Fix: Ensure stream endianness is set when initializing event class

This fixes a problem encountered by perf-to-ctf which would cause
an assert to hit whenever an event was instanciated before its
stream class was added to the trace.

This would cause the stream class to set its events' "native"
byte order with the "unknown endianness" value.

This modification ensures that an event's native endianness is
either set on addition to a stream class (when the stream is
already paired to a trace) or when the stream is added to a
trace.

Reported-by: Wang Nan <wangnan0@huawei.com>
Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

diff --git a/formats/ctf/ir/stream-class.c b/formats/ctf/ir/stream-class.c
index b1941415f9295981a2fb43e8ed0704cd7addbef3..6ad2cfa1583aaae18374b3276d866de8eaae660f 100644 (file)
--- a/formats/ctf/ir/stream-class.c
+++ b/formats/ctf/ir/stream-class.c
@@ -193,6 +193,15 @@ end:
        return ret;
 }
 
+BT_HIDDEN
+int _bt_ctf_stream_class_set_id(
+               struct bt_ctf_stream_class *stream_class, uint32_t id)
+{
+       stream_class->id = id;
+       stream_class->id_set = 1;
+       return 0;
+}
+
 int bt_ctf_stream_class_set_id(struct bt_ctf_stream_class *stream_class,
                uint32_t id)
 {
@@ -203,8 +212,10 @@ int bt_ctf_stream_class_set_id(struct bt_ctf_stream_class *stream_class,
                goto end;
        }
 
-       stream_class->id = id;
-       stream_class->id_set = 1;
+       ret = _bt_ctf_stream_class_set_id(stream_class, id);
+       if (ret) {
+               goto end;
+       }
 end:
        return ret;
 }
@@ -247,6 +258,18 @@ int bt_ctf_stream_class_add_event_class(
        bt_ctf_event_class_get(event_class);
        g_ptr_array_add(stream_class->event_classes, event_class);
        bt_ctf_event_class_freeze(event_class);
+
+       if (stream_class->byte_order) {
+               /*
+                * Only set native byte order if it has been initialized
+                * when the stream class was added to a trace.
+                *
+                * If not set here, this will be set when the stream
+                * classe will be added to a trace.
+                */
+               bt_ctf_event_class_set_native_byte_order(event_class,
+                       stream_class->byte_order);
+       }
 end:
        return ret;
 }
@@ -464,8 +487,6 @@ void bt_ctf_stream_class_put(struct bt_ctf_stream_class *stream_class)
 BT_HIDDEN
 void bt_ctf_stream_class_freeze(struct bt_ctf_stream_class *stream_class)
 {
-       size_t i;
-
        if (!stream_class) {
                return;
        }
@@ -475,33 +496,18 @@ void bt_ctf_stream_class_freeze(struct bt_ctf_stream_class *stream_class)
        bt_ctf_field_type_freeze(stream_class->packet_context_type);
        bt_ctf_field_type_freeze(stream_class->event_context_type);
        bt_ctf_clock_freeze(stream_class->clock);
-
-       bt_ctf_field_type_set_native_byte_order(
-               stream_class->event_header_type, stream_class->byte_order);
-       bt_ctf_field_type_set_native_byte_order(
-               stream_class->packet_context_type, stream_class->byte_order);
-       bt_ctf_field_type_set_native_byte_order(
-               stream_class->event_context_type, stream_class->byte_order);
-       for (i = 0; i < stream_class->event_classes->len; i++) {
-               bt_ctf_event_class_set_native_byte_order(
-                       g_ptr_array_index(stream_class->event_classes, i),
-                       stream_class->byte_order);
-               bt_ctf_event_class_freeze(
-                       g_ptr_array_index(stream_class->event_classes, i));
-       }
 }
 
 BT_HIDDEN
 int bt_ctf_stream_class_set_byte_order(struct bt_ctf_stream_class *stream_class,
        enum bt_ctf_byte_order byte_order)
 {
-       int ret = 0;
+       int i, ret = 0;
        int internal_byte_order;
 
        /* Note that "NATIVE" means the trace's endianness, not the host's. */
        if (!stream_class || byte_order <= BT_CTF_BYTE_ORDER_UNKNOWN ||
-               byte_order > BT_CTF_BYTE_ORDER_NETWORK ||
-               stream_class->frozen) {
+               byte_order > BT_CTF_BYTE_ORDER_NETWORK) {
                ret = -1;
                goto end;
        }
@@ -520,6 +526,23 @@ int bt_ctf_stream_class_set_byte_order(struct bt_ctf_stream_class *stream_class,
        }
 
        stream_class->byte_order = internal_byte_order;
+
+       /* Set native byte order to little or big endian */
+       bt_ctf_field_type_set_native_byte_order(
+               stream_class->event_header_type, stream_class->byte_order);
+       bt_ctf_field_type_set_native_byte_order(
+               stream_class->packet_context_type, stream_class->byte_order);
+       bt_ctf_field_type_set_native_byte_order(
+               stream_class->event_context_type, stream_class->byte_order);
+
+       /* Set all events' native byte order */
+       for (i = 0; i < stream_class->event_classes->len; i++) {
+               bt_ctf_event_class_set_native_byte_order(
+                       g_ptr_array_index(stream_class->event_classes, i),
+                       stream_class->byte_order);
+               bt_ctf_event_class_freeze(
+                       g_ptr_array_index(stream_class->event_classes, i));
+       }
 end:
        return ret;
 }

diff --git a/formats/ctf/ir/trace.c b/formats/ctf/ir/trace.c
index 5787f9f54f6f3be08d81078ab1d9066d1b190ec8..f782c5f50ff7cfb5b74c2ce38d8575262bdb1d72 100644 (file)
--- a/formats/ctf/ir/trace.c
+++ b/formats/ctf/ir/trace.c
@@ -159,7 +159,7 @@ struct bt_ctf_stream *bt_ctf_trace_create_stream(struct bt_ctf_trace *trace,
 
                if (stream_id < 0) {
                        /* Try to assign a new stream id */
-                       if (bt_ctf_stream_class_set_id(stream->stream_class,
+                       if (_bt_ctf_stream_class_set_id(stream->stream_class,
                                trace->next_stream_id++)) {
                                goto error;
                        }

diff --git a/include/babeltrace/ctf-ir/stream-class-internal.h b/include/babeltrace/ctf-ir/stream-class-internal.h
index 1a263268fd17726d36fb4ce770a42b4c36e2b818..8301fea019cdd7353c0421afe95102552c583eda 100644 (file)
--- a/include/babeltrace/ctf-ir/stream-class-internal.h
+++ b/include/babeltrace/ctf-ir/stream-class-internal.h
@@ -62,4 +62,9 @@ BT_HIDDEN
 int bt_ctf_stream_class_set_byte_order(struct bt_ctf_stream_class *stream_class,
                enum bt_ctf_byte_order byte_order);
 
+/* Set stream_class id without checking if the stream class is frozen */
+BT_HIDDEN
+int _bt_ctf_stream_class_set_id(struct bt_ctf_stream_class *stream_class,
+               uint32_t id);
+
 #endif /* BABELTRACE_CTF_IR_STREAM_CLASS_INTERNAL_H */