From de803468291ae96f7c3900247364aa295fe1d9a1 Mon Sep 17 00:00:00 2001
From: Ivan Solovev <ivan.solovev@qt.io>
Date: Fri, 10 Sep 2021 11:46:33 +0200
Subject: [PATCH] QByteDataBuffer::getChar() - assert that buffer is not empty
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Found by CodeChecker.
The getChar() method can return a garbage value if called on an empty
buffer. Considering that QByteDataBuffer is an internal class and that
there seems to be no current usage of this method, just add a Q_ASSERT
to make sure that the buffer is not empty.

Task-number: QTBUG-96303
Pick-to: 6.2
Change-Id: Iab0aee596aabafe999996f83177ca8bba16a58b6
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>
Reviewed-by: Ievgenii Meshcheriakov <ievgenii.meshcheriakov@qt.io>
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
---
 src/corelib/text/qbytedata_p.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/corelib/text/qbytedata_p.h b/src/corelib/text/qbytedata_p.h
index 77f351cbb4..3c36085021 100644
--- a/src/corelib/text/qbytedata_p.h
+++ b/src/corelib/text/qbytedata_p.h
@@ -244,6 +244,8 @@ public:
 
     inline char getChar()
     {
+        Q_ASSERT_X(!isEmpty(), "QByteDataBuffer::getChar",
+                   "Cannot read a char from an empty buffer!");
         char c;
         read(&c, 1);
         return c;