| [9] | 1 | ! This is the Modula-2 run-time start-off routine. It's job is to take the
|
|---|
| 2 | ! arguments as put on the stack by EXEC, and to parse them and set them up the
|
|---|
| 3 | ! way _m_a_i_n expects them.
|
|---|
| 4 |
|
|---|
| 5 | .extern __m_a_i_n, _exit, m2rtso, hol0, __penvp
|
|---|
| 6 | .extern begtext, begdata, begbss, endtext, enddata, endbss
|
|---|
| 7 | .text
|
|---|
| 8 | begtext:
|
|---|
| 9 | m2rtso:
|
|---|
| 10 | xor bp, bp ! clear for backtrace of core files
|
|---|
| 11 | mov bx, sp
|
|---|
| 12 | mov ax, (bx) ! argc
|
|---|
| 13 | lea dx, 2(bx) ! argv
|
|---|
| 14 | lea cx, 4(bx)
|
|---|
| 15 | add cx, ax
|
|---|
| 16 | add cx, ax ! envp
|
|---|
| 17 |
|
|---|
| 18 | ! Test if environ is in the initialized data area and is set to our
|
|---|
| 19 | ! magic number. If so then it is not redefined by the user.
|
|---|
| 20 | mov bx, #_environ
|
|---|
| 21 | cmp bx, #__edata ! within initialized data?
|
|---|
| 22 | jae 0f
|
|---|
| 23 | testb bl, #1 ! aligned?
|
|---|
| 24 | jnz 0f
|
|---|
| 25 | cmp (bx), #0x5353 ! is it our environ?
|
|---|
| 26 | jne 0f
|
|---|
| 27 | mov __penviron, bx ! _penviron = &environ;
|
|---|
| 28 | 0: mov bx, __penviron
|
|---|
| 29 | mov (bx), cx ! *_penviron = envp;
|
|---|
| 30 |
|
|---|
| 31 | push cx ! push envp
|
|---|
| 32 | push dx ! push argv
|
|---|
| 33 | push ax ! push argc
|
|---|
| 34 |
|
|---|
| 35 | call __m_a_i_n ! run Modula-2 program
|
|---|
| 36 |
|
|---|
| 37 | push ax ! push exit status
|
|---|
| 38 | call __exit
|
|---|
| 39 |
|
|---|
| 40 | hlt ! force a trap if exit fails
|
|---|
| 41 |
|
|---|
| 42 | .data
|
|---|
| 43 | begdata:
|
|---|
| 44 | .data2 0 ! for sep I&D: *NULL == 0
|
|---|
| 45 | __penviron:
|
|---|
| 46 | .data2 __penvp ! Pointer to environ, or hidden pointer
|
|---|
| 47 |
|
|---|
| 48 | .bss
|
|---|
| 49 | begbss:
|
|---|
| 50 | .comm __penvp, 2 ! Hidden environment vector
|
|---|
