QSsl: port a local QStringList to QDuplicateTracker

Apart from a more fitting, minimal, API, QDuplicateTracker also
transparently uses C++17 pmr::monotonic_buffer_resource to avoid, or
at least reduce, memory allocations.

The code is the first user of the collected data, so make that
available by adding QDuplicateTracker::appendTo(Container&) methods.

Change-Id: Ibd8810c0070db7e6b3ead6d6a569facdab88b646
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>

1 files changed, 14 insertions, 0 deletions

diff --git a/src/corelib/tools/qduplicatetracker_p.h b/src/corelib/tools/qduplicatetracker_p.h
index cd57d4aed5..baf21bfd12 100644
--- a/src/corelib/tools/qduplicatetracker_p.h
+++ b/src/corelib/tools/qduplicatetracker_p.h
@@ -99,6 +99,20 @@ public:
 #endif
         return !inserted;
     }
+
+    template <typename C>
+    void appendTo(C &c) const &
+    {
+        for (const auto &e : set)
+            c.push_back(e);
+    }
+
+    template <typename C>
+    void appendTo(C &c) &&
+    {
+        for (auto &e : set)
+            c.push_back(std::move(e));
+    }
 };
 
 QT_END_NAMESPACE