feat(fusedev): add try_with_writer on FuseSession; update

[xujihui1985]

with_writer docs

• Introduce try_with_writer<F, R, E> that builds a FuseDevWriter and returns
  the closure’s Result, converting super::Error via From.
  • Return SessionFailure("invalid fuse session") when self.file is absent.
  • Tweak with_writer doc to clarify it passes a writer to the given closure.

example(passthrough): update example to show how to use try_with_writer

[sidneychang]

Hello, could you also provide the same implementation in macos_session?
Without it, the macOS build in nydus CI will fail since the implementation cannot be found during compilation.

[xujihui1985]

Hello, could you also provide the same implementation in macos_session? Without it, the macOS build in nydus CI will fail since the implementation cannot be found during compilation.

I didn't notice failed ci on macos, could you point out the failed test?

[sidneychang]

Hello, could you also provide the same implementation in macos_session? Without it, the macOS build in nydus CI will fail since the implementation cannot be found during compilation.

I didn't notice failed ci on macos, could you point out the failed test?

I noticed that this submission was originally prepared for the nydus PR #1740. In the original nydus code, the with_writer method was not used, which is why the macOS CI did not report any errors.

I tried to use the with_writer method in a PR, but in macos_session this method does not exist, causing nydus macos build CI fail. Here’s the error message I encountered:

error[E0599]: no method named `with_writer` found for struct `MutexGuard<'_, FuseSession>` in the current scope
   --> service/src/fusedev.rs:277:50
    |
277 |                     self.session.lock().unwrap().with_writer(|writer| {
    |                     -----------------------------^^^^^^^^^^^ method not found in `MutexGuard<'_, FuseSession>`

error[E0599]: no method named `with_writer` found for struct `MutexGuard<'_, FuseSession>` in the current scope
   --> service/src/fusedev.rs:286:46
    |
286 |                 self.session.lock().unwrap().with_writer(|writer| {
    |                 -----------------------------^^^^^^^^^^^ method not found in `MutexGuard<'_, FuseSession>`

If PR #1740 were to use try_with_writer, I think it would encounter the same issue. You can also see the CI run here: CI run link
.

[xujihui1985]

oh I see, thanks for point out the problem

[xujihui1985]

Hello, could you also provide the same implementation in macos_session? Without it, the macOS build in nydus CI will fail since the implementation cannot be found during compilation.

I didn't notice failed ci on macos, could you point out the failed test?

I noticed that this submission was originally prepared for the nydus PR #1740. In the original nydus code, the with_writer method was not used, which is why the macOS CI did not report any errors.

I tried to use the with_writer method in a PR, but in macos_session this method does not exist, causing nydus macos build CI fail. Here’s the error message I encountered:

error[E0599]: no method named `with_writer` found for struct `MutexGuard<'_, FuseSession>` in the current scope
   --> service/src/fusedev.rs:277:50
    |
277 |                     self.session.lock().unwrap().with_writer(|writer| {
    |                     -----------------------------^^^^^^^^^^^ method not found in `MutexGuard<'_, FuseSession>`

error[E0599]: no method named `with_writer` found for struct `MutexGuard<'_, FuseSession>` in the current scope
   --> service/src/fusedev.rs:286:46
    |
286 |                 self.session.lock().unwrap().with_writer(|writer| {
    |                 -----------------------------^^^^^^^^^^^ method not found in `MutexGuard<'_, FuseSession>`

If PR #1740 were to use try_with_writer, I think it would encounter the same issue. You can also see the CI run here: CI run link .

Hi I have implement the method for macos in the latest commit

[imeoer]

LGTM!