pulse - only underrun if no more data has been written

Original patch from David Henningsson <david.henningsson@canonical.com>

If more data has already been written after the underrun, the underrun
will automatically end and therefore we should not report it or
restart the stream.

[ This patch adds a more check of underrun with a new PA function so
  that the underrun handles works more reliably.  As the feature is
  supported only in a recent version of PA, the underrun handling is
  enabled as default now for the new PA, while it's still disabled for
  older PA.  -- tiwai ]

Signed-off-by: David Henningsson <david.henningsson@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/pulse/pcm_pulse.c b/pulse/pcm_pulse.c
index d6c6792f6d748c4101886d516963933bb8c70b4f..b0e52ab24ce3f8747906b15a4735f89053208f61 100644 (file)
--- a/pulse/pcm_pulse.c
+++ b/pulse/pcm_pulse.c
@@ -42,6 +42,7 @@ typedef struct snd_pcm_pulse {
        int handle_underrun;
 
        size_t offset;
+       int64_t written;
 
        pa_stream *stream;
 
@@ -460,6 +461,7 @@ static snd_pcm_sframes_t pulse_write(snd_pcm_ioplug_t * io,
 
        /* Make sure the buffer pointer is in sync */
        pcm->last_size -= writebytes;
+       pcm->written += writebytes;
        ret = update_ptr(pcm);
        if (ret < 0)
                goto finish;
@@ -585,6 +587,15 @@ static void stream_request_cb(pa_stream * p, size_t length, void *userdata)
        update_active(pcm);
 }
 
+#if defined(PA_CHECK_VERSION) && PA_CHECK_VERSION(0,99,0)
+#define DEFAULT_HANDLE_UNDERRUN                1
+#define do_underrun_detect(pcm, p) \
+       ((pcm)->written <= pa_stream_get_underflow_index(p))
+#else
+#define DEFAULT_HANDLE_UNDERRUN                0
+#define do_underrun_detect(pcm, p)     1       /* always true */
+#endif
+
 static void stream_underrun_cb(pa_stream * p, void *userdata)
 {
        snd_pcm_pulse_t *pcm = userdata;
@@ -594,7 +605,8 @@ static void stream_underrun_cb(pa_stream * p, void *userdata)
        if (!pcm->p)
                return;
 
-       pcm->underrun = 1;
+       if (do_underrun_detect(pcm, p))
+               pcm->underrun = 1;
 }
 
 static void stream_latency_cb(pa_stream *p, void *userdata) {
@@ -739,6 +751,7 @@ static int pulse_prepare(snd_pcm_ioplug_t * io)
 
        pcm->offset = 0;
        pcm->underrun = 0;
+       pcm->written = 0;
 
        /* Reset fake ringbuffer */
        pcm->last_size = 0;
@@ -983,7 +996,7 @@ SND_PCM_PLUGIN_DEFINE_FUNC(pulse)
        const char *server = NULL;
        const char *device = NULL;
        const char *fallback_name = NULL;
-       int handle_underrun = 0;
+       int handle_underrun = DEFAULT_HANDLE_UNDERRUN;
        int err;
        snd_pcm_pulse_t *pcm;