Luna/libs/libc/src/init.cpp

#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

static void terminate_libc()
{
    fclose(stdout);
    fclose(stderr);
}

static void check_for_file(int fd, FILE** target_stream, const char* path, const char* mode)
{
    if (lseek(fd, 0, SEEK_CUR) < 0)
    {
        if (errno == EBADF) *target_stream = fopen(path, mode);
        else
            exit(errno);
        if (!*target_stream) exit(errno);
        errno = 0;
    }
    else { *target_stream = fdopen(fd, mode); }
}

extern "C" void initialize_libc()
{
    check_for_file(STDOUT_FILENO, &stdout, "/dev/console", "rw");
    check_for_file(STDERR_FILENO, &stderr, "/dev/console", "rw");
    atexit(terminate_libc);
}