storage_proxy: make unique_response_handler friendly to small_vector

small_vector wants the move constructor to be noexcept, and move assighment to exist (and be noexcept). These are easy to achieve.
scylladb · May 9, 2021 · b015ded · b015ded
1 parent 8398510
commit b015ded
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Showing 2 changed files with 11 additions and 2 deletions.
diff --git a/service/storage_proxy.cc b/service/storage_proxy.cc
@@ -1811,7 +1811,15 @@ storage_proxy::storage_proxy(distributed<database>& db, storage_proxy::config cf
 }
 
 storage_proxy::unique_response_handler::unique_response_handler(storage_proxy& p_, response_id_type id_) : id(id_), p(p_) {}
-storage_proxy::unique_response_handler::unique_response_handler(unique_response_handler&& x) : id(x.id), p(x.p) { x.id = 0; };
+storage_proxy::unique_response_handler::unique_response_handler(unique_response_handler&& x) noexcept : id(x.id), p(x.p) { x.id = 0; };
+
+storage_proxy::unique_response_handler&
+storage_proxy::unique_response_handler::operator=(unique_response_handler&& x) noexcept {
+    // this->p must equal x.p
+    id = std::exchange(x.id, 0);
+    return *this;
+}
+
 storage_proxy::unique_response_handler::~unique_response_handler() {
     if (id) {
         p.remove_response_handler(id);

diff --git a/service/storage_proxy.hh b/service/storage_proxy.hh
@@ -194,7 +194,8 @@ private:
         unique_response_handler(storage_proxy& p_, response_id_type id_);
         unique_response_handler(const unique_response_handler&) = delete;
         unique_response_handler& operator=(const unique_response_handler&) = delete;
-        unique_response_handler(unique_response_handler&& x);
+        unique_response_handler(unique_response_handler&& x) noexcept;
+        unique_response_handler& operator=(unique_response_handler&&) noexcept;
         ~unique_response_handler();
         response_id_type release();
     };