Category : BASIC Source Code
Archive   : MSGBLAST.ZIP
Filename : LIBENTRY.ASM

PAGE,132
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;
; LIBENTRY.ASM
;
; Windows dynamic link library entry routine
;
; This module generates a code segment called INIT_TEXT.
; It initializes the local heap if one exists and then calls
; the C routine LibMain() which should have the form:
; BOOL FAR PASCAL LibMain(HANDLE hInstance,
; WORD wDataSeg,
; WORD cbHeap,
; LPSTR lpszCmdLine);
;
; The result of the call to LibMain is returned to Windows.
; The C routine should return TRUE if it completes initialization
; successfully, FALSE if some error occurs.
;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

include cmacros.inc

externFP ; the C routine to be called

createSeg INIT_TEXT, INIT_TEXT, BYTE, PUBLIC, CODE
sBegin INIT_TEXT
assumes CS,INIT_TEXT

?PLM=0 ; 'C'naming
externA <_acrtused> ; ensures that Win DLL startup code is linked

?PLM=1 ; 'PASCAL' naming
externFP ; Windows heap init routine

cProc LibEntry, ; entry point into DLL

cBegin
push di ; handle of the module instance
push ds ; library data segment
push cx ; heap size
push es ; command line segment
push si ; command line offset

; if we have some heap then initialize it
jcxz callc ; jump if no heap specified

; call the Windows function LocalInit() to set up the heap
; LocalInit((LPSTR)start, WORD cbHeap);

xor ax,ax
cCall LocalInit
or ax,ax ; did it do it ok ?
jz error ; quit if it failed

; invoke the C routine to do any special initialization

callc:
call LibMain ; invoke the 'C' routine (result in AX)
jmp short exit ; LibMain is responsible for stack clean up

error:
pop si ; clean up stack on a LocalInit error
pop es
pop cx
pop ds
pop di

exit:

cEnd

sEnd INIT_TEXT

end LibEntry