/*
	 * Copyright (C) 2010 Red Hat, Inc.
	 *
	 * Author: Angus Salkeld <asalkeld@redhat.com>
	 *
	 * This file is part of libqb.
	 *
	 * libqb is free software: you can redistribute it and/or modify
	 * it under the terms of the GNU Lesser General Public License as published by
	 * the Free Software Foundation, either version 2.1 of the License, or
	 * (at your option) any later version.
	 *
	 * libqb is distributed in the hope that it will be useful,
	 * but WITHOUT ANY WARRANTY; without even the implied warranty of
	 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	 * GNU Lesser General Public License for more details.
	 *
	 * You should have received a copy of the GNU Lesser General Public License
	 * along with libqb.  If not, see <http://www.gnu.org/licenses/>.
	 */
	#include "os_base.h"
	#include <poll.h>
	
	#include "util_int.h"
	#include "ipc_int.h"
	#include <qb/qbdefs.h>
	#include <qb/qbatomic.h>
	#include <qb/qbipcs.h>
	
	static void qb_ipcs_flowcontrol_set(struct qb_ipcs_connection *c,
					    int32_t fc_enable);
	static int32_t
	new_event_notification(struct qb_ipcs_connection * c);
	
	
	qb_ipcs_service_t *
	qb_ipcs_create(const char *name,
		       int32_t service_id,
		       enum qb_ipc_type type, struct qb_ipcs_service_handlers *handlers)
	{
		struct qb_ipcs_service *s;
	
		s = calloc(1, sizeof(struct qb_ipcs_service));
		if (s == NULL) {
			return NULL;
		}
		if (type == QB_IPC_NATIVE) {
	#ifdef DISABLE_IPC_SHM
			s->type = QB_IPC_SOCKET;
	#else
			s->type = QB_IPC_SHM;
	#endif /* DISABLE_IPC_SHM */
		} else {
			s->type = type;
		}
	
		s->pid = getpid();
		s->needs_sock_for_poll = QB_FALSE;
		s->poll_priority = QB_LOOP_MED;
	
		/* Initial alloc ref */
		qb_ipcs_ref(s);
	
		s->service_id = service_id;
		(void)strlcpy(s->name, name, NAME_MAX);
	
		s->serv_fns.connection_accept = handlers->connection_accept;
		s->serv_fns.connection_created = handlers->connection_created;
		s->serv_fns.msg_process = handlers->msg_process;
		s->serv_fns.connection_closed = handlers->connection_closed;
		s->serv_fns.connection_destroyed = handlers->connection_destroyed;
	
		qb_list_init(&s->connections);
	
		return s;
	}
	
	void
	qb_ipcs_poll_handlers_set(struct qb_ipcs_service *s,
				  struct qb_ipcs_poll_handlers *handlers)
	{
		s->poll_fns.job_add = handlers->job_add;
		s->poll_fns.dispatch_add = handlers->dispatch_add;
		s->poll_fns.dispatch_mod = handlers->dispatch_mod;
		s->poll_fns.dispatch_del = handlers->dispatch_del;
	}
	
	void
	qb_ipcs_service_context_set(qb_ipcs_service_t* s,
				    void *context)
	{
		s->context = context;
	}
	
	void *
	qb_ipcs_service_context_get(qb_ipcs_service_t* s)
	{
		return s->context;
	}
	
	int32_t
	qb_ipcs_run(struct qb_ipcs_service *s)
	{
		int32_t res = 0;
	
		if (s->poll_fns.dispatch_add == NULL ||
		    s->poll_fns.dispatch_mod == NULL ||
		    s->poll_fns.dispatch_del == NULL) {
	
			res = -EINVAL;
			goto run_cleanup;
		}
	
		switch (s->type) {
		case QB_IPC_SOCKET:
			qb_ipcs_us_init((struct qb_ipcs_service *)s);
			break;
		case QB_IPC_SHM:
	#ifdef DISABLE_IPC_SHM
			res = -ENOTSUP;
	#else
			qb_ipcs_shm_init((struct qb_ipcs_service *)s);
	#endif /* DISABLE_IPC_SHM */
			break;
		case QB_IPC_POSIX_MQ:
		case QB_IPC_SYSV_MQ:
			res = -ENOTSUP;
			break;
		default:
			res = -EINVAL;
			break;
		}
	
		if (res == 0) {
			res = qb_ipcs_us_publish(s);
			if (res < 0) {
				(void)qb_ipcs_us_withdraw(s);
				goto run_cleanup;
			}
		}
	
	run_cleanup:
		if (res < 0) {
			/* Failed to run services, removing initial alloc reference. */
			qb_ipcs_unref(s);
		}
	
		return res;
	}
	
	static int32_t
	_modify_dispatch_descriptor_(struct qb_ipcs_connection *c)
	{
		qb_ipcs_dispatch_mod_fn disp_mod = c->service->poll_fns.dispatch_mod;
	
		if (c->service->type == QB_IPC_SOCKET) {
			return disp_mod(c->service->poll_priority,
					c->event.u.us.sock,
					c->poll_events, c,
					qb_ipcs_dispatch_connection_request);
		} else {
			return disp_mod(c->service->poll_priority,
					c->setup.u.us.sock,
					c->poll_events, c,
					qb_ipcs_dispatch_connection_request);
		}
		return -EINVAL;
	}
	
	void
	qb_ipcs_request_rate_limit(struct qb_ipcs_service *s,
				   enum qb_ipcs_rate_limit rl)
	{
		struct qb_ipcs_connection *c;
		enum qb_loop_priority old_p = s->poll_priority;
		struct qb_list_head *pos;
		struct qb_list_head *n;
	
		switch (rl) {
		case QB_IPCS_RATE_FAST:
			s->poll_priority = QB_LOOP_HIGH;
			break;
		case QB_IPCS_RATE_SLOW:
		case QB_IPCS_RATE_OFF:
		case QB_IPCS_RATE_OFF_2:
			s->poll_priority = QB_LOOP_LOW;
			break;
		default:
		case QB_IPCS_RATE_NORMAL:
			s->poll_priority = QB_LOOP_MED;
			break;
		}
	
		qb_list_for_each_safe(pos, n, &s->connections) {
	
			c = qb_list_entry(pos, struct qb_ipcs_connection, list);
			qb_ipcs_connection_ref(c);
	
			if (rl == QB_IPCS_RATE_OFF) {
				qb_ipcs_flowcontrol_set(c, 1);
			} else if (rl == QB_IPCS_RATE_OFF_2) {
				qb_ipcs_flowcontrol_set(c, 2);
			} else {
				qb_ipcs_flowcontrol_set(c, QB_FALSE);
			}
			if (old_p != s->poll_priority) {
				(void)_modify_dispatch_descriptor_(c);
			}
			qb_ipcs_connection_unref(c);
		}
	}
	
	void
	qb_ipcs_ref(struct qb_ipcs_service *s)
	{
		qb_atomic_int_inc(&s->ref_count);
	}
	
	void
	qb_ipcs_unref(struct qb_ipcs_service *s)
	{
		int32_t free_it;
	
		assert(s->ref_count > 0);
		free_it = qb_atomic_int_dec_and_test(&s->ref_count);
		if (free_it) {
			qb_util_log(LOG_DEBUG, "%s() - destroying", __func__);
			free(s);
		}
	}
	
	void
	qb_ipcs_destroy(struct qb_ipcs_service *s)
	{
		struct qb_ipcs_connection *c = NULL;
		struct qb_list_head *pos;
		struct qb_list_head *n;
	
		if (s == NULL) {
			return;
		}
		qb_list_for_each_safe(pos, n, &s->connections) {
			c = qb_list_entry(pos, struct qb_ipcs_connection, list);
			if (c == NULL) {
				continue;
			}
			qb_ipcs_disconnect(c);
		}
		(void)qb_ipcs_us_withdraw(s);
	
		/* service destroyed, remove initial alloc ref */
		qb_ipcs_unref(s);
	}
	
	/*
	 * connection API
	 */
	static struct qb_ipc_one_way *
	_event_sock_one_way_get(struct qb_ipcs_connection * c)
	{
		if (c->service->needs_sock_for_poll) {
			return &c->setup;
		}
		if (c->event.type == QB_IPC_SOCKET) {
			return &c->event;
		}
		return NULL;
	}
	
	static struct qb_ipc_one_way *
	_response_sock_one_way_get(struct qb_ipcs_connection * c)
	{
		if (c->service->needs_sock_for_poll) {
			return &c->setup;
		}
		if (c->response.type == QB_IPC_SOCKET) {
			return &c->response;
		}
		return NULL;
	}
	
	ssize_t
	qb_ipcs_response_send(struct qb_ipcs_connection *c, const void *data,
			      size_t size)
	{
		ssize_t res;
	
		if (c == NULL) {
			return -EINVAL;
		}
		qb_ipcs_connection_ref(c);
		res = c->service->funcs.send(&c->response, data, size);
		if (res == size) {
			c->stats.responses++;
		} else if (res == -EAGAIN || res == -ETIMEDOUT) {
			struct qb_ipc_one_way *ow = _response_sock_one_way_get(c);
			if (ow) {
				ssize_t res2 = qb_ipc_us_ready(ow, &c->setup, 0, POLLOUT);
				if (res2 < 0) {
					res = res2;
				}
			}
			c->stats.send_retries++;
		}
		qb_ipcs_connection_unref(c);
	
		return res;
	}
	
	ssize_t
	qb_ipcs_response_sendv(struct qb_ipcs_connection * c, const struct iovec * iov,
			       size_t iov_len)
	{
		ssize_t res;
	
		if (c == NULL) {
			return -EINVAL;
		}
		qb_ipcs_connection_ref(c);
		res = c->service->funcs.sendv(&c->response, iov, iov_len);
		if (res > 0) {
			c->stats.responses++;
		} else if (res == -EAGAIN || res == -ETIMEDOUT) {
			struct qb_ipc_one_way *ow = _response_sock_one_way_get(c);
			if (ow) {
				ssize_t res2 = qb_ipc_us_ready(ow, &c->setup, 0, POLLOUT);
				if (res2 < 0) {
					res = res2;
				}
			}
			c->stats.send_retries++;
		}
		qb_ipcs_connection_unref(c);
	
		return res;
	}
	
	static int32_t
	resend_event_notifications(struct qb_ipcs_connection *c)
	{
		ssize_t res = 0;
	
		if (!c->service->needs_sock_for_poll) {
			return res;
		}
	
		if (c->outstanding_notifiers > 0) {
			res = qb_ipc_us_send(&c->setup, c->receive_buf,
					     c->outstanding_notifiers);
		}
		if (res > 0) {
			c->outstanding_notifiers -= res;
		}
	
		assert(c->outstanding_notifiers >= 0);
		if (c->outstanding_notifiers == 0) {
			c->poll_events = POLLIN | POLLPRI | POLLNVAL;
			(void)_modify_dispatch_descriptor_(c);
		}
		return res;
	}
	
	static int32_t
	new_event_notification(struct qb_ipcs_connection * c)
	{
		ssize_t res = 0;
	
		if (!c->service->needs_sock_for_poll) {
			return res;
		}
	
		assert(c->outstanding_notifiers >= 0);
		if (c->outstanding_notifiers > 0) {
			c->outstanding_notifiers++;
			res = resend_event_notifications(c);
		} else {
			res = qb_ipc_us_send(&c->setup, &c->outstanding_notifiers, 1);
			if (res == -EAGAIN) {
				/*
				 * notify the client later, when we can.
				 */
				c->outstanding_notifiers++;
				c->poll_events = POLLOUT | POLLIN | POLLPRI | POLLNVAL;
				(void)_modify_dispatch_descriptor_(c);
			}
		}
		return res;
	}
	
	ssize_t
	qb_ipcs_event_send(struct qb_ipcs_connection * c, const void *data, size_t size)
	{
		ssize_t res;
		ssize_t resn;
	
		if (c == NULL) {
			return -EINVAL;
		} else if (size > c->event.max_msg_size) {
			return -EMSGSIZE;
		}
	
		qb_ipcs_connection_ref(c);
		res = c->service->funcs.send(&c->event, data, size);
		if (res == size) {
			c->stats.events++;
			resn = new_event_notification(c);
			if (resn < 0 && resn != -EAGAIN && resn != -ENOBUFS) {
				errno = -resn;
				qb_util_perror(LOG_DEBUG,
					       "new_event_notification (%s)",
					       c->description);
				res = resn;
			}
		} else if (res == -EAGAIN || res == -ETIMEDOUT) {
			struct qb_ipc_one_way *ow = _event_sock_one_way_get(c);
	
			if (c->outstanding_notifiers > 0) {

				resn = resend_event_notifications(c);
			}
			if (ow) {

				resn = qb_ipc_us_ready(ow, &c->setup, 0, POLLOUT);
				if (resn < 0) {
					res = resn;
				}
			}
			c->stats.send_retries++;
		}
	
		qb_ipcs_connection_unref(c);
		return res;
	}
	
	ssize_t
	qb_ipcs_event_sendv(struct qb_ipcs_connection * c,
			    const struct iovec * iov, size_t iov_len)
	{
		ssize_t res;
		ssize_t resn;
	
		if (c == NULL) {
			return -EINVAL;
		}
		qb_ipcs_connection_ref(c);
	
		res = c->service->funcs.sendv(&c->event, iov, iov_len);
		if (res > 0) {
			c->stats.events++;
			resn = new_event_notification(c);
			if (resn < 0 && resn != -EAGAIN) {
				errno = -resn;
				qb_util_perror(LOG_DEBUG,
					       "new_event_notification (%s)",
					       c->description);
				res = resn;
			}
		} else if (res == -EAGAIN || res == -ETIMEDOUT) {
			struct qb_ipc_one_way *ow = _event_sock_one_way_get(c);
	
			if (c->outstanding_notifiers > 0) {
				resn = resend_event_notifications(c);
			}
			if (ow) {
				resn = qb_ipc_us_ready(ow, &c->setup, 0, POLLOUT);
				if (resn < 0) {
					res = resn;
				}
			}
			c->stats.send_retries++;
		}
	
		qb_ipcs_connection_unref(c);
		return res;
	}
	
	qb_ipcs_connection_t *
	qb_ipcs_connection_first_get(struct qb_ipcs_service * s)
	{
		struct qb_ipcs_connection *c;
	
		if (qb_list_empty(&s->connections)) {
			return NULL;
		}
	
		c = qb_list_first_entry(&s->connections, struct qb_ipcs_connection,
					list);
		qb_ipcs_connection_ref(c);
	
		return c;
	}
	
	qb_ipcs_connection_t *
	qb_ipcs_connection_next_get(struct qb_ipcs_service * s,
				    struct qb_ipcs_connection * current)
	{
		struct qb_ipcs_connection *c;
	
		if (current == NULL ||
		    qb_list_is_last(&current->list, &s->connections)) {
			return NULL;
		}
	
		c = qb_list_first_entry(&current->list, struct qb_ipcs_connection,
					list);
		qb_ipcs_connection_ref(c);
	
		return c;
	}
	
	int32_t
	qb_ipcs_service_id_get(struct qb_ipcs_connection * c)
	{
		if (c == NULL) {
			return -EINVAL;
		}
		return c->service->service_id;
	}
	
	struct qb_ipcs_connection *
	qb_ipcs_connection_alloc(struct qb_ipcs_service *s)
	{
		struct qb_ipcs_connection *c =
		    calloc(1, sizeof(struct qb_ipcs_connection));
	
		if (c == NULL) {
			return NULL;
		}
	
		c->pid = 0;
		c->euid = -1;
		c->egid = -1;
		c->receive_buf = NULL;
		c->context = NULL;
		c->fc_enabled = QB_FALSE;
		c->state = QB_IPCS_CONNECTION_INACTIVE;
		c->poll_events = POLLIN | POLLPRI | POLLNVAL;
	
		c->setup.type = s->type;
		c->request.type = s->type;
		c->response.type = s->type;
		c->event.type = s->type;
		(void)strlcpy(c->description, "not set yet", CONNECTION_DESCRIPTION);
	
		/* initial alloc ref */
		qb_ipcs_connection_ref(c);
	
		/*
		 * The connection makes use of the service object. Give the connection
		 * a reference to the service so we know the service can never be destroyed
		 * until the connection is done with it.
		 */
		qb_ipcs_ref(s);
		c->service = s;
		qb_list_init(&c->list);
	
		return c;
	}
	
	void
	qb_ipcs_connection_ref(struct qb_ipcs_connection *c)
	{
		if (c) {
			qb_atomic_int_inc(&c->refcount);
		}
	}
	
	void
	qb_ipcs_connection_unref(struct qb_ipcs_connection *c)
	{
		int32_t free_it;
	
		if (c == NULL) {
			return;
		}
		if (c->refcount < 1) {
			qb_util_log(LOG_ERR, "ref:%d state:%d (%s)",
				    c->refcount, c->state, c->description);
			assert(0);
		}
		free_it = qb_atomic_int_dec_and_test(&c->refcount);
		if (free_it) {
			qb_list_del(&c->list);
			if (c->service->serv_fns.connection_destroyed) {
				c->service->serv_fns.connection_destroyed(c);
			}
			c->service->funcs.disconnect(c);
			/* Let go of the connection's reference to the service */
			qb_ipcs_unref(c->service);
			free(c->receive_buf);
			free(c);
		}
	}
	
	void
	qb_ipcs_disconnect(struct qb_ipcs_connection *c)
	{
		int32_t res = 0;
		qb_loop_job_dispatch_fn rerun_job;
	
		if (c == NULL) {
			return;
		}
		qb_util_log(LOG_DEBUG, "%s(%s) state:%d",
			    __func__, c->description, c->state);
	
		if (c->state == QB_IPCS_CONNECTION_ACTIVE) {
			c->service->funcs.disconnect(c);
			c->state = QB_IPCS_CONNECTION_INACTIVE;
			c->service->stats.closed_connections++;
	
			/* This removes the initial alloc ref */
			qb_ipcs_connection_unref(c);
	
			/* return early as it's an incomplete connection.
			 */
			return;
		}
		if (c->state == QB_IPCS_CONNECTION_ESTABLISHED) {
			c->service->funcs.disconnect(c);
			c->state = QB_IPCS_CONNECTION_SHUTTING_DOWN;
			c->service->stats.active_connections--;
			c->service->stats.closed_connections++;
		}
		if (c->state == QB_IPCS_CONNECTION_SHUTTING_DOWN) {
			int scheduled_retry = 0;
			res = 0;
			if (c->service->serv_fns.connection_closed) {
				res = c->service->serv_fns.connection_closed(c);
			}
			if (res != 0) {
				/* OK, so they want the connection_closed
				 * function re-run */
				rerun_job =
				    (qb_loop_job_dispatch_fn) qb_ipcs_disconnect;
				res = c->service->poll_fns.job_add(QB_LOOP_LOW,
								   c, rerun_job);
				if (res == 0) {
					/* this function is going to be called again.
					 * so hold off on the unref */
					scheduled_retry = 1;
				}
			}
			remove_tempdir(c->description);
			if (scheduled_retry == 0) {
				/* This removes the initial alloc ref */
				qb_ipcs_connection_unref(c);
			}
		}
	
	}
	
	static void
	qb_ipcs_flowcontrol_set(struct qb_ipcs_connection *c, int32_t fc_enable)
	{
		if (c == NULL) {
			return;
		}
		if (c->fc_enabled != fc_enable) {
			c->service->funcs.fc_set(&c->request, fc_enable);
			c->fc_enabled = fc_enable;
			c->stats.flow_control_state = fc_enable;
			c->stats.flow_control_count++;
		}
	}
	
	static int32_t
	_process_request_(struct qb_ipcs_connection *c, int32_t ms_timeout)
	{
		int32_t res = 0;
		ssize_t size;
		struct qb_ipc_request_header *hdr;
	
		if (c->service->funcs.peek && c->service->funcs.reclaim) {
			size = c->service->funcs.peek(&c->request, (void **)&hdr,
						      ms_timeout);
		} else {
			hdr = c->receive_buf;
			size = c->service->funcs.recv(&c->request,
						      hdr,
						      c->request.max_msg_size,
						      ms_timeout);
		}
		if (size < 0) {
			if (size != -EAGAIN && size != -ETIMEDOUT) {
				qb_util_perror(LOG_DEBUG,
					       "recv from client connection failed (%s)",
					       c->description);
			} else {
				c->stats.recv_retries++;
			}
			res = size;
			goto cleanup;
		} else if (size == 0 || hdr->id == QB_IPC_MSG_DISCONNECT) {
			qb_util_log(LOG_DEBUG, "client requesting a disconnect (%s)",
				    c->description);
			res = -ESHUTDOWN;
			goto cleanup;
		} else {
			/* Validate message size to prevent integer overflow attacks */
			if (hdr->size <= 0 || hdr->size > c->request.max_msg_size) {
				qb_util_log(LOG_WARNING,
					    "invalid message size %d (max: %zu) from client %s",
					    hdr->size, c->request.max_msg_size, c->description);
				res = -EINVAL;
				goto cleanup;
			}
			c->stats.requests++;
			res = c->service->serv_fns.msg_process(c, hdr, hdr->size);
			/* 0 == good, negative == backoff */
			if (res < 0) {
				res = -ENOBUFS;
			} else {
				res = size;
			}
		}
	
		if (c->service->funcs.peek && c->service->funcs.reclaim) {
			c->service->funcs.reclaim(&c->request);
		}
	
	cleanup:
		return res;
	}
	
	#define IPC_REQUEST_TIMEOUT 10
	#define MAX_RECV_MSGS 50
	
	static ssize_t
	_request_q_len_get(struct qb_ipcs_connection *c)
	{
		ssize_t q_len;
		if (c->service->funcs.q_len_get) {
			q_len = c->service->funcs.q_len_get(&c->request);
			if (q_len <= 0) {
				return q_len;
			}
			if (c->service->poll_priority == QB_LOOP_MED) {
				q_len = QB_MIN(q_len, 5);
			} else if (c->service->poll_priority == QB_LOOP_LOW) {
				q_len = 1;
			} else {
				q_len = QB_MIN(q_len, MAX_RECV_MSGS);
			}
		} else {
			q_len = 1;
		}
		return q_len;
	}
	
	int32_t
	qb_ipcs_dispatch_connection_request(int32_t fd, int32_t revents, void *data)
	{
		struct qb_ipcs_connection *c = (struct qb_ipcs_connection *)data;
		char bytes[MAX_RECV_MSGS];
		int32_t res = 0;
		int32_t res2;
		int32_t recvd = 0;
		ssize_t avail;
	
		if (c == NULL) {
			res = -EINVAL;
			goto dispatch_cleanup;
		}
	
		if (revents & POLLNVAL) {
			qb_util_log(LOG_DEBUG, "NVAL conn (%s)", c->description);
			res = -EINVAL;
			goto dispatch_cleanup;
		}
		if (revents & POLLHUP) {
			qb_util_log(LOG_DEBUG, "HUP conn (%s)", c->description);
			res = -ESHUTDOWN;
			goto dispatch_cleanup;
		}
	
		if (revents & POLLOUT) {
			/* try resend events now that fd can write */
			res = resend_event_notifications(c);
			if (res < 0 && res != -EAGAIN) {
				errno = -res;
				qb_util_perror(LOG_WARNING,
					       "resend_event_notifications (%s)",
					       c->description);
			}
			/* nothing to read */
			if ((revents & POLLIN) == 0) {
				res = 0;
				goto dispatch_cleanup;
			}
		}
		if (c->fc_enabled) {
			res = 0;
			goto dispatch_cleanup;
		}
		avail = _request_q_len_get(c);
	
		if (c->service->needs_sock_for_poll && avail == 0) {
			res2 = qb_ipc_us_recv(&c->setup, bytes, 1, 0);
			if (qb_ipc_us_sock_error_is_disconnected(res2)) {
				errno = -res2;
				qb_util_perror(LOG_WARNING, "conn (%s) disconnected",
					       c->description);
				res = -ESHUTDOWN;
				goto dispatch_cleanup;
			} else {
				qb_util_log(LOG_WARNING,
					    "conn (%s) Nothing in q but got POLLIN on fd:%d (res2:%d)",
					    c->description, fd, res2);
				res = 0;
				goto dispatch_cleanup;
			}
		}
	
		do {
			res = _process_request_(c, IPC_REQUEST_TIMEOUT);
	
			if (res == -ESHUTDOWN) {
				goto dispatch_cleanup;
			}
	
			if (res > 0 || res == -ENOBUFS || res == -EINVAL) {
				recvd++;
			}
			if (res > 0) {
				avail--;
			}
		} while (avail > 0 && res > 0 && !c->fc_enabled);
	
		if (c->service->needs_sock_for_poll && recvd > 0) {
			res2 = qb_ipc_us_recv(&c->setup, bytes, recvd, -1);
			if (qb_ipc_us_sock_error_is_disconnected(res2)) {
				errno = -res2;
				qb_util_perror(LOG_ERR, "error receiving from setup sock (%s)", c->description);
	
				res = -ESHUTDOWN;
				goto dispatch_cleanup;
			}
		}
	
		res = QB_MIN(0, res);
		if (res == -EAGAIN || res == -ETIMEDOUT || res == -ENOBUFS) {
			res = 0;
		}
		if (res != 0) {
			if (res != -ENOTCONN) {
				/*
				 * Abnormal state (ENOTCONN is normal shutdown).
				 */
				errno = -res;
				qb_util_perror(LOG_ERR, "request returned error (%s)",
					       c->description);
			}
		}
	
	dispatch_cleanup:
		if (res != 0) {
			qb_ipcs_disconnect(c);
		}
		return res;
	}
	
	void
	qb_ipcs_context_set(struct qb_ipcs_connection *c, void *context)
	{
		if (c == NULL) {
			return;
		}
		c->context = context;
	}
	
	void *
	qb_ipcs_context_get(struct qb_ipcs_connection *c)
	{
		if (c == NULL) {
			return NULL;
		}
		return c->context;
	}
	
	void *
	qb_ipcs_connection_service_context_get(qb_ipcs_connection_t *c)
	{
		if (c == NULL || c->service == NULL) {
			return NULL;
		}
		return c->service->context;
	}
	
	int32_t
	qb_ipcs_connection_stats_get(qb_ipcs_connection_t * c,
				     struct qb_ipcs_connection_stats * stats,
				     int32_t clear_after_read)
	{
		if (c == NULL) {
			return -EINVAL;
		}
		memcpy(stats, &c->stats, sizeof(struct qb_ipcs_connection_stats));
		if (clear_after_read) {
			memset(&c->stats, 0, sizeof(struct qb_ipcs_connection_stats_2));
			c->stats.client_pid = c->pid;
		}
		return 0;
	}
	
	struct qb_ipcs_connection_stats_2*
	qb_ipcs_connection_stats_get_2(qb_ipcs_connection_t *c,
				       int32_t clear_after_read)
	{
		struct qb_ipcs_connection_stats_2 * stats;
	
		if (c == NULL) {
			errno = EINVAL;
			return NULL;
		}
		stats = calloc(1, sizeof(struct qb_ipcs_connection_stats_2));
		if (stats == NULL) {
			return NULL;
		}
	
		memcpy(stats, &c->stats, sizeof(struct qb_ipcs_connection_stats_2));
	
		if (c->service->funcs.q_len_get) {
			stats->event_q_length = c->service->funcs.q_len_get(&c->event);
		} else {
			stats->event_q_length = 0;
		}
		if (clear_after_read) {
			memset(&c->stats, 0, sizeof(struct qb_ipcs_connection_stats_2));
			c->stats.client_pid = c->pid;
		}
		return stats;
	}
	
	int32_t
	qb_ipcs_stats_get(struct qb_ipcs_service * s,
			  struct qb_ipcs_stats * stats, int32_t clear_after_read)
	{
		if (s == NULL) {
			return -EINVAL;
		}
		memcpy(stats, &s->stats, sizeof(struct qb_ipcs_stats));
		if (clear_after_read) {
			memset(&s->stats, 0, sizeof(struct qb_ipcs_stats));
		}
		return 0;
	}
	
	void
	qb_ipcs_connection_auth_set(qb_ipcs_connection_t *c, uid_t uid,
				    gid_t gid, mode_t mode)
	{
		if (c) {
			c->auth.uid = uid;
			c->auth.gid = gid;
			c->auth.mode = mode;
		}
	}
	
	int32_t
	qb_ipcs_connection_get_buffer_size(qb_ipcs_connection_t *c)
	{
		if (c == NULL) {
			return -EINVAL;
		}
	
		/* request, response, and event shoud all have the same
		 * buffer size allocated. It doesn't matter which we return
		 * here. */
		return c->response.max_msg_size;
	}
	
	void qb_ipcs_enforce_buffer_size(qb_ipcs_service_t *s, uint32_t buf_size)
	{
		if (s == NULL) {
			return;
		}
		s->max_buffer_size = buf_size;
	}