RHUWM_INITIAL_LOAD_PROTOCOL is a standard ABAP report available within your SAP system (depending on your version and release level). Below is the standard documentation available for this report and a few details of other objects it interacts with such as tables, function modules, includes etc. If you would like to see the full code listing simply enter RHUWM_INITIAL_LOAD_PROTOCOL into the relevant SAP transaction such as SE38 or SE80
HUWM_LOAD_PROT select * from HUWM_LOAD_PROT into table gt_protocol. "#EC CI_NOWHERE
HUWM_LOAD_PROT select * from huwm_load_prot into table gt_protocol where posted = ' '.
HUWM_LOAD_PROT select * from huwm_load_prot into table gt_prot_wm where posted = 'X'.
HU_IDL_PROTOCOL_DISPLAY CALL FUNCTION 'HU_IDL_PROTOCOL_DISPLAY' exporting it_protocol = gt_protocol exceptions error = 1 others = 99.
HU_IDL_PROTOCOL_DISPLAY CALL FUNCTION 'HU_IDL_PROTOCOL_DISPLAY' exporting it_protocol = gt_prot_wm exceptions error = 1 others = 99.
HU_INITIAL_DATA_LOAD CALL FUNCTION 'HU_INITIAL_DATA_LOAD' EXPORTING if_prot = 'X' IF_POST_IM = lp_d IT_INITIAL_DATA = gt_prot_init importing ET_PROTOCOL = gt_protocol.
HU_IDL_WM CALL FUNCTION 'HU_IDL_WM' exporting if_prot = 'X' CHANGING CT_LOAD = gt_prot_wm.