61 #define FUSE_USE_VERSION 31    63 #include <fuse_lowlevel.h>    76 #define NO_TIMEOUT 500000    78 #define MAX_STR_LEN 128    80 #define FILE_NAME "current_time"    81 static char file_contents[MAX_STR_LEN];
    82 static int lookup_cnt = 0;
    83 static size_t file_size;
    87 static int retrieve_status = 0;
    94 static struct options options = {
    99 #define OPTION(t, p)                           \   100     { t, offsetof(struct options, p), 1 }   101 static const struct fuse_opt option_spec[] = {
   102     OPTION(
"--no-notify", no_notify),
   103     OPTION(
"--update-interval=%d", update_interval),
   107 static int tfs_stat(
fuse_ino_t ino, 
struct stat *stbuf) {
   110         stbuf->st_mode = S_IFDIR | 0755;
   114     else if (ino == FILE_INO) {
   115         stbuf->st_mode = S_IFREG | 0444;
   117         stbuf->st_size = file_size;
   129     memset(&e, 0, 
sizeof(e));
   133     else if (strcmp(name, FILE_NAME) == 0) {
   139     e.attr_timeout = NO_TIMEOUT;
   140     e.entry_timeout = NO_TIMEOUT;
   141     if (tfs_stat(e.ino, &e.attr) != 0)
   154         lookup_cnt -= nlookup;
   166     memset(&stbuf, 0, 
sizeof(stbuf));
   167     if (tfs_stat(ino, &stbuf) != 0)
   178 static void dirbuf_add(
fuse_req_t req, 
struct dirbuf *b, 
const char *name,
   181     size_t oldsize = b->size;
   183     b->p = (
char *) realloc(b->p, b->size);
   184     memset(&stbuf, 0, 
sizeof(stbuf));
   190 #define min(x, y) ((x) < (y) ? (x) : (y))   192 static int reply_buf_limited(
fuse_req_t req, 
const char *buf, 
size_t bufsize,
   193                              off_t off, 
size_t maxsize) {
   196                               min(bufsize - off, maxsize));
   210         memset(&b, 0, 
sizeof(b));
   211         dirbuf_add(req, &b, FILE_NAME, FILE_INO);
   212         reply_buf_limited(req, b.p, b.size, off, size);
   226     else if ((fi->
flags & O_ACCMODE) != O_RDONLY)
   228     else if (ino == FILE_INO)
   232         fprintf(stderr, 
"Got open for non-existing inode!\n");
   241     assert(ino == FILE_INO);
   242     reply_buf_limited(req, file_contents, file_size, off, size);
   248     char buf[MAX_STR_LEN];
   252     assert(ino == FILE_INO);
   254     expected = (
char*) cookie;
   259     bufv.buf[0].size = MAX_STR_LEN;
   260     bufv.buf[0].mem = 
buf;
   261     bufv.buf[0].
flags = 0;
   265     assert(strncmp(buf, expected, ret) == 0);
   274     .getattr    = tfs_getattr,
   275     .readdir    = tfs_readdir,
   278     .forget     = tfs_forget,
   279     .retrieve_reply = tfs_retrieve_reply,
   282 static void update_fs(
void) {
   289     file_size = strftime(file_contents, MAX_STR_LEN,
   290                          "The current time is %H:%M:%S\n", now);
   291     assert(file_size != 0);
   294 static void* update_fs_loop(
void *data) {
   295     struct fuse_session *se = (
struct fuse_session*) data;
   301         if (!options.no_notify && lookup_cnt) {
   307             bufv.buf[0].size = file_size;
   308             bufv.buf[0].mem = file_contents;
   309             bufv.buf[0].flags = 0;
   314             if (-ret == ENODEV) {
   319                 fprintf(stderr, 
"ERROR: fuse_lowlevel_notify_store() failed with %s (%d)\n",
   320                         strerror(-ret), -ret);
   327                                                 0, (
void*) strdup(file_contents));
   328             if (-ret == ENODEV) { 
   332             if(retrieve_status == 0)
   335         sleep(options.update_interval);
   340 static void show_help(
const char *progname)
   342     printf(
"usage: %s [options] <mountpoint>\n\n", progname);
   343     printf(
"File-system specific options:\n"   344                "    --update-interval=<secs>  Update-rate of file system contents\n"   345                "    --no-notify            Disable kernel notifications\n"   349 int main(
int argc, 
char *argv[]) {
   351     struct fuse_session *se;
   352     struct fuse_cmdline_opts opts;
   361     if (opts.show_help) {
   367     } 
else if (opts.show_version) {
   378                           sizeof(tfs_oper), NULL);
   391     ret = pthread_create(&updater, NULL, update_fs_loop, (
void *)se);
   393         fprintf(stderr, 
"pthread_create failed with %s\n",
   399     if (opts.singlethread)
   402         ret = fuse_session_loop_mt(se, opts.clone_fd);
   404     assert(retrieve_status != 1);
   411     free(opts.mountpoint);
 void(* lookup)(fuse_req_t req, fuse_ino_t parent, const char *name)
struct fuse_session * fuse_session_new(struct fuse_args *args, const struct fuse_lowlevel_ops *op, size_t op_size, void *userdata)
int fuse_lowlevel_notify_retrieve(struct fuse_session *se, fuse_ino_t ino, size_t size, off_t offset, void *cookie)
void fuse_session_unmount(struct fuse_session *se)
void fuse_lowlevel_version(void)
int fuse_session_loop(struct fuse_session *se)
int fuse_reply_entry(fuse_req_t req, const struct fuse_entry_param *e)
size_t fuse_add_direntry(fuse_req_t req, char *buf, size_t bufsize, const char *name, const struct stat *stbuf, off_t off)
int fuse_opt_parse(struct fuse_args *args, void *data, const struct fuse_opt opts[], fuse_opt_proc_t proc)
int fuse_parse_cmdline(struct fuse_args *args, struct fuse_cmdline_opts *opts)
int fuse_set_signal_handlers(struct fuse_session *se)
const char * fuse_pkgversion(void)
int fuse_reply_err(fuse_req_t req, int err)
struct fuse_req * fuse_req_t
void fuse_remove_signal_handlers(struct fuse_session *se)
#define FUSE_ARGS_INIT(argc, argv)
void fuse_reply_none(fuse_req_t req)
int fuse_reply_open(fuse_req_t req, const struct fuse_file_info *fi)
void fuse_session_destroy(struct fuse_session *se)
int fuse_session_mount(struct fuse_session *se, const char *mountpoint)
enum fuse_buf_flags flags
void fuse_lowlevel_help(void)
int fuse_lowlevel_notify_store(struct fuse_session *se, fuse_ino_t ino, off_t offset, struct fuse_bufvec *bufv, enum fuse_buf_copy_flags flags)
void fuse_cmdline_help(void)
int fuse_reply_buf(fuse_req_t req, const char *buf, size_t size)
ssize_t fuse_buf_copy(struct fuse_bufvec *dst, struct fuse_bufvec *src, enum fuse_buf_copy_flags flags)
int fuse_reply_attr(fuse_req_t req, const struct stat *attr, double attr_timeout)
int fuse_daemonize(int foreground)
void fuse_opt_free_args(struct fuse_args *args)