50 lines
1.2 KiB
ArmAsm
50 lines
1.2 KiB
ArmAsm
! This is the Modula-2 run-time start-off routine. It's job is to take the
|
|
! arguments as put on the stack by EXEC, and to parse them and set them up the
|
|
! way _m_a_i_n expects them.
|
|
|
|
.extern __m_a_i_n, _exit, m2rtso, hol0, __penvp
|
|
.extern begtext, begdata, begbss, endtext, enddata, endbss
|
|
.text
|
|
begtext:
|
|
m2rtso:
|
|
xor bp, bp ! clear for backtrace of core files
|
|
mov bx, sp
|
|
mov ax, (bx) ! argc
|
|
lea dx, 2(bx) ! argv
|
|
lea cx, 4(bx)
|
|
add cx, ax
|
|
add cx, ax ! envp
|
|
|
|
! Test if environ is in the initialized data area and is set to our
|
|
! magic number. If so then it is not redefined by the user.
|
|
mov bx, #_environ
|
|
cmp bx, #__edata ! within initialized data?
|
|
jae 0f
|
|
testb bl, #1 ! aligned?
|
|
jnz 0f
|
|
cmp (bx), #0x5353 ! is it our environ?
|
|
jne 0f
|
|
mov __penviron, bx ! _penviron = &environ;
|
|
0: mov bx, __penviron
|
|
mov (bx), cx ! *_penviron = envp;
|
|
|
|
push cx ! push envp
|
|
push dx ! push argv
|
|
push ax ! push argc
|
|
|
|
call __m_a_i_n ! run Modula-2 program
|
|
|
|
push ax ! push exit status
|
|
call __exit
|
|
|
|
hlt ! force a trap if exit fails
|
|
|
|
.data
|
|
begdata:
|
|
.data2 0 ! for sep I&D: *NULL == 0
|
|
__penviron:
|
|
.data2 __penvp ! Pointer to environ, or hidden pointer
|
|
|
|
.bss
|
|
begbss:
|
|
.comm __penvp, 2 ! Hidden environment vector
|