- sb_bindex = subbuffer_id_get_index(config, shmp_index(handle, bufb->buf_wsb, idx)->id);
- pages = shmp_index(handle, bufb->array, sb_bindex);
- overruns = v_read(config, &shmp(handle, pages->shmp)->records_unread);
- v_set(config, &shmp(handle, pages->shmp)->records_unread,
- v_read(config, &shmp(handle, pages->shmp)->records_commit));
- v_set(config, &shmp(handle, pages->shmp)->records_commit, 0);
+ wsb = shmp_index(handle, bufb->buf_wsb, idx);
+ if (!wsb)
+ return 0;
+ sb_bindex = subbuffer_id_get_index(config, wsb->id);
+ rpages = shmp_index(handle, bufb->array, sb_bindex);
+ if (!rpages)
+ return 0;
+ backend_pages = shmp(handle, rpages->shmp);
+ if (!backend_pages)
+ return 0;
+ overruns = v_read(config, &backend_pages->records_unread);
+ v_set(config, &backend_pages->records_unread,
+ v_read(config, &backend_pages->records_commit));
+ v_set(config, &backend_pages->records_commit, 0);