#define _GNU_SOURCE

#include <dlfcn.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>

char *getlogin(void) {
    return getenv("USER");
}

int getlogin_r(char *buf, size_t bufsize) {
    strncpy(buf, getlogin(), bufsize);
    return 0;
}

struct passwd *getpwuid(uid_t uid) {
    struct passwd *(*getpwuid)(uid_t) = dlsym(RTLD_NEXT, "getpwuid");
    if (getpwuid == NULL) {
        fprintf(stderr, "Unable to find the adress of the getpwuid function: %s\n", dlerror());
        return NULL;
    }
    struct passwd *pass = getpwuid(uid);
    char *name = getenv("USER");
    if (name == NULL) {
        fprintf(stderr, "Could not find the USER environment variable. Using the real username.\n");
        return pass;
    }
    pass->pw_name = name;
    return pass;
}