#include <stdio.h>
#include <stdlib.h>
#include <dlfcn.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/types.h>
#include <semaphore.h>
#include <string.h>

typedef struct {
    sem_t request_ready;  // начальное значение 0
    sem_t response_ready; // начальное значение 0
    char func_name[20];
    double value;
    double result;
} shared_data_t;

typedef double (*function)(double);


int main(int argc, char** argv) {
    void* lib = dlopen(argv[1], RTLD_LAZY);

    int shrd = shm_open("/pva_shrd", O_CREAT | O_RDWR, 0777);
    ftruncate(shrd, sizeof(shared_data_t));
    void* mmap_ptr = mmap(NULL, sizeof(shared_data_t), PROT_READ | PROT_WRITE, MAP_SHARED, shrd, 0);

    shared_data_t* task_ptr;
    task_ptr = mmap_ptr;
    sem_init(&task_ptr->request_ready, 1, 0);
    sem_init(&task_ptr->response_ready, 1, 0);

    printf("/pva_shrd\n");
    fflush(stdout);

    char func_name[20];
    int i = 0;
    while (1) {
        sem_wait(&task_ptr->request_ready);
        sscanf(task_ptr->func_name, "%s", func_name);
        if (strlen(task_ptr->func_name) == 0) {
            break;
        }
        function foo = dlsym(lib, task_ptr->func_name);
        task_ptr->result = foo(task_ptr->value);
        sem_post(&task_ptr->response_ready);
    }

    munmap(mmap_ptr, sizeof(shared_data_t));
    shm_unlink("/pva_shrd");

    dlclose(lib);
}