null_fs 0.0.1.1

/* > /dev/null 2>&1
gcc $0 -D_FILE_OFFSET_BITS=64 -DFUSE_USE_VERSION=25 -lfuse -o null_fs "$@"
exit
*/
#include <fuse.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>

static int dev_null_fd;
static char *troll;

static int null_getattr(const char *path, struct stat *stbuf)
{
    memset(stbuf, 0, sizeof(struct stat));
    if(strcmp(path, "/") == 0)
    {
        stbuf->st_mode = S_IFDIR | 0777;
        stbuf->st_nlink = 2;
        return 0;
    }
    if(strcmp(path, troll) == 0)
    {
        stbuf->st_mode = S_IFREG | 0777;
        stbuf->st_nlink = 1;
        return 0;
    }
    return -ENOENT;
}

static int null_readdir(const char *path, void *buf, fuse_fill_dir_t filler,
                        off_t offset, struct fuse_file_info *fi)
{
    if(strcmp(path, "/") != 0)
    {
        return -ENOENT;
    }
    filler(buf, ".", NULL, 0);
    filler(buf, "..", NULL, 0);
    return 0;
}

static int null_open(const char *path, struct fuse_file_info *fi)
{
    return 0;
}

static int null_read(const char *path, char *buf, size_t size, off_t offset,
                     struct fuse_file_info *fi)
{
    return read(dev_null_fd, buf, size);
}

static int null_write(const char *path, const char *buf, size_t size, off_t offset,
                      struct fuse_file_info *fi)
{
    return size;
}

static int null_create(const char *path, mode_t mode, struct fuse_file_info *fi)
{
    free(troll);
    troll = strdup(path);
    return 0;
}

static struct fuse_operations null_oper = {
    .getattr = null_getattr,
    .readdir = null_readdir,
    .open = null_open,
    .read = null_read,
    .write = null_write,
    .create = null_create
};

int main(int argc, char *argv[])
{
    troll = strdup("");
    dev_null_fd = open("/dev/null",O_RDWR);
    return fuse_main(argc, argv, &null_oper);
}