@@ -156,34 +156,43 @@ static size_t qpa_read(HWVoiceIn *hw, void *data, size_t length)
{
PAVoiceIn *p = (PAVoiceIn *) hw;
PAConnection *c = p->g->conn;
- size_t l;
- int r;
+ size_t total = 0;
pa_threaded_mainloop_lock(c->mainloop);
CHECK_DEAD_GOTO(c, p->stream, unlock_and_fail,
"pa_threaded_mainloop_lock failed\n");
- if (!p->read_length) {
- r = pa_stream_peek(p->stream, &p->read_data, &p->read_length);
- CHECK_SUCCESS_GOTO(c, r == 0, unlock_and_fail,
- "pa_stream_peek failed\n");
- }
+ while (total < length) {
+ size_t l;
+ int r;
+
+ if (!p->read_length) {
+ r = pa_stream_peek(p->stream, &p->read_data, &p->read_length);
+ CHECK_SUCCESS_GOTO(c, r == 0, unlock_and_fail,
+ "pa_stream_peek failed\n");
+ if (!p->read_length) {
+ /* buffer is empty */
+ break;
+ }
+ }
- l = MIN(p->read_length, length);
- memcpy(data, p->read_data, l);
+ l = MIN(p->read_length, length - total);
+ memcpy((char *)data + total, p->read_data, l);
- p->read_data += l;
- p->read_length -= l;
+ p->read_data += l;
+ p->read_length -= l;
+ total += l;
- if (!p->read_length) {
- r = pa_stream_drop(p->stream);
- CHECK_SUCCESS_GOTO(c, r == 0, unlock_and_fail,
- "pa_stream_drop failed\n");
+ if (!p->read_length) {
+ r = pa_stream_drop(p->stream);
+ CHECK_SUCCESS_GOTO(c, r == 0, unlock_and_fail,
+ "pa_stream_drop failed\n");
+ }
}
pa_threaded_mainloop_unlock(c->mainloop);
- return l;
+ return total;
unlock_and_fail:
pa_threaded_mainloop_unlock(c->mainloop);
There is no guarantee a single call to pa_stream_peek every timer_period microseconds can read a recording stream faster than the data gets produced at the source. Let qpa_read try to drain the recording stream. To reproduce the problem: Start qemu with -audiodev pa,id=audio0,in.mixing-engine=off On the host connect the qemu recording stream to the monitor of a hardware output device. While the problem can also be seen with a hardware input device, it's obvious with the monitor of a hardware output device. In the guest start audio recording with audacity and notice the slow recording data rate. Signed-off-by: Volker Rümelin <vr_qemu@t-online.de> --- audio/paaudio.c | 41 +++++++++++++++++++++++++---------------- 1 file changed, 25 insertions(+), 16 deletions(-)