+struct ctf_fs_ds_group_medops_data {
+ /* Weak, set once at creation time. */
+ struct ctf_fs_ds_file_group *ds_file_group;
+
+ /*
+ * Index (as in element rank) of the index entry of ds_file_groups'
+ * index we will read next (so, the one after the one we are reading
+ * right now).
+ */
+ guint next_index_entry_index;
+
+ /*
+ * File we are currently reading. Changes whenever we switch to
+ * reading another data file.
+ *
+ * Owned by this.
+ */
+ struct ctf_fs_ds_file *file;
+
+ /* Weak, for context / logging / appending causes. */
+ bt_self_message_iterator *self_msg_iter;
+ bt_logging_level log_level;
+};
+
+static
+enum ctf_msg_iter_medium_status medop_group_request_bytes(
+ size_t request_sz,
+ uint8_t **buffer_addr,
+ size_t *buffer_sz,
+ void *void_data)
+{
+ struct ctf_fs_ds_group_medops_data *data = void_data;
+
+ /* Return bytes from the current file. */
+ return medop_request_bytes(request_sz, buffer_addr, buffer_sz, data->file);
+}
+
+static
+bt_stream *medop_group_borrow_stream(
+ bt_stream_class *stream_class,
+ int64_t stream_id,
+ void *void_data)
+{
+ struct ctf_fs_ds_group_medops_data *data = void_data;
+
+ return medop_borrow_stream(stream_class, stream_id, data->file);
+}
+
+/*
+ * Set `data->file` to prepare it to read the packet described
+ * by `index_entry`.
+ */
+
+static
+enum ctf_msg_iter_medium_status ctf_fs_ds_group_medops_set_file(
+ struct ctf_fs_ds_group_medops_data *data,
+ struct ctf_fs_ds_index_entry *index_entry,
+ bt_self_message_iterator *self_msg_iter,
+ bt_logging_level log_level)
+{
+ enum ctf_msg_iter_medium_status status;
+
+ BT_ASSERT(data);
+ BT_ASSERT(index_entry);
+
+ /* Check if that file is already the one mapped. */
+ if (!data->file || strcmp(index_entry->path, data->file->file->path->str) != 0) {
+ /* Destroy the previously used file. */
+ ctf_fs_ds_file_destroy(data->file);
+
+ /* Create the new file. */
+ data->file = ctf_fs_ds_file_create(
+ data->ds_file_group->ctf_fs_trace,
+ self_msg_iter,
+ data->ds_file_group->stream,
+ index_entry->path,
+ log_level);
+ if (!data->file) {
+ BT_MSG_ITER_LOGE_APPEND_CAUSE(self_msg_iter,
+ "failed to create ctf_fs_ds_file.");
+ status = CTF_MSG_ITER_MEDIUM_STATUS_ERROR;
+ goto end;
+ }
+ }
+
+ /*
+ * Ensure the right portion of the file will be returned on the next
+ * request_bytes call.
+ */
+ status = ds_file_mmap(data->file, index_entry->offset);
+ if (status != CTF_MSG_ITER_MEDIUM_STATUS_OK) {
+ goto end;
+ }
+
+ status = CTF_MSG_ITER_MEDIUM_STATUS_OK;
+
+end:
+ return status;
+}
+
+static
+enum ctf_msg_iter_medium_status medop_group_switch_packet(void *void_data)
+{
+ struct ctf_fs_ds_group_medops_data *data = void_data;
+ struct ctf_fs_ds_index_entry *index_entry;
+ enum ctf_msg_iter_medium_status status;
+
+ /* If we have gone through all index entries, we are done. */
+ if (data->next_index_entry_index >=
+ data->ds_file_group->index->entries->len) {
+ status = CTF_MSG_ITER_MEDIUM_STATUS_EOF;
+ goto end;
+ }
+
+ /*
+ * Otherwise, look up the next index entry / packet and prepare it
+ * for reading.
+ */
+ index_entry = g_ptr_array_index(
+ data->ds_file_group->index->entries,
+ data->next_index_entry_index);
+
+ status = ctf_fs_ds_group_medops_set_file(
+ data, index_entry, data->self_msg_iter, data->log_level);
+ if (status != CTF_MSG_ITER_MEDIUM_STATUS_OK) {
+ goto end;
+ }
+
+ data->next_index_entry_index++;
+
+ status = CTF_MSG_ITER_MEDIUM_STATUS_OK;
+end:
+ return status;
+}
+
+BT_HIDDEN
+void ctf_fs_ds_group_medops_data_destroy(
+ struct ctf_fs_ds_group_medops_data *data)
+{
+ if (!data) {
+ goto end;
+ }
+
+ ctf_fs_ds_file_destroy(data->file);
+
+ g_free(data);
+
+end:
+ return;
+}
+
+enum ctf_msg_iter_medium_status ctf_fs_ds_group_medops_data_create(
+ struct ctf_fs_ds_file_group *ds_file_group,
+ bt_self_message_iterator *self_msg_iter,
+ bt_logging_level log_level,
+ struct ctf_fs_ds_group_medops_data **out)
+{
+ struct ctf_fs_ds_group_medops_data *data;
+ enum ctf_msg_iter_medium_status status;
+
+ BT_ASSERT(self_msg_iter);
+ BT_ASSERT(ds_file_group);
+ BT_ASSERT(ds_file_group->index);
+ BT_ASSERT(ds_file_group->index->entries->len > 0);
+
+ data = g_new0(struct ctf_fs_ds_group_medops_data, 1);
+ if (!data) {
+ BT_MSG_ITER_LOGE_APPEND_CAUSE(self_msg_iter,
+ "Failed to allocate a struct ctf_fs_ds_group_medops_data");
+ status = CTF_MSG_ITER_MEDIUM_STATUS_MEMORY_ERROR;
+ goto error;
+ }
+
+ data->ds_file_group = ds_file_group;
+ data->self_msg_iter = self_msg_iter;
+ data->log_level = log_level;
+
+ /*
+ * No need to prepare the first file. ctf_msg_iter will call
+ * switch_packet before reading the first packet, it will be
+ * done then.
+ */
+
+ *out = data;
+ status = CTF_MSG_ITER_MEDIUM_STATUS_OK;
+ goto end;
+
+error:
+ ctf_fs_ds_group_medops_data_destroy(data);
+
+end:
+ return status;
+}
+
+void ctf_fs_ds_group_medops_data_reset(struct ctf_fs_ds_group_medops_data *data)
+{
+ data->next_index_entry_index = 0;
+}
+
+struct ctf_msg_iter_medium_ops ctf_fs_ds_group_medops = {
+ .request_bytes = medop_group_request_bytes,
+ .borrow_stream = medop_group_borrow_stream,
+ .switch_packet = medop_group_switch_packet,
+
+ /*
+ * We don't support seeking using this medops. It would probably be
+ * possible, but it's not needed at the moment.
+ */
+ .seek = NULL,
+};
+