/*
	 * Copyright 2009-2023 the Pacemaker project contributors
	 *
	 * The version control history for this file may have further details.
	 *
	 * This source code is licensed under the GNU General Public License version 2
	 * or later (GPLv2+) WITHOUT ANY WARRANTY.
	 */
	
	#include <crm_internal.h>
	
	#include <sys/param.h>
	#include <stdio.h>
	#include <sys/types.h>
	#include <sys/wait.h>
	#include <sys/stat.h>
	#include <unistd.h>
	#include <sys/utsname.h>
	
	#include <stdlib.h>
	#include <errno.h>
	#include <fcntl.h>
	#include <ctype.h>
	
	#include <crm/crm.h>
	#include <crm/msg_xml.h>
	#include <crm/common/ipc.h>
	#include <crm/common/ipc_internal.h>
	#include <crm/cluster/internal.h>
	#include <crm/common/mainloop.h>
	
	#include <crm/stonith-ng.h>
	#include <crm/fencing/internal.h>
	#include <crm/common/xml.h>
	
	#include <pacemaker-fenced.h>
	
	GHashTable *device_list = NULL;
	GHashTable *topology = NULL;
	static GList *cmd_list = NULL;
	
	static GHashTable *fenced_handlers = NULL;
	
	struct device_search_s {
	    /* target of fence action */
	    char *host;
	    /* requested fence action */
	    char *action;
	    /* timeout to use if a device is queried dynamically for possible targets */
	    int per_device_timeout;
	    /* number of registered fencing devices at time of request */
	    int replies_needed;
	    /* number of device replies received so far */
	    int replies_received;
	    /* whether the target is eligible to perform requested action (or off) */
	    bool allow_suicide;
	
	    /* private data to pass to search callback function */
	    void *user_data;
	    /* function to call when all replies have been received */
	    void (*callback) (GList * devices, void *user_data);
	    /* devices capable of performing requested action (or off if remapping) */
	    GList *capable;
	    /* Whether to perform searches that support the action */
	    uint32_t support_action_only;
	};
	
	static gboolean stonith_device_dispatch(gpointer user_data);
	static void st_child_done(int pid, const pcmk__action_result_t *result,
	                          void *user_data);
	
	static void search_devices_record_result(struct device_search_s *search, const char *device,
	                                         gboolean can_fence);
	
	static int get_agent_metadata(const char *agent, xmlNode **metadata);
	static void read_action_metadata(stonith_device_t *device);
	static enum fenced_target_by unpack_level_kind(const xmlNode *level);
	
	typedef struct async_command_s {
	
	    int id;
	    int pid;
	    int fd_stdout;
	    int options;
	    int default_timeout; /* seconds */
	    int timeout; /* seconds */
	
	    int start_delay; // seconds (-1 means disable static/random fencing delays)
	    int delay_id;
	
	    char *op;
	    char *origin;
	    char *client;
	    char *client_name;
	    char *remote_op_id;
	
	    char *target;
	    uint32_t target_nodeid;
	    char *action;
	    char *device;
	
	    GList *device_list;
	    GList *next_device_iter; // device_list entry for next device to execute
	
	    void *internal_user_data;
	    void (*done_cb) (int pid, const pcmk__action_result_t *result,
	                     void *user_data);
	    guint timer_sigterm;
	    guint timer_sigkill;
	    /*! If the operation timed out, this is the last signal
	     *  we sent to the process to get it to terminate */
	    int last_timeout_signo;
	
	    stonith_device_t *active_on;
	    stonith_device_t *activating_on;
	} async_command_t;
	
	static xmlNode *construct_async_reply(const async_command_t *cmd,
	                                      const pcmk__action_result_t *result);
	
	static gboolean
	is_action_required(const char *action, const stonith_device_t *device)
	{
	    return (device != NULL) && device->automatic_unfencing
	           && pcmk__str_eq(action, PCMK_ACTION_ON, pcmk__str_none);
	}
	
	static int
	get_action_delay_max(const stonith_device_t *device, const char *action)
	{
	    const char *value = NULL;
	    int delay_max = 0;
	
	    if (!pcmk__is_fencing_action(action)) {
	        return 0;
	    }
	
	    value = g_hash_table_lookup(device->params, PCMK_STONITH_DELAY_MAX);
	    if (value) {
	       delay_max = crm_parse_interval_spec(value) / 1000;
	    }
	
	    return delay_max;
	}
	
	static int
	get_action_delay_base(const stonith_device_t *device, const char *action,
	                      const char *target)
	{
	    char *hash_value = NULL;
	    int delay_base = 0;
	
	    if (!pcmk__is_fencing_action(action)) {
	        return 0;
	    }
	
	    hash_value = g_hash_table_lookup(device->params, PCMK_STONITH_DELAY_BASE);
	
	    if (hash_value) {
	        char *value = strdup(hash_value);
	        char *valptr = value;
	
	        CRM_ASSERT(value != NULL);
	
	        if (target != NULL) {
	            for (char *val = strtok(value, "; \t"); val != NULL; val = strtok(NULL, "; \t")) {
	                char *mapval = strchr(val, ':');
	
	                if (mapval == NULL || mapval[1] == 0) {
	                    crm_err("pcmk_delay_base: empty value in mapping", val);
	                    continue;
	                }
	
	                if (mapval != val && strncasecmp(target, val, (size_t)(mapval - val)) == 0) {
	                    value = mapval + 1;
	                    crm_debug("pcmk_delay_base mapped to %s for %s",
	                              value, target);
	                    break;
	                }
	            }
	        }
	
	        if (strchr(value, ':') == 0) {
	           delay_base = crm_parse_interval_spec(value) / 1000;
	        }
	
	        free(valptr);
	    }
	
	    return delay_base;
	}
	
	/*!
	 * \internal
	 * \brief Override STONITH timeout with pcmk_*_timeout if available
	 *
	 * \param[in] device           STONITH device to use
	 * \param[in] action           STONITH action name
	 * \param[in] default_timeout  Timeout to use if device does not have
	 *                             a pcmk_*_timeout parameter for action
	 *
	 * \return Value of pcmk_(action)_timeout if available, otherwise default_timeout
	 * \note For consistency, it would be nice if reboot/off/on timeouts could be
	 *       set the same way as start/stop/monitor timeouts, i.e. with an
	 *       <operation> entry in the fencing resource configuration. However that
	 *       is insufficient because fencing devices may be registered directly via
	 *       the fencer's register_device() API instead of going through the CIB
	 *       (e.g. stonith_admin uses it for its -R option, and the executor uses it
	 *       to ensure a device is registered when a command is issued). As device
	 *       properties, pcmk_*_timeout parameters can be grabbed by the fencer when
	 *       the device is registered, whether by CIB change or API call.
	 */
	static int
	get_action_timeout(const stonith_device_t *device, const char *action,
	                   int default_timeout)
	{
	    if (action && device && device->params) {
	        char buffer[64] = { 0, };
	        const char *value = NULL;
	
	        /* If "reboot" was requested but the device does not support it,
	         * we will remap to "off", so check timeout for "off" instead
	         */
	        if (pcmk__str_eq(action, PCMK_ACTION_REBOOT, pcmk__str_none)
	            && !pcmk_is_set(device->flags, st_device_supports_reboot)) {
	            crm_trace("%s doesn't support reboot, using timeout for off instead",
	                      device->id);
	            action = PCMK_ACTION_OFF;
	        }
	
	        /* If the device config specified an action-specific timeout, use it */
	        snprintf(buffer, sizeof(buffer), "pcmk_%s_timeout", action);
	        value = g_hash_table_lookup(device->params, buffer);
	        if (value) {
	            return atoi(value);
	        }
	    }
	    return default_timeout;
	}
	
	/*!
	 * \internal
	 * \brief Get the currently executing device for a fencing operation
	 *
	 * \param[in] cmd  Fencing operation to check
	 *
	 * \return Currently executing device for \p cmd if any, otherwise NULL
	 */
	static stonith_device_t *
	cmd_device(const async_command_t *cmd)
	{
	    if ((cmd == NULL) || (cmd->device == NULL) || (device_list == NULL)) {
	        return NULL;
	    }
	    return g_hash_table_lookup(device_list, cmd->device);
	}
	
	/*!
	 * \internal
	 * \brief Return the configured reboot action for a given device
	 *
	 * \param[in] device_id  Device ID
	 *
	 * \return Configured reboot action for \p device_id
	 */
	const char *
	fenced_device_reboot_action(const char *device_id)
	{
	    const char *action = NULL;
	
	    if ((device_list != NULL) && (device_id != NULL)) {
	        stonith_device_t *device = g_hash_table_lookup(device_list, device_id);
	
	        if ((device != NULL) && (device->params != NULL)) {
	            action = g_hash_table_lookup(device->params, "pcmk_reboot_action");
	        }
	    }
	    return pcmk__s(action, PCMK_ACTION_REBOOT);
	}
	
	/*!
	 * \internal
	 * \brief Check whether a given device supports the "on" action
	 *
	 * \param[in] device_id  Device ID
	 *
	 * \return true if \p device_id supports "on", otherwise false
	 */
	bool
	fenced_device_supports_on(const char *device_id)
	{
	    if ((device_list != NULL) && (device_id != NULL)) {
	        stonith_device_t *device = g_hash_table_lookup(device_list, device_id);
	
	        if (device != NULL) {
	            return pcmk_is_set(device->flags, st_device_supports_on);
	        }
	    }
	    return false;
	}
	
	static void
	free_async_command(async_command_t * cmd)
	{
	    if (!cmd) {
	        return;
	    }
	
	    if (cmd->delay_id) {
	        g_source_remove(cmd->delay_id);
	    }
	
	    cmd_list = g_list_remove(cmd_list, cmd);
	
	    g_list_free_full(cmd->device_list, free);
	    free(cmd->device);
	    free(cmd->action);
	    free(cmd->target);
	    free(cmd->remote_op_id);
	    free(cmd->client);
	    free(cmd->client_name);
	    free(cmd->origin);
	    free(cmd->op);
	    free(cmd);
	}
	
	/*!
	 * \internal
	 * \brief Create a new asynchronous fencing operation from request XML
	 *
	 * \param[in] msg  Fencing request XML (from IPC or CPG)
	 *
	 * \return Newly allocated fencing operation on success, otherwise NULL
	 *
	 * \note This asserts on memory errors, so a NULL return indicates an
	 *       unparseable message.
	 */
	static async_command_t *
	create_async_command(xmlNode *msg)
	{
	    xmlNode *op = NULL;
	    async_command_t *cmd = NULL;
	
	    if (msg == NULL) {
	        return NULL;
	    }
	
	    op = get_xpath_object("//@" F_STONITH_ACTION, msg, LOG_ERR);
	    if (op == NULL) {
	        return NULL;
	    }
	
	    cmd = calloc(1, sizeof(async_command_t));
	    CRM_ASSERT(cmd != NULL);
	
	    // All messages must include these
	    cmd->action = crm_element_value_copy(op, F_STONITH_ACTION);
	    cmd->op = crm_element_value_copy(msg, F_STONITH_OPERATION);
	    cmd->client = crm_element_value_copy(msg, F_STONITH_CLIENTID);
	    if ((cmd->action == NULL) || (cmd->op == NULL) || (cmd->client == NULL)) {
	        free_async_command(cmd);
	        return NULL;
	    }
	
	    crm_element_value_int(msg, F_STONITH_CALLID, &(cmd->id));
	    crm_element_value_int(msg, F_STONITH_CALLOPTS, &(cmd->options));
	    crm_element_value_int(msg, F_STONITH_DELAY, &(cmd->start_delay));
	    crm_element_value_int(msg, F_STONITH_TIMEOUT, &(cmd->default_timeout));
	    cmd->timeout = cmd->default_timeout;
	
	    cmd->origin = crm_element_value_copy(msg, F_ORIG);
	    cmd->remote_op_id = crm_element_value_copy(msg, F_STONITH_REMOTE_OP_ID);
	    cmd->client_name = crm_element_value_copy(msg, F_STONITH_CLIENTNAME);
	    cmd->target = crm_element_value_copy(op, F_STONITH_TARGET);
	    cmd->device = crm_element_value_copy(op, F_STONITH_DEVICE);
	
	    cmd->done_cb = st_child_done;
	
	    // Track in global command list
	    cmd_list = g_list_append(cmd_list, cmd);
	
	    return cmd;
	}
	
	static int
	get_action_limit(stonith_device_t * device)
	{
	    const char *value = NULL;
	    int action_limit = 1;
	
	    value = g_hash_table_lookup(device->params, PCMK_STONITH_ACTION_LIMIT);
	    if ((value == NULL)
	        || (pcmk__scan_min_int(value, &action_limit, INT_MIN) != pcmk_rc_ok)
	        || (action_limit == 0)) {
	        action_limit = 1;
	    }
	    return action_limit;
	}
	
	static int
	get_active_cmds(stonith_device_t * device)
	{
	    int counter = 0;
	    GList *gIter = NULL;
	    GList *gIterNext = NULL;
	
	    CRM_CHECK(device != NULL, return 0);
	
	    for (gIter = cmd_list; gIter != NULL; gIter = gIterNext) {
	        async_command_t *cmd = gIter->data;
	
	        gIterNext = gIter->next;
	
	        if (cmd->active_on == device) {
	            counter++;
	        }
	    }
	
	    return counter;
	}
	
	static void
	fork_cb(int pid, void *user_data)
	{
	    async_command_t *cmd = (async_command_t *) user_data;
	    stonith_device_t * device =
	        /* in case of a retry we've done the move from
	           activating_on to active_on already
	         */
	        cmd->activating_on?cmd->activating_on:cmd->active_on;
	
	    CRM_ASSERT(device);
	    crm_debug("Operation '%s' [%d]%s%s using %s now running with %ds timeout",
	              cmd->action, pid,
	              ((cmd->target == NULL)? "" : " targeting "),
	              pcmk__s(cmd->target, ""), device->id, cmd->timeout);
	    cmd->active_on = device;
	    cmd->activating_on = NULL;
	}
	
	static int
	get_agent_metadata_cb(gpointer data) {
	    stonith_device_t *device = data;
	    guint period_ms;
	
	    switch (get_agent_metadata(device->agent, &device->agent_metadata)) {
	        case pcmk_rc_ok:
	            if (device->agent_metadata) {
	                read_action_metadata(device);
	                stonith__device_parameter_flags(&(device->flags), device->id,
	                                        device->agent_metadata);
	            }
	            return G_SOURCE_REMOVE;
	
	        case EAGAIN:
	            period_ms = pcmk__mainloop_timer_get_period(device->timer);
	            if (period_ms < 160 * 1000) {
	                mainloop_timer_set_period(device->timer, 2 * period_ms);
	            }
	            return G_SOURCE_CONTINUE;
	
	        default:
	            return G_SOURCE_REMOVE;
	    }
	}
	
	/*!
	 * \internal
	 * \brief Call a command's action callback for an internal (not library) result
	 *
	 * \param[in,out] cmd               Command to report result for
	 * \param[in]     execution_status  Execution status to use for result
	 * \param[in]     exit_status       Exit status to use for result
	 * \param[in]     exit_reason       Exit reason to use for result
	 */
	static void
	report_internal_result(async_command_t *cmd, int exit_status,
	                       int execution_status, const char *exit_reason)
	{
	    pcmk__action_result_t result = PCMK__UNKNOWN_RESULT;
	
	    pcmk__set_result(&result, exit_status, execution_status, exit_reason);
	    cmd->done_cb(0, &result, cmd);
	    pcmk__reset_result(&result);
	}
	
	static gboolean
	stonith_device_execute(stonith_device_t * device)
	{
	    int exec_rc = 0;
	    const char *action_str = NULL;
	    const char *host_arg = NULL;
	    async_command_t *cmd = NULL;
	    stonith_action_t *action = NULL;
	    int active_cmds = 0;
	    int action_limit = 0;
	    GList *gIter = NULL;
	    GList *gIterNext = NULL;
	
	    CRM_CHECK(device != NULL, return FALSE);
	
	    active_cmds = get_active_cmds(device);
	    action_limit = get_action_limit(device);
	    if (action_limit > -1 && active_cmds >= action_limit) {
	        crm_trace("%s is over its action limit of %d (%u active action%s)",
	                  device->id, action_limit, active_cmds,
	                  pcmk__plural_s(active_cmds));
	        return TRUE;
	    }
	
	    for (gIter = device->pending_ops; gIter != NULL; gIter = gIterNext) {
	        async_command_t *pending_op = gIter->data;
	
	        gIterNext = gIter->next;
	
	        if (pending_op && pending_op->delay_id) {
	            crm_trace("Operation '%s'%s%s using %s was asked to run too early, "
	                      "waiting for start delay of %ds",
	                      pending_op->action,
	                      ((pending_op->target == NULL)? "" : " targeting "),
	                      pcmk__s(pending_op->target, ""),
	                      device->id, pending_op->start_delay);
	            continue;
	        }
	
	        device->pending_ops = g_list_remove_link(device->pending_ops, gIter);
	        g_list_free_1(gIter);
	
	        cmd = pending_op;
	        break;
	    }
	
	    if (cmd == NULL) {
	        crm_trace("No actions using %s are needed", device->id);
	        return TRUE;
	    }
	
	    if (pcmk__str_any_of(device->agent, STONITH_WATCHDOG_AGENT,
	                         STONITH_WATCHDOG_AGENT_INTERNAL, NULL)) {
	        if (pcmk__is_fencing_action(cmd->action)) {
	            if (node_does_watchdog_fencing(stonith_our_uname)) {
	                pcmk__panic(__func__);
	                goto done;
	            }
	        } else {
	            crm_info("Faking success for %s watchdog operation", cmd->action);
	            report_internal_result(cmd, CRM_EX_OK, PCMK_EXEC_DONE, NULL);
	            goto done;
	        }
	    }
	
	#if SUPPORT_CIBSECRETS
	    exec_rc = pcmk__substitute_secrets(device->id, device->params);
	    if (exec_rc != pcmk_rc_ok) {
	        if (pcmk__str_eq(cmd->action, PCMK_ACTION_STOP, pcmk__str_none)) {
	            crm_info("Proceeding with stop operation for %s "
	                     "despite being unable to load CIB secrets (%s)",
	                     device->id, pcmk_rc_str(exec_rc));
	        } else {
	            crm_err("Considering %s unconfigured "
	                    "because unable to load CIB secrets: %s",
	                     device->id, pcmk_rc_str(exec_rc));
	            report_internal_result(cmd, CRM_EX_ERROR, PCMK_EXEC_NO_SECRETS,
	                                   "Failed to get CIB secrets");
	            goto done;
	        }
	    }
	#endif
	
	    action_str = cmd->action;
	    if (pcmk__str_eq(cmd->action, PCMK_ACTION_REBOOT, pcmk__str_none)
	        && !pcmk_is_set(device->flags, st_device_supports_reboot)) {
	
	        crm_notice("Remapping 'reboot' action%s%s using %s to 'off' "
	                   "because agent '%s' does not support reboot",
	                   ((cmd->target == NULL)? "" : " targeting "),
	                   pcmk__s(cmd->target, ""), device->id, device->agent);
	        action_str = PCMK_ACTION_OFF;
	    }
	
	    if (pcmk_is_set(device->flags, st_device_supports_parameter_port)) {
	        host_arg = "port";
	
	    } else if (pcmk_is_set(device->flags, st_device_supports_parameter_plug)) {
	        host_arg = "plug";
	    }
	
	    action = stonith__action_create(device->agent, action_str, cmd->target,
	                                    cmd->target_nodeid, cmd->timeout,
	                                    device->params, device->aliases, host_arg);
	
	    /* for async exec, exec_rc is negative for early error exit
	       otherwise handling of success/errors is done via callbacks */
	    cmd->activating_on = device;
	    exec_rc = stonith__execute_async(action, (void *)cmd, cmd->done_cb,
	                                     fork_cb);
	    if (exec_rc < 0) {
	        cmd->activating_on = NULL;
	        cmd->done_cb(0, stonith__action_result(action), cmd);
	        stonith__destroy_action(action);
	    }
	
	done:
	    /* Device might get triggered to work by multiple fencing commands
	     * simultaneously. Trigger the device again to make sure any
	     * remaining concurrent commands get executed. */
	    if (device->pending_ops) {
	        mainloop_set_trigger(device->work);
	    }
	    return TRUE;
	}
	
	static gboolean
	stonith_device_dispatch(gpointer user_data)
	{
	    return stonith_device_execute(user_data);
	}
	
	static gboolean
	start_delay_helper(gpointer data)
	{
	    async_command_t *cmd = data;
	    stonith_device_t *device = cmd_device(cmd);
	
	    cmd->delay_id = 0;
	    if (device) {
	        mainloop_set_trigger(device->work);
	    }
	
	    return FALSE;
	}
	
	static void
	schedule_stonith_command(async_command_t * cmd, stonith_device_t * device)
	{
	    int delay_max = 0;
	    int delay_base = 0;
	    int requested_delay = cmd->start_delay;
	
	    CRM_CHECK(cmd != NULL, return);
	    CRM_CHECK(device != NULL, return);
	
	    if (cmd->device) {
	        free(cmd->device);
	    }
	
	    if (device->include_nodeid && (cmd->target != NULL)) {
	        crm_node_t *node = crm_get_peer(0, cmd->target);
	
	        cmd->target_nodeid = node->id;
	    }
	
	    cmd->device = strdup(device->id);
	    cmd->timeout = get_action_timeout(device, cmd->action, cmd->default_timeout);
	
	    if (cmd->remote_op_id) {
	        crm_debug("Scheduling '%s' action%s%s using %s for remote peer %s "
	                  "with op id %.8s and timeout %ds",
	                  cmd->action,
	                  (cmd->target == NULL)? "" : " targeting ",
	                  pcmk__s(cmd->target, ""),
	                  device->id, cmd->origin, cmd->remote_op_id, cmd->timeout);
	    } else {
	        crm_debug("Scheduling '%s' action%s%s using %s for %s with timeout %ds",
	                  cmd->action,
	                  (cmd->target == NULL)? "" : " targeting ",
	                  pcmk__s(cmd->target, ""),
	                  device->id, cmd->client, cmd->timeout);
	    }
	
	    device->pending_ops = g_list_append(device->pending_ops, cmd);
	    mainloop_set_trigger(device->work);
	
	    // Value -1 means disable any static/random fencing delays
	    if (requested_delay < 0) {
	        return;
	    }
	
	    delay_max = get_action_delay_max(device, cmd->action);
	    delay_base = get_action_delay_base(device, cmd->action, cmd->target);
	    if (delay_max == 0) {
	        delay_max = delay_base;
	    }
	    if (delay_max < delay_base) {
	        crm_warn(PCMK_STONITH_DELAY_BASE " (%ds) is larger than "
	                 PCMK_STONITH_DELAY_MAX " (%ds) for %s using %s "
	                 "(limiting to maximum delay)",
	                 delay_base, delay_max, cmd->action, device->id);
	        delay_base = delay_max;
	    }
	    if (delay_max > 0) {
	        // coverity[dontcall] It doesn't matter here if rand() is predictable
	        cmd->start_delay +=

	            ((delay_max != delay_base)?(rand() % (delay_max - delay_base)):0)
	            + delay_base;
	    }
	
	    if (cmd->start_delay > 0) {
	        crm_notice("Delaying '%s' action%s%s using %s for %ds " CRM_XS
	                   " timeout=%ds requested_delay=%ds base=%ds max=%ds",
	                   cmd->action,
	                   (cmd->target == NULL)? "" : " targeting ",
	                   pcmk__s(cmd->target, ""),
	                   device->id, cmd->start_delay, cmd->timeout,
	                   requested_delay, delay_base, delay_max);
	        cmd->delay_id =
	            g_timeout_add_seconds(cmd->start_delay, start_delay_helper, cmd);
	    }
	}
	
	static void
	free_device(gpointer data)
	{
	    GList *gIter = NULL;
	    stonith_device_t *device = data;
	
	    g_hash_table_destroy(device->params);
	    g_hash_table_destroy(device->aliases);
	
	    for (gIter = device->pending_ops; gIter != NULL; gIter = gIter->next) {
	        async_command_t *cmd = gIter->data;
	
	        crm_warn("Removal of device '%s' purged operation '%s'", device->id, cmd->action);
	        report_internal_result(cmd, CRM_EX_ERROR, PCMK_EXEC_NO_FENCE_DEVICE,
	                               "Device was removed before action could be executed");
	    }
	    g_list_free(device->pending_ops);
	
	    g_list_free_full(device->targets, free);
	
	    if (device->timer) {
	        mainloop_timer_stop(device->timer);
	        mainloop_timer_del(device->timer);
	    }
	
	    mainloop_destroy_trigger(device->work);
	
	    free_xml(device->agent_metadata);
	    free(device->namespace);
	    if (device->on_target_actions != NULL) {
	        g_string_free(device->on_target_actions, TRUE);
	    }
	    free(device->agent);
	    free(device->id);
	    free(device);
	}
	
	void free_device_list(void)
	{
	    if (device_list != NULL) {
	        g_hash_table_destroy(device_list);
	        device_list = NULL;
	    }
	}
	
	void
	init_device_list(void)
	{
	    if (device_list == NULL) {
	        device_list = pcmk__strkey_table(NULL, free_device);
	    }
	}
	
	static GHashTable *
	build_port_aliases(const char *hostmap, GList ** targets)
	{
	    char *name = NULL;
	    int last = 0, lpc = 0, max = 0, added = 0;
	    GHashTable *aliases = pcmk__strikey_table(free, free);
	
	    if (hostmap == NULL) {
	        return aliases;
	    }
	
	    max = strlen(hostmap);
	    for (; lpc <= max; lpc++) {
	        switch (hostmap[lpc]) {
	                /* Skip escaped chars */
	            case '\\':
	                lpc++;
	                break;
	
	                /* Assignment chars */
	            case '=':
	            case ':':
	                if (lpc > last) {
	                    free(name);
	                    name = calloc(1, 1 + lpc - last);
	                    memcpy(name, hostmap + last, lpc - last);
	                }
	                last = lpc + 1;
	                break;
	
	                /* Delimeter chars */
	                /* case ',': Potentially used to specify multiple ports */
	            case 0:
	            case ';':
	            case ' ':
	            case '\t':
	                if (name) {
	                    char *value = NULL;
	                    int k = 0;
	
	                    value = calloc(1, 1 + lpc - last);
	                    memcpy(value, hostmap + last, lpc - last);
	
	                    for (int i = 0; value[i] != '\0'; i++) {
	                        if (value[i] != '\\') {
	                            value[k++] = value[i];
	                        }
	                    }
	                    value[k] = '\0';
	
	                    crm_debug("Adding alias '%s'='%s'", name, value);
	                    g_hash_table_replace(aliases, name, value);
	                    if (targets) {
	                        *targets = g_list_append(*targets, strdup(value));
	                    }
	                    value = NULL;
	                    name = NULL;
	                    added++;
	
	                } else if (lpc > last) {
	                    crm_debug("Parse error at offset %d near '%s'", lpc - last, hostmap + last);
	                }
	
	                last = lpc + 1;
	                break;
	        }
	
	        if (hostmap[lpc] == 0) {
	            break;
	        }
	    }
	
	    if (added == 0) {
	        crm_info("No host mappings detected in '%s'", hostmap);
	    }
	
	    free(name);
	    return aliases;
	}
	
	GHashTable *metadata_cache = NULL;
	
	void
	free_metadata_cache(void) {
	    if (metadata_cache != NULL) {
	        g_hash_table_destroy(metadata_cache);
	        metadata_cache = NULL;
	    }
	}
	
	static void
	init_metadata_cache(void) {
	    if (metadata_cache == NULL) {
	        metadata_cache = pcmk__strkey_table(free, free);
	    }
	}
	
	int
	get_agent_metadata(const char *agent, xmlNode ** metadata)
	{
	    char *buffer = NULL;
	
	    if (metadata == NULL) {
	        return EINVAL;
	    }
	    *metadata = NULL;
	    if (pcmk__str_eq(agent, STONITH_WATCHDOG_AGENT_INTERNAL, pcmk__str_none)) {
	        return pcmk_rc_ok;
	    }
	    init_metadata_cache();
	    buffer = g_hash_table_lookup(metadata_cache, agent);
	    if (buffer == NULL) {
	        stonith_t *st = stonith_api_new();
	        int rc;
	
	        if (st == NULL) {
	            crm_warn("Could not get agent meta-data: "
	                     "API memory allocation failed");
	            return EAGAIN;
	        }
	        rc = st->cmds->metadata(st, st_opt_sync_call, agent,
	                                NULL, &buffer, 10);
	        stonith_api_delete(st);
	        if (rc || !buffer) {
	            crm_err("Could not retrieve metadata for fencing agent %s", agent);
	            return EAGAIN;
	        }
	        g_hash_table_replace(metadata_cache, strdup(agent), buffer);
	    }
	
	    *metadata = string2xml(buffer);
	    return pcmk_rc_ok;
	}
	
	static gboolean
	is_nodeid_required(xmlNode * xml)
	{
	    xmlXPathObjectPtr xpath = NULL;
	
	    if (stand_alone) {
	        return FALSE;
	    }
	
	    if (!xml) {
	        return FALSE;
	    }
	
	    xpath = xpath_search(xml, "//parameter[@name='nodeid']");
	    if (numXpathResults(xpath)  <= 0) {
	        freeXpathObject(xpath);
	        return FALSE;
	    }
	
	    freeXpathObject(xpath);
	    return TRUE;
	}
	
	static void
	read_action_metadata(stonith_device_t *device)
	{
	    xmlXPathObjectPtr xpath = NULL;
	    int max = 0;
	    int lpc = 0;
	
	    if (device->agent_metadata == NULL) {
	        return;
	    }
	
	    xpath = xpath_search(device->agent_metadata, "//action");
	    max = numXpathResults(xpath);
	
	    if (max <= 0) {
	        freeXpathObject(xpath);
	        return;
	    }
	
	    for (lpc = 0; lpc < max; lpc++) {
	        const char *action = NULL;
	        xmlNode *match = getXpathResult(xpath, lpc);
	
	        CRM_LOG_ASSERT(match != NULL);
	        if(match == NULL) { continue; };
	
	        action = crm_element_value(match, "name");
	
	        if (pcmk__str_eq(action, PCMK_ACTION_LIST, pcmk__str_none)) {
	            stonith__set_device_flags(device->flags, device->id,
	                                      st_device_supports_list);
	        } else if (pcmk__str_eq(action, PCMK_ACTION_STATUS, pcmk__str_none)) {
	            stonith__set_device_flags(device->flags, device->id,
	                                      st_device_supports_status);
	        } else if (pcmk__str_eq(action, PCMK_ACTION_REBOOT, pcmk__str_none)) {
	            stonith__set_device_flags(device->flags, device->id,
	                                      st_device_supports_reboot);
	        } else if (pcmk__str_eq(action, PCMK_ACTION_ON, pcmk__str_none)) {
	            /* "automatic" means the cluster will unfence node when it joins */
	            /* "required" is a deprecated synonym for "automatic" */
	            if (pcmk__xe_attr_is_true(match, "automatic") || pcmk__xe_attr_is_true(match, "required")) {
	                device->automatic_unfencing = TRUE;
	            }
	            stonith__set_device_flags(device->flags, device->id,
	                                      st_device_supports_on);
	        }
	
	        if ((action != NULL) && pcmk__xe_attr_is_true(match, "on_target")) {
	            pcmk__add_word(&(device->on_target_actions), 64, action);
	        }
	    }
	
	    freeXpathObject(xpath);
	}
	
	/*!
	 * \internal
	 * \brief Set a pcmk_*_action parameter if not already set
	 *
	 * \param[in,out] params  Device parameters
	 * \param[in]     action  Name of action
	 * \param[in]     value   Value to use if action is not already set
	 */
	static void
	map_action(GHashTable *params, const char *action, const char *value)
	{
	    char *key = crm_strdup_printf("pcmk_%s_action", action);
	
	    if (g_hash_table_lookup(params, key)) {
	        crm_warn("Ignoring %s='%s', see %s instead",
	                 STONITH_ATTR_ACTION_OP, value, key);
	        free(key);
	    } else {
	        crm_warn("Mapping %s='%s' to %s='%s'",
	                 STONITH_ATTR_ACTION_OP, value, key, value);
	        g_hash_table_insert(params, key, strdup(value));
	    }
	}
	
	/*!
	 * \internal
	 * \brief Create device parameter table from XML
	 *
	 * \param[in]  name    Device name (used for logging only)
	 * \param[in]  dev     XML containing device parameters
	 */
	static GHashTable *
	xml2device_params(const char *name, const xmlNode *dev)
	{
	    GHashTable *params = xml2list(dev);
	    const char *value;
	
	    /* Action should never be specified in the device configuration,
	     * but we support it for users who are familiar with other software
	     * that worked that way.
	     */
	    value = g_hash_table_lookup(params, STONITH_ATTR_ACTION_OP);
	    if (value != NULL) {
	        crm_warn("%s has '%s' parameter, which should never be specified in configuration",
	                 name, STONITH_ATTR_ACTION_OP);
	
	        if (*value == '\0') {
	            crm_warn("Ignoring empty '%s' parameter", STONITH_ATTR_ACTION_OP);
	
	        } else if (strcmp(value, PCMK_ACTION_REBOOT) == 0) {
	            crm_warn("Ignoring %s='reboot' (see stonith-action cluster property instead)",
	                     STONITH_ATTR_ACTION_OP);
	
	        } else if (strcmp(value, PCMK_ACTION_OFF) == 0) {
	            map_action(params, PCMK_ACTION_REBOOT, value);
	
	        } else {
	            map_action(params, PCMK_ACTION_OFF, value);
	            map_action(params, PCMK_ACTION_REBOOT, value);
	        }
	
	        g_hash_table_remove(params, STONITH_ATTR_ACTION_OP);
	    }
	
	    return params;
	}
	
	static const char *
	target_list_type(stonith_device_t * dev)
	{
	    const char *check_type = NULL;
	
	    check_type = g_hash_table_lookup(dev->params, PCMK_STONITH_HOST_CHECK);
	
	    if (check_type == NULL) {
	
	        if (g_hash_table_lookup(dev->params, PCMK_STONITH_HOST_LIST)) {
	            check_type = "static-list";
	        } else if (g_hash_table_lookup(dev->params, PCMK_STONITH_HOST_MAP)) {
	            check_type = "static-list";
	        } else if (pcmk_is_set(dev->flags, st_device_supports_list)) {
	            check_type = "dynamic-list";
	        } else if (pcmk_is_set(dev->flags, st_device_supports_status)) {
	            check_type = "status";
	        } else {
	            check_type = PCMK__VALUE_NONE;
	        }
	    }
	
	    return check_type;
	}
	
	static stonith_device_t *
	build_device_from_xml(xmlNode *dev)
	{
	    const char *value;
	    stonith_device_t *device = NULL;
	    char *agent = crm_element_value_copy(dev, "agent");
	
	    CRM_CHECK(agent != NULL, return device);
	
	    device = calloc(1, sizeof(stonith_device_t));
	
	    CRM_CHECK(device != NULL, {free(agent); return device;});
	
	    device->id = crm_element_value_copy(dev, XML_ATTR_ID);
	    device->agent = agent;
	    device->namespace = crm_element_value_copy(dev, "namespace");
	    device->params = xml2device_params(device->id, dev);
	
	    value = g_hash_table_lookup(device->params, PCMK_STONITH_HOST_LIST);
	    if (value) {
	        device->targets = stonith__parse_targets(value);
	    }
	
	    value = g_hash_table_lookup(device->params, PCMK_STONITH_HOST_MAP);
	    device->aliases = build_port_aliases(value, &(device->targets));
	
	    value = target_list_type(device);
	    if (!pcmk__str_eq(value, "static-list", pcmk__str_casei) && device->targets) {
	        /* Other than "static-list", dev-> targets is unnecessary. */
	        g_list_free_full(device->targets, free);
	        device->targets = NULL;
	    }
	    switch (get_agent_metadata(device->agent, &device->agent_metadata)) {
	        case pcmk_rc_ok:
	            if (device->agent_metadata) {
	                read_action_metadata(device);
	                stonith__device_parameter_flags(&(device->flags), device->id,
	                                                device->agent_metadata);
	            }
	            break;
	
	        case EAGAIN:
	            if (device->timer == NULL) {
	                device->timer = mainloop_timer_add("get_agent_metadata", 10 * 1000,
	                                           TRUE, get_agent_metadata_cb, device);
	            }
	            if (!mainloop_timer_running(device->timer)) {
	                mainloop_timer_start(device->timer);
	            }
	            break;
	
	        default:
	            break;
	    }
	
	    value = g_hash_table_lookup(device->params, "nodeid");
	    if (!value) {
	        device->include_nodeid = is_nodeid_required(device->agent_metadata);
	    }
	
	    value = crm_element_value(dev, "rsc_provides");
	    if (pcmk__str_eq(value, PCMK__VALUE_UNFENCING, pcmk__str_casei)) {
	        device->automatic_unfencing = TRUE;
	    }
	
	    if (is_action_required(PCMK_ACTION_ON, device)) {
	        crm_info("Fencing device '%s' requires unfencing", device->id);
	    }
	
	    if (device->on_target_actions != NULL) {
	        crm_info("Fencing device '%s' requires actions (%s) to be executed "
	                 "on target", device->id,
	                 (const char *) device->on_target_actions->str);
	    }
	
	    device->work = mainloop_add_trigger(G_PRIORITY_HIGH, stonith_device_dispatch, device);
	    /* TODO: Hook up priority */
	
	    return device;
	}
	
	static void
	schedule_internal_command(const char *origin,
	                          stonith_device_t * device,
	                          const char *action,
	                          const char *target,
	                          int timeout,
	                          void *internal_user_data,
	                          void (*done_cb) (int pid,
	                                           const pcmk__action_result_t *result,
	                                           void *user_data))
	{
	    async_command_t *cmd = NULL;
	
	    cmd = calloc(1, sizeof(async_command_t));
	
	    cmd->id = -1;
	    cmd->default_timeout = timeout ? timeout : 60;
	    cmd->timeout = cmd->default_timeout;
	    cmd->action = strdup(action);
	    pcmk__str_update(&cmd->target, target);
	    cmd->device = strdup(device->id);
	    cmd->origin = strdup(origin);
	    cmd->client = strdup(crm_system_name);
	    cmd->client_name = strdup(crm_system_name);
	
	    cmd->internal_user_data = internal_user_data;
	    cmd->done_cb = done_cb; /* cmd, not internal_user_data, is passed to 'done_cb' as the userdata */
	
	    schedule_stonith_command(cmd, device);
	}
	
	// Fence agent status commands use custom exit status codes
	enum fence_status_code {
	    fence_status_invalid    = -1,
	    fence_status_active     = 0,
	    fence_status_unknown    = 1,
	    fence_status_inactive   = 2,
	};
	
	static void
	status_search_cb(int pid, const pcmk__action_result_t *result, void *user_data)
	{
	    async_command_t *cmd = user_data;
	    struct device_search_s *search = cmd->internal_user_data;
	    stonith_device_t *dev = cmd_device(cmd);
	    gboolean can = FALSE;
	
	    free_async_command(cmd);
	
	    if (!dev) {
	        search_devices_record_result(search, NULL, FALSE);
	        return;
	    }
	
	    mainloop_set_trigger(dev->work);
	
	    if (result->execution_status != PCMK_EXEC_DONE) {
	        crm_warn("Assuming %s cannot fence %s "
	                 "because status could not be executed: %s%s%s%s",
	                 dev->id, search->host,
	                 pcmk_exec_status_str(result->execution_status),
	                 ((result->exit_reason == NULL)? "" : " ("),
	                 ((result->exit_reason == NULL)? "" : result->exit_reason),
	                 ((result->exit_reason == NULL)? "" : ")"));
	        search_devices_record_result(search, dev->id, FALSE);
	        return;
	    }
	
	    switch (result->exit_status) {
	        case fence_status_unknown:
	            crm_trace("%s reported it cannot fence %s", dev->id, search->host);
	            break;
	
	        case fence_status_active:
	        case fence_status_inactive:
	            crm_trace("%s reported it can fence %s", dev->id, search->host);
	            can = TRUE;
	            break;
	
	        default:
	            crm_warn("Assuming %s cannot fence %s "
	                     "(status returned unknown code %d)",
	                     dev->id, search->host, result->exit_status);
	            break;
	    }
	    search_devices_record_result(search, dev->id, can);
	}
	
	static void
	dynamic_list_search_cb(int pid, const pcmk__action_result_t *result,
	                       void *user_data)
	{
	    async_command_t *cmd = user_data;
	    struct device_search_s *search = cmd->internal_user_data;
	    stonith_device_t *dev = cmd_device(cmd);
	    gboolean can_fence = FALSE;
	
	    free_async_command(cmd);
	
	    /* Host/alias must be in the list output to be eligible to be fenced
	     *
	     * Will cause problems if down'd nodes aren't listed or (for virtual nodes)
	     *  if the guest is still listed despite being moved to another machine
	     */
	    if (!dev) {
	        search_devices_record_result(search, NULL, FALSE);
	        return;
	    }
	
	    mainloop_set_trigger(dev->work);
	
	    if (pcmk__result_ok(result)) {
	        crm_info("Refreshing target list for %s", dev->id);
	        g_list_free_full(dev->targets, free);
	        dev->targets = stonith__parse_targets(result->action_stdout);
	        dev->targets_age = time(NULL);
	
	    } else if (dev->targets != NULL) {
	        if (result->execution_status == PCMK_EXEC_DONE) {
	            crm_info("Reusing most recent target list for %s "
	                     "because list returned error code %d",
	                     dev->id, result->exit_status);
	        } else {
	            crm_info("Reusing most recent target list for %s "
	                     "because list could not be executed: %s%s%s%s",
	                     dev->id, pcmk_exec_status_str(result->execution_status),
	                     ((result->exit_reason == NULL)? "" : " ("),
	                     ((result->exit_reason == NULL)? "" : result->exit_reason),
	                     ((result->exit_reason == NULL)? "" : ")"));
	        }
	
	    } else { // We have never successfully executed list
	        if (result->execution_status == PCMK_EXEC_DONE) {
	            crm_warn("Assuming %s cannot fence %s "
	                     "because list returned error code %d",
	                     dev->id, search->host, result->exit_status);
	        } else {
	            crm_warn("Assuming %s cannot fence %s "
	                     "because list could not be executed: %s%s%s%s",
	                     dev->id, search->host,
	                     pcmk_exec_status_str(result->execution_status),
	                     ((result->exit_reason == NULL)? "" : " ("),
	                     ((result->exit_reason == NULL)? "" : result->exit_reason),
	                     ((result->exit_reason == NULL)? "" : ")"));
	        }
	
	        /* Fall back to pcmk_host_check="status" if the user didn't explicitly
	         * specify "dynamic-list".
	         */
	        if (g_hash_table_lookup(dev->params, PCMK_STONITH_HOST_CHECK) == NULL) {
	            crm_notice("Switching to pcmk_host_check='status' for %s", dev->id);
	            g_hash_table_replace(dev->params, strdup(PCMK_STONITH_HOST_CHECK),
	                                 strdup("status"));
	        }
	    }
	
	    if (dev->targets) {
	        const char *alias = g_hash_table_lookup(dev->aliases, search->host);
	
	        if (!alias) {
	            alias = search->host;
	        }
	        if (pcmk__str_in_list(alias, dev->targets, pcmk__str_casei)) {
	            can_fence = TRUE;
	        }
	    }
	    search_devices_record_result(search, dev->id, can_fence);
	}
	
	/*!
	 * \internal
	 * \brief Returns true if any key in first is not in second or second has a different value for key
	 */
	static int
	device_params_diff(GHashTable *first, GHashTable *second) {
	    char *key = NULL;
	    char *value = NULL;
	    GHashTableIter gIter;
	
	    g_hash_table_iter_init(&gIter, first);
	    while (g_hash_table_iter_next(&gIter, (void **)&key, (void **)&value)) {
	
	        if(strstr(key, "CRM_meta") == key) {
	            continue;
	        } else if(strcmp(key, "crm_feature_set") == 0) {
	            continue;
	        } else {
	            char *other_value = g_hash_table_lookup(second, key);
	
	            if (!other_value || !pcmk__str_eq(other_value, value, pcmk__str_casei)) {
	                crm_trace("Different value for %s: %s != %s", key, other_value, value);
	                return 1;
	            }
	        }
	    }
	
	    return 0;
	}
	
	/*!
	 * \internal
	 * \brief Checks to see if an identical device already exists in the device_list
	 */
	static stonith_device_t *
	device_has_duplicate(const stonith_device_t *device)
	{
	    stonith_device_t *dup = g_hash_table_lookup(device_list, device->id);
	
	    if (!dup) {
	        crm_trace("No match for %s", device->id);
	        return NULL;
	
	    } else if (!pcmk__str_eq(dup->agent, device->agent, pcmk__str_casei)) {
	        crm_trace("Different agent: %s != %s", dup->agent, device->agent);
	        return NULL;
	    }
	
	    /* Use calculate_operation_digest() here? */
	    if (device_params_diff(device->params, dup->params) ||
	        device_params_diff(dup->params, device->params)) {
	        return NULL;
	    }
	
	    crm_trace("Match");
	    return dup;
	}
	
	int
	stonith_device_register(xmlNode *dev, gboolean from_cib)
	{
	    stonith_device_t *dup = NULL;
	    stonith_device_t *device = build_device_from_xml(dev);
	    guint ndevices = 0;
	    int rv = pcmk_ok;
	
	    CRM_CHECK(device != NULL, return -ENOMEM);
	
	    /* do we have a watchdog-device? */
	    if (pcmk__str_eq(device->id, STONITH_WATCHDOG_ID, pcmk__str_none) ||
	        pcmk__str_any_of(device->agent, STONITH_WATCHDOG_AGENT,
	                     STONITH_WATCHDOG_AGENT_INTERNAL, NULL)) do {
	        if (stonith_watchdog_timeout_ms <= 0) {
	            crm_err("Ignoring watchdog fence device without "
	                    "stonith-watchdog-timeout set.");
	            rv = -ENODEV;
	            /* fall through to cleanup & return */
	        } else if (!pcmk__str_any_of(device->agent, STONITH_WATCHDOG_AGENT,
	                                 STONITH_WATCHDOG_AGENT_INTERNAL, NULL)) {
	            crm_err("Ignoring watchdog fence device with unknown "
	                    "agent '%s' unequal '" STONITH_WATCHDOG_AGENT "'.",
	                    device->agent?device->agent:"");
	            rv = -ENODEV;
	            /* fall through to cleanup & return */
	        } else if (!pcmk__str_eq(device->id, STONITH_WATCHDOG_ID,
	                                 pcmk__str_none)) {
	            crm_err("Ignoring watchdog fence device "
	                    "named %s !='"STONITH_WATCHDOG_ID"'.",
	                    device->id?device->id:"");
	            rv = -ENODEV;
	            /* fall through to cleanup & return */
	        } else {
	            if (pcmk__str_eq(device->agent, STONITH_WATCHDOG_AGENT,
	                             pcmk__str_none)) {
	                /* this either has an empty list or the targets
	                   configured for watchdog-fencing
	                 */
	                g_list_free_full(stonith_watchdog_targets, free);
	                stonith_watchdog_targets = device->targets;
	                device->targets = NULL;
	            }
	            if (node_does_watchdog_fencing(stonith_our_uname)) {
	                g_list_free_full(device->targets, free);
	                device->targets = stonith__parse_targets(stonith_our_uname);
	                g_hash_table_replace(device->params,
	                                     strdup(PCMK_STONITH_HOST_LIST),
	                                     strdup(stonith_our_uname));
	                /* proceed as with any other stonith-device */
	                break;
	            }
	
	            crm_debug("Skip registration of watchdog fence device on node not in host-list.");
	            /* cleanup and fall through to more cleanup and return */
	            device->targets = NULL;
	            stonith_device_remove(device->id, from_cib);
	        }
	        free_device(device);
	        return rv;
	    } while (0);
	
	    dup = device_has_duplicate(device);
	    if (dup) {
	        ndevices = g_hash_table_size(device_list);
	        crm_debug("Device '%s' already in device list (%d active device%s)",
	                  device->id, ndevices, pcmk__plural_s(ndevices));
	        free_device(device);
	        device = dup;
	        dup = g_hash_table_lookup(device_list, device->id);
	        dup->dirty = FALSE;
	
	    } else {
	        stonith_device_t *old = g_hash_table_lookup(device_list, device->id);
	
	        if (from_cib && old && old->api_registered) {
	            /* If the cib is writing over an entry that is shared with a stonith client,
	             * copy any pending ops that currently exist on the old entry to the new one.
	             * Otherwise the pending ops will be reported as failures
	             */
	            crm_info("Overwriting existing entry for %s from CIB", device->id);
	            device->pending_ops = old->pending_ops;
	            device->api_registered = TRUE;
	            old->pending_ops = NULL;
	            if (device->pending_ops) {
	                mainloop_set_trigger(device->work);
	            }
	        }
	        g_hash_table_replace(device_list, device->id, device);
	
	        ndevices = g_hash_table_size(device_list);
	        crm_notice("Added '%s' to device list (%d active device%s)",
	                   device->id, ndevices, pcmk__plural_s(ndevices));
	    }
	
	    if (from_cib) {
	        device->cib_registered = TRUE;
	    } else {
	        device->api_registered = TRUE;
	    }
	
	    return pcmk_ok;
	}
	
	void
	stonith_device_remove(const char *id, bool from_cib)
	{
	    stonith_device_t *device = g_hash_table_lookup(device_list, id);
	    guint ndevices = 0;
	
	    if (!device) {
	        ndevices = g_hash_table_size(device_list);
	        crm_info("Device '%s' not found (%d active device%s)",
	                 id, ndevices, pcmk__plural_s(ndevices));
	        return;
	    }
	
	    if (from_cib) {
	        device->cib_registered = FALSE;
	    } else {
	        device->verified = FALSE;
	        device->api_registered = FALSE;
	    }
	
	    if (!device->cib_registered && !device->api_registered) {
	        g_hash_table_remove(device_list, id);
	        ndevices = g_hash_table_size(device_list);
	        crm_info("Removed '%s' from device list (%d active device%s)",
	                 id, ndevices, pcmk__plural_s(ndevices));
	    } else {
	        crm_trace("Not removing '%s' from device list (%d active) because "
	                  "still registered via:%s%s",
	                  id, g_hash_table_size(device_list),
	                  (device->cib_registered? " cib" : ""),
	                  (device->api_registered? " api" : ""));
	    }
	}
	
	/*!
	 * \internal
	 * \brief Return the number of stonith levels registered for a node
	 *
	 * \param[in] tp  Node's topology table entry
	 *
	 * \return Number of non-NULL levels in topology entry
	 * \note This function is used only for log messages.
	 */
	static int
	count_active_levels(const stonith_topology_t *tp)
	{
	    int lpc = 0;
	    int count = 0;
	
	    for (lpc = 0; lpc < ST_LEVEL_MAX; lpc++) {
	        if (tp->levels[lpc] != NULL) {
	            count++;
	        }
	    }
	    return count;
	}
	
	static void
	free_topology_entry(gpointer data)
	{
	    stonith_topology_t *tp = data;
	
	    int lpc = 0;
	
	    for (lpc = 0; lpc < ST_LEVEL_MAX; lpc++) {
	        if (tp->levels[lpc] != NULL) {
	            g_list_free_full(tp->levels[lpc], free);
	        }
	    }
	    free(tp->target);
	    free(tp->target_value);
	    free(tp->target_pattern);
	    free(tp->target_attribute);
	    free(tp);
	}
	
	void
	free_topology_list(void)
	{
	    if (topology != NULL) {
	        g_hash_table_destroy(topology);
	        topology = NULL;
	    }
	}
	
	void
	init_topology_list(void)
	{
	    if (topology == NULL) {
	        topology = pcmk__strkey_table(NULL, free_topology_entry);
	    }
	}
	
	char *
	stonith_level_key(const xmlNode *level, enum fenced_target_by mode)
	{
	    if (mode == fenced_target_by_unknown) {
	        mode = unpack_level_kind(level);
	    }
	    switch (mode) {
	        case fenced_target_by_name:
	            return crm_element_value_copy(level, XML_ATTR_STONITH_TARGET);
	
	        case fenced_target_by_pattern:
	            return crm_element_value_copy(level, XML_ATTR_STONITH_TARGET_PATTERN);
	
	        case fenced_target_by_attribute:
	            return crm_strdup_printf("%s=%s",
	                crm_element_value(level, XML_ATTR_STONITH_TARGET_ATTRIBUTE),
	                crm_element_value(level, XML_ATTR_STONITH_TARGET_VALUE));
	
	        default:
	            return crm_strdup_printf("unknown-%s", ID(level));
	    }
	}
	
	/*!
	 * \internal
	 * \brief Parse target identification from topology level XML
	 *
	 * \param[in] level  Topology level XML to parse
	 *
	 * \return How to identify target of \p level
	 */
	static enum fenced_target_by
	unpack_level_kind(const xmlNode *level)
	{
	    if (crm_element_value(level, XML_ATTR_STONITH_TARGET) != NULL) {
	        return fenced_target_by_name;
	    }
	    if (crm_element_value(level, XML_ATTR_STONITH_TARGET_PATTERN) != NULL) {
	        return fenced_target_by_pattern;
	    }
	    if (!stand_alone /* if standalone, there's no attribute manager */
	        && (crm_element_value(level, XML_ATTR_STONITH_TARGET_ATTRIBUTE) != NULL)
	        && (crm_element_value(level, XML_ATTR_STONITH_TARGET_VALUE) != NULL)) {
	        return fenced_target_by_attribute;
	    }
	    return fenced_target_by_unknown;
	}
	
	static stonith_key_value_t *
	parse_device_list(const char *devices)
	{
	    int lpc = 0;
	    int max = 0;
	    int last = 0;
	    stonith_key_value_t *output = NULL;
	
	    if (devices == NULL) {
	        return output;
	    }
	
	    max = strlen(devices);
	    for (lpc = 0; lpc <= max; lpc++) {
	        if (devices[lpc] == ',' || devices[lpc] == 0) {
	            char *line = strndup(devices + last, lpc - last);
	
	            output = stonith_key_value_add(output, NULL, line);
	            free(line);
	
	            last = lpc + 1;
	        }
	    }
	
	    return output;
	}
	
	/*!
	 * \internal
	 * \brief Unpack essential information from topology request XML
	 *
	 * \param[in]  xml     Request XML to search
	 * \param[out] mode    If not NULL, where to store level kind
	 * \param[out] target  If not NULL, where to store representation of target
	 * \param[out] id      If not NULL, where to store level number
	 * \param[out] desc    If not NULL, where to store log-friendly level description
	 *
	 * \return Topology level XML from within \p xml, or NULL if not found
	 * \note The caller is responsible for freeing \p *target and \p *desc if set.
	 */
	static xmlNode *
	unpack_level_request(xmlNode *xml, enum fenced_target_by *mode, char **target,
	                     int *id, char **desc)
	{
	    enum fenced_target_by local_mode = fenced_target_by_unknown;
	    char *local_target = NULL;
	    int local_id = 0;
	
	    /* The level element can be the top element or lower. If top level, don't
	     * search by xpath, because it might give multiple hits if the XML is the
	     * CIB.
	     */
	    if ((xml != NULL) && !pcmk__xe_is(xml, XML_TAG_FENCING_LEVEL)) {
	        xml = get_xpath_object("//" XML_TAG_FENCING_LEVEL, xml, LOG_WARNING);
	    }
	
	    if (xml == NULL) {
	        if (desc != NULL) {
	            *desc = crm_strdup_printf("missing");
	        }
	    } else {
	        local_mode = unpack_level_kind(xml);
	        local_target = stonith_level_key(xml, local_mode);
	        crm_element_value_int(xml, XML_ATTR_STONITH_INDEX, &local_id);
	        if (desc != NULL) {
	            *desc = crm_strdup_printf("%s[%d]", local_target, local_id);
	        }
	    }
	
	    if (mode != NULL) {
	        *mode = local_mode;
	    }
	    if (id != NULL) {
	        *id = local_id;
	    }
	
	    if (target != NULL) {
	        *target = local_target;
	    } else {
	        free(local_target);
	    }
	
	    return xml;
	}
	
	/*!
	 * \internal
	 * \brief Register a fencing topology level for a target
	 *
	 * Given an XML request specifying the target name, level index, and device IDs
	 * for the level, this will create an entry for the target in the global topology
	 * table if one does not already exist, then append the specified device IDs to
	 * the entry's device list for the specified level.
	 *
	 * \param[in]  msg     XML request for STONITH level registration
	 * \param[out] desc    If not NULL, set to string representation "TARGET[LEVEL]"
	 * \param[out] result  Where to set result of registration
	 */
	void
	fenced_register_level(xmlNode *msg, char **desc, pcmk__action_result_t *result)
	{
	    int id = 0;
	    xmlNode *level;
	    enum fenced_target_by mode;
	    char *target;
	
	    stonith_topology_t *tp;
	    stonith_key_value_t *dIter = NULL;
	    stonith_key_value_t *devices = NULL;
	
	    CRM_CHECK((msg != NULL) && (result != NULL), return);
	
	    level = unpack_level_request(msg, &mode, &target, &id, desc);
	    if (level == NULL) {
	        fenced_set_protocol_error(result);
	        return;
	    }
	
	    // Ensure an ID was given (even the client API adds an ID)
	    if (pcmk__str_empty(ID(level))) {
	        crm_warn("Ignoring registration for topology level without ID");
	        free(target);
	        crm_log_xml_trace(level, "Bad level");
	        pcmk__format_result(result, CRM_EX_INVALID_PARAM, PCMK_EXEC_INVALID,
	                            "Topology level is invalid without ID");
	        return;
	    }
	
	    // Ensure a valid target was specified
	    if (mode == fenced_target_by_unknown) {
	        crm_warn("Ignoring registration for topology level '%s' "
	                 "without valid target", ID(level));
	        free(target);
	        crm_log_xml_trace(level, "Bad level");
	        pcmk__format_result(result, CRM_EX_INVALID_PARAM, PCMK_EXEC_INVALID,
	                            "Invalid target for topology level '%s'",
	                            ID(level));
	        return;
	    }
	
	    // Ensure level ID is in allowed range
	    if ((id <= 0) || (id >= ST_LEVEL_MAX)) {
	        crm_warn("Ignoring topology registration for %s with invalid level %d",
	                  target, id);
	        free(target);
	        crm_log_xml_trace(level, "Bad level");
	        pcmk__format_result(result, CRM_EX_INVALID_PARAM, PCMK_EXEC_INVALID,
	                            "Invalid level number '%s' for topology level '%s'",
	                            pcmk__s(crm_element_value(level,
	                                                      XML_ATTR_STONITH_INDEX),
	                                    ""),
	                            ID(level));
	        return;
	    }
	
	    /* Find or create topology table entry */
	    tp = g_hash_table_lookup(topology, target);
	    if (tp == NULL) {
	        tp = calloc(1, sizeof(stonith_topology_t));
	        if (tp == NULL) {
	            pcmk__set_result(result, CRM_EX_ERROR, PCMK_EXEC_ERROR,
	                             strerror(ENOMEM));
	            free(target);
	            return;
	        }
	        tp->kind = mode;
	        tp->target = target;
	        tp->target_value = crm_element_value_copy(level, XML_ATTR_STONITH_TARGET_VALUE);
	        tp->target_pattern = crm_element_value_copy(level, XML_ATTR_STONITH_TARGET_PATTERN);
	        tp->target_attribute = crm_element_value_copy(level, XML_ATTR_STONITH_TARGET_ATTRIBUTE);
	
	        g_hash_table_replace(topology, tp->target, tp);
	        crm_trace("Added %s (%d) to the topology (%d active entries)",
	                  target, (int) mode, g_hash_table_size(topology));
	    } else {
	        free(target);
	    }
	
	    if (tp->levels[id] != NULL) {
	        crm_info("Adding to the existing %s[%d] topology entry",
	                 tp->target, id);
	    }
	
	    devices = parse_device_list(crm_element_value(level, XML_ATTR_STONITH_DEVICES));
	    for (dIter = devices; dIter; dIter = dIter->next) {
	        const char *device = dIter->value;
	
	        crm_trace("Adding device '%s' for %s[%d]", device, tp->target, id);
	        tp->levels[id] = g_list_append(tp->levels[id], strdup(device));
	    }
	    stonith_key_value_freeall(devices, 1, 1);
	
	    {
	        int nlevels = count_active_levels(tp);
	
	        crm_info("Target %s has %d active fencing level%s",
	                 tp->target, nlevels, pcmk__plural_s(nlevels));
	    }
	
	    pcmk__set_result(result, CRM_EX_OK, PCMK_EXEC_DONE, NULL);
	}
	
	/*!
	 * \internal
	 * \brief Unregister a fencing topology level for a target
	 *
	 * Given an XML request specifying the target name and level index (or 0 for all
	 * levels), this will remove any corresponding entry for the target from the
	 * global topology table.
	 *
	 * \param[in]  msg     XML request for STONITH level registration
	 * \param[out] desc    If not NULL, set to string representation "TARGET[LEVEL]"
	 * \param[out] result  Where to set result of unregistration
	 */
	void
	fenced_unregister_level(xmlNode *msg, char **desc,
	                        pcmk__action_result_t *result)
	{
	    int id = -1;
	    stonith_topology_t *tp;
	    char *target;
	    xmlNode *level = NULL;
	
	    CRM_CHECK(result != NULL, return);
	
	    level = unpack_level_request(msg, NULL, &target, &id, desc);
	    if (level == NULL) {
	        fenced_set_protocol_error(result);
	        return;
	    }
	
	    // Ensure level ID is in allowed range
	    if ((id < 0) || (id >= ST_LEVEL_MAX)) {
	        crm_warn("Ignoring topology unregistration for %s with invalid level %d",
	                  target, id);
	        free(target);
	        crm_log_xml_trace(level, "Bad level");
	        pcmk__format_result(result, CRM_EX_INVALID_PARAM, PCMK_EXEC_INVALID,
	                            "Invalid level number '%s' for topology level %s",
	                            pcmk__s(crm_element_value(level,
	                                                      XML_ATTR_STONITH_INDEX),
	                                    "<null>"),
	
	                            // Client API doesn't add ID to unregistration XML
	                            pcmk__s(ID(level), ""));
	        return;
	    }
	
	    tp = g_hash_table_lookup(topology, target);
	    if (tp == NULL) {
	        guint nentries = g_hash_table_size(topology);
	
	        crm_info("No fencing topology found for %s (%d active %s)",
	                 target, nentries,
	                 pcmk__plural_alt(nentries, "entry", "entries"));
	
	    } else if (id == 0 && g_hash_table_remove(topology, target)) {
	        guint nentries = g_hash_table_size(topology);
	
	        crm_info("Removed all fencing topology entries related to %s "
	                 "(%d active %s remaining)", target, nentries,
	                 pcmk__plural_alt(nentries, "entry", "entries"));
	
	    } else if (tp->levels[id] != NULL) {
	        guint nlevels;
	
	        g_list_free_full(tp->levels[id], free);
	        tp->levels[id] = NULL;
	
	        nlevels = count_active_levels(tp);
	        crm_info("Removed level %d from fencing topology for %s "
	                 "(%d active level%s remaining)",
	                 id, target, nlevels, pcmk__plural_s(nlevels));
	    }
	
	    free(target);
	    pcmk__set_result(result, CRM_EX_OK, PCMK_EXEC_DONE, NULL);
	}
	
	static char *
	list_to_string(GList *list, const char *delim, gboolean terminate_with_delim)
	{
	    int max = g_list_length(list);
	    size_t delim_len = delim?strlen(delim):0;
	    size_t alloc_size = 1 + (max?((max-1+(terminate_with_delim?1:0))*delim_len):0);
	    char *rv;
	    GList *gIter;
	
	    for (gIter = list; gIter != NULL; gIter = gIter->next) {
	        const char *value = (const char *) gIter->data;
	
	        alloc_size += strlen(value);
	    }
	    rv = calloc(alloc_size, sizeof(char));
	    if (rv) {
	        char *pos = rv;
	        const char *lead_delim = "";
	
	        for (gIter = list; gIter != NULL; gIter = gIter->next) {
	            const char *value = (const char *) gIter->data;
	
	            pos = &pos[sprintf(pos, "%s%s", lead_delim, value)];
	            lead_delim = delim;
	        }
	        if (max && terminate_with_delim) {
	            sprintf(pos, "%s", delim);
	        }
	    }
	    return rv;
	}
	
	/*!
	 * \internal
	 * \brief Execute a fence agent action directly (and asynchronously)
	 *
	 * Handle a STONITH_OP_EXEC API message by scheduling a requested agent action
	 * directly on a specified device. Only list, monitor, and status actions are
	 * expected to use this call, though it should work with any agent command.
	 *
	 * \param[in]  msg     Request XML specifying action
	 * \param[out] result  Where to store result of action
	 *
	 * \note If the action is monitor, the device must be registered via the API
	 *       (CIB registration is not sufficient), because monitor should not be
	 *       possible unless the device is "started" (API registered).
	 */
	static void
	execute_agent_action(xmlNode *msg, pcmk__action_result_t *result)
	{
	    xmlNode *dev = get_xpath_object("//" F_STONITH_DEVICE, msg, LOG_ERR);
	    xmlNode *op = get_xpath_object("//@" F_STONITH_ACTION, msg, LOG_ERR);
	    const char *id = crm_element_value(dev, F_STONITH_DEVICE);
	    const char *action = crm_element_value(op, F_STONITH_ACTION);
	    async_command_t *cmd = NULL;
	    stonith_device_t *device = NULL;
	
	    if ((id == NULL) || (action == NULL)) {
	        crm_info("Malformed API action request: device %s, action %s",
	                 (id? id : "not specified"),
	                 (action? action : "not specified"));
	        fenced_set_protocol_error(result);
	        return;
	    }
	
	    if (pcmk__str_eq(id, STONITH_WATCHDOG_ID, pcmk__str_none)) {
	        // Watchdog agent actions are implemented internally
	        if (stonith_watchdog_timeout_ms <= 0) {
	            pcmk__set_result(result, CRM_EX_ERROR, PCMK_EXEC_NO_FENCE_DEVICE,
	                             "Watchdog fence device not configured");
	            return;
	
	        } else if (pcmk__str_eq(action, PCMK_ACTION_LIST, pcmk__str_none)) {
	            pcmk__set_result(result, CRM_EX_OK, PCMK_EXEC_DONE, NULL);
	            pcmk__set_result_output(result,
	                                    list_to_string(stonith_watchdog_targets,
	                                                   "\n", TRUE),
	                                    NULL);
	            return;
	
	        } else if (pcmk__str_eq(action, PCMK_ACTION_MONITOR, pcmk__str_none)) {
	            pcmk__set_result(result, CRM_EX_OK, PCMK_EXEC_DONE, NULL);
	            return;
	        }
	    }
	
	    device = g_hash_table_lookup(device_list, id);
	    if (device == NULL) {
	        crm_info("Ignoring API '%s' action request because device %s not found",
	                 action, id);
	        pcmk__format_result(result, CRM_EX_ERROR, PCMK_EXEC_NO_FENCE_DEVICE,
	                            "'%s' not found", id);
	        return;
	
	    } else if (!device->api_registered
	               && (strcmp(action, PCMK_ACTION_MONITOR) == 0)) {
	        // Monitors may run only on "started" (API-registered) devices
	        crm_info("Ignoring API '%s' action request because device %s not active",
	                 action, id);
	        pcmk__format_result(result, CRM_EX_ERROR, PCMK_EXEC_NO_FENCE_DEVICE,
	                            "'%s' not active", id);
	        return;
	    }
	
	    cmd = create_async_command(msg);
	    if (cmd == NULL) {
	        crm_log_xml_warn(msg, "invalid");
	        fenced_set_protocol_error(result);
	        return;
	    }
	
	    schedule_stonith_command(cmd, device);
	    pcmk__set_result(result, CRM_EX_OK, PCMK_EXEC_PENDING, NULL);
	}
	
	static void
	search_devices_record_result(struct device_search_s *search, const char *device, gboolean can_fence)
	{
	    search->replies_received++;
	    if (can_fence && device) {
	        if (search->support_action_only != st_device_supports_none) {
	            stonith_device_t *dev = g_hash_table_lookup(device_list, device);
	            if (dev && !pcmk_is_set(dev->flags, search->support_action_only)) {
	                return;
	            }
	        }
	        search->capable = g_list_append(search->capable, strdup(device));
	    }
	
	    if (search->replies_needed == search->replies_received) {
	
	        guint ndevices = g_list_length(search->capable);
	
	        crm_debug("Search found %d device%s that can perform '%s' targeting %s",
	                  ndevices, pcmk__plural_s(ndevices),
	                  (search->action? search->action : "unknown action"),
	                  (search->host? search->host : "any node"));
	
	        search->callback(search->capable, search->user_data);
	        free(search->host);
	        free(search->action);
	        free(search);
	    }
	}
	
	/*!
	 * \internal
	 * \brief Check whether the local host is allowed to execute a fencing action
	 *
	 * \param[in] device         Fence device to check
	 * \param[in] action         Fence action to check
	 * \param[in] target         Hostname of fence target
	 * \param[in] allow_suicide  Whether self-fencing is allowed for this operation
	 *
	 * \return TRUE if local host is allowed to execute action, FALSE otherwise
	 */
	static gboolean
	localhost_is_eligible(const stonith_device_t *device, const char *action,
	                      const char *target, gboolean allow_suicide)
	{
	    gboolean localhost_is_target = pcmk__str_eq(target, stonith_our_uname,
	                                                pcmk__str_casei);
	
	    if ((device != NULL) && (action != NULL)
	        && (device->on_target_actions != NULL)
	        && (strstr((const char*) device->on_target_actions->str,
	                   action) != NULL)) {
	
	        if (!localhost_is_target) {
	            crm_trace("Operation '%s' using %s can only be executed for local "
	                      "host, not %s", action, device->id, target);
	            return FALSE;
	        }
	
	    } else if (localhost_is_target && !allow_suicide) {
	        crm_trace("'%s' operation does not support self-fencing", action);
	        return FALSE;
	    }
	    return TRUE;
	}
	
	/*!
	 * \internal
	 * \brief Check if local node is allowed to execute (possibly remapped) action
	 *
	 * \param[in] device      Fence device to check
	 * \param[in] action      Fence action to check
	 * \param[in] target      Node name of fence target
	 * \param[in] allow_self  Whether self-fencing is allowed for this operation
	 *
	 * \return true if local node is allowed to execute \p action or any actions it
	 *         might be remapped to, otherwise false
	 */
	static bool
	localhost_is_eligible_with_remap(const stonith_device_t *device,
	                                 const char *action, const char *target,
	                                 gboolean allow_self)
	{
	    // Check exact action
	    if (localhost_is_eligible(device, action, target, allow_self)) {
	        return true;
	    }
	
	    // Check potential remaps
	
	    if (pcmk__str_eq(action, PCMK_ACTION_REBOOT, pcmk__str_none)) {
	        /* "reboot" might get remapped to "off" then "on", so even if reboot is
	         * disallowed, return true if either of those is allowed. We'll report
	         * the disallowed actions with the results. We never allow self-fencing
	         * for remapped "on" actions because the target is off at that point.
	         */
	        if (localhost_is_eligible(device, PCMK_ACTION_OFF, target, allow_self)
	            || localhost_is_eligible(device, PCMK_ACTION_ON, target, FALSE)) {
	            return true;
	        }
	    }
	
	    return false;
	}
	
	static void
	can_fence_host_with_device(stonith_device_t *dev,
	                           struct device_search_s *search)
	{
	    gboolean can = FALSE;
	    const char *check_type = "Internal bug";
	    const char *target = NULL;
	    const char *alias = NULL;
	    const char *dev_id = "Unspecified device";
	    const char *action = (search == NULL)? NULL : search->action;
	
	    CRM_CHECK((dev != NULL) && (action != NULL), goto search_report_results);
	
	    if (dev->id != NULL) {
	        dev_id = dev->id;
	    }
	
	    target = search->host;
	    if (target == NULL) {
	        can = TRUE;
	        check_type = "No target";
	        goto search_report_results;
	    }
	
	    /* Answer immediately if the device does not support the action
	     * or the local node is not allowed to perform it
	     */
	    if (pcmk__str_eq(action, PCMK_ACTION_ON, pcmk__str_none)
	        && !pcmk_is_set(dev->flags, st_device_supports_on)) {
	        check_type = "Agent does not support 'on'";
	        goto search_report_results;
	
	    } else if (!localhost_is_eligible_with_remap(dev, action, target,
	                                                 search->allow_suicide)) {
	        check_type = "This node is not allowed to execute action";
	        goto search_report_results;
	    }
	
	    // Check eligibility as specified by pcmk_host_check
	    check_type = target_list_type(dev);
	    alias = g_hash_table_lookup(dev->aliases, target);
	    if (pcmk__str_eq(check_type, PCMK__VALUE_NONE, pcmk__str_casei)) {
	        can = TRUE;
	
	    } else if (pcmk__str_eq(check_type, "static-list", pcmk__str_casei)) {
	        if (pcmk__str_in_list(target, dev->targets, pcmk__str_casei)) {
	            can = TRUE;
	        } else if (g_hash_table_lookup(dev->params, PCMK_STONITH_HOST_MAP)
	                   && g_hash_table_lookup(dev->aliases, target)) {
	            can = TRUE;
	        }
	
	    } else if (pcmk__str_eq(check_type, "dynamic-list", pcmk__str_casei)) {
	        time_t now = time(NULL);
	
	        if (dev->targets == NULL || dev->targets_age + 60 < now) {
	            int device_timeout = get_action_timeout(dev, PCMK_ACTION_LIST,
	                                                    search->per_device_timeout);
	
	            if (device_timeout > search->per_device_timeout) {
	                crm_notice("Since the pcmk_list_timeout(%ds) parameter of %s is larger than stonith-timeout(%ds), timeout may occur",
	                    device_timeout, dev_id, search->per_device_timeout);
	            }
	
	            crm_trace("Running '%s' to check whether %s is eligible to fence %s (%s)",
	                      check_type, dev_id, target, action);
	
	            schedule_internal_command(__func__, dev, PCMK_ACTION_LIST, NULL,
	                                      search->per_device_timeout, search, dynamic_list_search_cb);
	
	            /* we'll respond to this search request async in the cb */
	            return;
	        }
	
	        if (pcmk__str_in_list(((alias == NULL)? target : alias), dev->targets,
	                              pcmk__str_casei)) {
	            can = TRUE;
	        }
	
	    } else if (pcmk__str_eq(check_type, "status", pcmk__str_casei)) {
	        int device_timeout = get_action_timeout(dev, check_type, search->per_device_timeout);
	
	        if (device_timeout > search->per_device_timeout) {
	            crm_notice("Since the pcmk_status_timeout(%ds) parameter of %s is larger than stonith-timeout(%ds), timeout may occur",
	                device_timeout, dev_id, search->per_device_timeout);
	        }
	
	        crm_trace("Running '%s' to check whether %s is eligible to fence %s (%s)",
	                  check_type, dev_id, target, action);
	        schedule_internal_command(__func__, dev, PCMK_ACTION_STATUS, target,
	                                  search->per_device_timeout, search, status_search_cb);
	        /* we'll respond to this search request async in the cb */
	        return;
	    } else {
	        crm_err("Invalid value for " PCMK_STONITH_HOST_CHECK ": %s", check_type);
	        check_type = "Invalid " PCMK_STONITH_HOST_CHECK;
	    }
	
	  search_report_results:
	    crm_info("%s is%s eligible to fence (%s) %s%s%s%s: %s",
	             dev_id, (can? "" : " not"), pcmk__s(action, "unspecified action"),
	             pcmk__s(target, "unspecified target"),
	             (alias == NULL)? "" : " (as '", pcmk__s(alias, ""),
	             (alias == NULL)? "" : "')", check_type);
	    search_devices_record_result(search, ((dev == NULL)? NULL : dev_id), can);
	}
	
	static void
	search_devices(gpointer key, gpointer value, gpointer user_data)
	{
	    stonith_device_t *dev = value;
	    struct device_search_s *search = user_data;
	
	    can_fence_host_with_device(dev, search);
	}
	
	#define DEFAULT_QUERY_TIMEOUT 20
	static void
	get_capable_devices(const char *host, const char *action, int timeout, bool suicide, void *user_data,
	                    void (*callback) (GList * devices, void *user_data), uint32_t support_action_only)
	{
	    struct device_search_s *search;
	    guint ndevices = g_hash_table_size(device_list);
	
	    if (ndevices == 0) {
	        callback(NULL, user_data);
	        return;
	    }
	
	    search = calloc(1, sizeof(struct device_search_s));
	    if (!search) {
	        crm_crit("Cannot search for capable fence devices: %s",
	                 strerror(ENOMEM));
	        callback(NULL, user_data);
	        return;
	    }
	
	    pcmk__str_update(&search->host, host);
	    pcmk__str_update(&search->action, action);
	    search->per_device_timeout = timeout;
	    search->allow_suicide = suicide;
	    search->callback = callback;
	    search->user_data = user_data;
	    search->support_action_only = support_action_only;
	
	    /* We are guaranteed this many replies, even if a device is
	     * unregistered while the search is in progress.
	     */
	    search->replies_needed = ndevices;
	
	    crm_debug("Searching %d device%s to see which can execute '%s' targeting %s",
	              ndevices, pcmk__plural_s(ndevices),
	              (search->action? search->action : "unknown action"),
	              (search->host? search->host : "any node"));
	    g_hash_table_foreach(device_list, search_devices, search);
	}
	
	struct st_query_data {
	    xmlNode *reply;
	    char *remote_peer;
	    char *client_id;
	    char *target;
	    char *action;
	    int call_options;
	};
	
	/*!
	 * \internal
	 * \brief Add action-specific attributes to query reply XML
	 *
	 * \param[in,out] xml     XML to add attributes to
	 * \param[in]     action  Fence action
	 * \param[in]     device  Fence device
	 * \param[in]     target  Fence target
	 */
	static void
	add_action_specific_attributes(xmlNode *xml, const char *action,
	                               const stonith_device_t *device,
	                               const char *target)
	{
	    int action_specific_timeout;
	    int delay_max;
	    int delay_base;
	
	    CRM_CHECK(xml && action && device, return);
	
	    if (is_action_required(action, device)) {
	        crm_trace("Action '%s' is required using %s", action, device->id);
	        crm_xml_add_int(xml, F_STONITH_DEVICE_REQUIRED, 1);
	    }
	
	    action_specific_timeout = get_action_timeout(device, action, 0);
	    if (action_specific_timeout) {
	        crm_trace("Action '%s' has timeout %dms using %s",
	                  action, action_specific_timeout, device->id);
	        crm_xml_add_int(xml, F_STONITH_ACTION_TIMEOUT, action_specific_timeout);
	    }
	
	    delay_max = get_action_delay_max(device, action);
	    if (delay_max > 0) {
	        crm_trace("Action '%s' has maximum random delay %ds using %s",
	                  action, delay_max, device->id);
	        crm_xml_add_int(xml, F_STONITH_DELAY_MAX, delay_max);
	    }
	
	    delay_base = get_action_delay_base(device, action, target);
	    if (delay_base > 0) {
	        crm_xml_add_int(xml, F_STONITH_DELAY_BASE, delay_base);
	    }
	
	    if ((delay_max > 0) && (delay_base == 0)) {
	        crm_trace("Action '%s' has maximum random delay %ds using %s",
	                  action, delay_max, device->id);
	    } else if ((delay_max == 0) && (delay_base > 0)) {
	        crm_trace("Action '%s' has a static delay of %ds using %s",
	                  action, delay_base, device->id);
	    } else if ((delay_max > 0) && (delay_base > 0)) {
	        crm_trace("Action '%s' has a minimum delay of %ds and a randomly chosen "
	                  "maximum delay of %ds using %s",
	                  action, delay_base, delay_max, device->id);
	    }
	}
	
	/*!
	 * \internal
	 * \brief Add "disallowed" attribute to query reply XML if appropriate
	 *
	 * \param[in,out] xml            XML to add attribute to
	 * \param[in]     action         Fence action
	 * \param[in]     device         Fence device
	 * \param[in]     target         Fence target
	 * \param[in]     allow_suicide  Whether self-fencing is allowed
	 */
	static void
	add_disallowed(xmlNode *xml, const char *action, const stonith_device_t *device,
	               const char *target, gboolean allow_suicide)
	{
	    if (!localhost_is_eligible(device, action, target, allow_suicide)) {
	        crm_trace("Action '%s' using %s is disallowed for local host",
	                  action, device->id);
	        pcmk__xe_set_bool_attr(xml, F_STONITH_ACTION_DISALLOWED, true);
	    }
	}
	
	/*!
	 * \internal
	 * \brief Add child element with action-specific values to query reply XML
	 *
	 * \param[in,out] xml            XML to add attribute to
	 * \param[in]     action         Fence action
	 * \param[in]     device         Fence device
	 * \param[in]     target         Fence target
	 * \param[in]     allow_suicide  Whether self-fencing is allowed
	 */
	static void
	add_action_reply(xmlNode *xml, const char *action,
	                 const stonith_device_t *device, const char *target,
	                 gboolean allow_suicide)
	{
	    xmlNode *child = create_xml_node(xml, F_STONITH_ACTION);
	
	    crm_xml_add(child, XML_ATTR_ID, action);
	    add_action_specific_attributes(child, action, device, target);
	    add_disallowed(child, action, device, target, allow_suicide);
	}
	
	/*!
	 * \internal
	 * \brief Send a reply to a CPG peer or IPC client
	 *
	 * \param[in]     reply         XML reply to send
	 * \param[in]     call_options  Send synchronously if st_opt_sync_call is set
	 * \param[in]     remote_peer   If not NULL, name of peer node to send CPG reply
	 * \param[in,out] client        If not NULL, client to send IPC reply
	 */
	static void
	stonith_send_reply(const xmlNode *reply, int call_options,
	                   const char *remote_peer, pcmk__client_t *client)
	{
	    CRM_CHECK((reply != NULL) && ((remote_peer != NULL) || (client != NULL)),
	              return);
	
	    if (remote_peer == NULL) {
	        do_local_reply(reply, client, call_options);
	    } else {
	        send_cluster_message(crm_get_peer(0, remote_peer), crm_msg_stonith_ng,
	                             reply, FALSE);
	    }
	}
	
	static void
	stonith_query_capable_device_cb(GList * devices, void *user_data)
	{
	    struct st_query_data *query = user_data;
	    int available_devices = 0;
	    xmlNode *dev = NULL;
	    xmlNode *list = NULL;
	    GList *lpc = NULL;
	    pcmk__client_t *client = NULL;
	
	    if (query->client_id != NULL) {
	        client = pcmk__find_client_by_id(query->client_id);
	        if ((client == NULL) && (query->remote_peer == NULL)) {
	            crm_trace("Skipping reply to %s: no longer a client",
	                      query->client_id);
	            goto done;
	        }
	    }
	
	    /* Pack the results into XML */
	    list = create_xml_node(NULL, __func__);
	    crm_xml_add(list, F_STONITH_TARGET, query->target);
	    for (lpc = devices; lpc != NULL; lpc = lpc->next) {
	        stonith_device_t *device = g_hash_table_lookup(device_list, lpc->data);
	        const char *action = query->action;
	
	        if (!device) {
	            /* It is possible the device got unregistered while
	             * determining who can fence the target */
	            continue;
	        }
	
	        available_devices++;
	
	        dev = create_xml_node(list, F_STONITH_DEVICE);
	        crm_xml_add(dev, XML_ATTR_ID, device->id);
	        crm_xml_add(dev, "namespace", device->namespace);
	        crm_xml_add(dev, "agent", device->agent);
	        crm_xml_add_int(dev, F_STONITH_DEVICE_VERIFIED, device->verified);
	        crm_xml_add_int(dev, F_STONITH_DEVICE_SUPPORT_FLAGS, device->flags);
	
	        /* If the originating fencer wants to reboot the node, and we have a
	         * capable device that doesn't support "reboot", remap to "off" instead.
	         */
	        if (!pcmk_is_set(device->flags, st_device_supports_reboot)
	            && pcmk__str_eq(query->action, PCMK_ACTION_REBOOT,
	                            pcmk__str_none)) {
	            crm_trace("%s doesn't support reboot, using values for off instead",
	                      device->id);
	            action = PCMK_ACTION_OFF;
	        }
	
	        /* Add action-specific values if available */
	        add_action_specific_attributes(dev, action, device, query->target);
	        if (pcmk__str_eq(query->action, PCMK_ACTION_REBOOT, pcmk__str_none)) {
	            /* A "reboot" *might* get remapped to "off" then "on", so after
	             * sending the "reboot"-specific values in the main element, we add
	             * sub-elements for "off" and "on" values.
	             *
	             * We short-circuited earlier if "reboot", "off" and "on" are all
	             * disallowed for the local host. However if only one or two are
	             * disallowed, we send back the results and mark which ones are
	             * disallowed. If "reboot" is disallowed, this might cause problems
	             * with older fencer versions, which won't check for it. Older
	             * versions will ignore "off" and "on", so they are not a problem.
	             */
	            add_disallowed(dev, action, device, query->target,
	                           pcmk_is_set(query->call_options, st_opt_allow_suicide));
	            add_action_reply(dev, PCMK_ACTION_OFF, device, query->target,
	                             pcmk_is_set(query->call_options, st_opt_allow_suicide));
	            add_action_reply(dev, PCMK_ACTION_ON, device, query->target, FALSE);
	        }
	
	        /* A query without a target wants device parameters */
	        if (query->target == NULL) {
	            xmlNode *attrs = create_xml_node(dev, XML_TAG_ATTRS);
	
	            g_hash_table_foreach(device->params, hash2field, attrs);
	        }
	    }
	
	    crm_xml_add_int(list, F_STONITH_AVAILABLE_DEVICES, available_devices);
	    if (query->target) {
	        crm_debug("Found %d matching device%s for target '%s'",
	                  available_devices, pcmk__plural_s(available_devices),
	                  query->target);
	    } else {
	        crm_debug("%d device%s installed",
	                  available_devices, pcmk__plural_s(available_devices));
	    }
	
	    if (list != NULL) {
	        crm_log_xml_trace(list, "Add query results");
	        add_message_xml(query->reply, F_STONITH_CALLDATA, list);
	    }
	
	    stonith_send_reply(query->reply, query->call_options, query->remote_peer,
	                       client);
	
	done:
	    free_xml(query->reply);
	    free(query->remote_peer);
	    free(query->client_id);
	    free(query->target);
	    free(query->action);
	    free(query);
	    free_xml(list);
	    g_list_free_full(devices, free);
	}
	
	/*!
	 * \internal
	 * \brief Log the result of an asynchronous command
	 *
	 * \param[in] cmd        Command the result is for
	 * \param[in] result     Result of command
	 * \param[in] pid        Process ID of command, if available
	 * \param[in] next       Alternate device that will be tried if command failed
	 * \param[in] op_merged  Whether this command was merged with an earlier one
	 */
	static void
	log_async_result(const async_command_t *cmd,
	                 const pcmk__action_result_t *result,
	                 int pid, const char *next, bool op_merged)
	{
	    int log_level = LOG_ERR;
	    int output_log_level = LOG_NEVER;
	    guint devices_remaining = g_list_length(cmd->next_device_iter);
	
	    GString *msg = g_string_sized_new(80); // Reasonable starting size
	
	    // Choose log levels appropriately if we have a result
	    if (pcmk__result_ok(result)) {
	        log_level = (cmd->target == NULL)? LOG_DEBUG : LOG_NOTICE;
	        if ((result->action_stdout != NULL)
	            && !pcmk__str_eq(cmd->action, "metadata", pcmk__str_none)) {
	            output_log_level = LOG_DEBUG;
	        }
	        next = NULL;
	    } else {
	        log_level = (cmd->target == NULL)? LOG_NOTICE : LOG_ERR;
	        if ((result->action_stdout != NULL)
	            && !pcmk__str_eq(cmd->action, "metadata", pcmk__str_none)) {
	            output_log_level = LOG_WARNING;
	        }
	    }
	
	    // Build the log message piece by piece
	    pcmk__g_strcat(msg, "Operation '", cmd->action, "' ", NULL);
	    if (pid != 0) {
	        g_string_append_printf(msg, "[%d] ", pid);
	    }
	    if (cmd->target != NULL) {
	        pcmk__g_strcat(msg, "targeting ", cmd->target, " ", NULL);
	    }
	    if (cmd->device != NULL) {
	        pcmk__g_strcat(msg, "using ", cmd->device, " ", NULL);
	    }
	
	    // Add exit status or execution status as appropriate
	    if (result->execution_status == PCMK_EXEC_DONE) {
	        g_string_append_printf(msg, "returned %d", result->exit_status);
	    } else {
	        pcmk__g_strcat(msg, "could not be executed: ",
	                       pcmk_exec_status_str(result->execution_status), NULL);
	    }
	
	    // Add exit reason and next device if appropriate
	    if (result->exit_reason != NULL) {
	        pcmk__g_strcat(msg, " (", result->exit_reason, ")", NULL);
	    }
	    if (next != NULL) {
	        pcmk__g_strcat(msg, ", retrying with ", next, NULL);
	    }
	    if (devices_remaining > 0) {
	        g_string_append_printf(msg, " (%u device%s remaining)",
	                               (unsigned int) devices_remaining,
	                               pcmk__plural_s(devices_remaining));
	    }
	    g_string_append_printf(msg, " " CRM_XS " %scall %d from %s",
	                           (op_merged? "merged " : ""), cmd->id,
	                           cmd->client_name);
	
	    // Log the result
	    do_crm_log(log_level, "%s", msg->str);
	    g_string_free(msg, TRUE);
	
	    // Log the output (which may have multiple lines), if appropriate
	    if (output_log_level != LOG_NEVER) {
	        char *prefix = crm_strdup_printf("%s[%d]", cmd->device, pid);
	
	        crm_log_output(output_log_level, prefix, result->action_stdout);
	        free(prefix);
	    }
	}
	
	/*!
	 * \internal
	 * \brief Reply to requester after asynchronous command completion
	 *
	 * \param[in] cmd      Command that completed
	 * \param[in] result   Result of command
	 * \param[in] pid      Process ID of command, if available
	 * \param[in] merged   If true, command was merged with another, not executed
	 */
	static void
	send_async_reply(const async_command_t *cmd, const pcmk__action_result_t *result,
	                 int pid, bool merged)
	{
	    xmlNode *reply = NULL;
	    pcmk__client_t *client = NULL;
	
	    CRM_CHECK((cmd != NULL) && (result != NULL), return);
	
	    log_async_result(cmd, result, pid, NULL, merged);
	
	    if (cmd->client != NULL) {
	        client = pcmk__find_client_by_id(cmd->client);
	        if ((client == NULL) && (cmd->origin == NULL)) {
	            crm_trace("Skipping reply to %s: no longer a client", cmd->client);
	            return;
	        }
	    }
	
	    reply = construct_async_reply(cmd, result);
	    if (merged) {
	        pcmk__xe_set_bool_attr(reply, F_STONITH_MERGED, true);
	    }
	
	    if (!stand_alone && pcmk__is_fencing_action(cmd->action)
	        && pcmk__str_eq(cmd->origin, cmd->target, pcmk__str_casei)) {
	        /* The target was also the originator, so broadcast the result on its
	         * behalf (since it will be unable to).
	         */
	        crm_trace("Broadcast '%s' result for %s (target was also originator)",
	                  cmd->action, cmd->target);
	        crm_xml_add(reply, F_SUBTYPE, "broadcast");
	        crm_xml_add(reply, F_STONITH_OPERATION, T_STONITH_NOTIFY);
	        send_cluster_message(NULL, crm_msg_stonith_ng, reply, FALSE);
	    } else {
	        // Reply only to the originator
	        stonith_send_reply(reply, cmd->options, cmd->origin, client);
	    }
	
	    crm_log_xml_trace(reply, "Reply");
	    free_xml(reply);
	
	    if (stand_alone) {
	        /* Do notification with a clean data object */
	        xmlNode *notify_data = create_xml_node(NULL, T_STONITH_NOTIFY_FENCE);
	
	        stonith__xe_set_result(notify_data, result);
	        crm_xml_add(notify_data, F_STONITH_TARGET, cmd->target);
	        crm_xml_add(notify_data, F_STONITH_OPERATION, cmd->op);
	        crm_xml_add(notify_data, F_STONITH_DELEGATE, "localhost");
	        crm_xml_add(notify_data, F_STONITH_DEVICE, cmd->device);
	        crm_xml_add(notify_data, F_STONITH_REMOTE_OP_ID, cmd->remote_op_id);
	        crm_xml_add(notify_data, F_STONITH_ORIGIN, cmd->client);
	
	        fenced_send_notification(T_STONITH_NOTIFY_FENCE, result, notify_data);
	        fenced_send_notification(T_STONITH_NOTIFY_HISTORY, NULL, NULL);
	    }
	}
	
	static void
	cancel_stonith_command(async_command_t * cmd)
	{
	    stonith_device_t *device = cmd_device(cmd);
	
	    if (device) {
	        crm_trace("Cancel scheduled '%s' action using %s",
	                  cmd->action, device->id);
	        device->pending_ops = g_list_remove(device->pending_ops, cmd);
	    }
	}
	
	/*!
	 * \internal
	 * \brief Cancel and reply to any duplicates of a just-completed operation
	 *
	 * Check whether any fencing operations are scheduled to do the same thing as
	 * one that just succeeded. If so, rather than performing the same operation
	 * twice, return the result of this operation for all matching pending commands.
	 *
	 * \param[in,out] cmd     Fencing operation that just succeeded
	 * \param[in]     result  Result of \p cmd
	 * \param[in]     pid     If nonzero, process ID of agent invocation (for logs)
	 *
	 * \note Duplicate merging will do the right thing for either type of remapped
	 *       reboot. If the executing fencer remapped an unsupported reboot to off,
	 *       then cmd->action will be "reboot" and will be merged with any other
	 *       reboot requests. If the originating fencer remapped a topology reboot
	 *       to off then on, we will get here once with cmd->action "off" and once
	 *       with "on", and they will be merged separately with similar requests.
	 */
	static void
	reply_to_duplicates(async_command_t *cmd, const pcmk__action_result_t *result,
	                    int pid)
	{
	    GList *next = NULL;
	
	    for (GList *iter = cmd_list; iter != NULL; iter = next) {
	        async_command_t *cmd_other = iter->data;
	
	        next = iter->next; // We might delete this entry, so grab next now
	
	        if (cmd == cmd_other) {
	            continue;
	        }
	
	        /* A pending operation matches if:
	         * 1. The client connections are different.
	         * 2. The target is the same.
	         * 3. The fencing action is the same.
	         * 4. The device scheduled to execute the action is the same.
	         */
	        if (pcmk__str_eq(cmd->client, cmd_other->client, pcmk__str_casei) ||
	            !pcmk__str_eq(cmd->target, cmd_other->target, pcmk__str_casei) ||
	            !pcmk__str_eq(cmd->action, cmd_other->action, pcmk__str_none) ||
	            !pcmk__str_eq(cmd->device, cmd_other->device, pcmk__str_casei)) {
	
	            continue;
	        }
	
	        crm_notice("Merging fencing action '%s'%s%s originating from "
	                   "client %s with identical fencing request from client %s",
	                   cmd_other->action,
	                   (cmd_other->target == NULL)? "" : " targeting ",
	                   pcmk__s(cmd_other->target, ""), cmd_other->client_name,
	                   cmd->client_name);
	
	        // Stop tracking the duplicate, send its result, and cancel it
	        cmd_list = g_list_remove_link(cmd_list, iter);
	        send_async_reply(cmd_other, result, pid, true);
	        cancel_stonith_command(cmd_other);
	
	        free_async_command(cmd_other);
	        g_list_free_1(iter);
	    }
	}
	
	/*!
	 * \internal
	 * \brief Return the next required device (if any) for an operation
	 *
	 * \param[in,out] cmd  Fencing operation that just succeeded
	 *
	 * \return Next device required for action if any, otherwise NULL
	 */
	static stonith_device_t *
	next_required_device(async_command_t *cmd)
	{
	    for (GList *iter = cmd->next_device_iter; iter != NULL; iter = iter->next) {
	        stonith_device_t *next_device = g_hash_table_lookup(device_list,
	                                                            iter->data);
	
	        if (is_action_required(cmd->action, next_device)) {
	            /* This is only called for successful actions, so it's OK to skip
	             * non-required devices.
	             */
	            cmd->next_device_iter = iter->next;
	            return next_device;
	        }
	    }
	    return NULL;
	}
	
	static void
	st_child_done(int pid, const pcmk__action_result_t *result, void *user_data)
	{
	    async_command_t *cmd = user_data;
	
	    stonith_device_t *device = NULL;
	    stonith_device_t *next_device = NULL;
	
	    CRM_CHECK(cmd != NULL, return);
	
	    device = cmd_device(cmd);
	    cmd->active_on = NULL;
	
	    /* The device is ready to do something else now */
	    if (device) {
	        if (!device->verified && pcmk__result_ok(result)
	            && pcmk__strcase_any_of(cmd->action, PCMK_ACTION_LIST,
	                                    PCMK_ACTION_MONITOR, PCMK_ACTION_STATUS,
	                                    NULL)) {
	
	            device->verified = TRUE;
	        }
	
	        mainloop_set_trigger(device->work);
	    }
	
	    if (pcmk__result_ok(result)) {
	        next_device = next_required_device(cmd);
	
	    } else if ((cmd->next_device_iter != NULL)
	               && !is_action_required(cmd->action, device)) {
	        /* if this device didn't work out, see if there are any others we can try.
	         * if the failed device was 'required', we can't pick another device. */
	        next_device = g_hash_table_lookup(device_list,
	                                          cmd->next_device_iter->data);
	        cmd->next_device_iter = cmd->next_device_iter->next;
	    }
	
	    if (next_device == NULL) {
	        send_async_reply(cmd, result, pid, false);
	        if (pcmk__result_ok(result)) {
	            reply_to_duplicates(cmd, result, pid);
	        }
	        free_async_command(cmd);
	
	    } else { // This operation requires more fencing
	        log_async_result(cmd, result, pid, next_device->id, false);
	        schedule_stonith_command(cmd, next_device);
	    }
	}
	
	static gint
	sort_device_priority(gconstpointer a, gconstpointer b)
	{
	    const stonith_device_t *dev_a = a;
	    const stonith_device_t *dev_b = b;
	
	    if (dev_a->priority > dev_b->priority) {
	        return -1;
	    } else if (dev_a->priority < dev_b->priority) {
	        return 1;
	    }
	    return 0;
	}
	
	static void
	stonith_fence_get_devices_cb(GList * devices, void *user_data)
	{
	    async_command_t *cmd = user_data;
	    stonith_device_t *device = NULL;
	    guint ndevices = g_list_length(devices);
	
	    crm_info("Found %d matching device%s for target '%s'",
	             ndevices, pcmk__plural_s(ndevices), cmd->target);
	
	    if (devices != NULL) {
	        /* Order based on priority */
	        devices = g_list_sort(devices, sort_device_priority);
	        device = g_hash_table_lookup(device_list, devices->data);
	    }
	
	    if (device == NULL) { // No device found
	        pcmk__action_result_t result = PCMK__UNKNOWN_RESULT;
	
	        pcmk__format_result(&result, CRM_EX_ERROR, PCMK_EXEC_NO_FENCE_DEVICE,
	                            "No device configured for target '%s'",
	                            cmd->target);
	        send_async_reply(cmd, &result, 0, false);
	        pcmk__reset_result(&result);
	        free_async_command(cmd);
	        g_list_free_full(devices, free);
	
	    } else { // Device found, schedule it for fencing
	        cmd->device_list = devices;
	        cmd->next_device_iter = devices->next;
	        schedule_stonith_command(cmd, device);
	    }
	}
	
	/*!
	 * \internal
	 * \brief Execute a fence action via the local node
	 *
	 * \param[in]  msg     Fencing request
	 * \param[out] result  Where to store result of fence action
	 */
	static void
	fence_locally(xmlNode *msg, pcmk__action_result_t *result)
	{
	    const char *device_id = NULL;
	    stonith_device_t *device = NULL;
	    async_command_t *cmd = NULL;
	    xmlNode *dev = NULL;
	
	    CRM_CHECK((msg != NULL) && (result != NULL), return);
	
	    dev = get_xpath_object("//@" F_STONITH_TARGET, msg, LOG_ERR);
	
	    cmd = create_async_command(msg);
	    if (cmd == NULL) {
	        crm_log_xml_warn(msg, "invalid");
	        fenced_set_protocol_error(result);
	        return;
	    }
	
	    device_id = crm_element_value(dev, F_STONITH_DEVICE);
	    if (device_id != NULL) {
	        device = g_hash_table_lookup(device_list, device_id);
	        if (device == NULL) {
	            crm_err("Requested device '%s' is not available", device_id);
	            pcmk__format_result(result, CRM_EX_ERROR, PCMK_EXEC_NO_FENCE_DEVICE,
	                                "Requested device '%s' not found", device_id);
	            return;
	        }
	        schedule_stonith_command(cmd, device);
	
	    } else {
	        const char *host = crm_element_value(dev, F_STONITH_TARGET);
	
	        if (pcmk_is_set(cmd->options, st_opt_cs_nodeid)) {
	            int nodeid = 0;
	            crm_node_t *node = NULL;
	
	            pcmk__scan_min_int(host, &nodeid, 0);
	            node = pcmk__search_known_node_cache(nodeid, NULL, CRM_GET_PEER_ANY);
	            if (node != NULL) {
	                host = node->uname;
	            }
	        }
	
	        /* If we get to here, then self-fencing is implicitly allowed */
	        get_capable_devices(host, cmd->action, cmd->default_timeout,
	                            TRUE, cmd, stonith_fence_get_devices_cb,
	                            fenced_support_flag(cmd->action));
	    }
	
	    pcmk__set_result(result, CRM_EX_OK, PCMK_EXEC_PENDING, NULL);
	}
	
	/*!
	 * \internal
	 * \brief Build an XML reply for a fencing operation
	 *
	 * \param[in] request  Request that reply is for
	 * \param[in] data     If not NULL, add to reply as call data
	 * \param[in] result   Full result of fencing operation
	 *
	 * \return Newly created XML reply
	 * \note The caller is responsible for freeing the result.
	 * \note This has some overlap with construct_async_reply(), but that copies
	 *       values from an async_command_t, whereas this one copies them from the
	 *       request.
	 */
	xmlNode *
	fenced_construct_reply(const xmlNode *request, xmlNode *data,
	                       const pcmk__action_result_t *result)
	{
	    xmlNode *reply = NULL;
	
	    reply = create_xml_node(NULL, T_STONITH_REPLY);
	
	    crm_xml_add(reply, "st_origin", __func__);
	    crm_xml_add(reply, F_TYPE, T_STONITH_NG);
	    stonith__xe_set_result(reply, result);
	
	    if (request == NULL) {
	        /* Most likely, this is the result of a stonith operation that was
	         * initiated before we came up. Unfortunately that means we lack enough
	         * information to provide clients with a full result.
	         *
	         * @TODO Maybe synchronize this information at start-up?
	         */
	        crm_warn("Missing request information for client notifications for "
	                 "operation with result '%s' (initiated before we came up?)",
	                 pcmk_exec_status_str(result->execution_status));
	
	    } else {
	        const char *name = NULL;
	        const char *value = NULL;
	
	        // Attributes to copy from request to reply
	        const char *names[] = {
	            F_STONITH_OPERATION,
	            F_STONITH_CALLID,
	            F_STONITH_CLIENTID,
	            F_STONITH_CLIENTNAME,
	            F_STONITH_REMOTE_OP_ID,
	            F_STONITH_CALLOPTS
	        };
	
	        for (int lpc = 0; lpc < PCMK__NELEM(names); lpc++) {
	            name = names[lpc];
	            value = crm_element_value(request, name);
	            crm_xml_add(reply, name, value);
	        }
	        if (data != NULL) {
	            add_message_xml(reply, F_STONITH_CALLDATA, data);
	        }
	    }
	    return reply;
	}
	
	/*!
	 * \internal
	 * \brief Build an XML reply to an asynchronous fencing command
	 *
	 * \param[in] cmd     Fencing command that reply is for
	 * \param[in] result  Command result
	 */
	static xmlNode *
	construct_async_reply(const async_command_t *cmd,
	                      const pcmk__action_result_t *result)
	{
	    xmlNode *reply = create_xml_node(NULL, T_STONITH_REPLY);
	
	    crm_xml_add(reply, "st_origin", __func__);
	    crm_xml_add(reply, F_TYPE, T_STONITH_NG);
	    crm_xml_add(reply, F_STONITH_OPERATION, cmd->op);
	    crm_xml_add(reply, F_STONITH_DEVICE, cmd->device);
	    crm_xml_add(reply, F_STONITH_REMOTE_OP_ID, cmd->remote_op_id);
	    crm_xml_add(reply, F_STONITH_CLIENTID, cmd->client);
	    crm_xml_add(reply, F_STONITH_CLIENTNAME, cmd->client_name);
	    crm_xml_add(reply, F_STONITH_TARGET, cmd->target);
	    crm_xml_add(reply, F_STONITH_ACTION, cmd->op);
	    crm_xml_add(reply, F_STONITH_ORIGIN, cmd->origin);
	    crm_xml_add_int(reply, F_STONITH_CALLID, cmd->id);
	    crm_xml_add_int(reply, F_STONITH_CALLOPTS, cmd->options);
	
	    stonith__xe_set_result(reply, result);
	    return reply;
	}
	
	bool fencing_peer_active(crm_node_t *peer)
	{
	    if (peer == NULL) {
	        return FALSE;
	    } else if (peer->uname == NULL) {
	        return FALSE;
	    } else if (pcmk_is_set(peer->processes, crm_get_cluster_proc())) {
	        return TRUE;
	    }
	    return FALSE;
	}
	
	void
	set_fencing_completed(remote_fencing_op_t *op)
	{
	    struct timespec tv;
	
	    qb_util_timespec_from_epoch_get(&tv);
	    op->completed = tv.tv_sec;
	    op->completed_nsec = tv.tv_nsec;
	}
	
	/*!
	 * \internal
	 * \brief Look for alternate node needed if local node shouldn't fence target
	 *
	 * \param[in] target  Node that must be fenced
	 *
	 * \return Name of an alternate node that should fence \p target if any,
	 *         or NULL otherwise
	 */
	static const char *
	check_alternate_host(const char *target)
	{
	    if (pcmk__str_eq(target, stonith_our_uname, pcmk__str_casei)) {
	        GHashTableIter gIter;
	        crm_node_t *entry = NULL;
	
	        g_hash_table_iter_init(&gIter, crm_peer_cache);
	        while (g_hash_table_iter_next(&gIter, NULL, (void **)&entry)) {
	            if (fencing_peer_active(entry)
	                && !pcmk__str_eq(entry->uname, target, pcmk__str_casei)) {
	                crm_notice("Forwarding self-fencing request to %s",
	                           entry->uname);
	                return entry->uname;
	            }
	        }
	        crm_warn("Will handle own fencing because no peer can");
	    }
	    return NULL;
	}
	
	static void 
	remove_relay_op(xmlNode * request)
	{
	    xmlNode *dev = get_xpath_object("//@" F_STONITH_ACTION, request, LOG_TRACE);
	    const char *relay_op_id = NULL; 
	    const char *op_id = NULL;
	    const char *client_name = NULL;
	    const char *target = NULL; 
	    remote_fencing_op_t *relay_op = NULL; 
	
	    if (dev) { 
	        target = crm_element_value(dev, F_STONITH_TARGET); 
	    }
	
	    relay_op_id = crm_element_value(request, F_STONITH_REMOTE_OP_ID_RELAY);
	    op_id = crm_element_value(request, F_STONITH_REMOTE_OP_ID);
	    client_name = crm_element_value(request, F_STONITH_CLIENTNAME);
	
	    /* Delete RELAY operation. */
	    if (relay_op_id && target && pcmk__str_eq(target, stonith_our_uname, pcmk__str_casei)) {
	        relay_op = g_hash_table_lookup(stonith_remote_op_list, relay_op_id);
	
	        if (relay_op) {
	            GHashTableIter iter;
	            remote_fencing_op_t *list_op = NULL; 
	            g_hash_table_iter_init(&iter, stonith_remote_op_list);
	
	            /* If the operation to be deleted is registered as a duplicate, delete the registration. */
	            while (g_hash_table_iter_next(&iter, NULL, (void **)&list_op)) {
	                GList *dup_iter = NULL;
	                if (list_op != relay_op) {
	                    for (dup_iter = list_op->duplicates; dup_iter != NULL; dup_iter = dup_iter->next) {
	                        remote_fencing_op_t *other = dup_iter->data;
	                        if (other == relay_op) {
	                            other->duplicates = g_list_remove(other->duplicates, relay_op);
	                            break;
	                        }
	                    }
	                }
	            }
	            crm_debug("Deleting relay op %s ('%s'%s%s for %s), "
	                      "replaced by op %s ('%s'%s%s for %s)",
	                      relay_op->id, relay_op->action,
	                      (relay_op->target == NULL)? "" : " targeting ",
	                      pcmk__s(relay_op->target, ""),
	                      relay_op->client_name, op_id, relay_op->action,
	                      (target == NULL)? "" : " targeting ", pcmk__s(target, ""),
	                      client_name);
	
	            g_hash_table_remove(stonith_remote_op_list, relay_op_id);
	        }
	    }
	}
	
	/*!
	 * \internal
	 * \brief Check whether an API request was sent by a privileged user
	 *
	 * API commands related to fencing configuration may be done only by privileged
	 * IPC users (i.e. root or hacluster), because all other users should go through
	 * the CIB to have ACLs applied. If no client was given, this is a peer request,
	 * which is always allowed.
	 *
	 * \param[in] c   IPC client that sent request (or NULL if sent by CPG peer)
	 * \param[in] op  Requested API operation (for logging only)
	 *
	 * \return true if sender is peer or privileged client, otherwise false
	 */
	static inline bool
	is_privileged(const pcmk__client_t *c, const char *op)
	{
	    if ((c == NULL) || pcmk_is_set(c->flags, pcmk__client_privileged)) {
	        return true;
	    } else {
	        crm_warn("Rejecting IPC request '%s' from unprivileged client %s",
	                 pcmk__s(op, ""), pcmk__client_name(c));
	        return false;
	    }
	}
	
	// CRM_OP_REGISTER
	static xmlNode *
	handle_register_request(pcmk__request_t *request)
	{
	    xmlNode *reply = create_xml_node(NULL, "reply");
	
	    CRM_ASSERT(request->ipc_client != NULL);
	    crm_xml_add(reply, F_STONITH_OPERATION, CRM_OP_REGISTER);
	    crm_xml_add(reply, F_STONITH_CLIENTID, request->ipc_client->id);
	    pcmk__set_result(&request->result, CRM_EX_OK, PCMK_EXEC_DONE, NULL);
	    pcmk__set_request_flags(request, pcmk__request_reuse_options);
	    return reply;
	}
	
	// STONITH_OP_EXEC
	static xmlNode *
	handle_agent_request(pcmk__request_t *request)
	{
	    execute_agent_action(request->xml, &request->result);
	    if (request->result.execution_status == PCMK_EXEC_PENDING) {
	        return NULL;
	    }
	    return fenced_construct_reply(request->xml, NULL, &request->result);
	}
	
	// STONITH_OP_TIMEOUT_UPDATE
	static xmlNode *
	handle_update_timeout_request(pcmk__request_t *request)
	{
	    const char *call_id = crm_element_value(request->xml, F_STONITH_CALLID);
	    const char *client_id = crm_element_value(request->xml, F_STONITH_CLIENTID);
	    int op_timeout = 0;
	
	    crm_element_value_int(request->xml, F_STONITH_TIMEOUT, &op_timeout);
	    do_stonith_async_timeout_update(client_id, call_id, op_timeout);
	    pcmk__set_result(&request->result, CRM_EX_OK, PCMK_EXEC_DONE, NULL);
	    return NULL;
	}
	
	// STONITH_OP_QUERY
	static xmlNode *
	handle_query_request(pcmk__request_t *request)
	{
	    int timeout = 0;
	    xmlNode *dev = NULL;
	    const char *action = NULL;
	    const char *target = NULL;
	    const char *client_id = crm_element_value(request->xml, F_STONITH_CLIENTID);
	    struct st_query_data *query = NULL;
	
	    if (request->peer != NULL) {
	        // Record it for the future notification
	        create_remote_stonith_op(client_id, request->xml, TRUE);
	    }
	
	    /* Delete the DC node RELAY operation. */
	    remove_relay_op(request->xml);
	
	    pcmk__set_result(&request->result, CRM_EX_OK, PCMK_EXEC_DONE, NULL);
	
	    dev = get_xpath_object("//@" F_STONITH_ACTION, request->xml, LOG_NEVER);
	    if (dev != NULL) {
	        const char *device = crm_element_value(dev, F_STONITH_DEVICE);
	
	        if (pcmk__str_eq(device, "manual_ack", pcmk__str_casei)) {
	            return NULL; // No query or reply necessary
	        }
	        target = crm_element_value(dev, F_STONITH_TARGET);
	        action = crm_element_value(dev, F_STONITH_ACTION);
	    }
	
	    crm_log_xml_trace(request->xml, "Query");
	
	    query = calloc(1, sizeof(struct st_query_data));
	    CRM_ASSERT(query != NULL);
	
	    query->reply = fenced_construct_reply(request->xml, NULL, &request->result);
	    pcmk__str_update(&query->remote_peer, request->peer);
	    pcmk__str_update(&query->client_id, client_id);
	    pcmk__str_update(&query->target, target);
	    pcmk__str_update(&query->action, action);
	    query->call_options = request->call_options;
	
	    crm_element_value_int(request->xml, F_STONITH_TIMEOUT, &timeout);
	    get_capable_devices(target, action, timeout,
	                        pcmk_is_set(query->call_options, st_opt_allow_suicide),
	                        query, stonith_query_capable_device_cb, st_device_supports_none);
	    return NULL;
	}
	
	// T_STONITH_NOTIFY
	static xmlNode *
	handle_notify_request(pcmk__request_t *request)
	{
	    const char *flag_name = NULL;
	
	    CRM_ASSERT(request->ipc_client != NULL);
	    flag_name = crm_element_value(request->xml, F_STONITH_NOTIFY_ACTIVATE);
	    if (flag_name != NULL) {
	        crm_debug("Enabling %s callbacks for client %s",
	                  flag_name, pcmk__request_origin(request));
	        pcmk__set_client_flags(request->ipc_client, get_stonith_flag(flag_name));
	    }
	
	    flag_name = crm_element_value(request->xml, F_STONITH_NOTIFY_DEACTIVATE);
	    if (flag_name != NULL) {
	        crm_debug("Disabling %s callbacks for client %s",
	                  flag_name, pcmk__request_origin(request));
	        pcmk__clear_client_flags(request->ipc_client,
	                                 get_stonith_flag(flag_name));
	    }
	
	    pcmk__set_result(&request->result, CRM_EX_OK, PCMK_EXEC_DONE, NULL);
	    pcmk__set_request_flags(request, pcmk__request_reuse_options);
	
	    return pcmk__ipc_create_ack(request->ipc_flags, "ack", NULL, CRM_EX_OK);
	}
	
	// STONITH_OP_RELAY
	static xmlNode *
	handle_relay_request(pcmk__request_t *request)
	{
	    xmlNode *dev = get_xpath_object("//@" F_STONITH_TARGET, request->xml,
	                                    LOG_TRACE);
	
	    crm_notice("Received forwarded fencing request from "
	               "%s %s to fence (%s) peer %s",
	               pcmk__request_origin_type(request),
	               pcmk__request_origin(request),
	               crm_element_value(dev, F_STONITH_ACTION),
	               crm_element_value(dev, F_STONITH_TARGET));
	
	    if (initiate_remote_stonith_op(NULL, request->xml, FALSE) == NULL) {
	        fenced_set_protocol_error(&request->result);
	        return fenced_construct_reply(request->xml, NULL, &request->result);
	    }
	
	    pcmk__set_result(&request->result, CRM_EX_OK, PCMK_EXEC_PENDING, NULL);
	    return NULL;
	}
	
	// STONITH_OP_FENCE
	static xmlNode *
	handle_fence_request(pcmk__request_t *request)
	{
	    if ((request->peer != NULL) || stand_alone) {
	        fence_locally(request->xml, &request->result);
	
	    } else if (pcmk_is_set(request->call_options, st_opt_manual_ack)) {
	        switch (fenced_handle_manual_confirmation(request->ipc_client,
	                                                  request->xml)) {
	            case pcmk_rc_ok:
	                pcmk__set_result(&request->result, CRM_EX_OK, PCMK_EXEC_DONE,
	                                 NULL);
	                break;
	            case EINPROGRESS:
	                pcmk__set_result(&request->result, CRM_EX_OK, PCMK_EXEC_PENDING,
	                                 NULL);
	                break;
	            default:
	                fenced_set_protocol_error(&request->result);
	                break;
	        }
	
	    } else {
	        const char *alternate_host = NULL;
	        xmlNode *dev = get_xpath_object("//@" F_STONITH_TARGET, request->xml,
	                                        LOG_TRACE);
	        const char *target = crm_element_value(dev, F_STONITH_TARGET);
	        const char *action = crm_element_value(dev, F_STONITH_ACTION);
	        const char *device = crm_element_value(dev, F_STONITH_DEVICE);
	
	        if (request->ipc_client != NULL) {
	            int tolerance = 0;
	
	            crm_notice("Client %s wants to fence (%s) %s using %s",
	                       pcmk__request_origin(request), action,
	                       target, (device? device : "any device"));
	            crm_element_value_int(dev, F_STONITH_TOLERANCE, &tolerance);
	            if (stonith_check_fence_tolerance(tolerance, target, action)) {
	                pcmk__set_result(&request->result, CRM_EX_OK, PCMK_EXEC_DONE,
	                                 NULL);
	                return fenced_construct_reply(request->xml, NULL,
	                                              &request->result);
	            }
	            alternate_host = check_alternate_host(target);
	
	        } else {
	            crm_notice("Peer %s wants to fence (%s) '%s' with device '%s'",
	                       request->peer, action, target,
	                       (device == NULL)? "(any)" : device);
	        }
	
	        if (alternate_host != NULL) {
	            const char *client_id = NULL;
	            remote_fencing_op_t *op = NULL;
	
	            if (request->ipc_client->id == 0) {
	                client_id = crm_element_value(request->xml, F_STONITH_CLIENTID);
	            } else {
	                client_id = request->ipc_client->id;
	            }
	
	            /* Create a duplicate fencing operation to relay with the client ID.
	             * When a query response is received, this operation should be
	             * deleted to avoid keeping the duplicate around.
	             */
	            op = create_remote_stonith_op(client_id, request->xml, FALSE);
	
	            crm_xml_add(request->xml, F_STONITH_OPERATION, STONITH_OP_RELAY);
	            crm_xml_add(request->xml, F_STONITH_CLIENTID,
	                        request->ipc_client->id);
	            crm_xml_add(request->xml, F_STONITH_REMOTE_OP_ID, op->id);
	            send_cluster_message(crm_get_peer(0, alternate_host),
	                                 crm_msg_stonith_ng, request->xml, FALSE);
	            pcmk__set_result(&request->result, CRM_EX_OK, PCMK_EXEC_PENDING,
	                             NULL);
	
	        } else if (initiate_remote_stonith_op(request->ipc_client, request->xml,
	                                              FALSE) == NULL) {
	            fenced_set_protocol_error(&request->result);
	
	        } else {
	            pcmk__set_result(&request->result, CRM_EX_OK, PCMK_EXEC_PENDING,
	                             NULL);
	        }
	    }
	
	    if (request->result.execution_status == PCMK_EXEC_PENDING) {
	        return NULL;
	    }
	    return fenced_construct_reply(request->xml, NULL, &request->result);
	}
	
	// STONITH_OP_FENCE_HISTORY
	static xmlNode *
	handle_history_request(pcmk__request_t *request)
	{
	    xmlNode *reply = NULL;
	    xmlNode *data = NULL;
	
	    stonith_fence_history(request->xml, &data, request->peer,
	                          request->call_options);
	    pcmk__set_result(&request->result, CRM_EX_OK, PCMK_EXEC_DONE, NULL);
	    if (!pcmk_is_set(request->call_options, st_opt_discard_reply)) {
	        /* When the local node broadcasts its history, it sets
	         * st_opt_discard_reply and doesn't need a reply.
	         */
	        reply = fenced_construct_reply(request->xml, data, &request->result);
	    }
	    free_xml(data);
	    return reply;
	}
	
	// STONITH_OP_DEVICE_ADD
	static xmlNode *
	handle_device_add_request(pcmk__request_t *request)
	{
	    const char *op = crm_element_value(request->xml, F_STONITH_OPERATION);
	    xmlNode *dev = get_xpath_object("//" F_STONITH_DEVICE, request->xml,
	                                    LOG_ERR);
	
	    if (is_privileged(request->ipc_client, op)) {
	        int rc = stonith_device_register(dev, FALSE);
	
	        pcmk__set_result(&request->result,
	                         ((rc == pcmk_ok)? CRM_EX_OK : CRM_EX_ERROR),
	                         stonith__legacy2status(rc),
	                         ((rc == pcmk_ok)? NULL : pcmk_strerror(rc)));
	    } else {
	        pcmk__set_result(&request->result, CRM_EX_INSUFFICIENT_PRIV,
	                         PCMK_EXEC_INVALID,
	                         "Unprivileged users must register device via CIB");
	    }
	    fenced_send_device_notification(op, &request->result,
	                                    (dev == NULL)? NULL : ID(dev));
	    return fenced_construct_reply(request->xml, NULL, &request->result);
	}
	
	// STONITH_OP_DEVICE_DEL
	static xmlNode *
	handle_device_delete_request(pcmk__request_t *request)
	{
	    xmlNode *dev = get_xpath_object("//" F_STONITH_DEVICE, request->xml,
	                                    LOG_ERR);
	    const char *device_id = crm_element_value(dev, XML_ATTR_ID);
	    const char *op = crm_element_value(request->xml, F_STONITH_OPERATION);
	
	    if (is_privileged(request->ipc_client, op)) {
	        stonith_device_remove(device_id, false);
	        pcmk__set_result(&request->result, CRM_EX_OK, PCMK_EXEC_DONE, NULL);
	    } else {
	        pcmk__set_result(&request->result, CRM_EX_INSUFFICIENT_PRIV,
	                         PCMK_EXEC_INVALID,
	                         "Unprivileged users must delete device via CIB");
	    }
	    fenced_send_device_notification(op, &request->result, device_id);
	    return fenced_construct_reply(request->xml, NULL, &request->result);
	}
	
	// STONITH_OP_LEVEL_ADD
	static xmlNode *
	handle_level_add_request(pcmk__request_t *request)
	{
	    char *desc = NULL;
	    const char *op = crm_element_value(request->xml, F_STONITH_OPERATION);
	
	    if (is_privileged(request->ipc_client, op)) {
	        fenced_register_level(request->xml, &desc, &request->result);
	    } else {
	        unpack_level_request(request->xml, NULL, NULL, NULL, &desc);
	        pcmk__set_result(&request->result, CRM_EX_INSUFFICIENT_PRIV,
	                         PCMK_EXEC_INVALID,
	                         "Unprivileged users must add level via CIB");
	    }
	    fenced_send_level_notification(op, &request->result, desc);
	    free(desc);
	    return fenced_construct_reply(request->xml, NULL, &request->result);
	}
	
	// STONITH_OP_LEVEL_DEL
	static xmlNode *
	handle_level_delete_request(pcmk__request_t *request)
	{
	    char *desc = NULL;
	    const char *op = crm_element_value(request->xml, F_STONITH_OPERATION);
	
	    if (is_privileged(request->ipc_client, op)) {
	        fenced_unregister_level(request->xml, &desc, &request->result);
	    } else {
	        unpack_level_request(request->xml, NULL, NULL, NULL, &desc);
	        pcmk__set_result(&request->result, CRM_EX_INSUFFICIENT_PRIV,
	                         PCMK_EXEC_INVALID,
	                         "Unprivileged users must delete level via CIB");
	    }
	    fenced_send_level_notification(op, &request->result, desc);
	    free(desc);
	    return fenced_construct_reply(request->xml, NULL, &request->result);
	}
	
	// CRM_OP_RM_NODE_CACHE
	static xmlNode *
	handle_cache_request(pcmk__request_t *request)
	{
	    int node_id = 0;
	    const char *name = NULL;
	
	    crm_element_value_int(request->xml, XML_ATTR_ID, &node_id);
	    name = crm_element_value(request->xml, XML_ATTR_UNAME);
	    reap_crm_member(node_id, name);
	    pcmk__set_result(&request->result, CRM_EX_OK, PCMK_EXEC_DONE, NULL);
	    return NULL;
	}
	
	static xmlNode *
	handle_unknown_request(pcmk__request_t *request)
	{
	    crm_err("Unknown IPC request %s from %s %s",
	            request->op, pcmk__request_origin_type(request),
	            pcmk__request_origin(request));
	    pcmk__format_result(&request->result, CRM_EX_PROTOCOL, PCMK_EXEC_INVALID,
	                        "Unknown IPC request type '%s' (bug?)", request->op);
	    return fenced_construct_reply(request->xml, NULL, &request->result);
	}
	
	static void
	fenced_register_handlers(void)
	{
	    pcmk__server_command_t handlers[] = {
	        { CRM_OP_REGISTER, handle_register_request },
	        { STONITH_OP_EXEC, handle_agent_request },
	        { STONITH_OP_TIMEOUT_UPDATE, handle_update_timeout_request },
	        { STONITH_OP_QUERY, handle_query_request },
	        { T_STONITH_NOTIFY, handle_notify_request },
	        { STONITH_OP_RELAY, handle_relay_request },
	        { STONITH_OP_FENCE, handle_fence_request },
	        { STONITH_OP_FENCE_HISTORY, handle_history_request },
	        { STONITH_OP_DEVICE_ADD, handle_device_add_request },
	        { STONITH_OP_DEVICE_DEL, handle_device_delete_request },
	        { STONITH_OP_LEVEL_ADD, handle_level_add_request },
	        { STONITH_OP_LEVEL_DEL, handle_level_delete_request },
	        { CRM_OP_RM_NODE_CACHE, handle_cache_request },
	        { NULL, handle_unknown_request },
	    };
	
	    fenced_handlers = pcmk__register_handlers(handlers);
	}
	
	void
	fenced_unregister_handlers(void)
	{
	    if (fenced_handlers != NULL) {
	        g_hash_table_destroy(fenced_handlers);
	        fenced_handlers = NULL;
	    }
	}
	
	static void
	handle_request(pcmk__request_t *request)
	{
	    xmlNode *reply = NULL;
	    const char *reason = NULL;
	
	    if (fenced_handlers == NULL) {
	        fenced_register_handlers();
	    }
	    reply = pcmk__process_request(request, fenced_handlers);
	    if (reply != NULL) {
	        if (pcmk_is_set(request->flags, pcmk__request_reuse_options)
	            && (request->ipc_client != NULL)) {
	            /* Certain IPC-only commands must reuse the call options from the
	             * original request rather than the ones set by stonith_send_reply()
	             * -> do_local_reply().
	             */
	            pcmk__ipc_send_xml(request->ipc_client, request->ipc_id, reply,
	                               request->ipc_flags);
	            request->ipc_client->request_id = 0;
	        } else {
	            stonith_send_reply(reply, request->call_options,
	                               request->peer, request->ipc_client);
	        }
	        free_xml(reply);
	    }
	
	    reason = request->result.exit_reason;
	    crm_debug("Processed %s request from %s %s: %s%s%s%s",
	              request->op, pcmk__request_origin_type(request),
	              pcmk__request_origin(request),
	              pcmk_exec_status_str(request->result.execution_status),
	              (reason == NULL)? "" : " (",
	              (reason == NULL)? "" : reason,
	              (reason == NULL)? "" : ")");
	}
	
	static void
	handle_reply(pcmk__client_t *client, xmlNode *request, const char *remote_peer)
	{
	    // Copy, because request might be freed before we want to log this
	    char *op = crm_element_value_copy(request, F_STONITH_OPERATION);
	
	    if (pcmk__str_eq(op, STONITH_OP_QUERY, pcmk__str_none)) {
	        process_remote_stonith_query(request);
	    } else if (pcmk__str_any_of(op, T_STONITH_NOTIFY, STONITH_OP_FENCE, NULL)) {
	        fenced_process_fencing_reply(request);
	    } else {
	        crm_err("Ignoring unknown %s reply from %s %s",
	                pcmk__s(op, "untyped"), ((client == NULL)? "peer" : "client"),
	                ((client == NULL)? remote_peer : pcmk__client_name(client)));
	        crm_log_xml_warn(request, "UnknownOp");
	        free(op);
	        return;
	    }
	    crm_debug("Processed %s reply from %s %s",
	              op, ((client == NULL)? "peer" : "client"),
	              ((client == NULL)? remote_peer : pcmk__client_name(client)));
	    free(op);
	}
	
	/*!
	 * \internal
	 * \brief Handle a message from an IPC client or CPG peer
	 *
	 * \param[in,out] client      If not NULL, IPC client that sent message
	 * \param[in]     id          If from IPC client, IPC message ID
	 * \param[in]     flags       Message flags
	 * \param[in,out] message     Message XML
	 * \param[in]     remote_peer If not NULL, CPG peer that sent message
	 */
	void
	stonith_command(pcmk__client_t *client, uint32_t id, uint32_t flags,
	                xmlNode *message, const char *remote_peer)
	{
	    int call_options = st_opt_none;
	    bool is_reply = false;
	
	    CRM_CHECK(message != NULL, return);
	
	    if (get_xpath_object("//" T_STONITH_REPLY, message, LOG_NEVER) != NULL) {
	        is_reply = true;
	    }
	    crm_element_value_int(message, F_STONITH_CALLOPTS, &call_options);
	    crm_debug("Processing %ssynchronous %s %s %u from %s %s",
	              pcmk_is_set(call_options, st_opt_sync_call)? "" : "a",
	              crm_element_value(message, F_STONITH_OPERATION),
	              (is_reply? "reply" : "request"), id,
	              ((client == NULL)? "peer" : "client"),
	              ((client == NULL)? remote_peer : pcmk__client_name(client)));
	
	    if (pcmk_is_set(call_options, st_opt_sync_call)) {
	        CRM_ASSERT(client == NULL || client->request_id == id);
	    }
	
	    if (is_reply) {
	        handle_reply(client, message, remote_peer);
	    } else {
	        pcmk__request_t request = {
	            .ipc_client     = client,
	            .ipc_id         = id,
	            .ipc_flags      = flags,
	            .peer           = remote_peer,
	            .xml            = message,
	            .call_options   = call_options,
	            .result         = PCMK__UNKNOWN_RESULT,
	        };
	
	        request.op = crm_element_value_copy(request.xml, F_STONITH_OPERATION);
	        CRM_CHECK(request.op != NULL, return);
	
	        if (pcmk_is_set(request.call_options, st_opt_sync_call)) {
	            pcmk__set_request_flags(&request, pcmk__request_sync);
	        }
	
	        handle_request(&request);
	        pcmk__reset_request(&request);
	    }
	}