Crate gear_sandbox

This crate provides means to instantiate and execute wasm modules.

It works even when the user of this library executes from inside the wasm VM. In this case the same VM is used for execution of both the sandbox owner and the sandboxed module, without compromising security and without the performance penalty of full wasm emulation inside wasm.

This is achieved by using bindings to the wasm VM, which are published by the host API. This API is thin and consists of only a handful functions. It contains functions for instantiating modules and executing them, but doesn’t contain functions for inspecting the module structure. The user of this library is supposed to read the wasm module.

When this crate is used in the std environment all these functions are implemented by directly calling the wasm VM.

Examples of possible use-cases for this library are not limited to the following:

• implementing program runtimes that use Wasm for contract code
• executing a wasm substrate runtime inside of a wasm parachain

Re-exports

• pub use self::embedded_executor as default_executor;
• pub use gear_sandbox_env as env;

Modules

• embedded_executor
  An embedded WASM executor utilizing wasmer.

Structs

• HostError
  Error error that can be returned from host function.

Enums

• Error
  Error that can occur while using this crate.
• GlobalsSetError
  Error that can occur while using this crate.
• ReturnValue
  Typed value that can be returned from a function.
• Value
  Values supported by Substrate on the boundary between host/Wasm.

Traits

• AsContextExt
  Sandbox context.
• IntoValue
  Something that can be converted into a wasm compatible Value.
• SandboxEnvironmentBuilder
  Struct that can be used for defining an environment for a sandboxed module.
• SandboxInstance
  Sandboxed instance of a wasm module.
• SandboxMemory
  Reference to a sandboxed linear memory, that will be used by the guest module.
• SandboxStore
  Sandbox store.
• TryFromValue
  Something that can may be created from a wasm Value.

Type Aliases

• HostFuncType
  Function pointer for specifying functions by the supervisor in EnvironmentDefinitionBuilder.