audio: common rate control code for timer based outputs

This commit removes the ad-hoc rate-limiting code from noaudio and
wavaudio, and replaces them with a (slightly modified) code from
spiceaudio.  This way multiple write calls (for example when the
circular buffer wraps around) do not cause problems.

Signed-off-by: Kővágó, Zoltán <DirtY.iCE.hu@gmail.com>
Message-id: fd0fe5b95b13fa26d09ae77a72f99d0ea411de14.1568927990.git.DirtY.iCE.hu@gmail.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

1 files changed, 10 insertions, 11 deletions

diff --git a/audio/wavaudio.c b/audio/wavaudio.c
index 78af2f1338..85f5ff9c28 100644
--- a/audio/wavaudio.c
+++ b/audio/wavaudio.c
@@ -35,21 +35,15 @@
 typedef struct WAVVoiceOut {
     HWVoiceOut hw;
     FILE *f;
-    int64_t old_ticks;
+    RateCtl rate;
     int total_samples;
 } WAVVoiceOut;
 
 static size_t wav_write_out(HWVoiceOut *hw, void *buf, size_t len)
 {
     WAVVoiceOut *wav = (WAVVoiceOut *) hw;
-    int64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
-    int64_t ticks = now - wav->old_ticks;
-    int64_t bytes =
-        muldiv64(ticks, hw->info.bytes_per_second, NANOSECONDS_PER_SECOND);
-
-    bytes = MIN(bytes, len);
-    bytes = bytes >> hw->info.shift << hw->info.shift;
-    wav->old_ticks = now;
+    int64_t bytes = audio_rate_get_bytes(&hw->info, &wav->rate, len);
+    assert(bytes >> hw->info.shift << hw->info.shift == bytes);
 
     if (bytes && fwrite(buf, bytes, 1, wav->f) != 1) {
         dolog("wav_write_out: fwrite of %" PRId64 " bytes failed\nReason: %s\n",
@@ -130,6 +124,8 @@ static int wav_init_out(HWVoiceOut *hw, struct audsettings *as,
                strerror(errno));
         return -1;
     }
+
+    audio_rate_start(&wav->rate);
     return 0;
 }
 
@@ -179,8 +175,11 @@ static void wav_fini_out (HWVoiceOut *hw)
 
 static int wav_ctl_out (HWVoiceOut *hw, int cmd, ...)
 {
-    (void) hw;
-    (void) cmd;
+    WAVVoiceOut *wav = (WAVVoiceOut *) hw;
+
+    if (cmd == VOICE_ENABLE) {
+        audio_rate_start(&wav->rate);
+    }
     return 0;
 }