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48 lines
1.1 KiB
NASM
48 lines
1.1 KiB
NASM
;; rdtmain - main part of test program for RDX execution.
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;; returns true (0) if its parameter equals the phrase "hello"
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;; "hello" is stored in the library part, to complicate the
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;; linkage.
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;; assemble and link with the following commands:
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;; nasm -f rdf rdtmain.asm
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;; nasm -f rdf rdtlib.asm
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;; ldrdf rdtmain.rdf rdtlib.rdf -o rdxtest.rdx
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;; run with 'rdx rdxtest.rdx [parameters]' on a Linux (or possibly
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;; other 32 bit OS) systems (x86 architectures only!)
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;; try using '&& echo Yes' afterwards to find out when it returns 0.
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[EXTERN _strcmp] ; strcmp is an imported function
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[EXTERN _message] ; imported data
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[SECTION .text]
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[BITS 32]
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;; main(int argc,char **argv)
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[GLOBAL _main]
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_main:
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push ebp
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mov ebp,esp
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;; ebp+8 = argc, ebp+12 = argv
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cmp dword [ebp+8],2
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jb error ; cause error if < 1 parameters
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mov eax, [ebp+12] ; eax = argv
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mov ebx, [eax+4] ; ebx = argv[1]
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mov ecx, _message ; ecx = "hello"
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push ecx
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push ebx
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call _strcmp ; compare strings
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add esp,8 ; caller clears stack
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pop ebp
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ret ; return return value of _strcmp
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error:
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mov eax,2 ; return 2 on error
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pop ebp
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ret
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