Get default selinux user context

st.c

// gcc -lselinux st.c -o st.bin
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <selinux/selinux.h>
#include <selinux/get_context_list.h>

int main(){
  security_context_t *contextlist = NULL;
  int rc = -1;
  int count = 0;
  char *linuxuser = NULL;
  char *selinuxuser = NULL;
  char *level = NULL;
  char *newcon = NULL;
  // get current user from env USER
  linuxuser = getenv("USER");
  printf("Got: Linux user name: %s\n", linuxuser);
  count = ++count;
  // get selinux user by linux user name
  // int getseuserbyname(const char *linuxuser, char **selinuxuser, char **level);
  rc = getseuserbyname(linuxuser, &selinuxuser, &level);
  if (rc != 0)
    goto exit;
  printf("Got: SELinux user: %s\n", selinuxuser);
  count = ++count;
  printf("Got: SELinux level: %s\n", level);
  count = ++count;
  // Get default SELinux context for the curerent user
  // or the user specified in $USER env
  // int get_default_context(const char *user, char *fromcon, char **newcon);
  // fromcon = NULL -> current context should be used
  rc = get_default_context(selinuxuser, NULL, &newcon);
  if (rc != 0)
    goto exit;
  printf("Got: default context for the SELinux user: %s\n", newcon);
  count = ++count;

exit:
  // TODO: free memory (?)
  printf("Number of executed tests: %d out of 4\n", count);
  printf("st finished, exit code is: %d\n", rc);
  return rc;
}