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/*
FUSE: Filesystem in Userspace
Copyright (C) 2001 Miklos Szeredi (mszeredi@inf.bme.hu)
This program can be distributed under the terms of the GNU GPL.
See the file COPYING.
*/
#include <fuse.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <signal.h>
#include <time.h>
#define UNUSED __attribute__((unused))
static char *unmount_cmd;
static int null_getattr(const char *path, struct stat *stbuf)
{
if(strcmp(path, "/") != 0)
return -ENOENT;
stbuf->st_mode = S_IFREG | 0644;
stbuf->st_nlink = 1;
stbuf->st_uid = getuid();
stbuf->st_gid = getgid();
stbuf->st_size = (1 << 30); /* 1G */
stbuf->st_blocks = 0;
stbuf->st_atime = stbuf->st_mtime = stbuf->st_ctime = time(NULL);
return 0;
}
static int null_truncate(const char *path, off_t UNUSED(size))
{
if(strcmp(path, "/") != 0)
return -ENOENT;
return 0;
}
static int null_open(const char *path, int UNUSED(flags))
{
if(strcmp(path, "/") != 0)
return -ENOENT;
return 0;
}
static int null_read(const char *path, char *UNUSED(buf), size_t size,
off_t UNUSED(offset))
{
if(strcmp(path, "/") != 0)
return -ENOENT;
return size;
}
static int null_write(const char *path, const char *UNUSED(buf), size_t size,
off_t UNUSED(offset))
{
if(strcmp(path, "/") != 0)
return -ENOENT;
return size;
}
static struct fuse_operations null_oper = {
getattr: null_getattr,
readlink: NULL,
getdir: NULL,
mknod: NULL,
mkdir: NULL,
symlink: NULL,
unlink: NULL,
rmdir: NULL,
rename: NULL,
link: NULL,
chmod: NULL,
chown: NULL,
truncate: null_truncate,
utime: NULL,
open: null_open,
read: null_read,
write: null_write,
};
static void exit_handler()
{
close(0);
system(unmount_cmd);
exit(0);
}
static void set_signal_handlers()
{
struct sigaction sa;
sa.sa_handler = exit_handler;
sigemptyset(&(sa.sa_mask));
sa.sa_flags = 0;
if (sigaction(SIGHUP, &sa, NULL) == -1 ||
sigaction(SIGINT, &sa, NULL) == -1 ||
sigaction(SIGTERM, &sa, NULL) == -1) {
perror("Cannot set exit signal handlers");
exit(1);
}
sa.sa_handler = SIG_IGN;
if(sigaction(SIGPIPE, &sa, NULL) == -1) {
perror("Cannot set ignored signals");
exit(1);
}
}
int main(int argc, char *argv[])
{
int argctr;
int flags;
int multithreaded;
struct fuse *fuse;
if(argc < 2) {
fprintf(stderr,
"usage: %s unmount_cmd [options] \n"
"Options:\n"
" -d enable debug output\n"
" -s disable multithreaded operation\n",
argv[0]);
exit(1);
}
argctr = 1;
unmount_cmd = argv[argctr++];
set_signal_handlers();
flags = 0;
multithreaded = 1;
for(; argctr < argc && argv[argctr][0] == '-'; argctr ++) {
switch(argv[argctr][1]) {
case 'd':
flags |= FUSE_DEBUG;
break;
case 's':
multithreaded = 0;
break;
default:
fprintf(stderr, "invalid option: %s\n", argv[argctr]);
exit(1);
}
}
if(argctr != argc) {
fprintf(stderr, "missing or surplus argument\n");
exit(1);
}
fuse = fuse_new(0, flags);
fuse_set_operations(fuse, &null_oper);
if(multithreaded)
fuse_loop_mt(fuse);
else
fuse_loop(fuse);
return 0;
}
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