#include <EXTERN.h>
#include <perl.h>

static PerlInterpreter *my_perl = NULL ;

void load_perl(){
	char *embedding[] = { "", "-e", "0" };

	if (my_perl == NULL){
		my_perl = perl_alloc();
		perl_construct( my_perl );

		perl_parse(my_perl, NULL, 3, embedding, NULL);
		perl_run(my_perl);
	}
}


char *eval_perl(char *user_code, char **error){
	char *code = (char *)calloc(strlen(user_code) + 512, sizeof(char)) ;
	SV *ret = NULL ;
	SV *err = NULL ;

	strcat(code, user_code) ;

 	ret = eval_pv(user_code, FALSE) ;
	free(code) ;
	err = get_sv("@", TRUE) ;
	if (SvTRUE(err)){
		*error = SvPV_nolen(err) ;
		return NULL ;
	}
	
	return SvPV_nolen(ret) ;
}


void unload_perl(){
	if (my_perl != NULL){
		perl_destruct(my_perl);
		perl_free(my_perl);
		my_perl = NULL ;
	}
}


main (int argc, char **argv){
	char code[1024] ;
	char *error = NULL ;
	char *ret = NULL ;

	sprintf(code, "%s", "die('!!') ;") ;

	load_perl() ;
	ret = eval_perl(code, &error) ;
	if (error != NULL){
		printf("ERROR: %s\n", error) ;
	}
	else{
		printf("SUCCESS: %s\n", ret) ;
	}
	unload_perl() ;
}