Uno/Spec/Threading-Model

version: 12555
state: draft
type: specification

UNO Threading Model

Feature

The UNO Runtime provides support for implementing

• Thread Free, or
• Thread Safe, or
• Thread Unsafe, or
• Thread Affine

Code.

The threading type of any code can be specified appropriately. The Thread Unsafe type is the default type for any implementation.

Rationale

API

Purpose Environment

The different threading types are supported by using Purpose Environments.

Implementation Environment

The actual threading type can be selected in a Language Binding typical way and is backed by the appropriate Purpose Bridge. The used Purpose Bridges are the

• Thread Unsafety Bridge for Thread Unsafe code and the
• Thread Affinty Bridge for Thread Affine code. Thread Safe code does not need to be backed, as this is the default for plain code, these also preserves compatibility with previous UNO versions.

Code may as well be declared Thread Free, so that it may be used from any other kind of code.

Environment Stack

The current (purpose) environment does not only vary with the implementation language (e.g. Java or C++), but also with the executed codes declared threading type. An API for accessing the current environment is provided.

Cascaded Mapping

Purpose environments may be passed to the Runtime for accessing cascaded mappings ("gcc3" => "java:unsafe:debug").

Dependencies

• Uno/Spec/Thread Affinity Bridge
• Uno/Spec/Thread Unsafety Bridge
• Uno/Spec/Purpose Environment
• Uno/Spec/Environment Stack
• Uno/Spec/Implementation Environment
• Uno/Spec/Cascaded Mapping
• Uno/Spec/Environment Substitution