telnet.asm

Application sources:A084.ZIP

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;
;    TERMINAL
;
;    Compile with FASM for Menuet
;
   
use32
   
                org     0x0
   
                db      'MENUET00'              ; 8 byte id
                dd      38                      ; required os
                dd      START                   ; program start
                dd      I_END                   ; program image size
                dd      0x100000                ; required amount of memory
                                                ; esp = 0x7FFF0
                dd      0x00000000              ; reserved=no extended header
   
   
   
START:                          ; start of execution
   
    ; Clear the screen memory
    mov     eax, '    '
    mov     edi,text
    mov     ecx,80*30 /4
    cld
    rep     stosd
   
   
    call draw_window
   
   
still:
    ; check connection status
    mov  eax,53
    mov  ebx,6
    mov  ecx,[socket]
    int  0x40
    
    mov     ebx, [socket_status]
    mov     [socket_status], eax
    
    cmp     eax, ebx
    je      waitev

    call    draw_window
    
waitev:
    mov  eax,23                 ; wait here for event
    mov  ebx,20
    int  0x40
   
    cmp  eax,1                  ; redraw request ?
    je   red
    cmp  eax,2                  ; key in buffer ?
    je   key
    cmp  eax,3                  ; button in buffer ?
    je   button

    ; any data from the socket?

    mov     eax, 53
    mov     ebx, 2
    mov     ecx, [socket]
    int     0x40
    cmp     eax, 0
    jne      read_input
   
    jmp  still
   
   
read_input:
   
    push ecx
    mov     eax, 53
    mov     ebx, 3
    mov     ecx, [socket]
    int     0x40
    pop  ecx

    call    handle_data   

    push    ecx
    mov     eax, 53
    mov     ebx, 2
    mov     ecx, [socket]
    int     0x40
    pop     ecx
    cmp     eax, 0


    jne   read_input
    call draw_text
    jmp  still


   
handle_data:
    ; Telnet servers will want to negotiate options about our terminal window
    ; just reject them all.
    ; Telnet options start with the byte 0xff and are 3 bytes long.
    
    mov     al, [telnetstate]
    cmp     al, 0
    je      state0
    cmp     al, 1
    je      state1
    cmp     al, 2
    je      state2
    jmp     hd001

state0:
    cmp     bl, 255
    jne     hd001
    mov     al, 1
    mov     [telnetstate], al
    ret

state1:
    mov     al, 2
    mov     [telnetstate], al
    ret
    
state2:
    mov     al, 0
    mov     [telnetstate], al
    mov     [telnetrep+2], bl
        
    mov     edx, 3
    mov     eax,53
    mov     ebx,7
    mov     ecx,[socket]
    mov     esi, telnetrep
    int     0x40
    ret

hd001:
    cmp  bl,13                          ; BEGINNING OF LINE
    jne  nobol
    mov  ecx,[pos]
    add  ecx,1
  boll1:
    sub  ecx,1
    mov  eax,ecx
    xor  edx,edx
    mov  ebx,80
    div  ebx
    cmp  edx,0
    jne  boll1
    mov  [pos],ecx
    jmp  newdata
  nobol:
   
    cmp  bl,10                            ; LINE DOWN
    jne  nolf
   addx1:
    add  [pos],dword 1
    mov  eax,[pos]
    xor  edx,edx
    mov  ecx,80
    div  ecx
    cmp  edx,0
    jnz  addx1
    mov  eax,[pos]
    jmp  cm1
  nolf:
   
    cmp  bl,8                            ; BACKSPACE
    jne  nobasp
    mov  eax,[pos]
    dec  eax
    mov  [pos],eax
    mov  [eax+text],byte 32
    mov  [eax+text+60*80],byte 0
    jmp  newdata
   nobasp:
   
    cmp  bl,15                           ; CHARACTER
    jbe  newdata
    mov  eax,[pos]
    mov  [eax+text],bl
    mov  eax,[pos]
    add  eax,1
  cm1:
    mov  ebx,[scroll+4]
    imul ebx,80
    cmp  eax,ebx
    jb   noeaxz
    mov  esi,text+80
    mov  edi,text
    mov  ecx,ebx
    cld
    rep  movsb
    mov  eax,ebx
    sub  eax,80
  noeaxz:
    mov  [pos],eax
  newdata:
    ret   
   
   
  red:                          ; REDRAW WINDOW
    call draw_window
    jmp  still
   
  key:                          ; KEY
    mov  eax,2                  ; send to modem
    int  0x40
    
    mov     ebx, [socket_status]
    cmp     ebx, 4              ; connection open?
    jne     still               ; no, so ignore key

    shr  eax,8
    cmp  eax,178                ; ARROW KEYS
    jne  noaup
    mov  al,'A'
    call arrow
    jmp  still
  noaup:
    cmp  eax,177
    jne  noadown
    mov  al,'B'
    call arrow
    jmp  still
  noadown:
    cmp  eax,179
    jne  noaright
    mov  al,'C'
    call arrow
    jmp  still
  noaright:
    cmp  eax,176
    jne  noaleft
    mov  al,'D'
    call arrow
    jmp  still
  noaleft:
  modem_out:
  
    call    to_modem
    
    jmp  still
   
  button:                       ; BUTTON
    mov  eax,17
    int  0x40
    cmp  ah,1                   ; CLOSE PROGRAM
    jne  noclose

    mov  eax,53
    mov  ebx,8
    mov  ecx,[socket]
    int  0x40
    
     mov  eax,-1
     int  0x40
  noclose:
    cmp     ah, 2               ; Set IP
    jne     notip

    mov  [string_x], dword 78
    mov  [string_y], dword 276
    mov  [string_length], dword 15
    call read_string
    mov   esi,string-1
    mov   edi,ip_address
    xor   eax,eax
   ip1:
    inc   esi
    cmp   [esi],byte '0'
    jb    ip2
    cmp   [esi],byte '9'
    jg    ip2
    imul  eax,10
    movzx ebx,byte [esi]
    sub   ebx,48
    add   eax,ebx
    jmp   ip1
   ip2:
    mov   [edi],al
    xor   eax,eax
    inc   edi
    cmp   edi,ip_address+3
    jbe   ip1
    call draw_window

    
    jmp     still
    
notip:
    cmp     ah, 3               ; set port
    jne     notport

    mov  [string_x], dword 215
    mov  [string_y], dword 276
    mov  [string_length], dword 4
    call read_string
    mov   esi,string-1
    mov   edi,port
    xor   eax,eax
   ip11:
    inc   esi
    cmp   [esi],byte '0'
    jb    ip21
    cmp   [esi],byte '9'
    jg    ip21
    imul  eax,10
    movzx ebx,byte [esi]
    sub   ebx,48
    add   eax,ebx
    jmp   ip11
   ip21:
    mov   [edi],al
    inc   edi
    mov   [edi],ah
    call draw_window

    
    jmp     still
    
notport:
    cmp     ah, 4               ; connect
    jne     notcon

    mov     eax, [socket_status]
    cmp     eax, 4
    je     still    
    call    connect

    jmp     still
    
notcon:
    cmp     ah,5                ; disconnect
    jne     notdiscon

    call    disconnect    
    jmp  still

notdiscon:                      ; Echo Toggle
    cmp     ah, 6
    jne     still

    mov     al, [echo]
    not     al
    mov     [echo], al
    
    call    draw_window
    jmp     still   
   
arrow:
   
    push eax
    mov  al,27
    call to_modem
    mov  al,'['
    call to_modem
    pop  eax
    call to_modem
   
    ret
   
   
to_modem:
    pusha
    push    ax
    mov     [tx_buff], al
    mov     edx, 1
    cmp     al, 13
    jne     tm_000
    mov     edx, 2
tm_000:
    mov     eax,53
    mov     ebx,7
    mov     ecx,[socket]
    mov     esi, tx_buff
    int  0x40
    pop     bx
    mov     al, [echo]
    cmp     al, 0
    je      tm_001
    
    push    bx
    call    handle_data
    pop     bx
    
    cmp     bl, 13
    jne     tm_002
    
    mov     bl, 10
    call    handle_data
    
tm_002:
    call    draw_text
    
tm_001:        
    popa
    ret
   
   
   
disconnect:
    mov  eax,53
    mov  ebx,8
    mov  ecx,[socket]
    int  0x40