import quincy beta 17.1.0

[ceph.git] / ceph / src / seastar / include / seastar / core / weak_ptr.hh

diff --git a/ceph/src/seastar/include/seastar/core/weak_ptr.hh b/ceph/src/seastar/include/seastar/core/weak_ptr.hh
index 884ddb13e69e904ecb37a51e7b2988f69b3a2c04..08b4aa77e983ecbf1ff23d2debb64962a0b66843 100644 (file)
--- a/ceph/src/seastar/include/seastar/core/weak_ptr.hh
+++ b/ceph/src/seastar/include/seastar/core/weak_ptr.hh
@@ -46,6 +46,14 @@ private:
     hook_type _hook;
     T* _ptr = nullptr;
     weak_ptr(T* p) noexcept : _ptr(p) {}
+    void clear() noexcept {
+        _hook = {};
+        _ptr = nullptr;
+    }
+    void swap(weak_ptr&& o) noexcept {
+        _hook.swap_nodes(o._hook);
+        std::swap(_ptr, o._ptr);
+    }
 public:
     // Note: The default constructor's body is implemented as no-op
     // rather than `noexcept = default` due to a bug with gcc 9.3.1
@@ -54,15 +62,27 @@ public:
     weak_ptr() noexcept {}
     weak_ptr(std::nullptr_t) noexcept : weak_ptr() {}
     weak_ptr(weak_ptr&& o) noexcept
-        : _ptr(o._ptr)
     {
-        _hook.swap_nodes(o._hook);
-        o._ptr = nullptr;
+        swap(std::move(o));
+    }
+    weak_ptr(const weak_ptr& o) noexcept {
+        if (o._ptr) {
+            swap(o._ptr->weak_from_this());
+        }
     }
     weak_ptr& operator=(weak_ptr&& o) noexcept {
         if (this != &o) {
-            this->~weak_ptr();
-            new (this) weak_ptr(std::move(o));
+            clear();
+            swap(std::move(o));
+        }
+        return *this;
+    }
+    weak_ptr& operator=(const weak_ptr& o) noexcept {
+        if (this != &o) {
+            clear();
+            if (o._ptr) {
+                swap(o._ptr->weak_from_this());
+            }
         }
         return *this;
     }