/*
- * Copyright (C) 2013 - Julien Desfossez <jdesfossez@efficios.com>
- * David Goulet <dgoulet@efficios.com>
- * 2015 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ * Copyright (C) 2013 Julien Desfossez <jdesfossez@efficios.com>
+ * Copyright (C) 2013 David Goulet <dgoulet@efficios.com>
+ * Copyright (C) 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.
+ * SPDX-License-Identifier: GPL-2.0-only
*
- * 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 _GNU_SOURCE
#define _LGPL_SOURCE
#include <common/common.h>
#include <urcu/rculist.h>
return vsession;
}
+int viewer_session_set_trace_chunk_copy(struct relay_viewer_session *vsession,
+ struct lttng_trace_chunk *relay_session_trace_chunk)
+{
+ int ret = 0;
+ struct lttng_trace_chunk *viewer_chunk;
+
+ assert(relay_session_trace_chunk);
+ lttng_trace_chunk_put(vsession->current_trace_chunk);
+ vsession->current_trace_chunk = NULL;
+
+ DBG("Copying relay session's current trace chunk to the viewer session");
+ viewer_chunk = lttng_trace_chunk_copy(relay_session_trace_chunk);
+ if (!viewer_chunk) {
+ ERR("Failed to create a viewer trace chunk from the relay session's current chunk");
+ ret = -1;
+ goto end;
+ }
+
+ vsession->current_trace_chunk = viewer_chunk;
+end:
+ return ret;
+}
+
/* The existence of session must be guaranteed by the caller. */
-int viewer_session_attach(struct relay_viewer_session *vsession,
+enum lttng_viewer_attach_return_code viewer_session_attach(
+ struct relay_viewer_session *vsession,
struct relay_session *session)
{
- int ret = 0;
+ enum lttng_viewer_attach_return_code viewer_attach_status =
+ LTTNG_VIEWER_ATTACH_OK;
+
+ ASSERT_LOCKED(session->lock);
/* Will not fail, as per the ownership guarantee. */
if (!session_get(session)) {
- ret = -1;
+ viewer_attach_status = LTTNG_VIEWER_ATTACH_UNK;
goto end;
}
- pthread_mutex_lock(&session->lock);
if (session->viewer_attached) {
- ret = -1;
+ viewer_attach_status = LTTNG_VIEWER_ATTACH_ALREADY;
} else {
+ int ret;
+
+ assert(session->current_trace_chunk);
+ assert(!vsession->current_trace_chunk);
session->viewer_attached = true;
+
+ ret = viewer_session_set_trace_chunk_copy(vsession,
+ session->current_trace_chunk);
+ if (ret) {
+ /*
+ * The live protocol does not define a generic error
+ * value for the "attach" command. The "unknown"
+ * status is used so that the viewer may handle this
+ * failure as if the session didn't exist anymore.
+ */
+ DBG("Failed to create a viewer trace chunk from the current trace chunk of session \"%s\", returning LTTNG_VIEWER_ATTACH_UNK",
+ session->session_name);
+ viewer_attach_status = LTTNG_VIEWER_ATTACH_UNK;
+ }
}
- if (!ret) {
+ if (viewer_attach_status == LTTNG_VIEWER_ATTACH_OK) {
pthread_mutex_lock(&vsession->session_list_lock);
/* Ownership is transfered to the list. */
cds_list_add_rcu(&session->viewer_session_node,
/* Put our local ref. */
session_put(session);
}
- /* Safe since we know the session exists. */
- pthread_mutex_unlock(&session->lock);
end:
- return ret;
+ return viewer_attach_status;
}
/* The existence of session must be guaranteed by the caller. */
void viewer_session_destroy(struct relay_viewer_session *vsession)
{
+ lttng_trace_chunk_put(vsession->current_trace_chunk);
free(vsession);
}
+/*
+ * Release ownership of all the streams of one session and detach the viewer.
+ */
+void viewer_session_close_one_session(struct relay_viewer_session *vsession,
+ struct relay_session *session)
+{
+ struct lttng_ht_iter iter;
+ struct relay_viewer_stream *vstream;
+
+ /*
+ * TODO: improvement: create more efficient list of
+ * vstream per session.
+ */
+ cds_lfht_for_each_entry(viewer_streams_ht->ht, &iter.iter,
+ vstream, stream_n.node) {
+ if (!viewer_stream_get(vstream)) {
+ continue;
+ }
+ if (vstream->stream->trace->session != session) {
+ viewer_stream_put(vstream);
+ continue;
+ }
+ /* Put local reference. */
+ viewer_stream_put(vstream);
+ /*
+ * We have reached one of the viewer stream's lifetime
+ * end condition. This "put" will cause the proper
+ * teardown of the viewer stream.
+ */
+ viewer_stream_put(vstream);
+ }
+ lttng_trace_chunk_put(vsession->current_trace_chunk);
+ vsession->current_trace_chunk = NULL;
+ viewer_session_detach(vsession, session);
+}
+
void viewer_session_close(struct relay_viewer_session *vsession)
{
struct relay_session *session;
rcu_read_lock();
cds_list_for_each_entry_rcu(session,
&vsession->session_list, viewer_session_node) {
- struct lttng_ht_iter iter;
- struct relay_viewer_stream *vstream;
-
- /*
- * TODO: improvement: create more efficient list of
- * vstream per session.
- */
- cds_lfht_for_each_entry(viewer_streams_ht->ht, &iter.iter,
- vstream, stream_n.node) {
- if (!viewer_stream_get(vstream)) {
- continue;
- }
- if (vstream->stream->trace->session != session) {
- viewer_stream_put(vstream);
- continue;
- }
- /* Put local reference. */
- viewer_stream_put(vstream);
- /*
- * We have reached one of the viewer stream's lifetime
- * end condition.
- */
- viewer_stream_put(vstream);
- }
-
- viewer_session_detach(vsession, session);
+ viewer_session_close_one_session(vsession, session);
}
rcu_read_unlock();
}
projects / lttng-tools.git / blobdiff