1 ;; rdtmain - main part of test program for RDX execution. 2 ;; returns true (0) if its parameter equals the phrase "hello" 3 ;; "hello" is stored in the library part, to complicate the 4 ;; linkage. 5 6 ;; assemble and link with the following commands: 7 ;; nasm -f rdf rdtmain.asm 8 ;; nasm -f rdf rdtlib.asm 9 ;; ldrdf rdtmain.rdf rdtlib.rdf -o rdxtest.rdx 10 11 ;; run with 'rdx rdxtest.rdx [parameters]' on a Linux (or possibly 12 ;; other 32 bit OS) systems (x86 architectures only!) 13 ;; try using '&& echo Yes' afterwards to find out when it returns 0. 14 15 [EXTERN _strcmp] ; strcmp is an imported function 16 [EXTERN _message] ; imported data 17 [SECTION .text] 18 [BITS 32] 19 20 ;; main(int argc,char **argv) 21 [GLOBAL _main] 22 _main: 23 push ebp 24 mov ebp,esp 25 26 ;; ebp+8 = argc, ebp+12 = argv 27 28 cmp dword [ebp+8],2 29 jb error ; cause error if < 1 parameters 30 31 mov eax, [ebp+12] ; eax = argv 32 33 mov ebx, [eax+4] ; ebx = argv[1] 34 mov ecx, _message ; ecx = "hello" 35 36 push ecx 37 push ebx 38 call _strcmp ; compare strings 39 add esp,8 ; caller clears stack 40 41 pop ebp 42 ret ; return return value of _strcmp 43 44 error: 45 mov eax,2 ; return 2 on error 46 pop ebp 47 ret 48
