+void bt_iter_free_pos(struct bt_iter_pos *iter_pos)
+{
+ if (!iter_pos)
+ return;
+
+ if (iter_pos->type == BT_SEEK_RESTORE && iter_pos->u.restore) {
+ if (iter_pos->u.restore->stream_saved_pos) {
+ g_array_free(
+ iter_pos->u.restore->stream_saved_pos,
+ TRUE);
+ }
+ g_free(iter_pos->u.restore);
+ }
+ g_free(iter_pos);
+}
+
+/*
+ * seek_file_stream_by_timestamp
+ *
+ * Browse a filestream by index, if an index contains the timestamp passed in
+ * argument, seek inside the corresponding packet it until we find the event we
+ * are looking for (either the exact timestamp or the event just after the
+ * timestamp).
+ *
+ * Return 0 if the seek succeded, EOF if we didn't find any packet
+ * containing the timestamp, or a positive integer for error.
+ *
+ * TODO: this should be turned into a binary search! It is currently
+ * doing a linear search in the packets. This is a O(n) operation on a
+ * very frequent code path.
+ */
+static int seek_file_stream_by_timestamp(struct ctf_file_stream *cfs,
+ uint64_t timestamp)
+{
+ struct ctf_stream_pos *stream_pos;
+ struct packet_index *index;
+ int i, ret;
+
+ stream_pos = &cfs->pos;
+ for (i = 0; i < stream_pos->packet_real_index->len; i++) {
+ index = &g_array_index(stream_pos->packet_real_index,
+ struct packet_index, i);
+ if (index->timestamp_end < timestamp)
+ continue;
+
+ stream_pos->packet_seek(&stream_pos->parent, i, SEEK_SET);
+ do {
+ ret = stream_read_event(cfs);
+ } while (cfs->parent.real_timestamp < timestamp && ret == 0);
+
+ /* Can return either EOF, 0, or error (> 0). */
+ return ret;
+ }
+ /*
+ * Cannot find the timestamp within the stream packets, return
+ * EOF.
+ */
+ return EOF;
+}
+
+/*
+ * seek_ctf_trace_by_timestamp : for each file stream, seek to the event with
+ * the corresponding timestamp
+ *
+ * Return 0 on success.
+ * If the timestamp is not part of any file stream, return EOF to inform the
+ * user the timestamp is out of the scope.
+ * On other errors, return positive value.
+ */
+static int seek_ctf_trace_by_timestamp(struct ctf_trace *tin,
+ uint64_t timestamp, struct ptr_heap *stream_heap)
+{
+ int i, j, ret;
+ int found = 0;
+
+ /* for each stream_class */
+ for (i = 0; i < tin->streams->len; i++) {
+ struct ctf_stream_declaration *stream_class;
+
+ stream_class = g_ptr_array_index(tin->streams, i);
+ if (!stream_class)
+ continue;
+ /* for each file_stream */
+ for (j = 0; j < stream_class->streams->len; j++) {
+ struct ctf_stream_definition *stream;
+ struct ctf_file_stream *cfs;
+
+ stream = g_ptr_array_index(stream_class->streams, j);
+ if (!stream)
+ continue;
+ cfs = container_of(stream, struct ctf_file_stream,
+ parent);
+ ret = seek_file_stream_by_timestamp(cfs, timestamp);
+ if (ret == 0) {
+ /* Add to heap */
+ ret = heap_insert(stream_heap, cfs);
+ if (ret) {
+ /* Return positive error. */
+ return -ret;
+ }
+ found = 1;
+ } else if (ret > 0) {
+ /*
+ * Error in seek (not EOF), failure.
+ */
+ return ret;
+ }
+ /* on EOF just do not put stream into heap. */
+ }
+ }
+
+ return found ? 0 : EOF;
+}
+
+/*
+ * Find timestamp of last event in the stream.
+ *
+ * Return value: 0 if OK, positive error value on error, EOF if no
+ * events were found.
+ */
+static int find_max_timestamp_ctf_file_stream(struct ctf_file_stream *cfs,
+ uint64_t *timestamp_end)
+{
+ int ret, count = 0, i;
+ uint64_t timestamp = 0;
+ struct ctf_stream_pos *stream_pos;
+
+ stream_pos = &cfs->pos;
+ /*
+ * We start by the last packet, and iterate backwards until we
+ * either find at least one event, or we reach the first packet
+ * (some packets can be empty).
+ */
+ for (i = stream_pos->packet_real_index->len - 1; i >= 0; i--) {
+ stream_pos->packet_seek(&stream_pos->parent, i, SEEK_SET);
+ count = 0;
+ /* read each event until we reach the end of the stream */
+ do {
+ ret = stream_read_event(cfs);
+ if (ret == 0) {
+ count++;
+ timestamp = cfs->parent.real_timestamp;
+ }
+ } while (ret == 0);
+
+ /* Error */
+ if (ret > 0)
+ goto end;
+ assert(ret == EOF);
+ if (count)
+ break;
+ }
+
+ if (count) {
+ *timestamp_end = timestamp;
+ ret = 0;
+ } else {
+ /* Return EOF if no events were found */
+ ret = EOF;
+ }
+end:
+ return ret;
+}
+
+/*
+ * Find the stream within a stream class that contains the event with
+ * the largest timestamp, and save that timestamp.
+ *
+ * Return 0 if OK, EOF if no events were found in the streams, or
+ * positive value on error.
+ */
+static int find_max_timestamp_ctf_stream_class(
+ struct ctf_stream_declaration *stream_class,
+ struct ctf_file_stream **cfsp,
+ uint64_t *max_timestamp)
+{
+ int ret = EOF, i, found = 0;
+
+ for (i = 0; i < stream_class->streams->len; i++) {
+ struct ctf_stream_definition *stream;
+ struct ctf_file_stream *cfs;
+ uint64_t current_max_ts = 0;
+
+ stream = g_ptr_array_index(stream_class->streams, i);
+ if (!stream)
+ continue;
+ cfs = container_of(stream, struct ctf_file_stream, parent);
+ ret = find_max_timestamp_ctf_file_stream(cfs, ¤t_max_ts);
+ if (ret == EOF)
+ continue;
+ if (ret != 0)
+ break;
+ if (current_max_ts >= *max_timestamp) {
+ *max_timestamp = current_max_ts;
+ *cfsp = cfs;
+ found = 1;
+ }
+ }
+ assert(ret >= 0 || ret == EOF);
+ if (found) {
+ return 0;
+ }
+ return ret;
+}
+
+/*
+ * seek_last_ctf_trace_collection: seek trace collection to last event.
+ *
+ * Return 0 if OK, EOF if no events were found, or positive error value
+ * on error.
+ */
+static int seek_last_ctf_trace_collection(struct trace_collection *tc,
+ struct ctf_file_stream **cfsp)
+{
+ int i, j, ret;
+ int found = 0;
+ uint64_t max_timestamp = 0;
+
+ if (!tc)
+ return 1;
+
+ /* For each trace in the trace_collection */
+ for (i = 0; i < tc->array->len; i++) {
+ struct ctf_trace *tin;
+ struct trace_descriptor *td_read;
+
+ td_read = g_ptr_array_index(tc->array, i);
+ if (!td_read)
+ continue;
+ tin = container_of(td_read, struct ctf_trace, parent);
+ /* For each stream_class in the trace */
+ for (j = 0; j < tin->streams->len; j++) {
+ struct ctf_stream_declaration *stream_class;
+
+ stream_class = g_ptr_array_index(tin->streams, j);
+ if (!stream_class)
+ continue;
+ ret = find_max_timestamp_ctf_stream_class(stream_class,
+ cfsp, &max_timestamp);
+ if (ret > 0)
+ goto end;
+ if (ret == 0)
+ found = 1;
+ assert(ret == EOF || ret == 0);
+ }
+ }
+ /*
+ * Now we know in which file stream the last event is located,
+ * and we know its timestamp.
+ */
+ if (!found) {
+ ret = EOF;
+ } else {
+ ret = seek_file_stream_by_timestamp(*cfsp, max_timestamp);
+ assert(ret == 0);
+ }
+end:
+ return ret;
+}
+
+int bt_iter_set_pos(struct bt_iter *iter, const struct bt_iter_pos *iter_pos)
+{
+ struct trace_collection *tc;
+ int i, ret;
+
+ if (!iter || !iter_pos)
+ return -EINVAL;
+
+ switch (iter_pos->type) {
+ case BT_SEEK_RESTORE:
+ if (!iter_pos->u.restore)
+ return -EINVAL;
+
+ heap_free(iter->stream_heap);
+ ret = heap_init(iter->stream_heap, 0, stream_compare);
+ if (ret < 0)
+ goto error_heap_init;
+
+ for (i = 0; i < iter_pos->u.restore->stream_saved_pos->len;
+ i++) {
+ struct stream_saved_pos *saved_pos;
+ struct ctf_stream_pos *stream_pos;
+ struct ctf_stream_definition *stream;
+
+ saved_pos = &g_array_index(
+ iter_pos->u.restore->stream_saved_pos,
+ struct stream_saved_pos, i);
+ stream = &saved_pos->file_stream->parent;
+ stream_pos = &saved_pos->file_stream->pos;
+
+ stream_pos->packet_seek(&stream_pos->parent,
+ saved_pos->cur_index, SEEK_SET);
+
+ /*
+ * the timestamp needs to be restored after
+ * packet_seek, because this function resets
+ * the timestamp to the beginning of the packet
+ */
+ stream->real_timestamp = saved_pos->current_real_timestamp;
+ stream->cycles_timestamp = saved_pos->current_cycles_timestamp;
+ stream_pos->offset = saved_pos->offset;
+ stream_pos->last_offset = LAST_OFFSET_POISON;
+
+ stream->prev_real_timestamp = 0;
+ stream->prev_real_timestamp_end = 0;
+ stream->prev_cycles_timestamp = 0;
+ stream->prev_cycles_timestamp_end = 0;
+
+ printf_debug("restored to cur_index = %" PRId64 " and "
+ "offset = %" PRId64 ", timestamp = %" PRIu64 "\n",
+ stream_pos->cur_index,
+ stream_pos->offset, stream->real_timestamp);
+
+ ret = stream_read_event(saved_pos->file_stream);
+ if (ret != 0) {
+ goto error;
+ }
+
+ /* Add to heap */
+ ret = heap_insert(iter->stream_heap,
+ saved_pos->file_stream);
+ if (ret)
+ goto error;
+ }
+ return 0;
+ case BT_SEEK_TIME:
+ tc = iter->ctx->tc;
+
+ heap_free(iter->stream_heap);
+ ret = heap_init(iter->stream_heap, 0, stream_compare);
+ if (ret < 0)
+ goto error_heap_init;
+
+ /* for each trace in the trace_collection */
+ for (i = 0; i < tc->array->len; i++) {
+ struct ctf_trace *tin;
+ struct trace_descriptor *td_read;
+
+ td_read = g_ptr_array_index(tc->array, i);
+ if (!td_read)
+ continue;
+ tin = container_of(td_read, struct ctf_trace, parent);
+
+ ret = seek_ctf_trace_by_timestamp(tin,
+ iter_pos->u.seek_time,
+ iter->stream_heap);
+ /*
+ * Positive errors are failure. Negative value
+ * is EOF (for which we continue with other
+ * traces). 0 is success. Note: on EOF, it just
+ * means that no stream has been added to the
+ * iterator for that trace, which is fine.
+ */
+ if (ret != 0 && ret != EOF)
+ goto error;
+ }
+ return 0;
+ case BT_SEEK_BEGIN:
+ tc = iter->ctx->tc;
+ heap_free(iter->stream_heap);
+ ret = heap_init(iter->stream_heap, 0, stream_compare);
+ if (ret < 0)
+ goto error_heap_init;
+
+ for (i = 0; i < tc->array->len; i++) {
+ struct ctf_trace *tin;
+ struct trace_descriptor *td_read;
+ int stream_id;
+
+ td_read = g_ptr_array_index(tc->array, i);
+ if (!td_read)
+ continue;
+ tin = container_of(td_read, struct ctf_trace, parent);
+
+ /* Populate heap with each stream */
+ for (stream_id = 0; stream_id < tin->streams->len;
+ stream_id++) {
+ struct ctf_stream_declaration *stream;
+ int filenr;
+
+ stream = g_ptr_array_index(tin->streams,
+ stream_id);
+ if (!stream)
+ continue;
+ for (filenr = 0; filenr < stream->streams->len;
+ filenr++) {
+ struct ctf_file_stream *file_stream;
+ file_stream = g_ptr_array_index(
+ stream->streams,
+ filenr);
+ if (!file_stream)
+ continue;
+ ret = babeltrace_filestream_seek(
+ file_stream, iter_pos,
+ stream_id);
+ if (ret != 0 && ret != EOF) {
+ goto error;
+ }
+ if (ret == EOF) {
+ /* Do not add EOF streams */
+ continue;
+ }
+ ret = heap_insert(iter->stream_heap, file_stream);
+ if (ret)
+ goto error;
+ }
+ }
+ }
+ break;
+ case BT_SEEK_LAST:
+ {
+ struct ctf_file_stream *cfs = NULL;
+
+ tc = iter->ctx->tc;
+ ret = seek_last_ctf_trace_collection(tc, &cfs);
+ if (ret != 0 || !cfs)
+ goto error;
+ /* remove all streams from the heap */
+ heap_free(iter->stream_heap);
+ /* Create a new empty heap */
+ ret = heap_init(iter->stream_heap, 0, stream_compare);
+ if (ret < 0)
+ goto error;
+ /* Insert the stream that contains the last event */
+ ret = heap_insert(iter->stream_heap, cfs);
+ if (ret)
+ goto error;
+ break;
+ }
+ default:
+ /* not implemented */
+ return -EINVAL;
+ }
+
+ return 0;
+
+error:
+ heap_free(iter->stream_heap);
+error_heap_init:
+ if (heap_init(iter->stream_heap, 0, stream_compare) < 0) {
+ heap_free(iter->stream_heap);
+ g_free(iter->stream_heap);
+ iter->stream_heap = NULL;
+ ret = -ENOMEM;
+ }
+
+ return ret;
+}
+
+struct bt_iter_pos *bt_iter_get_pos(struct bt_iter *iter)
+{
+ struct bt_iter_pos *pos;
+ struct trace_collection *tc;
+ struct ctf_file_stream *file_stream = NULL, *removed;
+ struct ptr_heap iter_heap_copy;
+ int ret;
+
+ if (!iter)
+ return NULL;
+
+ tc = iter->ctx->tc;
+ pos = g_new0(struct bt_iter_pos, 1);
+ pos->type = BT_SEEK_RESTORE;
+ pos->u.restore = g_new0(struct bt_saved_pos, 1);
+ pos->u.restore->tc = tc;
+ pos->u.restore->stream_saved_pos = g_array_new(FALSE, TRUE,
+ sizeof(struct stream_saved_pos));
+ if (!pos->u.restore->stream_saved_pos)
+ goto error;
+
+ ret = heap_copy(&iter_heap_copy, iter->stream_heap);
+ if (ret < 0)
+ goto error_heap;
+
+ /* iterate over each stream in the heap */
+ file_stream = heap_maximum(&iter_heap_copy);
+ while (file_stream != NULL) {
+ struct stream_saved_pos saved_pos;
+
+ assert(file_stream->pos.last_offset != LAST_OFFSET_POISON);
+ saved_pos.offset = file_stream->pos.last_offset;
+ saved_pos.file_stream = file_stream;
+ saved_pos.cur_index = file_stream->pos.cur_index;
+
+ saved_pos.current_real_timestamp = file_stream->parent.real_timestamp;
+ saved_pos.current_cycles_timestamp = file_stream->parent.cycles_timestamp;
+
+ g_array_append_val(
+ pos->u.restore->stream_saved_pos,
+ saved_pos);
+
+ printf_debug("stream : %" PRIu64 ", cur_index : %zd, "
+ "offset : %zd, "
+ "timestamp = %" PRIu64 "\n",
+ file_stream->parent.stream_id,
+ saved_pos.cur_index, saved_pos.offset,
+ saved_pos.current_real_timestamp);
+
+ /* remove the stream from the heap copy */
+ removed = heap_remove(&iter_heap_copy);
+ assert(removed == file_stream);
+
+ file_stream = heap_maximum(&iter_heap_copy);
+ }
+ heap_free(&iter_heap_copy);
+ return pos;
+
+error_heap:
+ g_array_free(pos->u.restore->stream_saved_pos, TRUE);
+error:
+ g_free(pos);
+ return NULL;
+}
+
+struct bt_iter_pos *bt_iter_create_time_pos(struct bt_iter *iter,
+ uint64_t timestamp)
+{
+ struct bt_iter_pos *pos;
+
+ if (!iter)
+ return NULL;
+
+ pos = g_new0(struct bt_iter_pos, 1);
+ pos->type = BT_SEEK_TIME;
+ pos->u.seek_time = timestamp;
+ return pos;
+}
+