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>

2 files changed, 19 insertions, 4 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
diff --git a/src/network/ssl/qsslsocket_openssl_symbols.cpp b/src/network/ssl/qsslsocket_openssl_symbols.cpp
index 6ba8ba9db0..1756333371 100644
--- a/src/network/ssl/qsslsocket_openssl_symbols.cpp
+++ b/src/network/ssl/qsslsocket_openssl_symbols.cpp
@@ -68,6 +68,7 @@
 #include <QtCore/qdir.h>
 #endif
 #include <QtCore/private/qmemory_p.h>
+#include <QtCore/private/qduplicatetracker_p.h>
 #if defined(Q_OS_LINUX) && !defined(Q_OS_ANDROID)
 #include <link.h>
 #endif
@@ -569,13 +570,13 @@ static int dlIterateCallback(struct dl_phdr_info *info, size_t size, void *data)
 {
     if (size < sizeof (info->dlpi_addr) + sizeof (info->dlpi_name))
         return 1;
-    QSet<QString> *paths = (QSet<QString> *)data;
+    QDuplicateTracker<QString> *paths = (QDuplicateTracker<QString> *)data;
     QString path = QString::fromLocal8Bit(info->dlpi_name);
     if (!path.isEmpty()) {
         QFileInfo fi(path);
         path = fi.absolutePath();
         if (!path.isEmpty())
-            paths->insert(path);
+            (void)paths->hasSeen(std::move(path));
     }
     return 0;
 }
@@ -608,9 +609,9 @@ static QStringList libraryPathList()
     paths << QLatin1String("/system/lib");
 #elif defined(Q_OS_LINUX)
     // discover paths of already loaded libraries
-    QSet<QString> loadedPaths;
+    QDuplicateTracker<QString> loadedPaths;
     dl_iterate_phdr(dlIterateCallback, &loadedPaths);
-    paths.append(loadedPaths.values());
+    std::move(loadedPaths).appendTo(paths);
 #endif
 
     return paths;