executor_test.c

Go to the documentation of this file.

/*
 * Contains rough code for executor.c and tests functions written in executor.c
 */
#include <dlfcn.h>
#include <stdio.h>
#include <stdlib.h>
#include <ffi.h>

int main(int argc, char* argv) {

    void *lib_handle;
    double (*pow)(double, double);
    const char *dlsym_error;

    char *library_file = "/usr/lib/libm.dylib";
    char *routine_name = "pow";
    void (*routine_handle);

    // load the library libm
    lib_handle = dlopen(library_file, RTLD_LAZY);

    // check we could open the library
    if(!lib_handle) {
        printf("Cannot open library: %s\n", dlerror());
        return 1;
    } else {
        printf("Library opened: %s\n", library_file);
    }

        //reset errors
    dlerror();

    routine_handle = dlsym(lib_handle, routine_name);

    dlsym_error = dlerror();

    if(dlsym_error) {
        printf("Cannot load symbol: 'pow': %s\n", dlsym_error);
        dlclose(lib_handle);
        return 1;
    } else {
        printf("Symbol loaded: %s\n", routine_name);
    }


    //printf("foo: %.2f\n", (double) routine_handle(4.0, 3.0));
    {
        ffi_cif cif;
        ffi_type **args;
        int n_args;
        void **values;
        double *rc;
        int i;
        double a, b;

        args = malloc(n_args*sizeof(ffi_type*));
        values = malloc(n_args*sizeof(void*));
        rc = malloc(sizeof(double));

        if(!args || !values || !rc) {
            printf("Could not allocate memory for ffi\n");
            return 1;
        } else {
            printf("ffi memory allocated\n");
        }

        for(i=0; i<n_args; i++) {
            args[i] = &ffi_type_double;

        }

        values[0] = &a;
        values[1] = &b;

        if(ffi_prep_cif(&cif, FFI_DEFAULT_ABI, n_args, &ffi_type_double, args) == FFI_OK) {

            ffi_call(&cif, routine_name, rc, values);

            printf("%d\n", (double)*rc);
        }


        for(i=0;i<n_args;i++) {
            free(values[i]);
        }
    }
    dlclose(lib_handle);
    return 0;
}