X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=formats%2Fctf%2Fir%2Fstream.c;h=4fe0589d00366a9e23be1a5a7c6e2ebb1e32fe4d;hb=af9296f358913f1fd3bc26e73237b582557cc104;hp=717925761336bfef2ada9b1f5b2287ff3f3fdd3e;hpb=a6b2126688597b7527281567973ee3ca7312c14b;p=babeltrace.git

diff --git a/formats/ctf/ir/stream.c b/formats/ctf/ir/stream.c
index 71792576..4fe0589d 100644
--- a/formats/ctf/ir/stream.c
+++ b/formats/ctf/ir/stream.c
@@ -26,15 +26,18 @@
  * SOFTWARE.
  */
 
-#include <babeltrace/ctf-ir/clock.h>
-#include <babeltrace/ctf-ir/clock-internal.h>
+#include <babeltrace/ctf-ir/clock-class.h>
+#include <babeltrace/ctf-writer/clock.h>
+#include <babeltrace/ctf-writer/clock-internal.h>
 #include <babeltrace/ctf-writer/event.h>
 #include <babeltrace/ctf-ir/event-internal.h>
-#include <babeltrace/ctf-ir/event-types-internal.h>
-#include <babeltrace/ctf-ir/event-fields-internal.h>
+#include <babeltrace/ctf-ir/field-types-internal.h>
+#include <babeltrace/ctf-ir/fields-internal.h>
 #include <babeltrace/ctf-ir/stream.h>
 #include <babeltrace/ctf-ir/stream-internal.h>
 #include <babeltrace/ctf-ir/stream-class-internal.h>
+#include <babeltrace/ctf-ir/trace-internal.h>
+#include <babeltrace/ctf-writer/writer-internal.h>
 #include <babeltrace/ref.h>
 #include <babeltrace/ctf-writer/functor-internal.h>
 #include <babeltrace/compiler.h>
@@ -44,8 +47,49 @@
 static
 void bt_ctf_stream_destroy(struct bt_object *obj);
 static
+int try_set_structure_field_integer(struct bt_ctf_field *, char *, uint64_t);
+static
 int set_structure_field_integer(struct bt_ctf_field *, char *, uint64_t);
 
+static
+int set_integer_field_value(struct bt_ctf_field* field, uint64_t value)
+{
+	int ret = 0;
+	struct bt_ctf_field_type *field_type = NULL;
+
+	if (!field) {
+		ret = -1;
+		goto end;
+	}
+
+	field_type = bt_ctf_field_get_type(field);
+	assert(field_type);
+
+	if (bt_ctf_field_type_get_type_id(field_type) !=
+			BT_CTF_TYPE_ID_INTEGER) {
+		/* Not an integer and the value is unset, error. */
+		ret = -1;
+		goto end;
+	}
+
+	if (bt_ctf_field_type_integer_get_signed(field_type)) {
+		ret = bt_ctf_field_signed_integer_set_value(field, (int64_t) value);
+		if (ret) {
+			/* Value is out of range, error. */
+			goto end;
+		}
+	} else {
+		ret = bt_ctf_field_unsigned_integer_set_value(field, value);
+		if (ret) {
+			/* Value is out of range, error. */
+			goto end;
+		}
+	}
+end:
+	bt_put(field_type);
+	return ret;
+}
+
 static
 int set_packet_header_magic(struct bt_ctf_stream *stream)
 {
@@ -59,7 +103,7 @@ int set_packet_header_magic(struct bt_ctf_stream *stream)
 		goto end;
 	}
 
-	if (!bt_ctf_field_validate(magic_field)) {
+	if (bt_ctf_field_is_set(magic_field)) {
 		/* Value already set. Not an error, skip. */
 		goto end;
 	}
@@ -68,7 +112,7 @@ int set_packet_header_magic(struct bt_ctf_stream *stream)
 	assert(magic_field_type);
 
 	if (bt_ctf_field_type_get_type_id(magic_field_type) !=
-		CTF_TYPE_INTEGER) {
+		BT_CTF_TYPE_ID_INTEGER) {
 		/* Magic field is not an integer. Not an error, skip. */
 		goto end;
 	}
@@ -111,7 +155,7 @@ int set_packet_header_uuid(struct bt_ctf_stream *stream)
 		goto end;
 	}
 
-	if (!bt_ctf_field_validate(uuid_field)) {
+	if (bt_ctf_field_is_set(uuid_field)) {
 		/* Value already set. Not an error, skip. */
 		goto end;
 	}
@@ -119,7 +163,7 @@ int set_packet_header_uuid(struct bt_ctf_stream *stream)
 	uuid_field_type = bt_ctf_field_get_type(uuid_field);
 	assert(uuid_field_type);
 	if (bt_ctf_field_type_get_type_id(uuid_field_type) !=
-		CTF_TYPE_ARRAY) {
+		BT_CTF_TYPE_ID_ARRAY) {
 		/* UUID field is not an array. Not an error, skip. */
 		goto end;
 	}
@@ -136,7 +180,7 @@ int set_packet_header_uuid(struct bt_ctf_stream *stream)
 		uuid_field_type);
 	assert(element_field_type);
 	if (bt_ctf_field_type_get_type_id(element_field_type) !=
-		CTF_TYPE_INTEGER) {
+		BT_CTF_TYPE_ID_INTEGER) {
 		/* UUID array elements are not integers. Not an error, skip */
 		goto end;
 	}
@@ -184,7 +228,7 @@ int set_packet_header_stream_id(struct bt_ctf_stream *stream)
 		goto end;
 	}
 
-	if (!bt_ctf_field_validate(stream_id_field)) {
+	if (bt_ctf_field_is_set(stream_id_field)) {
 		/* Value already set. Not an error, skip. */
 		goto end;
 	}
@@ -192,7 +236,7 @@ int set_packet_header_stream_id(struct bt_ctf_stream *stream)
 	stream_id_field_type = bt_ctf_field_get_type(stream_id_field);
 	assert(stream_id_field_type);
 	if (bt_ctf_field_type_get_type_id(stream_id_field_type) !=
-		CTF_TYPE_INTEGER) {
+		BT_CTF_TYPE_ID_INTEGER) {
 		/* stream_id field is not an integer. Not an error, skip. */
 		goto end;
 	}
@@ -252,21 +296,71 @@ void release_event(struct bt_ctf_event *event)
 	}
 }
 
-BT_HIDDEN
+static
+int create_stream_file(struct bt_ctf_writer *writer,
+		struct bt_ctf_stream *stream)
+{
+	int fd;
+	GString *filename = g_string_new(stream->stream_class->name->str);
+
+	if (stream->stream_class->name->len == 0) {
+		int64_t ret;
+
+		ret = bt_ctf_stream_class_get_id(stream->stream_class);
+		if (ret < 0) {
+			fd = -1;
+			goto error;
+		}
+
+		g_string_printf(filename, "stream_%" PRId64, ret);
+	}
+
+	g_string_append_printf(filename, "_%" PRIu32, stream->id);
+	fd = openat(writer->trace_dir_fd, filename->str,
+		O_RDWR | O_CREAT | O_TRUNC,
+		S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
+error:
+	g_string_free(filename, TRUE);
+	return fd;
+}
+
+static
+int set_stream_fd(struct bt_ctf_stream *stream, int fd)
+{
+	int ret = 0;
+
+	if (stream->pos.fd != -1) {
+		ret = -1;
+		goto end;
+	}
+
+	ctf_init_pos(&stream->pos, NULL, fd, O_RDWR);
+	stream->pos.fd = fd;
+end:
+	return ret;
+}
+
 struct bt_ctf_stream *bt_ctf_stream_create(
-	struct bt_ctf_stream_class *stream_class,
-	struct bt_ctf_trace *trace)
+		struct bt_ctf_stream_class *stream_class,
+		const char *name)
 {
 	int ret;
 	struct bt_ctf_stream *stream = NULL;
+	struct bt_ctf_trace *trace = NULL;
+	struct bt_ctf_writer *writer = NULL;
 
-	if (!stream_class || !trace) {
-		goto end;
+	if (!stream_class) {
+		goto error;
+	}
+
+	trace = bt_ctf_stream_class_get_trace(stream_class);
+	if (!trace) {
+		goto error;
 	}
 
 	stream = g_new0(struct bt_ctf_stream, 1);
 	if (!stream) {
-		goto end;
+		goto error;
 	}
 
 	bt_object_init(stream, bt_ctf_stream_destroy);
@@ -275,91 +369,100 @@ struct bt_ctf_stream *bt_ctf_stream_create(
 	 * reachable; it needs its parent to remain valid.
 	 */
 	bt_object_set_parent(stream, trace);
-	stream->packet_context = bt_ctf_field_create(
-		stream_class->packet_context_type);
-	if (!stream->packet_context) {
-		goto error;
-	}
+	stream->id = stream_class->next_stream_id++;
+	stream->stream_class = stream_class;
+	stream->pos.fd = -1;
 
-	/*
-	 * A stream class may not have a stream event context defined
-	 * in which case this stream will never have a stream_event_context
-	 * member since, after a stream's creation, the parent stream class
-	 * is "frozen" (immutable).
-	 */
-	if (stream_class->event_context_type) {
-		stream->event_context = bt_ctf_field_create(
-			stream_class->event_context_type);
-		if (!stream->event_context) {
+	if (name) {
+		stream->name = g_string_new(name);
+		if (!stream->name) {
 			goto error;
 		}
 	}
 
-	/* Initialize events_discarded */
-	ret = set_structure_field_integer(stream->packet_context,
-		"events_discarded", 0);
-	if (ret) {
-		goto error;
-	}
+	if (trace->is_created_by_writer) {
+		int fd;
+		writer = (struct bt_ctf_writer *)
+			bt_object_get_parent(trace);
 
-	stream->pos.fd = -1;
-	stream->id = stream_class->next_stream_id++;
-	stream->stream_class = stream_class;
-	stream->events = g_ptr_array_new_with_free_func(
-		(GDestroyNotify) release_event);
-	if (!stream->events) {
-		goto error;
-	}
-	if (stream_class->event_context_type) {
-		stream->event_contexts = g_ptr_array_new_with_free_func(
-			(GDestroyNotify) bt_put);
-		if (!stream->event_contexts) {
+		assert(writer);
+		if (stream_class->packet_context_type) {
+			stream->packet_context = bt_ctf_field_create(
+				stream_class->packet_context_type);
+			if (!stream->packet_context) {
+				goto error;
+			}
+
+			/* Initialize events_discarded */
+			ret = try_set_structure_field_integer(
+				stream->packet_context,
+				"events_discarded", 0);
+			if (ret != 1) {
+				goto error;
+			}
+		}
+
+		stream->events = g_ptr_array_new_with_free_func(
+			(GDestroyNotify) release_event);
+		if (!stream->events) {
 			goto error;
 		}
-	}
 
-	/* A trace is not allowed to have a NULL packet header */
-	assert(trace->packet_header_type);
-	stream->packet_header = bt_ctf_field_create(trace->packet_header_type);
-	if (!stream->packet_header) {
-		goto error;
-	}
-	/*
-	 * Attempt to populate the default trace packet header fields
-	 * (magic, uuid and stream_id). This will _not_ fail shall the
-	 * fields not be found or be of an incompatible type; they will
-	 * simply not be populated automatically. The user will have to
-	 * make sure to set the trace packet header fields himself before
-	 * flushing.
-	 */
-	ret = set_packet_header(stream);
-	if (ret) {
-		goto error;
+		/* A trace is not allowed to have a NULL packet header */
+		assert(trace->packet_header_type);
+		stream->packet_header =
+			bt_ctf_field_create(trace->packet_header_type);
+		if (!stream->packet_header) {
+			goto error;
+		}
+
+		/*
+		 * Attempt to populate the default trace packet header fields
+		 * (magic, uuid and stream_id). This will _not_ fail shall the
+		 * fields not be found or be of an incompatible type; they will
+		 * simply not be populated automatically. The user will have to
+		 * make sure to set the trace packet header fields himself
+		 * before flushing.
+		 */
+		ret = set_packet_header(stream);
+		if (ret) {
+			goto error;
+		}
+
+		/* Create file associated with this stream */
+		fd = create_stream_file(writer, stream);
+		if (fd < 0) {
+			goto error;
+		}
+
+		ret = set_stream_fd(stream, fd);
+		if (ret) {
+			goto error;
+		}
+
+		/* Freeze the writer */
+		bt_ctf_writer_freeze(writer);
+	} else {
+		/* Non-writer stream indicated by a negative FD */
+		ret = set_stream_fd(stream, -1);
+		if (ret) {
+			goto error;
+		}
 	}
-end:
+
+	/* Add this stream to the trace's streams */
+	g_ptr_array_add(trace->streams, stream);
+
+	BT_PUT(trace);
+	BT_PUT(writer);
 	return stream;
 error:
 	BT_PUT(stream);
-	bt_put(trace);
+	BT_PUT(trace);
+	BT_PUT(writer);
 	return stream;
 }
 
-BT_HIDDEN
-int bt_ctf_stream_set_fd(struct bt_ctf_stream *stream, int fd)
-{
-	int ret = 0;
-
-	if (stream->pos.fd != -1) {
-		ret = -1;
-		goto end;
-	}
-
-	ctf_init_pos(&stream->pos, NULL, fd, O_RDWR);
-	stream->pos.fd = fd;
-end:
-	return ret;
-}
-
 struct bt_ctf_stream_class *bt_ctf_stream_get_class(
 		struct bt_ctf_stream *stream)
 {
@@ -383,7 +486,8 @@ int bt_ctf_stream_get_discarded_events_count(
 	struct bt_ctf_field *events_discarded_field = NULL;
 	struct bt_ctf_field_type *events_discarded_field_type = NULL;
 
-	if (!stream || !count || !stream->packet_context) {
+	if (!stream || !count || !stream->packet_context ||
+			stream->pos.fd < 0) {
 		ret = -1;
 		goto end;
 	}
@@ -446,7 +550,7 @@ void bt_ctf_stream_append_discarded_events(struct bt_ctf_stream *stream,
 	struct bt_ctf_field *events_discarded_field = NULL;
 	struct bt_ctf_field_type *events_discarded_field_type = NULL;
 
-	if (!stream || !stream->packet_context) {
+	if (!stream || !stream->packet_context || stream->pos.fd < 0) {
 		goto end;
 	}
 
@@ -494,49 +598,125 @@ end:
 	bt_put(events_discarded_field_type);
 }
 
-int bt_ctf_stream_append_event(struct bt_ctf_stream *stream,
+static int auto_populate_event_header(struct bt_ctf_stream *stream,
 		struct bt_ctf_event *event)
 {
 	int ret = 0;
-	struct bt_ctf_field *event_context_copy = NULL;
+	struct bt_ctf_field *id_field = NULL, *timestamp_field = NULL;
+	struct bt_ctf_clock_class *mapped_clock_class = NULL;
 
-	if (!stream || !event) {
+	if (!event || event->frozen) {
 		ret = -1;
 		goto end;
 	}
 
-	bt_object_set_parent(event, stream);
-	ret = bt_ctf_event_populate_event_header(event);
-	if (ret) {
+	/*
+	 * The condition to automatically set the ID are:
+	 *
+	 * 1. The event header field "id" exists and is an integer
+	 *    field.
+	 * 2. The event header field "id" is NOT set.
+	 */
+	id_field = bt_ctf_field_structure_get_field(event->event_header, "id");
+	if (id_field && !bt_ctf_field_is_set(id_field)) {
+		ret = set_integer_field_value(id_field,
+			(uint64_t) bt_ctf_event_class_get_id(
+					event->event_class));
+		if (ret) {
+			goto end;
+		}
+	}
+
+	/*
+	 * The conditions to automatically set the timestamp are:
+	 *
+	 * 1. The event header field "timestamp" exists and is an
+	 *    integer field.
+	 * 2. This stream's class has a registered clock (set with
+	 *    bt_ctf_stream_class_set_clock()).
+	 * 3. The event header field "timestamp" has its type mapped to
+	 *    a clock class which is also the clock class of this
+	 *    stream's class's registered clock.
+	 * 4. The event header field "timestamp" is NOT set.
+	 */
+	timestamp_field = bt_ctf_field_structure_get_field(event->event_header,
+			"timestamp");
+	if (timestamp_field && !bt_ctf_field_is_set(timestamp_field) &&
+			stream->stream_class->clock) {
+		struct bt_ctf_clock_class *stream_class_clock_class =
+			stream->stream_class->clock->clock_class;
+		struct bt_ctf_field_type *timestamp_field_type =
+			bt_ctf_field_get_type(timestamp_field);
+
+		assert(timestamp_field_type);
+		mapped_clock_class =
+			bt_ctf_field_type_integer_get_mapped_clock_class(
+				timestamp_field_type);
+		BT_PUT(timestamp_field_type);
+		if (mapped_clock_class == stream_class_clock_class) {
+			uint64_t timestamp;
+
+			ret = bt_ctf_clock_get_value(
+				stream->stream_class->clock,
+				&timestamp);
+			if (ret) {
+				goto end;
+			}
+
+			ret = set_integer_field_value(timestamp_field,
+					timestamp);
+			if (ret) {
+				goto end;
+			}
+		}
+	}
+
+end:
+	bt_put(id_field);
+	bt_put(timestamp_field);
+	bt_put(mapped_clock_class);
+	return ret;
+}
+
+int bt_ctf_stream_append_event(struct bt_ctf_stream *stream,
+		struct bt_ctf_event *event)
+{
+	int ret = 0;
+
+	if (!stream || !event || stream->pos.fd < 0) {
+		ret = -1;
 		goto end;
 	}
 
-	/* Make sure the event's payload is set */
-	ret = bt_ctf_event_validate(event);
-	if (ret) {
+	/*
+	 * The event is not supposed to have a parent stream at this
+	 * point. The only other way an event can have a parent stream
+	 * is if it was assigned when setting a packet to the event,
+	 * in which case the packet's stream is not a writer stream,
+	 * and thus the user is trying to append an event which belongs
+	 * to another stream.
+	 */
+	if (event->base.parent) {
+		ret = -1;
 		goto end;
 	}
 
-	/* Sample the current stream event context by copying it */
-	if (stream->event_context) {
-		/* Make sure the event context's payload is set */
-		ret = bt_ctf_field_validate(stream->event_context);
-		if (ret) {
-			goto end;
-		}
+	bt_object_set_parent(event, stream);
+	ret = auto_populate_event_header(stream, event);
+	if (ret) {
+		goto error;
+	}
 
-		event_context_copy = bt_ctf_field_copy(stream->event_context);
-		if (!event_context_copy) {
-			ret = -1;
-			goto end;
-		}
+	/* Make sure the various scopes of the event are set */
+	ret = bt_ctf_event_validate(event);
+	if (ret) {
+		goto error;
 	}
 
-	/* Save the new event along with its associated stream event context */
+	/* Save the new event and freeze it */
+	bt_ctf_event_freeze(event);
 	g_ptr_array_add(stream->events, event);
-	if (event_context_copy) {
-		g_ptr_array_add(stream->event_contexts, event_context_copy);
-	}
+
 	/*
 	 * Event had to hold a reference to its event class as long as it wasn't
 	 * part of the same trace hierarchy. From now on, the event and its
@@ -544,14 +724,17 @@ int bt_ctf_stream_append_event(struct bt_ctf_stream *stream,
 	 * longer needed.
 	 */
 	bt_put(event->event_class);
+
 end:
-	if (ret) {
-		/*
-		 * Orphan the event; we were not succesful in associating it to
-		 * a stream.
-		 */
-		bt_object_set_parent(event, NULL);
-	}
+	return ret;
+
+error:
+	/*
+	 * Orphan the event; we were not successful in associating it to
+	 * a stream.
+	 */
+	bt_object_set_parent(event, NULL);
+
 	return ret;
 }
 
@@ -560,7 +743,7 @@ struct bt_ctf_field *bt_ctf_stream_get_packet_context(
 {
 	struct bt_ctf_field *packet_context = NULL;
 
-	if (!stream) {
+	if (!stream || stream->pos.fd < 0) {
 		goto end;
 	}
 
@@ -578,73 +761,31 @@ int bt_ctf_stream_set_packet_context(struct bt_ctf_stream *stream,
 	int ret = 0;
 	struct bt_ctf_field_type *field_type;
 
-	if (!stream || !field) {
+	if (!stream || stream->pos.fd < 0) {
 		ret = -1;
 		goto end;
 	}
 
 	field_type = bt_ctf_field_get_type(field);
-	if (field_type != stream->stream_class->packet_context_type) {
+	if (bt_ctf_field_type_compare(field_type,
+			stream->stream_class->packet_context_type)) {
 		ret = -1;
 		goto end;
 	}
 
 	bt_put(field_type);
-	bt_get(field);
 	bt_put(stream->packet_context);
-	stream->packet_context = field;
+	stream->packet_context = bt_get(field);
 end:
 	return ret;
 }
 
-struct bt_ctf_field *bt_ctf_stream_get_event_context(
-		struct bt_ctf_stream *stream)
-{
-	struct bt_ctf_field *event_context = NULL;
-
-	if (!stream) {
-		goto end;
-	}
-
-	event_context = stream->event_context;
-	if (event_context) {
-		bt_get(event_context);
-	}
-end:
-	return event_context;
-}
-
-int bt_ctf_stream_set_event_context(struct bt_ctf_stream *stream,
-		struct bt_ctf_field *field)
-{
-	int ret = 0;
-	struct bt_ctf_field_type *field_type = NULL;
-
-	if (!stream || !field) {
-		ret = -1;
-		goto end;
-	}
-
-	field_type = bt_ctf_field_get_type(field);
-	if (field_type != stream->stream_class->event_context_type) {
-		ret = -1;
-		goto end;
-	}
-
-	bt_get(field);
-	bt_put(stream->event_context);
-	stream->event_context = field;
-end:
-	bt_put(field_type);
-	return ret;
-}
-
 struct bt_ctf_field *bt_ctf_stream_get_packet_header(
 		struct bt_ctf_stream *stream)
 {
 	struct bt_ctf_field *packet_header = NULL;
 
-	if (!stream) {
+	if (!stream || stream->pos.fd < 0) {
 		goto end;
 	}
 
@@ -663,21 +804,20 @@ int bt_ctf_stream_set_packet_header(struct bt_ctf_stream *stream,
 	struct bt_ctf_trace *trace = NULL;
 	struct bt_ctf_field_type *field_type = NULL;
 
-	if (!stream || !field) {
+	if (!stream || stream->pos.fd < 0) {
 		ret = -1;
 		goto end;
 	}
 
 	trace = (struct bt_ctf_trace *) bt_object_get_parent(stream);
 	field_type = bt_ctf_field_get_type(field);
-	if (field_type != trace->packet_header_type) {
+	if (bt_ctf_field_type_compare(field_type, trace->packet_header_type)) {
 		ret = -1;
 		goto end;
 	}
 
-	bt_get(field);
 	bt_put(stream->packet_header);
-	stream->packet_header = field;
+	stream->packet_header = bt_get(field);
 end:
 	BT_PUT(trace);
 	bt_put(field_type);
@@ -701,7 +841,7 @@ int get_event_header_timestamp(struct bt_ctf_field *event_header, uint64_t *time
 	timestamp_field_type = bt_ctf_field_get_type(timestamp_field);
 	assert(timestamp_field_type);
 	if (bt_ctf_field_type_get_type_id(timestamp_field_type) !=
-		CTF_TYPE_INTEGER) {
+		BT_CTF_TYPE_ID_INTEGER) {
 		ret = -1;
 		goto end;
 	}
@@ -735,6 +875,8 @@ int bt_ctf_stream_flush(struct bt_ctf_stream *stream)
 	uint64_t timestamp_begin, timestamp_end, events_discarded;
 	struct bt_ctf_field *integer = NULL;
 	struct ctf_stream_pos packet_context_pos;
+	bool empty_packet;
+	uint64_t packet_size_bits;
 
 	if (!stream || stream->pos.fd < 0) {
 		/*
@@ -745,14 +887,17 @@ int bt_ctf_stream_flush(struct bt_ctf_stream *stream)
 		goto end;
 	}
 
-	if (!stream->events->len) {
+	if (!stream->packet_context && stream->flushed_packet_count > 0) {
+		/*
+		 * A stream without a packet context, and thus without
+		 * content and packet size members, can't have more than
+		 * one packet.
+		 */
+		ret = -1;
 		goto end;
 	}
 
-	ret = bt_ctf_field_validate(stream->packet_header);
-	if (ret) {
-		goto end;
-	}
+	empty_packet = (stream->events->len == 0);
 
 	/* mmap the next packet */
 	ctf_packet_seek(&stream->pos.parent, 0, SEEK_CUR);
@@ -762,66 +907,51 @@ int bt_ctf_stream_flush(struct bt_ctf_stream *stream)
 		goto end;
 	}
 
-	/* Set the default context attributes if present and unset. */
-	if (!get_event_header_timestamp(
-		((struct bt_ctf_event *) g_ptr_array_index(
-		stream->events, 0))->event_header, &timestamp_begin)) {
-		ret = set_structure_field_integer(stream->packet_context,
-			"timestamp_begin", timestamp_begin);
-		if (ret) {
-			goto end;
+	if (stream->packet_context) {
+		/* Set the default context attributes if present and unset. */
+		if (!empty_packet && !get_event_header_timestamp(
+			((struct bt_ctf_event *) g_ptr_array_index(
+				stream->events, 0))->event_header, &timestamp_begin)) {
+			ret = try_set_structure_field_integer(
+				stream->packet_context,
+				"timestamp_begin", timestamp_begin);
+			if (ret < 0) {
+				goto end;
+			}
 		}
-	}
 
-	if (!get_event_header_timestamp(
-		((struct bt_ctf_event *) g_ptr_array_index(
-		stream->events, stream->events->len - 1))->event_header,
-		&timestamp_end)) {
+		if (!empty_packet && !get_event_header_timestamp(
+			((struct bt_ctf_event *) g_ptr_array_index(
+				stream->events, stream->events->len - 1))->event_header,
+				&timestamp_end)) {
 
-		ret = set_structure_field_integer(stream->packet_context,
-			"timestamp_end", timestamp_end);
-		if (ret) {
+			ret = try_set_structure_field_integer(
+				stream->packet_context,
+				"timestamp_end", timestamp_end);
+			if (ret < 0) {
+				goto end;
+			}
+		}
+		ret = try_set_structure_field_integer(stream->packet_context,
+			"content_size", UINT64_MAX);
+		if (ret < 0) {
 			goto end;
 		}
-	}
-	ret = set_structure_field_integer(stream->packet_context,
-		"content_size", UINT64_MAX);
-	if (ret) {
-		goto end;
-	}
-
-	ret = set_structure_field_integer(stream->packet_context,
-		"packet_size", UINT64_MAX);
-	if (ret) {
-		goto end;
-	}
-
-	/* Write packet context */
-	memcpy(&packet_context_pos, &stream->pos,
-	       sizeof(struct ctf_stream_pos));
-	ret = bt_ctf_field_serialize(stream->packet_context,
-		&stream->pos);
-	if (ret) {
-		goto end;
-	}
-
-	ret = bt_ctf_stream_get_discarded_events_count(stream,
-		&events_discarded);
-	if (ret) {
-		goto end;
-	}
 
-	/* Unset the packet context's fields. */
-	ret = bt_ctf_field_reset(stream->packet_context);
-	if (ret) {
-		goto end;
-	}
+		ret = try_set_structure_field_integer(stream->packet_context,
+			"packet_size", UINT64_MAX);
+		if (ret < 0) {
+			goto end;
+		}
 
-	/* Set the previous number of discarded events. */
-	ret = set_structure_field_integer(stream->packet_context,
-		"events_discarded", events_discarded);
-	if (ret) {
-		goto end;
+		/* Write packet context */
+		memcpy(&packet_context_pos, &stream->pos,
+			sizeof(struct ctf_stream_pos));
+		ret = bt_ctf_field_serialize(stream->packet_context,
+			&stream->pos);
+		if (ret) {
+			goto end;
+		}
 	}
 
 	for (i = 0; i < stream->events->len; i++) {
@@ -841,10 +971,9 @@ int bt_ctf_stream_flush(struct bt_ctf_stream *stream)
 		}
 
 		/* Write stream event context */
-		if (stream->event_contexts) {
+		if (event->stream_event_context) {
 			ret = bt_ctf_field_serialize(
-				g_ptr_array_index(stream->event_contexts, i),
-				&stream->pos);
+				event->stream_event_context, &stream->pos);
 			if (ret) {
 				goto end;
 			}
@@ -857,36 +986,41 @@ int bt_ctf_stream_flush(struct bt_ctf_stream *stream)
 		}
 	}
 
-	/*
-	 * Update the packet total size and content size and overwrite the
-	 * packet context.
-	 * Copy base_mma as the packet may have been remapped (e.g. when a
-	 * packet is resized).
-	 */
-	packet_context_pos.base_mma = stream->pos.base_mma;
-	ret = set_structure_field_integer(stream->packet_context,
-		"content_size", stream->pos.offset);
-	if (ret) {
-		goto end;
-	}
+	/* Rounded-up in case content_size is not byte-aligned. */
+	packet_size_bits = (stream->pos.offset + (CHAR_BIT - 1)) &
+		~(CHAR_BIT - 1);
+	stream->pos.packet_size = packet_size_bits;
 
-	ret = set_structure_field_integer(stream->packet_context,
-		"packet_size", stream->pos.packet_size);
-	if (ret) {
-		goto end;
-	}
+	if (stream->packet_context) {
+		/*
+		 * Update the packet total size and content size and overwrite
+		 * the packet context.
+		 * Copy base_mma as the packet may have been remapped (e.g. when
+		 * a packet is resized).
+		 */
+		packet_context_pos.base_mma = stream->pos.base_mma;
+		ret = set_structure_field_integer(stream->packet_context,
+			"content_size", stream->pos.offset);
+		if (ret) {
+			goto end;
+		}
 
-	ret = bt_ctf_field_serialize(stream->packet_context,
-		&packet_context_pos);
-	if (ret) {
-		goto end;
+		ret = set_structure_field_integer(stream->packet_context,
+			"packet_size", packet_size_bits);
+		if (ret) {
+			goto end;
+		}
+
+		ret = bt_ctf_field_serialize(stream->packet_context,
+			&packet_context_pos);
+		if (ret) {
+			goto end;
+		}
 	}
 
 	g_ptr_array_set_size(stream->events, 0);
-	if (stream->event_contexts) {
-		g_ptr_array_set_size(stream->event_contexts, 0);
-	}
 	stream->flushed_packet_count++;
+	stream->size += packet_size_bits / CHAR_BIT;
 end:
 	bt_put(integer);
 	return ret;
@@ -909,25 +1043,42 @@ void bt_ctf_stream_destroy(struct bt_object *obj)
 
 	stream = container_of(obj, struct bt_ctf_stream, base);
 	ctf_fini_pos(&stream->pos);
-	if (stream->pos.fd >= 0 && close(stream->pos.fd)) {
-		perror("close");
+	if (stream->pos.fd >= 0) {
+		int ret;
+
+		/*
+		 * Truncate the file's size to the minimum required to fit the
+		 * last packet as we might have grown it too much on the last
+		 * mmap.
+		 */
+		do {
+			ret = ftruncate(stream->pos.fd, stream->size);
+		} while (ret == -1 && errno == EINTR);
+		if (ret) {
+			perror("ftruncate");
+		}
+
+		if (close(stream->pos.fd)) {
+			perror("close");
+		}
 	}
 
 	if (stream->events) {
 		g_ptr_array_free(stream->events, TRUE);
 	}
-	if (stream->event_contexts) {
-		g_ptr_array_free(stream->event_contexts, TRUE);
+
+	if (stream->name) {
+		g_string_free(stream->name, TRUE);
 	}
+
 	bt_put(stream->packet_header);
 	bt_put(stream->packet_context);
-	bt_put(stream->event_context);
 	g_free(stream);
 }
 
 static
-int set_structure_field_integer(struct bt_ctf_field *structure, char *name,
-		uint64_t value)
+int _set_structure_field_integer(struct bt_ctf_field *structure, char *name,
+		uint64_t value, bool force)
 {
 	int ret = 0;
 	struct bt_ctf_field_type *field_type = NULL;
@@ -945,15 +1096,14 @@ int set_structure_field_integer(struct bt_ctf_field *structure, char *name,
 	}
 
 	/* Make sure the payload has not already been set. */
-	if (!bt_ctf_field_validate(integer)) {
+	if (!force && bt_ctf_field_is_set(integer)) {
 		/* Payload already set, not an error */
 		goto end;
 	}
 
 	field_type = bt_ctf_field_get_type(integer);
-	/* Something is serioulsly wrong */
 	assert(field_type);
-	if (bt_ctf_field_type_get_type_id(field_type) != CTF_TYPE_INTEGER) {
+	if (bt_ctf_field_type_get_type_id(field_type) != BT_CTF_TYPE_ID_INTEGER) {
 		/*
 		 * The user most likely meant for us to populate this field
 		 * automatically. However, we can only do this if the field
@@ -969,8 +1119,57 @@ int set_structure_field_integer(struct bt_ctf_field *structure, char *name,
 	} else {
 		ret = bt_ctf_field_unsigned_integer_set_value(integer, value);
 	}
+	ret = !ret ? 1 : ret;
 end:
 	bt_put(integer);
 	bt_put(field_type);
 	return ret;
 }
+
+static
+int set_structure_field_integer(struct bt_ctf_field *structure, char *name,
+		uint64_t value)
+{
+	return _set_structure_field_integer(structure, name, value, true);
+}
+
+/*
+ * Returns the following codes:
+ * 1 if the field was found and set,
+ * 0 if nothing was done (field not found, or was already set),
+ * <0 if an error was encoutered
+ */
+static
+int try_set_structure_field_integer(struct bt_ctf_field *structure, char *name,
+		uint64_t value)
+{
+	return _set_structure_field_integer(structure, name, value, false);
+}
+
+const char *bt_ctf_stream_get_name(struct bt_ctf_stream *stream)
+{
+	const char *name = NULL;
+
+	if (!stream) {
+		goto end;
+	}
+
+	name = stream->name ? stream->name->str : NULL;
+
+end:
+	return name;
+}
+
+int bt_ctf_stream_is_writer(struct bt_ctf_stream *stream)
+{
+	int ret = -1;
+
+	if (!stream) {
+		goto end;
+	}
+
+	ret = (stream->pos.fd >= 0);
+
+end:
+	return ret;
+}