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/*
FUSE: Filesystem in Userspace
Copyright (C) 2001-2007 Miklos Szeredi <miklos@szeredi.hu>
This program can be distributed under the terms of the GNU GPL.
See the file COPYING.
*/
/** @file
*
* hello.c - minimal FUSE example featuring fuse_main usage
*
* \section section_compile compiling this example
*
* gcc -Wall hello.c `pkg-config fuse --cflags --libs` -o hello
*
* \section section_usage usage
\verbatim
% mkdir mnt
% ./hello mnt # program will vanish into the background
% ls -la mnt
total 4
drwxr-xr-x 2 root root 0 Jan 1 1970 ./
drwxrwx--- 1 root vboxsf 4096 Jun 16 23:12 ../
-r--r--r-- 1 root root 13 Jan 1 1970 hello
% cat mnt/hello
Hello World!
% fusermount -u mnt
\endverbatim
*
* \section section_source the complete source
* \include hello.c
*/
#define FUSE_USE_VERSION 30
#include <fuse.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>
static const char *hello_str = "Hello World!\n";
static const char *hello_path = "/hello";
static int hello_getattr(const char *path, struct stat *stbuf)
{
int res = 0;
memset(stbuf, 0, sizeof(struct stat));
if (strcmp(path, "/") == 0) {
stbuf->st_mode = S_IFDIR | 0755;
stbuf->st_nlink = 2;
} else if (strcmp(path, hello_path) == 0) {
stbuf->st_mode = S_IFREG | 0444;
stbuf->st_nlink = 1;
stbuf->st_size = strlen(hello_str);
} else
res = -ENOENT;
return res;
}
static int hello_readdir(const char *path, void *buf, fuse_fill_dir_t filler,
off_t offset, struct fuse_file_info *fi)
{
(void) offset;
(void) fi;
if (strcmp(path, "/") != 0)
return -ENOENT;
filler(buf, ".", NULL, 0);
filler(buf, "..", NULL, 0);
filler(buf, hello_path + 1, NULL, 0);
return 0;
}
static int hello_open(const char *path, struct fuse_file_info *fi)
{
if (strcmp(path, hello_path) != 0)
return -ENOENT;
if ((fi->flags & 3) != O_RDONLY)
return -EACCES;
return 0;
}
static int hello_read(const char *path, char *buf, size_t size, off_t offset,
struct fuse_file_info *fi)
{
size_t len;
(void) fi;
if(strcmp(path, hello_path) != 0)
return -ENOENT;
len = strlen(hello_str);
if (offset < len) {
if (offset + size > len)
size = len - offset;
memcpy(buf, hello_str + offset, size);
} else
size = 0;
return size;
}
// fuse_operations hello_oper is redirecting function-calls to _our_ functions implemented above
static struct fuse_operations hello_oper = {
.getattr = hello_getattr,
.readdir = hello_readdir,
.open = hello_open,
.read = hello_read,
};
// in the main function we call the blocking fuse_main(..) function with &hello_oper
int main(int argc, char *argv[])
{
return fuse_main(argc, argv, &hello_oper, NULL);
}
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