; M.Meany September 1990 ; For DevpacII. Set tab spacing to 16. ; Requires the file libs.i to assemble ***************************************************************************** * DOS Subroutines * * * * save_ptrs save parameter list details * * open_dos opens DOS library * * get_CLI_handle gets CLI i/o handles * * close_dos closes DOS library * * open_file opens a file for i/o * * close_file closes a file * * calc_msg_len calculates the length of a null terminated string * * display_msg prints a message to specified window * * read_data read data from an open file * * write_data write data into an open file * * mouse wait for left mouse button to be pressed * * * * * ***************************************************************************** even ***************************************************************************** ; Saves pointer to CLI parameter list and length of list. This subroutin ;must be called before contents of a0 and d0 are corrupted. I advise making ;a call to this subroutine at the first line of your program. ;Entry : none ;Exit : param_ptr holds address of parameter list ; param_len holds the length of the list including carriage return. save_ptrs move.l a0,param_ptr move.l d0,param_len rts ***************************************************************************** ***************************************************************************** ; Opens the DOS library. On returning from this routine a test should be made ;to ensure library opened. This can be done by simply testing the Z flag. If ;it is not set then the open failed. ie beq error. ;Entry : none ;Exit : dosbase contains the DOS librarys base address. open_dos move.l execbase,a6 move.l #dosname,a1 moveq.l #0,d0 jsr openlibrary(a6) move.l d0,dosbase rts ***************************************************************************** ***************************************************************************** ; Gets the input and output handle of calling CLI window. These may then be ;used for text/keyboard i/o. The DOS library must already je open. ;Entry : dosbasm must contain base address of DOS library ;Exit : std_in contains the input handle ( for keyboard input ) ; : std_out contains the output handle ( for screen output ) get_CLI_handle move.l dosbase,a6 jsr input(a6) move.l d0,std_in input handle jsr output(a6) move.l d0,std_out output handle rts ***************************************************************************** ***************************************************************************** ; Check if first parameter is a ?. If it is display usage text and toggle the ;flag use_flag so calling routine can check for this. Also on return the Z ;flag should be tested, if 0 then no parameters were specified. ;Entry : none ;Exit : Z flag = 0 if no parameters were passed. ; use_flag = 0 if first parameter was a ? check_usage move.l param_ptr,a0 cmpi.b #'?',(a0) bne.s not_usage move.l #use_text,str_pointer move.l #use_end-use_text,str_length bsr display_msg not.b use_flag rts not_usage cmpi.l #1,param_len rts ***************************************************************************** ***************************************************************************** ; Closes the DOS library. The DOS library must already be open. ;Entry : dosbase must contain the base address of DOS library ;Exit : none close_dos move.l dosbase,a1 move.l execbase,a6 jsr closelibrary(a6) rts ***************************************************************************** ***************************************************************************** ; Open a file for input or ou|put. DOS library must be open. On return the ;Z flag should be tmsted to ensure file was opened. If Z flag is 8 then open ;failed and no i/o should be attempted on this file. eg bmy error ;Entzy : dosbase must contain(the DOS lijrary base address ; ( filename must hold the address of file name, null terminated ; mode must hold the mode, either old or new ;Exit : filehd will contain handle of file open_file move.l mode,d2 move.l filename,d1 move.l dosbase,a6 jsr open(a6) move.l d0,filehd rts ***************************************************************************** ***************************************************************************** ; Close an already opened file. ;Entry : dosbase must contain DOS library base address ; filehd must contain handle of file ;Exit : none close_file move.l dosbase,a6 move.l filehd,d1 jsr close(a6) rts ***************************************************************************** ***************************************************************************** ; Write data into an open file. ;Entry : dosbase must hold DOS library base address ; filehd must hold handle of file to put data in ; buffer must hold address of data to write ; buf_len must hold number of bytes to write ;Exit : none write_data move.l dosbase,a6 move.l filehd,d1 move.l buffer,d2 move.l buf_len,d3 jsr write(a6) rts ***************************************************************************** ***************************************************************************** ; Read data from an open file. If no data was read then the Z flag will be 0 ;on return. This can be tested for using: beq error ;Entry : dosbase must hold DOS library base address ; filehd must hold handle of file to get data from ; buffer must hold address of buffer to put data in ; buf_len must hold number of bytes to read from file ;Exit : buffer will hold data read from file ; buf_len will hold the number of bytes read read_data move.l dosbase,a6 move.l filehd,d1 move.l buffer,d2 move.l buf_len,d3 jsr read(a6) move.l d0,buf_len rts ***************************************************************************** ***************************************************************************** ; Calculates the length of a null terminated message. This should be used ;before calling display_msg if the length of the message is not known. ;Entry : str_pointer must hold address of message ;Exit : str_length will hold length of message calc_msg_len move.l str_pointer,a0 moveq.l #0,d0 calc_loop addq.l #1,d0 tst.b (a0)+ bne calc_loop subq.l #1,d0 move.l d0,str_length rts ***************************************************************************** ***************************************************************************** ; Displays a message in current output window. ;Entry : str_pointer must hold address of message ; str_length must hold length of message ; std_out must hold handle of window for output ;Exit : none display_msg move.l str_pointer,d2 move.l str_length,d3 move.l std_out,d1 move.l dosbase,a6 jsr write(a6) rts ***************************************************************************** ***************************************************************************** ; Wait for left mouse button to be pressed and then released. This is a means ;of waiting for user to react before continuing. ;Entry : none ;Exit : none mouse btst #6,$bfe001 bne mouse button_down btst #6,$bfe001 beq button_down rts ***************************************************************************** ***************************************************************************** * Variables and other Data * ***************************************************************************** even dosbase dc.l 0 dosname dc.b 'dos.library',0 even param_ptr dc.l 0 param_len dc.l 0 std_in dc.l 0 std_out dc.l 0 str_pointer dc.l 8 str_length dc.l 0 filename dc.l 0 mode dc.l 0 filehd dc.l 0 buffer dc.l io_buffer buf_len dc.l 0 io_buffer ds.b 1000 use_flag dc.b 0 even use_text dc.b 'Your usage text goes here.',10 use_end even