QCryptographicHash: Add a static method to retrieve hash length

It's useful when you need to check how long a hash will be without first
generating one.

[ChangeLog][QtCore][QCryptographicHash] Add a static method, hashLength,
which returns the length of the output of a hash function in bytes.

Change-Id: Id6a454016523de83d157fd95c50105c6db4bb1d9
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>

1 files changed, 1 insertions, 0 deletions

diff --git a/src/corelib/tools/qcryptographichash.h b/src/corelib/tools/qcryptographichash.h
index 2f74d42405..ad1de7c756 100644
--- a/src/corelib/tools/qcryptographichash.h
+++ b/src/corelib/tools/qcryptographichash.h
@@ -101,6 +101,7 @@ public:
     QByteArray result() const;
 
     static QByteArray hash(const QByteArray &data, Algorithm method);
+    static int hashLength(Algorithm method);
 private:
     Q_DISABLE_COPY(QCryptographicHash)
     QCryptographicHashPrivate *d;