Re^2: Extending perl with C dynamic library.

[Martin90]

syphilis, thanks that helped and .so are smaller ;)

spx2 thanks for good resource !

Unfortunately I encountered another problem, this time when I try to add perl compiler to C.

#!/usr/bin/perl

use strict; 
use warnings;
use Config;
use Inline C => Config => BUILD_NOISY => 1, CCFLAGS => $Config{ccflags
+}." -DDEBUG=1";
use Inline C => <<'END_C',  NAME => 'Example', CLEAN_AFTER_BUILD =>0;


static PerlInterpreter *my_perl;

int main(int argc, char **argv) {

char* command_line[] = {"", "-e", "print \"Hello from C!\\n\";"};
my_perl = perl_alloc();
perl_construct(my_perl);
perl_parse(my_perl, NULL, 3, command_line, (char **)NULL);
perl_run(my_perl);
perl_destruct(my_perl);
perl_free(my_perl);
return 0;
}

int add( int a, int b ) {
    int result;
    result = a + b;
    return result;
}

int hello() {

 printf("Hello World\n");
 
 }


END_C


sub message {

print "Everything went well"

}

&message;

On windows this code fail:

"Dmake error code 129, while making \/patch_here/Example.dll" "A problem was encountered while attepting to compile and install your inline c code. The command that failed was dmake."

On Linux (CentOS 6) program compile successfully but problem appears in next step:

cc -o Example.o -c Example.c `perl -MExtUtils::Embed -e ccopts`

returns:

"Example.xs:4:20: error: INLINE.h: No such file or directory Example.c: In function âXS_main_mainâ: Example.c:55: warning: initialization makes pointer from integer without a cast"

Because Inline produce their own .o file I try to compile their .o file, again with no success:

cc -o Example Example.o `perl -MExtUtils::Embed -e ldopts`

return:

"Example.o: In function `XS_main_main': /home/admin/Embed/_Inline/build/Example/Example.c:55: undefined reference to `XS_unpack_charPtrPtr' collect2: ld returned 1 exit status"

I have no idea what is wrong here, looking for your help again monks ;)

Also, it is possible to implement full perl subroutine code to C code or just add pointer that refer to perl subroutine somewhere else ?

[BrowserUk]

You are trying to create a dll with a main entrypoint. No wonder it fails.

[Martin90]

Ok after hours of testing I resolved most of the problems. My main focus was to implment some necessary code into C but I can't do this even with the simplest code from documentation.

Here is an example:

#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"
#include <stdio.h>
#include "ppport.h"

   
static PerlInterpreter *my_perl;

int main(int argc, char **argv, char **env) {
SV *cvrv = eval_pv("sub { print 'You will not find me cluttering any n
+amespace!' }", TRUE);
char *args[] = { NULL };
PERL_SYS_INIT3(&argc,&argv,&env);
my_perl = perl_alloc();
perl_construct(my_perl);
perl_parse(my_perl, NULL, argc, argv, NULL);
PL_exit_flags |= PERL_EXIT_DESTRUCT_END;

/*** skipping perl_run() ***/

 call_sv(cvrv, G_VOID|G_NOARGS);

perl_destruct(my_perl);
perl_free(my_perl);
PERL_SYS_TERM();
}

MODULE = Example        PACKAGE = Example

NOTE: I back to XS and "make" since Inline has problems with compile this code. With make I compile this code fine to Example.c then with

cc -o interp Example.c `perl -MExtUtils::Embed -e ccopts -e ldopts`

produce executable file "interp". Up to this point everything went ok. The problem occur when i try tu run "interp":

% ./interp

returns :

Segmentation fault.

I think problem is in line: SV *cvrv = eval_pv("sub { print 'You will not find me cluttering any namespace!' }", TRUE);"

Documentation corresponding with this code:

http://perldoc.perl.org/perlcall.html#Creating-and-Calling-an-Anonymous-Subroutine-in-C

Do you know what is wrong ?

Thanks ;)

[syphilis]

Do you know what is wrong ?

You appear to be trying to embed perl into XS. I don't know of anyone ever having tried that, and I don't know why anyone *would* try that.
AFAIK, you only ever embed perl into a *C* program - and you do that only when you want to be able to run perl code in that C program.
If you want to run perl code from XS, you just do a callback to that perl code. Here is a simple Inline::C example based on an example in the perldoc perlcall documentation:

use strict;
use warnings;

use Inline C => Config =>
    USING => 'ParseRegExp',
    BUILD_NOISY => 1;

use Inline C => <<'EOC';

void c_foo(void) {
 dSP;

 PUSHMARK(SP);
 call_pv("perl_foo", G_DISCARD|G_NOARGS);
}

EOC

c_foo();

sub perl_foo {
            print "PID is $$\n";
}

I see you've found that perlcall documentation. Note that it contains no attempts to embed a perl interpreter into the code.

(In case you're unaware of it, Inline::C and XS are essentially the same - it's just that Inline::C writes your XS file for you, then compiles the XS code and runs the script.)

Cheers,
Rob

[BrowserUk]

Do you know what is wrong ?

Yes. Basically, you have no idea what you are doing.

You are still trying to compile a main() function into a dll.

Dlls contain and export entrypoints that *must* be dynamically linked to and called from an executable (with a main()).

You can't use Inline C to build main programs.

[syphilis]

On windows this code fail

On Windows, if (in your code) I replace int main(int argc, char **argv) { with int main(void) { then everything goes fine.
At least, I get output of Everything went well.

Does that help ? (I'm a bit lost as regards where this is heading.)

Cheers,
Rob