diff options
author | Volker RĂ¼melin <vr_qemu@t-online.de> | 2020-01-04 10:11:21 +0100 |
---|---|---|
committer | Gerd Hoffmann <kraxel@redhat.com> | 2020-01-06 08:47:16 +0100 |
commit | acc3b63e1bdf806de1a520522dd43e494461d3bb (patch) | |
tree | 46b225a36811a8aaaa52a7d602b342168fd50341 | |
parent | 4db3e634c77a671fadbba6d4d39e0d21232e5609 (diff) |
paaudio: try to drain the recording stream
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 RĂ¼melin <vr_qemu@t-online.de>
Message-id: 20200104091122.13971-4-vr_qemu@t-online.de
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
-rw-r--r-- | audio/paaudio.c | 41 |
1 files changed, 25 insertions, 16 deletions
diff --git a/audio/paaudio.c b/audio/paaudio.c index 7db1dc15f0..b23274550e 100644 --- a/audio/paaudio.c +++ b/audio/paaudio.c @@ -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); |