Use RefPtr as SafePtr backend

5 files changed, 71 insertions, 112 deletions

diff --git a/src/buffer_manager.cc b/src/buffer_manager.cc
index 74cacdb2..db3e37c5 100644
--- a/src/buffer_manager.cc
+++ b/src/buffer_manager.cc
@@ -36,7 +36,7 @@ void BufferManager::unregister_buffer(Buffer& buffer)
 {
     for (auto it = m_buffers.begin(); it != m_buffers.end(); ++it)
     {
-        if (*it == &buffer)
+        if (it->get() == &buffer)
         {
             m_buffers.erase(it);
             return;
@@ -44,7 +44,7 @@ void BufferManager::unregister_buffer(Buffer& buffer)
     }
     for (auto it = m_buffer_trash.begin(); it != m_buffer_trash.end(); ++it)
     {
-        if (*it == &buffer)
+        if (it->get() == &buffer)
         {
             m_buffer_trash.erase(it);
             return;
@@ -57,7 +57,7 @@ void BufferManager::delete_buffer(Buffer& buffer)
 {
     for (auto it = m_buffers.begin(); it != m_buffers.end(); ++it)
     {
-        if (*it == &buffer)
+        if (it->get() == &buffer)
         {
             if (ClientManager::has_instance())
                 ClientManager::instance().ensure_no_client_uses_buffer(buffer);
@@ -98,7 +98,8 @@ Buffer& BufferManager::get_buffer(StringView name)
 
 void BufferManager::set_last_used_buffer(Buffer& buffer)
 {
-    auto it = find(m_buffers, &buffer);
+    auto it = find_if(m_buffers, [&buffer](const SafePtr<Buffer>& p)
+                                 { return p.get() == &buffer; });
     kak_assert(it != m_buffers.end());
     m_buffers.erase(it);
     m_buffers.emplace(m_buffers.begin(), &buffer);
diff --git a/src/client_manager.cc b/src/client_manager.cc
index f1da3159..b1b97888 100644
--- a/src/client_manager.cc
+++ b/src/client_manager.cc
@@ -121,7 +121,7 @@ void ClientManager::ensure_no_client_uses_buffer(Buffer& buffer)
         // access, this selects a sensible buffer to display.
         for (auto& buf : BufferManager::instance())
         {
-            if (buf != &buffer)
+            if (buf.get() != &buffer)
             {
                client->context().change_buffer(*buf);
                break;
diff --git a/src/ref_ptr.hh b/src/ref_ptr.hh
index 09ec1f48..792e765c 100644
--- a/src/ref_ptr.hh
+++ b/src/ref_ptr.hh
@@ -1,17 +1,26 @@
 #ifndef ref_ptr_hh_INCLUDED
 #define ref_ptr_hh_INCLUDED
 
+#include <utility>
+
 namespace Kakoune
 {
 
-template<typename T>
+struct WorstMatch { [[gnu::always_inline]] WorstMatch(...) {} };
+
+[[gnu::always_inline]]
+inline void ref_ptr_moved(WorstMatch, void*, void*) noexcept {}
+
+template<typename T, typename TForOverload = T>
 struct RefPtr
 {
     RefPtr() = default;
-    RefPtr(T* ptr) : m_ptr(ptr) { acquire(); }
+    explicit RefPtr(T* ptr) : m_ptr(ptr) { acquire(); }
     ~RefPtr() { release(); }
     RefPtr(const RefPtr& other) : m_ptr(other.m_ptr) { acquire(); }
-    RefPtr(RefPtr&& other) : m_ptr(other.m_ptr) { other.m_ptr = nullptr; }
+    RefPtr(RefPtr&& other)
+        noexcept(noexcept(std::declval<RefPtr>().moved(nullptr)))
+        : m_ptr(other.m_ptr) { other.m_ptr = nullptr; moved(&other); }
 
     RefPtr& operator=(const RefPtr& other)
     {
@@ -25,6 +34,7 @@ struct RefPtr
         release();
         m_ptr = other.m_ptr;
         other.m_ptr = nullptr;
+        moved(&other);
         return *this;
     }
 
@@ -33,31 +43,42 @@ struct RefPtr
 
     T* get() const { return m_ptr; }
 
-    explicit operator bool() { return m_ptr; }
+    explicit operator bool() const { return m_ptr; }
 
-    friend bool operator==(const RefPtr& lhs, const RefPtr& rhs)
+    void reset(T* ptr = nullptr)
     {
-        return lhs.m_ptr == rhs.m_ptr;
-    }
-    friend bool operator!=(const RefPtr& lhs, const RefPtr& rhs)
-    {
-        return lhs.m_ptr != rhs.m_ptr;
+        if (ptr == m_ptr)
+            return;
+        release();
+        m_ptr = ptr;
+        acquire();
     }
+
+    friend bool operator==(const RefPtr& lhs, const RefPtr& rhs) { return lhs.m_ptr == rhs.m_ptr; }
+    friend bool operator!=(const RefPtr& lhs, const RefPtr& rhs) { return lhs.m_ptr != rhs.m_ptr; }
+
 private:
     T* m_ptr = nullptr;
 
     void acquire()
     {
         if (m_ptr)
-            inc_ref_count(m_ptr);
+            inc_ref_count(static_cast<TForOverload*>(m_ptr), this);
     }
 
     void release()
     {
         if (m_ptr)
-            dec_ref_count(m_ptr);
+            dec_ref_count(static_cast<TForOverload*>(m_ptr), this);
         m_ptr = nullptr;
-    } 
+    }
+
+    void moved(void* from)
+        noexcept(noexcept(ref_ptr_moved(static_cast<TForOverload*>(nullptr), nullptr, nullptr)))
+    {
+        if (m_ptr)
+            ref_ptr_moved(static_cast<TForOverload*>(m_ptr), from, this);
+    }
 };
 
 }
diff --git a/src/safe_ptr.hh b/src/safe_ptr.hh
index 6366bd13..2e3b3d2b 100644
--- a/src/safe_ptr.hh
+++ b/src/safe_ptr.hh
@@ -4,6 +4,10 @@
 // #define SAFE_PTR_TRACK_CALLSTACKS
 
 #include "assert.hh"
+#include "ref_ptr.hh"
+
+#include <type_traits>
+#include <utility>
 
 #ifdef SAFE_PTR_TRACK_CALLSTACKS
 #include "vector.hh"
@@ -15,84 +19,6 @@ namespace Kakoune
 
 // *** SafePtr: objects that assert nobody references them when they die ***
 
-template<typename T>
-class SafePtr
-{
-public:
-    SafePtr() : m_ptr(nullptr) {}
-    explicit SafePtr(T* ptr) : m_ptr(ptr)
-    {
-        #ifdef KAK_DEBUG
-        if (m_ptr)
-            m_ptr->inc_safe_count(this);
-        #endif
-    }
-    SafePtr(const SafePtr& other) : SafePtr(other.m_ptr) {}
-    SafePtr(SafePtr&& other) noexcept : m_ptr(other.m_ptr)
-    {
-        other.m_ptr = nullptr;
-        #ifdef KAK_DEBUG
-        if (m_ptr)
-            m_ptr->safe_ptr_moved(&other, this);
-        #endif
-    }
-    ~SafePtr()
-    {
-        #ifdef KAK_DEBUG
-        if (m_ptr)
-            m_ptr->dec_safe_count(this);
-        #endif
-    }
-
-    SafePtr& operator=(const SafePtr& other)
-    {
-        #ifdef KAK_DEBUG
-        if (m_ptr != other.m_ptr)
-        {
-            if (m_ptr)
-                m_ptr->dec_safe_count(this);
-            if (other.m_ptr)
-                other.m_ptr->inc_safe_count(this);
-        }
-        #endif
-        m_ptr = other.m_ptr;
-        return *this;
-    }
-
-    SafePtr& operator=(SafePtr&& other) noexcept
-    {
-        #ifdef KAK_DEBUG
-        if (m_ptr)
-            m_ptr->dec_safe_count(this);
-        if (other.m_ptr)
-            other.m_ptr->safe_ptr_moved(&other, this);
-        #endif
-        m_ptr = other.m_ptr;
-        other.m_ptr = nullptr;
-        return *this;
-    }
-
-    void reset(T* ptr = nullptr)
-    {
-        *this = SafePtr(ptr);
-    }
-
-    bool operator== (const SafePtr& other) const { return m_ptr == other.m_ptr; }
-    bool operator!= (const SafePtr& other) const { return m_ptr != other.m_ptr; }
-    bool operator== (T* ptr) const { return m_ptr == ptr; }
-    bool operator!= (T* ptr) const { return m_ptr != ptr; }
-
-    T& operator*  () const { return *m_ptr; }
-    T* operator-> () const { return m_ptr; }
-
-    T* get() const { return m_ptr; }
-
-    explicit operator bool() const { return m_ptr; }
-
-private:
-    T* m_ptr;
-};
-
 class SafeCountable
 {
 public:
@@ -106,31 +32,32 @@ public:
         #endif
     }
 
-    void inc_safe_count(void* ptr) const
+    friend void inc_ref_count(const SafeCountable* sc, void* ptr)
     {
-        ++m_count;
+        ++sc->m_count;
         #ifdef SAFE_PTR_TRACK_CALLSTACKS
-        m_callstacks.emplace_back(ptr);
+        sc->m_callstacks.emplace_back(ptr);
         #endif
     }
-    void dec_safe_count(void* ptr) const
+
+    friend void dec_ref_count(const SafeCountable* sc, void* ptr)
     {
-        --m_count;
-        kak_assert(m_count >= 0);
+        --sc->m_count;
+        kak_assert(sc->m_count >= 0);
         #ifdef SAFE_PTR_TRACK_CALLSTACKS
-        auto it = std::find_if(m_callstacks.begin(), m_callstacks.end(),
+        auto it = std::find_if(sc->m_callstacks.begin(), sc->m_callstacks.end(),
                                [=](const Callstack& cs) { return cs.ptr == ptr; });
-        kak_assert(it != m_callstacks.end());
-        m_callstacks.erase(it);
+        kak_assert(it != sc->m_callstacks.end());
+        sc->m_callstacks.erase(it);
         #endif
     }
 
-    void safe_ptr_moved(void* from, void* to) const
+    friend void ref_ptr_moved(const SafeCountable* sc, void* from, void* to)
     {
         #ifdef SAFE_PTR_TRACK_CALLSTACKS
-        auto it = std::find_if(m_callstacks.begin(), m_callstacks.end(),
+        auto it = std::find_if(sc->m_callstacks.begin(), sc->m_callstacks.end(),
                                [=](const Callstack& cs) { return cs.ptr == from; });
-        kak_assert(it != m_callstacks.end());
+        kak_assert(it != sc->m_callstacks.end());
         it->ptr = to;
         #endif
     }
@@ -157,9 +84,19 @@ private:
     mutable Vector<Callstack> m_callstacks;
     #endif
     mutable int m_count;
+#else
+    [[gnu::always_inline]]
+    friend void inc_ref_count(const SafeCountable* sc, void* ptr) {}
+
+    [[gnu::always_inline]]
+    friend void dec_ref_count(const SafeCountable* sc, void* ptr) {}
 #endif
 };
 
+template<typename T> using SafePtr =
+    RefPtr<T, typename std::conditional<std::is_const<T>::value,
+                                        const SafeCountable, SafeCountable>::type>;
+
 }
 
 #endif // safe_ptr_hh_INCLUDED
diff --git a/src/shared_string.hh b/src/shared_string.hh
index a73f8dd2..8af9820c 100644
--- a/src/shared_string.hh
+++ b/src/shared_string.hh
@@ -21,7 +21,7 @@ struct StringStorage : UseMemoryDomain<MemoryDomain::SharedString>
     [[gnu::always_inline]]
     StringView strview() const { return {data(), length}; }
 
-    static StringStorage* create(StringView str, char back = 0)
+    static RefPtr<StringStorage> create(StringView str, char back = 0)
     {
         const int len = (int)str.length() + (back != 0 ? 1 : 0);
         void* ptr = StringStorage::operator new(sizeof(StringStorage) + len + 1);
@@ -32,7 +32,7 @@ struct StringStorage : UseMemoryDomain<MemoryDomain::SharedString>
         if (back != 0)
             res->data()[len-1] = back;
         res->data()[len] = 0;
-        return res;
+        return RefPtr<StringStorage>(res);
     }
 
     static void destroy(StringStorage* s)
@@ -40,8 +40,8 @@ struct StringStorage : UseMemoryDomain<MemoryDomain::SharedString>
         StringStorage::operator delete(s, sizeof(StringStorage) + s->length + 1);
     }
 
-    friend void inc_ref_count(StringStorage* s) { ++s->refcount; }
-    friend void dec_ref_count(StringStorage* s) { if (--s->refcount == 0) StringStorage::destroy(s); }
+    friend void inc_ref_count(StringStorage* s, void*) { ++s->refcount; }
+    friend void dec_ref_count(StringStorage* s, void*) { if (--s->refcount == 0) StringStorage::destroy(s); }
 };
 
 inline RefPtr<StringStorage> operator"" _ss(const char* ptr, size_t len)