Callbacks between Wasm and Native code #670
Labels
🎉 enhancement
New feature!
Comments
|
I believe this is the same as or very similar to #638 ; Thanks for the report -- I agree that this is an important thing to be able to do! |
This was referenced Sep 16, 2019
bors bot
added a commit
that referenced
this issue
Sep 19, 2019
803: Add method to call function at index on Ctx r=MarkMcCaskey a=MarkMcCaskey For #638 and #670 ```Rust fn call_guest_fn(ctx: &mut Ctx, guest_fn: u32) -> u32 { println!("{}", guest_fn); let guest_fn_typed = unsafe { guest_fn }; let result = ctx.call_with_table_index(guest_fn_typed, &[]).unwrap(); println!(" -> {:?}", result); 0 } ``` is what this looks like from the Host side # Review - [x] Create a short description of the the change in the CHANGELOG.md file Co-authored-by: Mark McCaskey <[email protected]> Co-authored-by: Mark McCaskey <[email protected]>
|
I got this working in #803 with an example!! |
bors bot
added a commit
that referenced
this issue
Sep 19, 2019
803: Add method to call function at index on Ctx r=MarkMcCaskey a=MarkMcCaskey For #638 and #670 ```Rust fn call_guest_fn(ctx: &mut Ctx, guest_fn: u32) -> u32 { println!("{}", guest_fn); let guest_fn_typed = unsafe { std::mem::transmute(guest_fn) }; let result = ctx.call_with_table_index(guest_fn_typed, &[]).unwrap(); println!(" -> {:?}", result); 0 } ``` is what this looks like from the Host side See `examples/callback.rs` for an example that doesn't require `transmute` # Review - [x] Create a short description of the the change in the CHANGELOG.md file Co-authored-by: Mark McCaskey <[email protected]> Co-authored-by: Mark McCaskey <[email protected]>
|
Closing because #803 merged in. If you have any issues, don't hesitate to reopen this issue or file a new one! |
|
This weekend I'll have time to integrate this change into my project. I'll let you know how it goes! |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Motivation
I would like to use callbacks between Wasm and native code. I would like to implement a callback on the Wasm-side, pass it as an argument, and later invoke it from the native-side.
I basically want to do what's in this StackOverflow question, but with Wasmer and Rust.
Proposed solution
On the native-side, which is embedding the VM, I want to receive a pointer to a function implemented on the Wasm-side, and somehow lookup and dispatch that function. I would like to be able to do this without any shims or exported functions.
It might look something like this:
Additional context
I've attempted #245, but I haven't made any progress there. (Help please!)
I've implemented callbacks in my own demo project, but it required some pretty undesirable work-arounds, like a export function shim.
There was also some discussion on Spectrum.
The text was updated successfully, but these errors were encountered: