ctf: notif-iter.c: ensure that medops's get_stream() always returns the same

Knowing this, we can keep per-stream state in a CTF notif iter.

Signed-off-by: Philippe Proulx <eeppeliteloop@gmail.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

diff --git a/plugins/ctf/common/notif-iter/notif-iter.c b/plugins/ctf/common/notif-iter/notif-iter.c
index 06125b2315e3579bca9455c4b41b3c3ea0af9330..e02bfb8085ca9c3bf7884417b93e91e3e74c1e4f 100644 (file)
--- a/plugins/ctf/common/notif-iter/notif-iter.c
+++ b/plugins/ctf/common/notif-iter/notif-iter.c
@@ -162,6 +162,9 @@ struct bt_ctf_notif_iter {
        /* Current packet (NULL if not created yet) */
        struct bt_ctf_packet *packet;
 
+       /* Current stream (NULL if not set yet) */
+       struct bt_ctf_stream *stream;
+
        /*
         * Current timestamp_end field (to consider before switching packets).
         */
@@ -1654,6 +1657,7 @@ void bt_ctf_notif_iter_reset(struct bt_ctf_notif_iter *notit)
        BT_PUT(notit->meta.stream_class);
        BT_PUT(notit->meta.event_class);
        BT_PUT(notit->packet);
+       BT_PUT(notit->stream);
        put_all_dscopes(notit);
        notit->buf.addr = NULL;
        notit->buf.sz = 0;
@@ -2635,28 +2639,51 @@ end:
 }
 
 static
-void create_packet(struct bt_ctf_notif_iter *notit)
+int set_stream(struct bt_ctf_notif_iter *notit)
 {
-       int ret;
+       int ret = 0;
        struct bt_ctf_stream *stream = NULL;
-       struct bt_ctf_packet *packet = NULL;
 
-       BT_LOGV("Creating packet for packet notification: "
-               "notit-addr=%p", notit);
-
-       /* Ask the user for the stream */
        BT_LOGV("Calling user function (get stream): notit-addr=%p, "
                "stream-class-addr=%p, stream-class-name=\"%s\", "
                "stream-class-id=%" PRId64,
                notit, notit->meta.stream_class,
                bt_ctf_stream_class_get_name(notit->meta.stream_class),
                bt_ctf_stream_class_get_id(notit->meta.stream_class));
-       stream = notit->medium.medops.get_stream(notit->meta.stream_class,
-                       notit->medium.data);
-       BT_LOGV("User function returned: stream-addr=%p",
-               stream);
+       stream = bt_get(notit->medium.medops.get_stream(
+               notit->meta.stream_class, notit->medium.data));
+       BT_LOGV("User function returned: stream-addr=%p", stream);
        if (!stream) {
                BT_LOGW_STR("User function failed to return a stream object for the given stream class.");
+               ret = -1;
+               goto end;
+       }
+
+       if (notit->stream && stream != notit->stream) {
+               BT_LOGW("User function returned a different stream than the previous one for the same sequence of packets.");
+               ret = -1;
+               goto end;
+       }
+
+       BT_MOVE(notit->stream, stream);
+
+end:
+       bt_put(stream);
+       return ret;
+}
+
+static
+void create_packet(struct bt_ctf_notif_iter *notit)
+{
+       int ret;
+       struct bt_ctf_packet *packet = NULL;
+
+       BT_LOGV("Creating packet for packet notification: "
+               "notit-addr=%p", notit);
+
+       /* Ask the user for the stream */
+       ret = set_stream(notit);
+       if (ret) {
                goto error;
        }
 
@@ -2665,19 +2692,19 @@ void create_packet(struct bt_ctf_notif_iter *notit)
                "stream-class-addr=%p, "
                "stream-class-name=\"%s\", "
                "stream-class-id=%" PRId64,
-               notit, stream, notit->meta.stream_class,
+               notit, notit->stream, notit->meta.stream_class,
                bt_ctf_stream_class_get_name(notit->meta.stream_class),
                bt_ctf_stream_class_get_id(notit->meta.stream_class));
 
        /* Create packet */
-       packet = bt_ctf_packet_create(stream);
+       packet = bt_ctf_packet_create(notit->stream);
        if (!packet) {
                BT_LOGE("Cannot create packet from stream: "
                        "notit-addr=%p, stream-addr=%p, "
                        "stream-class-addr=%p, "
                        "stream-class-name=\"%s\", "
                        "stream-class-id=%" PRId64,
-                       notit, stream, notit->meta.stream_class,
+                       notit, notit->stream, notit->meta.stream_class,
                        bt_ctf_stream_class_get_name(notit->meta.stream_class),
                        bt_ctf_stream_class_get_id(notit->meta.stream_class));
                goto error;
@@ -2695,7 +2722,7 @@ void create_packet(struct bt_ctf_notif_iter *notit)
                                "stream-class-name=\"%s\", "
                                "stream-class-id=%" PRId64 ", "
                                "field-addr=%p",
-                               notit, packet, stream, notit->meta.stream_class,
+                               notit, packet, notit->stream, notit->meta.stream_class,
                                bt_ctf_stream_class_get_name(notit->meta.stream_class),
                                bt_ctf_stream_class_get_id(notit->meta.stream_class),
                                notit->dscopes.trace_packet_header);
@@ -2714,7 +2741,7 @@ void create_packet(struct bt_ctf_notif_iter *notit)
                                "stream-class-name=\"%s\", "
                                "stream-class-id=%" PRId64 ", "
                                "field-addr=%p",
-                               notit, packet, stream, notit->meta.stream_class,
+                               notit, packet, notit->stream, notit->meta.stream_class,
                                bt_ctf_stream_class_get_name(notit->meta.stream_class),
                                bt_ctf_stream_class_get_id(notit->meta.stream_class),
                                notit->dscopes.trace_packet_header);
@@ -2947,6 +2974,7 @@ void bt_ctf_notif_iter_destroy(struct bt_ctf_notif_iter *notit)
        BT_PUT(notit->meta.stream_class);
        BT_PUT(notit->meta.event_class);
        BT_PUT(notit->packet);
+       BT_PUT(notit->stream);
        BT_PUT(notit->cur_timestamp_end);
        put_all_dscopes(notit);