PAGE ,132 TITLE DXBOOT.ASM -- Dos Extender Startup Code ; Copyright (c) Microsoft Corporation 1988-1991. All Rights Reserved. ;**************************************************************** ;* * ;* DXBOOT.ASM - Dos Extender Startup Code * ;* * ;**************************************************************** ;* * ;* Module Description: * ;* * ;* This module contains real mode initialization code that * ;* initializes the dos extender itself. This includes * ;* allocating and initializing the descriptor tables, and * ;* relocating the dos extender for protected mode operation. * ;* * ;**************************************************************** ;* Revision History: * ;* * ;* 01/29/92 mattfe Build for MIPS * ;* 12/19/90 amitc NetHeapSize default made 4k from 8k * ;* 12/03/90 amitc Added support for 'Win30CommDriver' switch * ; in system.ini * ;* 10/09/90 earleh split LDT from GDT and reduced XMS handles * ;* needed to boot program to 1 * ;* 08/08/90 earleh DOSX and client privilege ring determined * ;* by equate in pmdefs.inc * ;* 05/07/90 jimmat Started VCPI related changes. * ;* 04/09/90 jimmat Detect if on 286 & 287 installed. * ;* 04/02/90 jimmat Added PM Int 70h handler. * ;* 09/27/89 jimmat Changes to use FindFile to locate child * ;* program. * ;* 08/29/89 jimmat Now hooks real mode Int 2Fh chain. * ;* 08/20/89 jimmat Removed A20 code since HIMEM version 2.07 * ;* now works properly across processor resets. * ;* 07/28/89 jimmat Int PM Int 30h & 41h to be ignored, not * ;* reflected to real mode. * ;* 07/14/89 jimmat Added call to EMMDisable * ;* 06/16/89 jimmat Ifdef'd combined DOSX/child .EXE code * ;* 05/22/89 jimmat Added Int 13h/25h/26h/67h hooks. * ;* 05/18/89 jimmat Added setting of real mode Int 30h hook. * ;* 03/31/89 jimmat Added Priv Level to selectors during * ;* relocation and removed some dead code. * ;* 03/15/89 jimmat Added INT 31h hook * ;* 03/11/89 jimmat Added support for TSS & LDT & ring 1 * ;* 03/07/89 jimmat Converted to use WDEB386 debugger * ;* 02/25/89 (GeneA): added support for combined exe file where * ;* the Dos Extender and the child reside in the same exe * ;* file. * ;* 02/17/89 (GeneA): fixed error handling code during init. * ;* 02/14/89 (GeneA): added initialization of INT15h vector, * ;* and changed segment limit of BIOS_CODE segment to * ;* 64k. * ;* 02/14/89 (GeneA): added code to copy protected mode code * ;* segment up into extended memory. Also code to allocate * ;* and copy GDT and IDT in extended memory. * ;* 01/31/89 (GeneA): reorganization of code. This module now * ;* contains only code for initializing the Dos Extender * ;* itself. * ;* 01/25/89 (GeneA): moved code for loading and relocating * ;* the child program here from dxinit.asm * ;* 01/24/89 (Genea): removed routines for hooking into real * ;* mode int 2Fh. (part of removing real mode int 2Fh * ;* interface from the dos extender). * ;* 12/13/88 (GeneA): created by moving code from DXINIT.ASM * ;* * ;**************************************************************** .286p .287 ; ------------------------------------------------------- ; INCLUDE FILE DEFINITIONS ; ------------------------------------------------------- .xlist .sall include segdefs.inc include gendefs.inc include pmdefs.inc include dpmi.inc ifdef WOW_x86 include vdmtib.inc endif include intmac.inc include dbgsvc.inc .list ; ------------------------------------------------------- ; GENERAL SYMBOL DEFINITIONS ; ------------------------------------------------------- ; ; This structure defines the format of the EXE file header. EXEHDR struc idExeFile dw ? ;magic number to identify EXE file cbLastPage dw ? ;number of bytes in last page of the file crgbFileLen dw ? ;number of 512 byte pages in the file clpRelocLen dw ? ;number of relocation entries in the table cparHdrSize dw ? ;number of 16 byte paragraphs in header cparMinAlloc dw ? cparMaxAlloc dw ? segStackInit dw ? ;initial stack segment offStackInit dw ? ;initial stack pointer wCheckSum dw ? offCodeInit dw ? ;initial program counter segCodeInit dw ? ;initial code segment wRelocOffset dw ? ;byte offset of relocation table idOverlay dw ? ;overlay number EXEHDR ends ; ; This structure defines the parameter block to the XMS driver block ; move function. XMSMOVE struc cbxmsLen dd ? ;length of memory block hxmsSource dw ? ;XMS source block handle oxmsSource dd ? ;source offset hxmsDest dw ? ;XMS destination block handle oxmsDest dd ? ;destination offset XMSMOVE ends NOP_OPCODE equ 090h ; NO-OP opcode IRET_OPCODE equ 0CFh ; IRET opcode FAR_JMP_OPCODE equ 0EAh ; JMP FAR opcode SHORT_JMP_OPCODE equ 0EBh ; JMP SHORT opcode ; ------------------------------------------------------- ; EXTERNAL SYMBOL DEFINITIONS ; ------------------------------------------------------- extrn PMIntr31:NEAR extrn PMIntr13:NEAR extrn PMIntr19:NEAR extrn PMIntr28:NEAR extrn PMIntr25:NEAR extrn PMIntr26:NEAR extrn PMIntr4B:NEAR extrn PMIntrDos:NEAR extrn PMIntrMisc:NEAR extrn PMIntrVideo:NEAR extrn PMIntrMouse:NEAR extrn PMIntrIgnore:NEAR extrn PMIntrEntryVector:NEAR extrn PMFaultEntryVector:NEAR extrn ReadINIFile:NEAR ifdef NEC_98 ; extrn PMIntrSound:NEAR ; for Sound Bios extrn PMIntrExDos:NEAR ; for Extend Dos Function extrn PMIntr11dummy:NEAR extrn PMIntrPrinter:NEAR extrn PMIntrCalTi:NEAR extrn PMIntrGraph:NEAR endif ;NEC_98 ; extrn EMMDisable:NEAR extrn FindFIle:NEAR ifdef WOW_x86 extrn NpxExceptionHandler:near extrn EndNpxExceptionHandler:near endif extrn RmUnsimulateProc:FAR extrn PmUnsimulateProc:FAR extrn PMFaultHandlerIRET:NEAR extrn PMFaultHandlerIRETD:NEAR extrn PMIntHandlerIRET:NEAR extrn PMIntHandlerIRETD:NEAR extrn PMDosxIret:NEAR extrn PMDosxIretd:NEAR extrn RMCallBackBop:FAR extrn RMtoPMReflector:FAR extrn RmSaveRestoreState:far extrn PmSaveRestoreState:far extrn RmRawModeSwitch:far extrn PmRawModeSwitch:far extrn DPMI_MsDos_API:far extrn VCD_PM_Svc_Call:far extrn XmsControl:far extrn HungAppExit:far DXPMCODE segment extrn CodeEndPM:NEAR externFP NSetSegmentDscr DXPMCODE ends ; ------------------------------------------------------- ; DATA SEGMENT DEFINITIONS ; ------------------------------------------------------- DXDATA segment extrn selGDT:WORD extrn segGDT:WORD extrn selIDT:WORD extrn segIDT:WORD extrn bpGDT:FWORD extrn bpIDT:FWORD extrn sysTSS:WORD extrn segPSP:WORD extrn selPSP:WORD extrn hmemDOSX:WORD extrn f286_287:BYTE extrn bpRmIVT:FWORD extrn fhExeFile:WORD extrn idCpuType:WORD extrn cdscGDTMax:WORD extrn rgbXfrBuf0:BYTE extrn rgbXfrBuf1:BYTE extrn clpRelocItem:WORD extrn plpRelocItem:WORD extrn lpfnXMSFunc:DWORD ifdef NEC_98 ; extrn fPCH98:BYTE ; PC-H98 flag extrn fNHmode:BYTE ; NHmode flag endif ;NEC_98 ; extrn lpfnUserMouseHandler:DWORD extrn fUsingHMA:BYTE ifdef WOW_x86 extrn rgwWowStack:word extrn FastBop:fword endif extrn pbHwIntrStack:word IFNDEF WOW_x86 extrn IretBopTable:BYTE ENDIF public fDebug fDebug db 0 szModName db 'DOSX',0 ;Our module name for use by WDEB386 if DEBUG public lpchFileName lpchFileName dd ? endif INIFileName db 'SYSTEM.INI',0 ;.INI file to read public NetHeapSize, Int28Filter INIKeywords label byte db '[standard]',0 db 'netheapsize',0 NetHeapSize dw 4 ;default is 8k db 'int28filter',0 Int28Filter dw 10 ;default is every 10th if DEBUG ;------------------------------------------------------------ public fTraceDOS db 'tracedos',0 fTraceDOS dw 0 public fTraceFault db 'tracefault',0 fTraceFault dw 0 public fTraceA20 db 'tracea20',0 fTraceA20 dw 1 public TrapDOS db 'trapdos',0 TrapDOS dw 0 db 'tableslow',0 fTablesLow dw 0 public fTraceReflect db 'tracereflect',0 fTraceReflect dw 0 public fTraceMode db 'tracemode',0 fTraceMode dw 0 endif ;DEBUG -------------------------------------------------------- db 0 szExeExtension db '.exe',0 ; The following set of variables are used when copying our Pmode data ; structures into a HIMEM-allocated block. public lmaIDT,lmaGDT,lmaDXPMCODE CBIDTOFF = 0 CBGDTOFF = CDSCIDTDEFAULT * 8 IFNDEF WOW_x86 CBDXPMCODEOFF = CBGDTOFF + GDT_SIZE ELSE ; ; Since we have no GDT for wow, we do not need space for it. ; CBDXPMCODEOFF = CBGDTOFF ENDIF CBTABLESIZE = CBDXPMCODEOFF .errnz CBIDTOFF and 0fh .errnz CBGDTOFF and 0fh .errnz CBDXPMCODEOFF and 0fh lmaIDT dd CBIDTOFF lmaGDT dd CBGDTOFF lmaDXPMCODE dd CBDXPMCODEOFF lmaLDT dd CBDXPMCODEOFF extrn rgwStack:WORD DXDATA ends DXSTACK segment extrn ResetStack:WORD DXSTACK ends ; ------------------------------------------------------- page ; ------------------------------------------------------- ; CODE SEGMENT VARIABLES ; ------------------------------------------------------- DXCODE segment ;************************************************************************ ; ; REMEMBER... any code segment variables defined in this file ; will be discarded after initialization. ; ;************************************************************************ extrn CodeEnd:NEAR extrn segDXCode:WORD extrn segDXData:WORD extrn selDgroup:WORD ErrMsg MACRO name extrn ER_&name:BYTE ERC_&name equ offset ER_&name ENDM ErrMsg CPUTYPE ErrMsg DXINIT ErrMsg PROTMODE ErrMsg NOHIMEM ErrMsg EXTMEM ErrMsg NOEXE extrn RMInt2FHandler:NEAR extrn PrevInt2FHandler:DWORD szWinKernel db 'krnl386.exe',0 lpfnPrevXMS dd 0 DXCODE ends DXPMCODE segment extrn selDgroupPM:WORD extrn segDXCodePM:WORD extrn segDXDataPM:WORD DXPMCODE ends ; ------------------------------------------------------- page DXCODE segment assume cs:DXCODE ; ------------------------------------------------------- ; MAIN INITIALIZATION ROUTINES ; ------------------------------------------------------- ; InitDosExtender -- This routine is the executive ; for initializing the dos extender. ; ; Input: none ; Output: various global tables and variables initialized. ; Dos Extender relocated for protected mode execution ; and moved into extended memory. ; Errors: returns CY set if error occurs, pointer to error message ; in DX ; Uses: assume ds:DGROUP,es:DGROUP,ss:NOTHING public InitDosExtender InitDosExtender: ; Init the key code & data segment variables. mov ax,cs mov segDXCode,ax mov ax,ds mov segDXData,ax mov selDgroup,ax push es mov ax,seg DXPMCODE mov es,ax assume es:DXPMCODE mov selDgroupPM,SEL_DXDATA or STD_RING mov segDXCodePM,cs mov segDXDataPM,ds pop es assume es:DGROUP ; Do an initial shrink of our program memory. This assumes that DXPMCODE ; is the last segment in program. mov bx,(offset DXPMCODE:CodeEndPM) + 10h shr bx,4 add bx,seg DXPMCODE sub bx,segPSP mov es,segPSP dossvc 4Ah push ds pop es ; Determine the type of CPU we are running on and make sure it is ; at least an 80286. call CheckCPUType cmp ax,2 jae indx14 mov ax,ERC_CPUTYPE jmp indx80 indx14: ; If running on a 286, see if there is a 287 coprocessor installed ifdef NEC_98 ; ;------------------- 90/08/15 -------------------- ;check N/H at system area BIOS_FLAG(0:501h) ;if H mode, fNHmode bit on. push es push ax mov ax,0 mov es,ax test byte ptr es:[501h],8h ;if Hmode jz not_Hmode mov fNHmode,0FFh ;Now! Running on Hmode!!! 90/07/07 not_Hmode: pop ax pop es ;------------------- 90/08/15 -------------------- ; If running on a 286, see if there is a 287 coprocessor installed cmp al,2 ;286 processor? jnz EMM_Disable test fNHmode,0FFh jz Copro_Nmode ;----- 90/07/04 in ----- ; check co-processor exist at memory-switch ;----------------- Hmode ----------------- push ds push bx ;;;;;;;; mov bx,0Eh mov bx,0E000h ;90/10/04 bug mov ds,bx mov bx,3FEAh mov al,byte ptr ds:[bx] pop bx pop ds test al,08h ;0=none,1=exists jmp Coprocessor Copro_Nmode: ;----------------- Nmode ----------------- push ds push bx ;;;;;;;; mov bx,0Ah mov bx,0A000h ;90/10/04 bug mov ds,bx mov bx,3FEAh mov al,byte ptr ds:[bx] pop bx pop ds test al,08h ;0=none,1=exists Coprocessor: jz EMM_Disable inc f286_287 ; yup, 286 & 287 EMM_Disable: else ;NEC_98 ; cmp al,2 ;286 processor? jnz @f int 11h ;math coprocessor installed? test al,2 jz @f ifndef WOW_x86 inc f286_287 ; yup, 286 & 287 endif @@: endif ;NEC_98 ; ; If on a 386 or greater, try to disable the EMM drivers we know about call EMMDisable ; Check if the machine is already running in protected mode. If so, we ; can't run. ifndef WOW_x86 smsw ax test ax,1 ;check the protected mode bit jz @f mov ax,ERC_PROTMODE jmp indx80 endif @@: ; Get the full pathname of our EXE file, it's needed in a couple of places call GetExeName jnc @F mov ax,ERC_DXINIT jmp indx80 @@: ; Determine if the real mode Int 28h vector points anywhere. If it doesn't ; then we don't need to reflect Int 28h calls from protected to real mode. ; The user can still override this by putting a Int28Filter= entry in ; SYSTEM.INI. push es mov ax,3528h int 21h assume es:NOTHING cmp byte ptr es:[bx],IRET_OPCODE ;Int 28h -> IRET? jne @f mov Int28Filter,0 ; yes, don't need to reflect @@: pop es assume es:DGROUP ; Read SYSTEM.INI for any parameter overrides - NOTE: requires GetExeName ; having been run first! mov bx,offset INIKeywords mov dx,offset INIFileName call ReadINIFile ; Check that the HIMEM.SYS driver is installed so that we can use it ; for extended memory management. call SetupHimemDriver jnc @F ; Himem is OK. mov ax,ERC_NOHIMEM jmp indx80 @@: ifdef NEC_98 ; push es xor ax, ax mov es, ax test byte ptr es:[458h], 80h ; if NESA jz not_MC mov fPCH98, 0FFh ; it's a NPC NESA not_MC: pop es assume es:DGROUP endif ;NEC_98 ; ; Hook the real mode int vectors mov ax,352Fh ;get previous Int 2Fh vector int 21h assume es:NOTHING mov word ptr [PrevInt2FHandler],bx mov word ptr [PrevInt2FHandler+2],es push ds pop es assume es:DGROUP mov ax,cs ;point to our rMode Int 2Fh mov ds,ax assume ds:NOTHING mov dx,offset DXCODE:RMInt2FHandler mov ax,252Fh int 21h push es pop ds assume ds:DGROUP ; Allocate and initialize the descriptor tables and TSS. cCall AllocateExtMem jnc indx20 mov ax,ERC_EXTMEM jmp indx80 indx20: push es push bx push dx push di push si ; ; Bop to initialize 32 bit support. ; mov di, sp ;original stack offset push SEL_DXPMCODE OR STD_RING push offset DXPMCODE:HungAppExit push SEL_DXPMCODE OR STD_RING push offset DXPMCODE:XmsControl push SEL_DXPMCODE OR STD_RING push offset DXPMCODE:DPMI_MsDos_API push SEL_DXPMCODE OR STD_RING push offset DXPMCODE:VCD_PM_Svc_Call push SEL_DXPMCODE OR STD_RING push offset DXPMCODE:PmRawModeSwitch push segDXCode push offset DXCODE:RmRawModeSwitch push SEL_DXPMCODE OR STD_RING push offset DXPMCODE:PmSaveRestoreState push segDXCode push offset DXCODE:RmSaveRestoreState mov bx,cdscGDTMax shl bx,3 dec bx push bx ;Initial LDT size push selGDT push SEL_DXPMCODE OR STD_RING ;pm reflector seg push segDXCode push offset DXCODE:RMtoPMReflector push segDXCode push offset DXCODE:RMCallBackBop push SEL_DXPMCODE OR STD_RING push offset DXPMCODE:PMDosxIretd push SEL_DXPMCODE OR STD_RING push offset DXPMCODE:PMDosxIret push SEL_DXPMCODE OR STD_RING push offset DXPMCODE:PMIntHandlerIRETD push SEL_DXPMCODE OR STD_RING push offset DXPMCODE:PMIntHandlerIRET push SEL_DXPMCODE OR STD_RING push offset DXPMCODE:PMFaultHandlerIRETD push SEL_DXPMCODE OR STD_RING push offset DXPMCODE:PMFaultHandlerIRET push SEL_DXCODE OR STD_RING push segDXCode push SEL_DXPMCODE OR STD_RING push offset DXPMCODE:PmUnsimulateProc push segDXCode push offset DXCODE:RmUnsimulateProc push word ptr CB_STKFRAME push segDXData mov si,sp ;pass stack offset DPMIBOP InitDosxRM mov sp, di ;restore stack ifdef WOW_x86 mov word ptr [FastBop],bx mov word ptr [FastBop + 2],dx mov word ptr [FastBop + 4],es endif pop si pop di pop dx pop bx pop es call InitGlobalDscrTable ;set up the GDT call SendDbgNotification ;tell NTSD about our segments call InitIntrDscrTable ;set up the IDT ifndef WOW_x86 ;bugbug call InitTaskStateSeg ;set up the TSS endif if DEBUG ; DOSX is written such that it does not require any segment fix ups for ; protected mode operation. This wasn't always the case, and it's easy ; to make create dependencies so the routine CheckDOSXFixUps exists in ; the debug version to check for segment fix ups in non-initialization ; code. call CheckDOSXFixUps jnc @F mov ax,ERC_DXINIT jmp short indx80 @@: endif ;DEBUG ; Move the Extended memory segment up into extended memory. mov dx,seg DXPMCODE call MoveDosExtender jc indx80 ; Move the GDT and IDT up into extended memory. call MoveDscrTables ; Parse the command line, and locate the child exe file call ParseCommandLine IFNDEF WHEN_COMMAND_COM_WORKS if WINDOWS ;-------------------------------------------------------- ; If this is a Windows specific version of DOSX, we only run one child EXE ; (krnl?86.exe). push ds push cs pop ds assume ds:NOTHING mov si,offset DXCODE:szWinKernel mov di,offset RELOC_BUFFER call strcpy pop ds assume ds:DGROUP endif ;WINDOWS ------------------------------------------------- call FindFile ;setup done by ParseCommandLine jnc indx70 mov ax,ERC_NOEXE jmp short indx80 indx70: ENDIF ; Initialized okay! clc jmp short indx90 ; Error occured. Free any extended memory blocks allocated and then ; return the error code. indx80: push ax ;save the error code ; ; If we have allocated an extended memory block, then free it. ; If we have allocated the HMA, then free it. ; mov dx,hmemDOSX or dx,dx jz @F xmssvc 0Dh xmssvc 0Ah @@: cmp fUsingHMA,0 je @F xmssvc 2 @@: indxEXIT: pop ax ;restore the error code stc ;set error flag indx90: ret ; ------------------------------------------------------- ; AllocateExtMem -- Allocates memory used by DOSX for ; system tables and protected mode ; code. ; Allocates a temporary buffer in ; DOS memory for building the ; IDT and GDT. ; Input: none ; Output: none ; Uses: Flags ; Error: Carry set if cannot allocate memory. ; ; History: ; 10/05/90 - earleh wrote it assume ds:DGROUP,es:NOTHING,ss:NOTHING cProc AllocateExtMem,, cBegin ; If there is sufficient XMS memory, increase the size of the GDT/LDT ; up to the max of 8k selectors. add word ptr lmaLDT,offset DXPMCODE:CodeEndPM adc word ptr lmaLDT+2,0 add word ptr lmaLDT,0Fh ;make sure LDT is para aligned adc word ptr lmaLDT+2,0 and word ptr lmaLDT,0FFF0h @@: xmssvc 08h ;Query Free Extended memory cmp dx,1024 ;is there more than 1 meg available? jb @f mov cdscGDTMax,CDSCMAXLDT ; yes, max out the GDT size @@: mov ax,cdscGDTMax xor dx,dx shl ax,3 adc dx,0 add ax,word ptr lmaLDT adc dx,word ptr lmaLDT+2 add ax,1023d adc dx,0 ; DX:AX = total extended memory needed shl dx,6 shr ax,10d or dx,ax ; DX = kbytes needed mov si,dx ; SI = kbytes needed xmssvc 09h ; allocate the XMS block or ax,ax jz axm_error mov hmemDOSX,dx xmssvc 0Ch ; lock it, DX:BX = address or ax,ax jz axm_error axm_address: add word ptr lmaIDT,bx ; relocate tables & Pmode code adc word ptr lmaIDT+2,dx add word ptr lmaGDT,bx adc word ptr lmaGDT+2,dx add word ptr lmaDXPMCODE,bx adc word ptr lmaDXPMCODE+2,dx add word ptr lmaLDT,bx adc word ptr lmaLDT+2,dx mov bx,(CDSCIDTDEFAULT + GDT_SELECTORS + 1) shr 1 dossvc 48h ; get a DOS block for building tables jc axm_error ; abort if error mov segIDT,ax mov selIDT,ax add ax,CDSCIDTDEFAULT shr 1 mov segGDT,ax mov selGDT,ax clc jmp axm_exit axm_error: stc axm_exit: cEnd ; ------------------------------------------------------- ; SetupHimemDriver -- This routine checks that an XMS driver ; is installed and sets up for calling it. ; ; Input: none ; Output: none ; Errors: returns CY set if no driver available ; Uses: AX, all other registers preserved assume ds:DGROUP,es:DGROUP,ss:NOTHING public SetupHimemDriver SetupHimemDriver proc near push bx push es ; Check to see if there is an XMS driver resident. mov ax,4300h int 2Fh cmp al,80h jnz sthd80 ; There is an XMS driver resident, so init for calling it. mov ax,4310h int 2Fh mov word ptr [lpfnXMSFunc],bx mov word ptr [lpfnXMSFunc+2],es ; Make sure this is the proper XMS/driver version xmssvc 0 ;returns XMS vers in ax, driver vers in bx cmp ax,300h ;assume okay if XMS 3.0 or above jae @f cmp ax,200h ;require at least XMS 2.00 jb sthd80 cmp bx,21Ch ;if XMS 2.x, require driver version 2.28+ jb sthd80 ; (himem used to have minor vers in decimal) @@: ; Verify that the XMS driver's A20 functions work xmssvc 5 ;local enable or ax,ax jz sthd80 xmssvc 7 ;query A20 push ax xmssvc 6 ;local disable or ax,ax pop ax ;recover query status jz sthd80 or ax,ax ;should be NZ, (A20 enabled status) jz sthd80 ; Looks good to me... clc jmp short sthd90 ; No XMS driver resident or wrong version or we couldn't enable A20. sthd80: stc sthd90: pop es pop bx ret SetupHimemDriver endp ; ------------------------------------------------------- ; MoveDosExtender -- This routine will move the Dos Extender ; protected mode segment up into extended memory. ; The himem driver function for moving memory blocks is used. ; The parameter block for this function is built in rgbXfrBuf0. ; ; Input: DX - real mode segment address of the segment to move ; Output: none ; Errors: returns CY set if error, Error code in AX ; Uses: AX used, all else preserved ; modifies rgbXfrBuf0 assume ds:DGROUP,es:NOTHING,ss:NOTHING public MoveDosExtender MoveDosExtender proc near push bx push cx push dx push si cmp fUsingHMA,0 je mvdx40 ; ; Our extended memory block is actually the HMA. Enable A20 and do ; the move ourselves. ; xmssvc 5 ;local enable push di push ds push es mov cx,offset DXPMCODE:CodeEndPM inc cx and cx,0FFFEh mov di,CBDXPMCODEOFF+10h xor si,si dec si mov es,si inc si mov ds,dx assume ds:NOTHING ; ; DS:SI = segIDT:0 ; ES:DI = 0FFFF:CBDXPMCODEOFF+10h ; CX = code size ; cld rep movsb pop es assume ds:DGROUP pop ds pop di xmssvc 6 ;local disable jmp mvdx65 mvdx40: ; Move the data up into extended memory using the XMS driver's function. mov si,offset DGROUP:rgbXfrBuf0 mov cx,offset DXPMCODE:CodeEndPM inc cx and cx,0FFFEh mov word ptr [si].cbxmsLen,cx mov word ptr [si].oxmsSource+2,dx ;real mode code segment address mov ax,hmemDOSX mov word ptr [si].hxmsDest,ax xor ax,ax mov word ptr [si].cbxmsLen+2,ax mov [si].hxmsSource,ax mov word ptr [si].oxmsSource,ax mov word ptr [si].oxmsDest,CBDXPMCODEOFF mov word ptr [si].oxmsDest+2,ax xmssvc 0Bh mvdx65: clc jmp short mvdx90 ; Error occured mvdx80: stc mvdx90: pop si pop dx pop cx pop bx ret MoveDosExtender endp ; ------------------------------------------------------- ; MoveDscrTables -- This routine will move the GDT ; and IDT up into extended memory. The himem driver ; function for moving memory blocks is used. The parameter ; block for this function is built in rgbXfrBuf0. ; ; Input: none ; Output: none ; Errors: returns CY set if error occurs. Error code in AX ; Uses: AX, all else preserved ; modifies rgbXfrBuf0 assume ds:DGROUP,es:NOTHING,ss:NOTHING public MoveDscrTables MoveDscrTables proc near push bx push si push es cmp fUsingHMA,0 je @F ; ; Our extended memory block is actually the HMA. Enable A20 and do ; the move ourselves. ; xmssvc 5 ;local enable push ds push di push cx mov cx,CBTABLESIZE mov di,10h xor si,si dec si mov es,si inc si mov ds,segIDT assume ds:NOTHING ; ; DS:SI = segIDT:0 ; ES:DI = 0FFFF:10 ; CX = tables size ; cld rep movsb pop cx pop di pop ds assume ds:DGROUP xmssvc 6 ;local disable clc jmp mvdt_ret @@: ; Move the GDT and IDT together. mov si,offset DGROUP:rgbXfrBuf0 mov word ptr [si].cbxmsLen,CBTABLESIZE mov word ptr [si].cbxmsLen+2,0 mov ax,segIDT mov word ptr [si].oxmsSource+2,ax mov ax,hmemDOSX mov word ptr [si].hxmsDest,ax xor ax,ax mov [si].hxmsSource,ax mov word ptr [si].oxmsSource,ax mov word ptr [si].oxmsDest,ax mov word ptr [si].oxmsDest+2,ax xmssvc 0Bh IFDEF WOW ; ; Move the initialized selectors from the gdt to the ldt ; mov word ptr [si].cbxmsLen,GDT_SIZE mov word ptr [si].cbxmsLen+2,0 mov ax,segGDT mov word ptr [si].oxmsSource+2,ax mov ax,hmemDOSX mov word ptr [si].hxmsDest,ax xor ax,ax mov word ptr [si].hxmsSource,ax mov word ptr [si].oxmsSource,ax mov word ptr [si].oxmsDest+2,ax mov word ptr [si].oxmsDest,CBTABLESIZE + offset DXPMCODE:CodeEndPM xmssvc 0Bh ENDIF mvdt_ret: mov es,segIDT ;free the low memory copy dossvc 49h pop es pop si pop bx ret MoveDscrTables endp ; ------------------------------------------------------- ; Send Debugger Notification SendDbgNotification proc near IFDEF WOW ; ; Send load notification to the debugger for DXDATA ; push 1 ; data push ds ; exe name push offset EXEC_DXNAME push ds ; module name push offset szModName push 0 push SEL_DXDATA OR STD_RING push DBG_SEGLOAD BOP BOP_DEBUGGER add sp,16 ; ; Send load notification to the debugger for DXCODE ; push 0 ; code push ds ; exe name push offset EXEC_DXNAME push ds ; module name push offset szModName push 1 push SEL_DXCODE OR STD_RING push DBG_SEGLOAD BOP BOP_DEBUGGER add sp,16 ; ; Send load notification to the debugger ; push 0 ; code push ds ; exe name push offset EXEC_DXNAME push ds ; module name push offset szModName push 2 push SEL_DXPMCODE OR STD_RING push DBG_SEGLOAD BOP BOP_DEBUGGER add sp,16 ENDIF ret SendDbgNotification endp ; ------------------------------------------------------- ; InitGlobalDscrTable -- This function will allocate a memory ; buffer from DOS and then initialize it as a global ; descriptor table. It will also initialize all global ; variables associated with GDT management. ; Descriptors in the range 0 - SEL_USER are given statically ; defined meanings. Descriptors from SEL_USER up are defined ; dynamically when a program is loaded or when dynamic memory ; management calls occur. ; ; NOTE: This routine works in real mode. The buffer where ; the GDT is built is in low memory. ; ; Input: AX - number of descriptors to initialize ; Output: none ; Errors: CY set if unable to obtain memory for the GDT ; Uses: AX used, all other registers preserved ; bpGDT initialized. assume ds:DGROUP,es:DGROUP,ss:NOTHING public InitGlobalDscrTable InitGlobalDscrTable proc near push bx push cx push dx push di push es mov word ptr [bpGDT+0],GDT_SIZE - 1 mov ax,word ptr lmaGDT mov word ptr [bpGDT+2],ax mov ax,word ptr lmaGDT+2 mov word ptr [bpGDT+4],ax ; ; Start by initializing the GDT to 0. ; mov cx,GDT_SIZE shr 1 mov es,segGDT assume es:NOTHING xor ax,ax mov di,ax rep stosw ; Next, initialize the statically defined descriptors. ; ; Set up a descriptor for our protected mode code. xor ax,ax ;AX = 0 mov dx,cs ;our code segment paragraph address call B_ParaToLinear ;convert to linear byte address mov cx,offset CodeEnd cCall NSetSegmentDscr, ; Set up another one, but ring 0 this time. Limit should be 0FFFFh ; or 386 reset to real mode will not work properly. mov cx,0FFFFh cCall NSetSegmentDscr, ; ; Set up one for the other segment, and a Ring 0 alias. ; mov cx,offset CodeEndPM mov bx,word ptr lmaDXPMCODE mov dx,word ptr lmaDXPMCODE+2 cCall NSetSegmentDscr, cCall NSetSegmentDscr, ifndef WOW_x86 cCall NSetSegmentDscr, else cCall NSetSegmentDscr, endif mov cx,0FFFFh ; Set up a descriptor for our protected mode data and stack area. mov dx,ds ;our data segment paragraph address call B_ParaToLinear ;convert to linear byte address cCall NSetSegmentDscr, IFNDEF WOW_x86 ; Set up descriptor for IRET HOOKS push dx push bx add dx,offset IretBopTable adc bx,0 cCall NSetSegmentDscr, pop bx pop dx ELSE ; Set up descriptor for IRET HOOKS push dx push bx add dx,offset FastBop adc bx,0 cCall NSetSegmentDscr, pop bx pop dx ENDIF IFNDEF WOW_x86 ; And another one of those for ring 0 cCall NSetSegmentDscr, ENDIF ; ; Set up descriptors pointing to our PSP and environment. mov dx,segPSP ;segment address of the PSP call B_ParaToLinear ;convert to linear byte address cCall NSetSegmentDscr, mov selPSP,SEL_PSP ; push es mov es,segPSP assume es:PSPSEG mov dx,segEnviron call B_ParaToLinear cCall NSetSegmentDscr, pop es assume es:nothing ; Set up a descriptor that points to the GDT. mov dx,word ptr [bpGDT+2] ;get the GDT linear byte address mov bx,word ptr [bpGDT+4] mov cx,word ptr [bpGDT+0] ;get the GDT segment size cCall NSetSegmentDscr, ; Set up a descriptor for the LDT and an LDT data alias. mov cx,cdscGDTMax ;get count of descriptors shl cx,3 dec cx mov dx,word ptr lmaLDT mov bx,word ptr lmaLDT+2 IFNDEF WOW_x86 cCall NSetSegmentDscr, ENDIF cCall NSetSegmentDscr, ; set up a readonly selector to the LDT for the wow kernel cCall NSetSegmentDscr, ; Set up descriptors pointing to the BIOS code and data areas mov cx,0FFFFH ; CX = 0FFFFH cCall NSetSegmentDscr, mov dx,40h*16 cCall NSetSegmentDscr, ; Set up a descriptor pointing to the real mode interrupt vector table. cCall NSetSegmentDscr, IFNDEF WOW_x86 ; Setup a selector and data alias for the TSS mov dx,ds ;get base address of TSS call B_ParaToLinear ; (it may not be para aligned) add dx,offset DGROUP:sysTSS adc bx,ax mov cx,(TYPE TSS286) - 1 cCall NSetSegmentDscr, cCall NSetSegmentDscr, ENDIF ; ; Pass address of HwIntr stack, and form pointer to lockcount in ; VdmTib. This enables us to coordinate stack switching with ; the nt kernel and the monitor. These components will switch ; the stack on Hw Interrupt reflection, dosx will switch it ; back at iret. ; push es mov ax,SEL_DXDATA or STD_RING mov es, ax mov bx, pbHwIntrStack DPMIBOP InitPmStackInfo pop es IFDEF WOW_x86 ; ; Create a code selector for the NPX emulation exception handler ; mov ax,offset EndNpxExceptionHandler sub ax,offset NpxExceptionHandler mov bx,offset DXPMCODE:NpxExceptionHandler add bx,word ptr lmaDXPMCODE mov dx,word ptr lmaDXPMCODE + 2 cCall NSetSegmentDscr, ENDIF clc ;worked! make sure CY is clear ; All done igdt90: pop es pop di pop dx pop cx pop bx ret InitGlobalDscrTable endp ; ------------------------------------------------------- ; InitIntrDscrTable -- This function will initialize the ; specified memory buffer as an Interrupt Descriptor Table, ; and set up all of the control variables associated with ; the IDT. ; ; NOTE: This routine works in real mode. The buffer where ; the IDT is built is in low memory. ; NOTE: The InitGlobalDscrTable function must be called before ; this function can be called. ; ; Input: AX - number of descriptors to initialize ; Output: none ; Errors: CY set if unable to obtain the memory required ; Uses: AX, all other registers preserved assume ds:DGROUP,es:DGROUP,ss:NOTHING public InitIntrDscrTable InitIntrDscrTable proc near push bx push cx push dx push si push di push es ifndef WOW_x86 ; Save the current pointer to the real mode interrupt vector table. sidt fword ptr bpRmIVT endif mov es,selIDT assume es:NOTHING mov cx,256 ;number of descriptors in table shl cx,3 ;convert to count of bytes dec cx ;compute segment size limit mov word ptr [bpIDT+0],cx mov dx,word ptr lmaIDT mov word ptr [bpIDT+2],dx mov bx,word ptr lmaIDT+2 mov word ptr [bpIDT+4],bx cCall NSetSegmentDscr, ; Fill the IDT with interrupt gates that point to the fault handler and ; interrupt reflector entry vector. xor di,di mov dx,offset DXPMCODE:PmIntrEntryVector mov cx,256 iidt23: mov es:[di].offDest,dx mov es:[di].selDest,SEL_DXPMCODE or STD_RING mov es:[di].cwParam,0 mov es:[di].arbGate,STD_TRAP ; BUGBUG- int gates not set up mov es:[di].rsvdGate,0 add dx,5 add di,8 loop iidt23 ; Now, fix up the ones that don't point to the interrupt reflector. ; BUGBUG In dxstrt.asm, these are x86 ONLY. mov es:[1h*8].offDest,offset PMIntrIgnore mov es:[3h*8].offDest,offset PMIntrIgnore ifdef NEC_98 ; mov es:[11h*8].offDest,offset PMIntr11dummy mov es:[18h*8].offDest,offset PMIntrVideo mov es:[1ah*8].offDest,offset PMIntrPrinter mov es:[1bh*8].offDest,offset PMIntr13 mov es:[1ch*8].offDest,offset PMIntrCalTi mov es:[1dh*8].offDest,offset PMIntrGraph mov es:[1fh*8].offDest,offset PMIntrMisc else ;NEC_98 ; mov es:[10h*8].offDest,offset PMIntrVideo mov es:[13h*8].offDest,offset PMIntr13 mov es:[15h*8].offDest,offset PMIntrMisc mov es:[19h*8].offDest,offset PMIntr19 endif ;NEC_98 ; mov es:[21h*8].offDest,offset DXPMCODE:PMIntrDos mov es:[25h*8].offDest,offset DXPMCODE:PMIntr25 mov es:[26h*8].offDest,offset DXPMCODE:PMIntr26 mov es:[28h*8].offDest,offset DXPMCODE:PMIntr28 mov es:[30h*8].offDest,offset DXPMCODE:PMIntrIgnore mov es:[31h*8].offDest,offset DXPMCODE:PMIntr31 mov es:[33h*8].offDest,offset DXPMCODE:PMIntrMouse mov es:[41h*8].offDest,offset DXPMCODE:PMIntrIgnore ifndef WOW_x86 mov es:[4Bh*8].offDest,offset DXPMCODE:PMIntr4B ifdef NEC_98 ; ; Sound BIOS Int D2h handler mov es:[0D2h*8].offDest,offset DXPMCODE:PMIntrSound ; Extended DOS Int DCh handler (KANA/KANJI) mov es:[0DCh*8].offDest,offset DXPMCODE:PMIntrExDos endif ;NEC_98 ; endif ; ; Set up the IDT, and dpmi32 state ; mov ax,es ; Idt selector mov bx,VDM_INT_16 DPMIBOP InitIDT mov ax,5 ; handler increment mov cx,SEL_DXPMCODE OR STD_RING mov dx,offset DXPMCODE:PmFaultEntryVector DPMIBOP InitExceptionHandlers .286p ; All done iidt90: pop es pop di pop si pop dx pop cx pop bx ret InitIntrDscrTable endp ; ------------------------------------------------------- ; ; InitTaskStateSeg -- This function initializes the ; TSS for the DOS Extender. ; ; Input: none ; Output: none ; Errors: returns CY if unable to allocate memory ; Uses: all registers preserved assume ds:DGROUP,es:DGROUP,ss:NOTHING public InitTaskStateSeg InitTaskStateSeg proc near push ax push cx push di ; As a start, zero out the TSS xor al,al mov cx,type TSS286 mov di,offset DGROUP:sysTSS rep stosb ; Set the LDT selector mov sysTSS.tss_ldt,SEL_LDT ; Set the ring 0 stack seg/pointer, we don't bother to set the others ; since nothing runs below DOSX's ring. Currently very little code runs ; ring 0 - just when switching between real/proteted modes. mov sysTSS.tss_ss0,SEL_DXDATA0 mov sysTSS.tss_sp0,offset DGROUP:ResetStack ; That's all it takes pop di pop cx pop ax clc ret InitTaskStateSeg endp ; ------------------------------------------------------- ; MISC. STARTUP ROUTINES ; ------------------------------------------------------- ; *** CheckCPUType - Set global variable for CPU type ; ; This routine relies on Intel-approved code that takes advantage ; of the documented behavior of the high nibble of the flag word ; in the REAL MODE of the various processors. The MSB (bit 15) ; is always a one on the 8086 and 8088 and a zero on the 286 and ; 386. Bit 14 (NT flag) and bits 13/12 (IOPL bit field) are ; always zero on the 286, but can be set on the 386. ; ; For future compatibility of this test, it is strongly recommended ; that this specific instruction sequence be used. The exit codes ; can of course be changed to fit a particular need. ; ; CALLABLE FROM REAL MODE ONLY ; ; ENTRY: NONE ; ; EXIT: AX holds CPU type ( 0=8086,80186; 2=80286; 3=80386; 4=80486 ) ; ; USES: AX, DS must point to DX data segment ; idCpuType initialized ; ; Modified: 07-31-90 Earleh added code from Kernel, originally ; supplied by Intel, to check for 80486. Added check ; for V86 mode just in case a Limulator or something ; is active. ; assume ds:DGROUP,es:NOTHING,ss:NOTHING public CheckCPUType CheckCPUType proc near .8086 pushf ; save flags during cpu test pushf pop ax ; flags to ax and ax, 0fffh ; clear bits 12-15 push ax ; push immediate is bad op-code on 8086 npopf ; try to put that in the flags pushf pop ax ; look at what really went into flags and ah,0f0h ; mask off high flag bits cmp ah,0f0h ; Q: was high nibble all ones ? mov ax, 0 jz cidx ; Y: 8086 .286p smsw ax test ax,1 ; Protected mode? jnz cid386 ; V86! Gotta be at least a 386. push 0f000h ; N: try to set the high bits npopf ; ... in the flags pushf pop ax ; look at actual flags and ah,0f0h ; Q: any high bits set ? mov ax, 2 ; at least 286 jz cidx ; N: 80286 - exit w/ Z flag set ; Y: 80386 - Z flag reset ; 386 or 486? See if we can set the AC (Alignment check) bit in Eflags ; Need to insure stack is DWORD aligned for this to work properly .386 cid386: mov ax, 3 push cx push ebx mov cx,sp ; Assume stack aligned and cx,0011b ; set "pop" count sub sp,cx ; Move to DWORD aligned pushfd ; save entry flags (DWORD) push dword ptr 40000h ; AC bit popfd pushfd pop ebx popfd ; Recover entry flags (DWORD) add sp,cx ; pop off alignment bytes test ebx,40000h ; Did AC bit set? pop ebx pop cx jz short cidx ; No, 386 .286p inc ax ; At least 80486... cidx: mov idCpuType,ax ;store CPU type in global npopf ; restore flags after cpu test CheckCPUType endp ; ------------------------------------------------------- ; B_ParaToLinear ; ; This function will convert a paragraph address in the lower ; megabyte of memory space into a linear address for use in ; a descriptor table. This is a local duplicate of the function ; ParaToLinear in DXUTIL.ASM. This is duplicated here to avoid ; having to make far calls to it during the initialization. ; ; Input: DX - paragraph address ; Output: DX - lower word of linear address ; BX - high word of linear address ; Errors: none ; Uses: DX, BX used, all else preserved assume ds:NOTHING,es:NOTHING,ss:NOTHING B_ParaToLinear proc near xor bh,bh mov bl,dh shr bl,4 shl dx,4 ret B_ParaToLinear endp if DEBUG ;------------------------------------------------------- ; ------------------------------------------------------- ; CheckDOSXFixUps -- This routine will check for segment fix ups ; in non-initialization code that need to be converted from ; a segment to selector. ; ; This routine works by opening the EXE file that we were ; loaded from and examining the relocation table. ; ; 10-09-90 Earleh modified so that references in initialization ; code are not edited. ; ; 11-12-90 JimMat renamed from RelocateDosExtender and it now ; only checks for fix ups in DEBUG version since all fix ups ; in post-initialization code have been removed. ; ; Input: none ; Output: none ; Errors: returns CY set if error occurs ; Uses: AX, all else preserved ; modifies lpchFileName assume ds:DGROUP,es:NOTHING,ss:DGROUP public CheckDOSXFixUps CheckDOSXFixUps proc near push bp mov bp,sp push bx push dx push si push di push es ; Find the path to our exe fie. mov word ptr [lpchFileName],offset EXEC_DXNAME mov word ptr [lpchFileName+2],ds ; Set up for reading the relocation table from the exe file. call B_InitRelocBuffer jc rldx90 ;get out if error ; Go down through the relocation table and for each fixup item, ; patch in our selector. mov bx,segPSP add bx,10h ;the relocation table items are relative ; to the initial load address of our program ; image which is immediately after the PSP rldx40: call B_GetRelocationItem ;get next relocation table entry jz rldx60 ;if end of table, get out mov di,ax ;offset of relocation item add dx,bx ;adjust relocation item segment for our load ; address mov es,dx ; ; ; Do not fixup instructions in initialization code. ; cmp dx,seg DXCODE jne rldx41 cmp di,offset DXCODE:CodeEnd jnc rldx40 rldx41: cmp dx,seg DXPMCODE jne rldx42 cmp di,offset DXPMCODE:CodeEndPM jnc rldx40 rldx42: mov ax,es:[di] ;get the current fixup contents cmp ax,seg DXCODE ;is it the mixed mode segment? jnz rldx44 extrn lCodeSegLoc:WORD cmp di,offset DXCODE:lCodeSegLoc ;special far jmp to flush jz rldx40 ; pre-fetch queue? ok if so. ; Shouldn't get here--tell developer he messed something up! int 3 ;**************************************** mov word ptr es:[di],SEL_DXCODE or STD_RING jmp short rldx40 rldx44: cmp ax,seg DXPMCODE ;is it the protected mode only segment jnz rldx40 ; Shouldn't get here--tell developer he messed something up! int 3 ;**************************************** mov word ptr es:[di],SEL_DXPMCODE or STD_RING jmp rldx40 ;and repeat for the next one ; We have gone through the entire relocation table, so close up the exe file rldx60: mov bx,fhExeFile dossvc 3Eh ; clc jmp short rldx90 ; ; Error occured rldx80: stc ; ; All done rldx90: pop es pop di pop si pop dx pop bx mov sp,bp pop bp ret CheckDOSXFixUps endp ; ------------------------------------------------------- ; B_InitRelocBuffer -- This routine will open the EXE ; file and initialize for reading the relocation table ; as part of relocating the program for protected mode ; execution. ; ; Input: lpchFileName - pointer to exe file name ; Output: none ; Errors: returns CY set if error occurs ; Uses: AX modified, all other registers preserved ; sets up static variables: ; clpRelocItem, plpRelocItem, fhExeFile ; modifies rgbXfrBuf1 at offset RELOC_BUFFER assume ds:DGROUP,es:NOTHING,ss:NOTHING public B_InitRelocBuffer B_InitRelocBuffer proc near push bx push cx push dx push si ; ; Open the EXE file. push ds lds dx,lpchFileName mov al,0 dossvc 3Dh ;attempt to open the exe file pop ds jc inrl80 ;get out if error occurs ; mov fhExeFile,ax ;store the file handle mov bx,ax ;file handle to BX also ; Read the EXE file header, so that we can get information about ; the relocation table. mov dx,offset RELOC_BUFFER mov si,dx mov cx,32 dossvc 3Fh jc inrl80 ;get out if error cmp ax,32 jnz inrl80 ; ; Get the important values from the exe file header. cmp [si].idExeFile,5A4Dh ;make sure it is an EXE file jnz inrl80 mov ax,[si].clpRelocLen ;number of relocation items mov clpRelocItem,ax mov plpRelocItem,0FFFFh ;init the pointer to the first one ; to a bogus value to force the initial ; buffer to be loaded ; ; Get the location of the relocation table, and move the file pointer ; to its start. xor cx,cx mov dx,[si].wRelocOffset mov al,cl dossvc 42h jnc inrl90 ; ; Error occured inrl80: stc ; ; All done inrl90: pop si pop dx pop cx pop bx ret B_InitRelocBuffer endp ; ------------------------------------------------------- ; B_GetRelocationItem -- This routine will return the next ; relocation table entry from the exe file being relocated. ; ; Input: none ; Output: AX - offset of relocation item pointer ; DX - segment of relocation item pointer ; Errors: returns ZR true if end of table and no more items ; Uses: AX, DX modified, all other registers preserved assume ds:DGROUP,es:NOTHING,ss:NOTHING public B_GetRelocationItem B_GetRelocationItem proc near push si ; cmp clpRelocItem,0 ;are there any relocation items left? jz gtrl90 ;get out if not ; ; Check if the buffer is empty. The buffer for the relocation table is ; at offset RELOC_BUFFER in the buffer rgbXfrBuf1, and is 512 bytes long. cmp plpRelocItem,offset RELOC_BUFFER + 512 jc gtrl40 ; ; The buffer is empty, so we need to read the next part of it in. push cx push bx push dx mov ax,clpRelocItem ;number of items left in file shl ax,2 ;multiply by size of relocation item jc gtrl22 ;check for overflow cmp ax,512 ;check if bigger than the buffer jc gtrl24 gtrl22: mov ax,512 ;use buffer size as size of transfer gtrl24: mov cx,ax mov dx,offset RELOC_BUFFER mov plpRelocItem,dx ;pointer to next reloc item to return mov bx,fhExeFile dossvc 3Fh pop dx pop bx jc gtrl28 ;if error occured cmp ax,cx ;or, if we didn't get as much as we asked jnz gtrl28 ; for, we have an error pop cx jmp short gtrl40 ; gtrl28: pop cx stc jmp short gtrl90 ; ; Get the next relocation item from the buffer. gtrl40: mov si,plpRelocItem lods word ptr [si] ;get the offset part of the reloc item mov dx,ax lods word ptr [si] ;get the segment part of the reloc item xchg dx,ax ;put offset in AX, and segment in DX mov plpRelocItem,si ;store the updated pointer dec clpRelocItem ;and bump the count down by 1 or si,si ;clear the zero flag ; ; All done. gtrl90: pop si ret B_GetRelocationItem endp endif ;DEBUG -------------------------------------------------------- ; ------------------------------------------------------- ; GetExeName -- This routine will put a copy of the complete ; path name to the dos extender's exe file. In a name ; buffer in rgbXfrBuf1. ; ; Input: none ; Output: EXEC_DXNAME buffer updated with complete pathname. ; Errors: returns CY set if environment not correctly built. ; Uses: all preserved assume ds:DGROUP,es:DGROUP,ss:DGROUP public GetExeName GetExeName proc near push ax push si push di push ds ; The name of the current program is stored at the end of the environment ; table. There are two bytes of 0 to indicate end of table, a byte ; with a 1 in it followed by another byte of 0 and then the null terminated ; string with the current program name. gtxe20: mov ds,segPSP assume ds:PSPSEG mov ds,segEnviron assume ds:NOTHING xor si,si gtxe22: lods byte ptr [si] ;get next byte from environment or al,al ;test if 0 jnz gtxe22 ;if not, keep looking lods byte ptr [si] ;get next byte or al,al ;see if it is 0 also jnz gtxe22 ; We have found the double 0 at the end of the environment. So ; we can now get the name. At the end of the environment is an ; argc, argv construct. (i.e. a word giving the count of strings ; followed by an array of strings). Under DOS, argc is always 1, ; so check that there is a word of 1 here. If not, this environment ; wasn't built correctly and we don't know what is here. lods word ptr [si] cmp ax,1 jnz gtxe80 ; We have the pointer to the name, now copy it. mov di,offset EXEC_DXNAME call strcpy clc jmp short gtxe90 ; We have an error. gtxe80: stc ;set error condition flag gtxe90: pop ds pop di pop si pop ax ret GetExeName endp ; ------------------------------------------------------- ; COMMAND LINE PARSING ROUTINES ; ------------------------------------------------------- ; ParseCommandLine -- This function will examine the dos ; command line that caused the Dos Extender to be exec'd ; and determine what the user wants done. It will set ; up the various buffers required for the child program ; to be loaded. ; ; NOTE: the child exe file name read from the command line ; is placed in RELOC_BUFFER in the case where the child ; name is specified on the command line. This buffer is ; used later when reading the relocation table while ; performing the fixups on the child. ; ; Input: none ; Output: AL - 0 if empty command line, else non-zero ; parse buffers in rgbXfrBuf1 set up. ; Errors: none ; Uses: AX, all else preserved assume ds:DGROUP,es:DGROUP,ss:NOTHING public ParseCommandLine ParseCommandLine proc near push si push di push ds mov ds,segPSP assume ds:PSPSEG mov si,81h ;pointer to command line in PSP ; Skip any white space in front of the child program name. prsc12: lods byte ptr [si] cmp al,' ' jz prsc12 dec si ; Copy the command line tail following the program name to the command ; line buffer for use when we load the child. prsc40: push si ;save current point in parse mov di,offset EXEC_CMNDLINE + 1 xor dl,dl ;count characters in command line tail prsc42: lods byte ptr [si] ;get the next character stos byte ptr [di] ;store it into the output buffer cmp al,0Dh ;is it the end of the line? jz prsc44 inc dl ;count the character jmp prsc42 prsc44: mov es:[EXEC_CMNDLINE],dl ;store the character count pop si ;restore the buffer pointer ; Now we want to set up the two default FCB's by letting DOS parse the ; first two parameters on the command line. mov di,offset EXEC_FCB0 mov al,1 dossvc 29h mov di,offset EXEC_FCB1 mov al,1 dossvc 29h prsc90: pop ds pop di pop si ret ParseCommandLine endp ; ------------------------------------------------------- ; strcpy -- copy a null terminated string. ; ; Input: DS:SI - pointer to source string ; ES:DI - pointer to destination buffer ; Output: ES:DI - pointer to end of destination string ; Errors: none ; Uses: DI modified, all else preserved assume ds:NOTHING,es:NOTHING,ss:NOTHING public strcpy strcpy proc near push ax push si stcp10: lods byte ptr [si] stos byte ptr [di] or al,al jnz stcp10 dec di pop si pop ax ret strcpy endp ; ------------------------------------------------------- ; strcmpi -- This function will perform a case insensitive ; comparison of two null terminated strings. ; ; Input: DS:SI - string 1 ; ES:DI - string 2 ; Output: ZR if the strings match, else NZ ; CY set if string 1 less than string 2 ; Errors: none ; Uses: all registers preserved assume ds:NOTHING,es:NOTHING,ss:NOTHING public strcmpi strcmpi proc near push si push di stcm20: mov al,byte ptr ds:[si] call toupper mov ah,al mov al,byte ptr es:[di] call toupper cmp ah,al jnz stcm90 or al,ah jz stcm90 inc si inc di jmp stcm20 stcm90: pop di pop si ret strcmpi endp ; ------------------------------------------------------- ; IsFileNameChar -- This function will examine the ; character in AL and determine if it is a legal character ; in an MS-DOS file name. ; ; Input: AL - character to test ; Output: ZR true if character is legal in a file name ; Errors: none ; Uses: all registers preserved assume ds:NOTHING,es:NOTHING,ss:NOTHING IsFileNameChar proc near push ax cmp al,20h ;is it a control character jbe isfc80 ;if so, it isn't valid cmp al,':' jz isfc80 cmp al,';' jz isfc80 cmp al,',' jz isfc80 cmp al,'=' jz isfc80 cmp al,'+' jz isfc80 cmp al,'<' jz isfc80 cmp al,'>' jz isfc80 cmp al,'|' jz isfc80 cmp al,'/' jz isfc80 cmp al,'"' jz isfc80 cmp al,'[' jz isfc80 cmp al,']' jz isfc80 xor al,al jmp short isfc90 ; Not a valid file name character isfc80: or al,0FFh isfc90: pop ax ret IsFileNameChar endp ; ------------------------------------------------------- ; toupper -- This function will convert the character ; in AL into upper case. ; ; Input: AL - character to convert ; Output: AL - upper case character ; Errors: none ; Uses: AL modified, all else preserved assume ds:NOTHING,es:NOTHING,ss:NOTHING public toupper toupper proc near cmp al,'a' jb toup90 cmp al,'z' ja toup90 sub al,'a'-'A' toup90: ret toupper endp ; ------------------------------------------------------- DXCODE ends ; ;**************************************************************** end