Fix audio glitches in the audiooutput example.

The data copy loop didn't advance the write position, resulting in some
of the output buffer being overwritten and some of it not written to at
all.

Task-number: QTBUG-13751
Reviewed-by: Justin McPherson
(cherry picked from commit a006881b2297e4dbf03051f82a8abb1363ceeebb)

1 files changed, 2 insertions, 2 deletions

diff --git a/examples/multimedia/audiooutput/audiooutput.cpp b/examples/multimedia/audiooutput/audiooutput.cpp
index 2245748..6b64940 100644
--- a/examples/multimedia/audiooutput/audiooutput.cpp
+++ b/examples/multimedia/audiooutput/audiooutput.cpp
@@ -133,9 +133,9 @@ void Generator::generateData(const QAudioFormat &format, qint64 durationUs, int
 qint64 Generator::readData(char *data, qint64 len)
 {
     qint64 total = 0;
-    while (len - total) {
+    while (len - total > 0) {
         const qint64 chunk = qMin((m_buffer.size() - m_pos), len - total);
-        memcpy(data, m_buffer.constData() + m_pos, chunk);
+        memcpy(data + total, m_buffer.constData() + m_pos, chunk);
         m_pos = (m_pos + chunk) % m_buffer.size();
         total += chunk;
     }