45ff2fe12f
This prepares for exposing operations like Memory.Grow while keeping the ability to trace what did that, by adding a `context.Context` initial parameter. This adds this to all API methods that mutate or return mutated data. Before, we made a change to trace functions and general lifecycle commands, but we missed this part. Ex. We track functions, but can't track what closed the module, changed memory or a mutable constant. Changing to do this now is not only more consistent, but helps us optimize at least the interpreter to help users identify otherwise opaque code that can cause harm. This is critical before we add more functions that can cause harm, such as Memory.Grow. Signed-off-by: Adrian Cole <adrian@tetrate.io>
48 lines
1.1 KiB
Go
48 lines
1.1 KiB
Go
package wazero
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import (
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"context"
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_ "embed"
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"fmt"
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"log"
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)
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// This is an example of how to use WebAssembly via adding two numbers.
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//
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// See https://github.com/tetratelabs/wazero/tree/main/examples for more examples.
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func Example() {
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// Choose the context to use for function calls.
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ctx := context.Background()
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// Create a new WebAssembly Runtime.
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r := NewRuntime()
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// Add a module to the runtime named "wasm/math" which exports one function "add", implemented in WebAssembly.
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mod, err := r.InstantiateModuleFromCode(ctx, []byte(`(module $wasm/math
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(func $add (param i32 i32) (result i32)
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local.get 0
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local.get 1
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i32.add
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)
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(export "add" (func $add))
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)`))
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if err != nil {
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log.Fatal(err)
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}
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defer mod.Close(ctx)
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// Get a function that can be reused until its module is closed:
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add := mod.ExportedFunction("add")
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x, y := uint64(1), uint64(2)
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results, err := add.Call(ctx, x, y)
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if err != nil {
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log.Fatal(err)
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}
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fmt.Printf("%s: %d + %d = %d\n", mod.Name(), x, y, results[0])
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// Output:
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// wasm/math: 1 + 2 = 3
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}
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