Example showing shared linear memory use about wasmi HOT 10 CLOSED

Ok I'll see what I can come up with. Thanks again :)

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Unfortunately, I can't provide an example that focused on precisely this.

You can take a look on this test.

The basic idea is similar to the JS example. Just return a memory instance when the module imports it, still retaining a reference to it.

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Okay I'll take a look at those tests and see if I can duplicate the sample. I didn't know that resolve_memory was a thing, so this definitely gets me closer. Thanks!

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What I am struggling with is the demo I linked to shows using a pointer directly as a parameter in the function and doesn't seem to be using the linear memory directly ... like there's some macro magic at play that I can't see.

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No, you right : ) There is no magic because there is no usage of linear memory in the example (because of this I warned you that I can't provide a good example).

I think then better to start with TestHost example. It has a reference to a MemoryInstance. Test host uses the MemoryInstance to implement functions inc_mem and get_mem in it's Externals implementation.

But, unlike the previous example, TestHost doesn't export a memory instance. To actually make it export a memory instance, we can simply use the construction like in the previous example

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Whenever I create a Rust lib and put wasm_import_memory at the top, the resulting wasm produced by the compiler still appears to export memory... I don't see a

(import "env" "memory" (memory (;0;) 17))

line like the demos show from the link above.

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Ah, yeah. Try to add #![wasm_import_memory] attribute to the lib.rs of your project.

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I do.. my memory is still in an export section at the very bottom of the wat file after I convert it.

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I've figured a little bit out... I can access the exported memory with export_by_name. What I'm trying to figure out is how to invoke a function like the one from the SHA1 demo where the digest function returns a string.

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I was struggling to find good examples of doing this also....so empathise!

It's not using an imported linear memory (it's using one created internally, that you specify on getting Module, and then get via export) but this repo of mine trying to figure out the same thing maybe useful to you:

https://github.com/andrewdavidmackenzie/wasmi-string

For my project I don't want to pass/get Strings, but a more complex signature & return, so I advanced that a bit (using serde to serialize/deserialize - which suits my project) and pass anything that can be expressed in Serde to/from a function in the wasm module):

https://github.com/andrewdavidmackenzie/wasm_explore

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