#include "entropy.h"
#include "common.h"


int handle_event(void *ctx, void *data, size_t data_sz){
    struct random *s_random = (struct random*)data;
    pid_t pid = s_random->pid;
    char procname[PROCNAME_SIZE];
    char pathname[64];
    FILE *fd;
    memset(procname, 0, PROCNAME_SIZE);
    memset(pathname, 0, 64);

    // Get the proc name
 	snprintf(pathname, 64, "/proc/%d/stat", pid);
    if ((fd = fopen(pathname, "r")) == NULL){
		printf("Failed to open the file\n");
		return -1;
	}
    fscanf(fd, "%*d %s", procname);

    printf("proc: %s; pid: %d\n", procname, s_random->pid);

    fclose(fd);

    return 0;
}
int entropy(char **argv, int argc){
    const char *fileObj = "entropy_ebpf.o";
    struct bpf_object *obj;
    struct bpf_program *program;
    struct ring_buffer *rb;
    int err;
    int fd_map_data;
    int running = 1;

    // Load eBPF
    obj = bpf_object__open_file(fileObj, NULL);
    if (!obj){
        printf("Failed to open %s\n", fileObj);
        return -1;
    }

    err = bpf_object__load(obj);

    if (err){
        printf("Failed to load object\n");
        return -1;
    }

    //program = bpf_object__find_program_by_name(obj, "get_random");
    program = bpf_object__find_program_by_name(obj, "get_random_user");
    if (!program){
        printf("Failed to find the program\n");
        return -1;
    }

    fd_map_data = bpf_object__find_map_fd_by_name(obj, "data");
    if (!fd_map_data){
        printf("Failed to find the FD of the map\n");
        return -1;
    }

    bpf_program__attach(program);

    /* Start the ringbuffer */
    rb = ring_buffer__new(fd_map_data, handle_event, NULL, NULL);
    if (!rb){
        printf("Failed to create the ringbuf\n");
        bpf_object__close(obj);
        return -1;
    }

    while(running){
        err = ring_buffer__poll(rb, 100 /* timeout, ms */);
        if (err == -EINTR){
            printf("Failed to get the ringbuf\n");
            running = 0;
            break;
         }
    }

    ring_buffer__free(rb);
    bpf_object__close(obj);

    // Generate RSA keys and check the entropy available

}