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Text File | 1992-02-22 | 21.6 KB | 1,105 lines

page ,132 title crt0dat - DOS and Windows shared startup and termination ;*** ;crt0dat.asm - DOS and Windows shared startup and termination ; ; Copyright (c) 1985-1992, Microsoft Corporation. All rights reserved. ; ;Purpose: ; Shared startup and termination. ; ; NOTE: This source is included in crt0.asm for assembly purposes ; when building .COM startup. This is so the .COM startup resides ; in a single special object that can be supplied to the user. ; ;******************************************************************************* _NFILE_ = 20 ; Maximum number of file handles ifdef _QWIN _WFILE_ = 20 ; Maximum number of QWIN file handles endif ?DF = 1 ;; tell cmacros.inc we want to define our own segments .xlist include version.inc include cmacros.inc include msdos.inc include defsegs.inc include stdlib.inc .list ifndef _WINDOWS _DEBUGSCREEN equ 1 ; debug screen swapping endif ifdef FARSTACK ife sizeD error <You cannot have a far stack in Small or Medium memory models.> endif endif ifdef _COM_ if sizeC or sizeD error <Must use Small memory model for .COM files.> endif endif ;_COM_ CrtDefSegs <code,cdata,data> ifdef _DEBUGSCREEN CrtDefSegs <dbdata> endif ; _DEBUGSCREEN ifndef _WINDOWS CrtDefSegs <xiqcseg> endif CrtDefSegs <xifseg,xiseg,xoseg,xofseg,xpseg,xcseg,xcfseg> CrtDefSegs <xifcseg> ifdef _COM_ CrtDefSegs <emdata, emcode> endif ;_COM_ defGrp DGROUP ; define DGROUP codeOFFSET equ offset _TEXT: dataOFFSET equ offset DGROUP: page sBegin xifbseg xifbegin label byte ; Far initializers begin/end sEnd xifbseg sBegin xifeseg xifend label byte sEnd xifeseg sBegin xibseg xibegin label byte ; Initializers begin/end sEnd xibseg sBegin xieseg xiend label byte sEnd xieseg sBegin xifcbseg xifcbegin label byte ; far C++ constructors begin/end sEnd xifcbseg sBegin xifceseg xifcend label byte sEnd xifceseg sBegin xobseg xontab label byte ; atexit/onexit begin/end sEnd xobseg sBegin xoeseg xonend label byte sEnd xoeseg ife sizeC ; in large model _fatexit = atexit so table not needed sBegin xofbseg xfontab label byte ; far atexit/onexit begin/end sEnd xofbseg sBegin xofeseg xfonend label byte sEnd xofeseg endif sBegin xpbseg xpbegin label byte ; Pre-terminators begin/end sEnd xpbseg sBegin xpeseg xpend label byte sEnd xpeseg sBegin xcbseg xcbegin label byte ; C terminators begin/end sEnd xcbseg sBegin xceseg xcend label byte sEnd xceseg sBegin xcfbseg xcfbegin label byte ; C far terminators begin/end sEnd xifbseg sBegin xcfeseg xcfend label byte sEnd xcfeseg sBegin cdata ; floating point setup segment assumes ds,data dw 0 ; force segment to be at least 0's labelD <PUBLIC,_fpinit> ; public for signal fpmath dd 1 dup (?) ; linking trick for fp fpdata dd 1 dup (?) fpsignal dd 1 dup (?) ; fp signal message sEnd ifdef _DEBUGSCREEN sBegin dbdata ; assumes ds,data ; Used to do the running under externW __aDBswpflg ; a debugger screen swapping externW __aDBexit ; sEnd dbdata ; extrn __aDBdoswp:ABS ; endif ; _DEBUGSCREEN ifndef _WINDOWS sBegin xiqcseg labelW <PUBLIC,__qczrinit> ;* QC -Zr initializer call address dw 1 dup(?) sEnd xiqcseg endif ifdef _COM_ sBegin EmData labelB _EmDataLabel sEnd EmData sBegin EmCode globalW _EmDataSeg,0 sEnd EmCode else ;not _COM ifndef _WINDOWS EMULATOR_DATA segment para public 'FAR_DATA' EMULATOR_DATA ends EMULATOR_TEXT segment para public 'CODE' public __EmDataSeg __EmDataSeg dw EMULATOR_DATA EMULATOR_TEXT ends endif ;not _WINDOWS endif ;not _COM_ sBegin data assumes ds,data ifndef _WINDLL ; special C environment string labelB <PUBLIC,_acfinfo> cfile db '_C_FILE_INFO=' cfilex db 0 cfileln = cfilex-cfile endif ;!_WINDLL globalD _aintdiv,0 ; divide error interrupt vector save globalT _fac,0 ; floating accumulator globalW errno,0 ; initial error code globalW _umaskval,0 ; initial umask value ifndef _WINDLL ;=============== following must be in this order globalW _pspadr,0 ; psp:0 (far * to PSP segment) globalW _psp,0 ; psp:0 (paragraph #) ;=============== above must be in this order endif ;=============== following must be in this order ifdef _WINDOWS labelW <PUBLIC,_osversion> ; WIN version globalB _osmajor,0 globalB _osminor,0 labelW <PUBLIC,_dosversion> ; DOS version globalB _dosmajor,0 globalB _dosminor,0 else ;!_WINDOWS labelW <PUBLIC,_osversion> ; OS version labelB <PUBLIC,_dosvermajor> globalB _osmajor,0 labelB <PUBLIC,_dosverminor> globalB _osminor,0 endif ;_WINDOWS ;=============== above must be in this order ifdef _WINDOWS globalB _osmode,_WIN_MODE ; Windows globalB _cpumode,_PROT_MODE ; protect mode (default) else globalB _osmode,_DOS_MODE ; DOS globalB _cpumode,_REAL_MODE ; real mode endif labelW <PUBLIC,_oserr> globalW _doserrno,0 ; initial DOS error code ; ; --- I/O Data --- ; globalW _nfile,_NFILE_ ; maximum number of file handles ifdef _QWIN globalW _wfile,_WFILE_ ; maximum number of QWIN file handles globalW _wnfile,(_NFILE_+_WFILE_) ; maximum number of total file handles endif ifdef _WINDOWS labelB <PUBLIC,_osfile> db _NFILE_ dup (0) ; (no std files in windows) else labelB <PUBLIC,_osfile> db 3 dup (FOPEN+FTEXT) ; stdin, stdout, stderr db 2 dup (FOPEN) ; stdaux, stdprn db _NFILE_-5 dup (0) ; the other 15 handles endif ;_WINDOWS ifdef _QWIN labelB <PUBLIC,_wsfile> db (FOPEN+FTEXT+FDEV) ; stdin/out/err db _WFILE_-1 dup (0) ; the other QWIN handles ; Make sure _osfile and _wsfile are contiguous .ERRE offset _osfile+_NFILE_ EQ offset _wsfile endif ;_QWIN ifdef _QWIN ;Force in QWIN system extrn __qwinused:word ; QWIN used/notused flag endif ; --- End I/O Data --- globalW __argc,0 globalDP __argv,0 globalDP _environ,0 ; environment pointer labelD <PUBLIC,_pgmptr> ; pointer to program name dw dataOFFSET dos2nam ifdef _COM_ dw 0 ; No relocations in tiny model elseifdef _QC2 dw 0 ; No DGROUP references allowed elseifdef _WINDOWS dw 0 ; No DGROUP references allowed else ;DEFAULT dw DGROUP endif dos2nam db 0 ; dummy argv[0] for DOS 2.X ; signal related common data globalW _child,0 ; flag used to handle signals from child process ifndef _WINDOWS ;Overlay related data globalB _ovlflag,0 ;Overlay flag (0 = no overlays) globalB _intno,0 ;Overlay interrupt value (e.g., 3F) globalD _ovlvec,0 ;Address of original overlay handler endif ;!_WINDOWS globalB _exitflag,0 ; callable exit sEnd data page externNP _fptrap ifndef _WINDLL externP _cintDIV endif ifndef _WINDOWS externP _nullcheck endif ifdef FARSTACK ifdef _WINDOWS externP _GetDGROUP endif endif ifdef _QWIN externNP _wcexit ; exit the QWIN system endif ifdef _WINDLL extern __nearstub:near ; weak extern substitute extern __freefarheap(__nearstub):near ; free up all far heap mem extern __freebasedheap(__nearstub):near; free up all based heap mem endif if (_NFILE_ NE 20) ifdef _WINDOWS extern SETHANDLECOUNT:far ; set file count endif endif sBegin code assumes cs,code if sizeC global proc far endif page ;*** ;_cinit - C initialization ; ;Purpose: ; This routine performs the shared DOS and Windows initialization. ; The following order of initialization must be preserved - ; ; 1. Integer divide interrupt vector setup ; 2. Floating point initialization ; 3. Copy ;C_FILE_INFO into _osfile ; 4. Check for devices for file handles 0 - 4 ; 5. General C initializer routines ; ;Entry: ; ;Exit: ; ;Uses: ; ;Exceptions: ; ;******************************************************************************* cProc _cinit,<PUBLIC>,<> ifdef _WINDOWS ; add windows prolog/epilog code to far frames if sizeC cBegin else cBegin <nogen> endif ;sizeC else cBegin <nogen> ; no local frame to set up in standard libs endif ; _WINDOWS assumes ds,data ifndef FARSTACK assumes ss,data endif ifdef _COM_ ; ; Initialize the DGROUP portion of _pgmptr. We must do this at ; runtime since there are no load-time fixups in .COM files. ; mov word ptr [_pgmptr+2],ds ; init seg portion of _pgmptr endif ;_COM_ if (_NFILE_ NE 20) ; ; *** Increase File Handle Count *** ; ifdef _WINDOWS mov bx,_NFILE_ ; number of file handle to allow push bx call SETHANDLECOUNT ; issue the system call ;check for error here, if desired (AX equals number of files supported) else ; This code only works on DOS Version 3.3 and later. mov ah,67h ; system call number mov bx,_NFILE_ ; number of file handles to allow callos ; issue the system call ;check for error here, if desired (if carry set, AX equals error code) endif ; ; *** End Increase File Handle Count *** ; endif ; (_NFILE_ NE 20) ifndef _WINDLL ; 1. Integer divide interrupt vector setup mov ax,DOS_getvector shl 8 + 0 callos ; save divide error interrupt mov word ptr [_aintdiv],bx mov word ptr [_aintdiv+2],es push cs pop ds assumes ds,nothing mov ax,DOS_setvector shl 8 + 0 mov dx,codeOFFSET _cintDIV callos ; set divide error interrupt ifdef FARSTACK ifdef _WINDOWS callcrt _GetDGROUP mov ds, ax else mov ax, DGROUP mov ds, ax endif else push ss pop ds ; restore DS=DGROUP endif assumes ds,data endif ;!_WINDLL ; 2. Floating point initialization if memS ifdef _WINDOWS mov cx,word ptr [fpmath+2] jcxz nofloat_i else ;not _WINDOWS cmp word ptr [fpmath], 0 ; Note: make sure offset __fpmath != 0 je nofloat_i mov word ptr [fpmath+2], cs ; fix up these far addresses mov word ptr [fpsignal+2], cs ; in the small model math libs ifdef _COM_ mov [_EmDataSeg], cs mov ax, offset DGROUP:_EmDataLabel sub ax, offset EMULATOR_DATA:_EmDataLabel mov cl, 4 shr ax, cl add [_EmDataSeg], ax endif ;_COM_ endif ;not _WINDOWS else ;not memS mov cx,word ptr [fpmath+2] jcxz nofloat_i endif ;not memS ifdef _WINDLL xor si,si ; no environment in Win DLL else ;!_WINDLL mov es,[_psp] ; psp segment mov si,es:[DOS_ENVP] ; environment segment endif ;_WINDLL mov ax, word ptr [fpdata] mov dx, word ptr [fpdata+2] xor bx,bx ; (si) = environment segment call [fpmath] ; fpmath(0) - init jnc fpok jmp _fptrap ; issue "Floating point not loaded" ; error and abort fpok: ifndef _WINDLL mov ax, word ptr [fpsignal] mov dx, word ptr [fpsignal+2] mov bx,3 call [fpmath] ; fpmath(3) - set signal address endif ;!_WINDLL nofloat_i: ifndef _WINDLL ; 3. Copy _C_FILE_INFO= into _osfile ; fix up files inherited from parent using _C_FILE_INFO= mov es,[_psp] ; es = PSP mov cx,word ptr es:[DOS_envp] ; es = user's environment jcxz nocfi ; no environment !!! mov es,cx xor di,di ; start at 0 cfilp: cmp byte ptr es:[di],0 ; check for end of environment je nocfi ; yes - not found mov cx,cfileln mov si,dataOFFSET cfile repe cmpsb ; compare for '_C_FILE_INFO=' je gotcfi ; yes - now do something with it mov cx,07FFFh ; environment max = 32K xor ax,ax repne scasb ; search for end of current string jne nocfi ; no 00 !!! - assume end of env. jmp cfilp ; keep searching ; found _C_FILE_INFO= and transfer info into _osfile gotcfi: push es push ds pop es ; es = DGROUP pop ds ; ds = env. segment assumes ds,nothing assumes es,data mov si,di ; si = startup of _osfile info mov di,dataOFFSET _osfile ; di = _osfile block mov cl, 4 osfile_lp: lodsb sub al, 'A' jb donecfi shl al, cl xchg dx, ax lodsb sub al, 'A' jb donecfi or al, dl stosb jmp short osfile_lp donecfi: ifdef FARSTACK push es else push ss endif pop ds ; ds = DGROUP assumes ds,data nocfi: endif ;!_WINDLL ifndef _WINDOWS ; 4. Check for devices for file handles 0 - 4 ; ; Clear the FDEV bit (which might be inherited from C_FILE_INFO) ; and then call DOS to see if it really is a device or not ; mov bx,4 devloop: and _osfile[bx],not FDEV ; clear FDEV bit on principal mov ax,DOS_ioctl shl 8 + 0 ; issue ioctl(0) to get dev info callos jc notdev test dl,80h ; is it a device ? jz notdev ; no or _osfile[bx],FDEV ; yes - set FDEV bit notdev: dec bx jns devloop endif ;!_WINDOWS ; 5. General C initializer routines mov si,dataOFFSET xifbegin mov di,dataOFFSET xifend call farinitterm ; call the far initializers mov si,dataOFFSET xibegin mov di,dataOFFSET xiend call initterm ; call the initializers mov si,dataOFFSET xifcbegin mov di,dataOFFSET xifcend call farinitterm ; call far C++ constructors. ifdef _WINDOWS ; add epilog code to windows far frame if sizeC cEnd else ret cEnd <nogen> endif ;sizeC else ret cEnd <nogen> ; standard C libs endif ; _WINDOWS page ;*** ;exit(status), _exit(status), _cexit(void), _c_exit(void) - C termination ; ;Purpose: ; ; Entry points: ; ; exit(code): Performs all the C termination functions ; and terminates the process with the return code ; supplied by the user. ; ; _exit(code): Performs a quick exit routine that does not ; do certain 'high-level' exit processing. The _exit ; routine terminates the process with the return code ; supplied by the user. ; ; _cexit(): Performs the same C lib termination processing ; as exit(code) but returns control to the caller ; when done (i.e., does NOT terminate the process). ; ; _c_exit(): Performs the same C lib termination processing ; as _exit(code) but returns control to the caller ; when done (i.e., does NOT terminate the process). ; ; Termination actions: ; ; exit(), _cexit (): ; ; 1. call user's terminator routines ; 2. call C runtime preterminators ; ; _exit(), _c_exit(): ; ; 3. call C runtime terminators ; 4. perform _nullcheck() for null pointer assignment ; 5. terminate floating point ; 6. reset divide by zero interrupt vector ; 7. return to DOS or caller ; ; Notes: ; ; The termination sequence is complicated due to the multiple entry ; points sharing the common code body while having different entry/exit ; sequences. ; ;Entry: ; exit(), _exit() ; int status - exit status (0-255) ; ; _cexit(), _c_exit() ; <no input> ; ;Exit: ; exit(), _exit() ; <EXIT to DOS> ; ; _cexit(), _c_exit() ; Return to caller ; ;Uses: ; ;Exceptions: ; ;******************************************************************************* ifndef _WINDLL ; ;--- exit(): Full exit and term process --- ; public _exit _exit: cProc dummy1,<>,<> parmw status ; termination code cBegin xor cx,cx ; exit(): cl = 0, ch = 0 jmp short common1 ; join common code cEnd <nogen> ; ;--- _exit(): Quickie exit and term process --- ; public __exit __exit: cProc dummy2,<>,<> parmw status ; termination code cBegin mov cx,1 ; _exit(): cl = 1, ch = 0 jmp short common1 ; join common code cEnd <nogen> endif ;!_WINDLL if sizeC global endp endif ; ;--- _cexit(): Full exit and return to caller --- ; cProc _cexit,<PUBLIC>,<SI,DI> cBegin mov cx,(1 SHL 8) ; _cexit(): ch = 1, cl = 0 jmp short common1 ; join common code cEnd <nogen> ; ;--- _c_exit(): Quickie exit and return to caller --- ; cProc _c_exit,<PUBLIC>,<SI,DI> cBegin mov cx,(1 SHL 8)+1 ; _c_exit(): ch = 1, cl = 1 ;fall through ; ;--- Common entry point --- ; cx = entry value: ; cl = full vs quick exit path ; 0 = exit() code ; 1 = _exit() code ; ch = term process vs return to caller ; 0 = term process ; 1 = return to caller ; common1: ; all code paths join here assumes ds,data ifndef FARSTACK assumes ss,data endif ; ; save exit flag (used by terminators) ; mov [_exitflag],ch ; ; If _exit()/_c_exit(), jump over the initial termination processing ; cx = entry code ; push cx ; save entry code on top of stack or cl,cl ; cl != 0 means _exit()/_c_exit() jnz short common2 ; if _exit()/_c_exit(), jump down ;fall thru ; continue (exit, _cexit) ; 1. call user terminators ; (atexit/onexit processing) mov si,dataOFFSET xontab mov di,dataOFFSET xonend call initterm ; atexit/onexit table ife sizeC ; in large code, _fatexit = atexit so no need to walk far table mov si,dataOFFSET xfontab mov di,dataOFFSET xfonend call farinitterm ; far atexit/onexit table endif ; 2. call C runtime preterminators ; - flushall ; - rmtmp mov si,dataOFFSET xpbegin ; beginning of pre-terminators mov di,dataOFFSET xpend ; end of pre-terminators call initterm ifdef _QWIN ; ; Exit the QWIN system. We can't do this in the pre-terminators because ; we want to make sure flushall() gets called before _QWINExit. ; mov si,[status] push si call _wcexit add sp,2 endif ;_QWIN ifdef _DEBUGSCREEN ; ; Tell the debugger we are going to exit ; cmp __aDBswpflg,__aDBdoswp ; Are we under a debugger? jne @F ; No -- skip forward cCall __aDBexit ; Yes -- tell it we are exiting @@: endif ; _DEBUGSCREEN ; ;--- Common entry point --- ; common2: ; __exit() enters here ; 3. perform C terminators mov si,dataOFFSET xcbegin mov di,dataOFFSET xcend call initterm ; call the terminators mov si,dataOFFSET xcfbegin mov di,dataOFFSET xcfend call farinitterm ; call the far terminators ; 4. perform _nullcheck() for null pointer assignment ifndef _COM_ ; DS:0 is the PSP in .COM files! ifndef _WINDOWS ; Don't validate the copyright message in windows call _nullcheck ; check data in NULL data segment at DS:0 ; this must be far call in large code models ; since user can stub it out or ax,ax ; zero if no null ptr assignment detected jz afternullchk pop ax ; get entry code or ah,ah ; ah != 0 means _cexit()/_c_exit() push ax ; put it back for later jnz short afternullchk ; jump if no status value (_cexit/_c_exit) cmp status,0 ; zero if no other error has occurred jnz short afternullchk mov status,255 ; nonzero status to indicate an ; null-pointer-assignment error afternullchk: endif ;_WINDOWS endif ;_COM_ ; 5. terminate floating point ; 6. reset divide by zero interrupt vector call _ctermsub ; fast cleanup ifdef _WINDLL ; 6a. free up all global memory to the OS ; [NOTE 1: This is necessary because WINDLL memory is ; shared and windows won't reclaim it.] ; [NOTE 2: This routine must be called last because a ; terminator may reference the heap.] call __freefarheap ; free up far memory call __freebasedheap ; free up based memory endif ; 7. return to the DOS or caller ifdef _WINDLL ; Always return to caller (exit/_exit is illegal) pop ax ; clean off stack else pop ax ; get entry code off top of stack or ah,ah ; ah = 0 means term process jnz returning ; skip down if not term'ing ; 7a. return to the DOS exiting: mov ax,status ; get return value callos terminate ; exit with al = return code ;*** PROCESS IS TERMINATED *** endif ;_WINDLL ; 7b. Return to caller. returning: cEnd <nolocals> page ;*** ;_ctermsub - more C termination code ; ;Purpose: ; This routine ; (1) performs floating-point termination ; (2) resets the divide by zero interrupt vector ; (3) restore int 3F handler ; ;Entry: ; ;Exit: ; ;Uses: ; AX,BX,CX,DX. ; ;Exceptions: ; ;******************************************************************************* labelNP <PUBLIC,_ctermsub> ; 4. terminate floating point mov cx,word ptr [fpmath+2] ; test for floating point jcxz nofloat_t ; no mov bx,2 ; yes - cleanup call [fpmath] nofloat_t: ifndef _WINDLL ; 5. reset divide by zero interrupt vector push ds lds dx,[_aintdiv] ; ds:dx = restore vector mov ax,DOS_setvector shl 8 + 0 callos ; set divide error interrupt pop ds endif ;!_WINDLL ret page ;*** ;initterm - do a set of initializers or terminators ; ;Purpose: ; The initializors and terminators may be written in C ; so we are assuming C conventions (DS=SS, CLD, SI and DI preserved) ; We go through them in reverse order for onexit. ; ;Entry: ; SI = start of procedure list ; DI = end of procedure list ; ;Exit: ; ;Uses: ; ;Exceptions: ; ;******************************************************************************* if sizeC farinitterm: ; large code farinitterm = initterm endif initterm: cmp si,di ; are we done? jae itdone ; yes - no more if sizeC sub di,4 mov ax,[di] or ax,[di+2] jz initterm ; skip null procedures call dword ptr [di] else dec di dec di mov cx,[di] jcxz initterm ; skip null procedures call cx endif jmp initterm ; keep looping itdone: ret page ife sizeC ; S/C models only ;*** ;farinitterm - do a set of far initializers or terminators ; ;Purpose: ; The initializors and terminators may be written in C ; so we are assuming C conventions (DS=SS, CLD, SI and DI preserved) ; We go through them in reverse order for onexit. ; ;Entry: ; SI = start of procedure list ; DI = end of procedure list ; ;Exit: ; ;Uses: ; ;Exceptions: ; ;******************************************************************************* farinitterm: cmp si,di ; are we done? jae faritdone ; yes - no more sub di,4 mov ax,[di] or ax,[di+2] jz farinitterm ; skip null procedures call dword ptr [di] jmp farinitterm ; keep looping faritdone: ret endif ;sizeC sEnd end