Machine code: Difference between revisions

=={{header|Raku}}==

I don't know how to translate this C line <lang C>c = ((int (*) (int, int))buf)(a, b);</lang> so cannot solve the task with an idiomatic solution. I have also tried with Go's approach by adding a helper program but it also doesn't work out. Nonetheless I just present the attempt here so perhaps someone can fix that in 10 seconds.

<lang raku>use NativeCall;

constant PROT_READ = 0x1; #

constant PROT_WRITE = 0x2; #

constant PROT_EXEC = 0x4; # from local /usr/include/bits/mman.h

constant MAP_PRIVATE = 0x02; #

constant MAP_ANON = 0x20; #

sub mmap(Pointer $addr, size_t $length, int32 $prot, int32 $flags,

int32 $fd, size_t $offset --> Pointer) is native { * };

sub malloc(size_t $size --> Pointer) is native {*}

sub memcpy(Pointer $dest, Pointer $src, size_t $size --> Pointer) is native {*}

sub munmap(Pointer $addr, size_t $length) is native { * };

sub test (uint8 $a, uint8 $b) {

my $code = CArray[uint8].new(

0x90, 0x90, 0x6A, 0xC, 0xB8, 0x7, 0x0, 0x0, 0x0, 0x48, 0xC1, 0xE0, 0x20,

0x50, 0x8B, 0x44, 0x24, 0x4, 0x3, 0x44, 0x24, 0x8, 0x4C, 0x89, 0xE3, 0x89,

0xC3, 0x48, 0xC1, 0xE3, 0x4, 0x80, 0xCB, 0x2, 0x48, 0x83, 0xC4, 0x10, 0xC3

);

my $buf =

mmap(Pointer, nativesizeof($code), PROT_READ +| PROT_WRITE +| PROT_EXEC,

MAP_PRIVATE +| MAP_ANON, -1, 0);

memcpy($buf, nativecast(Pointer,$code), nativesizeof($code));

my $c; # = ((int (*) (int, int))buf)(a, b);

munmap($buf, nativesizeof($code));

return $c = "Incomplete Attempt";

}

say test 7, 12;</lang>

In the mean time, here is a less desirable approach by writing a wrapper for the C entry, with the 64 bit instructions from PicoLisp ..

{{trans|C}} test.c

<lang C>#include <stdio.h>

#include <stdlib.h>

#include <sys/mman.h>

#include <string.h>

int test (int a, int b)

{

char code[] = {

0x90, 0x90, 0x6A, 0xC, 0xB8, 0x7, 0x0, 0x0, 0x0, 0x48, 0xC1, 0xE0, 0x20,

0x50, 0x8B, 0x44, 0x24, 0x4, 0x3, 0x44, 0x24, 0x8, 0x4C, 0x89, 0xE3, 0x89,

0xC3, 0x48, 0xC1, 0xE3, 0x4, 0x80, 0xCB, 0x2, 0x48, 0x83, 0xC4, 0x10, 0xC3

};

void *buf;

int c;

/* copy code to executable buffer */

buf = mmap (0,sizeof(code),PROT_READ|PROT_WRITE|PROT_EXEC,

MAP_PRIVATE|MAP_ANON,-1,0);

memcpy (buf, code, sizeof(code));

/* run code */

c = ((int (*) (int, int))buf)(a, b);

/* free buffer */

munmap (buf, sizeof(code));

return c;

}</lang>

mcode.raku

<lang raku>#!/usr/bin/env raku

# 20200501 Raku programming solution

use NativeCall;

constant LIBTEST = '/home/user/LibTest.so';

sub test(uint8 $a, uint8 $b) returns uint8 is native(LIBTEST) { * };

say test 7, 12;

</lang>

{{out}}<pre>gcc -Wall -fPIC -shared -o LibTest.so test.c

file LibTest.so

LibTest.so: ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), dynamically linked, BuildID[sha1]=90d2695df9a56b88a57144147fb9288ac07b172f, not stripped

./mcode.raku

19</pre>