hnes/libaco
Libaco
libaco is a low-level C library for cooperative multitasking that provides a runtime for managing asymmetric coroutines. It functions as an execution context manager and stack memory allocator, allowing a single process to initialize independent execution units with private stacks and perform manual context switching via yield operations.
The library distinguishes itself through its memory management and stability features, utilizing read-only guard pages at stack boundaries to trigger hardware faults upon stack overflow. It supports both private stack allocation and shared stack pooling to reduce memory overhead, and it provides configurable floating-point state isolation to maintain numerical precision during switches.
The system covers the full lifecycle of cooperative routines, including creation, state switching, and destruction. It includes error handling mechanisms that execute designated protector functions or callbacks when a routine terminates abnormally to ensure system stability and resource cleanup.
Features
- Cooperative Multitasking - Provides a runtime for cooperative multitasking where routines voluntarily yield control to a scheduler.
- C Context Switching Libraries - Provides low-level C primitives for rapid switching between execution states and private memory stacks.
- Execution Context Management - Initializes independent execution units with private stacks and configurable memory regions.
- Fine-Grained Task Switching - Implements low-level mechanisms for rapidly switching execution contexts between cooperative routines.
- Context Switching Implementations - Implements the low-level mechanism of swapping CPU execution states between different cooperative tasks.
- Stack Memory Management - Manages continuous memory regions for execution stacks, utilizing guard pages for overflow prevention.
- Stack Overflow Protections - Utilizes read-only guard pages at stack boundaries to trigger hardware faults upon stack overflow.
- Coroutine Lifecycle Management - Manages the full execution cycle of cooperative routines, from initialization to memory reclamation upon destruction.
- Coroutine Libraries - Provides a low-level C runtime for managing asymmetric coroutines and cooperative multitasking.
- Coroutines - Provides lightweight cooperative multitasking units that can be paused and resumed.
- Asymmetric - Implements a control flow where a main coordinator manages the execution and suspension of several worker routines.
- Coroutine Spawning - Initializes new cooperative execution units with specific entry functions and private stacks.
- Floating Point State Management - Provides mechanisms for saving and restoring floating point control words to maintain numerical precision during switches.
- Shared Stack Pools - Supports shared stack pooling to reduce memory overhead across multiple execution units.
- Embedded Task Schedulers - Creates lightweight execution units suitable for resource-constrained environments requiring efficient task switching.
- Stack-Copying Context Switches - Manages unit transitions by saving and restoring CPU registers during coroutine context switches.
- Shared Stack Pooling - Supports shared stack pooling to reduce total system memory overhead while maintaining overflow protection.
- Abnormal Termination Protectors - Executes a custom protector function when a routine terminates abnormally to ensure resource cleanup.
- Routine Protector Functions - Executes designated protector functions or callbacks when a routine terminates abnormally to ensure system stability.
- Windows Environments - Listed in the “Windows Environments” section of the Awesome C awesome list.
