IO_IN GLIB_SYSDEF_POLLIN,
	G_IO_OUT GLIB_SYSDEF_POLLOUT,
	G_IO_PRI GLIB_SYSDEF_POLLPRI,
	G_IO_ERR GLIB_SYSDEF_POLLERR,
	G_IO_HUP GLIB_SYSDEF_POLLHUP,
	G_IO_NVAL GLIB_SYSDEF_POLLNVAL
	} GIOCondition;

	A bitwise combination representing a condition to watch for on an event source.

	G_IO_IN There is data to read.
	G_IO_OUT Data can be written (without blocking).
	G_IO_PRI There is urgent data to read.
	G_IO_ERR Error condition.
	G_IO_HUP Hung up (the connection has been broken, usually for pipes and sockets).
	G_IO_NVAL Invalid request. The file descriptor is not open.
	*/
	crm_err("Strange condition: %d", condition);
	}

	/* G_SOURCE_REMOVE results in mainloop_gio_destroy() being called
	* just before the source is removed from mainloop
	*/
	return rc;
	}

	static void
	mainloop_gio_destroy(gpointer c)
	{
	mainloop_io_t *client = c;
	char *c_name = strdup(client->name);

	/* client->source is valid but about to be destroyed (ref_count == 0) in gmain.c
	* client->channel will still have ref_count > 0... should be == 1
	*/
	crm_trace("Destroying client %s[%p]", c_name, c);

	if (client->ipc) {
	crm_ipc_close(client->ipc);
	}

	if (client->destroy_fn) {
	void (*destroy_fn) (gpointer userdata) = client->destroy_fn;

	client->destroy_fn = NULL;
	destroy_fn(client->userdata);
	}

	if (client->ipc) {
	crm_ipc_t *ipc = client->ipc;

	client->ipc = NULL;
	crm_ipc_destroy(ipc);
	}

	crm_trace("Destroyed client %s[%p]", c_name, c);

	free(client->name); client->name = NULL;
	free(client);

	free(c_name);
	}

	/*!
	* \brief Connect to IPC and add it as a main loop source
	*
	* \param[in,out] ipc IPC connection to add
	* \param[in] priority Event source priority to use for connection
	* \param[in] userdata Data to register with callbacks
	* \param[in] callbacks Dispatch and destroy callbacks for connection
	* \param[out] source Newly allocated event source
	*
	* \return Standard Pacemaker return code
	*
	* \note On failure, the caller is still responsible for ipc. On success, the
	* caller should call mainloop_del_ipc_client() when source is no longer
	* needed, which will lead to the disconnection of the IPC later in the
	* main loop if it is connected. However the IPC disconnects,
	* mainloop_gio_destroy() will free ipc and source after calling the
	* destroy callback.
	*/
	int
	pcmk__add_mainloop_ipc(crm_ipc_t ipc, int priority, void userdata,
	const struct ipc_client_callbacks *callbacks,
	mainloop_io_t **source)
	{
	int rc = pcmk_rc_ok;
	int fd = -1;
	const char *ipc_name = NULL;

	CRM_CHECK((ipc != NULL) && (callbacks != NULL), return EINVAL);

	ipc_name = pcmk__s(crm_ipc_name(ipc), "Pacemaker");
	rc = pcmk__connect_generic_ipc(ipc);
	if (rc != pcmk_rc_ok) {
	crm_debug("Connection to %s failed: %s", ipc_name, pcmk_rc_str(rc));
	return rc;
	}

	rc = pcmk__ipc_fd(ipc, &fd);
	if (rc != pcmk_rc_ok) {
	crm_debug("Could not obtain file descriptor for %s IPC: %s",
	ipc_name, pcmk_rc_str(rc));
	crm_ipc_close(ipc);
	return rc;
	}

	*source = mainloop_add_fd(ipc_name, priority, fd, userdata, NULL);
	if (*source == NULL) {
	rc = errno;
	crm_ipc_close(ipc);
	return rc;
	}

	(*source)->ipc = ipc;
	(*source)->destroy_fn = callbacks->destroy;
	(*source)->dispatch_fn_ipc = callbacks->dispatch;
	return pcmk_rc_ok;
	}

	/*!
	* \brief Get period for mainloop timer
	*
	* \param[in] timer Timer
	*
	* \return Period in ms
	*/
	guint
	pcmk__mainloop_timer_get_period(const mainloop_timer_t *timer)
	{
	if (timer) {
	return timer->period_ms;
	}
	return 0;
	}

	mainloop_io_t *
	mainloop_add_ipc_client(const char *name, int priority, size_t max_size,
	void userdata, struct ipc_client_callbacks callbacks)
	{
	crm_ipc_t *ipc = crm_ipc_new(name, max_size);
	mainloop_io_t *source = NULL;
	int rc = pcmk__add_mainloop_ipc(ipc, priority, userdata, callbacks,
	&source);

	if (rc != pcmk_rc_ok) {
	if (crm_log_level == LOG_STDOUT) {
	fprintf(stderr, "Connection to %s failed: %s",
	name, pcmk_rc_str(rc));
	}
	crm_ipc_destroy(ipc);
	if (rc > 0) {
	errno = rc;
	} else {
	errno = ENOTCONN;
	}
	return NULL;
	}
	return source;
	}

	void
	mainloop_del_ipc_client(mainloop_io_t * client)
	{
	mainloop_del_fd(client);
	}

	crm_ipc_t *
	mainloop_get_ipc_client(mainloop_io_t * client)
	{
	if (client) {
	return client->ipc;
	}
	return NULL;
	}

	mainloop_io_t *
	mainloop_add_fd(const char name, int priority, int fd, void userdata,
	struct mainloop_fd_callbacks * callbacks)
	{
	mainloop_io_t *client = NULL;

	if (fd >= 0) {
	client = calloc(1, sizeof(mainloop_io_t));
	if (client == NULL) {
	return NULL;
	}
	client->name = strdup(name);
	client->userdata = userdata;

	if (callbacks) {
	client->destroy_fn = callbacks->destroy;
	client->dispatch_fn_io = callbacks->dispatch;
	}

	client->fd = fd;
	client->channel = g_io_channel_unix_new(fd);
	client->source =
	g_io_add_watch_full(client->channel, priority,
	(G_IO_IN \| G_IO_HUP \| G_IO_NVAL \| G_IO_ERR), mainloop_gio_callback,
	client, mainloop_gio_destroy);

	/* Now that mainloop now holds a reference to channel,
	* thanks to g_io_add_watch_full(), drop ours from g_io_channel_unix_new().
	*
	* This means that channel will be free'd by:
	* g_main_context_dispatch() or g_source_remove()
	* -> g_source_destroy_internal()
	* -> g_source_callback_unref()
	* shortly after mainloop_gio_destroy() completes
	*/
	g_io_channel_unref(client->channel);
	crm_trace("Added connection %d for %s[%p].%d", client->source, client->name, client, fd);
	} else {
	errno = EINVAL;
	}

	return client;
	}

	void
	mainloop_del_fd(mainloop_io_t * client)
	{
	if (client != NULL) {
	crm_trace("Removing client %s[%p]", client->name, client);
	if (client->source) {
	/* Results in mainloop_gio_destroy() being called just
	* before the source is removed from mainloop
	*/
	g_source_remove(client->source);
	}
	}
	}

	static GList *child_list = NULL;

	pid_t
	mainloop_child_pid(mainloop_child_t * child)
	{
	return child->pid;
	}

	const char *
	mainloop_child_name(mainloop_child_t * child)
	{
	return child->desc;
	}

	int
	mainloop_child_timeout(mainloop_child_t * child)
	{
	return child->timeout;
	}

	void *
	mainloop_child_userdata(mainloop_child_t * child)
	{
	return child->privatedata;
	}

	void
	mainloop_clear_child_userdata(mainloop_child_t * child)
	{
	child->privatedata = NULL;
	}

	/* good function name */
	static void
	child_free(mainloop_child_t *child)
	{
	if (child->timerid != 0) {
	crm_trace("Removing timer %d", child->timerid);
	g_source_remove(child->timerid);
	child->timerid = 0;
	}
	free(child->desc);
	free(child);
	}

	/* terrible function name */
	static int
	child_kill_helper(mainloop_child_t *child)
	{
	int rc;
	if (child->flags & mainloop_leave_pid_group) {
	crm_debug("Kill pid %d only. leave group intact.", child->pid);
	rc = kill(child->pid, SIGKILL);
	} else {
	crm_debug("Kill pid %d's group", child->pid);
	rc = kill(-child->pid, SIGKILL);
	}

	if (rc < 0) {
	if (errno != ESRCH) {
	crm_perror(LOG_ERR, "kill(%d, KILL) failed", child->pid);
	}
	return -errno;
	}
	return 0;
	}

	static gboolean
	child_timeout_callback(gpointer p)
	{
	mainloop_child_t *child = p;
	int rc = 0;

	child->timerid = 0;
	if (child->timeout) {
	crm_warn("%s process (PID %d) will not die!", child->desc, (int)child->pid);
	return FALSE;
	}

	rc = child_kill_helper(child);
	if (rc == -ESRCH) {
	/* Nothing left to do. pid doesn't exist */
	return FALSE;
	}

	child->timeout = TRUE;
	crm_debug("%s process (PID %d) timed out", child->desc, (int)child->pid);

	child->timerid = g_timeout_add(5000, child_timeout_callback, child);
	return FALSE;
	}

	static bool
	child_waitpid(mainloop_child_t *child, int flags)
	{
	int rc = 0;
	int core = 0;
	int signo = 0;
	int status = 0;
	int exitcode = 0;
	bool callback_needed = true;

	rc = waitpid(child->pid, &status, flags);
	if (rc == 0) { // WNOHANG in flags, and child status is not available
	crm_trace("Child process %d (%s) still active",
	child->pid, child->desc);
	callback_needed = false;

	} else if (rc != child->pid) {
	/* According to POSIX, possible conditions:
	* - child->pid was non-positive (process group or any child),
	* and rc is specific child
	* - errno ECHILD (pid does not exist or is not child)
	* - errno EINVAL (invalid flags)
	* - errno EINTR (caller interrupted by signal)
	*
	* @TODO Handle these cases more specifically.
	*/
	signo = SIGCHLD;
	exitcode = 1;
	crm_notice("Wait for child process %d (%s) interrupted: %s",
	child->pid, child->desc, pcmk_rc_str(errno));

	} else if (WIFEXITED(status)) {
	exitcode = WEXITSTATUS(status);
	crm_trace("Child process %d (%s) exited with status %d",
	child->pid, child->desc, exitcode);

	} else if (WIFSIGNALED(status)) {
	signo = WTERMSIG(status);
	crm_trace("Child process %d (%s) exited with signal %d (%s)",
	child->pid, child->desc, signo, strsignal(signo));

	#ifdef WCOREDUMP // AIX, SunOS, maybe others
	} else if (WCOREDUMP(status)) {
	core = 1;
	crm_err("Child process %d (%s) dumped core",
	child->pid, child->desc);
	#endif

	} else { // flags must contain WUNTRACED and/or WCONTINUED to reach this
	crm_trace("Child process %d (%s) stopped or continued",
	child->pid, child->desc);
	callback_needed = false;
	}

	if (callback_needed && child->callback) {
	child->callback(child, child->pid, core, signo, exitcode);
	}
	return callback_needed;
	}

	static void
	child_death_dispatch(int signal)
	{
	for (GList *iter = child_list; iter; ) {
	GList *saved = iter;
	mainloop_child_t *child = iter->data;

	iter = iter->next;
	if (child_waitpid(child, WNOHANG)) {
	crm_trace("Removing completed process %d from child list",
	child->pid);
	child_list = g_list_remove_link(child_list, saved);
	g_list_free(saved);
	child_free(child);
	}
	}
	}

	static gboolean
	child_signal_init(gpointer p)
	{
	crm_trace("Installed SIGCHLD handler");
	/* Do NOT use g_child_watch_add() and friends, they rely on pthreads */
	mainloop_add_signal(SIGCHLD, child_death_dispatch);

	/* In case they terminated before the signal handler was installed */
	child_death_dispatch(SIGCHLD);
	return FALSE;
	}

	gboolean
	mainloop_child_kill(pid_t pid)
	{
	GList *iter;
	mainloop_child_t *child = NULL;
	mainloop_child_t *match = NULL;
	/* It is impossible to block SIGKILL, this allows us to
	* call waitpid without WNOHANG flag.*/
	int waitflags = 0, rc = 0;

	for (iter = child_list; iter != NULL && match == NULL; iter = iter->next) {
	child = iter->data;
	if (pid == child->pid) {
	match = child;
	}
	}

	if (match == NULL) {
	return FALSE;
	}

	rc = child_kill_helper(match);
	if(rc == -ESRCH) {
	/* It's gone, but hasn't shown up in waitpid() yet. Wait until we get
	* SIGCHLD and let handler clean it up as normal (so we get the correct
	* return code/status). The blocking alternative would be to call
	* child_waitpid(match, 0).
	*/
	crm_trace("Waiting for signal that child process %d completed",
	match->pid);
	return TRUE;

	} else if(rc != 0) {
	/* If KILL for some other reason set the WNOHANG flag since we
	* can't be certain what happened.
	*/
	waitflags = WNOHANG;
	}

	if (!child_waitpid(match, waitflags)) {
	/* not much we can do if this occurs */
	return FALSE;
	}

	child_list = g_list_remove(child_list, match);
	child_free(match);
	return TRUE;
	}

	/* Create/Log a new tracked process
	* To track a process group, use -pid
	*
	* @TODO Using a non-positive pid (i.e. any child, or process group) would
	* likely not be useful since we will free the child after the first
	* completed process.
	*/
	void
	mainloop_child_add_with_flags(pid_t pid, int timeout, const char desc, void privatedata, enum mainloop_child_flags flags,
	void (callback) (mainloop_child_t p, pid_t pid, int core, int signo, int exitcode))
	{
	static bool need_init = TRUE;
	mainloop_child_t *child = pcmk__assert_alloc(1, sizeof(mainloop_child_t));

	child->pid = pid;
	child->timerid = 0;
	child->timeout = FALSE;
	child->privatedata = privatedata;
	child->callback = callback;
	child->flags = flags;
	child->desc = pcmk__str_copy(desc);

	if (timeout) {
	child->timerid = g_timeout_add(timeout, child_timeout_callback, child);
	}

	child_list = g_list_append(child_list, child);

	if(need_init) {
	need_init = FALSE;
	/* SIGCHLD processing has to be invoked from mainloop.
	* We do not want it to be possible to both add a child pid
	* to mainloop, and have the pid's exit callback invoked within
	* the same callstack. */
	g_timeout_add(1, child_signal_init, NULL);
	}
	}

	void
	mainloop_child_add(pid_t pid, int timeout, const char desc, void privatedata,
	void (callback) (mainloop_child_t p, pid_t pid, int core, int signo, int exitcode))
	{
	mainloop_child_add_with_flags(pid, timeout, desc, privatedata, 0, callback);
	}

	static gboolean
	mainloop_timer_cb(gpointer user_data)
	{
	int id = 0;
	bool repeat = FALSE;
	struct mainloop_timer_s *t = user_data;

	CRM_ASSERT(t != NULL);

	id = t->id;
	t->id = 0; /* Ensure it's unset during callbacks so that
	* mainloop_timer_running() works as expected
	*/

	if(t->cb) {
	crm_trace("Invoking callbacks for timer %s", t->name);
	repeat = t->repeat;
	if(t->cb(t->userdata) == FALSE) {
	crm_trace("Timer %s complete", t->name);
	repeat = FALSE;
	}
	}

	if(repeat) {
	/* Restore if repeating */
	t->id = id;
	}

	return repeat;
	}

	bool
	mainloop_timer_running(mainloop_timer_t *t)
	{
	if(t && t->id != 0) {
	return TRUE;
	}
	return FALSE;
	}

	void
	mainloop_timer_start(mainloop_timer_t *t)
	{
	mainloop_timer_stop(t);
	if(t && t->period_ms > 0) {
	crm_trace("Starting timer %s", t->name);
	t->id = g_timeout_add(t->period_ms, mainloop_timer_cb, t);
	}
	}

	void
	mainloop_timer_stop(mainloop_timer_t *t)
	{
	if(t && t->id != 0) {
	crm_trace("Stopping timer %s", t->name);
	g_source_remove(t->id);
	t->id = 0;
	}
	}

	guint
	mainloop_timer_set_period(mainloop_timer_t *t, guint period_ms)
	{
	guint last = 0;

	if(t) {
	last = t->period_ms;
	t->period_ms = period_ms;
	}

	if(t && t->id != 0 && last != t->period_ms) {
	mainloop_timer_start(t);
	}
	return last;
	}

	mainloop_timer_t *
	mainloop_timer_add(const char name, guint period_ms, bool repeat, GSourceFunc cb, void userdata)
	{
	mainloop_timer_t *t = pcmk__assert_alloc(1, sizeof(mainloop_timer_t));

	- if(t) {
	- if(name) {
	- t->name = crm_strdup_printf("%s-%u-%d", name, period_ms, repeat);
	- } else {
	- t->name = crm_strdup_printf("%p-%u-%d", t, period_ms, repeat);
	- }
	- t->id = 0;
	- t->period_ms = period_ms;
	- t->repeat = repeat;
	- t->cb = cb;
	- t->userdata = userdata;
	- crm_trace("Created timer %s with %p %p", t->name, userdata, t->userdata);
	- }
	+ if (name != NULL) {
	+ t->name = crm_strdup_printf("%s-%u-%d", name, period_ms, repeat);
	+ } else {
	+ t->name = crm_strdup_printf("%p-%u-%d", t, period_ms, repeat);
	+ }
	+ t->id = 0;
	+ t->period_ms = period_ms;
	+ t->repeat = repeat;
	+ t->cb = cb;
	+ t->userdata = userdata;
	+ crm_trace("Created timer %s with %p %p", t->name, userdata, t->userdata);
	return t;
	}

	void
	mainloop_timer_del(mainloop_timer_t *t)
	{
	if(t) {
	crm_trace("Destroying timer %s", t->name);
	mainloop_timer_stop(t);
	free(t->name);
	free(t);
	}
	}

	/*
	* Helpers to make sure certain events aren't lost at shutdown
	*/

	static gboolean
	drain_timeout_cb(gpointer user_data)
	{
	bool timeout_popped = (bool) user_data;

	*timeout_popped = TRUE;
	return FALSE;
	}

	/*!
	* \brief Drain some remaining main loop events then quit it
	*
	* \param[in,out] mloop Main loop to drain and quit
	* \param[in] n Drain up to this many pending events
	*/
	void
	pcmk_quit_main_loop(GMainLoop *mloop, unsigned int n)
	{
	if ((mloop != NULL) && g_main_loop_is_running(mloop)) {
	GMainContext *ctx = g_main_loop_get_context(mloop);

	/* Drain up to n events in case some memory clean-up is pending
	* (helpful to reduce noise in valgrind output).
	*/
	for (int i = 0; (i < n) && g_main_context_pending(ctx); ++i) {
	g_main_context_dispatch(ctx);
	}
	g_main_loop_quit(mloop);
	}
	}

	/*!
	* \brief Process main loop events while a certain condition is met
	*
	* \param[in,out] mloop Main loop to process
	* \param[in] timer_ms Don't process longer than this amount of time
	* \param[in] check Function that returns true if events should be
	* processed
	*
	* \note This function is intended to be called at shutdown if certain important
	* events should not be missed. The caller would likely quit the main loop
	* or exit after calling this function. The check() function will be
	* passed the remaining timeout in milliseconds.
	*/
	void
	pcmk_drain_main_loop(GMainLoop mloop, guint timer_ms, bool (check)(guint))
	{
	bool timeout_popped = FALSE;
	guint timer = 0;
	GMainContext *ctx = NULL;

	CRM_CHECK(mloop && check, return);

	ctx = g_main_loop_get_context(mloop);
	if (ctx) {
	time_t start_time = time(NULL);

	timer = g_timeout_add(timer_ms, drain_timeout_cb, &timeout_popped);
	while (!timeout_popped
	&& check(timer_ms - (time(NULL) - start_time) * 1000)) {
	g_main_context_iteration(ctx, TRUE);
	}
	}
	if (!timeout_popped && (timer > 0)) {
	g_source_remove(timer);
	}
	}

	// Deprecated functions kept only for backward API compatibility
	// LCOV_EXCL_START

	#include <crm/common/mainloop_compat.h>

	gboolean
	crm_signal(int sig, void (*dispatch) (int sig))
	{
	return crm_signal_handler(sig, dispatch) != SIG_ERR;
	}

	// LCOV_EXCL_STOP
	// End deprecated API

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