From 2fc03e4050182f91f7573659e409811f14103f2c Mon Sep 17 00:00:00 2001
From: Patrick Wuttke <mewin@mewin.de>
Date: Mon, 23 Jun 2025 00:21:46 +0200
Subject: [PATCH] Made Signal allocator-aware.

---
 source/mijin/async/signal.hpp | 43 +++++++++++++++++++++--------------
 1 file changed, 26 insertions(+), 17 deletions(-)

diff --git a/source/mijin/async/signal.hpp b/source/mijin/async/signal.hpp
index 632b65a..382f352 100644
--- a/source/mijin/async/signal.hpp
+++ b/source/mijin/async/signal.hpp
@@ -33,11 +33,11 @@ inline constexpr signal_token_t INVALID_SIGNAL_TOKEN = std::numeric_limits<signa
 
 MIJIN_DEFINE_FLAG(Oneshot);
 
-template<typename... TArgs>
-class Signal
+template<template<typename> typename TAllocator, typename... TArgs>
+class BaseSignal
 {
 public:
-    using handler_t = std::function<void(TArgs...)>;
+    using handler_t = std::function<void(TArgs...)>; // TODO: write a custom function wrapper with allocator support
     using token_t = signal_token_t;
 private:
     struct RegisteredHandler
@@ -47,18 +47,24 @@ private:
         token_t token;
         Oneshot oneshot = Oneshot::NO;
     };
-    using handler_vector_t = std::vector<RegisteredHandler>;
+    using handler_vector_t = std::vector<RegisteredHandler, TAllocator<RegisteredHandler>>;
 private:
     handler_vector_t handlers_;
     token_t nextToken = 1;
     std::mutex handlersMutex_;
 public:
-    Signal() = default;
-    Signal(const Signal&) = delete;
-    Signal(Signal&&) MIJIN_NOEXCEPT = default;
+    explicit BaseSignal(TAllocator<void> allocator = {}) : handlers_(TAllocator<RegisteredHandler>(std::move(allocator))) {}
+    BaseSignal(const BaseSignal&) = delete;
+    BaseSignal(BaseSignal&&) MIJIN_NOEXCEPT = default;
+
+    void reinit(TAllocator<void> allocator = {})
+    {
+        MIJIN_ASSERT(handlers_.empty(), "Attempting to re-initialize a signal that already has handlers.");
+        handlers_ = handler_vector_t(TAllocator<RegisteredHandler>(std::move(allocator)));
+    }
 public:
-    Signal& operator=(const Signal&) = delete;
-    Signal& operator=(Signal&&) MIJIN_NOEXCEPT = default;
+    BaseSignal& operator=(const BaseSignal&) = delete;
+    BaseSignal& operator=(BaseSignal&&) MIJIN_NOEXCEPT = default;
 public:
     template<typename THandler, typename TWeak = void>
     inline token_t connect(THandler handler, Oneshot oneshot = Oneshot::NO, std::weak_ptr<TWeak> referenced = std::weak_ptr<TWeak>()) MIJIN_NOEXCEPT;
@@ -70,13 +76,16 @@ public:
     inline void emit(TArgs2&&... args) MIJIN_NOEXCEPT;
 };
 
+template<typename... TArgs>
+using Signal = BaseSignal<MIJIN_DEFAULT_ALLOCATOR, TArgs...>;
+
 //
 // public functions
 //
 
-template<typename... TArgs>
+template<template<typename> typename TAllocator, typename... TArgs>
 template<typename THandler, typename TWeak>
-inline auto Signal<TArgs...>::connect(THandler handler, Oneshot oneshot, std::weak_ptr<TWeak> referenced) MIJIN_NOEXCEPT -> token_t
+inline auto BaseSignal<TAllocator, TArgs...>::connect(THandler handler, Oneshot oneshot, std::weak_ptr<TWeak> referenced) MIJIN_NOEXCEPT -> token_t
 {
     std::lock_guard lock(handlersMutex_);
 
@@ -91,9 +100,9 @@ inline auto Signal<TArgs...>::connect(THandler handler, Oneshot oneshot, std::we
     return nextToken++;
 }
 
-template<typename... TArgs>
+template<template<typename> typename TAllocator, typename... TArgs>
 template<typename TObject, typename TWeak>
-inline auto Signal<TArgs...>::connect(TObject& object, void (TObject::* handler)(TArgs...), Oneshot oneshot, std::weak_ptr<TWeak> referenced) MIJIN_NOEXCEPT -> token_t
+inline auto BaseSignal<TAllocator, TArgs...>::connect(TObject& object, void (TObject::* handler)(TArgs...), Oneshot oneshot, std::weak_ptr<TWeak> referenced) MIJIN_NOEXCEPT -> token_t
 {
     std::lock_guard lock(handlersMutex_);
 
@@ -111,8 +120,8 @@ inline auto Signal<TArgs...>::connect(TObject& object, void (TObject::* handler)
     return nextToken++;
 }
 
-template<typename... TArgs>
-inline void Signal<TArgs...>::disconnect(token_t token) MIJIN_NOEXCEPT
+template<template<typename> typename TAllocator, typename... TArgs>
+inline void BaseSignal<TAllocator, TArgs...>::disconnect(token_t token) MIJIN_NOEXCEPT
 {
     std::lock_guard lock(handlersMutex_);
 
@@ -123,9 +132,9 @@ inline void Signal<TArgs...>::disconnect(token_t token) MIJIN_NOEXCEPT
     handlers_.erase(it, handlers_.end());
 }
 
-template<typename... TArgs>
+template<template<typename> typename TAllocator, typename... TArgs>
 template<typename... TArgs2>
-inline void Signal<TArgs...>::emit(TArgs2&&... args) MIJIN_NOEXCEPT
+inline void BaseSignal<TAllocator, TArgs...>::emit(TArgs2&&... args) MIJIN_NOEXCEPT
 {
     std::lock_guard lock(handlersMutex_);