Backend

public protocol Backend

The type that handles hooking of methods and functions.

Unless you have specific requirements, you should be able to use one of the pre-defined backends declared on Backends.

If you are creating a custom Backend implementation which is intended for distribution, declare it as a nested type in an extension on the Backends enumeration. The backend’s name is then the type name minus the Backends. prefix.

If a custom backend name is specified via the Orion CLI, Orion will automatically attempt to import a module named OrionBackend_<backend name> if it exists, so it is recommended that you follow this nomenclature while naming your framework. Note that when determining the framework name, any generic arguments are stripped from the type name, and only the first component of the name is used.

For example, a backend with the type Backends.Foo.Bar<Int> will be referred to by the name Foo.Bar<Int>, and Orion will attempt to auto-import a module named OrionBackend_Foo.

For more information on backends, consult the Orion CLI documentation.

  • Hooks the provided functions and methods.

    Declaration

    Swift

    func apply(hooks: [HookDescriptor])

    Parameters

    hooks

    The descriptors for the hooks to be applied.

  • hookFunction(_:replacement:) Extension method

    Performs a one-off function hook.

    Prefer batching with apply(hooks:) if you have multiple hooks, as backends may be able to optimize batch hooking.

    Declaration

    Swift

    public func hookFunction(_ function: Function, replacement: UnsafeMutableRawPointer) -> UnsafeMutableRawPointer

    Parameters

    function

    The function which is to be hooked.

    replacement

    The replacement function implementation. See HookDescriptor.function(function:replacement:completion:) for details.

    Return Value

    The original function implementation.

  • Performs a one-off method hook.

    Prefer batching with apply(hooks:) if you have multiple hooks, as backends may be able to optimize batch hooking.

    Declaration

    Swift

    public func hookMethod(cls: AnyClass, sel: Selector, replacement: UnsafeMutableRawPointer) -> UnsafeMutableRawPointer

    Parameters

    cls

    The class which contains the method to be hooked.

    sel

    The selector of the method to be hooked.

    replacement

    The replacement method implementation. See HookDescriptor.method(cls:sel:replacement:completion:) for details.

    Return Value

    The original method implementation.