-/*
- * Copyright (C) 2013 - Julien Desfossez <jdesfossez@efficios.com>
- * David Goulet <dgoulet@efficios.com>
- * 2015 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License, version 2 only, as
- * published by the Free Software Foundation.
- *
- * This program 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 General Public License for
- * more details.
- *
- * You should have received a copy of the GNU General Public License along with
- * this program; if not, write to the Free Software Foundation, Inc., 51
- * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
- */
-
-#define _LGPL_SOURCE
-#include <common/common.h>
-#include <urcu/rculist.h>
-
-#include "lttng-relayd.h"
-#include "ctf-trace.h"
-#include "session.h"
-#include "stream.h"
-
-/* Global session id used in the session creation. */
-static uint64_t last_relay_session_id;
-static pthread_mutex_t last_relay_session_id_lock = PTHREAD_MUTEX_INITIALIZER;
-
-/*
- * Create a new session by assigning a new session ID.
- *
- * Return allocated session or else NULL.
- */
-struct relay_session *session_create(const char *session_name,
- const char *hostname, uint32_t live_timer,
- bool snapshot, uint32_t major, uint32_t minor)
-{
- struct relay_session *session;
-
- session = zmalloc(sizeof(*session));
- if (!session) {
- PERROR("relay session zmalloc");
- goto error;
- }
- if (lttng_strncpy(session->session_name, session_name,
- sizeof(session->session_name))) {
- goto error;
- }
- if (lttng_strncpy(session->hostname, hostname,
- sizeof(session->hostname))) {
- goto error;
- }
- session->ctf_traces_ht = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
- if (!session->ctf_traces_ht) {
- goto error;
- }
-
- pthread_mutex_lock(&last_relay_session_id_lock);
- session->id = ++last_relay_session_id;
- pthread_mutex_unlock(&last_relay_session_id_lock);
-
- session->major = major;
- session->minor = minor;
- lttng_ht_node_init_u64(&session->session_n, session->id);
- urcu_ref_init(&session->ref);
- CDS_INIT_LIST_HEAD(&session->recv_list);
- pthread_mutex_init(&session->lock, NULL);
- pthread_mutex_init(&session->recv_list_lock, NULL);
-
- session->live_timer = live_timer;
- session->snapshot = snapshot;
-
- lttng_ht_add_unique_u64(sessions_ht, &session->session_n);
- return session;
-
-error:
- free(session);
- return NULL;
-}
-
-/* Should be called with RCU read-side lock held. */
-bool session_get(struct relay_session *session)
-{
- return urcu_ref_get_unless_zero(&session->ref);
-}
-
-/*
- * Lookup a session within the session hash table using the session id
- * as key. A session reference is taken when a session is returned.
- * session_put() must be called on that session.
- *
- * Return session or NULL if not found.
- */
-struct relay_session *session_get_by_id(uint64_t id)
-{
- struct relay_session *session = NULL;
- struct lttng_ht_node_u64 *node;
- struct lttng_ht_iter iter;
-
- rcu_read_lock();
- lttng_ht_lookup(sessions_ht, &id, &iter);
- node = lttng_ht_iter_get_node_u64(&iter);
- if (!node) {
- DBG("Session find by ID %" PRIu64 " id NOT found", id);
- goto end;
- }
- session = caa_container_of(node, struct relay_session, session_n);
- DBG("Session find by ID %" PRIu64 " id found", id);
- if (!session_get(session)) {
- session = NULL;
- }
-end:
- rcu_read_unlock();
- return session;
-}
-
-static void rcu_destroy_session(struct rcu_head *rcu_head)
-{
- struct relay_session *session =
- caa_container_of(rcu_head, struct relay_session,
- rcu_node);
- /*
- * Since each trace has a reference on the session, it means
- * that if we are at the point where we teardown the session, no
- * trace belonging to that session exist at this point.
- * Calling lttng_ht_destroy in call_rcu worker thread so we
- * don't hold the RCU read-side lock while calling it.
- */
- lttng_ht_destroy(session->ctf_traces_ht);
- free(session);
-}
-
-/*
- * Delete session from the given hash table.
- *
- * Return lttng ht del error code being 0 on success and 1 on failure.
- */
-static int session_delete(struct relay_session *session)
-{
- struct lttng_ht_iter iter;
-
- iter.iter.node = &session->session_n.node;
- return lttng_ht_del(sessions_ht, &iter);
-}
-
-
-static void destroy_session(struct relay_session *session)
-{
- int ret;
-
- ret = session_delete(session);
- assert(!ret);
- call_rcu(&session->rcu_node, rcu_destroy_session);
-}
-
-void session_release(struct urcu_ref *ref)
-{
- struct relay_session *session =
- caa_container_of(ref, struct relay_session, ref);
-
- destroy_session(session);
-}
-
-void session_put(struct relay_session *session)
-{
- rcu_read_lock();
- urcu_ref_put(&session->ref, session_release);
- rcu_read_unlock();
-}
-
-int session_close(struct relay_session *session)
-{
- int ret = 0;
- struct ctf_trace *trace;
- struct lttng_ht_iter iter;
- struct relay_stream *stream;
-
- pthread_mutex_lock(&session->lock);
- DBG("closing session %" PRIu64 ": is conn already closed %d",
- session->id, session->connection_closed);
- session->connection_closed = true;
- pthread_mutex_unlock(&session->lock);
-
- rcu_read_lock();
- cds_lfht_for_each_entry(session->ctf_traces_ht->ht,
- &iter.iter, trace, node.node) {
- ret = ctf_trace_close(trace);
- if (ret) {
- goto rcu_unlock;
- }
- }
- cds_list_for_each_entry_rcu(stream, &session->recv_list,
- recv_node) {
- /* Close streams which have not been published yet. */
- try_stream_close(stream);
- }
-rcu_unlock:
- rcu_read_unlock();
- if (ret) {
- return ret;
- }
- /* Put self-reference from create. */
- session_put(session);
- return ret;
-}
-
-int session_abort(struct relay_session *session)
-{
- int ret = 0;
-
- if (!session) {
- return 0;
- }
-
- pthread_mutex_lock(&session->lock);
- DBG("aborting session %" PRIu64, session->id);
- session->aborted = true;
- pthread_mutex_unlock(&session->lock);
- return ret;
-}
-
-void print_sessions(void)
-{
- struct lttng_ht_iter iter;
- struct relay_session *session;
-
- if (!sessions_ht) {
- return;
- }
-
- rcu_read_lock();
- cds_lfht_for_each_entry(sessions_ht->ht, &iter.iter, session,
- session_n.node) {
- if (!session_get(session)) {
- continue;
- }
- DBG("session %p refcount %ld session %" PRIu64,
- session,
- session->ref.refcount,
- session->id);
- session_put(session);
- }
- rcu_read_unlock();
-}