Add missing method findByData(QIODevice *)

3 files changed, 28 insertions, 1 deletions

diff --git a/src/mimetypes/qmimedatabase.cpp b/src/mimetypes/qmimedatabase.cpp
index 7925807..2d2ddcc 100644
--- a/src/mimetypes/qmimedatabase.cpp
+++ b/src/mimetypes/qmimedatabase.cpp
@@ -489,6 +489,29 @@ QMimeType QMimeDatabase::findByData(const QByteArray &data) const
 // ------------------------------------------------------------------------------------------------
 
 /*!
+    Returns a MIME type for the data in \a device.
+
+    A valid MIME type is always returned. If \a data doesn't match any
+    known MIME type data, the default MIME type (application/octet-stream)
+    is returned.
+*/
+QMimeType QMimeDatabase::findByData(QIODevice* device) const
+{
+    QMutexLocker locker(&d->mutex);
+
+    int accuracy = 0;
+    if (device->isOpen() || device->open(QIODevice::ReadOnly)) {
+        // Read 16K in one go (QIODEVICE_BUFFERSIZE in qiodevice_p.h).
+        // This is much faster than seeking back and forth into QIODevice.
+        const QByteArray data = device->read(16384);
+        return d->findByData(data, &accuracy);
+    }
+    return mimeTypeForName(d->defaultMimeType());
+}
+
+// ------------------------------------------------------------------------------------------------
+
+/*!
     Returns a MIME type for \a url.
 
     If the url is a local file, this calls findByFile.
diff --git a/src/mimetypes/qmimedatabase.h b/src/mimetypes/qmimedatabase.h
index 9c0465a..f8e1cd8 100644
--- a/src/mimetypes/qmimedatabase.h
+++ b/src/mimetypes/qmimedatabase.h
@@ -47,6 +47,7 @@ public:
     QMimeType mimeTypeForName(const QString &nameOrAlias) const;
     QMimeType findByName(const QString &fileName) const;
     QMimeType findByData(const QByteArray &data) const;
+    QMimeType findByData(QIODevice *device) const;
 
     QMimeType findByFile(const QString &fileName) const;
     QMimeType findByFile(const QFileInfo &fileInfo) const;
@@ -71,5 +72,5 @@ private:
 };
 
 QT_END_NAMESPACE
-  
+
 #endif   // QMIMEDATABASE_H_INCLUDED
diff --git a/tests/auto/qmimedatabase/tst_qmimedatabase.cpp b/tests/auto/qmimedatabase/tst_qmimedatabase.cpp
index 1ef2e54..9c24f27 100644
--- a/tests/auto/qmimedatabase/tst_qmimedatabase.cpp
+++ b/tests/auto/qmimedatabase/tst_qmimedatabase.cpp
@@ -229,6 +229,9 @@ void tst_qmimedatabase::test_findByFileWithContent()
     tempFile.close();
     mime = db.findByFile(tempFileName);
     QCOMPARE(mime.name(), QString::fromLatin1("application/pdf"));
+    QFile file(tempFileName);
+    mime = db.findByData(&file); // QIODevice ctor
+    QCOMPARE(mime.name(), QString::fromLatin1("application/pdf"));
     // by name only, we cannot find the mimetype
     mime = db.findByName(tempFileName);
     QVERIFY(mime.isValid());