From 29410073010f61560735395593a22524385808ff Mon Sep 17 00:00:00 2001
From: mutouyun <orz@orzz.org>
Date: Sat, 29 Dec 2018 22:42:26 +0800
Subject: [PATCH] use pool_alloc instead of std::allocator

---
 include/rw_lock.h       |  7 ++++
 src/ipc.cpp             |  4 +--
 src/memory/alloc.hpp    | 29 -----------------
 src/memory/resource.hpp | 10 +++---
 src/memory/wrapper.hpp  | 71 +++++++++++++++++++++++++++++++----------
 5 files changed, 68 insertions(+), 53 deletions(-)

diff --git a/include/rw_lock.h b/include/rw_lock.h
index 7226c5c..49f1f6d 100644
--- a/include/rw_lock.h
+++ b/include/rw_lock.h
@@ -80,6 +80,13 @@ class rw_lock {
     };
 
 public:
+    rw_lock() = default;
+
+    rw_lock(const rw_lock&) = delete;
+    rw_lock& operator=(const rw_lock&) = delete;
+    rw_lock(rw_lock&&) = delete;
+    rw_lock& operator=(rw_lock&&) = delete;
+
     void lock() noexcept {
         for (unsigned k = 0;; ++k) {
             auto old = lc_.fetch_or(w_flag, std::memory_order_acquire);
diff --git a/src/ipc.cpp b/src/ipc.cpp
index 64188b2..4536569 100644
--- a/src/ipc.cpp
+++ b/src/ipc.cpp
@@ -60,8 +60,8 @@ template <typename T>
 using remove_cv_ref_t = std::remove_cv_t<std::remove_reference_t<T>>;
 
 template <typename Cache>
-constexpr auto to_buff(Cache&& cac) -> Requires<std::is_same<remove_cv_ref_t<Cache>, buff_t>::value, buff_t> {
-    return cac;
+constexpr auto to_buff(Cache&& cac) -> Requires<std::is_same<remove_cv_ref_t<Cache>, buff_t>::value, Cache&&> {
+    return std::forward<Cache>(cac);
 }
 
 template <typename Cache>
diff --git a/src/memory/alloc.hpp b/src/memory/alloc.hpp
index 9b125ce..b869a68 100644
--- a/src/memory/alloc.hpp
+++ b/src/memory/alloc.hpp
@@ -1,6 +1,5 @@
 #pragma once
 
-#include <limits>
 #include <algorithm>
 #include <utility>
 #include <cstdlib>
@@ -12,10 +11,6 @@ namespace mem {
 
 class static_alloc {
 public:
-    static constexpr std::size_t remain() {
-        return (std::numeric_limits<std::size_t>::max)();
-    }
-
     static constexpr void clear() {}
     static constexpr void swap(static_alloc&) {}
 
@@ -46,16 +41,6 @@ protected:
     block_t* list_ = nullptr;
 
 public:
-    std::size_t remain() const {
-        std::size_t c = 0;
-        auto curr = list_;
-        while (curr != nullptr) {
-            ++c;
-            curr = curr->next_;
-        }
-        return c;
-    }
-
     void free(void* /*p*/) {}
     void free(void* /*p*/, std::size_t) {}
 };
@@ -127,16 +112,6 @@ protected:
     }
 
 public:
-    std::size_t remain() const {
-        std::size_t c = 0;
-        void* curr = cursor_;
-        while (curr != nullptr) {
-            ++c;
-            curr = next(curr);
-        }
-        return c;
-    }
-
     void free(void* p) {
         if (p == nullptr) return;
         next(p) = cursor_;
@@ -188,10 +163,6 @@ public:
         std::swap(this->cursor_     , rhs.cursor_);
     }
 
-    std::size_t remain() const {
-        return detail::fixed_pool_base::remain() * block_size;
-    }
-
     void clear() {
         alloc_.clear();
         init(init_expand_);
diff --git a/src/memory/resource.hpp b/src/memory/resource.hpp
index fa87f93..152bcb9 100644
--- a/src/memory/resource.hpp
+++ b/src/memory/resource.hpp
@@ -10,8 +10,6 @@
 #include "memory/alloc.hpp"
 #include "memory/wrapper.hpp"
 
-#include "tls_pointer.h"
-
 namespace ipc {
 namespace mem {
 
@@ -34,8 +32,8 @@ class pool_alloc {
 private:
     template <std::size_t Size>
     static auto& fixed() {
-        static tls::pointer<fixed_pool<Size>> fp;
-        return *fp.create();
+        static synchronized<fixed_pool<Size>> pool;
+        return pool;
     }
 
     template <typename F>
@@ -83,11 +81,11 @@ using allocator = allocator_wrapper<T, pool_alloc>;
 
 template <typename Key, typename T>
 using unordered_map = std::unordered_map<
-    Key, T//, std::hash<Key>, std::equal_to<Key>, allocator<std::pair<const Key, T>>
+    Key, T, std::hash<Key>, std::equal_to<Key>, allocator<std::pair<const Key, T>>
 >;
 
 template <typename T>
-using vector = std::vector<T/*, allocator<T>*/>;
+using vector = std::vector<T, allocator<T>>;
 
 } // namespace mem
 } // namespace ipc
diff --git a/src/memory/wrapper.hpp b/src/memory/wrapper.hpp
index 69fb531..55eab36 100644
--- a/src/memory/wrapper.hpp
+++ b/src/memory/wrapper.hpp
@@ -4,8 +4,11 @@
 #include <new>
 #include <mutex>
 #include <shared_mutex>
-#include <vector>
+#include <tuple>
+#include <map>
+#include <functional>
 #include <utility>
+#include <cstddef>
 
 #include "rw_lock.h"
 #include "tls_pointer.h"
@@ -18,39 +21,75 @@ namespace mem {
 ////////////////////////////////////////////////////////////////
 
 template <typename AllocP>
-class synchronized_pool {
+class synchronized {
 public:
     using alloc_policy = AllocP;
 
 private:
     rw_lock lc_;
-    std::vector<alloc_policy*> allocs_;
+    std::multimap<std::size_t, alloc_policy*, std::greater<std::size_t>> allocs_;
 
     struct alloc_t {
-        synchronized_pool* t_;
-        alloc_policy* alc_;
+        synchronized* t_;
+        std::size_t   s_ = 0;
+        alloc_policy* a_ = nullptr;
 
-        alloc_t(synchronized_pool* t)
-            : t_ { t }
-        {}
+        alloc_t(synchronized* t)
+            : t_ { t } {
+            {
+                [[maybe_unused]] auto guard = std::unique_lock { t_->lc_ };
+                auto it = t_->allocs_.begin();
+                if (it != t_->allocs_.end()) {
+                    std::tie(s_, a_) = *it;
+                    t_->allocs_.erase(it);
+                }
+            }
+            if (a_ == nullptr) {
+                a_ = new alloc_policy;
+            }
+        }
 
         ~alloc_t() {
+            [[maybe_unused]] auto guard = std::unique_lock { t_->lc_ };
+            t_->allocs_.emplace(s_, a_);
+        }
 
+        void* alloc(std::size_t size) {
+            void* p = a_->alloc(size);
+            if ((p != nullptr) && (s_ > 0)) {
+                --s_;
+            }
+            return p;
+        }
+
+        void free(void* p) {
+            a_->free(p);
+            ++s_;
         }
     };
 
+    auto& alc_info() {
+        static tls::pointer<alloc_t> alc;
+        return *alc.create(this);
+    }
+
 public:
-    static constexpr std::size_t remain() {
-        return (std::numeric_limits<std::size_t>::max)();
+    ~synchronized() {
+        for (auto& pair : allocs_) {
+            delete pair.second;
+        }
     }
 
-    static void* alloc() {
-        static tls::pointer<alloc_policy> alc;
-        return nullptr;
+    void* alloc(std::size_t size) {
+        return alc_info().alloc(size);
     }
 
-    static void* alloc(std::size_t) {
-        return alloc();
+    void free(void* p) {
+        alc_info().free(p);
+    }
+
+    static void free(void* p, std::size_t /*size*/) {
+        free(p);
     }
 };
 
@@ -122,7 +161,7 @@ public:
         return static_cast<pointer>(alloc_.alloc(count * sizeof(T)));
     }
 
-    void deallocate(pointer p, size_type count) {
+    void deallocate(pointer p, size_type count) noexcept {
         alloc_.free(p, count * sizeof(T));
     }