; ; EXIT.A (Alfred Faust , 2001) ; adapted from C.A ; ; to compile Tools&Accessories for Bars&Pipes ; Mainly for use the __exit and __MemList functions while linking ; without to have the _main (Tools&Accessories are not ; selfstarting programs). ; ; Use it in conjunction of x.o at the last position in the link ; chain. ; ; Example: ; ; dlink mmc.o exit.o cs.lib amiga3.1s.lib x.o -o MMC.paccess ; ; (C)Copyright 1990-1992, Matthew Dillon, All Rights Reserved ; ; Amiga startup code for resident and non-resident DCC programs. ; ; DLINK supplied variables: ; ; * __BSS_LEN : # long words of BSS (occurs after DATA) ; * __DATA_LEN : # long words of initialized data to copy ; (if resident) ; * __DATA_BAS : Base of data (read only if resident) ; * __RESIDENT : Is this code residentable? If this variable ; is set then there are no absolute data/bss ; references except __DATA_BAS and there is ; NO BSS MEMORY ALLOCATED AFTER THE DATA ; SECTION. ; ; If this variable is not set then absolute ; references refer to the same storage as ; A4 relative accesses and uninitialized ; BSS space exists just after the data section. ; ; Note that in the large-data model + fragmented ; sections, there are usually real BSS hunks ; floating about that have been zerod by ; LoadSeg() (in this case __BSS_LEN could be 0) ; ; COMPILER: ; ; * If -r option specified when compiling then the compiler ; will generate autoinit code to handle data initialization ; that would otherwise require a reloc32 hunk. ; ; * If -r or -md specified compiler references all data items ; using A4-Relative addressing. ; ; C LIB CODE: ; ; * Resident: Allocate (__DATA_LEN+__BSS_LEN)*4 ; Not Resident: Zero out preallocated BSS. ; ; * Generate A4 ref ptr to bss base + 32766 (uses Aztec's ; conventions). ; ; * All library code uses the SMALL-DATA with alternate ; BSS and DATA section names (based in this source ; file) so the linker puts library related data/bss ; first. BUT, BSS always comes after DATA unless ; you -frag the link (can't resident a frag'd link), ; so if there is more than 64KBytes of *initialized* ; data you must -frag the link. ; section text,code xref __RESIDENT ; (dlink), executable is residentable xref __BSS_LEN ; (dlink), length of BSS xref __DATA_BAS ; (dlink), base of initialized data xref __DATA_LEN ; (dlink), length of data xref _LVOSetSignal xref _LVOAllocMem xref _LVOFreeMem xref _LVOForbid xref _LVOReplyMsg xdef __exit ; we are _exit() start: ;;;;;;;;;;;;;;;;movem.l D2-D7/A2-A6,-(sp) ;Not needed! move.l 4.W,A6 ; Exec base move.l sp,A2 move.l A0,-(sp) ; save arg for _main() call move.l D0,-(sp) ; save arglen for _main() call ; If we are flagged resident then there is NO BSS ALLOCATED ; If we are not flagged resident then BSS IS ALLOCATED AFTER ; DATA, BUT NOT CLEARED. move.w #__RESIDENT,D0 beq snotres ; Allocate BSS+DATA space and then copy static data. move.l #__BSS_LEN,D0 add.l #__DATA_LEN,D0 asl.l #2,D0 ; x4 addq.l #8,D0 ; MemList header extra move.l D0,D5 ; D5 = #bytes moveq.l #0,D1 ; Any memory ok jsr _LVOAllocMem(A6) tst.l D0 bne alok move.l A2,sp moveq.l #-1,D0 bra exfail alok move.l D0,A0 clr.l (A0)+ ; MemList entry next ptr move.l D5,(A0)+ ; MemList entry #bytes lea 32766(A0),A4 ; SET A4 lea -8(A0),A3 ; A3 = MemList entry base ; can't copy to MemList(A4) yet ; Copy data to allocated copy ; A0 = dst lea __DATA_BAS,A1 ; A1 = src move.l #__DATA_LEN,D0 ; D0 = long words bra bssent bsslop move.l (A1)+,(A0)+ bssent dbf D0,bsslop sub.l #$10000,D0 bcc bsslop bra clrbss ; Not resident, BSS space has been allocated for us ; beyond the specified data, just load the base ptr snotres lea __DATA_BAS,A4 lea 32766(A4),A4 sub.l A3,A3 clrbss ; CLEAR BSS &-32766(A4) + __DATA_LEN*4 lea -32766(A4),A0 move.l #__DATA_LEN,D0 asl.l #2,D0 add.l D0,A0 move.l #__BSS_LEN,D0 ; longwords of bss moveq.l #0,D1 bra clrent clrlop move.l D1,(A0)+ clrent dbf D0,clrlop sub.l #$10000,D0 bcc clrlop move.l A3,___MemList(A4) ; memlist entry (if resident) move.l A2,__ExitSP(A4) ; sp to restore moveq.l #0,D0 ; new signals move.l #$1000,D1 ; signal mask jsr _LVOSetSignal(A6) ; clear ^C ; Return value of 0 indicates succcess. Flags ; have been set. ; ; Note that if the standard _main entry point is used, ; the very first autoinit0 code will check for and ; retrieve the workbench message. jsr __AutoInit0 ; A6 has SYSBase bne xfail pea 1.W ; autoconfig loader jsr __AutoConfig ; note, rt pulls stack addq.l #4,sp jsr __AutoInit1 ; A6 has SYSBase bne xfail ; fall through to low level exit... this avoids referencing ; exit() if the user overides _main(). xfail clr.l -(sp) clr.l -(sp) ; _EXIT() ; ; since entry uses malloc we must free any incidental memory ; at __exit instead of _exit. ; ; ReplyMsg(_WBMsg) just before returning __exit: pea -1.W jsr __AutoConfig ; note, rt pulls stack addq.l #4,sp move.l _SysBase(A4),A6 jsr __AutoExit1 ; A6 has SysBase jsr __AutoExit0 ; A6 has SysBase move.l 4(sp),D0 move.l __ExitSP(A4),A7 ; get sp... because we might free ; the space taken by the variable! move.l D0,-(sp) ; save exit code on original stack move.l ___MemList(A4),D0 ; free memory beq ex20 ex10 move.l D0,A2 move.l (A2),A3 ; next... move.l 4(A2),D0 ; bytes move.l A2,A1 ; ptr jsr _LVOFreeMem(A6) move.l A3,D0 ; next... bne ex10 ex20 move.l (sp)+,D0 ; get exit code ;move.l 4(sp),D0 ; get exit code ;move.l A5,sp ; restore sp tst.l D6 ; reply to workbench msg if it beq ex30 ; exists jsr _LVOForbid(A6) ; forbid through exit move.l D6,A1 jsr _LVOReplyMsg(A6) ex30 ; FINIS, poof. exfail ;;;;;;;;;;;;;;;;movem.l (sp)+,D2-D7/A2-A6 rts ; Base of autoinit section section autoinit0,code __AutoInit0: section autoinit1,code __AutoInit1: section autoexit0,code __AutoExit0: section autoexit1,code __AutoExit1: section autoconfig,code __AutoConfig: ; All library C code is compiled with the -S option ; which uses 'libdata' and 'libbss' section names, ; forcing library data to come before program data ; and library bss to come before program bss (because ; library data/bss sections are declared here first ; and sections of like name are coagulated). ; ; All items are declared as data instead of bss, even ; through they could be bss, to support a >64K of ; initialized data with the small-data libraries. section libdata,data xdef ___MemList ; Used by malloc/free xdef __ExitSP _SysBase ds.l 1 ; Pointer to exec.library __ExitSP ds.l 1 ; Stack pointer for use in exit __WBMsg ds.l 1 ; Workbench startup message ___MemList ds.l 1 ; List of allocated memory section libbss,bss _Reserved ds.l 0 ; Force section to exist (dummy) END