v3.0.0 — Multi-threaded reuseport listener support, deferred frames, and improved timer API

Release notes:

This update introduces major runtime and coroutine improvements for uvent, enabling finer scheduling control, better scalability, and safer timer usage.

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🧩 Coroutine System

Deferred frame model

• Added deferred_task_tag and DeferredFrame concept.

• Coroutines can now start immediately or deferred depending on whether their frame inherits from deferred_task_tag.

  • Example: AwaitableIOFrame is now deferred by default — execution begins only when explicitly resumed (e.g. by an I/O event).
  • Regular AwaitableFrame coroutines still start immediately once enqueued.

• This mechanism unifies instant and event-driven coroutine behavior without runtime branching.

AwaitableFrameBase improvements

• Clearer coroutine chaining (prev_ / next_) and destruction semantics.
• Consistent push_frame_into_task_queue logic between deferred and active frames.
• Simplified and safer final suspend behavior.

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⚙️ Runtime & Scheduling

Per-thread scheduling API

• Added Uvent::for_each_thread(F&& fn) — iterate all worker threads before run().
  Enables per-thread initialization or static coroutine registration.
• Added system::co_spawn_static(F&& f, int threadIndex) — enqueue coroutines into a specific thread inbox before startup.
  Ideal for binding listeners or initializing thread-local resources.

SO_REUSEPORT optimization

• When UVENT_ENABLE_REUSEADDR is defined and supported by the platform,
  each worker thread can create its own TCP listener.
  Combined with for_each_thread, this enables true parallel accept loops and linear scalability across cores.

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⏱️ Timers

Timer API redesigned

• Updated addFunction signature to use std::any:

  void addFunction(std::function<void(std::any&)> f, std::any arg);
  void addFunction(std::function<void(std::any&)> f, std::any& arg);

  Simplifies type handling and supports arbitrary callback payloads.

• Added INTERVAL timers for periodic execution.

• Safer coroutine-based sleep_for() using internal TimerWheel.

• Updated docs with examples and warnings against use-after-free.

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🧵 Core fixes and enhancements

• Unified handling of thread-local storage registry (TLSRegistry) for consistent pre-start coroutine enqueue.

• Improved lifecycle management in coroutine destruction paths.

• Refined exception propagation and await_suspend behavior.

• Documentation rewritten for all affected modules:

  • Awaitable
  • AwaitableFrame
  • System Primitives
  • Timer API
  • Uvent (runtime entry)

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✅ Summary

This release introduces:

• Deferred coroutine execution model
• Per-thread listener scheduling via for_each_thread
• SO_REUSEPORT-based scalability
• New std::any-based timer callbacks
• Safer and more extensible coroutine lifecycle

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Recommended version: v3.0.0
Tag message:

Deferred coroutine frames, per-thread listeners, and enhanced timer API for high-performance multi-core scalability.