; **************************************************************************** ; ; UNIXBOOT.ASM (Only for 1.44 MB floppy disks) ; ---------------------------------------------------------------------------- ; ; RETRO UNIX 8086 (Retro Unix == Turkish Rational Unix) ; Operating System Project (v0.1) by ERDOGAN TAN (Beginning: 11/07/2012) ; 1.44 MB Floppy Disk ; Bootable Unix (RUFS) File System - Boot File Configuration Code ; ; [ Last Modification: 09/07/2013 ] ; ; Derivation from UNIX Operating System (v1.0 for PDP-11) ; (Original) Source Code by Ken Thompson (1971-1972) ; ; ; ; Derived from (Only for 1.44 MB floppy disks) ; SINGLIX FS startup file configuration utility, BOOTFILE.ASM (21/02/2010) ; ; **************************************************************************** bsFSystemID equ 2 ; 'RUFS' bsVolumeSerial equ 6 ; (4 bytes) bsFDSign equ 10 ; 'fd' bsDriveNumber equ 12 ; fd0 or fd1 (0 or 1) bsReserved equ 13 ; 0 (512 bytes per sector) bsSecPerTrack equ 14 ; 18 (9 or 15) bsHeads equ 15 ; 2 bsTracks equ 16 ; 80 bs_BF_inode_number equ 18 ; 0 or Boot/Startup File I-Number bsInfoEndsign equ 20 ; '@' ROOT_DIR_INODE_NUMBER equ 41 ; DTA (PSP+80h= Offset 128) DTA_Time equ 150 ; PSP+22 DTA_Date equ 152 ; PSP 24 DTA_FileSize equ 154 ; PSP + 26 DTA_FileName equ 158 ; PSP + 30 err_INVALIDDATA equ 100h err_NOFREEBLOCK equ 200h i_flags equ 001Eh .8086 UNIXBOOT SEGMENT PUBLIC 'CODE' assume cs:UNIXBOOT,ds:UNIXBOOT,es:UNIXBOOT,ss:UNIXBOOT org 100h START_CODE: proc_start proc near ; 30/11/2012 ; 18/11/2012 ; 31/10/2012 mov bx, SizeOfFile+100 add bx, 15 shr bx, 1 shr bx, 1 shr bx, 1 shr bx, 1 mov ah, 4Ah ; modify memory allocation ;push cs ;pop es int 21h ;- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ; see if drive specified ;- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - mov si, offset 80h ; PSP command tail mov cl, byte ptr [SI] or cl, cl jz loc_unix_welcome ; jump if zero loc_get_args: inc si mov al, byte ptr [SI] cmp al, ' ' ; is it SPACE ? jne short loc_check_fd_name dec cl jnz short loc_get_args jmp loc_unix_welcome loc_check_fd_name: cmp al, "f" jne loc_unix_welcome inc si mov al, byte ptr [SI] cmp al, "d" jne short loc_unix_welcome inc si mov al, byte ptr [SI] cmp al, '0' jb short loc_unix_welcome cmp al, '1' ja short loc_unix_welcome mov byte ptr [UNIX_FD_Number], al mov dl, al sub dl, '0' mov byte ptr [PhysicalDriveNumber], dl load_boot_sector: ; 11/11/2012 ; input -> dl = drive number xor ah,ah int 13h jc short loc_drv_read_error load_boot_sector_ok: mov bx, offset BSBuffer mov ax,0202h ; Read boot sector & super block, 17/11/2012 mov cx,1 xor dh,dh int 13h jc short loc_drv_read_error cmp word ptr [BX]+510, 0AA55h jne short loc_not_fd_rufs cmp word ptr [BX]+bsFSystemID, 'UR' jne short loc_not_fd_rufs cmp word ptr [BX]+bsFSystemID+2, 'SF' je short loc_check_fd_sign loc_not_fd_rufs: mov si, offset msg_Not_Unix_FS jmp short @f loc_check_fd_sign: cmp word ptr [BX]+bsFDSign, 'df' jne short loc_not_fd_rufs ;- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ; Write message ;- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - loc_dywtw_question:: mov si, offset Msg_DoYouWantToWrite call UNIX_PRINTMSG mov si, offset UNIX_FD_Name call UNIX_PRINTMSG loc_print_yes_no: mov si, offset msg_yes_no call UNIX_PRINTMSG loc_ask_for_write_sf: xor ax, ax int 16h ; wait for keyboard command cmp al, 'C'-40h je short @f cmp al, 27 je short @f and al, 0DFh cmp al, 'Y' ; Yes? je short loc_yes_write_sf ; write cmp al, 'N' ; No? jne short loc_ask_for_write_sf loc_no_write_sf: mov si, offset msg_No jmp short @f loc_unix_welcome: mov si, offset UNIX_Welcome @@: call UNIX_PRINTMSG int 20h int 19h loc_drv_read_error: mov si, offset msg_unix_drv_read_error jmp short @b ;- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ; get drive parameters ;- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - loc_yes_write_sf: mov si, offset msg_YES call UNIX_PRINTMSG loc_load_fs_boot_sector: mov si, offset BSBuffer loc_check_current_sbf_adress: mov ax, word ptr [SI]+bs_BF_inode_Number or ax, ax jnz short loc_startup_file_exists loc_dos_sf_name_input: mov si, offset Msg_DosFile_Name call UNIX_PRINTMSG mov al, 64 ; DOS file name (max.) length (for full path name) call proc_rw_char jc short pass_write_file_name_chr0 mov di, offset StartupFile_Name cmp byte ptr [SI], 20h jna short pass_write_file_name_chr0 mov cx, 64 loc_write_file_name_chr0: lodsb cmp al, 20h jnb short loc_write_file_name_chr1 pass_write_file_name_chr0: mov byte ptr [DI], 0 inc di loop pass_write_file_name_chr0 jmp short loc_find_dos_file loc_write_file_name_chr1: mov byte ptr [DI], al inc di loop loc_write_file_name_chr0 loc_find_dos_file: mov si, offset UNIX_CRLF call UNIX_PRINTMSG mov dx, offset StartupFile_Name mov cx, 27h ; File Attributes mov ah, 4Eh ; MS Dos Function = Find First File int 21h jnc loc_open_dos_file_1 jmp loc_dos_file_notfound loc_startup_file_exists: ; AX = Startup/Boot File I-Number ; ; 25/11/2012 ;mov bx, ax ;;mov cx, 9 ;mov cx, 4 ;mov di, offset Boot_File_Name ;xor al, al ;;xor ax, ax ;rep stosb ;;rep stosw ; ax= i-number call find_bfn jnc short loc_move_bfn_1 and ax, ax jnz short loc_drv_read_error ;mov si, offset BSBuffer ;mov word ptr [SI]+bs_BF_inode_Number, ax ; jmp short loc_dos_sf_name_input loc_move_bfn_1: mov si, offset u_dirbuf + 2 mov di, offset Boot_File_Name mov cx, 8 loc_move_bfn_2: lodsb and al, al jnz short @f mov byte ptr [DI], al ; 0 ;cmp al, 20h ;;jb short loc_startup_file_exists_msg ;;ja short @f ;mov byte ptr [DI], 0 jmp short loc_startup_file_exists_msg @@: stosb loop loc_move_bfn_2 loc_startup_file_exists_msg: mov si, offset msg_Startup_file_exists call UNIX_PRINTMSG loc_startup_file_exist_select_option: ; 25/11/2012 xor ah, ah int 16h cmp al, 1Bh je loc_exit cmp al, 0Dh jne short loc_check_startupfile_delete_decision call proc_display_startupfile_info mov si, offset msg_please_select_an_option call UNIX_PRINTMSG jmp short loc_startup_file_exist_select_option loc_check_startupfile_delete_decision: cmp ah, 53h jne short loc_startup_file_exist_select_option loc_delete_decision_second_stage: ; 01/12/2012 mov si, offset msg_Delete_Startup_File call UNIX_PRINTMSG mov bx, offset BSBuffer xor cx, cx loc_delete_startup_file_input: xor ah, ah int 16h cmp al, 1Bh je loc_exit cmp al, 0Dh je short loc_reset_startupfile_configuration cmp ah, 53h jne short loc_delete_startup_file_input loc_delete_startup_file: mov ax, word ptr [BX]+bs_BF_inode_Number mov word ptr [BX]+bs_BF_inode_Number, cx push ax mov si, offset Msg_deleting_sf call UNIX_PRINTMSG pop ax call unlink ; delete file jc loc_unix_fd_write_error jmp loc_update_boot_sector_and_sb loc_reset_startupfile_configuration: mov word ptr [bx]+bs_BF_inode_Number, cx mov ax,0301h ; Write boot sector ;mov cx,1 inc cx xor dh,dh mov dl, byte ptr [PhysicalDriveNumber] int 13h jc loc_unix_fd_write_error mov si, offset msg_sf_configuration_reset_ok call UNIX_PRINTMSG jmp loc_exit loc_open_dos_file_1: mov si, DTA_FileName mov di, offset StartupFile_Name mov cx, 64 loc_copy_found_file_name_chr0: lodsb cmp al, 20h jnb short loc_copy_found_file_name_chr1 pass_copy_found_file_name_chr0: mov byte ptr [DI], 0 inc di loop pass_copy_found_file_name_chr0 jmp short loc_set_startupfile_inode loc_copy_found_file_name_chr1: mov byte ptr [DI], al inc di loop loc_copy_found_file_name_chr0 loc_set_startupfile_inode: ; 30/11/2012 BugFix ; ; DOS TimeStamp -> ; Bits 0-4 seconds/2 ; Bits 5-10 minute ; Bits 11-15 hour ; DOS DateStamp -> ; Bits 0-4 (16-20) day ; Bits 5-8 (21-24) month ; Bits 9-15 (25-31) year ; ; 25/11/2012 modification ;mov word ptr [inode_flgs], 801Eh ; 1000000000011110b ;mov byte ptr [inode_nlnks], 1 ;mov byte ptr [inode_uid], 0 ;xor ax, ax ;mov cx, 8 ;mov di, offset inode_dskp ;rep stosw mov si, DTA_FileSize mov ax, word ptr [SI] mov dx, word ptr [SI]+2 or dx, dx jnz loc_very_big_startupfile_size mov word ptr [inode_Size], ax mov si, DTA_Date mov ax, word ptr [SI] push ax and ax, 00011111b ; Day Mask mov word ptr [day], ax pop ax mov cl, 5 shr ax, cl ; shift right 5 times push ax and ax, 00001111b ; Month Mask mov word ptr [month], ax pop ax mov cl, 4 shr ax, cl ;and ax, 01111111b ; Result = Year - 1980 add ax, 1980 mov word ptr [year], ax mov si, DTA_Time mov ax, word ptr [SI] push ax and ax, 0000011111b ; Second Mask shl al, 1 mov word ptr [second], ax pop ax mov cl, 5 shr ax, cl ; shift right 5 times push ax and ax, 0000111111b ; Minute Mask mov word ptr [minute], ax pop ax mov cl, 6 ; shift right 6 times shr ax, cl ; (6+5=11) mov word ptr [hour], ax ; ax = hours call convert_to_epoch mov word ptr [bf_make_datetime], ax mov word ptr [bf_make_datetime]+2, dx loc_open_dos_file_2: mov dx, offset StartupFile_Name mov ah, 3Dh ; MS Dos Function = Open File xor al, al int 21h jnc short loc_save_filehandle loc_dos_file_notfound: mov si, offset Msg_File_Not_Found call UNIX_PRINTMSG jmp loc_exit loc_very_big_startupfile_size: mov si, offset msg_very_big_startup_file_size call UNIX_PRINTMSG jmp loc_exit loc_save_filehandle: mov word ptr [FileHandle], ax loc_display_startup_file_name: mov si, offset Msg_StartupFile_Name call UNIX_PRINTMSG ;mov ah, 03h ;;xor bh, bh ;int 10h ;;push dx ;mov si, offset StartupFile_Name ;call UNIX_PRINTMSG ;;pop dx ;mov ah, 02h ;;xor bh, bh ;int 10h mov al, 8 ; Boot file name (max.) length (unix v1 fs) call proc_rw_char jc loc_exit cmp byte ptr [SI], 20h jna loc_exit mov di, offset BOOT_FILE_NAME mov word ptr [u_namep], di ; 11/11/2012 mov cx, 8 loc_rename_file_name_chr0: lodsb cmp al, 20h jnb short loc_rename_file_name_chr1 pass_rename_file_name_chr0: mov byte ptr [DI], 0 inc di loop pass_rename_file_name_chr0 jmp short loc_check_startupfile_name loc_rename_file_name_chr1: mov byte ptr [DI], al inc di loop loc_rename_file_name_chr0 loc_check_startupfile_name: mov si, offset UNIX_CRLF call UNIX_PRINTMSG call name_i ;11/11/2012 jc short loc_check_namei_error ; 1/12/2012 ; 1/12/2012 push ax ; i-number of file mov si, offset msg_overwrite_question1 call UNIX_PRINTMSG mov si, offset BOOT_FILE_NAME call UNIX_PRINTMSG mov si, offset msg_overwrite_question2 call UNIX_PRINTMSG mov si, offset msg_yes_no call UNIX_PRINTMSG loc_ask_for_overwrite_f: xor ax, ax int 16h ; wait for keyboard command cmp al, 'C'-40h je short @f cmp al, 27 je short @f and al, 0DFh cmp al, 'Y' ; Yes? je short loc_yes_overwrite_f ; write cmp al, 'N' ; No? jne short loc_ask_for_overwrite_f loc_no_ovewrite_f: pop ax mov si, offset msg_No @@: mov ah, 3Eh ; Close File mov bx, word ptr [FileHandle] int 21h jmp loc_exit loc_yes_overwrite_f: mov si, offset msg_YES call UNIX_PRINTMSG mov si, offset UNIX_CRLF call UNIX_PRINTMSG pop ax ; i-number of file call itrunc ; truncate file jc short loc_unix_fd_write_error mov si, offset Msg_writing_sf call UNIX_PRINTMSG mov ax, word ptr [ii] jmp short @f loc_check_namei_error: cmp ah, 0FFh jne short loc_close_dos_sf ; jb / cf = 1 loc_write_SF: mov si, offset Msg_writing_sf call UNIX_PRINTMSG loc_make_inode: mov ax, i_flags ; Boot file flags, 001Eh call mak_nod jc short loc_unix_fd_write_error @@: mov bx, offset BSBuffer mov word ptr [BX]+ bs_BF_inode_Number, ax ; i-number xor ax, ax mov word ptr [u_off], ax ;mov word ptr [u_fofp], offset u_off loc_read_dos_sf: mov ah, 3Fh ; Read File mov cx, 512 mov dx, offset ReadBUFFER mov bx, word ptr [FileHandle] int 21h jc short loc_close_dos_sf or ax, ax jz short loc_close_dos_sf mov word ptr [u_count], ax mov word ptr [u_base], offset ReadBuffer mov ax, word ptr [u_dirbuf] call write_i jnc short loc_read_dos_sf jmp short loc_unix_fd_write_error loc_close_dos_sf: pushf mov ah, 3Eh ; Close File mov bx, word ptr [FileHandle] int 21h popf jc loc_drv_read_error loc_update_boot_sector_and_sb: ; 18/11/2012 call sync jc short loc_unix_fd_write_error loc_write_SF_ok: mov si, offset Msg_OK call UNIX_PRINTMSG mov si, offset UNIX_CRLF call UNIX_PRINTMSG loc_exit: int 20h int 19h loc_unix_fd_write_error: mov ah, 3Eh ; Close File mov bx, word ptr [FileHandle] int 21h mov si, offset msg_unix_drv_write_error call UNIX_PRINTMSG jmp short loc_exit proc_start endp UNIX_PRINTMSG proc near UNIX_PRINTMSG_LOOP: lodsb ; Load byte at DS:SI to AL and AL,AL jz short UNIX_PRINTMSG_OK mov AH,0Eh mov BX,07h int 10h ; BIOS Service func ( ah ) = 0Eh ; Write char as TTY ;AL-char BH-page BL-color jmp short UNIX_PRINTMSG_LOOP UNIX_PRINTMSG_OK: retn UNIX_PRINTMSG endp proc_rw_char proc near ; OUTPUT -> DS:SI = Entered String (ASCIIZ) mov si, offset StartupFile_Name mov bx,7 mov ah,3 int 10h mov Word Ptr [Cursor_Pos], dx read_next_char: xor ah,ah int 16h and al,al jz short loc_arrow cmp al,0E0h je short loc_arrow cmp al,08h jne short char_return loc_back: mov bl,7 mov ah,3 int 10h cmp dl,byte ptr [Cursor_Pos] ja short prev_column loc_beep: mov ah, 0Eh mov al, 7 int 10h jmp short read_next_char prev_column: dec dl set_cursor_pos: mov ah,02h int 10h mov bl, dl sub bl,byte ptr [Cursor_Pos] mov cx,1 mov ah,09h mov al,20h mov byte ptr [SI][BX],al loc_write_it: mov bl,7 int 10h mov dx,word ptr [Cursor_Pos] jmp short read_next_char loc_arrow: cmp AH,4Bh je short loc_back cmp AH,53h je short loc_back jmp short read_next_char char_return: mov bl,7 mov ah,3 int 10h mov ah,dl sub ah,byte ptr [Cursor_Pos] cmp al,20h jb short loc_escape cmp ah,63 ja short loc_beep ; cmp al, "z" ; ja short read_next_char ; cmp al, "a" ; jb short pass_capitalize ; and al, 0DFh pass_capitalize: mov bl, ah xor ah, ah mov word ptr [SI][BX],ax mov ah, 0Eh mov bl, 7 int 10h jmp short read_next_char pass_escape: cmp al,0Dh jne short read_next_char mov bl,7 int 10h mov al,0Ah int 10h retn loc_escape: cmp al,1Bh jne short pass_escape stc retn proc_rw_char endp name_i proc near ; 11/11/2012 unixboot.asm ; Unix boot file configuration version ; 20/10/2012 ; 14/10/2012 ; Boot sector version of "namei" procedure ; Derived from (original) UNIX v1 source code ; PRELIMINARY release of Unix Implementation Document, ; 20/6/1972 ; ; RETRO UNIX v1 FS ; Boot sector version ; ; return i-number of file (ax) ; mov ax, ROOT_DIR_INODE_NUMBER ; 41 call i_get jc short name_inode_retn test word ptr [inode_flgs], 4000h ; directory i-node ? jnz short @f mov ah, 0FFh ; error number stc jmp short name_inode_retn @@: mov ax, word ptr [inode_size] ; 11/11/2012 Unix boot file configuration version mov word ptr [u_dirp], ax ; 11/11/2012 Unix boot file configuration version xor ax, ax mov word ptr [u_off], ax ; u_off is file offset used by user name_inode_1: mov word ptr [u_base], offset u_dirbuf ; u.dirbuff holds a file name copied from ; a directory mov word ptr [u_count], 10 mov ax, ROOT_DIR_INODE_NUMBER call read_i ; read 10 bytes of file with i-number ; i.e. read a directory entry jc short name_inode_4 mov cx, word ptr [u_nread] or cx, cx jna short name_inode_3 ; gives error return ; 11/11/2012 ; Unix boot file configuration version ;;; mov bx, word ptr [u_dirbuf] and bx, bx ; Check i-number of directory entry jnz short name_inode_2 ; >0 means an active directory entry mov ax, word ptr [u_off] sub ax, 10 mov word ptr [u_dirp], ax jmp short name_inode_1 ;;; name_inode_2: mov si, offset BOOT_FILE_NAME ; mov di, offset u_dirbuf + 2 ; points to file name of directory entry mov dx, offset u_dirbuf + 10 @@: lodsb ; mov al, byte ptr [SI], inc si scasb ; compare char in boot file name to file name char ; read from directory; brach if chars match jne short short name_inode_1 ; File names do not match, go to next directory entry or al, al jz short name_inode_retn ; If char is nul, then the last char in string has ; been compared cmp di, dx ; have i checked all 8 bytes of file name jna short @b ; name_inode_retn: mov ax, word ptr [u_dirbuf] ; 20/10/2012, ax = i-number of the boot file retn ;jmp short name_inode_retn ; File names match name_inode_3: mov ah, 0FFh ; Error code stc name_inode_4: retn name_i endp read_i proc near ; 01/03/2013 ; 14/10/2012 ; Boot sector version of "readi" procedure ; Derived from (original) UNIX v1 source code ; PRELIMINARY release of Unix Implementation Document, ; 20/6/1972 ;;AX (R1) = i-number ; RETRO UNIX v1 FS ; Boot sector version ; ; read from an i-node ; xor dx, dx ; 0 mov word ptr [u_nread], dx ; accumulated number of bytes transmitted cmp word ptr [u_count], dx ; is number of byte to read greater than 0 jna short read_inode_retn read_inode_1: ; AX = I-Number push ax call i_get ; get i-node into i-node section of core jc short read_inode_3 ; 01/03/2013 mov dx, word ptr [inode_size] ; file size in bytes in r2 (DX) sub dx, word ptr [u_off] ; subtract file offset jna short read_inode_3 cmp dx, word ptr [u_count] ; are enough bytes left in file to carry out read jnb short read_inode_2 mov word ptr [u_count], dx read_inode_2: call m_get ; returns physical block number of block in file ; where offset points jc short read_inode_3 ; 01/03/2013 ; AX = Physical block number call dsk_rd ; read in block, BX points to 1st word of data in ; buffer jc short read_inode_3 readinode_sioreg: mov si, word ptr [u_off] ; R2 mov cx, si ; cx = R3, si = R2 or cx, 0FE00h ; set bits 9...15 of file offset in R3 and si, 1FFh ; calculate file offset mod 512 add si, bx ; offset WriteBuffer ; si now points to 1st byte in buffer ; where data is to be placed mov di, word ptr [u_base] ; R1 neg cx ; 512 - file offset(mod512) in R3 (cx) cmp cx, word ptr [u_count] jna short @f ; 2f mov cx, word ptr [u_count] @@: add word ptr [u_nread], cx ; r3 + number of bytes ; xmitted during write is put into ; u_nread sub word ptr [u_count], cx add word ptr [u_base], cx ; points to 1st of remaining ; data bytes add word ptr [u_off], cx ; new file offset = number ; of bytes done + old file offset ; end of readinode_sioreg ; DI = file (user data) offset ; SI = sector (I/O) buffer offset ; CX = byte count rep movsb pop ax cmp word ptr [u_count], 0 ja short read_inode_1 retn read_inode_3: pop ax ; i-number read_inode_retn: retn read_i endp i_get proc near ; 18/11/2012 unix boot file configuration version ; of "iget" procedure. ; 16/9/2012 ; 14/7/2012 ; Derived from (original) UNIX v1 source code ; PRELIMINARY release of Unix Implementation Document, ; 20/6/1972 ;; AX=R1 ; RETRO UNIX v1 FS ;; return => if cf=1 error number in [Error] cmp ax, word ptr [ii] ; AX (R1) = i-number of current file je short iget_4 iget_1: mov dl, byte ptr [imod] and dl, dl ; has i-node of current file been modified ? jz short iget_2 xor dl, dl ; mov al, 0 mov byte ptr [imod], dl push ax mov ax, word ptr [ii] inc dl ; mov dl, 1 ; dl = 1 = write call i_calc pop dx jc short iget_4 mov ax, dx iget_2: and ax, ax jz short iget_3 mov word ptr [ii], ax xor dl, dl ; dl = 0 = read call i_calc iget_3: mov ax, word ptr [ii] iget_4: retn i_get endp i_calc proc near ; 18/11/2012 unix boot file configuration version ; of "icalc" procedure. ; 17/8/2012 ; 14/7/2012 ; Derived from (original) UNIX v1 source code ; PRELIMINARY release of Unix Implementation Document, ; 20/6/1972 ;; AX=R1 ; 0 = read, 1 = write ; RETRO UNIX v1 FS ; ; i-node is located in block (i+47)/16 and ; begins 32*(i+47) mod 16 bytes from its start ;; return => if cf=1 error number in [Error] ; input -> dl = 0 -> read, 1 = Write mov byte ptr [rw], dl add ax, 47 ; add 47 to inode number push ax ; R1 -> -(SP) shr ax, 1 ; divide by 16 shr ax, 1 shr ax, 1 shr ax, 1 ; ax contains block number of block in which ; inode exists call dsk_rd pop dx jc short icalc_4 icalc_1: and dx, 0Fh ; (i+47) mod 16 shl dx, 1 shl dx, 1 shl dx, 1 shl dx, 1 shl dx, 1 ; DX = 32 * ((i+47) mod 16) ; DX (R5) points to first word in i-node i. mov di, offset inode ; inode is address of first word of current inode mov cx, 16 ; CX = R3 mov si, offset WriteBuffer add si, dx cmp byte ptr [rw], 0 jna short icalc_3 ; 0 = read (and copy i-node to memory) icalc_2: xchg si, di ; over write old i-node (in buffer to be written) rep movsw mov ax, word ptr [buff_s] ; 18/11/2012 call dsk_wr retn icalc_3: ; copy new i-node into inode area of (core) memory rep movsw icalc_4: retn i_calc endp dsk_rd proc near ; 28/11/2012 BugFix ; 20/10/2012 (buff_s) ; 14/10/2012 ; fd boot sector version of "dskrd" procedure ; Derived from (original) UNIX v1 source code ; PRELIMINARY release of Unix Implementation Document, ; 20/6/1972 ; RETRO UNIX v1 FS ; floppy disk boot sector version ;; return => if cf=1 error number in [Error] ; ax = sector/block number mov bx, offset WriteBuffer ; 28/11/2012 cmp ax, word ptr [buff_s] ; buffer sector je short dsk_rd_3 mov si, ax xor ch, ch mov cl, 4 ; Retry count dsk_rd_1: push cx mov dx, 18 ; Sectors per track div dl mov cl, ah ; Sector (zero based) inc cl ; To make it 1 based shr al, 1 ; Convert Track to Cylinder adc dh, 0 ; Heads (0 or 1) mov dl, byte ptr [PhysicalDriveNumber] mov ch, al mov ah, 2 ; 2=read mov al, 01h int 13h ; BIOS Service func ( ah ) = 2 ; Read disk sectors ; BIOS Service func ( ah ) = 3 ; Write disk sectors ;AL-sec num CH-cyl CL-sec ; DH-head DL-drive ES:BX-buffer ;CF-flag AH-stat AL-sec read pop cx jnc short dsk_rd_2 loop dsk_rd_1 dsk_rd_2: mov word ptr [buff_s], si dsk_rd_3: retn dsk_rd endp m_get proc near ; 01/03/2013 ; 18/11/2012 ; 14/11/2012 unix boot file configuration version ; of "mget" procedure ; 31/10/2012 ; 20/10/2012 ; 19/8/2012 ; 13/8/2012 ; 27/7/2012 ; 21/7/2012 ; Derived from (original) UNIX v1 source code ; PRELIMINARY release of Unix Implementation Document, ; 20/6/1972 ;; return -> AX=R1 ; RETRO UNIX v1 FS ; initialization/format version ; cf -> 1 = error (no free block) ;push bx ;push cx ;push dx ;; contents of bx, cx, dx will be destroyed mget_0: mov bl, byte ptr [u_off]+1 xor bh, bh ; BX = R2 test word ptr [inode_flgs], 4096 ; 1000h ; is this a large or small file jnz short mget_5 ; 4f ; large file test bl, 0F0h ; !0Fh ; error if BX (R2) >= 16 jnz short mget_2 and bl, 0Eh ; clear all bits but bits 1,2,3 mov ax, word ptr inode_dskp[BX] ; AX = R1, physical block number or ax, ax jnz short mget_1 ; if physical block number is zero ; then need a new block for file call sb_alloc ; allocate a new block for this file ; AX (R1) = Block number jc short mget_8 ; ; cf -> 1 & ax = 0 -> no free block mov word ptr inode_dskp[BX], ax call set_imod call b_clear mget_1: ; 2 ; AX (R1) = Physical block number ;pop dx ;pop cx ;pop bx retn mget_2: ; 3 ; adding on block which changes small file to large file call sb_alloc ; call wslot ; setup I/O buffer for write ; ; R5 points to the first data word in buffer ; push ds ; pop es mov word ptr [buff_s], ax ; Block/Sector number ;push si ;push di push ax mov cx, 8 ; R3, transfer old physical block pointers ; into new indirect block area for the new ; large file mov di, offset WriteBuffer ; BX = R5 mov si, offset inode_dskp xor ax, ax ; mov ax, 0 mget_3: ; 1 movsw mov word ptr [SI]-2, ax loop mget_3 mov cl, 256-8 ; clear rest of data buffer mget_4: ; 1 rep stosw pop ax ;pop di ;pop si ;mov byte ptr [buff_m], 1 ; modified call dsk_wr ;jc short mget_1 jc short mget_8 ; 01/03/2013 mov ax, word ptr [buff_s] mov word ptr [inode_dskp], ax or word ptr [inode_flgs], 4096 ; 1000h call set_imod jmp short mget_0 mget_9: pop ax mget_8: ;mov ax, err_NOFREEBLOCK ;pop dx ;pop cx ;pop bx retn mget_5: ; 4 ; large file ; 05/03/2013 ;mov ax, bx ; bx <= 255 for this file (UNIX v1, RUFS) system ;mov cx, 256 ; 01/03/2013 no need a division here ;xor dx, dx ; 01/03/2013 no need a division here ;div cx ; 01/03/2013 no need a division here ;and bx, 1FEh ; zero all bit but 1,2,3,4,5,6,7,8 ; gives offset in indirect block ;push bx ; R2 ;mov bx, ax ; calculate offset in i-node for pointer ; to proper indirect block ;and bx, 0Eh ;mov ax, word ptr inode_dskp[BX] ; R1 and bl, 0FEh ; ah = 0 ; 01/03/2013 push bx ; i-node pointer offset in indirect block ; 01/03/2013 Max. possible BX (offset) value is 127 (65535/512) ; for this file system (offset 128 to 255 not in use) ; There is always 1 indirect block for this file system mov ax, word ptr [inode_dskp] ; inode_dskp[0] or ax, ax ; R1 jnz short mget_6 ; 2f call sb_alloc jc short mget_9 ; 01/03/2013 mov word ptr inode_dskp[BX], ax ; R1, block number call set_imod call b_clear mget_6: ;2 ; ax = R1, block number call dsk_rd ; read indirect block pop bx ; R2, get offset jc short mget_7 add bx, offset WriteBuffer ; R5, first word of indirect block mov ax, word ptr [bx] ; put physical block no of block ; in file sought in R1 (AX) or ax, ax jnz short mget_7 ; 2f call sb_alloc jc short mget_8 ; 01/03/2013 mov word ptr [bx], ax ; R1 push ax mov ax, word ptr [buff_s] ;mov byte ptr [buff_m], 1 ; modified ;call wslot call dsk_wr pop dx ; 18/11/2012 jc short mget_7 mov ax, dx ; 18/11/2012 ; ax = R1, block number of new block call b_clear mget_7: ; 2 ; ax = R1, block number of new block ;pop dx ;pop cx ;pop bx retn m_get endp sb_alloc proc near ; 14/11/2012 unix boot file configuration version ; of "alloc" procedure ; 21/8/2012 ; 18/8/2012 ; 17/8/2012 ; 5/8/2012 ; 21/7/2012 ; Derived from (original) UNIX v1 source code ; PRELIMINARY release of Unix Implementation Document, ; 20/6/1972 ;; input -> AX=R1 ;; output -> AX=R1 ; RETRO UNIX v1 FS ;push cx push bx ; R2 ;push dx ; R3 mov bx, offset systm ; SuperBlock ; start of inode and free storage map for disk alloc_1: ; 1 mov ax, word ptr [BX] ; first word contains # of bytes ; in free storage map shl ax, 1 ; multiply AX (R1) by 8 gives # of blocks shl ax, 1 shl ax, 1 mov cx, ax ; R1, bit count of free storage map xor ax, ax ; 0 alloc_2: ; 1 inc bx ; 18/8/2012 inc bx ; mov dx, word ptr [BX] ; mov (R2)+, R3 or dx, dx jnz short alloc_3 ; 1f ; branch if any free blocks in this word add ax, 16 cmp ax, cx jb short alloc_2 ; 1b ;jmp short panic ; no free storage xor ax, ax stc ; cf=1 --> error: no free block jmp short alloc_7 alloc_3: ; 1 shr dx, 1 ; R3 ; Branch when free block found, ; bit for block k is in byte k/8 ; in bit k (mod 8) jc short alloc_4 ; 1f inc ax ; R1 ; increment bit count in bit k (mod 8) jmp short alloc_3 ; 1b alloc_4: ;call free_3 sb_alloc_free_3: mov dx, 1 mov cx, ax and cx, 0Fh jz short @f shl dx, cl @@: mov bx, ax shr bx, 1 shr bx, 1 shr bx, 1 shr bx, 1 free_4: ; 1 shl bx, 1 ; 21/8/2012 ; BX (R2) = k/8 add bx, offset systm+2 ; SuperBlock+2 alloc_5: ; 1 ; 21/8/2012 not dx ; masking bit is '0' and others are '1' and word ptr [BX], dx ; bic r3, (r2) ; 0 -> allocated retn alloc_6: ; inc byte ptr [smod] ; super block modified sign ;mov byte ptr [smod], 1 alloc_7: ;pop dx ; R3 pop bx ; R2 ;pop cx ; AX (R1) = Block number retn sb_alloc endp set_imod proc near ; 14/11/2012 unix boot file configuration version ; of "setimod" procedure ; 13/8/2012 ; 21/7/2012 ; 14/7/2012 ; Derived from (original) UNIX v1 source code ; PRELIMINARY release of Unix Implementation Document, ; 20/6/1972 ;; AX=R0, BX=R1, CX=R3, DX=R5 ; [SP] = Argument 1, 0 = read, 1 = write ; RETRO UNIX v1 FS ; initialization/format version ; ;push dx push ax mov byte ptr [imod], 1 ; Erdogan Tan 14-7-2012 call epoch mov word ptr [inode_mtim], ax mov word ptr [inode_mtim]+2, dx cmp word ptr [inode_ctim], 0 ja short @f cmp word ptr [inode_ctim]+2, 0 ja short @f mov word ptr [inode_ctim], ax mov word ptr [inode_ctim]+2, dx @@: pop ax ;pop dx retn set_imod endp b_clear proc near ; 18/11/2012 ; 14/11/2012 unix boot file configuration version ; of "clear" procedure ; 5/8/2012 ; 21/7/2012 ; Derived from (original) UNIX v1 source code ; PRELIMINARY release of Unix Implementation Document, ; 20/6/1972 ;; input -> AX=R1 (block number) ;; output -> AX=R1 ; RETRO UNIX v1 FS ; initialization/format version ;call wslot ; setup I/O buffer for write ; ; R5 points to the first data word in buffer ; BX = R5 mov word ptr [buff_s], ax ;push ds ;pop es ;push di ;push cx push ax xor ax, ax ; mov di, bx mov di, offset WriteBuffer mov cx, 256 rep stosw ;mov byte ptr [buff_m], 1 ; modified mov ax, word ptr [buff_s] ; 18/11/2012 call dsk_wr pop ax ;pop cx ;pop di retn b_clear endp mak_nod proc near ; 01/03/2013 ; 02/12/2012 (maknod_imap -> call imap) ; 25/11/2012 ; 18/11/2012 ; 11/11/2012 ; unixboot.asm (boot file configuration) ; version of 'maknod' ; ; 30/10/2012 ; AX = R1, mode ; Derived from (original) UNIX v1 source code ; PRELIMINARY release of Unix Implementation Document, ; 20/6/1972 ; RETRO UNIX v1 FS ; ; maknod : create an i-node and make a directory entry ; ; 8086 CPU & IBM PC architecture modifications by Erdogan Tan ; ; return => if cf=1 error code in AH ; If cf=0 -> AX = I-Number (also in u.dirbuff) or ah, 80h ; 10000000b, allocate flag set push ax ; put mode on stack ;mov ax, word ptr [ii] ; move current i-number to BX/r1 ;mov ax, ROOT_DIR_INODE_NUMBER ; 41 ;call i_get ;jc short short maknod_2 ;test word ptr [i.flags], 4000h ; directory i-node ? ;jnz short maknod_1 ;mov ah, 0FFh ; error number ;stc ;jmp short maknod_2 mov ax, 41 ; r1 = 41 maknod_1: ; 1 ; scan for a free i-node inc ax ; r1 = r1 + 1 ; 2/12/2012 call imap ; get byte address and bit position in inode map in ; r2 (DX) & mq (BX) ; DX (MQ) has a 1 in the calculated bit position ; BX (R2) has byte address of the byte with allocation bit test byte ptr [BX], dl ; bitb mq,(r2) / is the i-node active jnz short maknod_1 ; bne 1b / yes, try the next one or byte ptr [BX], dl ; bisb mq,(r2) ; no, make it active (put a 1 in the bit map) ; ax = i-number call i_get ; jsr r0,iget / get i-node into core jc short maknod_2 test word ptr [inode_flgs], 8000h ; is i-node already allocated jnz short maknod_1 ; 1b / yes, look for another one mov word ptr [u_dirbuf], ax ; mov r1, u.dirbuf ; no, put i-number in u.dirbuf mov ax, ROOT_DIR_INODE_NUMBER ; 41 call i_get ; jsr r0,iget / get i-node in core jc short maknod_2 call mk_dir ; jsr r0,mkdir ; make a directory entry in current directory jc short maknod_2 ; 01/03/2013 mov ax, word ptr [u_dirbuf] ; mov u.dirbuf,r1 ; ax / r1 = new inode number call i_get jc short maknod_2 ; jsr r0,copyz; inode; inode+32. / 0 it out mov cx, 16 xor ax, ax ; 0 mov di, offset inode rep stosw pop word ptr [inode_flgs] ; mov (sp)+,i.flgs / fill flags mov al, byte ptr [u_uid] ; movb u.uid,i.uid / user id mov byte ptr [inode_uid], al mov byte ptr [inode_nlks], 1 ; movb $1,i.nlks / 1 link ;call epoch ;mov word ptr [s_time], ax ;mov word ptr [s_time]+2, dx ;mov word ptr [inode_ctim], ax ; mov s.time,i.ctim / time created ;mov word ptr [inode_ctim]+2, dx ; mov s.time+2,i.ctim+2 ; 25/11/2012 mov ax, word ptr [bf_make_datetime] mov dx, word ptr [bf_make_datetime]+2 mov word ptr [inode_ctim], ax mov word ptr [inode_ctim]+2, dx call set_imod mov ax, word ptr [u_dirbuf] retn maknod_2: pop ax retn mak_nod endp mk_dir proc near ; 11/11/2012 ; unixboot.asm (boot file configuration) ; version of 'mkdir' ; ; 31/10/2012 ; Derived from (original) UNIX v1 source code ; PRELIMINARY release of Unix Implementation Document, ; 20/6/1972 ; RETRO UNIX v1 FS ; ; mkdir : make a directory entry ; ; 8086 CPU & IBM PC architecture modifications by Erdogan Tan ; ; return => if cf=1 error number in [Error], ax = mode ; If cf=0 -> AX = I-Number (also in u.dirbuff) ; ; input: ; u.namep = file name ; ii = current directory's i-number ; u.dirbuf = directory entry (source) location ; output: ; u.dirbuf+2 to u.dirbuf+10 = file name ; u.off = directory entry offset in current directory ; u.base = start of u.dirbuf ; ;;;r1 (AX) = i-number of current directory mkdir_0: ; jsr r0,copyz; u.dirbuf+2; u.dirbuf+10. / clear this mov cx, 4 xor ax, ax mov di, offset u_dirbuf+2 rep stosw mov si, word ptr [u_namep] ; mov u.namep,r2 ; r2 points to name of directory entry mov di, offset u_dirbuf+2 ; mov $u.dirbuf+2,r3 ; r3 points to u.dirbuf+2 mkdir_1: ;1 / put characters in the directory name in u.dirbuf+2 - u.dirbuf+10 lodsb ;movb (r2)+,r1 / move character in name to r1 and al, al jz short mkdir_2 ; beq 1f / if null, done cmp al, '/' ; cmp r1,$'/ / is it a "/"? je short mkdir_stc ; beq error9 / yes, error cmp di, offset u_dirbuf+10 ; cmp r3,$u.dirbuf+10. ; have we reached the last slot for ; a char? je short mkdir_1 ; beq 1b / yes, go back stosb ; movb r1,(r3)+ ; no, put the char in the u.dirbuf jmp short mkdir_1 ; br 1b / get next char mkdir_2: ;1 mov ax, word ptr [u_dirp] ; mov u.dirp,u.off mov word ptr [u_off], ax ; pointer to empty current directory ; slot to u.off wdir: mov word ptr [u_base], offset u_dirbuf ; mov$u.dirbuf,u.base ; u.base points to created file name mov word ptr [u_count], 10 ; mov $10.,u.count ; u.count = 10 mov ax, word ptr [ii] ; mov ii,r1 ; r1 has i-number of current directory call write_i ; jsr r0,writei / write into directory @@: retn ; rts r0 mkdir_stc: ; invalid file name, al="/", ah=0 mov ah, 1 stc retn mk_dir endp write_i proc near ; 18/11/2012 ; 11/11/2012 ; unixboot.asm (boot file configuration) ; version of 'writei' ; ; 31/10/2012 ; 18/08/2012 ; 17/07/2012 ; BX = R1, i-number ; Derived from (original) UNIX v1 source code ; PRELIMINARY release of Unix Implementation Document, ; 20/6/1972 ; ; RETRO UNIX v1 FS ; initialization/format version ; ; writei: write file ; ; 8086 CPU & IBM PC architecture modifications by Erdogan Tan ;; return => if cf=1 error number in [Error] ; input: ; AX = R1 = I-Number ; u.count = byte count ; u.base = user buffer (offset) ; u.fofp = (pointer to) current file offset xor dx, dx ; 0 ; clr u.nread mov word ptr [u_nread], dx ; clear the number of bytes transmitted during ; read or write calls ; tst u.count cmp word ptr [u_count], dx ; test the byte count specified by the user ;ja short write_1 ; 1f ; bgt 1f / any bytes to output; yes, branch ;retn ; rts 0 / no, return - no writing to do jna short write_inode_retn write_1: ;push ax ; save i-number on stack call i_get ; jsr r0,iget ; write i-node out (if modified), read i-node 'r1' ; into i-node area of core mov dx, word ptr [u_off] add dx, word ptr [u_count] ; add u.count,r2 ; no. of bytes to be written + file offset is ; put in r2 cmp dx, word ptr [inode_size] ; cmp r2,i.size ; is this greater than the present size of ; the file? jna short dskw_1 ; blos 1f / no, branch mov word ptr [inode_size], dx ; mov r2,i.size ; yes, increase the file size to file offset + ; no. of data bytes call set_imod ; jsr r0,setimod ; set imod=1 (i.e., core inode has been ; modified), stuff time of modification into ; core image of i-node dskw_1: ; 1 call m_get ; jsr r0,mget ; get the block no. in which to write the next data ; byte ; AX = R1 = Block Number mov bx, word ptr [u_off] and bx, 1FFh ; bit *u.fofp,$777 ; test the lower 9 bits of the file offset jnz short dskw_2 ; bne 2f ; if its non-zero, branch; if zero, file offset = 0, ; 512, 1024,...(i.e., start of new block) cmp word ptr [u_count], 512 ; cmp u.count,$512. ; if zero, is there enough data to fill an ; entire block? (i.e., no. of ;jnb short dskw_3 ; bhis 3f / bytes to be written greater than 512.? ; Yes, branch. / Don't have to read block ; 18/11/2012 jb short dskw_2 mov word ptr [buff_s], ax jmp short short dskw_3 dskw_2: ; 2 ; in as no past info. is to be saved (the entire block will be ; overwritten). ; AX=R1 (block number) call dsk_rd ; jsr r0,dskrd ; no, must retain old info.. Hence, read block 'r1' ; into an I/O buffer ; 11/11/2012 jc short dskw_5 mov ax,word ptr [buff_s] dskw_3: ; 3 ;call wslot writeinode_sioreg: ; call sioreg mov di, word ptr [u_off] ; R2 mov cx, di ; cx = R3, di = R2 or cx, 0FE00h ; set bits 9...15 of file offset in R3 and di, 1FFh ; calculate file offset mod 512 add di, offset WriteBuffer ; di now points to 1st byte in buffer ; where data is to be placed mov si, word ptr [u_base] ; R1 neg cx ; 512 - file offset(mod512) in R3 (cx) cmp cx, word ptr [u_count] jna short @f ; 2f mov cx, word ptr [u_count] @@: add word ptr [u_nread], cx ; r3 + number of bytes ; xmitted during write is put into ; u_nread sub word ptr [u_count], cx add word ptr [u_base], cx ; points to 1st of remaining ; data bytes add word ptr [u_off], cx ; new file offset = number ; of bytes done + old file offset ; end of writeinode_sioreg ; SI = user data offset (r1) ; DI = sector (I/O) buffer offset (r2) ; CX = byte count (r3) dskw_4: ; 2 rep movsb ; ax = block/sector number call dsk_wr ; jsr r0,dskwr / write the block and the i-node jc short dskw_5 cmp word ptr [u_count], 0 ; any more data to write? ja short dskw_1 ; 1b ; yes, branch dskw_5: ; pop ax ; i-number write_inode_retn: retn write_i endp dsk_wr proc near ; 11/11/2012 ; unix boot file configuration version of "dskwr" procedure ; ; Derived from (original) UNIX v1 source code ; PRELIMINARY release of Unix Implementation Document, ; 20/6/1972 ; RETRO UNIX v1 FS ;; return => if cf=1 error number in [Error] ; ax = sector/block number mov bx, offset WriteBuffer xor ch, ch mov cl, 4 ; Retry count dsk_wr_1: push cx mov dx, 18 ; Sectors per track div dl mov cl, ah ; Sector (zero based) inc cl ; To make it 1 based shr al, 1 ; Convert Track to Cylinder adc dh, 0 ; Heads (0 or 1) mov dl, byte ptr [PhysicalDriveNumber] mov ch, al mov ah, 3 ; 3=write mov al, 01h int 13h ; BIOS Service func ( ah ) = 2 ; Read disk sectors ; BIOS Service func ( ah ) = 3 ; Write disk sectors ;AL-sec num CH-cyl CL-sec ; DH-head DL-drive ES:BX-buffer ;CF-flag AH-stat AL-sec read pop cx jnc short dsk_wr_2 loop dsk_wr_1 dsk_wr_2: retn dsk_wr endp epoch proc near ; 14/11/2012 ; unixboot.asm (boot file configuration) ; version of "epoch" procedure in "unixproc.asm" ; 21/7/2012 ; 15/7/2012 ; 14/7/2012 ; Erdogan Tan - RETRO UNIX v0.1 ; compute current date and time as UNIX Epoch/Time ; UNIX Epoch: seconds since 1/1/1970 00:00:00 ; 21/7/2012 ;push bx ;push cx mov ah, 02h ; Return Current Time int 1Ah xchg ch,cl mov word ptr [hour], cx xchg dh,dl mov word ptr [second], dx mov ah, 04h ; Return Current Date int 1Ah xchg ch,cl mov word ptr [year], cx xchg dh,dl mov word ptr [month], dx mov cx, 3030h mov al, byte ptr [hour] ; Hour ; AL <= BCD number) db 0D4h,10h ; Undocumented inst. AAM ; AH = AL / 10h ; AL = AL MOD 10h aad ; AX= AH*10+AL mov byte ptr [hour], al mov al, byte ptr [hour]+1 ; Minute ; AL <= BCD number) db 0D4h,10h ; Undocumented inst. AAM ; AH = AL / 10h ; AL = AL MOD 10h aad ; AX= AH*10+AL mov byte ptr [minute], al mov al, byte ptr [second] ; Second ; AL <= BCD number) db 0D4h,10h ; Undocumented inst. AAM ; AH = AL / 10h ; AL = AL MOD 10h aad ; AX= AH*10+AL mov byte ptr [second], al mov ax, word ptr [year] ; Year (century) push ax ; AL <= BCD number) db 0D4h,10h ; Undocumented inst. AAM ; AH = AL / 10h ; AL = AL MOD 10h aad ; AX= AH*10+AL mov ah, 100 mul ah mov word ptr [year], ax pop ax mov al, ah ; AL <= BCD number) db 0D4h,10h ; Undocumented inst. AAM ; AH = AL / 10h ; AL = AL MOD 10h aad ; AX= AH*10+AL add word ptr [year], ax mov al, byte ptr [month] ; Month ; AL <= BCD number) db 0D4h,10h ; Undocumented inst. AAM ; AH = AL / 10h ; AL = AL MOD 10h aad ; AX= AH*10+AL mov byte ptr [month], al mov al, byte ptr [month]+1 ; Day ; AL <= BCD number) db 0D4h,10h ; Undocumented inst. AAM ; AH = AL / 10h ; AL = AL MOD 10h aad ; AX= AH*10+AL mov byte ptr [Day], al convert_to_epoch: ; Derived from DALLAS Semiconductor ; Application Note 31 (DS1602/DS1603) ; 6 May 1998 mov dx, word ptr [year] sub dx, 1970 mov ax, 365 mul dx xor bh, bh mov bl, byte ptr [month] dec bl shl bl, 1 mov cx, word ptr DMonth[BX] mov bl, byte ptr [Day] dec bl add ax, cx adc dx, 0 add ax, bx adc dx, 0 ; DX:AX = days since 1/1/1970 mov cx, word ptr [year] sub cx, 1969 shr cx, 1 shr cx, 1 ; (year-1969)/4 add ax, cx adc dx, 0 ; + leap days since 1/1/1970 cmp byte ptr [month], 2 ; if past february jna short @f mov cx, word ptr [year] and cx, 3 ; year mod 4 jnz short @f ; and if leap year add ax, 1 ; add this year's leap day (february 29) adc dx, 0 @@: ; compute seconds since 1/1/1970 mov bx, 24 call proc_mul32 mov bl, byte ptr [hour] add ax, bx adc dx, 0 mov bx, 60 call proc_mul32 mov bl, byte ptr [minute] add ax, bx adc dx, 0 mov bx, 60 call proc_mul32 mov bl, byte ptr [second] add ax, bx adc dx, 0 ; DX:AX -> seconds since 1/1/1970 00:00:00 ; 21/7/2012 ;pop cx ;pop bx retn epoch endp convert_from_epoch proc near ; 30/11/2012 ; Derived from DALLAS Semiconductor ; Application Note 31 (DS1602/DS1603) ; 6 May 1998 ; ; INPUT: ; DX:AX = Unix (Epoch) Time mov cx, 60 call proc_div32 ;mov word ptr [imin], ax ; whole minutes ;mov word ptr [imin]+2, dx ; since 1/1/1970 mov word ptr [second], bx ; leftover seconds ; mov cx, 60 call proc_div32 ;mov word ptr [ihrs], ax ; whole hours ;mov word ptr [ihrs]+2, dx ; since 1/1/1970 mov word ptr [minute], bx ; leftover minutes ; mov cx, 24 mov cl, 24 call proc_div32 ;mov word ptr [iday], ax ; whole hours ; since 1/1/1970 ; mov word ptr [iday]+2, dx ; DX = 0 mov word ptr [hour], bx ; leftover hours add ax, 365+366 ; whole day since ; 1/1/1968 ; adc dx, 0 ; DX = 0 ; mov word ptr [iday], ax push ax mov cx, (4*365)+1 ; 4 years = 1461 days call proc_div32 pop cx ;mov word ptr [lday], ax ; count of quadyrs (4 years) push bx ;mov word ptr [qday], bx ; days since quadyr began cmp bx, 31 + 29 ; if past feb 29 then cmc ; add this quadyr's leap day adc ax, 0 ; to # of qadyrs (leap days) ;mov word ptr [lday], ax ; since 1968 ;mov cx, word ptr [iday] xchg cx, ax ; CX = lday, AX = iday sub ax, cx ; iday - lday mov cx, 365 ;xor dx, dx ; DX = 0 ; AX = iday-lday, DX = 0 call proc_div32 ;mov word ptr [iyrs], ax ; whole years since 1968 ; jday = iday - (iyrs*365) - lday ;mov word ptr [jday], bx ; days since 1/1 of current year add ax, 1968 ; compute year mov word ptr [year], ax mov dx, ax ;mov ax, word ptr [qday] pop ax cmp ax, 365 ; if qday <= 365 and qday >= 60 ja short @f ; jday = jday +1 cmp ax, 60 ; if past 2/29 and leap year then cmc ; add a leap day to the # of whole adc bx, 0 ; days since 1/1 of current year @@: ;mov word ptr [jday], bx mov cx, 12 ; estimate month xchg cx, bx ; CX = jday, BX = month mov ax, 366 ; mday, max. days since 1/1 is 365 and dx, 11b ; year mod 4 (and dx, 3) @@: ; Month calculation ; 0 to 11 (11 to 0) cmp cx, ax ; mday = # of days passed from 1/1 jnb short @f dec bx ; month = month - 1 shl bx, 1 mov ax, word ptr DMonth[BX] ; # elapsed days at 1st of month shr bx, 1 ; bx = month - 1 (0 to 11) cmp bx, 1 ; if month > 2 and year mod 4 = 0 jna short @b ; then mday = mday + 1 or dl, dl ; if past 2/29 and leap year then jnz short @b ; add leap day (to mday) inc ax ; mday = mday + 1 jmp short @b @@: inc bx ; -> bx = month, 1 to 12 mov word ptr [month], bx sub cx, ax ; day = jday - mday + 1 inc cx mov word ptr [day], cx ; ax, bx, cx, dx is changed at return ; output -> ; [year], [month], [day], [hour], [minute], [second] ; retn convert_from_epoch endp proc_mul32 proc near ; push cx mov cx, bx mov bx, dx mul cx xchg ax, bx push dx mul cx pop cx add ax, cx adc dx, 0 xchg bx, ax xchg dx, bx ; pop cx retn proc_mul32 endp proc_div32 proc near ; 1999 ; (Rx_Dos_Div32) 32 bit divide procedure ; by Erdogan Tan ; Input -> DX_AX = 32 bit dividend ; CX = 16 bit divisor ; output -> DX_AX = 32 bit quotient ; BX = 16 bit remainder mov bx, dx xchg ax, bx xor dx, dx div cx ; at first, divide DX xchg ax, bx ; remainder is in DX ; now, BX has quotient ; save remainder div cx ; so, DX_AX divided and ; AX has quotient ; DX has remainder xchg dx, bx ; finally, BX has remainder retn proc_div32 endp sync proc near ; 18/11/2012 unix boot file configuration version ; of "sync" procedure of retro unix v1.0 by Erdogan Tan ; 12/8/2012 ; updates super block and the last i-node on disk ; if modified ; e.g. smod = 1, imod = 1, buffer_m = 1 ; ; RETRO UNIX v1 FS xor ax, ax ; mov ax, 0 call i_get ; (write modified i-node) jc short sync_2 sync_1: mov bx, offset BSBuffer mov ax,0302h ; Write boot sector & super block mov cx,1 xor dh,dh ;mov dl, byte ptr [PhysicalDriveNumber] int 13h sync_2: retn sync endp find_bfn proc near ; 26/11/2012 ; 25/11/2012 ; ; find boot file name by i-number (ax) ; ; cf -> 1 means error, ax = 0 -> not found mov word ptr [bf_i_number], ax push si mov ax, ROOT_DIR_INODE_NUMBER ; 41 call i_get jc short loc_find_bfn_retn ;test word ptr [inode_flgs], 4000h ; directory i-node ? ;jnz short @f ;mov ah, 0FFh ; error number ;stc ;jmp short loc_find_bfn_retn ;;@@: xor ax, ax mov word ptr [u_off], ax ; u_off is file offset used by user loc_find_bfn_1: mov word ptr [u_base], offset u_dirbuf ; u.dirbuff holds a file name copied from ; a directory mov word ptr [u_count], 10 mov ax, ROOT_DIR_INODE_NUMBER call read_i ; read 10 bytes of file with i-number ; i.e. read a directory entry jc short loc_find_bfn_retn mov ax, word ptr [u_nread] or ax, ax jz short loc_find_bfn_2 ; gives error return mov ax, word ptr [u_dirbuf] cmp ax, word ptr [bf_i_number] ; Check i-number of directory entry jne short loc_find_bfn_1 ; if same with specified bf_i_number ; it is the boot file loc_find_bfn_3: call i_get loc_find_bfn_retn: pop si retn loc_find_bfn_2: stc jmp short loc_find_bfn_retn find_bfn endp proc_display_startupfile_info proc near ; 30/11/2012 ; 29/11/2012 ; @@ ; 25/11/2012 mov si, offset Msg_StartupFile_Name call UNIX_PRINTMSG mov si, offset Boot_File_Name call UNIX_PRINTMSG mov si, offset Str_Inode_Number call UNIX_PRINTMSG mov si, offset BSBuffer mov ax, word ptr [SI]+bs_BF_inode_Number mov si, offset Decimal_i_no_str mov cx, 5 call proc_bin_to_decimal mov si, offset Decimal_i_no_str mov cx, 4 @@: cmp byte ptr [SI], '0' ja short @f inc si loop @b @@: call UNIX_PRINTMSG mov si, offset Str_startup_file_size call UNIX_PRINTMSG mov ax, word ptr [Inode_size] mov si, offset Decimal_size_str ;mov cx, 5 mov cl, 5 call proc_bin_to_decimal mov si, offset Decimal_size_str mov cl, 4 @@: cmp byte ptr [SI], '0' ja short @f inc si loop @b @@: call UNIX_PRINTMSG mov si, offset Str_Bytes call UNIX_PRINTMSG ; 30/11/2012 mov si, 3030h mov ax, word ptr [Inode_ctim] mov dx, word ptr [Inode_ctim]+2 call convert_from_epoch mov ax, word ptr [year] mov si, offset str_cyear ;mov cx, 4 mov cl, 4 call proc_bin_to_decimal mov ax, word ptr [month] mov si, offset str_cmonth mov cl, 2 call proc_bin_to_decimal mov ax, word ptr [day] mov si, offset str_cday mov cl, 2 call proc_bin_to_decimal mov ax, word ptr [hour] mov si, offset str_chour mov cl, 2 call proc_bin_to_decimal mov ax, word ptr [minute] mov si, offset str_cminute mov cl, 2 call proc_bin_to_decimal mov ax, word ptr [second] mov si, offset str_csecond mov cl, 2 call proc_bin_to_decimal mov ax, word ptr [Inode_mtim] mov dx, word ptr [Inode_mtim]+2 call convert_from_epoch mov ax, word ptr [year] mov si, offset str_myear ;mov cx, 4 mov cl, 4 call proc_bin_to_decimal mov ax, word ptr [month] mov si, offset str_mmonth mov cl, 2 call proc_bin_to_decimal mov ax, word ptr [day] mov si, offset str_mday mov cl, 2 call proc_bin_to_decimal mov ax, word ptr [hour] mov si, offset str_mhour mov cl, 2 call proc_bin_to_decimal mov ax, word ptr [minute] mov si, offset str_mminute mov cl, 2 call proc_bin_to_decimal mov ax, word ptr [second] mov si, offset str_msecond mov cl, 2 call proc_bin_to_decimal mov si, offset Str_SF_date_Time call UNIX_PRINTMSG retn proc_display_startupfile_info endp proc_bin_to_decimal proc near ; 30/11/2012 (CX input) ; 25/11/2012 unixboot.asm version ; 6-5-2009 ; Erdogan Tan ; INPUT: DS:SI = Target location ; AX = Binary Number ; CX = Number of digits ; OUTPUT: Decimal chars at DS:SI ; CX, AX, DX will be changed. ;push bp ;push si loc_reset_str_NumberInput: mov byte ptr [SI], "0" inc si loop loc_reset_str_NumberInput mov bp, sp xor dx, dx mov cx, 10 loc_rediv_NumberInput: div cx add dl,'0' push dx xor dx, dx dec si or ax, ax jnz short loc_rediv_NumberInput loop_popcx_NumberInput: pop dx mov byte ptr [SI], dl inc si cmp bp, sp jne short loop_popcx_NumberInput ;pop si ;pop bp retn proc_bin_to_decimal endp unlink proc near ; 02/12/2012 ; unix boot file configuration version ; of "sysunlink" function of retro unix v1.0 by Erdogan Tan ; Derived from (original) UNIX v1 source code ; PRELIMINARY release of Unix Implementation Document, ; 20/6/1972 ; ('sysunlink', unix kernel function) ; ; INPUT -> AX (R1) = inode number ; [u_off] = Directory Entry Offset + 10 ; [ii] = i-number of current directory ; Return -> CF = 0 -> Successed, CF = 1 -> failed ; (error code in AX) ;jsr r0,arg; u.namep / u.namep points to name ;jsr r0,namei / find the i-number associated ; with the path name ;br error9 / not found push ax ;mov r1,-(sp) / put its i-number on the stack ;jsr r0,isdir / is it a directory xor ax, ax mov word ptr [u_dirbuf], ax ; clr u.dirbuf / no, clear ;the location that will get written ;/ into the i-number portion of the entry sub word ptr [u_off], 10 ; sub $10.,u.off ; / move u.off back 1 directory entry ; not as unix original code ; because 'find_bfn' procedure loads boot file inode at return ; so, it is neded to reload root directory inode in core/memory mov ax, ROOT_DIR_INODE_NUMBER call i_get jnc short @f pop ax retn ; @@: call wdir ;jsr r0,wdir / free the directory entry pop ax ;mov (sp)+,r1 / get i-number back jc short @f call i_get ; jsr r0,iget / get i-node jc short @f call set_imod ; jsr r0,setimod / set modified flag dec byte ptr [inode_nlks] ; decb i.nlks ; / decrement the number of links jnz short @f ;bgt sysret9 ;/ if this was not the last link to file return call anyi ;jsr r0,anyi / if it was, see if anyone has it open. ;Then / free contents of file and destroy it. ;br sysret9 @@: retn unlink endp anyi proc near ; 02/12/2012 ; unix boot file configuration version ; of "anyi" procedure of retro unix v1.0 by Erdogan Tan ; Derived from (original) UNIX v1 source code ; PRELIMINARY release of Unix Implementation Document, ; 20/6/1972 ; ('anyi' procedure) ; ; INPUT -> AX (R1) = inode number ; Return -> CF = 0 -> Successed, CF = 1 -> failed ; ; mov $fsp,r2 / move start of fsp table to r2 anyi_1: ;1 ; cmp r1,(r2) / do i-numbers match? ; beq 1f / yes, 1f ; neg r1 / no complement r1 ; cmp r1,(r2) / do they match now? ; beq 1f / yes, transfer ; / i-numbers do not match ; add $8,r2 / no, bump to next entry in fsp table ; cmp r2,$fsp+[nfiles*8] / are we at last entry in the table ; blt 1b / no, check next entries i-number ; tst r1 / yes, no match ; bge .+4 ; neg r1 / make i-number positive call imap ; jsr r0,imap / get address of allocation bit ; in the i-map in r2 ; DX (MQ) has a 1 in the calculated bit position ; BX (R2) has byte address of the byte with allocation bit push bx ; retro unix modification (not as original unix code) push dx ; retro unix modification (not as original unix code) ; AX = i-number call itrunc ; jsr r0,itrunc / free all blocks related to i-node pop dx ; retro unix modification (not as original unix code) pop bx ; retro unix modification (not as original unix code) jc short @f ; (AX=0) ; retro unix modification-> 'call itrunc' moved up for ; keeping super block unmodified if itrunc return with an error not dx and byte ptr [BX], dl ; bicb mq,(r2) ; / clear bit for i-node in the imap ; xor ax, ax mov word ptr [inode_flgs], ax ; 0 ; clr i.flgs ; / clear all flags in the i-node @@: retn ; rts r0 / return ;anyi_2: ;1 / i-numbers match ; incb 7(r2) / increment upper byte of the 4th word ; rts r0 / in that fsp entry (deleted flag of fsp entry) anyi endp imap proc near ; 02/12/2012 ; unix boot file configuration version ; of "imap" procedure of retro unix v1.0 by Erdogan Tan ; Derived from (original) UNIX v1 source code ; PRELIMINARY release of Unix Implementation Document, ; 20/6/1972 ; ('imap' procedure) ; 11/11/2012 (maknod_imap location -> imap procedure) mov bx, ax ; BX = R2, AX = R1 (input, i-number) sub bx, 41 ; BX has i-41 mov cl, bl ; CX = R3 mov dx, 1 ; and cl, 7 ; CX has (i-41) mod 8 to get the bit position jz short @f ; 21/8/2012 shl dx, cl ; DX has 1 in the calculated bit position @@: shr bx, 1 shr bx, 1 shr bx, 1 ; BX has (i-41) base 8 of byte number ; from the start of the (inode) map add bx, word ptr [systm] ; superblock free map size + 4 add bx, offset systm+4 ; is inode map offset in superblock ; DX (MQ) has a 1 in the calculated bit position ; BX (R2) has byte address of the byte with allocation bit retn imap endp itrunc proc near ; 01/12/2012 ; unix boot file configuration version ; of "itrunc" procedure of retro unix v1.0 by Erdogan Tan ; Derived from (original) UNIX v1 source code ; PRELIMINARY release of Unix Implementation Document, ; 20/6/1972 ; ('itrunch' procedure) ; ; INPUT -> AX (R1) = inode number ; Return -> CF = 0 -> Successed, CF = 1 -> failed ; (error code in AX) call i_get ; jsr r0,iget jc short @f mov si, offset inode_dskp ; mov $i.dskp,r2 mov di, si itrunc_1: lodsb ; mov (r2)+,r1 / move physical block number into r1 or ax,ax jz short itrunc_5 ; beq 5f push si ; mov r2,-(sp) test word ptr [inode_flgs], 1000h ; bit $10000,i.flgs / test large file bit? jz short itrunc_4 ; beq 4f / if clear, branch push ax ; mov r1,-(sp) / save block number of indirect block call dsk_rd ; jsr r0,dskrd / read in block, ; bx = Buffer offset ; 1st data word pointed to by r5 jc short @f mov cx, 256 ; mov $256.,r3 / move word count into r3 itrunc_2: mov ax, word ptr [BX] ; mov (r5)+,r1 ; / put 1st data word in r1; physical block number inc bx and ax, ax jz itrunc_3 ; beq 3f / branch if zero push cx ; mov r3,-(sp) / save r3, r5 on stack push bx ; mov r5,-(sp) call free ; jsr r0,free / free block in free storage map pop bx ; mov (sp)+,r5 pop cx ; mov (sp)+,r3 itrunc_3: loop itrunc_2 ; dec r3 / decrement word count ; bgt 2b / branch if positive pop ax ; mov (sp)+,r1 ; / put physical block number of indirect block itrunc_4: call free ; jsr r0,free / free indirect block pop si ; mov (sp)+,r2 itrunc_5: cmp si, offset inode_dskp + 16 ; cmp r2,$i.dskp+16. jb short itrunc_1 ; bne 1b ; / branch until all i.dskp entries check and word ptr [inode_flgs], 0EFFFh ; 1110111111111111b ; bic $10000,i.flgs / clear large file bit mov cx, 8 xor ax, ax mov word ptr [inode_size], ax ; clr i.size / zero file size ;mov di, offset inode_dskp rep stosw ; jsr r0,copyz; i.dskp; i.dskp+16. ; / zero block pointers call set_imod ; jsr r0,setimod ; / set i-node modified flag ;mov ax, word ptr [ii] ; mov ii,r1 @@: retn ; rts r0 itrunc endp free proc near ; 01/12/2012 ; unix boot file configuration version ; of "free" procedure of retro unix v1.0 by Erdogan Tan ; Derived from (original) UNIX v1 source code ; PRELIMINARY release of Unix Implementation Document, ; 20/6/1972 ; ('free' procedure) ; ; INPUT -> ax (R1) = physical block number ; Return -> CF = 0 -> Successed, CF = 1 -> failed ; ;push bx ; mov r2,-(sp) / save r2, r3 ;;push cx ; mov r3,-(sp) ;push dx ;call free_3 ; jsr r0,3f ; / set up bit mask and word no. in free storage map ; / for block free_3: ; 3 mov dx, 1 mov cx, ax ; mov r1,r2 / block number, k, = 1 and cx, 0Fh ; bic $!7,r2 / clear all bits but 0,1,2; r2 = (k) mod (8) ; clr r3 jz short @f ; bisb 2f(r2),r3 / use mask to set bit in r3 ; corresponding to / (k) mod 8 shl dx, cl @@: mov bx, ax ; mov r1,r2 / divide block number by 16 shr bx, 1 ; asr r2 shr bx, 1 ; asr r2 shr bx, 1 ; asr r2 shr bx, 1 ; asr r2 ; bcc 1f / branch if bit 3 in r1 was 0 i.e., ; bit for block is in / lower half of word ; swab r3 / swap bytes in r3; bit in ; upper half of word in free / storage map free_1: ; 1 shl bx, 1 ; asl r2 / multiply block number by 2; r2 = k/8 add bx, offset systm+2 ; add $systm+2,r2 ; / address of word of free storage map for drum ; / with block bit in it ; retn ; rts r0 (return from free_3) @@: or word ptr [BX], dx ; bis r3, (r2) ; / set free storage block bit; indicates free block ; 0 -> allocated ;;inc byte ptr [smod] ; incb smod / set super block modified for drum ;mov byte ptr [smod], 1 ; / set super block modified for drum ;pop dx ;pop cx ; mov (sp)+,r3 / restore r2, r3 ;pop bx ; mov (sp)+,r2 ; AX (R1) = Block number retn free endp Cursor_Pos: dw 0 PhysicalDriveNumber: db 0 FileHandle: dw 0 StartupFile_Name: db 66 dup(0) ;- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ; messages ;- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - UNIX_Welcome: db 0Dh, 0Ah db 'Retro UNIX 8086 v1 Startup File Configuration Utility' db 0Dh, 0Ah db '(c) Erdogan TAN 2012 - [ 05/03/2013]' db 0Dh,0Ah db 0Dh,0Ah db 'Usage: unixboot [Floppy Drive] ' db 0Dh,0Ah db 0Dh,0Ah db "Floppy Drive names:" db 0Dh,0Ah db 0Dh,0Ah db "fd0 (Floppy Disk 1, A:)", 0Dh, 0Ah db "fd1 (Floppy Disk 2, B:)", 0Dh, 0Ah db 0 Msg_DoYouWantToWrite: db 07h db 0Dh, 0Ah db 'Do you want to write Retro Unix v1 Startup File onto drive ', 0 UNIX_FD_Name: db 'fd' UNIX_FD_Number: db '0: ', 0 msg_yes_no: db '(Yes/No)? ', 0 msg_unix_drv_read_error: db 0Dh, 0Ah db "Drive not ready or read error!" db 0Dh, 0Ah, 0 Msg_File_Not_Found: db 0Dh, 0Ah db "File not found !" db 0Dh, 0Ah, 0 Msg_Not_Unix_FS: db 0Dh, 0Ah db "Drive has not got a Retro UNIX v1 FS !" db 0Dh, 0Ah, 0 Msg_deleting_sf: db 0Dh, 0Ah db "Deleting Retro UNIX FS startup file..." db 0 Msg_writing_sf: db 0Dh, 0Ah db "Writing Retro UNIX FS startup file..." db 0 Msg_DosFile_Name: db 0Dh, 0Ah db "DOS File Name : ", 0 Msg_StartupFile_Name: db 0Dh, 0Ah db "Startup File Name : ", 0 Msg_3dot_OK: db "..." Msg_OK: db ' OK.', 0Dh, 0Ah, 0 msg_YES: db ' YES' db 0 msg_NO: db ' NO' db 0 UNIX_CRLF: db 0Dh, 0Ah, 0 msg_unix_drv_write_error: db 0Dh, 0Ah db 'Drive not ready or write error!' db 0Dh, 0Ah db 0 msg_very_big_startup_file_size: db 0Dh, 0Ah db 'Very big boot file size !' db 0Dh, 0Ah db 0 msg_Startup_File_Exists: db 0Dh, 0Ah, 0Dh, 0Ah db 'Startup File is already configured ! ' msg_please_select_an_option: ;db 'Please select an option: ' db 0Dh, 0Ah db 0Dh, 0Ah db 'Press to change current startup file configuration.' db 0Dh, 0Ah db 'Press to see current startup file information.' db 0Dh, 0Ah db 'Press to exit.' db 0Dh, 0Ah, 0 msg_sf_configuration_reset_ok: ; 01/12/2012 db 0Dh, 0Ah db "Startup file configuration RESET is OK." db 0Dh, 0Ah, 0 msg_Delete_Startup_File: ; 01/12/2012 ;db 0Dh, 0Ah ;db 'Please select an option: ' ;db 0Dh, 0Ah db 0Dh, 0Ah db 'Press to reset startup file configuration without deleting file.' db 0Dh, 0Ah db 'Press to delete current startup file, also.' db 0Dh, 0Ah db 'Press to cancel.' db 0Dh, 0Ah, 0 msg_overwrite_question1: ; 1/12/2012 db 0Dh, 0Ah db 'Do you want to overwrite ' db 27h db 0 msg_overwrite_question2: db 27h db ' file ' db 0 RetryCount: dw 0 BOOT_FILE_NAME: db 9 dup(0) bf_make_datetime: dd 0 ; 25/11/2012 bf_i_number: dw 0 ; 25/11/2012 bootfile_inode: inode: inode_flgs: dw 801Eh ; Flags (1000000000011110b) inode_nlks: db 1 ; number of links inode_uid: db 0 ; user ID (0 = root) inode_size: dw 0 ; file size inode_dskp: dw 8 dup (0) ; indirect or contents blocks inode_ctim: dd 0 ; creation date & time inode_mtim: dd 0 ; modification date & time inode_reserved: dw 0 ; unused rw: db 0 imod: db 0 U: u_uid: db 0 u_namep: dw 0 u_dirp: dw 0 u_base: dw 0 u_off: dw 0 u_count: dw 0 u_nread: dw 0 u_dirbuf: db 10 dup(0) ii: dw 0 buff_s: dw 0 year: dw 1970 month: dw 1 day: dw 1 hour: dw 0 minute: dw 0 second: dw 0 DMonth: dw 0 dw 31 dw 59 dw 90 dw 120 dw 151 dw 181 dw 212 dw 243 dw 273 dw 304 dw 334 ; 30/11/2012 ;imin: dd 0 ;ihrs: dd 0 ;iday: dw 0 ;lday: dw 0 ;qday: dw 0 ;iyrs: dw 0 ;jday: dw 0 ;mday: dw 0 ; 25/11/2012 str_inode_number: db 0Dh, 0Ah db 'Startup File I-Number: ', 0 Decimal_i_no_str: db 6 dup (0) Str_startup_file_size: db 0Dh, 0Ah db 'Startup File Size : ', 0 Str_Bytes: db ' bytes', 0 Decimal_size_str: db 6 dup (0) Str_sf_date_time: db 0Dh, 0Ah db 'Creating Date & Time : ' Str_cday: db '00' db '/' Str_cmonth: db '00' db '/' Str_cyear: db '0000' db 20h, 20h Str_chour: db '00' db ':' Str_cminute: db '00' db ':' Str_csecond: db '00' db 0Dh, 0Ah db 'Last Modif. Date & Time : ' Str_mday: db '00' db '/' Str_mmonth: db '00' db '/' Str_myear: db '0000' db 20h, 20h Str_mhour: db '00' db ':' Str_mminute: db '00' db ':' Str_msecond: db '00' db 0Dh, 0Ah, 0 bootfile_CopyRight: db '(c) Erdogan TAN - 09/07/2013' db 1 dup (0) ;- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ; buffers ;- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - BSBUFFER: db 512 dup(0) systm: ; superblock db 512 dup(0) ReadBUFFER: db 512 dup(0) WriteBUFFER: db 512 dup(0) SizeOfFile equ $-100 UNIXBOOT ends end START_CODE