23#define FUSE_USE_VERSION 34 
   30#include <fuse_lowlevel.h> 
   31#include <fuse_kernel.h> 
   39#include <sys/socket.h> 
   42static const char *hello_str = 
"Hello World!\n";
 
   43static const char *hello_name = 
"hello";
 
   45static int hello_stat(
fuse_ino_t ino, 
struct stat *stbuf)
 
   50                stbuf->st_mode = S_IFDIR | 0755;
 
   55                stbuf->st_mode = S_IFREG | 0444;
 
   57                stbuf->st_size = strlen(hello_str);
 
   73        memset(&stbuf, 0, 
sizeof(stbuf));
 
   74        if (hello_stat(ino, &stbuf) == -1)
 
   80static void hello_ll_init(
void *userdata, 
struct fuse_conn_info *conn)
 
   92        if (parent != 1 || strcmp(name, hello_name) != 0)
 
   95                memset(&e, 0, 
sizeof(e));
 
   98                e.entry_timeout = 1.0;
 
   99                hello_stat(e.ino, &e.attr);
 
  110static void dirbuf_add(
fuse_req_t req, 
struct dirbuf *b, 
const char *name,
 
  114        size_t oldsize = b->size;
 
  116        b->p = (
char *) realloc(b->p, b->size);
 
  117        memset(&stbuf, 0, 
sizeof(stbuf));
 
  123#define min(x, y) ((x) < (y) ? (x) : (y)) 
  125static int reply_buf_limited(
fuse_req_t req, 
const char *buf, 
size_t bufsize,
 
  126                             off_t off, 
size_t maxsize)
 
  130                                      min(bufsize - off, maxsize));
 
  145                memset(&b, 0, 
sizeof(b));
 
  146                dirbuf_add(req, &b, 
".", 1);
 
  147                dirbuf_add(req, &b, 
"..", 1);
 
  148                dirbuf_add(req, &b, hello_name, 2);
 
  149                reply_buf_limited(req, b.p, b.size, off, size);
 
  159        else if ((fi->
flags & O_ACCMODE) != O_RDONLY)
 
  171        reply_buf_limited(req, hello_str, strlen(hello_str), off, size);
 
  175        .
init           = hello_ll_init,
 
  176        .lookup         = hello_ll_lookup,
 
  177        .getattr        = hello_ll_getattr,
 
  178        .readdir        = hello_ll_readdir,
 
  179        .open           = hello_ll_open,
 
  180        .read           = hello_ll_read,
 
  183static int create_socket(
const char *socket_path) {
 
  184        struct sockaddr_un addr;
 
  186        if (strnlen(socket_path, 
sizeof(addr.sun_path)) >=
 
  187                sizeof(addr.sun_path)) {
 
  188                printf(
"Socket path may not be longer than %zu characters\n",
 
  189                       sizeof(addr.sun_path) - 1);
 
  193        if (remove(socket_path) == -1 && errno != ENOENT) {
 
  194                printf(
"Could not delete previous socket file entry at %s. Error: " 
  195                         "%s\n", socket_path, strerror(errno));
 
  199        memset(&addr, 0, 
sizeof(
struct sockaddr_un));
 
  200        strcpy(addr.sun_path, socket_path);
 
  202        int sfd = socket(AF_UNIX, SOCK_STREAM, 0);
 
  204                printf(
"Could not create socket. Error: %s\n", strerror(errno));
 
  208        addr.sun_family = AF_UNIX;
 
  209        if (bind(sfd, (
struct sockaddr *) &addr,
 
  210                   sizeof(
struct sockaddr_un)) == -1) {
 
  211                printf(
"Could not bind socket. Error: %s\n", strerror(errno));
 
  215        if (listen(sfd, 1) == -1)
 
  218        printf(
"Awaiting connection on socket at %s...\n", socket_path);
 
  219        int cfd = accept(sfd, NULL, NULL);
 
  221                printf(
"Could not accept connection. Error: %s\n",
 
  225                printf(
"Accepted connection!\n");
 
  230static ssize_t stream_writev(
int fd, 
struct iovec *iov, 
int count,
 
  237                written = writev(fd, iov+cur, count-cur);
 
  241                while (cur < count && written >= iov[cur].iov_len)
 
  242                        written -= iov[cur++].iov_len;
 
  246                iov[cur].iov_base = (
char *)iov[cur].iov_base + written;
 
  247                iov[cur].iov_len -= written;
 
  253static ssize_t readall(
int fd, 
void *buf, 
size_t len) {
 
  256        while (count < len) {
 
  257                int i = read(fd, (
char *)buf + count, len - count);
 
  269static ssize_t stream_read(
int fd, 
void *buf, 
size_t buf_len, 
void *userdata) {
 
  272        int res = readall(fd, buf, 
sizeof(
struct fuse_in_header));
 
  277    uint32_t packet_len = ((
struct fuse_in_header *)buf)->len;
 
  278    if (packet_len > buf_len)
 
  283    res = readall(fd, (
char *)buf + 
sizeof(
struct fuse_in_header),
 
  284                  packet_len - 
sizeof(
struct fuse_in_header));
 
  286    return  (res == -1) ? res : (res + prev_res);
 
  289static ssize_t stream_splice_send(
int fdin, off_t *offin, 
int fdout,
 
  290                                            off_t *offout, 
size_t len,
 
  291                                  unsigned int flags, 
void *userdata) {
 
  295        while (count < len) {
 
  296                int i = splice(fdin, offin, fdout, offout, len - count, flags);
 
  305static void fuse_cmdline_help_uds(
void)
 
  307        printf(
"    -h   --help            print help\n" 
  308               "    -V   --version         print version\n" 
  309               "    -d   -o debug          enable debug output (implies -f)\n");
 
  312int main(
int argc, 
char *argv[])
 
  315        struct fuse_session *se;
 
  317        const struct fuse_custom_io io = {
 
  318                .writev = stream_writev,
 
  320                .splice_receive = NULL,
 
  321                .splice_send = stream_splice_send,
 
  326        if (fuse_parse_cmdline(&args, &opts) != 0)
 
  328        if (opts.show_help) {
 
  329                printf(
"usage: %s [options]\n\n", argv[0]);
 
  330                fuse_cmdline_help_uds();
 
  334        } 
else if (opts.show_version) {
 
  341        se = fuse_session_new(&args, &hello_ll_oper,
 
  342                              sizeof(hello_ll_oper), NULL);
 
  349        cfd = create_socket(
"/tmp/libfuse-hello-ll.sock");
 
  353        if (fuse_session_custom_io(se, &io, cfd) != 0)
 
  363        free(opts.mountpoint);
 
int fuse_set_signal_handlers(struct fuse_session *se)
const char * fuse_pkgversion(void)
void fuse_remove_signal_handlers(struct fuse_session *se)
void fuse_session_destroy(struct fuse_session *se)
int fuse_reply_open(fuse_req_t req, const struct fuse_file_info *fi)
int fuse_reply_err(fuse_req_t req, int err)
int fuse_reply_buf(fuse_req_t req, const char *buf, size_t size)
struct fuse_req * fuse_req_t
int fuse_session_loop(struct fuse_session *se)
int fuse_reply_entry(fuse_req_t req, const struct fuse_entry_param *e)
void fuse_lowlevel_help(void)
void fuse_lowlevel_version(void)
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_reply_attr(fuse_req_t req, const struct stat *attr, double attr_timeout)
void fuse_opt_free_args(struct fuse_args *args)
#define FUSE_ARGS_INIT(argc, argv)
void(* init)(void *userdata, struct fuse_conn_info *conn)