Split QAbstractFileEngine::create

The new, ugly-named resolveEntryAndCreateLegacyEngine will never
instantiate QFSFileEngine and uses the QFileSystemEngine API to check if
files exist, when necessary.

This way, we reduce allocations of QFSFileEngine when resolving paths.
Clients of the QAbstractFileEngine API will be able to opt-out of using
QFSFileEngine altogether.

Reviewed-by: Thomas Zander

1 files changed, 13 insertions, 41 deletions

diff --git a/src/corelib/io/qabstractfileengine.cpp b/src/corelib/io/qabstractfileengine.cpp
index e055e7bf1c..67109aa02b 100644
--- a/src/corelib/io/qabstractfileengine.cpp
+++ b/src/corelib/io/qabstractfileengine.cpp
@@ -52,6 +52,10 @@
 #include "qdiriterator.h"
 #include "qstringbuilder.h"
 
+#include <QtCore/private/qfilesystementry_p.h>
+#include <QtCore/private/qfilesystemmetadata_p.h>
+#include <QtCore/private/qfilesystemengine_p.h>
+
 QT_BEGIN_NAMESPACE
 
 /*!
@@ -200,49 +204,17 @@ QAbstractFileEngine *qt_custom_file_engine_handler_create(const QString &path)
 */
 QAbstractFileEngine *QAbstractFileEngine::create(const QString &fileName)
 {
-    if (QAbstractFileEngine *engine = qt_custom_file_engine_handler_create(filePath))
-        return engine;
-
-#ifdef QT_BUILD_CORE_LIB
-    for (int prefixSeparator = 0; prefixSeparator < fileName.size(); ++prefixSeparator) {
-        QChar const ch = fileName[prefixSeparator];
-        if (ch == QLatin1Char('/'))
-            break;
-
-        if (ch == QLatin1Char(':')) {
-            if (prefixSeparator == 0)
-                return new QResourceFileEngine(fileName);
-
-            if (prefixSeparator == 1)
-                break;
-
-            const QStringList &paths = QDir::searchPaths(fileName.left(prefixSeparator));
-            for (int i = 0; i < paths.count(); i++) {
-                QAbstractFileEngine *engine = create(paths.at(i) % QLatin1Char('/') % fileName.mid(prefixSeparator + 1));
-                if (engine && (engine->fileFlags(QAbstractFileEngine::FlagsMask) & QAbstractFileEngine::ExistsFlag)) {
-                    return engine;
-                }
-                delete engine;
-            }
-
-            break;
-        }
-
-        //  There's no need to fully validate the prefix here. Consulting the
-        //  unicode tables could be expensive and validation is already
-        //  performed in QDir::setSearchPaths.
-        //
-        //  if (!ch.isLetterOrNumber())
-        //      break;
-    }
+    QFileSystemEntry entry(fileName);
+    QFileSystemMetaData metaData;
+    QAbstractFileEngine *engine = QFileSystemEngine::resolveEntryAndCreateLegacyEngine(entry, metaData);
+
+#ifndef QT_NO_FSFILEENGINE
+    if (!engine)
+        // fall back to regular file engine
+        return new QFSFileEngine(entry.filePath());
 #endif
 
-#ifdef QT_NO_FSFILEENGINE
-    return 0;
-#else
-    // fall back to regular file engine
-    return new QFSFileEngine(fileName);
-#endif
+    return engine;
 }
 
 /*!