; ***************************************************************************** ; ; INT_21H.ASM [ TRDOS INT 21h Handler ] ; Copyright (C) 2005 Erdogan TAN [ 29/01/2005 ] Last Update: 08/11/2011 ; ; 05/11/2011, 07/11/2011 ; 10/07/2011, 07/08/2011, 04/09/2011, 05/09/2011, 19/09/2011, 24/09/2011 ; 09/04/2011, 10/04/2011, 14/04/2011, 15/04/2011, 17/04/2011, 05/07/2011 ; 19/02/2011, 26/02/2011, 05/03/2011, 12/03/2011, 13/03/2011, 27/03/2011 ; 27/01/2011, 03/02/2011, 07/02/2011, 08/02/2011, 11/02/2011, 16/02/2011 ; 14/11/2009 ; TRDOS.ASM (include INT_21H.ASM) ; ; ***************************************************************************** ; TRDOS Function Calls ; ; (Code optimization will be needed at the last stage...) trdos_int21h_routine: ; 19/02/2011 ; 03/02/2011 push ds pop word ptr CS:[INT_DS] push cs pop ds mov word ptr [Interrupt_Number], 21h ; 17/04/2011 pop word ptr [INT_IP] pop word ptr [INT_CS] mov word ptr [INT_SPBP], sp pop word ptr [INT_Flags] mov word ptr [INT_BP], bp mov word ptr [INT_SP], sp push ss pop word ptr [INT_SS] push es pop word ptr [INT_ES] mov word ptr [INT_SI], si mov word ptr [INT_DI], di mov word ptr [INT_BX], bx mov word ptr [INT_CX], cx mov word ptr [INT_DX], dx mov word ptr [INT_AX], ax push word ptr [INT_Flags] ; 19/02/2011 mov bp, word ptr [INT_SPBP] and word ptr [BP], 0FFFEh ; clc ; 08/11/2011 mov bp, word ptr [INT_BP] ; push word ptr [INT_CS] push word ptr [INT_IP] push word ptr [INT_DS] pop ds ; cmp ah, 9 jne short pass_int21h_printstr push dx push ax push bx mov ah, 0Fh ; Get Video Display Mode int 10h ;AH= Number of columns ;AL= Video mode ;BH= Current video page mov word ptr CS:[Program_VideoMode],ax mov byte ptr CS:[Program_VideoPage],bh loc_print_$: ; Print String (with $ terminator) ; Input -> DS:DX = String Address mov BX, DX mov AL, byte ptr [BX] ; DS:[BX] cmp AL,'$' je short loc_int21h_9h_return ; AL = $ : end of string mov AH,0Eh mov BX, word ptr CS:[Program_CharColorAtr] ; BH = Video page int 10h ; BIOS Service func ( ah ) = 0Eh ; Write char as TTY ;AL-char BH-page BL-color inc DX jmp short loc_print_$ loc_int21h_1h_getchar: ; Output: al, keyboard input with echo ; AL= ASCII Code ; AH= Scan Code push dx push ax xor ah,ah int 16h pop dx mov dl, al mov ax, dx push ax push bx jmp short loc_int21h_1h_echo loc_int21h_2h_printchar: ; Int 21h Function 2h Input: DL, char push dx push ax push bx loc_int21h_1h_echo: mov ah, 0Fh ; Get Video Display Mode int 10h ;AH= Number of columns ;AL= Video mode ;BH= Current video page mov word ptr CS:[Program_VideoMode],ax mov byte ptr CS:[Program_VideoPage],bh mov BL, byte ptr CS:[Program_CharColorAtr] mov AL, DL mov AH,0Eh int 10h ; BIOS Service func ( ah ) = 0Eh ; Write char as TTY ;AL-char BH-page BL-color loc_int21h_9h_return: pop bx pop ax pop dx loc_int21h_return_1: ; 05/11/2011 ; 03/02/2011 mov bp, word ptr CS:[INT_BP] ;sti iret loc_get_trdos_version: ; INT 21h Function AH= 30h ; Return: ; AL= Major version number ; AH= Minor version number ; BX:CX= Build Number mov ax, 10 ; TRDOS Version 1.0 xor bx, bx xor cx, cx jmp short loc_int21h_return_1 loc_get_return_code: ; INT 21h Function AH=4Dh, Get Return Code ; temporary xor ax,ax jmp short loc_int21h_return_1 pass_int21h_printstr: ; INT 21h Function: 0 = Terminate Program cmp ah, 0 je run_com_INT20h_handler ; INT 21h Function: 1 = Keyboard Input cmp ah, 1 je short loc_int21h_1h_getchar ; INT 21h Function: 2 = Display Output cmp ah, 2 je short loc_int21h_2h_printchar ; INT 21h Function: 4Ch = Terminate Program cmp ah, 4Ch je run_com_INT20h_handler cmp ah, 4Ah je loc_int21h_modify_alloc_mem cmp ah, 4Bh jne short loc_check_function_35h ; Temporary ;08/11/2011 Temporary or al, al jz loc_int21h_function_4Bh jmp loc_other_dos_functions ; loc_check_function_35h: cmp ah, 35h je loc_get_interrupt_vector ; SHORT cmp ah, 25h je loc_set_interrupt_vector ; short cmp ah, 2Ch je loc_int21h_get_time ; SHORT cmp ah, 2Dh je loc_int21h_set_time cmp ah, 2Ah je loc_int21h_get_date cmp ah, 2Bh je loc_int21h_set_date cmp ah, 30h je short loc_get_trdos_version cmp ah, 4Dh je short loc_get_return_code ; 04/09/2011 cmp ah, 48h je loc_int21h_allocate_memory cmp ah, 49h je loc_int21h_deallocate_memory ; 27/01/2011 cmp ah, 4Eh je loc_int21h_find_first_file ; cmp ah, 4Fh je loc_int21h_find_next_file ja loc_int21h_check_71h ; 08/11/2011 ; 26/02/2011 cmp ah, 3Dh je loc_int21h_open_file ; 05/03/2011 cmp ah, 3Eh je loc_int21h_close_file cmp ah, 3Fh je loc_int21h_read_file ; 13/03/2011 cmp ah, 3Ch je loc_int21h_create_file cmp ah, 40h je loc_int21h_write_file cmp ah, 0Ah je loc_int21h_buffered_keyboard_input ; 27/03/2011 cmp ah, 19h je loc_int21h_get_current_drive cmp ah, 47h je loc_int21h_get_current_directory ; 09/04/2011 cmp ah, 42h je loc_INT21h_seek_file ; 10/04/2011 cmp ah, 1Ah je loc_INT21h_set_DTA cmp ah, 41h je loc_INT21h_delete_file ; 05/09/2011 cmp ah, 7 je loc_int21h_direct_char_input cmp ah, 8 je loc_int21h_direct_char_input_ctrl_c ; 07/11/2011 cmp ah, 44h jne short loc_int21h_check_56h or al, al ; temporary 07/011/2011 jz loc_int21h_Device_IOCTL ; 08/11/2011 jmp short loc_other_dos_functions ;jmp dword ptr CS:[INT21h_Offset] loc_int21h_check_56h: ; 19/09/2011 cmp ah, 56h je loc_INT21h_rename_file loc_other_dos_functions: ; 17/04/2011 push cs pop ds jmp loc_invalid_function_call ; IFC.ASM loc_int21h_check_71h: ; 08/11/2011 cmp ah, 71h ja short loc_other_dos_functions jb short loc_int21h_check_56h xor al, al mov byte ptr CS:[INT21h_Err_Code], al mov bp, word ptr CS:[INT_SPBP] ; Flags or byte ptr [BP], 1 ; stc mov bp, word ptr CS:[INT_BP] iret loc_get_interrupt_vector: ; Get Interrupt Vector ; Input -> AL= Interrupt Number ; Output -> ES:BX= Interrupt Vector xor ah, ah mov bx, ax shl bx, 1 shl bx, 1 xor al, al push ds mov ds, ax mov es, word ptr [BX]+2 mov bx, word ptr [BX] pop ds jmp loc_int21h_return_2 loc_set_interrupt_vector: ; Set Interrupt Vector ; Input -> AL= Interrupt Number ; DS:DX= Interrupt Vector xor ah, ah push es push bx mov bx, ax shl bx, 1 shl bx, 1 xor al, al mov es, ax mov word ptr ES:[BX], dx mov word ptr ES:[BX]+2, ds pop bx pop es jmp short loc_int21h_return_2 loc_int21h_get_time: ; INT 21h Function AH= 2Ch ; Output: ; CH= Hour (0-23) ; CL= Minute (0-59) ; DH= Second (0-59) ; DL= Standard Time = 0 ; DL= Daylight Savings Time = 1 mov ah, 02h int 1Ah mov al, ch and al, 0Fh mov ah, ch shr ah,1 shr ah,1 shr ah,1 shr ah,1 aad mov ch, al mov al, cl and al, 0Fh mov ah, cl shr ah,1 shr ah,1 shr ah,1 shr ah,1 aad mov cl, al mov al, dh and al, 0Fh mov ah, dh shr ah,1 shr ah,1 shr ah,1 shr ah,1 aad mov dh, al jmp short loc_int21h_return_2 loc_int21h_set_time: ; INT 21h Function AH= 2Dh ; CH= Hour (0-23) ; CL= Minute (0-59) ; DH= Second (0-59) ; DL= Standard Time = 0 ; DL= Daylight Savings Time = 1 mov al, ch aam shl ah, 1 shl ah, 1 shl ah, 1 shl ah, 1 or ah,al mov ch, ah mov al, cl aam shl ah, 1 shl ah, 1 shl ah, 1 shl ah, 1 or ah,al mov cl, ah mov al, dh aam shl ah, 1 shl ah, 1 shl ah, 1 shl ah, 1 or ah,al mov dh, ah push cx push dx mov ah, 02h int 1Ah mov al, dl pop dx pop cx mov dl, al mov ah, 03h int 1Ah loc_int21h_return_3: xor ax, ax loc_int21h_return_2: ; 03/02/2011 ; 08/11/2011 CS: prefix mov bp, word ptr CS:[INT_BP] ;sti iret loc_int21h_get_date: ; INT 21h Function AH= 2Ah ; Output: ; CX= Year (1980-2099) ; DH= Month (1-12) ; DL= Day (1-31) mov ah, 04h int 1Ah mov al, ch and al, 0Fh mov ah, ch shr ah,1 shr ah,1 shr ah,1 shr ah,1 aad mov ch, al mov al, cl and al, 0Fh mov ah, cl shr ah,1 shr ah,1 shr ah,1 shr ah,1 aad mov cl, al mov al, ch mov ah, 100 mul ah xor ch, ch add ax, cx mov cx, ax mov al, dh and al, 0Fh mov ah, dh shr ah,1 shr ah,1 shr ah,1 shr ah,1 aad mov dh, al mov al, dl and al, 0Fh mov ah, dl shr ah,1 shr ah,1 shr ah,1 shr ah,1 aad mov dl, al jmp short loc_int21h_return_2 loc_int21h_set_date: ; INT 21h Function AH= 2Bh ; CX= Year (1980-2099) ; DH= Month (1-12) ; DL= Day (1-31) mov ax, cx mov cl, 100 div cl mov cl, ah mov ch, al mov al, cl aam shl ah, 1 shl ah, 1 shl ah, 1 shl ah, 1 or ah,al mov cl, ah mov al, ch aam shl ah, 1 shl ah, 1 shl ah, 1 shl ah, 1 or ah,al mov ch, ah mov al, dh aam shl ah, 1 shl ah, 1 shl ah, 1 shl ah, 1 or ah,al mov dh, ah mov al, dl aam shl ah, 1 shl ah, 1 shl ah, 1 shl ah, 1 or ah,al mov dl, ah mov ah, 05h int 1Ah jmp loc_int21h_return_3 loc_int21h_modify_alloc_mem: ; INT 21h Function AH= 4Ah ; Modify Allocated Memory ; Input: ES -> Address of the block ; (Paragraph) to modify allocation size ; BX: New allocation size in paragraphs (with 16 bytes unit) ; 04/09/2011 ; 15/04/2011 -> PuSh & PoP check and corrections ; 14/04/2011 push ds ;ps1 push cx ;ps2 push dx ;ps3 push bx ;ps4 ;push cs ;ps5 ;pop ds ;pp5 mov ax, bx xor dx, dx add ax, 15 mov cx, 16 div cx push ax ;ps5 ; new allocation size in 100h bytes mov ah, 1 ; 04/09/2011 -> return max. available block size mov bx, es call proc_return_memory_block_allocation_status ; 04/09/2011 pop bx ;pp5 ; pushed ax cmp cx, bx jnb short loc_int21h_modify_alloc_mem_continue loc_int21h_modify_alloc_mem_insuff_mem: ; 04/09/2011 pop ax ;pp4 shl cx, 1 shl cx, 1 shl cx, 1 shl cx, 1 push cx ;ps4 mov ax, 08h ; Insufficient memory loc_int21h_modify_alloc_mem_err_retn: push bp ;ps5 mov bp, word ptr CS:[INT_SPBP] ; Flags or byte ptr [BP], 1 ; stc pop bp ;pp5 loc_int21h_modify_alloc_mem_retn: pop bx ;pp4 pop dx ;pp3 pop cx ;pp2 pop ds ;pp1 iret loc_int21h_modify_alloc_mem_continue: cmp dx, bx je short loc_int21h_modify_alloc_mem_retn jb short loc_int21h_modify_alloc_mem_extend loc_int21h_modify_alloc_mem_shorten: ; shrink sub dx, bx shl dx, 1 shl dx, 1 shl dx, 1 shl dx, 1 mov bx, es add bx, dx ; mov ah, 1 call proc_deallocate_memory mov bx, es xor ax, ax jmp short loc_int21h_modify_alloc_mem_retn loc_int21h_modify_alloc_mem_extend: push cs ;ps5 pop ds ;pp5 xchg bx, dx sub dx, bx mov cx, dx ; allocation size (in 256 bytes) shl dx, 1 shl dx, 1 shl dx, 1 shl dx, 1 mov bx, es add bx, dx xor ah, ah ; allocation size in 256 bytes xor dx, dx ; no segment boundary check call proc_allocate_memory ;jc short loc_int21h_modify_alloc_mem_insuff_mem xor ax, ax jmp short loc_int21h_modify_alloc_mem_retn loc_int21h_allocate_memory: ; INT 21h Function AH= 48h ; Allocate Memory ; Input: BX -> Requested block size (in paragraphs) ; 04/09/2011 push ds ;ps1 push cx ;ps2 push dx ;ps3 push bx ;ps4 push cs ;ps5 pop ds ;pp5 xor dx, dx mov al, byte ptr [Int21h_MemAlloc] cmp al, 0FFh ;11111111b (8 allocations) jnb short loc_int21h_alloc_mem_insuff_mem push ax ;ps5 inc dh ; 1 mov cx, 8 loc_int21h_alloc_memory_shift: shr al, 1 jnc short loc_int21h_alloc_memory_shift_ok inc dl shl dh, 1 loop loc_int21h_alloc_memory_shift loc_int21h_alloc_memory_shift_ok: push dx ;ps6 mov ax, bx xor dx, dx add ax, 15 mov cl, 16 div cx mov cx, ax ; count of 256 bytes to be allocated pop ax ;pp6, pushed dx pop dx ;pp5, pushed ax or dl, ah ; OR alloc byte with new alloc bit add al, 0F8h ; Allocation code from F8 to FFh push dx ;ps5 xor ah, ah mov dx, 1 ; 512 byte boundary check ; 'and' result must be zero call proc_allocate_memory pop dx ;pp5 jc short loc_int21h_alloc_mem_insuff_mem_shift mov byte ptr [Int21h_MemAlloc], dl mov ax, bx jmp short loc_int21h_alloc_mem_retn loc_int21h_alloc_mem_insuff_mem_shift: shl dx, 1 shl dx, 1 shl dx, 1 shl dx, 1 loc_int21h_alloc_mem_insuff_mem: pop ax ;pp4 push dx ;ps4 ;max. possible alloc size in paragraphs mov ax, 08h ; Insufficient memory loc_int21h_alloc_mem_err_retn: push bp ;ps5 mov bp, word ptr CS:[INT_SPBP] ; Flags or byte ptr [BP], 1 ; stc pop bp ;pp5 loc_int21h_alloc_mem_retn: pop bx ;pp4 pop dx ;pp3 pop cx ;pp2 pop ds ;pp1 iret INT21h_MemAlloc: db 0 loc_int21h_deallocate_memory: ; INT 21h Function AH= 49h ; Deallocate Memory ; Input: ES -> Mem segment to be deallocated ; 04/09/2011 ;push ds ;ps1 push cx ;ps2 push dx ;ps3 push bx ;ps4 ;push cs ;ps5 ;pop ds ;pp5 mov bx, es xor ah, ah call proc_return_memory_block_allocation_status cmp al, 0F8h jb short loc_int21h_dealloc_mem_invalid_mem_block ;inc ah ; 1 mov ah, 1 ;mov bx, es call proc_deallocate_memory xor ah, ah mov cx, ax mov al, 1 sub cl, 0F8h jz short loc_int21h_dealloc_mem_shift_ok loc_int21h_dealloc_mem_shift: shl al, cl loc_int21h_dealloc_mem_shift_ok: not al and byte ptr CS:[Int21h_MemAlloc], al xor al, al loc_int21h_dealloc_mem_retn: pop bx ;pp4 pop dx ;pp3 pop cx ;pp2 ;pop ds ;pp1 iret loc_int21h_dealloc_mem_invalid_mem_block: mov ax, 09h ; Invalid memory block address push bp ;ps5 mov bp, word ptr CS:[INT_SPBP] ; Flags or byte ptr [BP], 1 ; stc pop bp ;pp5 jmp short loc_int21h_dealloc_mem_retn loc_int21h_function_4Bh: ; 08/11/2011 ; 14/11/2009 ; INT 21h Function AH= 4Bh ; Load and Run Executable File ; INPUT ; AL= Mode (AL=0 Normal execution) ; ES:BX= Pointer to parameters block ; BX+0 = EnvironmentSegment ; BX+2 = CommandTail ; BX+6 = not used (FCB_1) ; BX+10 = not used (FCB_2) ; DS:DX= DOS Dot File Name Address ; 03/02/2011 push dx push ax push cx push si push di push ds push bp ; 08/11/2011 push pos. change push es ; 08/11/2011 push bx ; 08/11/2011 mov word ptr CS:[StackPointer21h], sp mov word ptr CS:[StackSegment21h], ss inc byte ptr CS:[INT21h_4Bh] push cs pop es mov si, dx ; DS:SI -> ASCIIZ Pathname string beginning address ; 14/11/2009 call proc_check_exe_filename_ext jnc short loc_int21h_load_executable_file ; 08/11/2011 push cs pop ds xor ax, ax mov byte ptr [INT21h_Err_Code], al mov byte ptr [INT21h_FFF_Valid], al ; 05/02/2011 loc_int21h_4Bh_stc_iret: dec byte ptr [INT21h_4Bh] mov ss, word ptr [StackSegment21h] mov sp, word ptr [StackPointer21h] ; 03/02/2011 ; 08/11/2011 CS: prefix has been removed mov bp, word ptr [INT_SPBP] ; Flags or byte ptr [BP], 1 ; stc ; pop bx ; 08/11/2011 push pos. change pop es ; 08/11/2011 pop bp ; 08/11/2011 pop ds pop di pop si pop cx pop dx ;ax pop dx iret loc_int21h_load_executable_file: mov byte ptr CS:[EXE_ID], al mov cx, bx ; Char count of the file <= 12 mov di, offset INT21h_File_name push di rep movsb pop si push cs pop ds mov ax, 04h call proc_open_file jnc short loc_INT21h_run_loaded_executable_file ;27/01/2011 mov byte ptr [INT21h_Err_Code], al jmp short loc_int21h_4Bh_stc_iret loc_INT21h_run_loaded_executable_file: mov word ptr [Run_Segment], ax mov word ptr [Run_Offset], 100h ; 08/11/2011 push es push bx ; 24/09/2011 mov dx, ax mov ax, word ptr [PSP_Address] mov ds, dx mov bx, 22 ; pspParentId mov word ptr [BX], ax mov word ptr CS:[PSP_Address], dx ; 08/11/2011 pop si ; pushed bx pop ds ; pushed es push ds push si mov es, dx mov ax, word ptr [SI] ; Environment segment and ax, ax jna short loc_INT21h_rlef_move_cmd_tail loc_INT21h_rlef_move_env_segment: mov di, 44 ; pspEnvironment mov word ptr ES:[DI], ax loc_INT21h_rlef_move_cmd_tail: inc si inc si mov dx, word ptr [SI]+2 ; Command tail, segment or dx, dx jz short loc_INT21h_rlef_move_cmd_tail_ok mov ax, word ptr [SI] ; Command tail, offset mov si, ax mov ds, dx mov al, byte ptr [SI] or al, al ; Command tail byte count jz short loc_INT21h_rlef_move_cmd_tail_ok mov cx, 78 loc_INT21h_rlef_move_cmd_tail_next: mov di, 128 ; Command tail (PSP) lodsb stosb cmp al, 13 ; Carriage return jna short loc_INT21h_rlef_move_cmd_tail_ok loop loc_INT21h_rlef_move_cmd_tail_next mov al, 13 ; 0Dh stosb loc_INT21h_rlef_move_cmd_tail_ok: pop bx ; Pointer to open file size, offset pop es ; Pointer to open file size, segment mov ax, word ptr ES:[BX] mov dx, word ptr ES:[BX]+2 push cs pop ds mov word ptr [Run_File_Size], ax mov word ptr [Run_File_Size]+2, dx jmp loc_run_loaded_executable_file_INT21h_4Bh ;End Of INT 21h Function AH=4Bh Load & Run Executable File loc_INT21h_find_first_file: ; 07/08/2011 BugFix for attributes > 0 input ; 11/02/2011 ; 05/02/2011 ; 27/01/2011 ; INT 21h Function AH= 4Eh ; Find First File ; INPUT ; CX= Attributes ; DS:DX= Pointer to filename push es push ds push di push si push bx push dx push cx mov ax, 1 mov si, dx ; 07/08/2011 mov byte ptr CS:[INT21h_FFF_Attributes], cl ; call proc_set_working_path jc short loc_INT21h_find_first_file_stc_retn ; 03/02/2011 pop ax ; cx, attributes push ax or ax, ax jz short loc_INT21h_find_first_file_pass_attr mov ah, 10h test al, 8h jnz short loc_INT21h_find_first_file_chk_dir_attr or ah, 8h loc_INT21h_find_first_file_chk_dir_attr: and al, 10h ; Directory jz short loc_INT21h_find_first_file_pass_attr and ah, 8h xor al, al loc_INT21h_find_first_file_pass_attr: mov word ptr [INT21h_AttribMask], ax ; 05/02/2011 mov si, offset FindFile_Name call proc_find_first_file jc short loc_INT21h_find_first_file_stc_retn ; 07/08/2011 mov dx, 2 ; File not found loc_find_next_file_ok: ; 07/08/2011 mov al, byte ptr [INT21h_FFF_Attributes] or al, al jz short loc_INT21h_find_first_file_attr_ok xor al, 0FFh and al, cl jz short loc_INT21h_find_first_file_attr_ok mov ax, dx ; mov bp, word ptr [INT_SPBP] ; Flags or byte ptr [BP], 1 ; stc jmp short loc_INT21h_find_first_file_err_retn loc_INT21h_find_first_file_attr_ok: ;mov si, offset FindFile_DirEntry mov di, word ptr [DTA_Address] mov ax, word ptr [DTA_Address]+2 mov es, ax ;mov es, word ptr [DTA_Address]+2 ; 11/02/2011 mov cx, 21 xor al, al rep stosb ; add si, 11 ; DirEntry_Attr movsb add si, 10 ; DirEntry_WrtTime movsw movsw ; DirEntry_WrtDate add si, 2 movsw ; DirEntry_Filesize movsw mov si, offset FindFile_DirEntry call Get_File_Name ; ds - es exchange push cs pop ds inc byte ptr [INT21h_FFF_Valid] ; 05/02/2011 ; al = 0 loc_INT21h_find_first_file_err_retn: mov byte ptr [INT21h_Err_Code], al loc_INT21h_find_first_file_retn: push ax call proc_reset_working_path pop ax loc_INT21h_find_next_file_retn: pop cx pop dx pop bx pop si pop di mov bp, word ptr [INT_BP] pop ds pop es iret loc_INT21h_find_first_file_stc_retn: mov byte ptr [INT21h_Err_Code], al mov al, 2 ; mov ax, 2 loc_INT21h_find_next_file_stc_retn: ; 03/02/2011 mov bp, word ptr [INT_SPBP] ; Flags or byte ptr [BP], 1 ; stc ; jmp short loc_INT21h_find_first_file_retn loc_INT21h_find_next_file: ; 07/08/2011 ; 19/02/2011 ; 16/02/2011 (Call Find_Next_File) BugFix ; 11/02/2011 ; 08/02/2011 ; 07/02/2011 ; 05/02/2011 ; INT 21h Function AH= 4Fh ; Find Next File ; INPUT -> none push es push ds push di push si push bx push dx push cx push cs pop ds cmp byte ptr [INT21h_FFF_Valid], 0 ja short loc_find_next_file_check_cdrv mov ax, 18h mov bp, word ptr [INT_SPBP] ; Flags or byte ptr [BP], 1 ; stc jmp short loc_INT21h_find_next_file_retn loc_find_next_file_check_cdrv: ; 19/02/2011 mov bl, byte ptr [Current_Drv] xor bh, bh mov word ptr [SWP_DRV], bx mov dl, byte ptr [FindFile_Drv] cmp dl, bl jne short loc_find_next_file_chg_cdrv ; mov bh, byte ptr [Current_Drv] ; xor bl, bl xchg bh, bl mov si, offset Logical_DosDisks add si, bx jmp short loc_find_next_file_check_cdir1 loc_find_next_file_chg_cdrv: inc byte ptr [SWP_DRV_chg] call proc_change_current_drive jc loc_INT21h_find_next_file_load_sub_dir_err loc_find_next_file_check_cdir1: ; 19/02/2011 ; 08/02/2011 mov ax, word ptr [FindFile_DirCluster] mov dx, word ptr [FindFile_DirCluster]+2 mov cx, ax or cx, dx jnz short loc_find_next_file_check_cdir2 cmp byte ptr [Current_FATType], 2 ja short loc_find_next_file_stc_18h_retn1 cmp byte ptr [Current_FATType], 1 jb short loc_find_next_file_stc_18h_retn1 cmp byte ptr [DirBuff_ValidData], bl ; 0 jna short loc_INT21h_find_next_file_load_root_dir cmp ax, word ptr [DirBuff_Cluster] jne short loc_INT21h_find_next_file_load_root_dir cmp dx, word ptr [DirBuff_Cluster]+2 ;jne short loc_INT21h_find_next_file_load_root_dir je short loc_find_next_file_check_cdir_OK ;cmp byte ptr [Current_Dir_Level], 0 ;ja short loc_find_next_file_stc_18h_retn1 ;jna short loc_find_next_file_check_cdir_OK loc_INT21h_find_next_file_load_root_dir: inc byte ptr [SWP_DRV_chg] call proc_load_FAT_root_directory jnc short loc_find_next_file_check_cdir_OK mov byte ptr [INT21h_Err_Code], al jmp loc_INT21h_find_next_file_stc_retn loc_find_next_file_stc_18h_retn1: mov ax, 18h loc_find_next_file_stc_18h_retn2: mov byte ptr [INT21h_FFF_Valid], 0FFh jmp short loc_INT21h_find_next_file_load_sub_dir_err loc_INT21h_find_next_file_check_error_no: mov byte ptr [INT21h_FFF_Valid], 0 cmp al, 18h jne short loc_INT21h_find_next_file_load_sub_dir_err jmp short loc_find_next_file_stc_18h_retn2 loc_find_next_file_check_cdir2: cmp byte ptr [DirBuff_ValidData], bl ; 0 jna short loc_INT21h_find_next_file_load_sub_dir cmp ax, word ptr [DirBuff_Cluster] jne short loc_INT21h_find_next_file_load_sub_dir cmp dx, word ptr [DirBuff_Cluster]+2 je short loc_find_next_file_check_cdir_OK loc_INT21h_find_next_file_load_sub_dir: inc byte ptr [SWP_DRV_chg] cmp byte ptr [Current_FATType], 1 jnb short loc_INT21h_find_next_file_load_fat_dir loc_INT21h_find_next_file_load_fs_dir: call proc_load_FS_sub_directory jnc short loc_find_next_file_check_cdir_OK ; 07/02/2011 loc_INT21h_find_next_file_load_sub_dir_err: mov byte ptr [INT21h_Err_Code], al jmp loc_INT21h_find_next_file_stc_retn loc_INT21h_find_next_file_load_fat_dir: call proc_load_FAT_sub_directory jc short loc_INT21h_find_next_file_load_sub_dir_err loc_find_next_file_check_cdir_OK: mov ax, word ptr [INT21h_AttribMask] mov word ptr [FindFile_AttributesMask], ax xor cx, cx ; 16/02/2011 call proc_find_next_file jc short loc_INT21h_find_next_file_check_error_no ; 07/08/2011 mov dx, 18h ; No more files jmp loc_find_next_file_ok loc_INT21h_open_file: ; 26/02/2011 ; INT 21h Function AH= 3Dh ; Open File ; INPUT ; AL= File Access Value ; 0- File Open for reading ; 1- File opened for writing ; 2- File opened for reading and writing ; AL = 3,4,5 -> TRDOS extensions ; DS:DX= Pointer to filename (ASCIIZ) push es push ds push di push si push bx push dx push cx cmp al, 5 jna short loc_INT21h_open_file_valid_access_no mov ax, 12 ; Invalid access code push cs pop ds jmp short loc_INT21h_open_file_err_retn loc_INT21h_open_file_valid_access_no: push ax mov ax, 1 mov si, dx call proc_set_working_path pop cx jc short loc_INT21h_open_file_err_retn loc_INT21h_open_file_set_working_path_ok: ; push ds ; DS = CS mov ax, word ptr [PSP_Address] push ds mov ds, ax mov si, OF_OFL_SN ; 4 mov ah, byte ptr [SI] pop ds mov al, cl ; Access code mov si, offset FindFile_Name call proc_open_file jnc short loc_INT21h_open_file_retn loc_INT21h_open_file_err_retn: mov byte ptr [INT21h_Err_Code], al mov bp, word ptr [INT_SPBP] ; Flags or byte ptr [BP], 1 ; stc loc_INT21h_open_file_retn: push ax call proc_reset_working_path loc_INT21h_close_file_retn: loc_INT21h_read_file_retn: pop ax pop cx pop dx pop bx pop si pop di mov bp, word ptr [INT_BP] pop ds pop es iret loc_INT21h_close_file: ; 05/03/2011 ; INT 21h Function AH= 3Eh ; Close File ; INPUT ; BX= File Handle ; push es push ds push di push si push bx push dx push cx push ax push cs pop ds mov ax, bx call proc_close_file jnc short loc_INT21h_close_file_retn loc_INT21h_close_file_err_retn: loc_INT21h_read_file_err_retn: mov byte ptr [INT21h_Err_Code], al mov bp, word ptr [INT_SPBP] ; Flags or byte ptr [BP], 1 ; stc jmp short loc_INT21h_close_file_retn loc_INT21h_read_file: ; 13/03/2011 ; 05/03/2011 ; INT 21h Function AH= 3Fh ; Read from a File ; INPUT ; BX= File Handle ; CX= Number of bytes to read ; DS:DX= Buffer address push es push ds push di push si push bx push dx push cx mov ax, bx mov bx, dx xor dx, dx push ds pop es push cs ; 13/03/2011 pop ds ; call proc_read_file push cx ; Read count jnc short loc_INT21h_read_file_retn loc_INT21h_read_file_check_eof: cmp dh, 0FFh ; EOF sign jnb short loc_INT21h_read_file_retn pop ax push ax jmp short loc_INT21h_read_file_err_retn loc_int21h_create_file: ; 10/07/2011 ; 12/03/2011 ; INT 21h Function AH= 3Ch ; Create File ; INPUT ; CX= Attributes ; DS:DX= Address of zero terminaned path name push es push ds push di push si push bx push dx push cx mov ax, 1 mov si, dx call proc_set_working_path jc short loc_INT21h_create_file_stc_retn xor ax, ax mov si, offset FindFile_Name call proc_find_first_file jnc short loc_INT21h_create_file_access_denied loc_INT21h_create_file_chk_fff_err_no: cmp al, 02h ; File not found jne short loc_INT21h_create_file_stc_retn loc_INT21h_create_file_chk_file_type: pop cx ; File/Directory attributes push cx test cl, 08h ; Volume name jnz short loc_INT21h_create_file_access_denied mov si, offset FindFile_Name test cl, 10h ; Directory jnz short loc_INT21h_create_directory xor dx, dx xor ax, ax xor bx, bx ; 10/07/2011 call proc_create_file jc short loc_INT21h_create_file_stc_retn mov al, 1 ; Access code = 1 --> open file for writing mov si, offset FindFile_Name call proc_open_file jc short loc_INT21h_create_file_stc_retn loc_INT21h_create_file_no_error: mov byte ptr [INT21h_Err_Code], 0 loc_INT21h_create_file_retn: push ax call proc_reset_working_path loc_INT21h_write_file_retn: pop ax pop cx pop dx pop bx pop si pop di mov bp, word ptr [INT_BP] pop ds pop es iret loc_INT21h_create_directory: call proc_make_directory jc short loc_INT21h_create_file_stc_retn xor ax, ax ; File handle = 0 mov byte ptr [INT21h_Err_Code], al ; 0 jmp short loc_INT21h_create_file_retn loc_INT21h_create_file_access_denied: mov ax, 05h ; Access denied loc_INT21h_create_file_stc_retn: loc_INT21h_write_file_err_retn: mov byte ptr [INT21h_Err_Code], al mov al, 3 ; mov ax, 3 mov bp, word ptr [INT_SPBP] ; Flags or byte ptr [BP], 1 ; stc ; jmp short loc_INT21h_create_file_retn loc_INT21h_write_file: ; 13/03/2011 ; 05/03/2011 ; INT 21h Function AH= 40h ; Write to a File ; INPUT ; BX= File Handle ; CX= Number of bytes to write ; DS:DX= Buffer address push es push ds push di push si push bx push dx push cx mov ax, bx mov bx, dx xor dx, dx or cx, cx jnz short loc_INT21h_write_file_no_truncate loc_INT21h_write_file_truncate: dec dh loc_INT21h_write_file_no_truncate: xor di, di push ds pop es push cs ; 13/03/2011 pop ds ; call proc_write_file push cx ; Write count jnc short loc_INT21h_write_file_retn loc_INT21h_write_file_check_eof: cmp dh, 0FFh ; EOF sign jnb short loc_INT21h_write_file_retn pop ax push ax jmp short loc_INT21h_write_file_err_retn loc_INT21h_seek_file: ; 09/04/2011 ; INT 21h Function AH= 42h ; Move File Pointer ; INPUT ; AL= Moving method ; 0- Offset specified is from the beginning of the file ; 1- Offset specified is distance from the current file pointer ; 2- The pointer is moved to the end of file minus the specified offset ; BX= File Handle ; CX:DX= Distance to move, in bytes call proc_move_file_pointer jnc short loc_INT21h_seek_file_retn loc_INT21h_seek_file_err_retn: mov byte ptr [INT21h_Err_Code], al mov bp, word ptr [INT_SPBP] ; Flags or byte ptr [BP], 1 ; stc mov bp, word ptr [INT_BP] loc_INT21h_seek_file_retn: iret loc_INT21h_delete_file: ; 10/04/2011 ; INT 21h Function AH= 41h ; Delete File ; INPUT ; DS:DX= Pointer to filename (ASCIIZ) push es push ds push di push si push bx push dx push cx push ax mov ax, 1 mov si, dx call proc_set_working_path jc short loc_INT21h_delete_file_err_retn loc_INT21h_delete_file_set_working_path_ok: loc_int21h_delfile_find: mov si, offset FindFile_Name mov ax, 1800h ; Except volume label and dirs call proc_find_first_file jc short loc_INT21h_delete_file_err_retn loc_int21h_delfile_check_ambgfn: cmp bx, 0 ; Ambiguous filename chars used sign (BX>0) jna short loc_int21h_delfile_found loc_INT21h_delete_file_not_found: mov ax, 02h ; File not found jmp short loc_INT21h_delete_file_err_retn loc_int21h_delfile_found: and cl, 07h ; Attributes jz short loc_int21h_delfile_check_attrib_ok mov ax, 05h ; Access denied (Permission denied) jmp short loc_INT21h_delete_file_err_retn loc_int21h_delfile_check_attrib_ok: ; ch > 0 -> the long name is existing/yes mov byte ptr [LongName_EntryLength], ch loc_int21h_delfile_call_proc_del_file: mov bh, byte ptr [FindFile_Drv] mov bl, byte ptr [LongName_EntryLength] mov cx, word ptr [DirBuff_EntryCounter] ; ES:DI -> Directory buffer entry offset/address call proc_delete_file jnc short loc_INT21h_delete_file_retn loc_INT21h_delete_file_err_retn: pop dx ; pushed ax mov byte ptr [INT21h_Err_Code], al mov bp, word ptr [INT_SPBP] ; Flags or byte ptr [BP], 1 ; stc push ax loc_INT21h_delete_file_retn: call proc_reset_working_path loc_INT21h_rename_file_retn1: pop ax loc_INT21h_rename_file_retn2: pop cx pop dx pop bx pop si pop di mov bp, word ptr [INT_BP] pop ds pop es iret loc_INT21h_rename_file: ; 19/09/2011 ; INT 21h Function AH= 56h ; Rename File ; INPUT ; DS:DX= Pointer to old filename (ASCIIZ) ; ES:DI= Pointer to new filename (ASCIIZ) push es push ds push di push si push bx push dx push cx push ax xor al, al ; INT 21h Move file sign -> 0 mov si, dx call move_source_file_to_destination_file jnc short loc_INT21h_rename_file_retn1 loc_INT21h_rename_file_err_retn: pop dx ; pushed ax mov byte ptr [INT21h_Err_Code], al mov bp, word ptr [INT_SPBP] ; Flags or byte ptr [BP], 1 ; stc jmp short loc_INT21h_rename_file_retn2 loc_int21h_buffered_keyboard_input: ; 13/03/2011 ; INT 21h Function AH= 0Ah ; Buffered Keyboard Input ; INPUT ; DS:DX= Pointer to input buffer ; Offset 0 = Byte/Character count ; Offset 1 = Actual number of characters read ; Offset 2 = Buffer starting location push si push bx push dx push cx push ax mov si, dx mov al, byte ptr [SI] add si, 2 call proc_int21h_rw_char dec si mov byte ptr [SI], al pop ax pop cx pop dx pop bx pop si iret loc_int21h_get_current_drive: ; 27/03/2011 ; INT 21h Function AH= 19h ; Get Default Drive ; INPUT ; none ; OUTPUT ; AL = Drive number (0=A,1=B, 2=C, etc.) ; mov al, byte ptr CS:[Current_Drv] iret loc_int21h_get_current_directory: ; 27/03/2011 ; INT 21h Function AH= 47h ; Get Current Directory ; INPUT ; DS:SI= Pointer to buffer ; DL = Drive number (0=Default, 1=A,2=B, 3=C, etc.) ; push es push di push bx push cx push ax ; Perhaps the caller needs ax must not be changed !? call proc_get_current_directory ; DS:SI and DX are not changed, jnc -> ES=DS jc short loc_INT21h_get_current_dir_err_retn pop ax loc_INT21h_get_current_dir_retn: pop cx pop bx pop di pop es iret loc_INT21h_get_current_dir_err_retn: pop cx ; pushed ax mov byte ptr CS:[INT21h_Err_Code], al mov bp, word ptr CS:[INT_SPBP] ; Flags or byte ptr [BP], 1 ; stc mov bp, word ptr CS:[INT_BP] jmp short loc_INT21h_get_current_dir_retn loc_INT21h_set_DTA: ; 10/04/2011 ; INT 21h Function AH= 1Ah ; Set Disk Transfer Address ; INPUT ; DS:DX= Pointer to DTA push ax mov ax, ds mov word ptr CS:[DTA_Address], dx mov word ptr CS:[DTA_Address]+2, ax pop ax iret loc_int21h_direct_char_input: ; 05/09/2011 ; INT 21h Function AH= 07h ; Direct Character/Keyboard Input, no echo ; INPUT ; AH = 07h -> Direct char input, no ctrl-c check xor ah, ah ; 0 mov al, byte ptr CS:[INT21h_KeyCodeWaiting] or al, al jz short loc_int21h_direct_char_input_c1 mov byte ptr CS:[INT21h_KeyCodeWaiting], ah iret loc_int21h_direct_char_input_c1: ;xor ah, ah int 16h loc_int21h_direct_char_input_c2: and al, al jnz short loc_int21h_direct_keyboard_input_retn mov byte ptr CS:[INT21h_KeyCodeWaiting], ah loc_int21h_direct_keyboard_input_retn: iret loc_int21h_direct_char_input_ctrl_c: ; 05/09/2011 ; INT 21h Function AH= 08h ; Direct Character/Keyboard Input, no echo ; INPUT ; AH = 08h -> Direct char input, ctrl-c check xor ah, ah ; 0 mov al, byte ptr CS:[INT21h_KeyCodeWaiting] or al, al jz short loc_int21h_direct_char_input_ctrl_c1 mov byte ptr CS:[INT21h_KeyCodeWaiting], ah iret loc_int21h_direct_char_input_ctrl_c1: ;xor ah, ah int 16h cmp ax, 2E03h ; CTRL + C jne short loc_int21h_direct_char_input_c2 int 23h iret INT21h_KeyCodeWaiting: db 0 loc_int21h_Device_IOCTL: ; 07/11/2011 ; INT 21h Function AH= 44h ; Device IOCTL ; INPUT ; AH = 44h ; AL = Sub Functions ; BX = File handle ; AL<>0 are Invalid functions for now ! or al, al jnz short loc_int21h_Device_IOCTL_inv_sf loc_int21h_Device_IOCTL_sf0: cmp bx, 8 ja short loc_int21h_Device_IOCTL_inv_handle push bx or bl, bl jz short loc_int21h_Device_IOCTL_get_info dec bl shl bl, 1 shl bl, 1 shl bl, 1 shl bl, 1 loc_int21h_Device_IOCTL_get_info: add bx, offset Device_Files_List mov ax, word ptr CS:[BX] or ax, ax jz short loc_int21h_Dev_IOCTL_inv_hndl_pop_bx mov bx, word ptr CS:[BX+2] add bx, 4 push ds mov ds, ax mov dx, word ptr [BX] pop ds or dl, 192 ; ? ; bit 6 and 7 ; bit 6 = EOF on input ; bit 7 = set -> device file pop bx iret loc_int21h_Device_IOCTL_inv_sf: mov ax, 1 ; Invalid function number loc_int21h_Device_IOCTL_err_retn: mov byte ptr CS:[INT21h_Err_Code], al mov bp, word ptr CS:[INT_SPBP] ; Flags or byte ptr [BP], 1 ; stc mov bp, word ptr CS:[INT_BP] iret loc_int21h_Dev_IOCTL_inv_hndl_pop_bx: pop bx loc_int21h_Device_IOCTL_inv_handle: mov ax, 6 ; Invalid function number jmp short loc_int21h_Device_IOCTL_err_retn INT21h_File_Name: db 13 dup(0) INT21h_Err_Code: db 0 ; 05/02/2011 INT21h_AttribMask: dw 0 INT21h_FFF_Valid: db 0 ; 07/08/2011 INT21h_FFF_Attributes: db 0 proc_int21h_rw_char proc near ; 13/03/2011, derivation from BOOTFILE.ASM (03/01/2010) ; INPUT -> DS:SI= String Buffer ; AL = String buffer size or byte/char count ; OUTPUT -> DS:SI= Entered String (ASCIIZ) ; AL = Byte/Character count mov ah, al mov word ptr [Char_Count_Start], ax mov bx,7 mov ah,3 int 10h mov Word Ptr [Cursor_Pos], dx int21h_read_next_char: xor ah,ah int 16h and al,al jz short int21h_loc_arrow cmp al,0E0h je short int21h_loc_arrow cmp al,08h jne short int21h_char_return int21h_loc_back: mov bl,7 mov ah,3 int 10h cmp dl,byte ptr [Cursor_Pos] ja short int21h_prev_column int21h_loc_beep: mov ah, 0Eh mov al, 7 int 10h jmp short int21h_read_next_char int21h_prev_column: dec dl int21h_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 int21h_loc_write_it: mov bl,7 int 10h mov dx,word ptr [Cursor_Pos] jmp short int21h_read_next_char int21h_loc_arrow: cmp AH,4Bh je short int21h_loc_back cmp AH,53h je short int21h_loc_back jmp short int21h_read_next_char int21h_char_return: mov bl,7 mov ah,3 int 10h mov bl,dl sub bl,byte ptr [Cursor_Pos] cmp al,20h jb short int21h_loc_escape cmp bl,63 ja short int21h_loc_beep ; cmp al, "z" ; ja short int21h_read_next_char ; cmp al, "a" ; jb short int21h_pass_capitalize ; and al, 0DFh int21h_pass_capitalize: xor ah, ah mov word ptr [SI][BX],ax mov ah, 0Eh mov bl, 7 int 10h int21h_pass_escape: cmp al,0Dh je short int21h_loc_return int21h_pass_return: dec byte ptr [char_Count] jnz short int21h_read_next_char int21h_loc_return: mov bl,7 int 10h mov al,0Ah int 10h int21h_rw_exit: mov al, byte ptr [char_count_start] sub al, byte ptr [char_count] retn int21h_loc_escape: cmp al,1Bh jne short int21h_pass_escape stc jmp short int21h_rw_exit cursor_pos: dw 0 char_count_start: db 0 char_count: db 0 proc_int21h_rw_char endp ; End Of TRDOS Function Calls