;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;                                                            ;;
;;                   SYSTEM CALL ENTRY                        ;;
;;                                                            ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

align 32
i40:
      push  ds es
      pushad
      cld

      mov   ax,word os_data
      mov   ds,ax
      mov   es,ax

      ; for syscall trace function
      call  save_registers

      ; load all registers in crossed order
      mov   edi,[esp+28] ; eax
      mov   eax,[esp+16] ; ebx
      mov   ebx,[esp+24] ; ecx
      mov   ecx,[esp+20] ; edx
      mov   edx,[esp+4]  ; esi
      mov   esi,[esp+0]  ; edi

      ; enable interupts  -  a task switch or an IRQ _CAN_ interrupt i40 handler
      sti
      push  eax
      and   edi,0xff
      call  dword [servetable+edi*4]
      pop   eax
      cli
      
      popad
      pop   es ds
      iretd

align 4
save_registers:
      mov   esi, [0x3010]
      mov   eax, [esi+0x4] ; load PID
      lea   esi, [esp+4]
      inc   [save_syscall_count]
      mov   edi,[save_syscall_count]
      and   edi,0xF
      shl   edi,6
      add   edi,save_syscall_data+32
      mov   [edi-32],eax
      mov   ecx,32 / 4
      cld
      rep   movsd
      ret

uglobal
  save_syscall_count  dd 0x0
endg

label save_syscall_data dword at 0x5000


iglobal
  ;;;;;;;;;;;;;;;;;;;;;;;;;;;;
  ;; SYSTEM FUNCTIONS TABLE ;;
  ;;;;;;;;;;;;;;;;;;;;;;;;;;;;

  align 4
  servetable:

      dd sys_drawwindow          ; 0-DrawWindow
      dd syscall_setpixel        ; 1-SetPixel
      dd sys_getkey              ; 2-GetKey
      dd sys_clock               ; 3-GetTime
      dd syscall_writetext       ; 4-WriteText
      dd delay_hs                ; 5-DelayHs
      dd syscall_openramdiskfile ; 6-OpenRamdiskFile
      dd syscall_putimage        ; 7-PutImage
      dd sys_button              ; 8-DefineButton
      dd sys_cpuusage            ; 9-GetProcessInfo
      dd sys_waitforevent        ; 10-WaitForEvent
      dd sys_getevent            ; 11-CheckForEvent
      dd sys_redrawstat          ; 12-BeginDraw and EndDraw
      dd syscall_drawrect        ; 13-DrawRect
      dd syscall_getscreensize   ; 14-GetScreenSize
      dd sys_background          ; 15-bgr
      dd sys_cachetodiskette     ; 16-FlushFloppyCache
      dd sys_getbutton           ; 17-GetButton
      dd sys_system              ; 18-System Services
      dd syscall_startapp        ; 19-StartApp
      dd sys_midi                ; 20-ResetMidi and OutputMidi
      dd sys_setup               ; 21-SetMidiBase,SetKeymap,SetShiftKeymap,.
      dd sys_settime             ; 22-setting date,time,clock and alarm-clock
      dd sys_wait_event_timeout  ; 23-TimeOutWaitForEvent
      dd syscall_cdaudio         ; 24-PlayCdTrack,StopCd and GetCdPlaylist
      dd sys_sb16                ; 25-SetSb16
      dd sys_getsetup            ; 26-GetMidiBase,GetKeymap,GetShiftKeymap,.
      dd sys_wss                 ; 27-SetWssMainVol and SetWssCdVol
      dd sys_sb16II              ; 28-SetSb16
      dd sys_date                ; 29-GetDate
;      dd syscall_readhd          ; 30-ReadHd - obsolete <diamond>
      dd undefined_syscall       ; 30-reserved
;      dd syscall_starthdapp      ; 31-StartHdApp - obsolete <diamond>
      dd undefined_syscall       ; 31-reserved
      dd syscall_delramdiskfile  ; 32-DelRamdiskFile
      dd syscall_writeramdiskfile; 33-WriteRamdiskFile
;      dd read_floppy_file        ; 34-ReadFloppyDrive - obsolete <diamond>
      dd undefined_syscall       ; 34-reserved
      dd syscall_getpixel        ; 35-GetPixel
      dd syscall_readstring      ; 36-ReadString (not yet ready)
      dd readmousepos            ; 37-GetMousePosition_ScreenRelative,.
      dd syscall_drawline        ; 38-DrawLine
      dd sys_getbackground       ; 39-GetBackgroundSize,ReadBgrData,.
      dd set_app_param           ; 40-WantEvents
      dd syscall_getirqowner     ; 41-GetIrqOwner
      dd get_irq_data            ; 42-ReadIrqData
      dd sys_outport             ; 43-SendDeviceData
      dd sys_programirq          ; 44-ProgramIrqs
      dd reserve_free_irq        ; 45-ReserveIrq and FreeIrq
      dd syscall_reserveportarea ; 46-ReservePortArea and FreePortArea
      dd display_number          ; 47-WriteNum
      dd display_settings        ; 48-SetRedrawType and SetButtonType
      dd sys_apm                 ; 49-Advanced Power Management (APM)
      dd random_shaped_window    ; 50-Window shape & scale
      dd syscall_threads         ; 51-Threads
      dd stack_driver_stat       ; 52-Stack driver status
      dd socket                  ; 53-Socket interface
      dd user_events             ; 54-User events
      dd sound_interface         ; 55-Sound interface
      dd write_to_hd             ; 56-Write a file to hd
;      dd delete_from_hd          ; 57-Delete a file from hd - obsolete <diamond>
      dd undefined_syscall       ; 57-reserved
      dd file_system             ; 58-Common file system interface
      dd sys_trace               ; 59-System call trace
      dd new_sys_ipc             ; 60-Inter Process Communication
      dd sys_gs                  ; 61-Direct graphics access
      dd sys_pci                 ; 62-PCI functions
      dd sys_msg_board           ; 63-System message board
      dd sys_resize_app_memory   ; 64-Resize application memory usage
      dd undefined_syscall       ; 65-UTF
      dd sys_process_def         ; 66-Process definitions - keyboard
      dd sys_window_move         ; 67-Window move or resize
      dd sys_internal_services   ; 68-Some internal services
      dd sys_debug_services      ; 69-Debug
      dd file_system_lfn         ; 70-Common file system interface, version 2

  times 255 - ( ($-servetable) /4 )  dd undefined_syscall

      dd sys_end                 ; -1-end application
endg