moved FUSE impl into separate file, more work on inodes

Cargo.lock

@@ -122,6 +122,7 @@ dependencies = [
  "fuser",
  "libc",
  "log",
+ "rand",
  "thiserror",
 ]
 
@@ -141,6 +142,18 @@ dependencies = [
  "zerocopy",
 ]
 
+[[package]]
+name = "getrandom"
+version = "0.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "26145e563e54f2cadc477553f1ec5ee650b00862f0a58bcd12cbdc5f0ea2d2f4"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "r-efi",
+ "wasi",
+]
+
 [[package]]
 name = "iana-time-zone"
 version = "0.1.63"
@@ -254,6 +267,30 @@ dependencies = [
  "proc-macro2",
 ]
 
+[[package]]
+name = "r-efi"
+version = "5.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "69cdb34c158ceb288df11e18b4bd39de994f6657d83847bdffdbd7f346754b0f"
+
+[[package]]
+name = "rand"
+version = "0.9.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6db2770f06117d490610c7488547d543617b21bfa07796d7a12f6f1bd53850d1"
+dependencies = [
+ "rand_core",
+]
+
+[[package]]
+name = "rand_core"
+version = "0.9.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "99d9a13982dcf210057a8a78572b2217b667c3beacbf3a0d8b454f6f82837d38"
+dependencies = [
+ "getrandom",
+]
+
 [[package]]
 name = "rustversion"
 version = "1.0.21"
@@ -315,6 +352,15 @@ version = "1.0.18"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5a5f39404a5da50712a4c1eecf25e90dd62b613502b7e925fd4e4d19b5c96512"
 
+[[package]]
+name = "wasi"
+version = "0.14.2+wasi-0.2.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9683f9a5a998d873c0d21fcbe3c083009670149a8fab228644b8bd36b2c48cb3"
+dependencies = [
+ "wit-bindgen-rt",
+]
+
 [[package]]
 name = "wasm-bindgen"
 version = "0.2.100"
@@ -454,6 +500,15 @@ dependencies = [
  "windows-link",
 ]
 
+[[package]]
+name = "wit-bindgen-rt"
+version = "0.39.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6f42320e61fe2cfd34354ecb597f86f413484a798ba44a8ca1165c58d42da6c1"
+dependencies = [
+ "bitflags",
+]
+
 [[package]]
 name = "zerocopy"
 version = "0.8.26"

fat-bits/src/lib.rs

@@ -2,7 +2,7 @@ use std::cell::RefCell;
 use std::io::{Read, Seek, SeekFrom, Write};
 use std::rc::Rc;
 
-use crate::dir::{DirEntry, DirIter};
+use crate::dir::DirIter;
 use crate::fat::{FatError, Fatty};
 use crate::subslice::{SubSlice, SubSliceMut};
 
@@ -217,7 +217,12 @@ impl FatFs {
         Ok(data)
     }
 
-    pub fn root_dir_iter(&self) -> Box<dyn Iterator<Item = DirEntry> + '_> {
+    fn chain_reader(&self, first_cluster: u32) -> impl Read {
+        iter::ClusterChainReader::new(self, first_cluster)
+    }
+
+    pub fn root_dir_iter<'a>(&'a self) -> DirIter<Box<dyn Read + 'a>> {
+        // Box<dyn Iterator<Item = DirEntry> + '_>
         // TODO: maybe wrap this in another RootDirIter enum, so we don't have to Box<dyn>
 
         if let Some(root_dir_offset) = self.root_dir_offset {
@@ -225,7 +230,7 @@ impl FatFs {
 
             let sub_slice = SubSlice::new(self, root_dir_offset, self.root_dir_size);
 
-            return Box::new(DirIter::new(sub_slice));
+            return DirIter::new(Box::new(sub_slice));
         }
 
         // FAT32
@@ -235,10 +240,15 @@ impl FatFs {
 
         let cluster_iter = iter::ClusterChainReader::new(self, root_cluster);
 
-        Box::new(DirIter::new(cluster_iter))
+        DirIter::new(Box::new(cluster_iter))
     }
 
-    pub fn chain_reader(&self, first_cluster: u32) -> impl Read {
-        iter::ClusterChainReader::new(self, first_cluster)
+    pub fn dir_iter<'a>(&'a self, first_cluster: u32) -> DirIter<Box<dyn Read + 'a>> {
+        // TODO: return type must match root_dir_iter
+        // if the Box<dyn> is changed there, update here as well
+
+        let cluster_iter = self.chain_reader(first_cluster);
+
+        DirIter::new(Box::new(cluster_iter))
     }
 }

fat-dump/src/main.rs

@@ -68,9 +68,7 @@ fn tree(fat_fs: &FatFs, show_hidden: bool) {
             }
 
             if dir_entry.is_dir() {
-                let reader = fat_fs.chain_reader(dir_entry.first_cluster());
-
-                let iter = DirIter::new(reader);
+                let iter = fat_fs.dir_iter(dir_entry.first_cluster());
 
                 tree_impl(fat_fs, iter, show_hidden, indent + 1);
             }

fat-fuse/Cargo.toml

@@ -10,4 +10,5 @@ fat-bits = { version = "0.1.0", path = "../fat-bits" }
 fuser = "0.15.1"
 libc = "0.2.174"
 log = "0.4.27"
+rand = { version = "0.9.2", default-features = false, features = ["os_rng", "small_rng"] }
 thiserror = "2.0.12"

fat-fuse/src/fuse.rs

@@ -0,0 +1,572 @@
+use std::ffi::c_int;
+use std::time::Duration;
+
+use fuser::Filesystem;
+use libc::{EIO, ENOENT, ENOSYS, ENOTDIR, EPERM};
+use log::{debug, warn};
+
+use crate::FatFuse;
+
+impl Filesystem for FatFuse {
+    fn init(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        _config: &mut fuser::KernelConfig,
+    ) -> Result<(), c_int> {
+        Ok(())
+    }
+
+    fn destroy(&mut self) {}
+
+    fn lookup(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        parent: u64,
+        name: &std::ffi::OsStr,
+        reply: fuser::ReplyEntry,
+    ) {
+        // warn!("[Not Implemented] lookup(parent: {:#x?}, name {:?})", parent, name);
+        // reply.error(ENOSYS);
+
+        let parent_inode = if let Some(inode) = self.get_inode(parent) {
+            inode
+        } else {
+            // parent inode does not exist
+            // TODO: how can we make sure this does not exist?
+            // panic?
+            reply.error(EIO);
+
+            return;
+        };
+
+        let Ok(dir_iter) = parent_inode.dir_iter(&self.fat_fs) else {
+            reply.error(ENOTDIR);
+            return;
+        };
+
+        let Some(dir_entry) =
+            dir_iter.find(|dir_entry| dir_entry.name_str().as_deref() == Some(""))
+        else {
+            reply.error(ENOENT);
+            return;
+        };
+
+        reply.entry(&Duration::from_secs(1), attr, generation);
+
+        todo!();
+    }
+
+    fn forget(&mut self, _req: &fuser::Request<'_>, _ino: u64, _nlookup: u64) {}
+
+    fn getattr(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        ino: u64,
+        fh: Option<u64>,
+        reply: fuser::ReplyAttr,
+    ) {
+        warn!("[Not Implemented] getattr(ino: {:#x?}, fh: {:#x?})", ino, fh);
+        reply.error(ENOSYS);
+    }
+
+    fn setattr(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        ino: u64,
+        mode: Option<u32>,
+        uid: Option<u32>,
+        gid: Option<u32>,
+        size: Option<u64>,
+        _atime: Option<fuser::TimeOrNow>,
+        _mtime: Option<fuser::TimeOrNow>,
+        _ctime: Option<std::time::SystemTime>,
+        fh: Option<u64>,
+        _crtime: Option<std::time::SystemTime>,
+        _chgtime: Option<std::time::SystemTime>,
+        _bkuptime: Option<std::time::SystemTime>,
+        flags: Option<u32>,
+        reply: fuser::ReplyAttr,
+    ) {
+        debug!(
+            "[Not Implemented] setattr(ino: {:#x?}, mode: {:?}, uid: {:?}, \
+            gid: {:?}, size: {:?}, fh: {:?}, flags: {:?})",
+            ino, mode, uid, gid, size, fh, flags
+        );
+        reply.error(ENOSYS);
+    }
+
+    fn readlink(&mut self, _req: &fuser::Request<'_>, ino: u64, reply: fuser::ReplyData) {
+        debug!("[Not Implemented] readlink(ino: {:#x?})", ino);
+        reply.error(ENOSYS);
+    }
+
+    fn mknod(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        parent: u64,
+        name: &std::ffi::OsStr,
+        mode: u32,
+        umask: u32,
+        rdev: u32,
+        reply: fuser::ReplyEntry,
+    ) {
+        debug!(
+            "[Not Implemented] mknod(parent: {:#x?}, name: {:?}, mode: {}, \
+            umask: {:#x?}, rdev: {})",
+            parent, name, mode, umask, rdev
+        );
+        reply.error(ENOSYS);
+    }
+
+    fn mkdir(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        parent: u64,
+        name: &std::ffi::OsStr,
+        mode: u32,
+        umask: u32,
+        reply: fuser::ReplyEntry,
+    ) {
+        debug!(
+            "[Not Implemented] mkdir(parent: {:#x?}, name: {:?}, mode: {}, umask: {:#x?})",
+            parent, name, mode, umask
+        );
+        reply.error(ENOSYS);
+    }
+
+    fn unlink(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        parent: u64,
+        name: &std::ffi::OsStr,
+        reply: fuser::ReplyEmpty,
+    ) {
+        debug!("[Not Implemented] unlink(parent: {:#x?}, name: {:?})", parent, name,);
+        reply.error(ENOSYS);
+    }
+
+    fn rmdir(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        parent: u64,
+        name: &std::ffi::OsStr,
+        reply: fuser::ReplyEmpty,
+    ) {
+        debug!("[Not Implemented] rmdir(parent: {:#x?}, name: {:?})", parent, name,);
+        reply.error(ENOSYS);
+    }
+
+    fn symlink(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        parent: u64,
+        link_name: &std::ffi::OsStr,
+        target: &std::path::Path,
+        reply: fuser::ReplyEntry,
+    ) {
+        debug!(
+            "[Not Implemented] symlink(parent: {:#x?}, link_name: {:?}, target: {:?})",
+            parent, link_name, target,
+        );
+        reply.error(EPERM);
+    }
+
+    fn rename(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        parent: u64,
+        name: &std::ffi::OsStr,
+        newparent: u64,
+        newname: &std::ffi::OsStr,
+        flags: u32,
+        reply: fuser::ReplyEmpty,
+    ) {
+        debug!(
+            "[Not Implemented] rename(parent: {:#x?}, name: {:?}, newparent: {:#x?}, \
+            newname: {:?}, flags: {})",
+            parent, name, newparent, newname, flags,
+        );
+        reply.error(ENOSYS);
+    }
+
+    fn link(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        ino: u64,
+        newparent: u64,
+        newname: &std::ffi::OsStr,
+        reply: fuser::ReplyEntry,
+    ) {
+        debug!(
+            "[Not Implemented] link(ino: {:#x?}, newparent: {:#x?}, newname: {:?})",
+            ino, newparent, newname
+        );
+        reply.error(EPERM);
+    }
+
+    fn open(&mut self, _req: &fuser::Request<'_>, _ino: u64, _flags: i32, reply: fuser::ReplyOpen) {
+        reply.opened(0, 0);
+    }
+
+    fn read(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        ino: u64,
+        fh: u64,
+        offset: i64,
+        size: u32,
+        flags: i32,
+        lock_owner: Option<u64>,
+        reply: fuser::ReplyData,
+    ) {
+        warn!(
+            "[Not Implemented] read(ino: {:#x?}, fh: {}, offset: {}, size: {}, \
+            flags: {:#x?}, lock_owner: {:?})",
+            ino, fh, offset, size, flags, lock_owner
+        );
+        reply.error(ENOSYS);
+    }
+
+    fn write(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        ino: u64,
+        fh: u64,
+        offset: i64,
+        data: &[u8],
+        write_flags: u32,
+        flags: i32,
+        lock_owner: Option<u64>,
+        reply: fuser::ReplyWrite,
+    ) {
+        debug!(
+            "[Not Implemented] write(ino: {:#x?}, fh: {}, offset: {}, data.len(): {}, \
+            write_flags: {:#x?}, flags: {:#x?}, lock_owner: {:?})",
+            ino,
+            fh,
+            offset,
+            data.len(),
+            write_flags,
+            flags,
+            lock_owner
+        );
+        reply.error(ENOSYS);
+    }
+
+    fn flush(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        ino: u64,
+        fh: u64,
+        lock_owner: u64,
+        reply: fuser::ReplyEmpty,
+    ) {
+        debug!(
+            "[Not Implemented] flush(ino: {:#x?}, fh: {}, lock_owner: {:?})",
+            ino, fh, lock_owner
+        );
+        reply.error(ENOSYS);
+    }
+
+    fn release(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        _ino: u64,
+        _fh: u64,
+        _flags: i32,
+        _lock_owner: Option<u64>,
+        _flush: bool,
+        reply: fuser::ReplyEmpty,
+    ) {
+        reply.ok();
+    }
+
+    fn fsync(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        ino: u64,
+        fh: u64,
+        datasync: bool,
+        reply: fuser::ReplyEmpty,
+    ) {
+        debug!("[Not Implemented] fsync(ino: {:#x?}, fh: {}, datasync: {})", ino, fh, datasync);
+        reply.error(ENOSYS);
+    }
+
+    fn opendir(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        _ino: u64,
+        _flags: i32,
+        reply: fuser::ReplyOpen,
+    ) {
+        reply.opened(0, 0);
+    }
+
+    fn readdir(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        ino: u64,
+        fh: u64,
+        offset: i64,
+        reply: fuser::ReplyDirectory,
+    ) {
+        warn!("[Not Implemented] readdir(ino: {:#x?}, fh: {}, offset: {})", ino, fh, offset);
+        reply.error(ENOSYS);
+    }
+
+    fn readdirplus(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        ino: u64,
+        fh: u64,
+        offset: i64,
+        reply: fuser::ReplyDirectoryPlus,
+    ) {
+        debug!(
+            "[Not Implemented] readdirplus(ino: {:#x?}, fh: {}, offset: {})",
+            ino, fh, offset
+        );
+        reply.error(ENOSYS);
+    }
+
+    fn releasedir(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        _ino: u64,
+        _fh: u64,
+        _flags: i32,
+        reply: fuser::ReplyEmpty,
+    ) {
+        reply.ok();
+    }
+
+    fn fsyncdir(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        ino: u64,
+        fh: u64,
+        datasync: bool,
+        reply: fuser::ReplyEmpty,
+    ) {
+        debug!(
+            "[Not Implemented] fsyncdir(ino: {:#x?}, fh: {}, datasync: {})",
+            ino, fh, datasync
+        );
+        reply.error(ENOSYS);
+    }
+
+    fn statfs(&mut self, _req: &fuser::Request<'_>, _ino: u64, reply: fuser::ReplyStatfs) {
+        reply.statfs(0, 0, 0, 0, 0, 512, 255, 0);
+    }
+
+    fn setxattr(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        ino: u64,
+        name: &std::ffi::OsStr,
+        _value: &[u8],
+        flags: i32,
+        position: u32,
+        reply: fuser::ReplyEmpty,
+    ) {
+        debug!(
+            "[Not Implemented] setxattr(ino: {:#x?}, name: {:?}, flags: {:#x?}, position: {})",
+            ino, name, flags, position
+        );
+        reply.error(ENOSYS);
+    }
+
+    fn getxattr(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        ino: u64,
+        name: &std::ffi::OsStr,
+        size: u32,
+        reply: fuser::ReplyXattr,
+    ) {
+        debug!("[Not Implemented] getxattr(ino: {:#x?}, name: {:?}, size: {})", ino, name, size);
+        reply.error(ENOSYS);
+    }
+
+    fn listxattr(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        ino: u64,
+        size: u32,
+        reply: fuser::ReplyXattr,
+    ) {
+        debug!("[Not Implemented] listxattr(ino: {:#x?}, size: {})", ino, size);
+        reply.error(ENOSYS);
+    }
+
+    fn removexattr(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        ino: u64,
+        name: &std::ffi::OsStr,
+        reply: fuser::ReplyEmpty,
+    ) {
+        debug!("[Not Implemented] removexattr(ino: {:#x?}, name: {:?})", ino, name);
+        reply.error(ENOSYS);
+    }
+
+    fn access(&mut self, _req: &fuser::Request<'_>, ino: u64, mask: i32, reply: fuser::ReplyEmpty) {
+        debug!("[Not Implemented] access(ino: {:#x?}, mask: {})", ino, mask);
+        reply.error(ENOSYS);
+    }
+
+    fn create(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        parent: u64,
+        name: &std::ffi::OsStr,
+        mode: u32,
+        umask: u32,
+        flags: i32,
+        reply: fuser::ReplyCreate,
+    ) {
+        debug!(
+            "[Not Implemented] create(parent: {:#x?}, name: {:?}, mode: {}, umask: {:#x?}, \
+            flags: {:#x?})",
+            parent, name, mode, umask, flags
+        );
+        reply.error(ENOSYS);
+    }
+
+    fn getlk(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        ino: u64,
+        fh: u64,
+        lock_owner: u64,
+        start: u64,
+        end: u64,
+        typ: i32,
+        pid: u32,
+        reply: fuser::ReplyLock,
+    ) {
+        debug!(
+            "[Not Implemented] getlk(ino: {:#x?}, fh: {}, lock_owner: {}, start: {}, \
+            end: {}, typ: {}, pid: {})",
+            ino, fh, lock_owner, start, end, typ, pid
+        );
+        reply.error(ENOSYS);
+    }
+
+    fn setlk(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        ino: u64,
+        fh: u64,
+        lock_owner: u64,
+        start: u64,
+        end: u64,
+        typ: i32,
+        pid: u32,
+        sleep: bool,
+        reply: fuser::ReplyEmpty,
+    ) {
+        debug!(
+            "[Not Implemented] setlk(ino: {:#x?}, fh: {}, lock_owner: {}, start: {}, \
+            end: {}, typ: {}, pid: {}, sleep: {})",
+            ino, fh, lock_owner, start, end, typ, pid, sleep
+        );
+        reply.error(ENOSYS);
+    }
+
+    fn bmap(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        ino: u64,
+        blocksize: u32,
+        idx: u64,
+        reply: fuser::ReplyBmap,
+    ) {
+        debug!(
+            "[Not Implemented] bmap(ino: {:#x?}, blocksize: {}, idx: {})",
+            ino, blocksize, idx,
+        );
+        reply.error(ENOSYS);
+    }
+
+    fn ioctl(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        ino: u64,
+        fh: u64,
+        flags: u32,
+        cmd: u32,
+        in_data: &[u8],
+        out_size: u32,
+        reply: fuser::ReplyIoctl,
+    ) {
+        debug!(
+            "[Not Implemented] ioctl(ino: {:#x?}, fh: {}, flags: {}, cmd: {}, \
+            in_data.len(): {}, out_size: {})",
+            ino,
+            fh,
+            flags,
+            cmd,
+            in_data.len(),
+            out_size,
+        );
+        reply.error(ENOSYS);
+    }
+
+    fn fallocate(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        ino: u64,
+        fh: u64,
+        offset: i64,
+        length: i64,
+        mode: i32,
+        reply: fuser::ReplyEmpty,
+    ) {
+        debug!(
+            "[Not Implemented] fallocate(ino: {:#x?}, fh: {}, offset: {}, \
+            length: {}, mode: {})",
+            ino, fh, offset, length, mode
+        );
+        reply.error(ENOSYS);
+    }
+
+    fn lseek(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        ino: u64,
+        fh: u64,
+        offset: i64,
+        whence: i32,
+        reply: fuser::ReplyLseek,
+    ) {
+        debug!(
+            "[Not Implemented] lseek(ino: {:#x?}, fh: {}, offset: {}, whence: {})",
+            ino, fh, offset, whence
+        );
+        reply.error(ENOSYS);
+    }
+
+    fn copy_file_range(
+        &mut self,
+        _req: &fuser::Request<'_>,
+        ino_in: u64,
+        fh_in: u64,
+        offset_in: i64,
+        ino_out: u64,
+        fh_out: u64,
+        offset_out: i64,
+        len: u64,
+        flags: u32,
+        reply: fuser::ReplyWrite,
+    ) {
+        debug!(
+            "[Not Implemented] copy_file_range(ino_in: {:#x?}, fh_in: {}, \
+            offset_in: {}, ino_out: {:#x?}, fh_out: {}, offset_out: {}, \
+            len: {}, flags: {})",
+            ino_in, fh_in, offset_in, ino_out, fh_out, offset_out, len, flags
+        );
+        reply.error(ENOSYS);
+    }
+}

fat-fuse/src/inode.rs

@@ -1,11 +1,35 @@
+use std::cell::{LazyCell, RefCell};
 use std::time::SystemTime;
 
 use chrono::{NaiveDateTime, NaiveTime};
 use fat_bits::FatFs;
-use fat_bits::dir::DirEntry;
+use fat_bits::dir::{DirEntry, DirIter};
 use fuser::FileAttr;
+use rand::{Rng, SeedableRng as _};
 
-#[derive(Debug, Clone, Copy)]
+thread_local! {
+/// SAFETY
+///
+/// do not access this directly, only invoke the get_random_u32 function
+// static RNG: LazyCell<UnsafeCell<rand::rngs::SmallRng>> = LazyCell::new(|| UnsafeCell::new(rand::rngs::SmallRng::from_os_rng()));
+
+/// performance should not be a bottleneck here, since we only need to occasionally generate u32s to
+/// be used as generations in inodes
+/// if at some point (contrary to expectations) it should become, can switch it to an UnsafeCell
+static RNG: LazyCell<RefCell<rand::rngs::SmallRng>> = LazyCell::new(|| RefCell::new(rand::rngs::SmallRng::from_os_rng()));
+}
+
+fn get_random_u32() -> u32 {
+    // RNG.with(|x| unsafe {
+    //     let rng = &mut (*x.get());
+
+    //     rng.random::<u32>()
+    // })
+
+    RNG.with(|rng| rng.borrow_mut().random())
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum Kind {
     File,
     Dir,
@@ -20,13 +44,15 @@ impl From<Kind> for fuser::FileType {
     }
 }
 
+const ROOT_INO: u64 = 1;
+
 #[derive(Debug)]
 #[allow(dead_code)]
 pub struct Inode {
     ino: u64,
+    generation: u32,
 
     size: u64,
-    // blocks: u64,
     block_size: u32,
 
     kind: Kind,
@@ -49,6 +75,8 @@ impl Inode {
     pub fn new(fat_fs: &FatFs, dir_entry: DirEntry, uid: u32, gid: u32) -> Inode {
         assert!(dir_entry.is_file() || dir_entry.is_dir());
 
+        let generation = get_random_u32();
+
         let kind = if dir_entry.is_dir() {
             Kind::Dir
         } else {
@@ -69,6 +97,7 @@ impl Inode {
 
         Inode {
             ino: dir_entry.first_cluster() as u64,
+            generation,
             size: dir_entry.file_size() as u64,
             block_size: fat_fs.bpb().bytes_per_sector() as u32,
             kind,
@@ -103,4 +132,22 @@ impl Inode {
             flags: 0,
         }
     }
+
+    pub fn dir_iter(&self, fat_fs: &FatFs) -> anyhow::Result<impl Iterator<Item = DirEntry>> {
+        anyhow::ensure!(self.kind == Kind::Dir, "cannot dir_iter on a file");
+
+        // TODO: the boxing here is not particularly pretty, but neccessary, since the DirIter for
+        // the root holds a
+
+        if self.ino == ROOT_INO {
+            // root dir
+
+            return Ok(fat_fs.root_dir_iter());
+        }
+
+        let chain_reader = fat_fs.chain_reader(self.first_cluster);
+
+        // TODO: get rid of this Box if the boxing is removed from root_dir_iter
+        Ok(DirIter::new(Box::new(chain_reader)))
+    }
 }

fat-fuse/src/lib.rs

@@ -1,14 +1,11 @@
+mod fuse;
 mod inode;
 
 use std::cell::RefCell;
 use std::collections::BTreeMap;
-use std::ffi::c_int;
 use std::rc::Rc;
 
 use fat_bits::{FatFs, SliceLike};
-use fuser::Filesystem;
-use libc::{ENOSYS, EPERM};
-use log::{debug, warn};
 
 use crate::inode::Inode;
 
@@ -19,6 +16,8 @@ pub struct FatFuse {
     uid: u32,
     gid: u32,
 
+    next_fd: u32,
+
     inode_table: BTreeMap<u64, Inode>,
 }
 
@@ -33,544 +32,16 @@ impl FatFuse {
             fat_fs,
             uid,
             gid,
+            next_fd: 0,
             inode_table: BTreeMap::new(),
         })
     }
-}
 
-impl Filesystem for FatFuse {
-    fn init(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        _config: &mut fuser::KernelConfig,
-    ) -> Result<(), c_int> {
-        Ok(())
+    fn get_inode(&self, ino: u64) -> Option<&Inode> {
+        self.inode_table.get(&ino)
     }
 
-    fn destroy(&mut self) {}
-
-    fn lookup(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        parent: u64,
-        name: &std::ffi::OsStr,
-        reply: fuser::ReplyEntry,
-    ) {
-        warn!("[Not Implemented] lookup(parent: {:#x?}, name {:?})", parent, name);
-        reply.error(ENOSYS);
-    }
-
-    fn forget(&mut self, _req: &fuser::Request<'_>, _ino: u64, _nlookup: u64) {}
-
-    fn getattr(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        ino: u64,
-        fh: Option<u64>,
-        reply: fuser::ReplyAttr,
-    ) {
-        warn!("[Not Implemented] getattr(ino: {:#x?}, fh: {:#x?})", ino, fh);
-        reply.error(ENOSYS);
-    }
-
-    fn setattr(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        ino: u64,
-        mode: Option<u32>,
-        uid: Option<u32>,
-        gid: Option<u32>,
-        size: Option<u64>,
-        _atime: Option<fuser::TimeOrNow>,
-        _mtime: Option<fuser::TimeOrNow>,
-        _ctime: Option<std::time::SystemTime>,
-        fh: Option<u64>,
-        _crtime: Option<std::time::SystemTime>,
-        _chgtime: Option<std::time::SystemTime>,
-        _bkuptime: Option<std::time::SystemTime>,
-        flags: Option<u32>,
-        reply: fuser::ReplyAttr,
-    ) {
-        debug!(
-            "[Not Implemented] setattr(ino: {:#x?}, mode: {:?}, uid: {:?}, \
-            gid: {:?}, size: {:?}, fh: {:?}, flags: {:?})",
-            ino, mode, uid, gid, size, fh, flags
-        );
-        reply.error(ENOSYS);
-    }
-
-    fn readlink(&mut self, _req: &fuser::Request<'_>, ino: u64, reply: fuser::ReplyData) {
-        debug!("[Not Implemented] readlink(ino: {:#x?})", ino);
-        reply.error(ENOSYS);
-    }
-
-    fn mknod(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        parent: u64,
-        name: &std::ffi::OsStr,
-        mode: u32,
-        umask: u32,
-        rdev: u32,
-        reply: fuser::ReplyEntry,
-    ) {
-        debug!(
-            "[Not Implemented] mknod(parent: {:#x?}, name: {:?}, mode: {}, \
-            umask: {:#x?}, rdev: {})",
-            parent, name, mode, umask, rdev
-        );
-        reply.error(ENOSYS);
-    }
-
-    fn mkdir(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        parent: u64,
-        name: &std::ffi::OsStr,
-        mode: u32,
-        umask: u32,
-        reply: fuser::ReplyEntry,
-    ) {
-        debug!(
-            "[Not Implemented] mkdir(parent: {:#x?}, name: {:?}, mode: {}, umask: {:#x?})",
-            parent, name, mode, umask
-        );
-        reply.error(ENOSYS);
-    }
-
-    fn unlink(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        parent: u64,
-        name: &std::ffi::OsStr,
-        reply: fuser::ReplyEmpty,
-    ) {
-        debug!("[Not Implemented] unlink(parent: {:#x?}, name: {:?})", parent, name,);
-        reply.error(ENOSYS);
-    }
-
-    fn rmdir(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        parent: u64,
-        name: &std::ffi::OsStr,
-        reply: fuser::ReplyEmpty,
-    ) {
-        debug!("[Not Implemented] rmdir(parent: {:#x?}, name: {:?})", parent, name,);
-        reply.error(ENOSYS);
-    }
-
-    fn symlink(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        parent: u64,
-        link_name: &std::ffi::OsStr,
-        target: &std::path::Path,
-        reply: fuser::ReplyEntry,
-    ) {
-        debug!(
-            "[Not Implemented] symlink(parent: {:#x?}, link_name: {:?}, target: {:?})",
-            parent, link_name, target,
-        );
-        reply.error(EPERM);
-    }
-
-    fn rename(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        parent: u64,
-        name: &std::ffi::OsStr,
-        newparent: u64,
-        newname: &std::ffi::OsStr,
-        flags: u32,
-        reply: fuser::ReplyEmpty,
-    ) {
-        debug!(
-            "[Not Implemented] rename(parent: {:#x?}, name: {:?}, newparent: {:#x?}, \
-            newname: {:?}, flags: {})",
-            parent, name, newparent, newname, flags,
-        );
-        reply.error(ENOSYS);
-    }
-
-    fn link(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        ino: u64,
-        newparent: u64,
-        newname: &std::ffi::OsStr,
-        reply: fuser::ReplyEntry,
-    ) {
-        debug!(
-            "[Not Implemented] link(ino: {:#x?}, newparent: {:#x?}, newname: {:?})",
-            ino, newparent, newname
-        );
-        reply.error(EPERM);
-    }
-
-    fn open(&mut self, _req: &fuser::Request<'_>, _ino: u64, _flags: i32, reply: fuser::ReplyOpen) {
-        reply.opened(0, 0);
-    }
-
-    fn read(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        ino: u64,
-        fh: u64,
-        offset: i64,
-        size: u32,
-        flags: i32,
-        lock_owner: Option<u64>,
-        reply: fuser::ReplyData,
-    ) {
-        warn!(
-            "[Not Implemented] read(ino: {:#x?}, fh: {}, offset: {}, size: {}, \
-            flags: {:#x?}, lock_owner: {:?})",
-            ino, fh, offset, size, flags, lock_owner
-        );
-        reply.error(ENOSYS);
-    }
-
-    fn write(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        ino: u64,
-        fh: u64,
-        offset: i64,
-        data: &[u8],
-        write_flags: u32,
-        flags: i32,
-        lock_owner: Option<u64>,
-        reply: fuser::ReplyWrite,
-    ) {
-        debug!(
-            "[Not Implemented] write(ino: {:#x?}, fh: {}, offset: {}, data.len(): {}, \
-            write_flags: {:#x?}, flags: {:#x?}, lock_owner: {:?})",
-            ino,
-            fh,
-            offset,
-            data.len(),
-            write_flags,
-            flags,
-            lock_owner
-        );
-        reply.error(ENOSYS);
-    }
-
-    fn flush(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        ino: u64,
-        fh: u64,
-        lock_owner: u64,
-        reply: fuser::ReplyEmpty,
-    ) {
-        debug!(
-            "[Not Implemented] flush(ino: {:#x?}, fh: {}, lock_owner: {:?})",
-            ino, fh, lock_owner
-        );
-        reply.error(ENOSYS);
-    }
-
-    fn release(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        _ino: u64,
-        _fh: u64,
-        _flags: i32,
-        _lock_owner: Option<u64>,
-        _flush: bool,
-        reply: fuser::ReplyEmpty,
-    ) {
-        reply.ok();
-    }
-
-    fn fsync(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        ino: u64,
-        fh: u64,
-        datasync: bool,
-        reply: fuser::ReplyEmpty,
-    ) {
-        debug!("[Not Implemented] fsync(ino: {:#x?}, fh: {}, datasync: {})", ino, fh, datasync);
-        reply.error(ENOSYS);
-    }
-
-    fn opendir(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        _ino: u64,
-        _flags: i32,
-        reply: fuser::ReplyOpen,
-    ) {
-        reply.opened(0, 0);
-    }
-
-    fn readdir(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        ino: u64,
-        fh: u64,
-        offset: i64,
-        reply: fuser::ReplyDirectory,
-    ) {
-        warn!("[Not Implemented] readdir(ino: {:#x?}, fh: {}, offset: {})", ino, fh, offset);
-        reply.error(ENOSYS);
-    }
-
-    fn readdirplus(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        ino: u64,
-        fh: u64,
-        offset: i64,
-        reply: fuser::ReplyDirectoryPlus,
-    ) {
-        debug!(
-            "[Not Implemented] readdirplus(ino: {:#x?}, fh: {}, offset: {})",
-            ino, fh, offset
-        );
-        reply.error(ENOSYS);
-    }
-
-    fn releasedir(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        _ino: u64,
-        _fh: u64,
-        _flags: i32,
-        reply: fuser::ReplyEmpty,
-    ) {
-        reply.ok();
-    }
-
-    fn fsyncdir(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        ino: u64,
-        fh: u64,
-        datasync: bool,
-        reply: fuser::ReplyEmpty,
-    ) {
-        debug!(
-            "[Not Implemented] fsyncdir(ino: {:#x?}, fh: {}, datasync: {})",
-            ino, fh, datasync
-        );
-        reply.error(ENOSYS);
-    }
-
-    fn statfs(&mut self, _req: &fuser::Request<'_>, _ino: u64, reply: fuser::ReplyStatfs) {
-        reply.statfs(0, 0, 0, 0, 0, 512, 255, 0);
-    }
-
-    fn setxattr(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        ino: u64,
-        name: &std::ffi::OsStr,
-        _value: &[u8],
-        flags: i32,
-        position: u32,
-        reply: fuser::ReplyEmpty,
-    ) {
-        debug!(
-            "[Not Implemented] setxattr(ino: {:#x?}, name: {:?}, flags: {:#x?}, position: {})",
-            ino, name, flags, position
-        );
-        reply.error(ENOSYS);
-    }
-
-    fn getxattr(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        ino: u64,
-        name: &std::ffi::OsStr,
-        size: u32,
-        reply: fuser::ReplyXattr,
-    ) {
-        debug!("[Not Implemented] getxattr(ino: {:#x?}, name: {:?}, size: {})", ino, name, size);
-        reply.error(ENOSYS);
-    }
-
-    fn listxattr(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        ino: u64,
-        size: u32,
-        reply: fuser::ReplyXattr,
-    ) {
-        debug!("[Not Implemented] listxattr(ino: {:#x?}, size: {})", ino, size);
-        reply.error(ENOSYS);
-    }
-
-    fn removexattr(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        ino: u64,
-        name: &std::ffi::OsStr,
-        reply: fuser::ReplyEmpty,
-    ) {
-        debug!("[Not Implemented] removexattr(ino: {:#x?}, name: {:?})", ino, name);
-        reply.error(ENOSYS);
-    }
-
-    fn access(&mut self, _req: &fuser::Request<'_>, ino: u64, mask: i32, reply: fuser::ReplyEmpty) {
-        debug!("[Not Implemented] access(ino: {:#x?}, mask: {})", ino, mask);
-        reply.error(ENOSYS);
-    }
-
-    fn create(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        parent: u64,
-        name: &std::ffi::OsStr,
-        mode: u32,
-        umask: u32,
-        flags: i32,
-        reply: fuser::ReplyCreate,
-    ) {
-        debug!(
-            "[Not Implemented] create(parent: {:#x?}, name: {:?}, mode: {}, umask: {:#x?}, \
-            flags: {:#x?})",
-            parent, name, mode, umask, flags
-        );
-        reply.error(ENOSYS);
-    }
-
-    fn getlk(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        ino: u64,
-        fh: u64,
-        lock_owner: u64,
-        start: u64,
-        end: u64,
-        typ: i32,
-        pid: u32,
-        reply: fuser::ReplyLock,
-    ) {
-        debug!(
-            "[Not Implemented] getlk(ino: {:#x?}, fh: {}, lock_owner: {}, start: {}, \
-            end: {}, typ: {}, pid: {})",
-            ino, fh, lock_owner, start, end, typ, pid
-        );
-        reply.error(ENOSYS);
-    }
-
-    fn setlk(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        ino: u64,
-        fh: u64,
-        lock_owner: u64,
-        start: u64,
-        end: u64,
-        typ: i32,
-        pid: u32,
-        sleep: bool,
-        reply: fuser::ReplyEmpty,
-    ) {
-        debug!(
-            "[Not Implemented] setlk(ino: {:#x?}, fh: {}, lock_owner: {}, start: {}, \
-            end: {}, typ: {}, pid: {}, sleep: {})",
-            ino, fh, lock_owner, start, end, typ, pid, sleep
-        );
-        reply.error(ENOSYS);
-    }
-
-    fn bmap(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        ino: u64,
-        blocksize: u32,
-        idx: u64,
-        reply: fuser::ReplyBmap,
-    ) {
-        debug!(
-            "[Not Implemented] bmap(ino: {:#x?}, blocksize: {}, idx: {})",
-            ino, blocksize, idx,
-        );
-        reply.error(ENOSYS);
-    }
-
-    fn ioctl(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        ino: u64,
-        fh: u64,
-        flags: u32,
-        cmd: u32,
-        in_data: &[u8],
-        out_size: u32,
-        reply: fuser::ReplyIoctl,
-    ) {
-        debug!(
-            "[Not Implemented] ioctl(ino: {:#x?}, fh: {}, flags: {}, cmd: {}, \
-            in_data.len(): {}, out_size: {})",
-            ino,
-            fh,
-            flags,
-            cmd,
-            in_data.len(),
-            out_size,
-        );
-        reply.error(ENOSYS);
-    }
-
-    fn fallocate(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        ino: u64,
-        fh: u64,
-        offset: i64,
-        length: i64,
-        mode: i32,
-        reply: fuser::ReplyEmpty,
-    ) {
-        debug!(
-            "[Not Implemented] fallocate(ino: {:#x?}, fh: {}, offset: {}, \
-            length: {}, mode: {})",
-            ino, fh, offset, length, mode
-        );
-        reply.error(ENOSYS);
-    }
-
-    fn lseek(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        ino: u64,
-        fh: u64,
-        offset: i64,
-        whence: i32,
-        reply: fuser::ReplyLseek,
-    ) {
-        debug!(
-            "[Not Implemented] lseek(ino: {:#x?}, fh: {}, offset: {}, whence: {})",
-            ino, fh, offset, whence
-        );
-        reply.error(ENOSYS);
-    }
-
-    fn copy_file_range(
-        &mut self,
-        _req: &fuser::Request<'_>,
-        ino_in: u64,
-        fh_in: u64,
-        offset_in: i64,
-        ino_out: u64,
-        fh_out: u64,
-        offset_out: i64,
-        len: u64,
-        flags: u32,
-        reply: fuser::ReplyWrite,
-    ) {
-        debug!(
-            "[Not Implemented] copy_file_range(ino_in: {:#x?}, fh_in: {}, \
-            offset_in: {}, ino_out: {:#x?}, fh_out: {}, offset_out: {}, \
-            len: {}, flags: {})",
-            ino_in, fh_in, offset_in, ino_out, fh_out, offset_out, len, flags
-        );
-        reply.error(ENOSYS);
+    fn get_inode_mut(&mut self, ino: u64) -> Option<&mut Inode> {
+        self.inode_table.get_mut(&ino)
     }
 }